Dissertations / Theses: 'Incremental sheet forming tool'

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Jackson, Kathryn Pamela. "The mechanics of incremental sheet forming." Thesis, University of Cambridge, 2008. https://www.repository.cam.ac.uk/handle/1810/267843.

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Incremental sheet forming (ISF) is a flexible process where an indenter moves over the surface of a sheet of metal to form a 3D shell incrementally by a progression of localised deformation. Despite extensive research into the process, the deformation mechanics is not fully understood. This thesis presents new insights into the mechanics of ISF applied to two groups of materials: sheet metals and sandwich panels. A new system for measuring tool forces in ISF is commissioned. The system uses six loadcells to measure reaction forces on the workpiece frame. Each force signal has an uncertainty of ±15 N. This is likely to be small in comparison to tool forces measured in ISF. The mechanics of ISF of sheet metals is researched. Through-thickness deformation and strains of copper plates are measured for single-point incremental forming (SPIF) and two-point incremental forming (TPIF). It is shown that the deformation mechanisms of SPIF and TPIF are shear parallel to the tool direction, with both shear and stretching perpendicular to the tool direction. Tool forces are measured and compared throughout the two processes. Tool forces follow similar trends to strains, suggesting that shear parallel to the tool direction is a result of friction between the tool and workpiece. The mechanics of ISF of sandwich panels is investigated. The mechanical viability of applying ISF to various sandwich panel designs is evaluated by observing failure modes and damage under two simple tool paths. ISF is applicable to metal/polymer/metal sandwich panels. This is because the cores and faceplates are ductile and largely incompressible, and therefore survive local indentation during ISF without collapse. Through-thickness deformation, tool forces and applicability of the sine law for prediction of wall thickness are measured and compared for a metal/polymer/metal sandwich panel and a monolithic sheet metal. The mechanical results for ISF of sheet metals transfer closely to sandwich panels. Hence, established knowledge and process implementation procedures derived for ISF of monolithic sheet metals may be used in the future for ISF of sandwich panels.

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Shankar, Ravi. "Surface reconstruction and tool path strategies for incremental sheet metal forming /." Aachen : Shaker, 2008. http://d-nb.info/989220230/04.

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Shankar, Ravi [Verfasser]. "Surface Reconstruction and Tool Path Strategies for Incremental Sheet Metal Forming / Ravi Shankar." Aachen : Shaker, 2008. http://d-nb.info/1162792094/34.

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Fritzen, Daniel. "Estudo do processo de estampagem incremental em chapa de latão 70/30." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/49294.

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O presente trabalho tem como objetivo avaliar o comportamento da chapa de latão 70/30 para o processo de Estampagem Incremental de Chapas (ISF - Incremental Sheet Forming), baseado nos parâmetros: ângulo de parede (ψ), passo vertical ( Z) e estratégia do caminho da ferramenta. Os experimentos baseiam-se na variante da Estampagem Incremental denominada Estampagem Incremental com Ponto Simples (SPIF - Single Point Incremental Forming). Foram realizados 18 ensaios usando uma ferramenta de estampar com raio (RT) de 5 mm. Para execução dos testes práticos, foram utilizados os recursos: softwares CAD/CAM, centro de usinagem CNC com três eixos, matriz incremental, ferramenta de estampagem incremental e um dispositivo prensa chapas. Além disso, o acabamento da superfície conformada foi medido através do parâmetro de rugosidade RZ nos principais ensaios, bem como a medição das deformações verdadeiras (j) e da espessura (s1). Os testes práticos demonstraram que a estratégia de usinagem espiral proporcionou um maior ângulo de parede, comparado à estratégia paralela de contorno.
This study aims to evaluate the behavior of 70/30 brass plate to the process of Incremental Sheet Forming - ISF, based on the parameters: wall angle (ψ), vertical step ( Z) and tool path strategy. The experiments were based on a variation of the ISF process, called SPIF (Single Point Incremental Forming). Eighteen tests were conducted using a punching tool with a radius (RT) of 5 mm. For the execution of practical tests, the resources were used: CAD / CAM software, CNC machining center with three axis. It was also used an incremental matrix, a tool for incremental forming and a sheet-press device. In addition, the surface finish was measured by RZ roughness parameter in the main tests, the same way the measurement of true strains (φ) and thickness (s1). The practice tests showed that the spiral machining strategy has provided a greater wall angle, compared to the parallel strategy contour.

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Maximiliano, Gerson. "Estampagem incremental de múltiplos passes em chapa de latão C268." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/149218.

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O presente trabalho investiga o comportamento da chapa de latão C268, com 0,50 mm de espessura, quando exposto ao processo de Estampagem Incremental de Chapas de Metal (Incremental Sheet Metal Forming -ISMF). Especificamente para a pesquisa, foram utilizadas as modalidades de Estampagem Incremental com Ponto Simples (Single Point Incremental Forming- SPIF) e Estampagem Incremental de Múltiplos Passes (Multi Pass Single Point Incremental Forming- MSPIF). Os experimentos foram baseados em uma geometria de tronco de pirâmide de base quadrada com 100 mm de lado e 45 mm de profundidade. Para as estratégias de estampagem foi atribuído, a estampagem helicoidal. Como resultado principal, foi verificado o ângulo de parede máximo atingido por cada processo de estampagem incremental. Adicionalmente, ensaios de tração, análise de deformações e de rugosidade da chapa de latão foram realizados. Todos os seus resultados estão detalhados na investigação. Para os parâmetros adotados nestes experimentos, o ângulo de parede obtido por SPIF foi maior do que pelo estudo proposto por MSPIF.
The present study investigates the performance of the brass plate C-268 with 0.50 mm thickness, when exposed to Incremental Sheet Metal Forming (ISMF). Specifically for research, it was used the modalities Single Point Incremental Forming (SPIF) and Multi Pass Single Point Incremental Forming (MSPIF). The experiments were based on a truncated pyramid geometry with square base 100 mm side and 45 mm depth. For forming strategies has been assigned, the helical forming. As the main outcome, it was found the maximum wall angle achieved by each process of incremental printing. In addition, tensile tests, analysis of deformation and roughness of the brass sheet were performed. All results are detailed in the investigation. For the parameters used in these experiments, the wall angle obtained by SPIF is greater than the study proposed by MSPIF.

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Daleffe, Anderson. "Estudo do processo de estampagem incremental em chapa de alumínio puro." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/16205.

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O presente trabalho estuda o processo de estampagem incremental em chapas de alumínio puro, descrevendo as ferramentas e um suporte prensa chapas. Estuda e pesquisa bibliograficamente e experimentalmente o processo de estampagem incremental. O trabalho apresenta os procedimentos de caracterização utilizados para determinar os limites do processo, aplicáveis para chapas de 0,5 mm de espessura em alumínio puro. A caracterização da chapa, juntamente com o ensaio mecânico de tração e os testes práticos de estampagem fornecerão um panorama da estampagem incremental, para algumas situações diversas sobre o tema. Para a execução dos testes práticos foi fabricado um dispositivo prensa chapas e um punção, matriz incremental e ferramenta de estampagem incremental, também foram feitas adaptações na máquina CNC, centro de usinagem CNC com três eixos.
This paper studies the process of incremental sheet forming, in plates the aluminum pure, describing the tools and support a press plates. Studies and literature search and experimentally the process of stamping incremental. The work presents the characterization of procedures used to determine the limits of the process, applicable to plates of 0.5 mm thick pure aluminum. The characterization of the plate, along with mechanical traction test and practical tests of printing provide an overview of incremental printing, for some different situations on the subject. For the practical implementation of the tests was a device manufactured press plates and a puncture, matrix and incremental tool for stamping incremental, were also made adjustments in the CNC machine, CNC machining center with three axles.

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Castelan, Jovani. "Estampagem incremental do titânio comercialmente puro àplicação em implante craniano." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/28829.

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Este trabalho apresenta um estudo sobre o uso do processo de estampagem incremental empregando chapas de titânio comercialmente puro. O modelo do componente empregado como foco do trabalho foi um implante craniano a base de titânio. Este tipo de implante é usado, por exemplo, em casos de acidentes em que a camada óssea do crânio foi perdida. Com auxílio de um sistema computacional CAD (Computer Aided Design), foi desenvolvido um modelo 3D, a partir de imagens de tomografia computadorizada. Foram determinadas as características mecânicas e biomédicas das chapas de titânio F67 - grau 2 e, através de software CAM, foi possível gerar as trajetórias de ferramenta, utilizadas na usinagem do molde e na estampagem da chapa. Os testes práticos demostraram que a estampagem incremental proporcionou maiores deformações do que a estampagem convencional e qual a estratégia de usinagem que proporcionou a maior homogeneidade na distribuição de espessura e conformidade dimensional das chapas estampadas.
This work present a research about the incremental sheet forming process, using commercially pure titanium sheets. The model of component used like focus on work was a titanium cranial implant. This kind of implant is used, e.g., in cases of accidents where skull bone was lost. With aided of a CAD computacional system (Computer Aided Design), was development a 3D model, with images of computadorized tomography. It was determined the mechanical and biomedical properties of the F67 grade 2 titanium sheet and, through CAM software, it was possible development the tool path, used in the milling mold and sheet forming. The pratical tests showed the incremental forming provided greater than convencional forming and which the tool movement strategy that provided better homogeneity in the thickness distribution and dimensional conformity of the forming sheets.

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Ali, Ahmed. "Incremental sheet metal forming." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0020/MQ54441.pdf.

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Powell, Nicholas Newton. "Incremental forming of flanged sheet metal components." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357609.

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Raithatha, Ankor Mahendra. "Incremental sheet forming : modelling and path optimisation." Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:89b0ac1e-cab4-4d80-b352-4f48566c7668.

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Incremental sheet forming (ISF) is a novel metal shaping technology that is economically viable for low-volume manufacturing, customisation and rapid-prototyping. It uses a small tool that is controlled by a computer-numerically controlled sequence and the path taken by this tool over the sheet defines the product geometry. Little is currently known about how to design the tool-path to minimise geometric errors in the formed part. The work here addresses this problem by developing a model based tool-path optimisation scheme for ISF. The key issue is how to generate an efficient model for ISF to use within a path optimisation routine, since current simulation methods are too slow. A proportion of this thesis is dedicated to evaluating the applicability of the rigid plastic assumption for this purpose. Three numerical models have been produced: one based on small strain deformation, one based on limit analysis theory and another that approximates the sheet to a network of rods. All three models are formulated and solved as second-order cone programs (SOCP) and the limit analysis based model is the first demonstration of an upper-bound shell finite element (FE) problem solved as an SOCP. The models are significantly faster than commercially available FE software and simulations are compared with experimental and numerical data, from which it is shown the rigid plastic assumption is suitable for modelling deformation in ISF. The numerical models are still too slow for the path optimisation scheme, so a novel linearised model based on the concept of spatial impulse responses is also formulated and used in an optimal control based tool-path optimisation scheme for producing axisymmetric products with ISF. Off-line and on-line versions of the scheme are implemented on an ISF machine and it is shown that geometric errors are significantly reduced when using the proposed method. This work provides a new structured framework for tool-path design in ISF and it is also a novel use of feedback to compensate for geometrical errors in ISF.

