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Journal articles on the topic 'The cutting of flat shapes'
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1
Dadashpour, Ahmad, Asil Hassanpour, Reza Hojjat-Ansari, Behrooz Alinaghipour, and Yousef Hamidoghli. "Study about yield and cutting’s losses of two tea clone bushes in Iran." Genetika 47, no. 1 (2015): 289–94. http://dx.doi.org/10.2298/gensr1501289d.
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In the first trial, study conducted to compare of yield between two shapes of pruning (curved and flat) of tea bushes (clone 100). After leaf harvesting, curved pruning bushes had more yield than flat pruning bushes. Thus curved pruning method can be advised to gardeners as a reliable and superior pruning method. In the secondary experiment, study was carried out to investigation of cutting?s losses in all head-cuttings and comparison between tow types bush in tea (100 and selective). Results showed that there is significant difference between 100 and selective clones at p?0.05. It means that obtained mean cutting?s losses by selective was less than 100 bushes.
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Przepiórka, Jacek. "FRICTION FORCE OF THE NATURAL LEATHER CUTTING PROCESS." Tribologia 288, no. 6 (December 31, 2019): 81–85. http://dx.doi.org/10.5604/01.3001.0013.7772.
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Cutting natural leather is a first stage of a technological process of leather goods. It consists of dividing flat materials into shoe components. Cutting can be done by hand or mechanically. Cutters are the main cutting device in mechanical process. During utilization of cutters, the durability of its usage is an important issue. To increase its endurance, optimal force conditions are required. These depend on the following: the friction coefficient between cutting machine and cut material, the angle of sharpening of cutter, the blunting of the edge, using a cutting pad, and the type and kind of steel of which is produced. Friction is a component of a cutting force and its value depends on several factors, one of which is shape of the cutter. It is a parameter often ignored in the literature; however, according to the studies conducted by the authors, the value of the friction during cutting depends on the shape of the cutter. In this study, results of force value measurements required to cut elements of different shapes with equal circumferences with steel cutters are presented.
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Kano, Seisuke, and Atsushi Korenaga. "Mechanical Behavior of Single Crystal Copper for Different Shearing Directions." Advanced Materials Research 565 (September 2012): 490–95. http://dx.doi.org/10.4028/www.scientific.net/amr.565.490.
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The mechanical behavior of the surface of metals is strongly affected by surface fracture occurring in the process of mechanical shearing, especially in shaper-type cutting performed for the application of ultra-fine optical manufacturing and several types of nanotechnology. This discussion aims to elucidate the tribological behavior of pure Cu. In ultra-precise cutting, the physics of crystallographic interfaces is extremely important for controlling surface fracture behavior. In this study, surface fracture behavior was evaluated using single crystal copper cut in two different directions (along the (100) and (111) planes). For V-shaped groove cutting, the flat copper surface was cut with a diamond-tip cutting tool (with a V angle of 90°, a rake angle of 0°, and an escape angle of 7°) at a machining speed of 4-4000 mm/min and a cutting depth of 0.2-10 m. The machined surface was observed with a laser scanning microscope and compared with two groove shapes, in which the cutting grooves in the two cutting directions were found to be different. This result was considered to depend on whether the cutting tool moved along the slip planes {111}, which are oriented in the direction. In the case of shallow cutting (under 1 m), the springback behavior became apparent for cutting in the slip plane direction, where the mechanism of this behavior would be associated with the interface between slip-plane fractures created by the cutting tool.
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Peldschus, Friedel, and Jens-Thorsten Wild. "EXPERIMENTAL INVESTIGATIONS IN CHISELLING SOLID CONCRETE." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 9, no. 1 (March 31, 2003): 68–75. http://dx.doi.org/10.3846/13923730.2003.10531303.
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Experimental research was performed for analysing the chiselling process. The conditions of crack formation and crack propagation have been analysed. In the first step impact tests with a standard chisel shapes and with a pointed chisel were performed. These tests represented the basic investigations into the chisel load effects on mechanical processing of concrete. In the next step precise modifications were applied to the flat-chisel cutting edge with the aim of improving the cutting-edge geometry.
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Djuricic, Zoran, and Miodrag Manic. "Intelligent nesting system." Yugoslav Journal of Operations Research 13, no. 2 (2003): 229–43. http://dx.doi.org/10.2298/yjor0302229d.
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The economy of the process for the manufacture of parts from sheet metal plates depends on successful solution of the process of cutting various parts from sheet metal plates. Essentially, the problem is to arrange contours within a defined space so that they take up minimal surface. When taken in this way, the considered problem assumes a more general nature; it refers to the utilization of a flat surface, and it can represent a general principle of arranging 2D contours on a certain surface. The paper presents a conceptual solution and a prototypal intelligent nesting system for optimal cutting. The problem of nesting can generally be divided into two intellectual phases: recognition and classification of shapes, and arrangement of recognized shapes on a given surface. In solving these problems, methods of artificial intelligence are applied. In the paper, trained neural network is used for recognition of shapes; on the basis of raster record of a part's drawing, it recognizes the part's shape and which class it belongs to. By means of the expert system, based on rules defined on the basis of acquisition of knowledge from manufacturing sections, as well as on the basis of certain mathematical algorithms, parts are arranged on the arrangement surface. Both systems can also work independently, having been built on the modular principle. The system uses various product models as elements of integration for the entire system. .
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Yuliawan, Wendi. "Pertumbuhan Beberapa Bentuk Potongan Pangkal Setek Tanaman Mawar (Rosa sp.) Akibat Cara Aplikasi Zat Pengatur Tumbuh Root-Up." Paspalum: Jurnal Ilmiah Pertanian 7, no. 1 (June 1, 2019): 42. http://dx.doi.org/10.35138/paspalum.v7i1.111.
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The research aims to study the growth of rose cuttings due to the shape of the base of cuttings and the way of Root-up application. The experiment was carried out in Screen House in Pasirbanteng, Hegarmanah Village, Jatinangor District. Sumedang Regency. The experiment was conducted from March to August 2015. The methode based on Randomized Block Design consisting of two factors. The first factor is the Root-up (W) application method which consists of 3 factor levels, namely without root up (w1), powder (w2), and paste (w3). The second factor is Form Cutting (S) consisting of 3 levels of treatment, is the oblique sliced (s1), taper sliced (s2), and flat sliced (s3). The factors composed of nine combinations of treatments, each of which was repeated 3 times. The results show that was not the interaction between the shape of cuttings and Root-up applications on the growth response variables of cutting rose plants, is number of shoots, length of shoots, root length, number of roots, and root volume. The oblique sliced and tapered slice form the base and of the cutting shave the best effect on the length of shoots of rose plants cutting
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Castle, Toen, Daniel M. Sussman, Michael Tanis, and Randall D. Kamien. "Additive lattice kirigami." Science Advances 2, no. 9 (September 2016): e1601258. http://dx.doi.org/10.1126/sciadv.1601258.
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Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes.
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Eron’ko, S. P., E. V. Oshovskaya, and O. A. Kovaleva. "Study of strain-stress state of flat knives for cutting thin-walled pipes." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 77, no. 9 (September 21, 2021): 1039–46. http://dx.doi.org/10.32339/0135-5910-2021-9-1039-1046.
