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1
Morovič, Ladislav, Juraj Vagovský und Ivan Buranský. „Shape Investigation of Worn Cutting Inserts with Utilization of Active Triangulation“. Key Engineering Materials 581 (Oktober 2013): 22–25. http://dx.doi.org/10.4028/www.scientific.net/kem.581.22.
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The paper deals with utilization of active triangulation method for shape investigation of cutting inserts after wear. For measuring of cutting insert shape a method using the structured light (fringe projection) was used. As a measuring device the optical 3D scanner GOM ATOS II TripleScan SO was used. Cutting inserts with different shapes was measured. With the measurement method mentioned in the paper the accurate shape of the cutting insert can be captured. From the 3D model moreover it is possible to measure the geometrical properties as well as tool wear, plastical deformation, build-up-edge, corner damage and chipping of cutting insert.
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Shrirao, Pankaj, Hanumant Jagtap, Pramod Magade, Pitambar Gadhave und Dnyaneshwar Kamble. „Thermo-hydraulic Analysis of Fluid Flowing Through Circular Pipe with Wire Mesh Inserts having Varying Mesh Porosity“. IOP Conference Series: Earth and Environmental Science 1285, Nr. 1 (01.01.2024): 012028. http://dx.doi.org/10.1088/1755-1315/1285/1/012028.
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Abstract The experimental investigation was made to analysis the rate of heat transfer of fluid flowing through a heat exchanger with varying wire-mesh porosity inserts. The Nusselt number (Nu), friction factor (f), and overall heat transfer rate (Q) were evaluated using experiments. Three different wire mesh inserts of square, hexagonal and diamond porosity were examined. The SS 316 stainless wire mesh with a porosity of 9 pores per inch (PPI) were inserted normal to the flow field with a pitch distance of 5 cm for each shape of wire mesh. The experiments were conducted on test rig with air as a working fluid for turbulent flow regime having Reynolds number ranging from 6,000 to 16,000. Experiments were performed on computerized test rig with heated air flowed in one direction through inner pipe and counter flow cold water flowing through the outer concentric pipe. The circular inner pipe of 40 cm long having 4 cm inner diameter (Di), and 3 mm thick was used for experimentation. The experimental results showed that Nusselt number (Nu) increases with decrease in friction factor (f) with increase in Reynolds number (Re). Also, it is observed that the hexagonal porosity shape of wire mesh insert provides higher material contact and gain more energy absorption from hot air resulted in improvement in heat transfer coefficient as compared to diagonal and square porosity shapes of wire mesh inserts, under similar operating conditions. The friction factor and pressure drop for square porosity shape of wire mesh insert is higher as compared to hexagonal and diagonal porosity shapes of wire mesh inserts respectively. This is due to the fact that square porosity wire mesh provides more obstruction in the flow field compared with hexagonal and diagonal porosity shapes of wire mesh inserts. The hexagonal porosity shape of wire mesh insert provides better option for heat exchange applications.
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Ahmed, Md Shamim, und Mohammad Zoynal Abedin. „Review on Heat Transfer Enhancement by Insert Devices“. International Journal of Engineering Materials and Manufacture 5, Nr. 4 (20.10.2020): 130–47. http://dx.doi.org/10.26776/ijemm.05.04.2020.03.
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The scientists revise the heat transfer enhancement techniques time to time to achieve better performance and to obtain optimized designs of heat exchangers. The present study reviews the performance and techniques of heat transfer enhancement using various insert devices such as twisted tape and wire coil insert as well as completely different forms of other inserts like air-foil shape inserts, X-shaped twisted tape inserts, baffles and V-winglets inserts with various types of medium and nanofluids. According to the summary of recent significant researches on the heat transfer enhancement by using different types of inserts and combinations of these inserts with various nanofluids showed that insert can indicatively enhance the heat transfer rate by modifying its geometry or configurations like twist ratio, length ratio, pitch ratio, segmented tape, perforated tape, angle of arrangements and insert quantities and so on which caused a considerable impact on performance characteristics of heat transfer enhancement along with the pressure drop and friction factor. It is revealed through reviewing the related literature that the highest value of equivalence heat transfer enhancement is as maximum as 400%, 300% and 9% for the twisted tape insert with helical tube, the air foil shaped inserts and for the wire coil inserts, respectively when compared with the smooth tube. In the case of baffles in nanofluids, as maximum as 255% equivalence heat transfer enhancement could be achieved when compared with that of baffles without nanofluids.
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Stafford, Myra, Robert L. Geneve und Jack W. Buxton. „Marigold Root Growth in 12-cm Containers Modified with Two or Four Copper-treated Inserts“. HortScience 31, Nr. 4 (August 1996): 679f—680. http://dx.doi.org/10.21273/hortsci.31.4.679f.
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This study evaluated the effect of container shape and copper hydroxide on root and shoot development of marigold (Tagetes patula `Little Devil Flame') seedlings. Containers were modified in shape and volume by gluing triangular polycarbonate inserts vertically onto sides of the container. The inserts were either painted with copper or not painted. Inserts decreased container volumes (no insert = 480 cm3, two inserts = 340 cm3, and four inserts = 200 cm3). After 38 days the seedling roots were scanned for computer analysis, and leaf area and dry weights were determined. Copper effectively prevented roots from growing in contact with copper treated surfaces. Shoot dry weight and leaf area were greater with no inserts, but if inserts were treated with copper the shoot dry weight and leaf area were greater. Root dry weight was reduced 7%–10 % with two inserts and 20% with four inserts compared to no inserts. Copper treated inserts reduced the dry weight further. However, at the insert interface, root length was increased between 15%–20% by all copper treatments, with the greatest increase in the four-insert treatment.
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Yang, Jin, Can Weng, Jun Lai, Tao Ding und Hao Wang. „Molecular Dynamics Simulation on the Influences of Nanostructure Shape, Interfacial Adhesion Energy, and Mold Insert Material on the Demolding Process of Micro-Injection Molding“. Polymers 11, Nr. 10 (27.09.2019): 1573. http://dx.doi.org/10.3390/polym11101573.