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Wang, Hao. "Incremental sheet forming process : control and modelling." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:a80370f5-2287-4c6b-b7a4-44f06211564f.

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Incremental Sheet Forming (ISF) is a progressive metal forming process, where the deformation occurs locally around the point of contact between a tool and the metal sheet. The final work-piece is formed cumulatively by the movements of the tool, which is usually attached to a CNC milling machine. The ISF process is dieless in nature and capable of producing different parts of geometries with a universal tool. The tooling cost of ISF can be as low as 5–10% compared to the conventional sheet metal forming processes. On the laboratory scale, the accuracy of the parts created by ISF is between ±1.5 mm and ±3mm. However, in order for ISF to be competitive with a stamping process, an accuracy of below ±1.0 mm and more realistically below ±0.2 mm would be needed. In this work, we first studied the ISF deformation process by a simplified phenomenal linear model and employed a predictive controller to obtain an optimised tool trajectory in the sense of minimising the geometrical deviations between the targeted shape and the shape made by the ISF process. The algorithm is implemented at a rig in Cambridge University and the experimental results demonstrate the ability of the model predictive controller (MPC) strategy. We can achieve the deviation errors around ±0.2 mm for a number of simple geometrical shapes with our controller. The limitations of the underlying linear model for a highly nonlinear problem lead us to study the ISF process by a physics based model. We use the elastoplastic constitutive relation to model the material law and the contact mechanics with Signorini’s type of boundary conditions to model the process, resulting in an infinite dimensional system described by a partial differential equation. We further developed the computational method to solve the proposed mathematical model by using an augmented Lagrangian method in function space and discretising by finite element method. The preliminary results demonstrate the possibility of using this model for optimal controller design.

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Siddiqi, Muftooh Ur Rehman. "An empirical feasibility assessment for incremental sheet forming." Thesis, University of Strathclyde, 2016. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27902.

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Many sheet forming processes such as hammering and spinning, have been used in the manufacturing industry for decades and consequently have strengths and weakness that are well known. In contrast, Incremental Sheet Forming (ISF) is an emerging type of forming process whose capabilities are not yet fully understood. So while it is clear that ISF processes have several advantages, such as low cost and good surface finish [sic]. It has proved difficult to define the limits of the process in terms of macro-parameters such as deformation and sheet thickness. So whereas the capabilities of many sheet metal manufacturing processes are effectively characterized by forming limit curves this has not been possible with ISF. In other words, there is a lack of methodologies for assessing the feasibility of using ISF for particular components. This thesis investigates several aspects of the ISF process and develops a quantitative methodology that allows a first approximation of the feasibility of component manufacturing using the ISF process in terms of deflection and thickness reduction. It was found that thickness reduction can be accurately modeled in terms of analytical model developed for sheet metal forming. The predictions of the method are assessed and found to give a good correspondence with measured data for the range of wall angles, materials and geometries assessed. The parameters of the proposed methodology have been determined by experimental studies of commercially pure Titanium Grade 4 (CpTi), Aluminium alloys (AA1050-H-14, AA2024-O and AA7075-O) and Stainless Steel (SS304-L) to understand the process of incremental sheet forming and its impact on the final properties of the sheet metal. The proposed method called “ISF-FCheck” uses two charts to quantify maximum strain in relation to the depth and thickness reduction. Discussion of these results has also supported the development of a more detailed understanding of the interaction of the process parameters and lead to a new theoretical and graphical representation of the ISF process.

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Shouler, Daniel Reginald. "Expanded forming limit testing for sheet forming processes." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609473.

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Bambach, Markus. "Process strategies and modelling approaches for asymmetric incremental sheet forming." Aachen Shaker, 2007. http://d-nb.info/988445239/04.

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Bambach, Markus. "Process strategies and modelling approaches for asymmetric incremental sheet forming /." Aachen : Shaker, 2008. http://d-nb.info/988445239/04.

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Bagudanch, Frigolé Isabel. "Incremental sheet forming applied to the manufacturing of biocompatible polymer prostheses." Doctoral thesis, Universitat de Girona, 2017. http://hdl.handle.net/10803/461838.

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Incremental Sheet Forming (ISF) technology has been mainly applied on metallic sheets during the last years. ISF is used due to its flexibility, low costs, low batch production, production of complex geometries and customized prodcuts. For this reason ISF seems to be the ideal process for prosthesis production. The main objective of the thesis is to study the ISF technology, considering Single Point Incremental Forming (SPIF) and Two Point Incremental Forming (TPIF) variants, on biocompatible polymers to obtain a real customized cranial implant. The methodology is based on the following steps: a) Experimental work in SPIF to produce basic geometries using non-biocompatible and biocompatible polymers, b) Study of the influence of the process parameters, c) Case study: customized cranial implant. Achieving the objectives established in these stages will permit to improve the knowledge about ISF process in order to successfully manufacture customized implants at a low cost and reduced time-to-market
La tecnologia de deformació incremental de xapa (ISF) s’ha aplicat majoritàriament en metalls durant els últims anys. Aquesta tecnologia es caracteritza per la flexibilitat del procés amb costos baixos, producció en lots petits, obtenció de geometries complexes i personalització del producte, el que fa que un dels camps d’aplicació de la tecnologia sigui la fabricació de pròtesis. L’objectiu principal és el d’estudiar la tecnologia ISF, en les seves variants de Single Point Incremental Forming (SPIF) i Two Point Incremental Forming (TPIF), sobre polímers biocompatibles per obtenir una pròtesi de crani personalitzada. La metodologia es basa en: a) Experimentació en SPIF de geometries bàsiques utilitzant polímers no biocompatibles i biocompatibles, b) Determinació de la influència dels paràmetres de procés, c) Cas d’estudi: pròtesi de crani personalitzada. L’assoliment d’aquestes etapes permetrà obtenir satisfactòriament pròtesis personalitzades de crani amb un baix cost i un temps de fabricació reduït

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Bambach, Markus [Verfasser]. "Process Strategies and Modelling Approaches for Asymmetric Incremental Sheet Forming / Markus Bambach." Aachen : Shaker, 2008. http://d-nb.info/1162791357/34.

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Gatea, Shakir Madhloom. "Experimental and numerical investigation of formability and ductile fracture in incremental sheet forming." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/47567/.

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Incremental sheet forming (ISF), also referred to as single point incremental forming (SPIF), is a relatively new, flexible forming process. The ISF process has excellent adaptability to CNC milling machines due to the fact that it does not require the use of high capacity presses or specific dies and is easy to automate for both symmetric and non-symmetric shapes. In SPIF, a blank sheet is fixed by a holder onto a CNC milling machine. A workpiece is formed by the action of a small hemispheric tool in contact with the blank moving along a user-specified tool path and incrementally deforming the blank into the desired shape. According to the technical characteristics of ISF, it can be used to manufacture small batch and customised products. SPIF is a promising technique, which could be further developed as an alternative manufacturing approach for customised medical parts, e.g. cranial plates, with considerable benefits in lead time and cost reduction. This thesis reports the findings of finite element (FE) analyses and experimental investigations into the formability and fracture in the ISF process, and their application with regard to manufacturing cranial plates, as well as the applicability of using the ISF process to form aluminium matrix composite (AMC). A modified Gurson–Tvergaard-Needleman (GTN) damage constitutive model was developed with the consideration of shear. The developed GTN model was implemented in Abaqus/Explicit via a VUMAT user subroutine to predict ductile fracture in the ISF process due to void nucleation, growth and coalescence. In comparison with experimental testing, there is a good agreement in the occurrence of fracture. The results also show that shear plays a role under meridional tensile stress in accelerating fracture propagation in ISF processes. The Nakajima test was used to construct the forming limit curve at necking (FLCN) and fracture (FLCF) for pure titanium sheet. The results of the FLCF are compared with those of the ISF to evaluate the ability of the Nakajima test to describe the fracture in ISF. Due to the fact that the GTN model can be used to capture fracture occurrence at high stress triaxiality, and the shear modified GTN model was developed to predict the fracture at zero stress or even negative stress triaxiality, the original GTN model and shear modified GTN model may not be suitable to predict the fracture in all samples of the Nakajima test, as some samples are deformed under moderate stress triaxiality. Therefore, another GTN based model with the consideration of stress triaxiality was developed to predict fracture in the Nakajima specimens under different stress triaxiality. The experimental and FE results showed that the shear modified GTN model predicted the fracture accurately with samples under uniaxial tension conditions due to low stress triaxiality and the original GTN model was suitable for an equi-biaxial strain state (high stress triaxiality). On the other hand, the stress triaxiality modified GTN model should be used for samples which have moderate stress triaxiality. The Nakajima test can be applied to establish the FLCF, which in turn can be utilized to describe the formability of the SPIF test for conical and pyramidal truncated specimens. Experiments and FE analyses were conducted to evaluate the influence of major forming parameters, including the step size, feed rate and tool size, on the formability and fracture of pure titanium. Two types of pure Ti (grades 1 and 2) were used to evaluate the sensitivity of the material type to forming parameters. It was found that the ISF parameters have different degrees of effect on the formability and fracture occurrence of pure titanium, and that grade 2 pure Ti is more sensitive to forming parameters. The optimal parameters from the parametric study were used to investigate the feasibility of using ISF to form a cranial plate; the results show that ISF can satisfactorily form a cranial plate. By evaluating the deformation and fracture mechanisms of a 6092Al alloy metal matrix composite reinforced with 17.5p vol. % SiC particles (6092Al/SiCp), the applicability of the ISF process to form the 6092Al/SiCp aluminium matrix composite (AMC) was investigated. Tensile tests were carried out at different strain rates to study the microstructure and topography of the 6092Al/SiCp sheet by scanning electron microscopy (SEM), coupled with energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results show that this AMC material at T6 condition is brittle due to the formation of precipitations as a result of either the interaction between the Al and SiCp or from hardening precipitation treatment e.g. Al2Cu, Al4Cu2Mg8Si7 and MgAl2. O-condition annealing was therefore used to reduce the detrimental effect of the intermetallic compounds in the interface region and can improve the fracture toughness and ductility of the material. However, the Al/SiC sheet treated with O-condition annealing is more sensitive to the strain rate than that treated with T6. By investigating the feasibility of using SPIF to form AMC sheets for the first time, the results show that the 6092Al/SiCp sheets can be satisfactorily formed after O-condition annealing.

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Imbert, Boyd Jose. "Increased Formability and the Effects of the Tool/Sheet Interaction in Electromagnetic Forming of Aluminum Alloy Sheet." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/857.