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Cutting of pipes into measured lengths on-line of pipe welding mill by disc saws and by facilities of abrasive cutting requires special measures of safety of personal. Besides, the necessity of frequent change of cutting instrument results in losses of production time. To eliminate the drawbacks, a study was initiated related to creation of shears which could enable to accomplish a quality transverse cutting of thin-walled pipes of small diameter by flat knives with various form of the working edges. A methodology and the results of study of strain-stress state of flat knives with application of physical and mathematical simulation of the process of transverse cutting of thin-walled pipes of small diameter presented. At the physical simulation using a polarization-optical installation, the pictures of deformation centers arising in the lower part of the knife in the zone of contact of its cutting edges with the body of the hollow circular profile being cut by it were obtained. In the experiment, models of three types of knives made of organic glass on a scale of 1:1 were used. Cutting edges of the knives for cutting pipes of 25 mm outer diameter, wall thickness of 2 mm were wedge-shaped, convex semicircular and concave. The data from studies of the loaded state of transparent knife models served as the basis for mathematical simulation of the strain-stress state of the shears cutting tool in the SolidWork application package using a strength analysis module that implements the finite element method in the form of tetrahedrons. The current values of the pipe cutting force used in the mathematical model were preliminarily calculated according to the previously proposed dependence, taking into account the strength of the hollow profile material and the area of the cut layer of its cross section for a given relative displacement of the cutting edges of the knife. The results of mathematical modeling were the pictures of deformations and equivalent stresses of the cutting part of the knife, determined according to the third theory of strength. A qualitative similarity has been established for the distribution patterns of stress fields recorded using the polarization-optical method on knife models and obtained in mathematical modeling for working samples of the shears cutting tool operated under the conditions of pipe welding mills. The proposed mathematical model makes it possible to estimate the values of the maximum equivalent stresses in the working part of a flat knife, taking into account the shape of its cutting edges, as well as the force required for cutting a thin-walled pipe into measured lengths with the corresponding dimensions of its cross-section and the strength of the material.
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Wheeler, R. L., and A. N. Key. "Hovercraft Skirt Design and Manufacture." Proceedings of the Institution of Mechanical Engineers, Part B: Management and engineering manufacture 201, no. 2 (May 1987): 79–84. http://dx.doi.org/10.1243/pime_proc_1987_201_049_02.
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Skirts are the inflated structure which extend around and beneath a hovercraft that allow the craft to operate in rough seas and over uneven ground. The early skirts were designed on the basis of model testing and practical experience, but as the size of craft increased and improved performance was required it became evident that a more sophisticated approach was needed. This was carried out by developing computer programs to design the sectional shapes, investigate the quasi-static behaviour and derive the flat pat tern shapes from which the skirt is made. The responsive skirts fitted to large cross-Channel hovercraft, the Super 4, and the latest coastal craft, the AP 1-88/100 were developed using these techniques. Investigations into the cutting of sheets of non-metallic materials by a high-pressure water jet showed that this was ideal for the nylon woven fabric coated with either natural rubber or neoprene from which skirts are made. A cutting table with a NC tape-fed controller has been developed with a jet of 0.15 mm (0.006 in) diameter operating at 379 MPa (55000 lbf/in2). All the processes of producing a skirt, design, detailing with CADAM, part programming and cutting out are now integrated via computer links giving significant savings of time and costs.
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Aoyama, Hideki, Yumiko Suzuki, and Noriaki Sano. "Determination Method of Locations and Postures of Cutting Tool for 5-Axis Machining Based on Intuition and Minimum Cusp Height." Key Engineering Materials 516 (June 2012): 96–101. http://dx.doi.org/10.4028/www.scientific.net/kem.516.96.
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Currently used CAM systems for 5-axis machining can determine tool paths with collision-free tool postures. However, the algorithm implemented in the CAM systems sometimes generates un-optimum tool paths and postures from the viewpoint of machining processes and machine tool operation. This study proposes two methods to determine tool paths and tool postures for 5-axis machining based on the viewpoints of human intuition and minimum cusp height for resolving the problems. A method is developed for inputting the positions and postures of a cutting tool when executing virtual machining. In the execution of virtual machining, a virtual cutting tool can be intuitively moved by a haptic device to determine the desired locations and postures of the cutting tool. By using the system, the tool locations and tool postures to machine complicated shapes with overhang can be easily determined based on the operators intuition. Another method is for determining tool postures for making minimum cusp height by matching the cutting edge of a flat end-mill to the cross-section shape at a point on surfaces to be machined. A basic system to determine the tool postures based on making minimum cusp height was developed. The cusp height on the surfaces generated by the basic system was smaller than the height generated by 3-axis ball-end milling.
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Slabkyі, Andrіі, Olexandr Manzhilevskyy, and Olexandr Polishchuk. "Analysis of structures of flat planting machines." Journal of Mechanical Engineering and Transport 13, no. 1 (2021): 140–48. http://dx.doi.org/10.31649/2413-4503-2021-13-1-140-148.
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One of the methods of material processing is considered, which allows to obtain high geometric accuracy and low surface roughness of parts, namely their abrasive finishing. The high quality of machining of parts in this way is due to the use of coordinated relative movement of the workpiece and the cutting tool. According to the kinematic features, most lapping machines can be divided into two groups: machines with oscillating working motion and machines with rotating lapping motion. The machines of the first group are more common due to the simplicity of their design and versatility. However, the possibility of their use is limited by the size range of the workpieces and uneven wear of the cutting tool and, as a consequence, the uneven surface treatment of the part. The machines of the second group are considered the most versatile, as they allow processing a wide range of parts, varying in shape and size, but they are also not without such a disadvantage as uneven wear of the cutting tool with all the corresponding consequences. Improving the efficiency of abrasive finishing by complicating the trajectory of the relative movement of the tool and the part, ie the formation of a unique mutual working movement of the lapping and the movement of the workpiece, is one of the most common areas. The main disadvantage of equipment that provides processing of parts on this principle is, in most cases, limited regulation of the operating parameters of the cutting process, so this area remains promising and has broad prospects for development. The constructive scheme of the hydraulic-pulse flat-lapping machine offered in work thanks to a combination of advantages of the hydraulic-pulse drive with use of numerical program control will allow to provide unique mutual multi-movement of preparation and the lapping tool with a possibility of adjustment of its parameters in the course of processing. Purposeful choice of the shape and density of the trajectory of the working movement of the tool will form a micro relief of the treated surface with the necessary statistical parameters and low roughness.
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Kang, D. B., S. M. Son, and J. H. Ahn. "Real-Time Geometric Error Compensation in Micro Grooving the Workpiece with Large Surface Area." Key Engineering Materials 339 (May 2007): 314–20. http://dx.doi.org/10.4028/www.scientific.net/kem.339.314.
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A workpiece with a large surface area is likely to be uneven due to form error and waviness. These geometric disturbances can cause inaccurate micro shapes to be formed when micro features are micro-grooved into the surface and cause the resulting workpiece to fail to function as desired. Thus, the real-time monitoring and compensation is required to guarantee the form accuracy of micro features while machining the workpiece with a large surface area. In this study, a method is suggested for real-time measurement and compensation of geometric errors for the micro grooving of a large flat surface using a laser displacement sensor placed ahead of the cutting tool. Experimental results show that the compensated surface profiles fit the measured ones within an allowable tolerance even at cutting speeds as high as 200 mm/s.
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Kim, Eun, and Choon Lee. "A Study on the Machining Characteristics of Curved Workpiece Using Laser-Assisted Milling with Different Tool Paths in Inconel 718." Metals 8, no. 11 (November 20, 2018): 968. http://dx.doi.org/10.3390/met8110968.