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In micro-injection molding, the interaction between the polymer and the mold insert has an important effect on demolding quality of nanostructure. An all-atom molecular dynamics simulation method was performed to study the effect of nanostructure shape, interfacial adhesion energy, and mold insert material on demolding quality of nanostructures. The deformation behaviors of nanostructures were analyzed by calculating the non-bonded interaction energies, the density distributions, the radii of gyration, the potential energies, and the snapshots of the demolding stage. The nanostructure shape had a direct impact on demolding quality. When the contact areas were the same, the nanostructure shape did not affect the non-bonded interaction energy at PP-Ni interface. During the demolding process, the radii of gyration of molecular chains were greatly increased, and the overall density was decreased significantly. After assuming that the mold insert surface was coated with an anti-stick coating, the surface burrs, the necking, and the stretching of nanostructures were significantly reduced after demolding. The deformation of nanostructures in the Ni and Cu mold inserts were more serious than that of the Al2O3 and Si mold inserts. In general, this study would provide theoretical guidance for the design of nanostructure shape and the selection of mold insert material.
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Vignesh, Ganesan, Debabrata Barik, Samraj Aravind, Ponnusamy Ragupathi und Munusamy Arun. „Numerical investigation of dimple-texturing on the turning performance of hardened AISI H-13 steel“. International Journal for Simulation and Multidisciplinary Design Optimization 13 (2022): 10. http://dx.doi.org/10.1051/smdo/2021043.
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Forming micro-dimples nearer to the cutting edge on the rack face of the tungsten carbide cutting inserts will positively influence the machinability. However, it is challenging to machine the perfect micro-dimple dimensions by utilizing the available machining techniques. Finite element analysis can be an efficient way to observe the influence of dimple-texture area density, micro-dimple size, and various micro-dimple shapes on cutting inserts' machinability. This paper numerically analyses the impact of micro-dimple-textured cutting inserts in dry machining of AISI H-13 steel using AdvantEdge (virtual machining and finite element analysis software). Micro-dimples are formed on the rack face of tungsten carbide cutting inserts to observe the effect of dimple-textured cutting inserts on machinability compared to non-textured cutting inserts in terms of micro-dimple shape, micro-dimple size, and micro-dimple area density ratio. Their outcomes are analysed in terms of chip-insert contact length, main cutting force, and thrust force. It is observed that micro-dimple textured cutting inserts exhibit minimal main cutting force and thrust force in line with increasing the cutting insert life span. The abrasive wear was reduced in dimple-textured cutting inserts due to minimal contact between the cutting insert and chip developed compared to non-textured cutting inserts.
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Struzikiewicz, Grzegorz. „Application of 3D Imaging for Analyzing the Chip Groove Shapes of Cutting Inserts“. Applied Sciences 14, Nr. 7 (08.04.2024): 3134. http://dx.doi.org/10.3390/app14073134.
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An effective chip formation process is significant for an efficient metal-cutting process. Long continuous chips can lead to scratches on the machined surface, increasing the risk to operator safety and stability of the machining process. The use of chip grooves on cutting inserts allows for control of the chip formation and breaking process during machining. The shape of the rake surface and the design of the chip groove also affect the efficiency of the machining process. The article presents the use of 3D imaging to analyze changes in the selected chip groove shapes depending on the cutting depth ap = 0.10, 0.25, and 0.50 mm and the angular location of the cutting insert relative to the machined surface of the workpiece (i.e., major cutting-edge angle K = 60° and K = 90°). The analysis methodology was based on the use of 3D image registration and surface shape modeling. In the analysis based on the 3D imaging presented, the novelty was the adaptation of methods typically used to map and model the terrain surface, which have not been used previously in cutting processes. The evaluation of the shape of the chip groove surface was carried out using, e.g., watershed maps and 3D surface maps. The obtained results indicated a significant influence of the cutting depth and major cutting-edge angle on the surface shape, profile, and length of the chip former; chip groove volume; and the theoretical contact area of the formed chip with the cutting insert. It was observed that for small depths of cut, i.e., ap < 0.25 mm, the chip-curling process may be difficult due to the flattened shape of the rake surface. In addition, the influence of the convexity of the rake surface of the cutting insert on the chip formation process was demonstrated. The results of the experimental research that verified the conclusions are presented. The developed results may be useful in the process of selecting the parameters and conditions of the metal finishing through use of tools with a shaped rake surface.
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Sun, Bao Jun, und Xi Wu Fang. „The Optimization of Edge-Shape Parameter for Curve-Edge Milling Insert Based on Thermal-Mechanic Coupling Physical Field“. Advanced Materials Research 308-310 (August 2011): 1665–68. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.1665.
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The edge shape of milling insert has important influence on the heat loading and mechanical loading during metal cutting. The optimization of edge-shape parameter for curve-edge milling insert based on evaluation criteria of thermal-mechanic coupling field was carried out in order to improve the thermal-mechanic coupling field and to raise lifetime and production rate of milling insert. A new edge shape function was obtained. The curve-edge milling insert was designed driven by the edge function. The coupling field of milling insert has obvious improvement by finite element analysis (FEM). The maximal equivalent stress and displacement in cutting deformation area decreased by 17.2% and 15.7% respectively.
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Papadakis, Loucas, Stelios Avraam, Demetris Photiou, Simona Masurtschak und Juan Carlos Pereira Falcón. „Use of a Holistic Design and Manufacturing Approach to Implement Optimized Additively Manufactured Mould Inserts for the Production of Injection-Moulded Thermoplastics“. Journal of Manufacturing and Materials Processing 4, Nr. 4 (24.10.2020): 100. http://dx.doi.org/10.3390/jmmp4040100.