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This thesis presents the results of experimental and numerical work carried out to determine if electromagnetic forming (EMF) increases the formability of aluminum alloy sheet and, if so, to determine the mechanisms that play a role in the increased formability. To this end, free form (open cavity) and conical in-die samples were produced to isolate high strain rate constitutive and inertial effects from the effects of the interaction between the die and the sheet. Aluminum alloys AA5754 and AA6111 in the form of 1mm sheet were chosen since they are currently used in automotive production and are candidates for lightweight body panels. The experiments showed significant increases in formability in the conical die samples in areas where significant contact with the tool occurred, with no significant increase recorded for the free-formed samples. This indicates that the tool/sheet interaction is playing the dominant role in the increase in formability observed. Metallographic and fractographic analysis performed on the samples showed evidence of microvoid damage suppression, which may be a contributing factor to the increase in formability. Numerical modeling was undertaken to analyse the details of the forming operation and to determine the mechanisms behind the increased formability. The numerical calculations were performed with an explicit dynamic finite element structural code, using an analytical electromagnetic pressure distribution. Microvoid damage evolution was predicted using a microvoid damage subroutine based on the Gurson-Tvergaard-Needleman constitutive model. From the models it has been determined that the free forming process is essentially a plane-stress process. In contrast, the tool/sheet interaction produced in cone forming makes the process unique. When the sheet makes contact with the tool, it is subject to forces generated due to the impact, and very rapid bending and straightening. These combine to produce complex non-linear stress and strain histories, which render the process non-plane stress and thus make it significantly different from conventional sheet forming processes. Another characteristic of the process is that the majority of the plastic deformation occurs at impact, leading to strain rates on the order of 10,000 s^-1. It is concluded that the rapid impact, bending and straightening that results from the tool/sheet interaction is the main cause of the increased formability observed in EM forming.

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Sena, José Ilídio Velosa de. "Advanced numerical framework to simulate incremental forming processes." Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14809.

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Doutoramento em Engenharia Mecânica
The framework of the present work supports the numerical analysis of the Single Point Incremental Forming (SPIF) process resorting to a numerical tool based on adaptive remeshing procedure based on the FEM. Mainly, this analysis concerns the computation time reduction from the implicit scheme and the adaptation of a solid-shell finite element type chosen, in particular the Reduced Enhanced Solid Shell (RESS). The main focus of its choice was given to the element formulation due to its distinct feature based on arbitrary number of integration points through the thickness direction. As well as the use of only one Enhanced Assumed Strain (EAS) mode. Additionally, the advantages include the use of full constitutive laws and automatic consideration of doublesided contact, once it contains eighth physical nodes. Initially, a comprehensive literature review of the Incremental Sheet Forming (ISF) processes was performed. This review is focused on original contributions regarding recent developments, explanations for the increased formability and on the state of the art in finite elements simulations of SPIF. Following, a description of the numerical formulation behind the numerical tools used throughout this research is presented, summarizing non-linear mechanics topics related with finite element in-house code named LAGAMINE, the elements formulation and constitutive laws. The main purpose of the present work is given to the application of an adaptive remeshing method combined with a solid-shell finite element type in order to improve the computational efficiency using the implicit scheme. The adaptive remeshing strategy is based on the dynamic refinement of the mesh locally in the tool vicinity and following its motion. This request is needed due to the necessity of very refined meshes to simulate accurately the SPIF simulations. An initially mesh refinement solution requires huge computation time and coarse mesh leads to an inconsistent results due to contact issues. Doing so, the adaptive remeshing avoids the initially refinement and subsequently the CPU time can be reduced. The numerical tests carried out are based on benchmark proposals and experiments purposely performed in University of Aveiro, Department of Mechanical engineering, resorting to an innovative prototype SPIF machine. As well, all simulations performed were validated resorting to experimental measurements in order to assess the level of accuracy between the numerical prediction and the experimental measurements. In general, the accuracy and computational efficiency of the results are achieved.
O presente trabalho assenta na análise numérica do processo de Estampagem Incremental por Único Ponto (SPIF) recorrendo ao refinamento adaptativo da malha através do Método dos Elementos Finitos (FEM). Nomeadamente, a atenção é dada à redução do tempo de cálculo baseado no esquema de integração implícito em combinação com um elemento finito do tipo “sólidocasca” predefinido. O principal motivo da escolha do tipo de elemento finito deve-se à sua formulação possibilitar a atribuição de um número arbitrário de pontos de integração na direção da espessura combinado com a utilização de um único modo de deformação acrescentada e integração reduzida no plano. Além disso, as vantagens incluem a utilização de leis constitutivas tridimensionais, análise automática de contacto em dupla face e espessura, uma vez que é um elemento hexaédrico de 8 nós. Inicialmente, uma revisão da literatura relacionada com o processo de estampagem incremental (ISF) é apresentada evidenciando as contribuições recentemente desenvolvidas, explicações do aumento da formabilidade do material em ISF e com maior ênfase o estado-de-arte das simulações numéricas pelo FEM do processo SPIF. Seguidamente, é apresentado a descrição dos conceitos teóricos que suportam e foram utilizados ao longo desta pesquisa, resumindo tópicos de mecânica não-linear relacionada com o código LAGAMINE, formulação de elementos finitos e leis constitutivas. O principal objetivo do presente trabalho é a aplicação do método de refinamento adaptativo combinado com um elemento finito sólido-casca, a fim de melhorar a eficiência computacional usando o esquema de integração implícito. A estratégia de refinamento adaptativo é baseada no refinamento dinâmico da malha localmente na proximidade da ferramenta e acompanhando o seu movimento. Este requisito é devido à necessidade de malhas muito refinadas para simular com precisão as simulações SPIF. A malha inicialmente refinada requer enorme tempo de cálculo e uma malha grosseira leva a resultados inconsistentes devido a problemas de contato. Neste sentido, o refinamento adaptativo evita o refinamento inicial total da malha e consequentemente melhora a performance computacional da simulação. Os testes numéricos realizados são baseados em casos estudo e em testes experimentais realizados na Universidade de Aveiro, Departamento de Engenharia Mecânica, recorrendo a uma máquina protótipo inovadora construída propositadamente para SPIF. Todas as simulações realizadas são validadas recorrendo às medições experimentais, de modo a avaliar o nível de precisão entre a previsão numérica e as medições experimentais. Em geral, a precisão e a eficiência computacional dos resultados são alcançados.

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Afonso, Daniel Gil. "Industrial applicability of single point incremental forming : functional and energetic approach." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/21534.

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Doutoramento em Engenharia Mecânica
Incremental sheet forming processes like single point incremental forming have been majorly studied since the beginning of the 2000's. Besides the applications in the prototyping eld, ISF processes can also be used to the manufacture of unique parts and small batches. This possibility has a great potential for speed up new product development and to make products in smaller series economically viable. Also, this capability leads to a new business possibilities, enable the development of exclusive or custom products. However, mainly due to its novelty, SPIF industrial operation is still very apprehensive with just a few examples of application. The main purpose of the present work is to create tools that can be used for the SPIF process management and present examples of usage in di erent industrial elds. The SPIF process is studied using the SPIF-A machine design and built at the Department of Mechanical Engineering at the University of Aveiro. Despite being a free form manufacture process, SPIF has some geometric limitations, manly due to the forming mechanics and formability limit of the materials. The possible part con gurations and the design orientation are settled, allowing a suitable part development. The hardware to perform incremental forming operations is outlined and the forming process is described, presenting alternative solutions both based on experimental work and state of the art review. A group of parts are developed and manufactured using SPIF as examples of industrial application. Parts are developed and evaluated to meet design and development requirements. New applications using SPIF as a rapid tooling process, typically exclusive form additive manufacturing technologies, are developed. The parity between SPIF and AM processes encounter industrial applications not only in prototyping or part manufacturing but also in tool development and fabrication. This novelty allows to decrease the time to market, decrease tooling cost and increase tooling complexity and consequential part design freedom in sheet metal moulds. The concept is developed and proof for a variety of thermoplastic and composite materials processing technologies.
Os processos de estampagem incremental de chapa, como a estampagem incremental por ponto unico, t^em sido estudados em profundidade desde o in cio dos anos 2000. Para al em da aplica c~ao no desenvolvimento de prot otipos, os processo de estampagem incremental apresentam potencial de aplica c~ao no fabrico de produto unicos ou pequenos lotes. Esta possibilidade oferece vantagens ao permitir acelerar o processo de design e desenvolvimento de produto e ao tornar economicamente vi avel a produ c~ao de pequenas s eries. Para al em disso, esta possibilidade permite a cria c~ao de novas tipologias de neg ocio, possibilitando o desenvolvimento e fabrico de produtos exclusivos ou customizados. No entanto, principalmente devido a novidade do processo, a estampagem incremental ainda n~ao tem muitos exemplos de aplica c~ao em empresas. O principal objetivo do trabalho apresentado e desenvolver ferramentas que possam ser utilizadas para a industrializa c~ao do processo de estampagem incremental por ponto unico e apresentar exemplos de aplica c~oes em diferentes areas industriais. A m aquina SPIF-A desenvolvida no Departamento de Engenharia Mec^anica da Universidade de Aveiro e utilizada para o estudo do processo de estampagem incremental. Apesar do potencial do processo de estampagem para fabricar superf cies de forma livre, existem algumas limita c~oes. Estas devem-se maioritariamente ao comportamento do material e ao processo e par^ametros de estampagem. S~ao de nidas linhas orientadoras para o design de pe cas, bem como as poss veis con gura c~oes, de forma a possibilitar o desenvolvimento de pe cas fact veis. O equipamento necess ario para a realiza c~ao de trabalhos de estampagem incremental e os par^ametros de trabalho s~ao estudados com recurso a an alise de estado da arte e a trabalho experimental. Como exemplo de aplica c~ao industrial da estampagem incremental, s~ao desenvolvidas e fabricadas pe cas. Os produtos s~ao desenvolvidos e avaliados de forma a garantir o cumprimento dos requisitos de nidos. S~ao propostas novas aplica c~oes para a utiliza c~ao de estampagem incremental para o fabrico r apido de ferramentas, tipicamente exclusivo do processos de fabrico aditivo. A analogia entre a estampagem incremental e o fabrico aditivo permite encontrar aplica c~oes industriais para al em da prototipagem, com grande potencial para o desenvolvimento e fabrico de ferramentas. Esta novidade contribui para a redu c~ao do tempo de comercializa c~ao, reduzindo custos e permitindo uma maior exibilidade do desenho de um produto. O conceito de fabrico de moldes em chapa para diversos materiais termopl asticos e comp ositos e desenvolvido e analisado.
Les processus de formage incr emental de t^ole, come formage incr emental un point, sont etudi es en profondeur d es le d ebut des ann ees 2000. Les processus ont son application dans le d eveloppement des prototypes et pr esentent aussi du vrai potentiel dans la fabrication des produits uniques et dans des petits lots. Cette possibilit e o re des avantages parce que permit d'acc el erer le processus de design et d eveloppement de produit et de faire le projet des petites s eries economiquement viables. En plus, formage incr emental possibilit e la cr eation des nouvelles typologies de a aires a cause de ca contribution dans la fabrication des produits personnalis es et exclusives. Malgr e ca et comme celui est un processus tr es r ecent, pour l'instant, le formage incr emental n'a pas beaucoup de utilisation industrielle. L'objectif principal du travail pr esent e est de d evelopper des moyens que peut ^etre utilis es pour auxili e l'industrialisation do processus de formage incr emental un point et pr esenter des exemples pour des distinctes applications industrielles. La machine SPIF-A d evelopp e dans le D epartement de Ing enierie M ecanique de l'Universit e d'Aveiro est utilis ee pour l' etude du processus de formage incr emental. Nonobstant le potentiel du processus de formage incr emental pour fabriquer des surfaces de forme libre il y a quelques limitations g eom etriques. C a d epend du comportement du mat eriel et les param etres de travail. Les con gurations g eom etriques possibles et les lignes directrices de conception sont d e nies de fa con a possibilit e le dessein des pi eces faisables. L'Equipment n ecessaire pour la r ealisation des travaux de formage incr ementa et les param etres de travail sont etudi es en utilisant l'analyse de l' etat de l'art et des travaux exp erimentaux. Comme exemple des applications industrielles du formage incr emental, sont d evelopp ees et fabriqu es des pi eces. Les produits sont d evelopp es et avalis es de fa con a assurer qu'il respecte les exigences d e nis.