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Difficult-to-cut materials are being increasingly used in many industries because of their superior properties, including high corrosion resistance, heat resistance and specific strength. However, these same properties make the materials difficult to machine using conventional machining techniques. Laser-assisted milling (LAM) is one of the effective method for machining difficult-to-cut materials. In laser-assisted milling, the machining occur after the workpiece is locally preheated using a laser heat source. Laser-assisted milling has been studied by many researchers on flat workpiece or micro end-milling. However, there is no research on the curved shape using laser assisted milling. This study investigated the use of laser-assisted milling to machine a three-dimensional curved shape workpiece based on NURBS (Non-uniform rational b-spline). A machining experiment was performed on Inconel 718 using different tool paths (ramping, contouring) under various machining conditions. Finite elements analysis was conducted to determine the depth of cut. Cutting force, specific cutting energy and surface roughness characteristics were measured, analyzed and compared for conventional and LAM machining. LAM significantly improved these machining characteristics, compared to conventional machining. There results can be applied to the laser-assisted milling of various three-dimensional shapes.
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Wan, Min, Wen Jie Pan, and Wei Hong Zhang. "Identification of Cutting Shear Stress, Shear and Friction Angles Using Flat End Milling Tests." Materials Science Forum 836-837 (January 2016): 112–16. http://dx.doi.org/10.4028/www.scientific.net/msf.836-837.112.
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Orthogonal-to-oblique transformation model, which is formulated based on the cutting database including shear stress, shear and friction angles, can be used to predict cutting forces in high speed milling process and any other machining process. The involved shear stress, shear and friction angles are traditionally identified from abundant number of turning experiments. For the purpose of saving experimental cost, this paper presents a novel method to identify these parameters directly from flat end milling processes. Identification procedures are established by transforming the cutting forces measured in Cartesian coordinate system into a local system. The advantage lies in that in spite of the cutter geometries and cutting conditions, only a few tests are required to develop the model, which is experimentally validated to be effective for predicting the cutting force in terms of magnitude and shape in other machining cases.
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Li, Hui Ying, and Liang Ji Chen. "CC Path Generation Method Based on Cutting Shape of Flat-End Cutter." Applied Mechanics and Materials 621 (August 2014): 157–61. http://dx.doi.org/10.4028/www.scientific.net/amm.621.157.
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The calculating algorithm for Cutter Contacting (CC) paths is proposed in this article to enhance machining precision of complex surfaces with a flat-end cutter. With the style of coordinate transformation, effective cutting shape and equavellent machining radius of a flat-end cutter had been calculated and deduced, and the step-over distance formed by two adjacent CC paths were also obtained. The corresponding NURBS path of tool center points including knot vector and controlling points was obtained from the cutter contacting points.The parameter increment along the CC path interval direction was calculated by using geometric analysis of the local area of CC point.
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Sadasiva, Rao T., K. Satyanarayana, Y. Praneeth, and Anne Venu Gopal. "Studies on the Effect of Approach Angle and Process Parameters in Face Milling." Applied Mechanics and Materials 110-116 (October 2011): 3147–55. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.3147.
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Milling is the most widely applied machining process for producing flat surfaces and prismatic shapes. To minimize the process time and maximize the quality of the workpiece, it is essential to monitor the condition of cutting tool in machining operation and to optimize the process parameters. In the present investigations, experiments were performed on EN31 steel with un-coated carbide inserts in face milling with tools having different approach angles in order to determine the performance of the tool. The effects of process parameters namely speed, depth of cut and feed on tool wear of work piece were investigated. The cutting forces and tool wear are measured in order to evaluate the performance of the cutter. Acoustic emission signal was used for the online tool monitoring. A statistical technique, Taguchi design of experiments was used to optimize the machining process parameters such as speed, feed, depth of cut and approach angle.
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Takeuchi, Y., M. Murota, T. Kawai, and K. Sawada. "Creation of Flat-End V-Shaped Microgrooves by Non-Rotational Cutting Tools." CIRP Annals 52, no. 1 (2003): 41–44. http://dx.doi.org/10.1016/s0007-8506(07)60526-5.
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Evans, Alexandra M., Jonah N. Choiniere, and Graham J. Alexander. "The cutting-edge morphology of the mole snake’s dental apparatus." PeerJ 7 (June 7, 2019): e6943. http://dx.doi.org/10.7717/peerj.6943.
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The mole snake (Pseudaspis cana) is capable of inflicting unusual bites in defence and during male combat that present as two parallel lacerations. We investigated the dental morphology of the mole snake by making SEM images, and by CT-scanning and digitally reconstructing the skulls of 14 specimens comprising both sexes. The lengths, volumes, shapes and positions of maxillary and dentary teeth were compared within individuals, between individuals, and between sexes. CT reconstructions show the occurrence of large, flat triangular teeth at the posterior end of the maxilla that are angled to point towards the posterior of the skull. SEM imagery highlights the presence of sharp ridges (carinae) on the posterior edges of the posterior dentary and maxillary teeth. Males have greater dental specialization, maxillary tooth variation, enlargement of the posterior-most maxillary teeth, and dentary teeth with posterior carinae. We hypothesize that mole snake dental specializations are adaptations for their particular form of male combat and possibly for subduing prey in the confines of underground burrows. Our findings reveal a complex dental morphology in mole snakes and provide impetus for further studies on the functional morphology of snake teeth.
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Sarwar, Mohammed, and Julfikar Haider. "Development of Advanced Surface Engineering Technologies for the Benefit of Multipoint Cutting Tools." Advanced Materials Research 83-86 (December 2009): 1043–50. http://dx.doi.org/10.4028/www.scientific.net/amr.83-86.1043.
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The benefits of applying advanced coatings on both single point and multipoint cutting tools such as improvement of productivity, tool life, machined surface quality etc. have been realised by the surface engineering researchers [1], commercial coaters [2-4] and end users [5]. The demand for advanced coatings in cutting tool industries is continually growing to meet the challenges of high speed machining, dry machining, near net-shape machining, machining of hard-to-cut materials etc.. Advanced coatings with excellent properties on flat coupon in a laboratory deposited by modern deposition technologies should not be taken for granted in improving the performance of complex shaped cutting tools [6] in aggressive cutting environments. This is because the end performance of coated cutting tools is not only dependant on the coating itself but also on the tool substrate material, geometry, surface finish and cutting edge conditions prior to coating deposition. The paper presents case studies with examples of successes and failures of advanced coatings on different multipoint cutting tools (e.g., milling cutters, bandsaws, circular saws, holesaws etc.). The future strategy for developing successful coating technology for cutting tools should be directed towards adopting a systems approach to bridge the communication gap amongst the cutting tool manufactures, tool coaters and end users.
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Choirony, Iklil Vurqon, Mohammad Slamed Hariyanto, Miftachul Ulum, Achmad Ubaidillah, Haryanto Haryanto, and Riza Alfita. "Rancang Bangun Acrylic Engraver and Cutting Machine Menggunakan CNC Milling 3 Axis Berbasis Mikrokontroler." Elektrika 13, no. 1 (May 24, 2021): 13. http://dx.doi.org/10.26623/elektrika.v13i1.3071.
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<p><em><span lang="EN-US">The purpose of this research is to design and implement an automatic acrylic carving and cutting tool using a microcontroller-based 3-axis CNC machine. Computer Numerical Control (CNC) is a machine technology that is operated automatically to support the demand for a product that has a complex shape and high accuracy. In general, the construction of a 3-axis CNC machine and its working system is synchronization between the computer and its mechanics. This tool has a work process by utilizing the G-Code method as a command on the machine to carry out engraving and cutting automatically. The G-code was obtained from a previously designed image and then converted using the Aspire 9.0 software. Engraving and cutting is done by sending the G-code file to the microcontroller via the Universal G-code Sender software, then the microcontroller sends a signal to drive the motor driver which then drives the stepper motor so that the actuator movement is generated according to the image in the G-code file. Simultaneously the spindle motor will be active to engrave or cut acrylic. In this study, a trial scenario was carried out to determine the precision and accuracy of the tool, namely by engraving and cutting flat shapes such as squares, circles, triangles and segments. The percentage of success generated from this tool is 97,08% to 100%. Furthermore, testing is carried out to make products in the form of engraving writing, logos and calligraphy. Apart from that, we also tested cutting letters and key chains. When the test is carried out, the accuracy level is 1mm. </span></em></p>
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Alyas, Rasha Ramiz. "Investigation of CNC Milling Machining Parameters on Surface Roughness." Al-Khwarizmi Engineering Journal 14, no. 3 (September 4, 2018): 123–28. http://dx.doi.org/10.22153/https://doi.org/10.22153/kej.2018.01.008.