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Injection moulding is one the most familiar processes for manufacturing of plastic parts by injecting molten thermoplastic polymers into a metallic mould. The cycle time of this process consists of the phases of injection, packing, cooling, and ejection of the final product. Shortening of cycle time is a key consideration to increase productivity. Therefore, in this manuscript the adoption of additively manufactured mould inserts with conformal cooling channels by means of selective laser melting (SLM) with the aim to reduce process cycles is presented. The design and manufacture of a mould insert with conformal cooling channels for producing pressure fitting thermoplastic parts is described. Numerical analysis of the injection process and simulation of shape distortions after SLM were conducted providing useful results for the design and manufacture of the mould insert. The results of the numerical analyses are compared with experimental 3D geometrical data of the additively manufactured mould insert. Temperature measurements during the real injection moulding process demonstrating promising findings. The adoption of the introduced method for the series production of injection moulded thermoplastics proves a shortening of cycle times of up to 32% and a final product shape quality improvement of up to 77% when using mould inserts with conformal cooling channels over the conventional mould inserts.
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Valdez, Dustin, Jami Fukui, Thomas Wolfgruber, Lambert Leong, Gertraud Maskarinec und John Shepherd. „Abstract P3-01-13: Comparing portable and clinical ultrasound systems using 3D printed breast phantom inserts“. Cancer Research 82, Nr. 4_Supplement (15.02.2022): P3–01–13—P3–01–13. http://dx.doi.org/10.1158/1538-7445.sabcs21-p3-01-13.
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Abstract Background: Late-stage breast cancer rates in the Pacific where mammography services are limited are exceedingly high. Therefore, alternative accessible breast cancer screening technologies such as portable ultrasound is needed. However, little is known about the performance of portable ultrasound when compared to clinical ultrasound for use in breast cancer screening. By utilizing 3D printing technology, it is possible to design breast phantom inserts to replicate various types of lesions. In this study, we utilized 3D printed breast phantom inserts to compare portable and clinical ultrasound lesion detection performance. Methods: Four different breast inserts were designed using FreeCAD (version 0.19) to replicate different lesion detection properties. The first insert compares lesion shape, the second insert investigates depth and size, the third insert looks at fiber diameter, and the fourth insert looks at clusters. The four inserts were printed using a photopolymer resign (Formlabs Inc Rigid resign, Somerville, MA, USA) and then placed in a gelatin-based breast phantom designed for ultrasound use. Using the portable ultrasound (GE Vscan Extend) and clinical ultrasound (Philips EPIQ 5G), various images were captured of identical angle and orientation for both devices. The number of lesions visualized were counted and presented as a percentage of lesions detected. Results: The portable ultrasound had a 100% lesion detection rate for breast insert 1, 90.3% for breast insert 2, 70% for breast insert 3 and 55.8% for breast insert 4. Clinical ultrasound had 100% lesion detection rate for breast insert 1, 93.1% for breast insert 2, 76.6% for breast insert 3, and 99% for breast insert 4. Conclusion: Portable ultrasound shows comparable lesion detection capabilities to clinical ultrasound in 3 of the 4 breast phantom insert tests. Portable ultrasound may have potential as a capable accessible breast cancer screening device in areas without mammography. Citation Format: Dustin Valdez, Jami Fukui, Thomas Wolfgruber, Lambert Leong, Gertraud Maskarinec, John Shepherd. Comparing portable and clinical ultrasound systems using 3D printed breast phantom inserts [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-01-13.
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Anagonye, Aloysius U., und David A. Stephenson. „Modeling Cutting Temperatures for Turning Inserts With Various Tool Geometries and Materials“. Journal of Manufacturing Science and Engineering 124, Nr. 3 (11.07.2002): 544–52. http://dx.doi.org/10.1115/1.1461838.
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Temperatures are of interest in machining because cutting tools often fail by thermal softening or temperature-activated wear. Many models for cutting temperatures have been developed, but these models consider only simple tool geometries such as a rectangular slab with a sharp corner. They do not simultaneously account for tool nose radii and insert shape effects, even though it is known in practice that these features affect tool life and thus presumably tool temperature. This report describes a finite element study of tool temperatures in cutting that accounts for tool nose radius and included angle effects. A temperature correction factor model that can be used in the design and selection of inserts is developed to account for these effects. Parametric mesh generator is used to generate the finite element models of tool and inserts of varying geometries. The steady-state temperature response is calculated using NASTRAN solver. Several finite element analysis (FEA) runs are performed to quantify the effects of insert’s included angle, nose radius, and materials for the insert and the tool holder on the cutting temperature at the insert rake face. The FEA results are then utilized to develop a temperature correction factor model that accounts for these effects. The temperature correction factor model is integrated with an analytical temperature model for rectangular inserts to predict cutting temperatures for contour turning with inserts of various shapes and nose radii. Finally, experimental measurements of cutting temperature using tool-work thermocouple technique are performed and compared with the predictions of the new temperature model. The comparisons show good agreement.
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Mogaji, Taye Stephen, Emmanuel Tolulope Idowu und Tien-Chien Jen. „Numerical Simulation for Comparative Thermo-Hydraulic Performance of Turbulent Flow in Tubes with Twisted Tape Inserts“. Journal of Engineering Science 16, Nr. 2 (10.12.2020): 71–100. http://dx.doi.org/10.21315/jes2020.16.2.4.
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This article focused on investigating numerically the effects of key design parameters including tape thickness, tube wall to tape edge clearance and three different perforated shapes cut (circular, triangular and pentagon) on the heat transfer coefficient enhancement in tube with twisted tape inserts. Water was considered as the working fluid under the turbulent flow of Reynolds number (Re) between 12,000 and 22,000, with constant wall temperature of the tubes. It is found that due to the swirling flow and efficient mixing of the fluid, all the tape inserts considered in this study produced better thermalhydraulic performance than the plain tube without an insert. At the same time, tape inserts with small tube wall to tape edge clearance and considerable thickness value is beneficial to reduce the friction factor, consequently enhancing the heat transfer rate. Through the thermal performance factor (TPF) evaluation, the twisted tape with perforated triangular shape cut has an advantage over the pentagon and circular shapes cut with increasing Re. A maximum TPF as high as 1.68 can be obtained for the twisted tape with perforated triangular shape cut under low turbulent Re.