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Jadhav, Sanjay [Verfasser]. "Basic Investigations of the Incremental Sheet Metal Forming Process on a CNC Milling Machine / Sanjay Jadhav." Aachen : Shaker, 2005. http://d-nb.info/1181616417/34.

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Fritzen, Daniel. "Estudo dos parâmetros de conformabilidade para o processo de estampagem incremental." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/150566.

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Este trabalho apresenta um estudo sobre o processo de Estampagem Incremental de Chapas, em Latão C-268 de diferentes espessuras (s0: 0.50, 0.70 e 1.00 mm), motivado pela inobservância de pesquisas desta matéria prima neste processo de conformação de chapas. Atualmente, este material tem grande aplicação na confecção de utensílios domésticos (baixelas, travessas, etc) e ferragens para construção civil (espelhos, cubas, etc), instrumentos musicais de sopro e núcleos de radiadores automotivos, tendo assim, um amplo campo de aplicação industrial, e potencial para as aplicações do processo de Estampagem Incremental de Chapas. A pesquisa está pautada na caracterização das matérias primas, para a obtenção de dados como as Curvas de Escoamento, Índices de Anisotropia (r), Curvas Limite de Conformação (CLC) e em experimentos de Estampagem Incremental de Chapas, realizados em uma máquina dedicada a este processo de conformação. Para a realização dos experimentos, foram utilizados Incrementos Verticais com diferentes valores (∆Z: 0.10, 0.50 e 1.00 mm), assim como duas ferramentas de estampagem (DT: Ø10 e Ø15 mm). Foram aplicadas duas formas geométricas diferentes: Tronco de Cone e Tronco de Pirâmide, ambos com perfil radial das paredes verticais. Ao todo, foram realizados 15 experimentos diferentes na modalidade SPIF. Os experimentos foram realizados em uma máquina dedicada ao processo, capaz da aquisição dos valores de Força (FX, FY e FZ) durante a realização dos testes. Com a realização dos experimentos SPIF, foi possível a elaboração da Linha Limite de Fratura – LFC da chapa latão C-268 nas três espessuras investigadas, onde os resultados apontam para valores maiores de deformação verdadeira (1 vs 2), quando comparados aos valores da CLC. Adicionalmente, a LFC das três espessuras de chapas analisadas, apontam os valores das maiores deformações verdadeiras (1) muito próximos, evidenciando neste caso que a diminuição do Incremento Vertical (∆Z) é mais relevante para a estampagem do que o aumento da espessura da chapa. As geometrias Tronco de Cone e Tronco de Pirâmide apresentaram discrepâncias geométricas toleráveis em relação ao perfil projetado, mas diferentes entre si, influenciados pelo retorno elástico diferente de cada geometria. Entretanto, suas fraturas apresentaram o mesmo comportamento, propagação no sentido meridional. Os experimentos SPIF realizados com a ferramenta de estampagem com Ø10mm proporcionaram as maiores profundidades. A medição da espessura final (s1) próximas as regiões fraturadas, comprovou os valores medidos não ultrapassaram os respectivos valores resultantes da expressão matemática Lei do Seno, e ainda, que quanto menor a espessura inicial (s0) da chapa, menor a variação dos valores medidos e calculados. A análise das Forças (FX, FY e FZ) resultantes do processo SPIF mostram que quanto maior o Incremento Vertical (∆Z), maior a espessura inicial (s0) da chapa, e maior do diâmetro (DT) da ferramenta de estampagem, maiores serão as Forças necessárias no SPIF. Adicionalmente, foi possível determinar os valores de Atrito (µ), obtidos em função das Forças (FX, FY e FZ) do processo SPIF.
This paper presents a study of the Incremental Sheet Forming process, in Brass C-268 of different thicknesses (s0: 0.50, 0.70 and 1.00 mm), motivated by non-observance of research of this raw material in this sheet forming process. Currently, this material has great application in the manufacture of household items (plates, platters, etc.) and hardware for building (locks, vats, etc.), wind musical instruments and automotive radiator cores, having thus, a large industrial application field, and potential for the applications of the Incremental Sheet Forming process. The research is based on the characterization of raw materials, to obtain data such as Flow Curves, Anisotropy Indices (r), Forming Limit Curve and in Incremental Sheet Forming experiments, performed on a machine dedicated to this forming process. For the realization of the experiments, Vertical Increments with different values were used (∆Z: 0.10, 0.50 e 1.00 mm), As well as two forming tools (DT: Ø10 e Ø15 mm). Two different geometric forms were applied: Cone Frustum and Pyramid Frustum, both with radial profile of vertical walls. In all, 15 different SPIF experiments were performed. The experiments were carried out in a machine dedicated to the process, able to acquire the values of Force (FX, FY e FZ) during the tests. With the realization of SPIF experiments, it was possible to elaborate the Fracture Forming Line – FFL of Brass C-268 sheet, In the three thicknesses investigated, Where the results indicate higher values of true strain (1 vs 2), when compared to the FLC values. Additionally, the FFL of the three sheet thicknesses analyzed, indicate the values of the highest true deformations (1) very close, evidencing in this case, that the decrease of Vertical Increment (∆Z) is more relevant for the forming than the increase in sheet thickness. The Cone Frustum and Pyramid Frustum geometries presented tolerable geometric discrepancies in relation to the projected profile, more different from each other, influenced by different springback of each geometry. However, their fractures presented the same behavior, meridional direction propagation. The SPIF experiments performed with the forming tool with Ø10mm provided the greatest depths. The final thickness (s1) measurement near the fractured regions, proved the measured values did not exceed the respective values resulting from the mathematical expression Sine Law, and also, that the lower the initial thickness (s0) of sheet, lower the variation of the measured and calculated values. Analysis of Forces (FX, FY e FZ) resulting from the SPIF process, show that the larger the Vertical Increment (∆Z), larger the initial thickness (s0) of the sheet, and larger diameter (DT) of the forming tool, larger will be the necessary forces in SPIF. In addition, it was possible to determine the values of Friction (µ), obtained in function of the SPIF Forces (FX, FY e FZ).

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W, Lindvall Fredrik. "On tool steel, surface preparation, contact geometry and wear in sheet metal forming." Licentiate thesis, Karlstads universitet, Avdelningen för maskin- och materialteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-8883.

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In sheet metal forming operations the life length of the production equipment islargely dependent on the wear of the tools that are in direct contact with the sheet.One form of adhesive wear where some sheet material gets transferred to the tool, alsoknown as galling, is the most common cause of tool failure. The transferred materialsticks firmly to the tool and will scratch subsequent sheets and increase friction, renderingthem anywhere from aesthetically unsightly to completely ripped apart. Withcareful combination of several parameters the tools production life can be significantlyextended. The surface preparation of the tools has a large influence on the tool life, thesurface has to be smooth and yet not without texture. It was shown in strip reductiontesting that the orientation as well as the depth of the surface texture left by polishinginfluenced the tool life and that a texture perpendicular to the sliding direction was toprefer. The geometry of the forming tool is also a parameter to take into account as itinfluences the tool life not only by changing the contact pressure but also in itself. Ina sliding against flat sheet test rig a lower contact pressure increased the sliding distanceto galling. When two different geometries were compared at the same contactpressure it was found that there was a difference in tool life. As to the tool itself thematerial it’s made of influences the wear rate and tool life. Different tool steels wasinvestigated in sliding wear against metal sheets; Vancron 40 performed better thanVanadis 6 and S290PM performed better than a AISI M2 grade steel.

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Castelan, Jovani. "Utilização das tecnologias CAD/CAM para estampagem incremental do alumínio série 1000." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/12582.

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Este trabalho descreve a adaptação de um equipamento CNC e ferramentas computacionais CAD/CAM (desenvolvidas originalmente para a área de usinagem) na conformação de chapas de alumínio comercialmente puro, através do processo de estampagem incremental. Através das simulações e dos testes reais foi possível obter resultados práticos, relativos às limitações geométricas e ao acabamento superficial. As peças conformadas têm o formato básico de um tronco de cone, onde foram alterados a profundidade e o ângulo do cone. A análise dimensional das peças, comparadas com seu respectivo modelo CAD revelou razoável conformidade geométrica. Por outro lado, ângulos de parede maiores que 65° causaram o rompimento da chapa. As estampagens foram realizadas em um centro de usinagem, e utilizaram-se como valores máximos a velocidade de avanço de 2.200 mm/min e o incremento vertical de 1mm, por questões de segurança e também pela constatação de problemas de acabamento superficial e de vibrações excessivas do equipamento. Como conclusão final, foi demonstrado que, para o tipo específico de peça (material, espessura e geometria), dispositivo prensa-chapas, ferramentas, equipamento CNC e softwares utilizados, o processo de estampagem incremental seria viável para lotes de até 600 peças.
This paper describes the adaptation of a CNC equipment and CAD/CAM computational tools (originally developed for the machining area) on the conformation of sheets of commercially pure aluminum, through the process of incremental forming. Through simulations and tests were unable to get practical results, for the geometric constraints and surface finishing. Forming parts have the basic format of a truncated cone, which have changed the depth and angle of the cone. A dimensional analysis of the parts, compared with their CAD model showed geometric reasonable compliance. Moreover, the wall angles greater than 65 ° caused the breaking of the plate. The sheets formings were performed in a machining center, with a maximum speed of advance of 2,200 mm/min and the vertical increase of 1mm, for reasons of safety and also for finding finishing surface problems and the excessive vibration equipment. As final conclusion, it was demonstrated that, for the specific type of piece (material, thickness and geometry), device-press plates, tools, CNC equipment and software used, the process of incremental sheet forming feasible for batches of up to 600 pieces.

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Esmaeilpour, Mohammad Rasoul. "Finite Element Simulation of Single Point Incremental Sheet Forming with Barlat 2004Yield Function, CPFEM, and 3D RVE." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1543170842564928.

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Heikkilä, Irma. "The Positive Effect of Nitrogen Alloying of Tool Steels Used in Sheet Metal Forming." Doctoral thesis, Uppsala universitet, Tillämpad materialvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-198747.