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Milling Machining is a widely accepted nontraditional machining technique used to produce parts with complex shapes and configurations. The material is removed in two stages roughing and finishing, the flat end cutter removed the unwanted part of material, then finished by end mill cutter. In milling technique, the role of machining factors such as cutting depth, spindle speed and feed has been studied using Taguchi technique to find its effectiveness on surface roughness. Practical procedure is done by Taguchi Standard matrix. CNC milling is the most conventional process which is used for removing of material from workpiece to perform the needed shapes. The results and relations indicate that the rate of feed is very important factor for modeling surface roughness. The plot of S/N ratio shows that the optimum combination of the milling factors that gives the best value of surface accuracy. The best combination of milling factors has also been predicted to minimize the surface roughness.
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Musa, Mateja Šnajdar, Matija Sakoman, Danko Ćorić, and Tamara Aleksandrov Fabijanić. "Exploitation and Wear Properties of Nanostructured WC-Co Tool Modified with Plasma-Assisted Chemical Vapor Deposition TiBN Coating." Metals 11, no. 2 (February 15, 2021): 333. http://dx.doi.org/10.3390/met11020333.
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In recent years, coated cemented carbides have often been the first choice for a wide variety of tool inserts and applications. Its success as a cutting tool material arises from the unique combination of wear resistance and toughness, and its ability to be formed into complex shapes. The structure obtained by sintering nanoparticle powders provides a significant improvement in product properties, such as higher cutting speeds, lower tool tolerances, and longer service life. In this study, a multi-layered gradient coating, deposited on nanostructured cemented carbides by plasma-assisted chemical vapor deposition (PACVD) was investigated with emphasis on its wear and exploitation properties. TiBN coating was deposited on nanostructured cemented carbide samples with the addition of 5 wt% Co, 10 wt% Co and 15 wt% Co. The samples were consolidated by one cycle hot isostatic pressing (HIP) technique. Complex architecture built of TiN and TiB2 gradient multilayer sequence block was deposited on each type of substrate. Wear resistance of the obtained samples was determined by erosion wear testing and dry sliding wear testing (ball-on-flat test). The friction coefficients of ~0.22 obtained for coated samples by the ball-on-flat test show a decrease in friction when compared to uncoated samples values of ~0.32. The absence of coating rupture was confirmed by wear track depth measurements showing a wear trace depth of ~1.2 μm. Exploitation properties i.e., tool life determination of samples was obtained using single-point turning tool test and compared to commercial cutting tool insert type K10 tested under the same conditions. All the conducted tests show excellent wear and exploitation properties of the newly developed TiBN coating under chosen conditions, including cutting speed, vc = 200 m/min, depth of cut, ap = 1 mm, and feed, fn = 0.2 mm. Coated WC-Co samples with 15 wt% Co, having withstood 15 min of machining with flank wear trace size less than 0.3 mm, suggest significant improvement when compared to trace size of 0.56 mm obtained for K10 commercial cutting insert.
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Frève, Andrew, and M. Auger. "TRANSPLANTATION OF POTATO SPROUT CUTTINGS ON WET PAPER TO IMPROVE AND INCREASE ROOTING AND SPEED UP MULTIPLICATION BY STEM CUTTING." HortScience 29, no. 4 (April 1994): 247e—247. http://dx.doi.org/10.21273/hortsci.29.4.247e.
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Rooting sprout cuttings (spc) is sometimes less successful than stem cuttings (stc). A rooting technique was developed between 1988 and 1991 at La Pocatière. The spc were taken after standing 72 hours in the dark followed by 1 day with 16 hours of light. The spc can be very small (2 mm): a node can be split in half if there are two axillary buds face to face. The spc were soaked in IBA and sandwiched between two paper towels. As many as 300 to 400 spc can be placed in a 28 × 53-cm flat. The papers were placed in flats between two transparent covers; the bottom cover contains water. The paper was moistened with water. The cuttings were maintained at 100% relative humidity for 7 days, then planted in soil in flats. After 5 days on paper, the unrooted cuttings were treated again with IBA on a larger surface and put back in the sandwich. There was less damping-off because the cut part was not placed immediately into the soil. One week after plantation, the plantlets' shape was better and more uniform than those planted directly into soil. The plants rooted on paper produce more stc/spc and more stc/stc than those rooted in soil.
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Guo, Pei Quan, Fen Liu, and Xiao Li Lai. "Cutting Force Prediction of Disc Cam Contour Milling." Materials Science Forum 800-801 (July 2014): 285–89. http://dx.doi.org/10.4028/www.scientific.net/msf.800-801.285.
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Cutting force equation was established for milling with flat end cutter as feeding in straight-line path by means of discretization method. The model of milling force was conducted based on the manufacturing character of cylindrical surface. The milling force is continual change in manufacturing process, it’s not only influenced by milling parameter, but also related with the shape of cam’s contour. Milling force can result in vibration as machining. Milling force prediction is very useful for manufacturing accuracy control.
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Kudryashov, E. A., I. S. Krylov, and N. A. Khizhnyak. "RATIONAL CONDITIONS OF COMPLEX SURFACES OF PARTS." Proceedings of the Southwest State University 22, no. 1 (February 28, 2018): 34–44. http://dx.doi.org/10.21869/2223-1560-2018-22-1-34-44.
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An important scientific and practical task is to increase the efficiency of designing technological processes for manufacturing parts of a complex form. The labour intensity of design work is connected with a wide variety of shapes and sizes of products created, the use of a wide range of structural materials and their combinations, presence on the machined surfaces of secondary holes of different sizes and locations, grooves, flats, recesses, and other elements that break the contour of the base surface of the workpiece and cause intermittence of the turning process. The purpose of this work is to use the complex part capabilities for the design of the group technology of machining. A complex part consisting of a complete set of all major and minor structural elements is an object artificially created for modeling the conditions of interrupted cutting of a sufficiently large group of similar complex parts of the Rotary body class. The condition of the part design causing intermittent cutting adversely affects the strength of the cutting element, due to possible brittle fracture in collision with the surface of the contour break of the base surface of the workpiece. To keep the operability of the active part of a cutting tool, a method is developed in which the initial meeting of the tip of the cutting element with the workpiece is replaced with a flat contact in the front surface area as far (distant) as possible from the brittle tip and cutting edges. Thus, the detection of elements of intermittences in the complex part and the conditions of shock-free turning of structurally complex surfaces of parts based on them allow us to determine the adjusted angles of the cutter by calculation and thereby minimize the negative factors of intermittent cutting that adversely affect the tool performance. The presence of objective information about rational conditions of shock-free turning allows us to make changes that improve the complex part machineability, unify the turning operation and use a specific technological process for any part of the group, excluding possible errors that could occur during usual design.
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Robertson, R. E., T. J. Chu, R. J. Gerard, J. H. Kim, M. Park, H. G. Kim, and R. C. Peterson. "Three-dimensional fiber reinforcement shapes obtainable from flat, bidirectional fabrics without wrinkling or cutting. Part 1. A single four-sided pyramid." Composites Part A: Applied Science and Manufacturing 31, no. 7 (July 2000): 703–15. http://dx.doi.org/10.1016/s1359-835x(00)00013-0.