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Shvets, S. V., und V. P. Astakhov. „Effect of Insert Angles on Cutting Tool Geometry“. Journal of Engineering Sciences 7, Nr. 2 (2020): A1—A6. http://dx.doi.org/10.21272/jes.2020.7(2).a1.
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An analysis of publications has shown that mechanically clamped indexable inserts are predominantly used in modern tool manufacturing. Each insert has its shape and geometry in the tool coordinate system. The static system’s required geometry is achieved by the tilting of the insert pocket in the radial and axial directions. Therefore, it is of great importance in the tool design to know the relationships between the insert’s geometry parameters in the tool coordinate system where the geometry paraments of the insert are defined and working geometry parameters of the tool defined in the static coordinate system. The paper presents the developed methodology for determining the insert pocket base surface position to ensure the required values of the tool geometry parameters of the selected indexable insert in the static coordinate system. The graphs of the dependence of each of the angles of the insert geometry on the angles of rotation of this insert in the front and profile planes are presented as the level lines for practical use. Using these graphs, one can optimize all geometric insertion parameters in the static coordinate system. The model of the calculations of the mechanism of the insert clamping by a screw is developed. The basic size and tolerance of the output link determine the distance from the intersection line of the base surfaces to the thread axis on the pocket and the minimum amount of the screw stroke on the insert clamping in the pocket. Keywords: indexable insert, cutting tool, coordinate system, base surfaces, geometric parameters.
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Bertsche, Dirk, Paul Knipper, Sebastian Meinicke, Konrad Dubil und Thomas Wetzel. „Experimental Investigation on Heat Transfer Enhancement with Passive Inserts in Flat Tubes in due Consideration of an Efficiency Assessment“. Fluids 7, Nr. 2 (24.01.2022): 53. http://dx.doi.org/10.3390/fluids7020053.
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This paper presents results of an experimental investigation on pressure drop and heat transfer for a wide range of Reynolds and Prandtl numbers ranging from 8 < Pr < 60 and 40 < Re < 3500, for flat tubes without and with passive inserts. For three different kinds of passive insert designs, the impact on heat and momentum transfer due to coaction of the total set of passive inserts with different shape and amount was investigated. Experimental results were analyzed regarding two main aspects: Heat transfer mechanisms and pressure drop induced by friction and form drag forces due to the presence of different shapes. After heat and momentum transfer mechanisms for each passive insert design were analyzed, heat transfer and pressure drop enhancement were compared to each other, leading to an efficiency discussion. Different concepts for efficiency evaluation, which are cited in literature, were applied to the presented experimental data. Pros and cons of the different concepts are discussed. Finally, we propose an equation for evaluation of total performance, which fully respects the energetic and exergetic aspects of heat transfer and pressure drop enhancement.
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Zhou, Fusheng, Ruodong Huang, Chao Gao, Yun Yang, Yajun Qiao, Chunchang Zhu und Tongchun Luo. „Abnormal Breakdown Process and Mechanism of High-performance Epoxy Insulation“. Journal of Physics: Conference Series 2228, Nr. 1 (01.03.2022): 012048. http://dx.doi.org/10.1088/1742-6596/2228/1/012048.
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Abstract In recent years, various faults caused by insufficient mechanical properties of high-performance epoxy insulating parts occur from time to time. The breakdown position is epoxy metal interface, in which an obvious mechanical failure form is found. It is speculated that the failure mechanism may be the failure process caused by combined electrical mechanical breakdown. An insulation failure of epoxy insulating parts was analysed and he similarities and differences of bending and tensile properties of single column leg of different batches of products was studied, which is used to put forward the bulk insulation failure process of epoxy insulating parts under mechanical electrical coupling. In this paper, the bending test and tensile test of single column leg of high-performance insulation are designed, and the bonding strength of column leg insert is studied and analyzed. It is found that the bonding strength of column leg inserts of high-performance insulating parts in the fault batch is insufficient and has great dispersion. The bonding strength of column leg inserts is mainly affected by the knurling shape, knurling width and the coating shape of semi-conductive adhesive on the surface of the insert.
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Bhattacharya, B., G. R. Tomlinson und J. R. House. „Vibration suppression of structures with viscoelastic inserts“. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 216, Nr. 10 (01.10.2002): 983–95. http://dx.doi.org/10.1243/095440602760400959.
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The concept of suppressing flexural and longitudinal wave motion in a free-free beam structure by use of embedded viscoelastic inserts is described. Taking the example of a simple aluminium beam it is shown that the shape of the insert in terms of the incident wave angle plays an important role in the efficient suppression of wave motion. The insert principle is then applied to a ‘top-hat’ stiffener section that forms part of a fibre-reinforced polymeric composite beam structure, typical of that used in the fabrication of marine structures. From this example it is shown that the use of specifically designed viscoelastic inserts can reduce flexural and longitudinal wave motion over a wide frequency range. The numerical studies are supported by experimental tests in the case of both the free-free beam and the more complex top-hat section structure.
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Ziemann, Christian, Maik Stille, Florian Cremers, Dirk Rades und Thorsten M. Buzug. „The effects of metal artifact reduction on the retrieval of attenuation values“. Journal of Applied Clinical Medical Physics 18, Nr. 1 (05.12.2016): 243–50. http://dx.doi.org/10.1002/acm2.12002.
