Готові списки джерел за темами / Plastiska deformationer

Зміст

Статті в журналах
Дисертації

Добірка наукової літератури з теми "Plastiska deformationer"

Автор: Grafiati

Опубліковано: 4 червня 2021

Оновлено: 5 лютого 2022

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Plastiska deformationer".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Статті в журналах з теми "Plastiska deformationer"

Nakajima, N., and E. R. Harrell. "Rheology of PVC Plastisol - VIII: Mechanism of Non-Linear Viscoelastic Behavior." Rubber Chemistry and Technology 76, no. 5 (November 1, 2003): 1074–90. http://dx.doi.org/10.5254/1.3547788.

Повний текст джерела

Анотація:

Abstract The mechanism of the strain-amplitude dependence (non-linearity) of viscoelastic properties of a PVC plastisol was examined. The range of amplitude was 0.02 to 10.24 and the range of frequency was 0.1 to 100 rad/s. The amplitude dependence of dynamic viscosity was very similar to its frequency dependence in that with the increase of amplitude or frequency it decreased first, reaching a minimum and then increased. In the preceding series of papers, the decrease of viscosity with the increase of frequency, i.e. pseudo-plasticity, was attributed to shear-induced phase separation into immobilized layer and mobile phase. In the present work, it is shown that the same mechanism is responsible for the decrease of viscosity with the increase of amplitude. The increase of viscosity with the increase of amplitude (after the minimum) is explained by the dilatation of the immobilized layer. Subsequently, the normal stress acting on the immobilized layer is calculated from the difference of the osmotic pressure between the mobile phase and immobilized layer. The shear deformation of the immobilized layer is estimated to be extremely small, although the deformation in the normal direction, i.e. the dilatation, is significant.

Стилі APA, Harvard, Vancouver, ISO та ін.

Yaqin, Rizqi Ilmal, Mega Lazuardi Umar, Sigiet Haryo Pranoto, Angger Bagus Prasetiyo, and Bambang Hari Priyambodo. "STUDI PERANCANGAN PISAU PADA MESIN PENCACAH PLASTIK MENGGUNAKAN FINITE ELEMENT ANALYSIS." JTT (Jurnal Teknologi Terapan) 7, no. 1 (May 19, 2021): 44. http://dx.doi.org/10.31884/jtt.v7i1.320.

Повний текст джерела

Анотація:

The amount of plastic waste each year will increase by 10% every year which is a problem for a country. Therefore, proper processing of plastic waste needs to be done. Before being processed into plastic waste processing, it is necessary to have a chopping process using a plastic chopping machine. The plastic chopping machine has an important component, namely the chopping knife. Before carrying out the knife manufacturing process, it is necessary to validate the design of the blade that is used with its loading. Model simulation using software is one way to quickly validate the model. This study aims to determine the effect of loading variations on stress, strain, deformation and safety factors of the model. The use of ANSYS R17.2 software is used to analyze the chopping machine knife model with a variation of 5kg / hour, 10kg / hour, 20kg / hour and 50kg / hour capacities. The result is that the stress, strain and deformation parameters have an increase in value with increasing loading variations. The greatest values of stress, strain and deformation are in the variation of 50kg / hour respectively 64.995 Pa; 336.76 and 56,358 x 10-11mm. The value of the safety factor for all variations of loading has a value of 15. The value of the safety factor means that the design of the plastic chopping knife is safe to use up to a loading of 50kg / hour

Стилі APA, Harvard, Vancouver, ISO та ін.

Setiyana, Budi, Imam Syafaat, Jamari Jamari, and DikJoe Schipper. "FRICTION ANALYSIS ON SCRATCH DEFORMATION MODES OF VISCO-ELASTIC-PLASTIC MATERIALS." Reaktor 14, no. 3 (February 3, 2013): 199. http://dx.doi.org/10.14710/reaktor.14.3.199-203.