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Sheet metal forming processes are mechanical processes, designed to make products from metal sheet without material removal. These processes are applied extensively by the manufacturing industry to produce commodities such as heat exchangers or panels for automotive applications. They are suitable for production in large volumes. A typical problem in forming operations is accumulation of local sheet material adherents onto the tool surface, which may deteriorate the subsequent products. This tool failure mechanism is named galling. The aim of this work is to explain the mechanisms behind galling and establish factors how it can be reduced. The focus of this work is on the influence of tool material for minimum risk of galling. Experimental tool steels alloyed with nitrogen were designed and manufactured for systematic tribological evaluation. Reference tool materials were conventional cold forming tool steels and coated tool steels. The sheet material was austenitic stainless steel AISI 304, which is sensitive for galling. A variety of lubricants ranging from low to high viscous lubricants were used in the evaluation. The properties of the tool materials were characterized analytically and their tribological evaluation included industrial field tests and several laboratory-scale tests. The testing verified that nitrogen alloying has a very positive effect for improving galling resistance of tool steels. Tool lives comparable to the coated tool steels were achieved even with low viscous lubricants without poisonous additives. The hypothesis used for the explanation of the positive effect of nitrogen alloying is based on the critical local contact temperature at which the lubrication deteriorates. Therefore, the contact mechanism at the tool-sheet interface and the local energy formation were studied systematically. Theoretical considerations complemented with FEA analysis showed that a small size of hard particles with a high volume fraction gives low local contact loads, which leads to low frictional heating. Also, an even spacing between the hard particles and their frictional properties are of importance. Nitrogen alloyed tool steels have these properties in the form of small carbonitrides. The finding of this work can be applied to a wide range of applications that involve sliding metal contacts under severe tribological loading.

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Maloney, Soren E. "Acoustics and manufacture of Caribbean steelpans." Thesis, University of Cambridge, 2011. https://www.repository.cam.ac.uk/handle/1810/238665.

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The Caribbean steelpan is a pitched percussion instrument that originated in Trinidad and Tobago during the Second World War. Despite several research initiatives to improve the making of this relatively new instrument, several areas remain unaddressed. This thesis presents new approaches to help improve the making of the instrument. These approaches are situated in the production, vibration and material aspect of the steelpan. A novel sheet forming technology termed Incremental Sheet Forming (ISF) is applied to the production of miniature steelpan dishes. The thickness distribution in the wall of the ISF dishes is compared to the wall thickness distribution in a traditionally formed steelpan dish and a wheeled dish. Unlike traditional forming and wheeling, ISF produces stretching in only a portion of the walls of the formed dishes. Multi-pass ISF is used to extend the stretched zone but this extension is minimal. A break even analysis is also applied to investigate the fiscal viability of ISF application to the production of miniature and full size steelpan dishes. The application of ISF to steelpan making is found to be commercially profitable but could be jeopardised by the tuning stage of the steelpan making process. A preliminary study on the effect of impact on tone stability is conducted on a pair of notes on a fullsize steelpan and detuning is found more likely to occur by repeated impact of the note at its centre. Mode confinement in test-pans is also investigated. ISF is used to produce miniature test-pans with test-notes that are geometrically identical to notes on full size pans. It is possible to confine modes by varying the curvature of the bowl surrounding the test-note. The number of localised modes in the test-note increases as the radius of curvature of the surrounding bowl increases. The natural frequency of the first confined mode in the test-notes is sensitive to material springback in ISF and the mechanism of confinement appears to be due to the change in geometry that occurs between the flat test-note region and the bowl wall. This control of mode confinement may find use in future efforts to completely or partially automate the steelpan making process. Material damping and mechanical properties in low-carbon steel used to produce steelpans are researched. Damping and mechanical properties are extracted from low-carbon steel that is subjected to identical stages to the steelpan production process. Material damping trends suggest that an annealing temperature between 300°C and 400°C would be appropriate for the heat treatment of steelpans. Air-cooled and water-quenched low-carbon specimens exhibit comparable damping trends. Hardness increases in cold formed low-carbon specimens is attributed to strain hardening and not strain ageing. Investigation of damping trends and mechanical properties in ultra low bake-hardenable and interstitial-free steels reveals that a wider range of low-carbon steels may be suitable for steelpan making.

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Daleffe, Anderson. "Fabricação de próteses cranianas personalizadas em chapas de titânio através da estampagem incremental." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/114468.

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O objetivo deste trabalho é fabricar próteses cranianas personalizados de baixo custo, em chapa de titânio puro. A fabricação antecipada do implante de acordo com as características do paciente permite ao cirurgião estudar e planejar a cirurgia com maiores possibilidades de atingir o resultado esperado, a personalização contribui para o resultado estético e funcional do implante, já que considera a anatomia de cada paciente, o custo baixo permite que um maior número de pessoas possam ser beneficiadas. Os experimentos práticos iniciam-se com aquisição de imagens tomográficas computadorizadas de um crânio defeituoso, reconstruiu-se digitalmente em CAD o crânio com defeito e também a reparadora (implante). A fabricação do implante em chapa de titânio puro grau 2 foi realizada por estampagem incremental, processo de baixo custo e que permite a fabricação customizada de peças. Foram comparadas as dimensões entre o modelo CAD e o modelo físico do implante. A partir da imagem tomográfica também foi gerado o modelo CAD do crânio fraturado e foi feita a usinagem do mesmo em madeira para a realização do teste funcional do implante onde foi comprovada a funcionalidade do mesmo, indicando a eficiência dos recursos e parâmetros utilizados. A ferramenta utilizada para a estampagem incremental foi fabricada em aço SAE 4340 com ponta intercambiável de titânio puro e o lubrificante utilizado no processo foi a base de gordura animal para evitar a contaminação da prótese. Foi feito o tratamento térmico de alivio de tensões na prótese estampada para manter as dimensões geométricas após o corte da prótese, melhoria na rugosidade superficial e biocompatibilidade do titânio. Após o tratamento térmico foram feitas análises na rugosidade e teste de molhabilidade no implante, onde os resultados mostraram que a prótese tratada termicamente muda as características biomecânicas. Para analise da geometria do implante foi feito uma varredura por escâner e comparação com o modelo CAD da prótese.
The work main objective is manufacture custom cranial implants with low cost, in titanium pure sheet. The prior implant fabrication according with the characteristics of the patient allow surgeon to study and planning surgeries with greater possibilities to achieve expected results. The customization helps for esthetic and functional results of implant, because regards the anatomy of each patient, the low cost allow the most people receive benefits. Practical experiments began with acquisition of computed tomographic images of a defective cranium, rebuilt the implant and this cranium in CAD images. Implant manufacture in titanium sheet pure grade 2, was performed with incremental forming, this process have low cost and enables to produce custom pieces. The implant dimensions been compared between the CAD Model and Physic Model. Starting with the tomographic image was generate the CAD Model of fractured cranium, and was make a machining the same in wood for realization of functional implant test, which was confirmed the same functionality, indicating resource efficiency and the parameters used. The tool used for sheet forming been manufactured in SAE 4340 steel with interchangeable point of pure titanium, and the lubricant used in the process has been the basis animal grease to avoid the implant contamination. Heat treatment was done to reduce the relief of stresses at the implant formed to maintain the geometric dimensions after the implant cut, superficial roughness better and titanium biocompatibility. After heat treatment, the average roughness analyzes performed and wettability test in the implant, witch results shows the treated prosthesis changes the biomechanical characteristics. For analysis of the implant geometry, was used a scanner and compared with the CAD model of the prosthesis.

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Lucca, Gustavo dos Santos de. "Análise de forças durante processo de estampagem incremental com o auxílio de extensometria." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/131049.

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O presente trabalho possui o objetivo de avaliar a aplicabilidade da metrologia em uma ferramenta de estampagem incremental de chapas. Para o estudo foi confeccionada uma ferramenta de estampagem com rebaixos em seu corpo cilíndrico para a fixação dos sensores que mediram a deformação relativa. As análises apresentadas nesta pesquisa representam os cuidados e processos necessários ao uso de extensômetros aliado a um processo de fabricação mecânica. No presente estudo define-se a calibração de um sistema de medição da deformação superficial da ferramenta de estampagem com auxílio da Extensometria. Para validar os resultados obtidos pelos métodos da instrumentação das medidas das deformações e forças no processo de estampagem incremental foram utilizados os métodos de Cálculos Analíticos e Simulação Numérica por meio de softwares de Elementos Finitos. No método de medida se considerou parâmetros que podem comprometer os valores medidos tais como a medida da temperatura utilizando equipamentos termovisor. Além disso, foram realizados 04 (quatro) ensaios preliminares com o intuito de avaliar a medição de forma satisfatória nos eixos X e Y do processo de estampagem incremental, efetuando análises das forças nesses eixos em tração e compressão. A estampagem incremental ocorreu por meio de um total de 09 (nove) Ensaios variando-se ângulo de parede (ψ) e espessura das chapas (s0). Os experimentos baseiam-se na variante de estampagem incremental denominada Estampagem Incremental de Ponto Simples (SPIF – Single Point Incremental Forming). Para a execução dos testes práticos foram utilizados recursos de hardware como Ponte Wheatstone, extensômetros, Termovisor, Centro de Usinagem CNC, matriz incremental, ferramenta de estampagem incremental e um dispositivo prensa chapas. Além de recursos de software CAD/CAM, DAQ (Data Acquisition System), Análise de Elementos Finitos. E recursos de cálculos analíticos como forma comprobatória de resultados. A partir dos procedimentos executados junto com aparato tecnológico foi possível efetuar as análises e medições das forças na ferramenta de estampagem incrementa com referência aos eixos X e Y. Demonstrando neste a aplicabilidade de extensometria para leitura e análise de forças no processo de ISF.
This present work has the objective of assessing the applicability of instrumentation science in an incremental forming tool. For this study was made a tool with recesses on its cylindrical body as a means of fixing the strain sensors. The study presented demonstrate some of the warning and processes required the use of Strain Gages combined with a mechanical manufacturing process. In the present study is defined as an acceptable calibration measuring system with the aid of Extensometry. To validate the results obtained by the methods of instrumentation measurements of the deformations and forces in incremental sheet forming process were used Analytical Calculations and Numerical Simulation using Finite Elements. The measurement method was considered parameters that can compromise the measured values such as temperature measurement devices using thermometer. In addition, we conducted four (04) preliminary tests in order to evaluate the measurement system in satisfactory form with measured variables such as X and Y axes. We analyses the traction and compression forces in both axes. After the preliminary step, was performed a total of nine (09) tests with incremental sheet forming process, varying wall angle (ψ) and the thickness (s0). The experiments are based on the Single Point Incremental Forming - SPIF. For the implementation of the practical tests were used hardware resources such as CNC Machining Center, Wheatstone Bridge, Strain Gauges, Thermal Imager, incremental matrix and incremental forming tool. Besides, we used softwares such as CAD/CAM, DAQ (Data Acquisition System) and Finite Element Analysis. From the technological procedures perform with apparatus was possible do carry out the analyzes and measurement of forces in incremental sheet forming tool increases about to the axes X and Y. Demonstrating the applicability of the extensometry for reading and analyzing forces in the ISF process.

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Al-Obaidi, Amar Baker Salim. "Induction Assisted Single Point Incremental Forming of Advanced High Strength Steels." Universitätsverlag der Technischen Universität Chemnitz, 2018. https://monarch.qucosa.de/id/qucosa%3A31527.