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AbstractBackgroundThe quality of CT slices can be drastically reduced in the presence of high‐density objects such as metal implants within the patients’ body due to the occurrence of streaking artifacts. Consequently, a delineation of anatomical structures might not be possible, which strongly influences clinical examination.PurposeThe aim of the study is to clinically evaluate the retrieval of attenuation values and structures by the recently proposed Augmented Likelihood Image Reconstruction (ALIR) and linear interpolation in the presence of metal artifacts.Material and MethodsA commercially available phantom was equipped with two steel inserts. At a position between the metal rods, which shows severe streaking artifacts, different human tissue‐equivalent inserts are alternately mounted. Using a single‐source computer tomograph, raw data with and without metal rods are acquired for each insert. Images are reconstructed using the ALIR algorithm and a filtered back projection with and without linear interpolation. Mean and standard deviation are compared for a region of interest in the ALIR reconstructions, linear interpolation results, uncorrected images with metal rods, and the images without metal rods, which are used as a reference. Furthermore, the reconstructed shape of the inserts is analyzed by comparing different profiles of the image.ResultsThe measured mean and standard deviation values show that for all tissue classes, the metal artifacts could be reduced using the ALIR algorithm and the linear interpolation. Furthermore, the HU values for the different classes could be retrieved with errors below the standard deviation in the reference image. An evaluation of the shape of the inserts shows that the reconstructed object fits the shape of the insert accurately after metal artifact correction. Moreover, the evaluation shows a drop in the standard deviation for the ALIR reconstructed images compared to the reference images while reducing artifacts and keeping the shape of the inserts, which indicates a noise reduction ability of the ALIR algorithm.ConclusionHU values, which are distorted by metal artifacts, can be retrieved accurately with the ALIR algorithm and the linear interpolation approach. After metal artifact correction, structures, which are not perceptible in the original images due to streaking artifacts, are reconstructed correctly within the image using the ALIR algorithm. Furthermore, the ALIR produced images with a reduced noise level compared to reference images and artifact images. Linear interpolation results in a distortion of the investigated shapes and features remaining streaking artifacts.
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Islam, M. N., und A. Pramanik. „Effects of Insert Geometry and Feed Rate on Quality Characteristics of Turned Parts“. Journal of Advanced Manufacturing Systems 14, Nr. 03 (18.05.2015): 149–66. http://dx.doi.org/10.1142/s0219686715500109.
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This paper investigates experimentally and analytically the influence of insert geometry and feed rate on the quality characteristics of turned parts under the dry cutting condition. A three-level, three-parameter experiment was planned using the design of experiment methodology. The three levels of independent input parameters were: insert shape–rhombus, triangle, and square; nose radius 0.4, 0.8, and 1.2 mm; and feed rate–0.11, 0.22 and 0.33 mm/rev. The measured output parameters were the three most widely used quality characteristics of turned parts–diameter error, circularity and surface finish (arithmetic average). The results were analyzed using three methods: traditional analysis, Pareto analysis of variation and Taguchi method. The results reveal that two of the selected tool geometry parameters, insert shape and nose radius, influence diameter error considerably (total contribution 66.97%) and have minor effects on circularity (total contribution 3.67%) and surface finish (total contribution 11.60%). Feed rate is the major contributor to surface finish (76.42% contribution), whereas circularity is dominated by interaction effects such as insert shape–feed rate interaction (31.44% contribution).
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Pottmeyer, Florentin, Markus Muth und Kay André Weidenmann. „Research of the Load Bearing Capacity of Shape-Optimized Metal Inserts Embedded in CFRP under Different Types of Stresses“. Key Engineering Materials 742 (Juli 2017): 636–43. http://dx.doi.org/10.4028/www.scientific.net/kem.742.636.
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An efficient implementation of lightweight design is the use of continuous carbon fiber reinforced plastics (CFRP) due to their outstanding specific mechanical properties. Embedded metal elements, so-called inserts, can be used to join metal-based attachments to structural CFRP parts in the context of multi-material design. They differ from other mechanical fasteners and have distinctive benefits. In particular, drilling of the components to be joined can be avoided and, depending on the preforming, fiber continuity can be maintained using such elements. Thus, no local bearing stress is anticipated. Previous work published by the authors [1] dealt with a systematic research of the influence of different types of stresses on the load bearing capacity of welded inserts. This contribution aims at the investigation of the performance of shape-optimized inserts under the same types of loading to compare with the results of the welded inserts serving as a reference. For that purpose, the respective load bearing capacities were evaluated after preinduced damages from impact tests and thermal cycling. In addition, dynamic high-speed tensile tests (pull-out) were conducted under different loading velocities. It is shown that the load bearing capacities increased up to 19% for high velocities (250 mm/s) in comparison to quasi-static loading conditions (1.5 mm/min) showing an obvious strain rate dependency of the CFRP. Quasi-static residual strength measurements under tensile loading identified the influence of the respective preinduced damages of the insert. Influence of the thermal loading condition was evaluated by placing the specimens in a climate chamber and exposing it to various numbers of temperature cycles from-40 °C to +80 °C with a duration time of 1.5 hours each. Here, it turned out that already 10 temperature cycles decreased the quasi-static load bearing capacity up to 31%. According to DIN EN 6038 the specimens were loaded with different impact energies and the residual strength were measured carrying out pull-out tests. It could be shown that the damage tolerance is significantly lower for the shape-optimized insert due to failure-critical delamination. The optimized insert also endured lower impact energies and the influence on the performance was higher.
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Hwang, D. Y., und W. A. Foster. „Axisymmetric Free Vibration of Shallow Spherical Shells With a Circular Rigid Insert“. Journal of Pressure Vessel Technology 115, Nr. 2 (01.05.1993): 207–9. http://dx.doi.org/10.1115/1.2929517.
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A general solution for the third-order partial differential equations for the axisymmetric free vibration of thin isotropic shallow spherical shells with a rigid insert is presented in this paper. The frequency equation in terms of Bessel functions as well as modified Bessel functions is solved for the fundamental vibrational frequency and mode shape. Both linear and non-linear boundary conditions are applied and the results are compared. The relationship between the vibrational frequency, mode shape and the size of the rigid insert is discussed.