Повний текст джерела

Анотація:

Understanding of abrasion resistance and associated surfaces deformation mechanisms is of primary importance in materials engineering and design. Instrumented scratch testing has proven to be a useful tool for characterizing the abrasion resistance of materials. Using a conical indenter in a scratch test may result in different deformation modes, like as elastic deformation, ironing, ductile ploughing and cutting. This paper presents the friction analysis of some deformation modes of visco-elastic-plastic behaving polymer materials, especially PEEK (poly ether ether ketone).In general, it is accepted that the friction consist of an adhesion and a deformation component, which can be assumed to be independent to each others. During a scratch test, the friction coefficient is influenced by some parameters, such as the sharpness of indenter, the deformation modes and the degree of elastic recovery. Results show that the adhesion component strongly influences the friction in the elastic and ironing deformation mode (scratching with a blunt cone), friction for the cutting deformation mode (scratching with a sharp cone) is dominantly influenced by the deformation component. From the analysis, it can be concluded that the adhesion friction model is suitable for ironing - elastic deformation mode and the deformation friction model with elastic recovery is good for cutting mode. Moreover, the ductile ploughing mode is combination of the adhesion and plastic deformation friction model. ANALISIS FRIKSI PADA BENTUK DEFORMASI AKIBAT GORESAN PADA MATERIAL VISKO-ELASTIK-PLASTIK. Pemahaman tentang ketahanan abrasi dan deformasi permukaan yang menyertainya merupakan hal yang penting dalam rekayasa dan disain material. Peralatan uji gores terbukti ampuh untuk menyatakan ketahanan abrasi dari material. Pemakaian indenter kerucut dalam uji gores akan menghasilkan beberapa bentuk deformasi seperti halnya deformasi elastik, penyetrikaan, plowing dan pemotongan. Paper ini menyajikan analisis friksi dari beberapa bentuk deformasi permukaan dari material visko-elastik-plastik, khususnya pada PEEK (poly ether ether ketone). Secara umum dinyatakan bahwa friksi terdiri dari komponen adhesi dan deformasi yang diasumsikan tidak bergantung satu sama lain. Selama uji gores, koefisien friksi dipengaruhi oleh beberapa parameter, seperti ketajaman indenter, bentuk deformasi dan pemulihan elastik. Hasil menunjukkan bahwa komponen adhesi sangat berpengaruh pada deformasi elastic dan penyetrikaan (uji gores dengan indenter tumpul), sedang untuk pemotongan (uji gores dengan indenter tajam) sangat dipengaruhi oleh komponen deformasi. Dari analisis dapat disimpulkan bahwa model friksi adhesi cocok untuk deformasi elastic dan penyetrikaan, sedang model friksi deformasi dengan pemulihan elastic, cocok untuk pemotongan. Selain itu, plowing merupakan kombinasi dari model friksi adhesi dan deformasi.

Стилі APA, Harvard, Vancouver, ISO та ін.

Santana, Elvis. "Congenital luxation of the knee: with regard to a case." Clinical Orthopaedics and Trauma Care 2, no. 2 (October 21, 2020): 01–04. http://dx.doi.org/10.31579/2694-0248/007.

Повний текст джерела

Анотація:

The congenital luxation of the knee is an unfrequent affection, existing many theories about it's appearance. In some cases, it is considered an isolated deformation although it is relativly frequent to associate it to other congenital malformations, such as the dysplasia on the development of the hip, feet deformities or dislocation of the elbow. The treatment of this kind of affection depends on the seriousness and flexibility of the fondness, having like therapeutic lines the placing of serial casts, by using Pavlik's armor or plastia of the four headed muscle on severe cases. We present a case of congenital luxation of the knee treated by the use of serial casts, with a favorable evolution.

Стилі APA, Harvard, Vancouver, ISO та ін.

Erkamp, R. Q., P. Wiggins, A. R. Skovoroda, S. Y. Emelianov, and M. O'Donnell. "Measuring the Elastic Modulus of Small Tissue Samples." Ultrasonic Imaging 20, no. 1 (January 1998): 17–28. http://dx.doi.org/10.1177/016173469802000102.