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Li, Jiafang, and Zhiguang Liu. "Focused-ion-beam-based nano-kirigami: from art to photonics." Nanophotonics 7, no. 10 (September 19, 2018): 1637–50. http://dx.doi.org/10.1515/nanoph-2018-0117.
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AbstractKirigami, i.e. the cutting and folding of flat objects to create versatile shapes, is one of the most traditional Chinese arts that has been widely used in window decorations, gift cards, festivals, and various ceremonies, and has recently found intriguing applications in modern sciences and technologies. In this article, we review the newly developed focused-ion-beam-based nanoscale kirigami, named nano-kirigami, as a powerful three-dimensional (3D) nanofabrication technique. By utilizing the topography-guided stress equilibrium induced by ion-beam irradiation on a free-standing gold nanofilm, versatile 3D shape transformations such as upward buckling, downward bending, complex rotation, and twisting of nanostructures are precisely achieved. It is shown that the generated 3D nanostructures possess exceptional geometries and promising photonic functionalities, including strongly interacting multiple Fano resonances, giant optical chirality, clear photonic spin Hall effects, and diffractive phase/polarization effects. The studies of such structures can build up novel platforms for versatile manufacturing techniques and be helpful to establish new areas in plasmonics, nanophotonics, optomechanics, MEMS/NEMS, etc., with the generation of exotic but functional nanostructures.
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Shaheen, Wael, Sangarapillai Kanapathipillai, Philip Mathew, and B. Gangadhara Prusty. "Optimization of compound die piercing punches and double cutting process parameters using finite element analysis." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 234, no. 1-2 (June 10, 2019): 3–13. http://dx.doi.org/10.1177/0954405419855507.
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This article investigates different types of compound die piercing punches and double cutting operation parameters in terms of optimization using finite element technique, Taguchi method, regression analysis, and analysis of variance. The article overcomes the current knowledge gap in studying various cutting edges of piercing punches such as flat, chamfered, flat edge with concave hemisphere, and convex shaped when using the compound dies in stamping operations. The analysis of the compound die is carried out using ANSYS software. The main focus is to determine the contribution of key parameters for obtaining optimum cutting tool design. The best piercing punch is selected based on minimum burr height of the product. The values of cutting process parameters and burr heights have been analyzed using Minitab software. The results obtained indicate that the burr heights of the final product are at a minimum when the sheet metals are thicker and larger when the sheets are thinner. The chamfered and convex punches provided minimum burr heights which are as low as 0.034 mm for a typical sheet metal. This study provides a better outcome compared to the available experimental data in the literature. The investigation also designed efficient compound dies resulting in improved product quality.
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Yoshimaru, Masafumi, Yasuhiro Fujita, Tetsufumi Ito, Masahide Kouya, and Hiroshi Suzuki. "Development of Multi-Axis Cutting Method Using Non-Rotational Tool with Ultrasonic Vibration." International Journal of Automation Technology 2, no. 2 (March 5, 2008): 105–10. http://dx.doi.org/10.20965/ijat.2008.p0105.
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In recent years, rotary tools such as ball and flat end mills are widely used to produce dies and parts. Machining using rotary tools shortens cutting time, raising efficiency and discharging cutting chips cleanly, but leaves the machined face rough due to arc-shaped rotation marks. The radius of rotation for the location of the cutting edge from the tool's center axis is non-consistent, varying tool edge cutting speed and direction, making it difficult to leave surface roughness uniform. Removing unfinished areas and reducing final machined face surface roughness to the submicron level thus requires secondary finishing, which conventionally relies on hand polishing by a skilled worker. We developed extremely small cut-in machining using a non-rotational tool to establish final die machine finishing. We discuss machining tests with ultrasonic vibration added to machine prehardened steel, used mainly as a die material, to a mirror finish using a nonrotational diamond tool, and evaluate its usefulness.
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Lo Valvo, Ernesto, and Roberto Licari. "A More Efficient Method for Clustering Sheet Metal Shapes." Key Engineering Materials 344 (July 2007): 921–27. http://dx.doi.org/10.4028/www.scientific.net/kem.344.921.
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The nesting of two-dimensional irregular shapes is a common problem which is frequently encountered by a number of industries where raw material has to be, as economically as possible, cut from a given stock sheet. A frequently recurring problem as far as cutting stock is concerned, is how to obtain the best nesting of some pieces of flat patterns which occupy minimalarea convex enclosure. The area of convex enclosure is related to the convex hull of the union of patterns which can be imagined as a large rubber band surrounding the set of all polygons. Our goal is to automatically obtain the smallest area convex shape containing all the patterns. As a matter of fact, Cheng and Rao have proposed an heuristic “stringy effect” procedure for clustering which follows a descending order of area of patterns. The “stringy effect” is able to put each new piece in a position which minimises the value of the distance between the centroid of each added piece and the centroid of the already formed cluster. The procedures till now shown in literature are quite complex. They make use of sliding techniques, and are not able to effectively work with relatively multiply-connected figures. In particular, the different procedures proposed are based on the No Fit Polygon computation of non-convex polygons, which often generates holes. This work is a proposal for a more efficient method, which can be used in heuristic procedure. In this paper a new procedure for the calculation of “No Fit Polygon” (NFP) of non-convex polygons is presented. Given two non-convex polygons, the algorithm is able to calculate their NFP very quickly and without any approximation by a polygon clipping method. By iterating this procedure with every polygon of our set, and positioning them using the “stringy effect” technique, it is so possible to obtain a convex shape that contains all the patterns, having the minimal area.
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Serizawa, Hisashi, Yuji Sato, Naofumi Nakazato, Masahiro Tsukamoto, and Hirotatsu Kishimoto. "Effect of Slit Shape on Joinability of Zircaloy - SiC/SiC Composite Tube Joint with Titanium Powder." Materials Science Forum 941 (December 2018): 1944–49. http://dx.doi.org/10.4028/www.scientific.net/msf.941.1944.
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As for the fuel cladding in the light-water reactor, silicon carbide fiber reinforced silicon carbide matrix (SiC/SiC) composite is one of the promising candidates as a replacement of Zircaloy due to many superiorities, where it is necessary to develop the end-cap seal of SiC/SiC composite cladding. In this research, the caulking method was employed as the method for sealing the end cap of SiC/SiC composite tube by Zircaloy tube where the titanium micro-powder was inserted between two tubes. The fiber laser was circumferentially irradiated on the outer surface of zircaloy tube, and the insert method of titanium powder was varied by changing the cutting method of SiC/SiC composite tube. The examinations about the slit shape effect for the flat cutting suggested that the hook slit is considered to be the best cutting method for holding the titanium powder during the laser irradiation where the width of slit should be narrower than that of laser irradiation line.
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Fang, Ning. "Kinematic Characterization of Chip Lateral-Curl—The Third Pattern of Chip Curl in Machining." Journal of Manufacturing Science and Engineering 124, no. 3 (July 11, 2002): 667–75. http://dx.doi.org/10.1115/1.1468225.
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Two patterns of chip curl, namely up- and side-curl, have been widely recognized in machining operations. This paper presents the third pattern of chip curl that is called lateral-curl. The rotating axis of chip lateral-curl is perpendicular to the rotating axes of up- and side-curl. The essential differences are illustrated between the chip lateral-curl concept and the “chip-twisting” concept presented in other related studies. Based on an analytical vector analysis, a new kinematic characterization is presented for the natural (or born) lateral-curl of the chip that is associated with flat-faced tool machining. It is demonstrated that chip forms (or shapes) can be determined by four governing variables: the chip up-, lateral-, and side-curl radii and the chip side-flow angle. A method to indirectly measure the chip lateral-curl radius is presented. The effect of chip lateral-curl on chip forms is investigated through cutting tests, theoretical analysis, and computer simulations.