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Paschoalinoto, Nelson Wilson, Ed Claudio Bordinassi, Roberto Bortolussi, Fabrizio Leonardi und Sergio Delijaicov. „The effect of process parameters and cutting tool shape on residual stress of SAE 52100 hard turned steel by high speed machining“. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 235, Nr. 1-2 (25.06.2020): 290–300. http://dx.doi.org/10.1177/0954405420929788.
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This study focused on determining the residual stress of SAE 52100 hard-turned steel. The objective was to evaluate and compare the effects of the cutting-edge geometry and cutting parameters (cutting speed, feed rate, and cutting depth) on the residual stresses of three different conventional inserts: S-WNGA08 0408S01020A 7025, T-WNGA08 0408T01020A 7025, and S-WNGA432S0330A 7025. Tests were performed on 60 samples of SAE 52100 hardened steel with an average hardness of 58.5 HRC. The circumferential residual stresses of the samples were measured by X-ray diffraction. A full factorial design of experiments with three factors and two levels each with two central points and a replicate was used for a statistical analysis. The most significant results were as follows: For all inserts, the measured residual stresses were compressive, which extended the tool lifespan. The residual stresses of the Type-S inserts were significantly influenced by the cutting speed and depth, and those of the Type-T insert were significantly influenced by the feed rate and cutting depth. In addition, the residual stresses of the insert 3 were more compressive than those of the other two types of inserts. In other words, residual stresses are more compressive for inserts with larger chamfer angles even as the principal residual stress profiles were all compressive. This work has also shown that it is possible to determine a significant statistical relationship between cutting forces and residual stresses, allowing force measurements to predict the residual stress without any information on process parameters.
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Nguyen, Nhu-Tung. „A development method of cutting force coefficients in face milling process using parallelogram insert“. EUREKA: Physics and Engineering, Nr. 5 (13.09.2021): 36–52. http://dx.doi.org/10.21303/2461-4262.2021.001890.
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This paper presents a modeling method of cutting force and a combination approach of theory and experimental methods in the determination of cutting force coefficients in the face milling process using a parallelogram insert. By the theoretical method, the cutting forces were modeled by a mathematical function of cutting cutter geometry (Cutter diameter, the number of inserts, the insert nose radius, insert cutting edge helix angle, etc.), cutting conditions (depth of cut, feed per flute, spindle speed, etc.), and cutting force coefficients (shear force coefficients, edge force coefficients). By the theoretical method, the average cutting forces in three directions (feed – x, normal – y, and axial – z) were modeled as the linear functions of feed per flute. By the experimental method, the average cutting forces in these three directions were also regressed as the linear functions of feed per flute with quite large determination coefficients (R2 were larger than 92 %). Then, the relationship of average cutting forces and feed per flute was used to determine all six cutting force coefficient components. The validation experiments were performed to verify the linear function of average cutting forces, to determine the cutting force coefficients, and to verify the cutting force models in the face milling process using a cutter with one parallelogram insert. The cutting force models were successfully verified by comparison of the shape and the values of predicted cutting forces and measured cutting forces. These proposed methods and models can be applied to determine the cutting force coefficients and predict the cutting force in the face milling process using a parallelogram insert and can be extended with other cutting types or other insert types
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Shi, Li Min, und Cheng Yang. „Cutting Temperature Experiment and Simulation Analysis of the Complex Groove Turning Insert“. Materials Science Forum 861 (Juli 2016): 44–49. http://dx.doi.org/10.4028/www.scientific.net/msf.861.44.
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In order to study the complex groove inserts in the cutting process caused by temperature variation of cutting,Using multi factor cutting method and combined with finite element simulation technology, from cutting parameters and chip-breaking groove two aspects influence on cutting temperature and cutting force cutting tests were carried out and experimental study on the complex groove turning insert edge chamfering, rounded cutting edge radius on cutting temperature effects. Also tested the effects of temperature on the chip shape cutting and breaking, and analyzed the temperature on the Influence law of cutting tool wear, thus providing a theoretical basis for tool wear.
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Kudryashov, E. A., I. M. Smirnov und D. V. Grishin. „Selecting the Shape of the Insert in a Lathe Cutter“. Russian Engineering Research 39, Nr. 12 (Dezember 2019): 1046–49. http://dx.doi.org/10.3103/s1068798x1912013x.
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MANTLER, ANDREA, und HELEN CAMERON. „CONSTRUCTING RED-BLACK TREE SHAPES“. International Journal of Foundations of Computer Science 13, Nr. 06 (Dezember 2002): 837–63. http://dx.doi.org/10.1142/s0129054102001497.
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Cormen et al. describe efficient algorithms for inserting nodes into and deleting nodes from red-black trees. If some binary trees satisfying the definition of red-black trees cannot be built by these algorithms, then theoretical analyses of red-black trees that consider all binary trees satisfying the definition of red-black trees may not accurately describe the behavior of red-black trees in practice. We show that any binary tree shape that satisfies the definition of red-black trees can be built using only the insertion algorithm, RB-INSERT, of Cormen et al. We first describe an algorithm, RB-SHAPE, which, given any red-black tree T, will construct an insertion sequence for T. When the constructed sequence of insertions is performed on the empty tree using RB-INSERT, the result is a red-black tree with the same shape as T. We then prove the correctness of algorithm RB-SHAPE.
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Zhang, Min, Jia-Yu Wang, Jian Su, Jian-Jun Wang, Shi-Tong Yan, Yi-Chao Luan und Cheng-Kung Cheng. „Wear Assessment of Tibial Inserts Made of Highly Cross-Linked Polyethylene Supplemented with Dodecyl Gallate in the Total Knee Arthroplasty“. Polymers 13, Nr. 11 (02.06.2021): 1847. http://dx.doi.org/10.3390/polym13111847.