Повний текст джерела

Анотація:

Independent measurements of the elastic modulus (Young's modulus) of tissue are a necessary step in turning elasticity imaging into a clinical tool. A system capable of measuring the elastic modulus of small tissue samples was developed. The system tolerates the constraints of biological tissue, such as limited sample size (≤1.5 cm3) and imperfections in sample geometry. A known deformation is applied to the tissue sample while simultaneously measuring the resulting force. These measurements are then converted to an elastic modulus, where the conversion uses prior calibration of the system with plastisol samples of known Young's modulus. Accurate measurements have been obtained from 10 to 80 kPa, covering a wide range of tissue modulus values. In addition, the performance of the system was further investigated using finite element analysis. Finally, preliminary elasticity measurements on canine kidney samples are presented and discussed.

Стилі APA, Harvard, Vancouver, ISO та ін.

Skaržauskas, Valentinas, Dovilė Merkevičiūtė, and Juozas Atkočiūnas. "LOAD OPTIMIZATION OF ELASTIC-PLASTIC FRAMES AT SHAKEDOWN/PRISITAIKANČIŲ TAMPRIAI PLASTIŠKŲ RĖMŲ APKROVOS OPTIMIZACIJA." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 7, no. 6 (December 31, 2001): 433–40. http://dx.doi.org/10.3846/13921525.2001.10531769.

Повний текст джерела

Анотація:

In this article the theory of mathematical programming is used, composing improved mathematical models of nonlinear problems of frame loading optimization at shakedown and performing its numerical experiment. An elastic perfectly-plastic frame is considered. Frame geometry, material, load application places are considered known. Time independent load variation bounds are variable (history of loading is unknown). Mathematical model of load variation bounds optimization problem includes strength and stiffness constrains. The mentioned optimization load combines two problems. First problem is connected with the distribution of statically admissible moments at shakedown. This is a problem of residual bending moments analysis which is presented in two ways. In the first case it is formulated as a quadratic programming problem, where the objective function is non-linear, but the objective function of load optimization problem remains linear. The problem is solved by iterations, influential matrixes of residual displacements, and stresses are used. In next case, the equations of problem analysis and dependences are presented according to complete equation system of plasticity theory. Then the objective function of optimization problem becomes non-linear and it is solved in single stage. Solving the second problem, we check if it is possible to satisfy frame rigidity constrains, which are inferior or superior limits of residual displacement. This is considered as a linear programming problem. Mathematical model of frame load optimization problem at shakedown was made with the help of non-linear mathematical programming theory. Numerical experiment was realized with Rozen's gradients projecting method and using the penalty function techniques. Mathematical programming complementarity conditions prohibit taking into account the dechargable phenomena in some cross-sections, therefore analysis of residual deformation compatibility equations are performed, using linear mathematical programming.

Стилі APA, Harvard, Vancouver, ISO та ін.

Febriyanti, Eka, Dedi Priadi, and Rini Riastuti. "Pengaruh Peningkatan Derajat Deformasi Canai Hangat Terhadap Karakteristik Deformation Band Paduan Cu-Zn 70/30." Material Komponen dan Konstruksi 15, no. 2 (February 22, 2019): 9. http://dx.doi.org/10.29122/mkk.v15i2.3373.

Повний текст джерела

Анотація:

Abstract Cu-Zn 70/30 alloy has properties that is relatively soft, ductile, and easy to perform by cold working. However, cold working has the disadvantage that require equipment which has higher loading capacity to generate strength and higher density thus increasing of machining cost. In addition, strain hardening phenomenon due to cold working process resulted in decreasing of ductility material. Therefore, it is necessary alternative fabrication processes to optimize the mechanical properties of Cu-Zn alloy 70/30 that with the TMCP method. TMCP is metal forming material by providing large and controlled plastic strain to the material. TMCP using the deformation percentage variation that 32.25%, 35.48%, and 38.7% from hot rolled research at 500°C temperature in double pass reversible which performed on Cu-Zn 70/30 plate. By tensile testing using universal testing machine can be seen that the Cu-Zn 70/30 alloy on 32.25% degree of deformation, both of UTS and YS respectively are 505 MPa and 460 MPa. Whereas from examination of thickness and density deformation bands by FE-SEM shows denser and thicker deformation band proportional with increasing of deformation degree.Moreover, the values of tensile strength at the edge of the area and the center is directly proportional to the density and thickness of the deformation band. Paduan Cu-Zn 70/30 memiliki sifat yang relatif lunak, ulet, dan mudah dilakukan pengerjaan dingin. Namun, pengerjaan dingin memiliki kekurangan yaitu membutuhkan peralatan yang memiliki kapasitas pembebanan tinggi untuk menghasilkan kekuatan dan kepadatan tinggi sehingga meningkatkan biaya permesinan. Selain itu, fenomena pengerasan regang akibat proses pengerjaan dingin menghasilkan penurunan keuletan material. Oleh karena itu, diperlukan alternatif proses fabrikasi untuk mengoptimalkan sifat mekanik paduan Cu-Zn 70/30 salah satunya dengan metode TMCP. TMCP merupakan suatu proses perubahan bentuk suatu material dengan cara memberikan regangan plastis yang besar dan terkontrol terhadap material. TMCP dengan menggunakan variasi persentase deformasi sebanyak 32,25%, 35,48%, dan 38,70% dari penelitian canai hangat di suhu 500oC secara double pass reversible dilakukan pada pelat paduan Cu-Zn 70/30. Dengan melakukan pengujian tarik menggunakan mesin uji tarik universal testing machine dapat dilihat bahwa pada material paduan Cu-Zn 70/30 pada derajat deformasi 32,25% menghasilkan nilai UTS dan YS masing-masing sebesar 505 MPa dan 460 MPa. Sedangkan dari hasil pengamatan ketebalan dan kerapatan deformation band menggunakan FE-SEM menunjukkan deformation band yang lebih rapat dan lebih tebal sebanding dengan semakin meningkatnya derajat deformasi. Selain itu, nilai kekuatan tarik pada daerah tepi dan tengah berbanding lurus dengan kerapatan dan ketebalan deformation band. Keywords: 70/30 Cu-Zn alloy, warm rolled, deformation degree, deformation bands

Стилі APA, Harvard, Vancouver, ISO та ін.

Nakajima, Nobuyuki. "Time-dependent thermodynamics applied to flow of suspensions and polymer melts." Journal of Elastomers & Plastics 48, no. 8 (July 28, 2016): 754–60. http://dx.doi.org/10.1177/0095244315618701.

Повний текст джерела

Анотація:

Rheological behavior has been treated in terms of the energy flow by coupling it with deformation and flow of material. The method follows time-dependent thermodynamics, which is different from Prigogine’s irreversible thermodynamics. We have examined the rate of energy production with particular attention to the physical meaning of the sign of the rate. Just as the sign of energy indicates in thermodynamics, whether or not the reaction is spontaneous, the sign of the rate indicates in time-dependent thermodynamics, whether or not the reaction is stable. In the stable region, the reaction is reversible. For a change from stable region to an unstable region, there is a discontinuity. Then, there is a pseudo-stable region, where a partial reversibility may be observed. This behavior involves yielding, which leads to fracture, like that seen in a longtime creep failure of a solid material. We have examined non-Newtonian flow of polyvinyl chloride plastisol, steady-state flow of high-density polyethylene melts, and its stress growth toward steady state.

Стилі APA, Harvard, Vancouver, ISO та ін.

Baikovs, Andris, and Kārlis Rocēns. "PREDICTION OF THE ANTICLASTIC SHAPE CHANGES OF HYBRID COMPOSITE MATERIAL." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 16, no. 2 (June 30, 2010): 222–29. http://dx.doi.org/10.3846/jcem.2010.25.