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Suzuki, Hirofumi, Mutsumi Okada, Koichi Okada, and Yosuke Ito. "Precision Cutting of Ceramics with Milling Tool of Single Crystalline Diamond." International Journal of Automation Technology 9, no. 1 (January 5, 2015): 26–32. http://dx.doi.org/10.20965/ijat.2015.p0026.
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Micro milling tools made of Single Crystalline Diamond (SCD) have been developed to machine micro dies and molds made of ceramics. The milling tools of a cylindrical SCD having many sharp cutting edges are fabricated 3-dimensionally by scanning a laser beam. Flat shape of binder-less tungsten carbide mold was cut with the developed milling tool to evaluate the tool wears and its life. Some micro aspheric molds of tungsten carbide were cut with the milling tool at a rotational speed of 50,000 min-1. The ceramic molds were cut in the ductile mode. By cutting with the milling tool, the form accuracy obtained was about 100 nm P–V and the surface roughness 8 nm Rz.
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Matsumoto, Y., D. Magda, D. W. Hoeppner, and Tae Young Kim. "Effect of Machining Processes on the Fatigue Strength of Hardened AISI 4340 Steel." Journal of Engineering for Industry 113, no. 2 (May 1, 1991): 154–59. http://dx.doi.org/10.1115/1.2899672.
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The effect of two finishing processes, namely, cutting and grinding, on the fatigue strength of hardened AISI 4340 steel was investigated. Three sets of flat tensile specimens were prepared by first machining into the general shape of the fatigue specimen standard, then they were hardened to HRC 54. The final grinding was carefully performed on one set of specimens. Two sets of specimens were fly cut to obtain a surface finish comparable to the ground surface. The residual stress distribution, surface structure, and surface profiles were determined. Fatigue testing was accomplished on these specimens in tension under load control. All the residual stress patterns were compressive, but the residual stress created by fly cutting reached a much deeper layer than that created by grinding. Fly cutting also produced a surface with a higher fatigue strength than the grinding did.
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Kushwaha, R. L. "FINITE ELEMENT MODELLING OF TILLAGE TOOL DESIGN." Transactions of the Canadian Society for Mechanical Engineering 17, no. 2 (June 1993): 257–69. http://dx.doi.org/10.1139/tcsme-1993-0016.
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A non-linear finite element model was developed for three dimensional soil cutting by tillage tools. A hyperbolic constitutive relation for soil was used in the model. Analysis was carried out to simulate soil cutting with rectangular flat and triangular tillage blades at different rake angles and with curved blades. Interface elements were used to model the adhesion and the friction between soil and blade surface. Soil forces obtained from the finite element model for the straight blades were verified with the results from laboratory tillage tests in the soil bin. The finite element model predicted draft force accurately for both tillage tools. Results indicated that the draft was a function of rake angle, tool shape and the curvature.
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Chen, Zhe, Jiawei Luo, Ivo Doudevski, Sema Erten, and Seong H. Kim. "Atomic Force Microscopy (AFM) Analysis of an Object Larger and Sharper than the AFM Tip." Microscopy and Microanalysis 25, no. 05 (July 16, 2019): 1106–11. http://dx.doi.org/10.1017/s1431927619014697.
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AbstractAtomic force microscopy (AFM) is typically used for analysis of relatively flat surfaces with topographic features smaller than the height of the AFM tip. On flat surfaces, it is relatively easy to find the object of interest and deconvolute imaging artifacts resulting from the finite size of the AFM tip. In contrast, AFM imaging of three-dimensional objects much larger than the AFM tip height is rarely attempted although it could provide topographic information that is not readily available from two-dimensional imaging, such as scanning electron microscopy. In this paper, we report AFM measurements of a vertically-mounted razor blade, which is taller and sharper than the AFM tip. In this case, the AFM height data, except for the data collected around the cutting edge of the blade, reflect the shape of the AFM tip. The height data around the apex area are effectively the convolution of the AFM tip and the blade cutting edge. Based on computer simulations mimicking an AFM tip scanning across a round sample, a simple algorithm is proposed to deconvolute the AFM height data of an object taller and sharper than the AFM tip and estimate its effective curvature.
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Robertson, R. E., T. J. Chu, R. J. Gerard, J. H. Kim, M. Park, H. G. Kim, and R. C. Peterson. "Three-dimensional fiber reinforcement shapes obtainable from flat, bidirectional fabrics without wrinkling or cutting. Part 2: a single n-sided pyramid, cone, or round box." Composites Part A: Applied Science and Manufacturing 31, no. 11 (November 2000): 1149–65. http://dx.doi.org/10.1016/s1359-835x(00)00120-2.
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Druchinin, Denis, Maksim Gnusov, Nikolay Borodin, Andrey Milyaev, and Mihail Voskoboinik. "RESEARCH DEVELOPMENT OF FORCE CUTTING OF SEEDLING ROOTS BY THE BLADE OF THE WORKING BODY OF PLANT LIFTERS." Forestry Engineering Journal 11, no. 1 (March 30, 2021): 111–22. http://dx.doi.org/10.34220/issn.2222-7962/2021.1/10.
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Large-sized woody plants are widely used in forestry and forest parks. This type of planting material, which has certain advantages over ordinary seedlings and seedlings in the form of better preservation and survival rate, prolonging the planting season and reducing the volume of preparatory work, is transplanted with a soil lump using special equipment. Research has being carried out to create equipment for digging out large-sized plants with a lump of soil. Previously, laboratory experiments were carried out to assess the effort of cutting the roots of tree species with blades of various configurations. The obtained data made it possible to determine the optimal geometric parameters of the cutting edge of the blade - the sharpening angle is 30 ° and the angle at the apex of the oblique blade is 105 °. However, this configuration of the cutting element did not always provide a cut of the root system without damage. This paper presents further improvement of the design of plant lifters and the development of research on power cutting of root wood with cutting elements of various profiles. During the experiments, we used blades with the following cutting edge shape: horizontal, providing horizontal cutting with a flat wedge, as well as oblique and arcuate for sliding cutting. According to the research results, it was determined that the smallest cutting force is provided by the use of a blade with an arcuate cutting edge. It has been established that this blade configuration in combination with a cutting edge sharpening angle of 30 ° allows cutting the roots with minimal squeezing and cracking of their surface
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Tsai, M. Y., and James C. Sung. "Dressing Behaviors of PCD Conditioners on CMP Polishing Pads." Advanced Materials Research 76-78 (June 2009): 201–6. http://dx.doi.org/10.4028/www.scientific.net/amr.76-78.201.
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Diamond pad conditioner or dresser can determine the efficiency of chemical mechanical polishing (CMP) processes and the quality of polished wafers. Conventional diamond pad conditioners are made by adhering discrete diamond grits on a flat substrate. The size distribution of diamond grits coupled with the deformation of the substrate often make the tips of diamond grits lying at different heights. Instead of attaching individual diamond grits to a metal substrate, a revolutionary design of pad conditioners is based on carving a structure out of sintered polycrystalline diamond (PCD) matrix. The PCD dresser is manufactured by wire electro discharge machining to form cutting pyramids of a specific size with a designed shape. The dressing characteristics of pad surface textures are studied by comparison with conventional diamond pad conditioner. Experimental results indicate that the PCD dresser can dress asperities of the pad more uniformly than the conventional diamond dresser due to PCD dresser having identically shaped tip and the same height diamond. In addition the cutting rate of PCD dresser for IC1000 pad not only is reduced by about 30% but also it can dress pad more effectively than conventional diamond dresser.