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Background: the wear of tibial insert is still one of primary factors leading to failure of total knee arthroplasty (TKA). Dodecyl gallate (DG) has shown improvements in the oxidation stability of highly cross-linked polyethylene (HXLPE). This study aimed to assess the application of HXLPE supplemented with DG (HXLPE-DG) on the tibial insert in TKA concerning the wear resistance and the potential impact on implant fixation; Methods: tibial inserts made of HXLPE-DG were subjected to a 3 million loading-cycle wear test following ISO 14243-1:2009. The loss of mass and wear rate of the tibial inserts were calculated. The quantity, size,- and shape of wear particles were recorded; Results: the test specimens lost an average mass of 16.00 mg ± 0.94 mg, and were on an average wear rate of 3.92 mg/million cycles ± 0.19 mg/million cycles. The content of wear particles in the calf serum medium was 3.94 × 108 particles/mL ± 3.93 × 107 particles/mL, 96.66% ± 0.77% of the particles had an equivalent circular diameter less than 0.5 μm. The aspect ratio of wear particles was 1.40 (min: 1.01; max: 6.42). Conclusions: HXLPE-DG displayed advantages over the commonly used materials for tibial inserts and presented the potential of application in TKA.
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Piska, Miroslav, und Katerina Urbancova. „Advanced Machining of Joint Implant UHMWPE Inserts“. Machines 10, Nr. 11 (01.11.2022): 1008. http://dx.doi.org/10.3390/machines10111008.
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The modern orthopaedic implants for applications in hips, knees, shoulders, and spines are composed of hard metal alloys or ceramics and a tribological sub-component that is made of soft materials, with good frictional properties—e.g., UHMWPE (Ultra High Molecule Weight Polyethylene). The UHMWPE implants need to be machined into their final shape after the polymerization and consolidation into a blank profile or near net shaped implant. Thus, machining is a crucial technology that can generate an accurate and precise shape of the implant that should comply with the joints’ function. However, the machining technology can affect the topography and integrity of the surface, transmitted stresses, and resistance to wear. Technology, cutting tools, and cutting conditions can have an impact on the physical and mechanical properties of the entire implant and its longevity. This paper shows an effective and competitive technology for acquiring high-quality insert shape, dimensions, and surface, needed especially for customized implants.
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Kazakov, Kirill E., und Svetlana P. Kurdina. „Wear problem for tube with thin nonuniform inner coating and rigid insert with complex profile“. E3S Web of Conferences 243 (2021): 02008. http://dx.doi.org/10.1051/e3sconf/202124302008.
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The article describes the formulation of the problem of wear of an elastic pipe with a nonuniform internal coating by a rigid insert, the diameter of which is variable. For this problem, a mathematical model is built, which is a mixed integral equation. The resulting integral equation contains functions related to the variable properties of the coating and the shape of the insert. When constructing an analytical solution, a special approach was used, since standard methods do not allow taking into account the presence of rapidly changing functions in the equation, which can describe the shapes and properties of materials. In the resulting solution, the functions describing the variable properties of the coating and the profile of the insertion are separated by separate terms. This allows you to always get accurate results.
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Hussin, Radhwan, Safian Sharif, Shayfull Zamree Abd Rahim, Allan Rennie, Mohd Azlan Suhaimi, Abdellah El-hadj Abdellah, Norshah Afizi Shuaib, Mohd Tanwyn Mohd Khushairi und Aurel Mihail Titu. „Irregular Shape Effect of Brass and Copper Filler on the Properties of Metal Epoxy Composite (MEC) for Rapid Tooling Application“. Journal of Manufacturing and Materials Processing 6, Nr. 6 (02.11.2022): 134. http://dx.doi.org/10.3390/jmmp6060134.
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Due to their low shrinkage and easy moldability, metal epoxy composites (MEC) are recognized as an alternative material that can be applied as hybrid mold inserts manufactured with rapid tooling (RT) technologies. Although many studies have been conducted on MEC or reinforced composite, research on the material properties, especially on thermal conductivity and compressive strength, that contribute to the overall mold insert performance and molded part quality are still lacking. The purpose of this research is to investigate the effect of the cooling efficiency using MEC materials. Thus, this research aims to appraise a new formulation of MEC materials as mold inserts by further improving the mold insert performance. The effects of the thermal, physical, and mechanical properties of MEC mold inserts were examined using particles of brass (EB), copper (EC), and a combination of brass + copper (EBC) in irregular shapes. These particles were weighed at percentages ranging from 10% to 60% when mixed with epoxy resin to produce specimens according to related ASTM standards. A microstructure analysis was made using a scanning electron microscope (SEM) to investigate brass and copper particle distribution. When filler composition was increased from 10% to 60%, the values of density (g/cm3), hardness (Hv), and thermal conductivity (W/mK) showed a linear upward trend, with the highest value occurring at the highest filler composition percentage. The addition of filler composition increased the compressive strength, with the highest average compressive strength value occurring between 20% and 30% filler composition. Compressive strength indicated a nonlinear uptrend and decreased with increasing composition by more than 30%. The maximum value of compressive strength for EB, EC, and EBC was within the range of 90–104 MPa, with EB having the highest value (104 MPa). The ANSYS simulation software was used to conduct a transient thermal analysis in order to evaluate the cooling performance of the mold inserts. EC outperformed the EB and EBC in terms of cooling efficiency based on the results of thermal transient analysis at high compressive strength and high thermal conductivity conditions.
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Rasulov, A., und U. Dalabaev. „Flow in a channel with porous insert“. IOP Conference Series: Earth and Environmental Science 990, Nr. 1 (01.02.2022): 012027. http://dx.doi.org/10.1088/1755-1315/990/1/012027.