Повний текст джерела

Анотація:

In search of structurally better and aesthetically more attractive solutions of the erection of various structures, non‐standard anticlastic elements are used more frequently. Therefore preservation of the initial shape of timber composite material sheets by using of reinforced plastic reinforcement has been investigated. Calculation model for determination of the thickness of rational reinforcement anticlastic sheet, which provides change of the original bending radius under variable moisture conditions (Baikovs and Rocens, 2006) within the limits of preferable intervals is developed by authors and using finite element method, calculations and modelling of sheet deformations are carried out with software package ANSYS v.11 (henceforth FEM) and by developed analytical method. Comparative research of the results calculated with the FEM and developed calculation model showed that the difference between results in the three cases investigated, when the composite timber material is reinforced on the top, bottom and both sides for the most of the cases does not exceed 3.3%. An opportunity to provide the original shape of anticlastic timber composite material sheets by using glass fibre reinforced plastic reinforcement under variable moisture conditions and not exceeding the difference of 5% has been demonstrated. Santrauka Ieškant ivairiu konstrukciju statiniu konstrukciškai geresniu ir estetiškai patrauklesniu sprendiniu, dažniausiai naudojami nestandartiniai antiklastiniai elementai. Todel buvo tyrinetas medienos kompozitines medžiagos lakštu pradinio pavidalo išsaugojimas naudojant sustiprinta plastiko armatūra. Skaičiuojamasis modelis, padedantis nustatyti racionaliai armuoto antiklastinio lakšto stori, kuris pakeičia pradini lenkimo spinduli kintamomis dregmes salygomis (Baikovs, Rocens 2006) tarp priimtinu intervalu ribu, yra sukurtas autoriu ir, taikant baigtiniu elementu metoda, lakšto deformaciju skaičiavimai bei modeliavimas atlikti kompiuteriniu programu paketu ANSYS v. 11 (toliau ‐ FEM) ir pagal sukurta analitini metoda. Rezultatu, apskaičiuotu su FEM ir pagal sukurta analitini modeli, lyginamasis tyrimas parode, kad skirtumas tarp triju tirtu atveju, kai medienos kompozitine medžiaga yra armuota viršuje, apačioje ir iš abieju pusiu, rezultatai daugeliu atveju neviršija 3,3%. Parodyta galimybe suteikti originalu pavidala antiklastiniams medienos kompozitiniams lakštams naudojant stiklo pluoštu sustiprinto plastiko armatūra ivairiomis dregmes salygomis ir neviršijant 5% skirtumo.

Стилі APA, Harvard, Vancouver, ISO та ін.

Fiorito, Marco, Daniel Fovargue, Adela Capilnasiu, Myrianthi Hadjicharalambous, David Nordsletten, Ralph Sinkus, and Jack Lee. "Impact of axisymmetric deformation on MR elastography of a nonlinear tissue-mimicking material and implications in peri-tumour stiffness quantification." PLOS ONE 16, no. 7 (July 9, 2021): e0253804. http://dx.doi.org/10.1371/journal.pone.0253804.

Повний текст джерела

Анотація:

Solid tumour growth is often associated with the accumulation of mechanical stresses acting on the surrounding host tissue. Due to tissue nonlinearity, the shear modulus of the peri-tumoural region inherits a signature from the tumour expansion which depends on multiple factors, including the soft tissue constitutive behaviour and its stress/strain state. Shear waves used in MR-elastography (MRE) sense the apparent change in shear modulus along their propagation direction, thereby probing the anisotropic stiffness field around the tumour. We developed an analytical framework for a heterogeneous shear modulus distribution using a thick-shelled sphere approximation of the tumour and soft tissue ensemble. A hyperelastic material (plastisol) was identified to validate the proposed theory in a phantom setting. A balloon-catheter connected to a pressure sensor was used to replicate the stress generated from tumour pressure and growth while MRE data were acquired. The shear modulus anisotropy retrieved from the reconstructed elastography data confirmed the analytically predicted patterns at various levels of inflation. An alternative measure, combining the generated deformation and the local wave direction and independent of the reconstruction strategy, was also proposed to correlate the analytical findings with the stretch probed by the waves. Overall, this work demonstrates that MRE in combination with non-linear mechanics, is able to identify the apparent shear modulus variation arising from the strain generated by a growth within tissue, such as an idealised model of tumour. Investigation in real tissue represents the next step to further investigate the implications of endogenous forces in tissue characterisation through MRE.

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Дисертації з теми "Plastiska deformationer"

Pettersson, Torbjörn. "OMBYGGNAD AV TRAFIKPLATS : Ekhagsmotet i Jönköping." Thesis, Jönköping University, JTH, Civil Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-10491.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Marko, Vilotić. "Intenzivna plastična deformacija u procesima višefaznog sabijanja materijala." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2015. http://www.cris.uns.ac.rs/record.jsf?recordId=95538&source=NDLTD&language=en.