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Massah, Jafar, Fatemeh Hassanpour Roudbeneh, Zeinab Hassanpour Roudbeneh, and Keyvan Asefpour Vakilian. "EXPERIMENTAL INVESTIGATION OF BIONIC SOIL-ENGAGING BLADES FOR SOIL ADHESION REDUCTION BY SIMULATING ARMADILLIDIUM VULGARE BODY SURFACE." INMATEH Agricultural Engineering 60, no. 1 (April 30, 2020): 99–106. http://dx.doi.org/10.35633/inmateh-60-11.
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Soil adhesion is a physical phenomenon which results in undesirable effects including increment in drag force and energy consumption of cutting or tillage tools. One method to reduce the soil adhesion is biomimetics, i.e., focusing on the technique soil-burrowing animals’ benefit. In this study, three types of blade were designed and built: flat blade, corrugated blade and a combination of flat and corrugated blades. The corrugated blade was simulated from Armadillidium vulgare body surface geometrical shape. Experimental results showed that in dry soil, flat and corrugated blades required similar drag force while the combined blade showed higher drag force requirements. In wet soil, the corrugated blade resulted in the lowest drag force, which was due to faster movement of soil layer on the blade surface. Drag force of the corrugated blade was lower than the half of the drag force of two other blades at travel speed of 0.04 m/s. Besides, the drag force of corrugated blade decreased by increasing the blade travel speed. Furthermore, in wet soil, the energy consumption of the corrugated blade at the travel speeds of 0.02 and 0.04 m/s was 66% and 83% lower than the flat blade, respectively.
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Choy, P. K., J. Atkinson, and T. Dias. "A New Technique for Feeding Yarn in a Flat Bed Knitting Machine." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 209, no. 2 (August 1995): 151–54. http://dx.doi.org/10.1243/pime_proc_1995_209_242_02.
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The quality of knitted fabric panels is of considerable importance to the knitwear industries. The latest development in flat bed knitting technology improves the efficiency of the production by knitting fully fashioned fabric panels that are to exact shape and size. This greatly reduces the cutting waste and length of time for the making-up process, but garment manufacturers are still facing the difficulty of retaining dimensional stability of the knitted panels. One of the significant factors influencing this undesired property is input yarn tension variation. The analysis of this problem is described and a new method of yarn feeding is also suggested. This method utilizes storage yarn feed to eliminate the undesired effect of yarn feed speed variation and has been applied as a prototype. The results show a promising and satisfactory improvement in the fabric quality.
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Li, Qian, Lanlan Xie, and Junping Li. "Modular Motion-Structure Design Model for Planetary Surface Sampling." International Journal of Aerospace Engineering 2019 (April 1, 2019): 1–15. http://dx.doi.org/10.1155/2019/5987306.
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Because there are less restrictions in space, a variety of different movement patterns and equipment structures may be used during the process of planetary surface sampling. Traditionally, the optimal analysis for surface sampling is focused on specific equipment structures and movements; in contrast, a new modular motion-structure design model for surface sampling, which is a more flexible model, is discussed in this paper. By establishing and combining two basic module groups, namely, the motion group and the structure group, this new design model can define and analyse multiple movement patterns and structures. For the motion group, calculating the sampling trajectory is the main purpose, in which there are two basic modules: tridimensional uniform rectilinear movements and tridimensional uniform circular movements. The two basic motion modules can be freely combined in a given coordinate system to simulate a random sampling trajectory. The structure group contains a series of curved and flat plates, which can be defined by a set of unified parameters (including section, extension, and cutting parameters). By assigning different values to these parameters, the curved or flat plates can represent different external shapes. The different structures of the various pieces of surface sampling equipment can be simulated by combining these different plates. In addition to defining these basic modules, analysing the coupling among different modules, which can be simplified to the relationship between velocity and surface, plays an important role in establishing this design model. Based on the modular design theory, this new model will not only reduce the difficulty of analysis but also improve accuracy for planetary surface sampling.
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Petrovic, A., L. Lukic, S. Ivanovic, and A. Pavlovic. "Optimisation of tool path for wood machining on CNC machines." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 231, no. 1 (August 9, 2016): 72–87. http://dx.doi.org/10.1177/0954406216648715.
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Peripheral pocket or contour milling in wood machining, using flat end milling tool, can be performed with different tool paths. Technology designers of multi axis CNC wood machining use their experience and intuition to choose some of the options offered by CAM systems that determine the final shape of tool path, thus the generated tool path largely depend on individual judgment. Minimum cutting force, maximum dynamic stability of the process and minimum tool wear are achieved, or some other technological requirements are met, by using optimal tool path. Tool path optimisation is based on analysis of possible tool paths and determination of cutting parameters which are dependable of chosen tool path and are affecting the main wood processing factors. Axial and radial depth of cut, engagement angle, feed and feed rate profile are identified as key parameters dependable of tool path, and their values and variations along the tool path influence the cutting speed, tool wear and cutting force. Knowledge of values and changes of those key machining parameters along the tool path is necessary for simulation and monitoring of the main cutting factors during the wood machining process. NC code transformation methodology and generation of tool path parameters necessary for calculating all elements needed for tool movement simulation from given NC programs are shown. Blank and tool mathematical description are used with tool movement information for simulation of wood machining process. Simulation of cutting parameters and their variation along the tool path, presented in this paper, can be used as bases for development of methodology for choosing the most adequate tool path for wood machining of given contour considering minimum cutting force and cutting force variation, minimum tool wear, maximum productivity or some other criteria.
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Pan, Qie, Dong Hua Jiang, and Wu Min Lin. "The Study and Design of the Wood Horniness Alloy Milling Cutter CAD System." Advanced Materials Research 430-432 (January 2012): 1839–42. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.1839.
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Milling cutter can process the plane, shaped exterior, rabbet, mortise and many kinds of technologic hubs in the processing of wood cuttings and be widely used in many milling machines, planers and planers of four sides. Horniness alloy milling cutter is diffusely employed in lot of countries for the more durable grade compare to the other alloy cutter. As the course of market globalization and economic incorporation quicken, competition in manufacturing become serious. In order to win the competition, shorten the design time and increase the design reliability, CAD technology is necessary to use in the design of complex cutting-tools. The technology logical and efficiency quality of the cutter affect straightway the precision and the cost of the manufacture. Accordingly, cutting-tool CAD/CAPP/CAM integration comes true, and benefit of cutting-tool enterprise is improved. The contents of the research include: Aiming at the present design actuality in the WHAMC in china, the general design ideas and schemes of WHAMC CAD system are put forward. The completely research has been fulfilled in the functional module of the designing, intensity proofing, configuration and outputting of the drawing of the WHAMC CAD system. The floor rabbet cutter is the example in this part. This paper has analyzed the structure characteristics of the floor rabbet cutter, established the calculation of the floor rabbet cutter, parameter database of drawing, the basement of developing the marketable WHAMC CAD and discussed the probability of comprehensive development of the marketable WHAMC CAD software. The paper is developed by using the Auto CAD as the development flat and the LISP language as the development language by comparing and analyzing and performs functions of each design module of the system. The system provides man-machine conversation on the inputting parameters.
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Kasijanto, Kasijanto, Sadar Wahjudi, Listiyono Listiyono, and Muhammad Fakhruddin. "Pengaruh Parameter Pemesinan terhadap Kualitas Hasil Potong Mesin Bubut Maximat V13 pada Benda Kerja Poros PVC." Jurnal Energi dan Teknologi Manufaktur (JETM) 2, no. 02 (December 31, 2019): 19–24. http://dx.doi.org/10.33795/jetm.v2i02.43.