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Induction Assisted Single Point Incremental Forming (IASPIF) is a die-less hot sheet metal forming. The IASPIF does not apply characteristic complex tooling like those applied in deep drawing and bending. In this thesis, induction heating was used to heat up the sheet while simultaneously forming with a tool. The research goal is to improve the formability of high strength steels by heating. The IASPIF consists of non-complicated set up that allows induction heating to be utilized through the coil inductor moved under the sheet and synchronized with the forming tool that moves on the upper side of the sheet. The advanced high strength steel alloys, DP980, DP600 and 22MnB5 steels, were investigated. The influence of induction heating on formability was evaluated by the maximum wall angle that can be achieved in a single pass. Additionally, tool diameter and tool feed rate was also varied. The most influencing parameters were tool feed rate, induction power, and the profile depth. A new forming strategy was also developed by control the heating temperature through coupling the formed profile depth with a successively increased tool feed rate. The forming forces of DP980 steel sheet, were reduced from 7 kN to 2.5 kN when forming process was performed at room and elevated temperature, respectively. Stretching stresses were developed during forming process causing a high reduction in the resulting wall part thickness. New findings in this investigation were the reverse relationship between the step-down depth and the thickness reduction percentage. The smaller the tool diameter, the better was the formability. The finite element simulation of the investigated forming process showed that the increase in heating temperature has a direct effect on rising the plastic strain from 0.2 at room temperature to 1.02 at 800 ◦ C. The maximum true strain achieved in the resulting wall part thickness was determined by FEM simulations and validated with experimental trials. The part shape accuracy was measured and the highest deflection was founded when the part was formed by the highest step-down depth. Moreover, the minimum deflection in the part shape was achieved by utilizing a high induction power in the experiments. Finally, the resulting mechanical properties of the 22MnB5 alloy sheet material were tailored during IASPIF. For this purpose, the sheets were locally heated by induction during the forming process and subsequently quenched at different rates. As a result, the produced tailored parts consist of three different regions, which consist of a ductile, transitional and hardened region. The proposed procedure allows forming and quenching at the same time without transfer and thus, process time was reduced.
Die induktionsgestützte, inkrementelle Blechumformung (englisch: Induction Assisted Single-Point Incremental Forming IASPIF) ist Warmumformprozess, bei dem keine komplexen Werkzeuge wie beim Tiefziehen und Biegen benötigt werden. Inhalt dieser Arbeit ist die inkrementelle Umformung eines Bleches mit gleichzeitig ablaufender induktiver Erwärmung. Das Forschungsziel bestand in der Verbesserung der Umformbarkeit von hochfesten Stahlwerkstoffen wie DP600, DP980 und 22MnB5 durch eine gezielte partielle Erwärmung. Der prinzipielle Aufbau des Versuchsstandes besteht aus einem Spuleninduktor, der unterhalb des umzuformenden Blechs platziert ist, und der synchron mit dem Werkzeug – einem Drückdorn – während des Umformvorganges verfährt. Ein wesentlicher Untersuchungsschwerpunkt bestand in der Ermittlung der Einflussgrößen auf den untersuchten IASPIF-Prozess. Für die Bewertung der Umformbarkeit wurden hierbei der maximal erreichbare Teilwandwinkel und die Profiltiefe, die in einem Umformdurchgang herstellbar waren, ermittelt und ausgewertet. Darüber hinaus konnten im Rahmen der Arbeit die Induktionsleistung des Generators, der Werkzeugdurchmesser und die Werkzeugvorschubgeschwindigkeit als relevante Prozessparameter identifiziert werden. Im Ergebnis der durchgeführten Untersuchungen zeigten die Werkzeugvorschubgeschwindigkeit und die Induktionsleistung einen wesentlichen Einfluss auf die erreichbare Profiltiefe. Aufbauend auf den erzielten Ergebnissen konnte eine prozessangepasste Umformstrategie entwickelt werden, bei der eine konstante Erwärmungstemperatur durch das Koppeln der momentanen Profiltiefe mit einer sukzessiv steigenden Werkzeugvorschubgeschwindigkeit erreicht wird. Weiterhin ließen sich die Kräfte bei der Umformung eines Stahlbleches aus DP980 von 7 kN (bei Raumtemperatur) auf 2,5 kN (bei erhöhter Temperatur) reduzieren. Aufgrund des mit einem Streckziehvorgang vergleichbaren Spannungszustandes während des Umformprozesses war eine starke Verringerung der resultierenden Wanddicke zu beobachten. Als neue Erkenntnis in dieser Untersuchung konnte die umgekehrte Beziehung zwischen der Zustelltiefe und dem Dickenreduktionsprozentsatz abgleitet werden. Aus der Finite - Elemente - Simulation des vorgestellten Umformprozesses wurde erkennbar, dass die Erhöhung der Erwärmungstemperatur einen direkten Einfluss auf die plastische Dehnung von 0,2 (bei Raumtemperatur) auf 1,02 (bei 800 °C) hat. Mittels der numerischen Simulation und der nachfolgenden experimentellen Validierung erfolgte darüber hinaus die Bestimmung der maximalen wahren Dehnung, die in der resultierenden Wanddicke erreicht wurde. Bei den Versuchen mit der größten Zustellung ließ sich durch die Bestimmung der Teileformgenauigkeit die höchste Abweichung von der Sollgeometrie CAD Modell feststellen. Abschließend wurde nachgewiesen, dass der IASPIF Prozess auch zur Einstellung maßgeschneiderter Bauteileigenschaften wie der resultierenden mechanischen Eigenschaften des Blechmaterials aus 22MnB5 einsetzbar ist. Zu diesem Zweck wurden die Bleche während des Umformprozesses lokal induktiv erwärmt und anschließend zur Einstellung des gewünschten Gefüges bei unterschiedlichen Abkühlgeschwindigkeiten abgeschreckt.

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Arruda, Rodrigo Patrício de. "Estampagem incremental na conformação de chapas para fabricação de coletores solares planos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/118859.

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Este trabalho busca alternativas para fabricação de coletores solares planos aplicando técnicas inovadoras em conformação de chapas metálicas. O objetivo é desenvolver um processo de fabricação flexível para placa absorvedora, empregando a técnica da Estampagem Incremental. Esta técnica utiliza uma matriz de suporte de PU, um prensa-chapas e um pequeno punção em conjunto com um centro de usinagem CNC. A Ferramenta utilizada consiste um punção de ponta esférica de fácil fabricação que "desenha" o canal de passagem da água diretamente na chapa, promovendo uma deformação pontual e progressiva. Para compor o canal utilizou-se a técnica de solda por atrito (Friction Stir Welding) com uma ferramenta simples que aproveita o mesmo ferramental da estampagem incremental em um “set-up” rápido da CNC. Foram utilizadas chapas de alumínio de 1mm de espessura. O novo coletor apresenta uma eficiência aprimorada em comparação aos fabricados pelo método tradicional, com uma geometria que favoreça a área de contato com a água. Este processo permite uma formidável flexibilização, viabilizando a produção de pequenos lotes e tornando possível produzir uma enorme variedade de produtos e componentes de geometrias complexas a partir de um ferramental simples e tempos de “set-up” reduzidos.
This work searches alternatives for solar energy collectors manufacture, applying new technologies of sheet metal forming. The objective is to develop a flexible fabrication process for the absorber sheet, using Incremental Sheet Forming. It consists in a PU support die, a blank holder and a small tool, applied in a CNC machine Center. The tool consists in a spherical edge punch of easy fabrication that “draws” the water channel directly into the sheet, promoting a punctual and progressive deformation. To compose the channel, it was used a second sheet jointed by Friction Stir Welding technique, with a simple tool that uses the same tooling of the Incremental Forming in a quick setup of the CNC. Aluminum sheets of 1mm tick were used. It is expected that this new collector panel should improve the thermal efficiency when compared to the traditionally fabricated, and with a geometry that benefits the contact area with the water. This process allows a formidable flexibilization, making the low volume production feasible, allowing the production of a great variety of products and components with complex geometries from simple tooling and reduced setup times.

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Lora, Fabio Andre. "Avaliação das deformações no aço DC04 quando submetido ao processo híbrido de estampagem incremental posterior ao processo convencional." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/103731.

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O presente trabalho aborda a aplicação de processos combinados de estampagem, processo convencional e incremental em uma mesma chapa metálica. Essa combinação é denominada de processo de estampagem híbrido. Tal processo é realizado através da fabricação de uma pré-forma pelo processo convencional de estampagem, seguido da manufatura pelo processo incremental. O objetivo principal é analisar o comportamento das deformações ocorridas na geratriz, o que até então só havia sido analisado separadamente, sem um aprofundamento aplicado ao processo híbrido. As deformações ocorridas no processo convencional determinam os caminhos de deformações nos elementos da geratriz, influenciando diretamente as deformações geradas pela estampagem incremental. Para alcançar os objetivos, experimentos foram realizados com o material aço DC04, sendo divididos em duas etapas: a estampagem incremental em linha reta e após o processo de estampagem híbrido. A estampagem incremental em linha reta foi realizada para avaliação do material em relação a diferentes estratégias incrementais e às máximas deformações. No processo híbrido, as deformações da estampagem convencional foram realizadas em três direções com graus de deformações diferentes. Na etapa incremental do processo híbrido foi adotada a estratégia de pirâmide com diferentes inclinações de parede nas amostras. Nos experimentos, foram analisadas as deformações verdadeiras, geometrias finais e redução de espessura das amostras. A simulação numérica é uma ferramenta computacional que foi utilizada para comparação e correlação com os dados dos experimentos físicos. Os critérios de falha ou parada das simulações são dependentes dos dados do material (curva limite de conformação) e/ou dos experimentos físicos realizados (profundidade de ruptura). No desenvolvimento da estampagem incremental em linha reta, o punção de ponta hemisférica com diâmetro de 30mm e 1mm de incremento por etapa apresentou as maiores deformações máximas (1,03). No processo de estampagem híbrido, as amostras com pré-deformações de embutimento profundo tenderam a não influenciar as deformações incrementais finais. As amostras com pré-deformações planas foram diretamente proporcionais às deformações máximas incrementais. Já as com pré-deformações de estiramento biaxial influenciaram as deformações incrementais conforme o grau da pré-deformação.
The present work approaches the application of combined forming processes, and conventional and incremental sheet forming processes in the same metal sheet. This combination is denominated hybrid forming processe. This process is done through the manufacture of a pre form by conventional forming process, followed by incremental sheet forming. The main objective is to analyze the behavior of strains occurred in the blank, which until now was only studied separately, without a deepening study applied to hybrid process. The pre strains occurred in the conventional process determine the strain paths in the blank elements, directly influencing the strains produced by the incremental process. To reach these objectives, experiments with DC4 steel were done, and were separated into two stages: first, a test of incremental sheet forming in a straight line, and, after, the hybrid forming process. The incremental sheet forming in straight line was done to evaluate the material in relation to different incremental strategies in this process and to maximum deformations. In the hybrid process, the conventional process deformations were done in three directions with distinct strain rate. In the incremental stage, the pyramid strategy was adopted with different wall inclinations of samples. In the experiments, the true strains, the final geometries and the samples thickness reduction was analyzed. The numerical simulation is a computational tool that was used for the comparison and correlation with the data of the physical experiments. The failure criterion or stopped simulations depend of the material data (Forming Limit Curve) and/or on the physical experiments done (depth of rupture). In the development of the incremental forming in straight line, the hemispherical-headed punch with diameter of 30 mm and 1 mm of increment per step presented the higher maximum strains (1,03). In the hybrid process, the deep drawing samples with pre-strain did not tend to influence the final incremental strains. The samples with plane pre-strain were directly proportional to the maximum incremental strains. Tthe samples with pre-strain biaxial, on the other hand, influenced the incremental strains according to the degree of pre-strain.