Повний текст джерела

Анотація:

Predstavljena je nova metoda intenzivne plastične deformacije – višefazno sabijanje V-alatom. Koristeći ovu metodu, sabijanjem u osamnaest faza, unapređene su mehaničke osobine niskougljeničnog čelika Č.1221 – tvrdoća, čvrstoća i deformabilnost. Za ispitivanje mikrostrukture korišćeni su svetlosni, skening i transmisioni mikroskop. Prosečna veličina kristalnog zrna početnog materijala od 19 mikrometara je smanjena na 250 nanometara nakon dvanaest faza sabijanja. Nakon osamnaest faza sabijanja na čelu uzorka ostvarena je ukupna deformacija u iznosu od 3,38.
A new severe plastic deformation method has been presented - multistage upsetting by V-shape dies. By using this method, in eighteen upsetting stages, mechanical propreties (hardness, strenght and formability) of C15E low carbon steel has been improved. For microstructure analysis light, scanning and transmission microscopes have been employed. Initial average grain size of 19 μm has been reduced to 250 nm after twelve upsetting stages. After eighteen upsetting stages, total effective deformation at the sample forehead of 3,38 has been obtained.

Стилі APA, Harvard, Vancouver, ISO та ін.

Langschwager, Kay [Verfasser], Matthias [Akademischer Betreuer] Oechsner, and Michael [Akademischer Betreuer] Vormwald. "Lokales Deformations- und Schädigungsverhalten zyklisch elastisch-plastisch beanspruchter Schweißverbindungen / Kay Langschwager ; Matthias Oechsner, Michael Vormwald." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2020. http://d-nb.info/1211088588/34.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Aastorp, Knut Iver. "Plastic Deformation at Moderate Temperatures of 6XXX-series Aluminium Alloys." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-118.

Повний текст джерела

Анотація:

The present work has been carried out in order to investigate Al-Mg-Si alloys that are deformed at moderate temperatures. These temperatures are in the range between 200 C and 300 C. Also some experiments are performed at room temperatures. Two deformation models have been applied in the experiments: material deformation by compression testing and by forward extrusion.

The investigated alloys are AA6063, AA6082 and an alloy that is named “Alloy R” in this work. The latter alloy is the industrial alloy AA6082 without the Mn-addition (0.56wt%Mn in the AA6082). The “R” denotes the recrystallized microstructure in the material after hot forming operations.

The investigations show the effect of changing the temperature in the given temperature interval on the stress-strain relationship for each alloy. From the compression testing, it is found that none of the alloys AA6063 or Alloy “R” reaches a steady state condition as true strain approaches 0.8 for deformation temperatures between 200 C and 250 C. At compression testing performance at 300 C, the alloy “R” reaches a steady state condition at a true strain equal to 0.4.

As true stress-true strain relationship has been investigated for the “Alloy R” and the AA6063 at comparable deformation parameters, it is shown that the alloy “R”, with the highest Si-content, requires the highest true stress for a given true strain value (AA6063: 0.45wt%Si, Alloy “R”: 0.87wt%Si).

From the compression testing, the effect of Mn on the material properties in the AA6082-alloy has been determined. For the Alloy “R” and the AA6082, the true stress reached the same value after a certain amount of deformation. As deformation temperature increases, this common value of true stress corresponds to a decrease in true strain.

The AA6082 and Alloy “R” are also compared in experiments performed in forward extrusion. One observes that for the same deformation temperature and at identical die diameters, the ram force is identical. It is worth noticing that these alloys did not show the same relationship during the compression testing at low values of true strain (<0.8). On a microscopic scale, one concludes that Mn has no significant effect on the stress-strain relationship for the applied deformation parameters in the forward extrusion equipment.

Hardness measurements indicate that the age hardening potential in the extruded test specimen decreases as the deformation temperature increases. The hardness data is similar for both the AA6082 and the Alloy R, thus indicating that the Mn content has no significant effect on the strength of the material.