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Metal cutting process (cutting process) is to cut metal to get the shape and size and quality of the planned cutting surface. The metal cutting process is carried out with special tools, according to the type of cutting process. So the tools for one process cannot be used in another process, even for similar processes, the tools cannot be exchanged if the cutting plans are not the same. Lathe process is a machining process to produce cylindrical machine parts which are carried out using a Lathe. Its basic form can be defined as the machining process of the outer surface of cylindrical or flat lathe objects. Polyvinyl Chloride, commonly abbreviated as PVC, is the third-order thermoplastic polymer in terms of total usage in the world, after Polyethylene (PE) and Polypropylene (PP). Worldwide, more than 50% of PVC produced is used in construction. PVC is produced by polymerizing vinyl chloride monomers (CH2 = CHCl). Because 57% of its mass is chlorine, PVC is the polymer that uses the lowest petroleum feedstock among other polymers. This research follows up the selection of configuration of the lathe machining process using plastic work pieces. In this study, Maximat V13 lathe and PVC type plastic were used. The variation of machining processes are spindle rotation (320, 540, and 900 rpm), feeding speed (0.07, 0.14, and 0.28), the use of tool types (carbide and HSS) and cooling (without cooling, coolant, and oil). So, with this research, it is expected that the optimal parameters in determining the configuration of the lathe machining process on a PVC work piece to produce a good turning surface can be achieved
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Benthien, Jan T., and Martin Ohlmeyer. "Effects of Flat-Shaped Face Layer Particles and Core Layer Particles of Intentionally Greater Thickness on the Properties of Wood-Reduced Particleboard." Fibers 8, no. 7 (July 13, 2020): 46. http://dx.doi.org/10.3390/fib8070046.
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Against the background of the intention to reduce the amount of wood used in the production of particleboard for economic reasons, the associated reduction in panel density and consequently the panel properties, the influence of the alternative use of flat-shaped face layer particles and core layer particles of intentionally greater thickness on the panel properties was investigated. Appropriate particles were made for this purpose, panels with typical (650 kg/m3) and reduced wood usage (500 kg/m3) were produced, and e.g., their bending properties and internal bond strength were determined. Particle size characterization was done with sieve analysis, image analysis (length and width measurement), and manual thickness gauging. It was found that the alternative use of the flat-shaped particle significantly increased the bending properties and thus the level of the reference can be achieved despite the reduced use of wood. The reason for the increased bending properties was assumed to be the higher strength of the particles themselves and the more effective adhesive bond between the particles. The increase in internal bond strength when using alternative particles could be attributed solely the different production history (e.g., use of fresh cutting blades and laboratory scale production).
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Yang, F., and I. Kao. "Interior Stress for Axisymmetric Abrasive Indentation in the Free Abrasive Machining Process: Slicing Silicon Wafers With Modern Wiresaw." Journal of Electronic Packaging 121, no. 3 (September 1, 1999): 191–95. http://dx.doi.org/10.1115/1.2792683.
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In wiresaw manufacturing processes, such as those in slicing silicon wafers for electronics fabrication, abrasive slurry is carried by high-speed wire (5 to 15 m/s), which exerts normal load to the surface via hydrodynamic effects and bow of taut wire. As a result, the abrasives carried by slurry are constrained to indent onto and roll over the surface of substrate. In this paper, the axisymmetric indentation problem in the free abrasive machining (FAM) is studied by modeling a rigid abrasive of different shapes pushing onto an elastic half space. Based on the harmonic property of dilatation, the closed-form solution of stress distribution inside the cutting material for three different indentation processes in common FAM process are presented: cylindrical and conical abrasives as well as uniform pressure distribution. Along the symmetrical axis, von-Mises stress is two times larger than that of local maximum shear stress for all three indentation conditions. The von-Mises stress is infinity at the contact point for sharp pointed indentation, a location of crack initiation and nucleation. For indentation by abrasive of flat surface, which also can be provided by the localized effects due to the hydrodynamic pressure acting on the surface, both the von-Mises and local maximum shear stress reach maximum underneath the contact zone.
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Węgrzynkiewicz, Sylwia, Joanna Waś-Solipiwo, Maciej Hajduga, Marta Anna Hajduga, and Maciej Błażej Hajduga. "The Influence of Cutting Metal Elements on the Structure and Corrosion Resistance of the Zn Coating." Materials Science Forum 844 (March 2016): 159–66. http://dx.doi.org/10.4028/www.scientific.net/msf.844.159.
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The aim of the research was the indication of the causes of a difference in thickness of the zinc coating on the surface shaped by plasma cutting. The research was focused on fittings for overhead power lines - a double eyes links made of steel S355J2. The prepared materials were cut by plasma. Then, links were subjected to mechanical treatment (shot-blasting) and chemical treatment (pickling, rinsing and fluxing). The hot-dip galvanizing process was performed in industrial conditions by applying the constant temperature equal to 457°C, and a dipping time equal to 150 s. The research was conducted on the link’s flat surface (after rolling) and the side surface (after cutting). The (Zn) - coating morphologies and sub-layer thicknesses were evaluated on the basis of metallographic analysis and corrosion tests (acc. to EN ISO 9227). The correlation between the results of corrosion test and coatings morphology was determined.The observed changes are closely related to the outer layer steel structure (HAZ) which subsequently influences the mechanism and zinc coating growth kinetics
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Russo, Alessandro, Silvio Caravelli, Massimiliano Mosca, Mauro Girolami, Alessandro Ortolani, Simone Massimi, Mario Fuiano, and Stefano Zaffagnini. "Piezosurgery in Hallux Valgus Correction: Distal Linear Osteotomy Operative Technique Using Piezoelectric Tools." Joints 07, no. 01 (March 2019): 025–30. http://dx.doi.org/10.1055/s-0039-3401821.
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Abstract Purpose Piezoelectric and ultrasonic vibrations have been used to cut tissues for three decades, in particular, in periodontics. The increasing use of piezosurgery is based on its clinical advantages such as selective cutting, precision, and low-temperature work rates. The authors applied this concept to a new operative field, the foot and ankle pathology and surgery, such as hallux valgus corrective distal linear osteotomy. Methods The osteotome equipped was the Surgysonic Moto-II model (Esacrom, Imola, Italy), a system recently developed for cutting bone withmicrovibrations. Tips used in author’s case series were a high-efficiency five teeth piezoelectric saw and a high-efficiency flat scalpel shaped on three edges. Operative technique is described. Discussion and Conclusion Piezoelectric techniques were developed in response to the need for great precision and safety in bone surgery that was availavle with other manual and rmotorised instruments. Piezo-technology allows minimally-invasive and percutaneous surgery, with reduced trauma on periostium, bone, and soft tissues, reduced healing time of the osteotomy due to the absence of bony necrosis and debris formation and major precision.
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Wojtkowiak, Dominik, and Krzysztof Talaśka. "The influence of the piercing punch profile on the stress distribution on its cutting edge." MATEC Web of Conferences 254 (2019): 02001. http://dx.doi.org/10.1051/matecconf/201925402001.
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Modifying the piercing punch profile may have a positive effect on the belt perforation process. Using the proper shape of the tool may reduce the perforation force and improve the quality of the holes. However, complex geometry of the punch can also cause an adverse stress distribution, which leads to a faster tool wear. In the presented paper, several different piercing punch profiles were tested using FEM analyses in ABAQUS and the obtained stress distributions along its cutting edges were analyzed. For the selected group of the piercing punches, the influence of variable geometrical features (a radius of rounding, an angle of chamfering or a depth of the bowl) on the stress distribution were also shown. Based on the results, it is possible to predict how modifying the punch profile will affect the shortening of the tool life, compared to the basic flat-end cylindrical piercing punch. The following research can be useful in the design process of the punching tools used for vacuum conveyor belts perforation.