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Zachén, Esbjörn. "Extraction of tool reaction forces using LS-DYNA and its use in Autoform sheet metal forming simulation." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-17886.

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In product development there is still potential to decrease lead times with faster and more accurate simulations. The objective of this thesis was to study whether Finite Element (FE) simulations using explicit LS-DYNA to extract reaction forces from sheet metal forming tools during forming, could be used to improve existing FE models in sheet metal forming software AutoForm.To begin with, the solid CAD-model of the stamping dies were meshed with tetrahedral elements in CATIA and imported into LS-DYNA. In combination with sheet mesh and milling surface meshes from AutoForm, an explicit model was realized. Contacts between sheet mesh and milling surface meshes used the so-called sheet forming contact. The resulting reaction forces were extracted and used in a simulation using the AutoForm software. Resulting simulation was compared to a scan of the physical sheet metal after forming.The direct transfer of reaction forces from LS-DYNA to AutoForm did however not result in the same pressure distribution in AutoForm. The AutoForm simulations using results from LS-DYNA were slightly worse than standard AutoForm simulations.Further work is needed to try and perhaps implement an implicit solution after an initial explicit solution.
Inom produktutveckling finns möjligheter att förkorta ledtider genom snabbare och mera korrekta simuleringar. Syftet med detta arbetet var att undersöka huruvida resultat från explicit LS-DYNA kunde användas för att förbättra nuvarande plåtformningssimuleringar i AutoForm.Den solida CAD-modellen av verktyget meshades med tetraediska element i CATIA och importerades till LS-PrePost, tillsammans med fräsytsmeshar och plåtmesh från AutoForm. Kontakter etablerades mellan plåt och fräsytsmeshar med så kallad sheet forming contact. Modellen löstes sedan explicit. Resulterande reaktionskrafter på plåthållare exporterades till AutoForm och implementerades där. Resulterande simulering jämfördes mot en inskannad fysisk plåt efter plåtformning.Direkt implementering av reaktionskrafter på plåthållaren i AutoForm gav resultat som avvek mer mot inskannad plåt än nuvarande simuleringsstrategi. Direkt implementering av reaktionskrafter gav heller inte en tryckfördelning som liknade den som rapporterades av LS-DYNA.Mer arbete krävs för att om möjligt implementera en implicit lösning efter en initial explicit lösning.

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Schreiber, Rafael Gustavo. "Estampagem incremental e soldagem FSW para fabricação de coletor solar." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/183075.

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Este trabalho apresenta um modelo inovador de coletor solar plano, com placa absorvedora fabricada por Estampagem Incremental e Soldagem FSW (Friction Stir Welding). Esta placa absorvedora é constituída de duas chapas de alumínio AA1200-H14 com espessura de 1 mm, estampadas e soldadas em simetria, a fim de que na união das chapas sejam deixados canais para passagem de água. Neste estudo foi realizada a caracterização do material por Ensaio de Tração e Ensaio Nakajima. Para determinação dos parâmetros de Estampagem Incremental foram realizados 16 experimentos com ferramenta de diâmetro df = 9,5 mm, variando a rotação de N = 50 rpm a 800 rpm e o incremento vertical de Δz = 2 mm a 0,2 mm, mantendo o avanço em = 250 mm/min. E também foram realizados 3 experimentos com ferramenta df = 22 mm, variando o incremento vertical de Δz = 2 mm a 0,5 mm, mantendo a rotação em N = 50 rpm e o avanço em = 250 mm/min. Para determinação dos parâmetros de Soldagem FSW foram realizados 4 experimentos com ferramenta de ombro de diâmetro 8 mm e pino roscado M3x0,5, mantendo a rotação em N = 1500 rpm e variando o avanço entre = 100 mm/min a 400 mm/min. Em seguida foi fabricado um protótipo de placa absorvedora de coletor solar com área de 0,12 m². Nos experimentos realizados foi constatado que é possível obter maiores deformações na Estampagem Incremental do que na Estampagem Convencional e que as deformações são mais elevadas quando se utiliza menores diâmetros, maiores rotações e menores incrementos verticais da ferramenta. Na Soldagem FSW não foi constatada influência na qualidade do cordão de solda em relação à variação do avanço da ferramenta. Neste estudo também se verificou que é possível fabricar protótipos de placas absorvedoras de coletores solares pelos processos de Estampagem Incremental e Soldagem FSW. No entanto, para coletores em tamanho comercial, novos estudos são necessários para melhorar a forma de fixação das chapas durante a Soldagem FSW.
This work presents an innovative model of flat plate solar collector, with absorber plate manufactured using Incremental Sheet Forming (ISF) and Friction Stir Welding (FSW). This absorber plate consists of two AA1200-H14 aluminum sheets with a thickness of 1 mm, stamped and welded in symmetry, in order to leave channels for the passage of water. In this study the characterization of the material by Nakajima Test and Traction Test was performed. In order to determine the parameters of ISF, 16 experiments were performed with a tool of diameter df = 9.5 mm, varying the rotation speed of N = 50 rpm at 800 rpm and the step down of Δz = 2 mm to 0.2 mm, maintaining the feed rate at = 250 mm/min. Also, 3 experiments with tool df = 22 mm were performed, varying the step down of Δz = 2 mm to 0.5 mm, maintaining the rotation speed at N = 50 rpm and the feed rate at = 250 mm/min. For determination of FSW parameters, 4 experiments with 8 mm diameter shoulder tool and M3x0.5 pin were performed, maintaining the rotation speed at N = 1500 rpm and varying the feed rate from = 100 mm/min to 400 mm/min. A prototype solar collector absorber plate with a 0.12 m² area was then manufactured. In the experiments carried out, it was found that it is possible to obtain greater deformations in the ISF than in the Conventional Stamping and that the deformations are higher when using smaller diameters, higher rotations and smaller step downs of the tool. In FSW, no influence was observed in the quality of the weld bead in relation to the variation of the tool feed rate. In this study it was also verified that it is possible to manufacture prototypes of solar collector absorber plates by the processes of ISF and FSW. However, for commercial size collectors, further studies are needed to improve the way the plates are fixed during FSW.

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Keum, Young Tag. "Compatible description of tool surfaces and FEM meshes for analyzing sheet-forming operations in two- and three dimensions /." The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487681148540439.

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Andersson, Oscar. "Influence of primary precipitate shape, size volume fraction and distribution in PM tool steels on galling resistance." Thesis, Karlstads universitet, Institutionen för ingenjörsvetenskap och fysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-37813.

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In sheet metal forming (SMF), the major failure reason is galling. Galling is a process of different wear stages that leads to destruction of both the forming tool and the sheet metal working piece and is, because of that, of big economic importance for the SMF industries. Therefore, investigations and researches about how tool steels microstructure affect the tool steels galling resistance is of high priority. In the present work, different carbide properties were studied to find out how their properties affected the tool materials galling resistance. The investigated carbide properties were: Shape and size of the carbides  Carbide volume fraction Carbide distribution in the microstructure The investigation included three tools, all made of the PM tool steel S390, that were heattreated differently in order to achieve different carbide properties but still maintain the same hardness. The tools were galling tested in a slider-on-flat-surface (SOFS) tribometer to determine their galling resistances. In a scanning surface electron microscope (SEM) the tools galling marks were analyzed to find explanations for the SOFS tribometer results and the connection to the tools different carbide properties. The investigations most galling resistant tool was the tool that had the microstructure with largest carbides which were distributed at grain boundaries and the second highest carbide volume fraction among the investigated tools.

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Maqbool, Fawad [Verfasser], and Markus [Gutachter] Bambach. "Targeted generation and suppression of the deformation mechanism and residual stresses in incremental sheet forming to improve the geometric accuracy / Fawad Maqbool ; Gutachter: Markus Bambach." Cottbus : BTU Cottbus - Senftenberg, 2021. http://d-nb.info/1238598056/34.

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Ben, Hmida Ramzi. "Identification de lois de comportement de tôles en faibles épaisseurs par développement et utilisation du procédé de microformage incrémental." Thesis, Besançon, 2014. http://www.theses.fr/2014BESA2042.

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La miniaturisation des composants est aujourd’hui un challenge mondial. La fabrication de ces composants est rendue difficile par un certain nombre de phénomènes liés aux effets d’échelle. Il est ainsi nécessaire de répondre à ces contraintes de réduction d’échelle en termes de conception, de réalisation et de fonctionnement de ces systèmes. Cette étude aborde la problématique de la miniaturisation des procédés et plus particulièrement du procédé de micro-formage incrémental « mono-point » (micro-SPIF) à travers des études expérimentales et numériques. Le micro-formage incrémental de tôles est présenté comme une approche intéres sante de fabrication de structures minces. La géométrie désirée est assurée par la trajectoire d’un outil imposant une déformation locale sur la tôle serrée en son contour. Dans un premier temps, une approcheexpérimentale consistant à analyser le comportement mécanique des éprouvettes en alliage de cuivre avec différentes tailles de grains par des essais de traction a été proposée. L’interaction entre la géométrie et la microstructure est évaluée à l’aide du ratio de l'épaisseur par la taille moyenne de grains Φ=t/d. Un pilote de formage incrémental « mono-point » instrumenté a été également développé. Une campagne d'essais expérimentaux de micro-SPIF a été ainsi réalisée sur des flans par différentes tailles de grains afin d'étudier les effets de la microstructure sur la géométrie, l’état de surface, la distribution des épaisseurs et sur l’évolution des efforts. Dans un second temps, un modèle paramétrique de type éléments finis simulant le micro-SPIF a été développé en langage MATLAB®. Le code de calculs LS-DYNA® a été utilisé pour simuler le procédé en adaptant une loi de comportement élastoplastique. Ensuite, les résultats obtenus en termes de géométrie,d’évolution de l’épaisseur et d’efforts de formage sont confrontés aux relevés expérimentaux afin de valider la procédure numérique. Dans un troisième temps, une loi élastoplastique endommageable décrivant les principaux phénomènes physiques intervenant durant le formage des métaux en grandes déformations a été présentée. Une procédure d'identification de cette loi basée sur une analyse inverse de l’effort au cours du procédé de micro-SPIF a été proposée et des tests de validation du modèle ont été discutés. Enfin, une analyse de l'identifiabilité locale basée sur un indice de multicolinéarité des fonctions de sensibilité est effectuée pour valider la procédure d’identification paramétrique et quantifier l’intérêt du procédé pour la caractérisation quantitative des tôlesminces en très grandes déformations
The miniaturization of components is now a world challenge. The manufacture of these componentsis difficult because of several phenomena related to the so-called size effect. It is thus necessary to fulfill theserequirements of scaling down in terms of design, implementation and operations. This study deals with theproblems of miniaturization processes, especially the “micro-Single Point" Incremental Forming process (micro-SPIF) through experimental and numerical studies. Micro-single point incremental forming process is presentedas an interesting approach for thin structures manufacturing. The desired geometry is provided by the tool pathrequiring a local deformation in a sheet clamped along its contour. Firstly, an experimental approach consistingin analyzing the mechanical behaviour of copper alloy specimens with various grain sizes by tensile tests hasbeen proposed. The interaction between the geometry and the microstructure is evaluated using the ratio of thethickness by the average grain size Φ=t/d. An instrumented micro-SPIF device was also developed. A set ofsingle point incremental sheet forming experimental tests were conducted on blanks with several grain sizesusing two forming strategies in order to study the effect of microstructure on the geometry, the surface topology,the thickness distribution and the forming forces evolutions. Secondly, a finite element parametric model capableof simulating the micro-SPIF process was developed in MATLAB® language. The commercial LS-DYNA® codewas used to simulate this process using an elastic-plastic constitutive law. Then, the results obtained in terms ofgeometry, thickness evolution and forming forces are compared with the experimental results in order to validatethe numerical procedure. Thirdly, an elastic-plastic damage model describing the main physical phenomenainvolved during metal forming by large deformation was presented. An identification procedure of thisbehaviour law based on the inverse analysis of the axial forming force during micro-SPIF process was proposedand several validation tests of the model were discussed. Finally, local identifiability analysis based on an indexof multicollinearity of the sensitivity functions was performed in order to validate the parameters identificationprocedure and quantify the advantage of the process for quantitative mechanical behaviour characterization ofthin metal sheets at large strains