The deformed material has been annealed in order to investigate the recrystallization process in the AA6082 and the Alloy “R”. The recrystallization grain size in the Alloy “R” is significantly larger than in the AA6082 at comparable deformation parameters after annealing at 530 C for 15 minutes. This result is due to the effect of Mn-containing dispersoids in the AA6082. The recrystallization grain size in the Alloy “R” seems to be unaffected by the deformation temperature after annealing for 15 minutes. The observation of the AA6082 is quite different. A small increase in grain size is observed for both reduction ratios as the deformation temperature is elevated from 20C to 200 C and further to 250 C. At extrusion temperatures of 300 C the recrystallization grains are significantly larger.

Annealing experiments performed at 430 C on the AA6082 indicates that a change in the deformation temperature from 200 C to 250 C does not affect the amount of stored energy in the material significantly.

The Forge2 programme has been used to perform numeric simulations of the forward extrusion experiment. From this the temperature distribution, strain rate variation and true strain development in the test piece had been investigated. As the simulated true strain values are compared to the grain size in the annealed material, the recrystallization grain size is related to the amount of stored energy in the material in a very convincing way. It is also shown that the recrystallization grain diameter is related to the amount stored energy as the grain diameter is investigated in the radial and the extrusion direction separately.

Стилі APA, Harvard, Vancouver, ISO та ін.

Motylenko, Mykhaylo. "Beitrag zur Analyse von Disklinationsstrukturen in plastisch verformten Metallen." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2011. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-67416.

Повний текст джерела

Анотація:

Gegenstand der Arbeit ist die Analyse der bei hohen Verformungsgraden in Werkstoffen durch kollektive Bewegung der Versetzungen entstandenen neuen Defektkonfigurationen, die auf der mesoskopischen Skala agieren. Diese so genannte Disklinationen rufen neben starken Gitterdehnungen auch erhebliche lokale Gitterrotationen hervor. Es wurde der Nachweis der Existenz der Disklinationen in plastisch verformten Kristallen geliefert sowie die qualitative und quantitative Analyse der Disklinationskonfigurationen und der Disklinationsstärke durchgeführt. Die Untersuchungen an stark verformten Ein- und Vielkristallen wurden mittels sowohl lokalen Methoden der Transmissions- (TEM, CBED) und Rasterelektronenmikroskopie (REM, EBSD) als auch der integralen Methoden der Röntgenstrukturanalyse (XRD) durchgeführt. Die Ergebnisse haben gezeigt, dass die Entwicklung der Zellblockstruktur mit erheblichem Anstieg der Desorientierungen und Versetzungsdichten in Versetzungswänden verbunden ist und durch die Bildung der Netzwerke von Disklinationen gefördert wird.

Стилі APA, Harvard, Vancouver, ISO та ін.

Leiss, Bernd. "Strukturbezogene Textur- und Korngefügeuntersuchungen plastisch deformierter Dolomitgesteine am Südwestrand des Damara Orogens (Namibia) : Mechanismen der Texturbildung und ihre kinematische Bedeutung; mit 7 Tab. /." Stuttgart : Schweizerbart, 1996. http://www.gbv.de/dms/goettingen/191563315.pdf.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Štěpánek, Roman. "Teplotní stabilita Mg-slitiny AZ91 připravené pomocí intenzivní plastické deformace." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230220.

Повний текст джерела

Анотація:

This thesis dealt with thermal stability of magnesium alloy AZ91 prepared by severe plastic deformation, which leeds to fine grained structure. This structure is characterised by its inherent instability and this thesis tries to find out the value of critical temperature and rate of this instability, which manifests as grain coarsening.

Стилі APA, Harvard, Vancouver, ISO та ін.

Mohammadi, Ramona. "Verifieringsmetod för flexibla avgasledande element - Felmodsanalys." Thesis, KTH, Maskinkonstruktion (Inst.), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192488.

Повний текст джерела

Анотація:

Detta examensarbete utfördes på Scania CV AB och behandlar delar i lastbilens avgassystem som utsätts för korrosion och nötning. Huvudmålet med detta arbete är att utveckla en provmetod för livslängdsundersökning av flexibla slangar. En serie tester utfördes för att förstå grundorsakerna till brott och en FE-analys utfördes för att verifiera resultaten till dessa prov. En stor del av den flexibla slangen blir stel på grund av höga avgastemperaturer och som leder till plastisk deformation av slangen. Men de tre första lindningarna som ligger närmast motorn behåller sin flexibilitet på grund av kontinuerliga motorvibrationer. Slutsatsen är att huvudorsaken som gör att de flexibla slangarna går av, är slitage som leder till sprickinitiering. Den sprickan sprider sig i form av lågcykelutmattning d.v.s att det tar ganska kort tid tills brott sker i den flexibla slangen. Korrosion initierar mellan de icke-flexibla delar av slangen Korrosionshastigheten ökar med tiden och det orsakar små hål på ytorna. Baserat på testresultaten är den mest lämpliga stället för livslängdsundersökningar Scanias komponentprovceller. Genom att mäta slitagedjupet under repeterbara förhållanden som rekommenderas i rapporten och med hjälp av data från kundutfall, kan en livslängd uppskattas. För att kunna förbättra livslängden för de flexibla slangarna, rekommenderas att använda rostfritt stål typ 1.4828 vid tillverkning av dessa slangar bör varmformning användas, samt att avståndet mellan lagrena respektive tjockleken ökas. Flera tester med olika teststidsintervall behöver göras för att ta reda på nötningshastigheten.
This thesis was conducted at Scania CV AB with information based on corrosion and wear. The main goal of this work is to develop a test method to investigate the stripwounded hose’s lifetime. A series of tests were performed to understand the reasons of their failure and a FE analysis was performed to verify the results obtained from these tests. It was observed that a large part of stripwounded hose becomes stiff due to high temperatures of the exhaust gas. The high temperature leads to plastic deformation of the hose. In contrast, the three first windings closest to the engine keep their flexibility due to continuously engine vibrations while there is sign of wear between the layers in these three windings more than other parts of the stripwounded hose. Hence, it is concluded that the main reason for stripwounded hose’s unpredictable failures is wear which leads to crack initiation. The crack propagation is in type of low cycle fatigue which means that it takes a short time until the stripewounded hose breaks. Corrosion is initiated between the non-flexible parts of the hose. The rate of corrosion is increased by time and causes small holes on the surfaces. According to results from the experiments the most suitable location for the lifetime investigation is Scania’s component test cells . Several tests with different time spans needs to be performed. By measuring the wear depth rate under repeatable test conditions and bycomparing with stripwounded hoses from customer trucks, a lifetime can be estimated. To improve the fatigue lifetime of the stripwounded hoses, it is recommended to use stainless steel of type 1.4828, manufactured through hot-forming with larger distance between layers and thicker layers to find out the wear rate.

Стилі APA, Harvard, Vancouver, ISO та ін.

Kubiš, Milan. "Optimalizace sběrného výfukového potrubí Škoda 1,2 MPI." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-230446.

Повний текст джерела

Анотація:

The subject of this diploma thesis is optimalization of exhaust manifold of ŠKODA 1,2 MPI engine with respect for the plastic deformation at heat stress. The first part is focused on general description of converter module, whose component the exhaust manifold is. In the next part of the thesis is computation of a heat load of the exhaust manifold. The last part is devoted to the seal analysis of the whole converter module of a ŠKODA three-cylinder engine.

Стилі APA, Harvard, Vancouver, ISO та ін.

Valeš, Jan. "Počítačová simulace kolapsu budovy zplastizováním kloubů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225731.

Повний текст джерела

Анотація:

The aim of the thesis is to create an analytical 2D model of a multi-storey building and its consequent loading until the point of collapse which occures due to formation of plastic hinges. The first part is going to present a linear analysis of the problem; it focuses on location and level of load when the plastic hinges are formed. Then a nonlinaer analysis is going to be performed by RFEM programme using postcritical analysis and dynamic relaxation. Differences between the results of mentioned types and methods of analysis are going to be compared and an impact of variables is going to be evaluated .

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!