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Furlanetti, Michael. "Estudo do comportamento das deformações em flanges obtidos pelo processo de estampagem incremental através de elementos finitos e projeto de um suporte modular." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18145/tde-30112017-165852/.

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A estampagem incremental é um processo de deformação incremental de chapa que pode ser classificado em três modos distintos: estampagem incremental sem matriz, estampagem incremental com matriz parcial e estampagem com matriz total. A deformação ocorre devido ao contato entre a ferramenta e a chapa, localmente e progressivamente, ao longo de uma trajetória pré-definida. A chapa permanece presa a suportes que fixam as suas extremidades de maneira a impedir os deslocamentos provocados pela passagem da ferramenta. A primeira parte deste trabalho compreende estudos em elementos finitos, usando o software LS-Dyna, sobre a trajetória das deformações na estampagem incremental para a fabricação de flanges em chapas previamente furadas de liga de alumínio AA1050. Foram realizados testes de contato e de linha que permitiram definir parâmetros da simulação. Os resultados para as deformações foram confrontados com os resultados obtidos experimentalmente por outros autores e permitiram verificar o comportamento das deformações nos flanges. As deformações crescem montonicamente até os valores máximos. Este resultado confirma a teoria de que na estampagem incremental de chapas a fratura ocorre sem o prévio aparecimento da estricção. A segunda parte deste trabalho trata do desenvolvimento de um suporte modular aplicável a estampagem incremental, tanto na sua variante sem matriz quanto com matriz, com o intuito de aumentar a flexibilidade do processo com relação à geometria da peça a ser deformada. Foi empregada a técnica de análise de valor objetivando alcançar a melhor funcionalidade do sistema. Como resultado foi obtido um suporte modular que atende os requisitos de rigidez, flexibilidade, modularidade, agilidade na troca da chapa a ser deformada e simplicidade construtiva.
The sheet incremental forming can be classified into three basic configurations, depending on the number of contact points between the sheet, tool and die (when present). Single incremental forming (absence of specific dies) and two point incremental forming (presence of a partial or full die) can be distinguished. The process makes use of a simple, low-cost, hemispherical tipped tool to precisely and progressively shape a blank into a metal sheet along a predefined tool path. The sheet is fixed onto the rig to prevent lateral displacements caused by tool movement. The first part of this work includes studies about finite elements, using the LS-Dyna software, applied to deformation path in hole-flanging produced by incremental sheet forming. The investigation was carried out using aluminum alloy AA1050. Contact and line numerical results support simulation parameters choices. The results from the strains were compared with empirical ones obtained by other authors. The results showed the deformation mechanics behavior of the hole-flanging. The strain paths of hole-flanging produced by incremental sheet forming grew linearly and monotonically from the origin to the maximum achievable strains. This result confirms the absence of local necking along plane strain directions. The second part of this work deals with the development of a modular rig that can be applied to dieless, partial or total die single point incremental forming in order to increase the flexibility of the process concerning the geometry of the part to be deformed. The result was a modular rig with constructive simplicity and requirements of stiffness, flexibility and modularity when exchanging sheets.

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Kráčmar, Lukáš. "Výroba nástěnného držáku televizoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241723.

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This master’s thesis conducted within the master's degree focuses on the design of production for component, which is a wall-mount the TV. The blank is sheet steel DC03 and the annual production is 300,000 pieces. After exploring possible options of manufacturing was chosen compound tool. In the theoretical part were explored technology used cutting and bending. Further, the manufacturing process and tool design were made. The suitability of the solution was verified by economic evaluation.

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Vodák, Marek. "Návrh výroby plechu TV držáku." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-416645.

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This master’s thesis is focused on the design of the technology to produce a part of the TV bracket. The part is made of steel sheet with a thickness of 2.5 mm. The structural steel S235JR was chosen as the most suitable material with following powder coating. From the possible variants, the production by progressive forming tool was chosen with respect to production requirements and a series size of 30 000 pieces by year. The part will be made in seven steps in designed tool and the total required force is 1013 kN. The production will take place on a mechanical press PCK12 from Bliss-Bret with a maximum force of 1250 kN. The final price of the part is 39.4 Kč.

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Kvapil, Jan. "Návrh stroje pro stříhání a ohýbání vybrané součástky." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230631.

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KVAPIL Jan: Bending and cutting press machine for representativ part The Master´s thesis, which is developer in an undergraduate degrese in M-VSR, provides a brief overview and description of the cutting and bending technology. The thesis is carried out the calculation, which is essential for the design cutting and bending tools. Models and design are created in the software SolidWorks 2012. The Master´s thesis includes a general procedure after the award until after copy the parts on it.

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Šobáň, Pavel. "Výroba kotevního prvku." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231180.

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The wall clamp is used for attaching columns or pillars to a concrete foundation. It is made from structural steel 11 375 in the form of sheets with a thickness of 4 mm in the production run of 150 000 pcs/year. A combination of shearing and bending technologies in a progressive forming tool was selected from various options as the most appropriate. On the basis of structural and technological calculations, an instrument was designed, for which the technical documentation was elaborated. Due to the total forming force and work, the forming machine LDO 800 A/S from Šmeral Brno a.s. was selected as the manufacturing machine. The production cost per one part 53.66 CZK was determined using economic evaluation; based on the break even point, the production becomes profitable for the production run with the minimum number of 13 065 pcs.

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Vítek, Roman. "Výroba součásti "KRYT" plošným tvářením." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229385.

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The Master’s thesis written in the frame of studies branch Manufacturing Technology (2303T002) is submitting design of technology production of sheet metal cover. The part is made of sheet metal 1,5 mm thick. The material for the part is HC260LA (ZStE260). There are no special mechanical or dimensional accuracy demands for the part. According to production run (5 000 pcs. per year for 5 years), design complexity and machine accessories of submitter was proposed manufacturing the part by drawing technology with finish laser cutting. Forming tool is designed according with press Erfurt PKZZ 315. Thesis includes economical evaluation of elaborated technology with other variants of production.

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Ručka, David. "Konstrukce lisovacího nástroje pro součást z plechu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229681.

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The in the framework of Master’s Studies developed project presents a technology- proposal for the production of a pressing tool for the manufacturing of parts from the sheet steel DD13. On the basis of a literary survey of problems of the component manufacturing through shearing, bending and the studies of heat treatment and applications of covering coat and calculation, manufacturing in the phase-shearing tool was proposed. The press GERB EDELHOFF 80 t was selected as the working device.

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Lipka, Ondřej. "Výroba držáku antény sdruženým nástrojem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231054.

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This master’s thesis focuses on the concept of large-lot manufacturing of sheet metal component made from DC01 steel. Based on forethought, the method of compound tool combining shearing and bending was chosen. The theoretical part analyses used technologies in detail. In the next part specific course of manufacture was created and supplied with technological calculations. Based on all needed facts the tool was designed and after that forming machine, LDC 160 crank press, was chosen. At the end the usability of designed concept was confirmed with economical calculations.

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Svobodová, Helena. "Návrh výroby kotvícího prvku solárního kolektoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318398.

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In this master's thesis the proposal of the production technology of component – solar collector anchor element from steel 1.0038 (11 375) quality, 5 mm thickness is solved. For the manufacturing of the assigned part the shearing and bending technology and a progressive forming tool including a suitable forming machine of 8,000 kN rated power is selected. The proposed method of production is laid down by a technical-economic evaluation with respect to the production series of 150,000 units per year. The solar collector anchor element serves to hold the frame for the solar vacuum tube collector. In the scope of this master's thesis, an assessment of the current production method, including the selection of a suitable semi-finished product for production, was also carried out and their optimization was proposed.

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Kratina, Patrik. "Výroba držáku uhlíku." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417061.

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This master´s thesis focuses on the concept of manufacturing of carbon brush holder, made of steel S235JRG (ČSN 11 343), with thickness of 1,5 mm. In order to reduce costs, it was decided to manufacture the holder with progresive stamping tool, which combines cutting, bending and edging operations in order to achieve specific part shape. Based on relevant calculations the mechanical press LEN 63 C was chosen. The production series was set at 50 000 pieces.

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Szyszka, Jörg, Dietmar Süße, and Christine Schöne. "CAE Methoden in der Einarbeitungsphase der Blechumformung." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-228301.

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Aus der Einleitung: "Um Kosten in der Produktentwicklung weiter zu minimieren und gleichzeitig die Qualität der zu fertigenden Produkte zu gewährleisten, nehmen virtuelle Methoden in der Produktentwicklung einen immer größeren Stellenwert ein (Stelzer & Eigner, 2009). An die Maßhaltigkeit von umgeformten Blechteilen werden ständig höhere Anforderungen gestellt. Die Ursachen für Maßabweichungen an gefertigten Blechteilen resultieren maßgeblich aus den Berechnungsmodellen, die das System Werkzeug-Blechteil-Umformmaschine bisher in der Virtuellen Produktentwicklung noch nicht vollständig und exakt abbilden können. Mehrere Zyklen händischer Änderungen an den Umformwerkzeugen sind heute noch die Regel. Dieser Prozess wird bei der Blechumformung als Einarbeitungsphase bezeichnet und wird von Spezialisten des Werkzeugbaus unter Nutzung von unscharfem Erfahrungswissen durchgeführt. Der Zyklus der manuellen Einarbeitungsphase im Bereich des Werkzeugbaus steht den wirtschaftlichen Forderungen zum schnelleren Serienanlauf und zur Kostensenkung entgegen. Hier kann die Verkürzung des Einarbeitungsprozesses dienlich sein."

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Dissertations / Theses on the topic 'Incremental sheet forming tool'

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