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Abstract Filtration of an incompressible liquid (gas) in a non-deformable porou s medium is investigated. The results of numerical simulation of the hydrodynamic features of the flow arising after the passage of the liquid through a layer of an immobile porous medium are presented. An interpenetrating model of multiphase media is used to describe such flows. The porosity and permeability of the porous medium, as well as the force of interfacial interaction, are considered in the framework of compliance with the Kozeny-Karman ratio. The influence of the geometrical shape of the bulk layer on the nature and magnitude of the inhomogeneity of the flow velocity behind the obstacle is shown. Considering the shape of the porous medium significantly affects the flow parameters. Numerical simulation results are compared with experimental data. The effects of the non-uniformity of the fluid velocity field arising from the curvature of the layer surface and the influence of the arising inhomogeneity on the velocity are investigated by the methods of a computational experiment. A qualitative comparison is made of velocity inhomogeneities when a fluid flows through a porous obstacle. For the numerical implementation of the filtration equation of the interpenetrating model, a SIMPLElike algorithm was used.
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Chan, Kuen Cheong, und Li Min Zhou. „Static Behaviours of Carbon Fibre Composite Strip with Bifurcated Type Shape Memory Alloy Pins“. Key Engineering Materials 334-335 (März 2007): 1153–56. http://dx.doi.org/10.4028/www.scientific.net/kem.334-335.1153.
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A numerical study of the static behaviours of composite strip with bifurcated type shape memory alloy pins has been conducted. The case of bifurcated type shape memory alloy pins inserted inside the composite strip around the hole to reinforce the laminate, which was subjected to the axial stress was simulated. The models for stress analysis were established by using ANSYS finite element programme. Two types of shape memory alloy pins were proposed to insert along the through thickness direction of the carbon fibre woven fabric composite strip to induce the clamping force. The pre-tensioned load was applied to the shape memory alloy pins in order to reduce occurrence of delamination in the laminate. Three-dimensional elements and contact elements were used to simulate the contact between the composite laminate and shape memory alloy pin to investigate the stress distribution around the hole in the composite strip. The effect of pre-strain of shape memory alloy on the stresses inside composite was studied. The results show that the stress characteristics of the button-shaped and bifurcated shape memory alloy pin models are similar; however, the stresses for the button-shaped pin model are lower. The tensile and compressive stresses, both in button-shaped and bifurcated pin models, are strongly dependent on the percentage of pre-strain of the shape memory alloy. It is therefore concluded that the shape memory alloy pin method was significantly reduced the stress concentration of the composite strip laminate.
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Lin, Heng Sheng, Sheng Chi Tsai, Yuan Chuan Hsu, Ming Che Hsiao, Chia Chou Ke und Bean Yin Lee. „A Design of Forming Dies for a Manifold of Airbag Inflator“. Advanced Materials Research 328-330 (September 2011): 849–52. http://dx.doi.org/10.4028/www.scientific.net/amr.328-330.849.
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The manifolds of airbag inflator were used to be produced by sheet-metal forming. It comprised at least eleven forming stages to achieve its final shape. Uneven wall thickness and poor dimensional accuracy were the common defects because the planar anisotropy of sheet-metal caused earing on the cup rim. In this study, the cup-shape workpiece is obtained from backward-extrusion of billets, followed by two stages of end-forming of tube and three stages of hole-piercing. During the end-forming production, the tool life of the first forming stage was the most severe because it applies close-die forging to increase its rim thickness. Therefore, in addition to the design of prestressed die insert, special attendance is paid to the partition of the die insert to further alleviate the stress level. The optimization of die insert was aided by the finite element analysis of DEFORM software. The results show that by lowering the parting line, the stress level can be minimized. The tool life can therefore be improved.
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Tamri, Norjamalullail, Rozli Zulkifli, Che Husna Azhari und Albert Uchenna Ude. „Fibre Insert Mould for Injection Moulding“. Jurnal Kejuruteraan si3, Nr. 1 (30.09.2020): 51–57. http://dx.doi.org/10.17576/jkukm-2020-si3(1)-08.
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Insert moulding is equivalent to over-moulding. Both processes are achieved by inserting different materials into one another in the same mould to improve product’s capability. This process will increase the value of a resulting product because of the additional material price, material insertion process and cycle time. Such moulding process directly increases the overall price of a product but the price is cheaper compared with that of other processes or materials that have the same shape and strength. This insert moulding process requires two moulding materials. The first material is coated by the injected material, which then becomes solid and hardens to cover the second material. In general, the second material is placed permanently in the mould section. When the mould is closed, the injection moulding process is performed. The parts placed in the mould are made of metal, which will attach and reinforce the product. Dumbbell-ready injection is released along with kenaf yarn content in the middle, which is called the fibre insert mould. The fibre insertion technique is conducted by finding the problem of fibre. Then, the small fibre is cut while inside the barrel (either through moulding or compounding). Yarn-shaped fibres are placed on the core of a mould and clamped. Subsequently, a plastic material is injected into the mould. Consequently, the tensile strength of polypropylene (PP) will increase by 55%. A cheaper material (kenaf yarn) can increase the strength of the PP through an easier and cheaper process. The number of processes is reduced from three (before: cutting > compounding > moulding then finished) to two (after: insert and moulding then finished).
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Senthilkumar, N., Azhagiri Pon und T. Tamizharasan. „A Finite Element Simulation Study on Effects of Variation in Machining and Geometrical Parameters in Turning“. Applied Mechanics and Materials 592-594 (Juli 2014): 3–7. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.3.
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In this work, the influence of variation in machining parameters cutting speed, feed rate and depth of cut and geometrical parameters cutting insert shape (included angle), relief angle and nose radius is studied using DEFORM-3D, a finite element simulation software. The cutting tool inserts of various geometries are evaluated to study its performance for varying conditions considering contact temperature and mean stress. Effect of individual parameter is analyzed by varying its value by three different level values, while the other parameter values are set at the optimum condition, likewise for all input parameters. From the results obtained, it is observed that the performances of cutting inserts are good at the optimum level of parametric values than at the other level values.
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Nor, Fethma M., Joong Yeon Lim, Mohd Nasir Tamin, Ho Yong Lee und D. Kurniawan. „Effects of Starter Defect on Energy Release Rate of Three-Point End-Notch Flexure Tested Unidirectional Carbon Fiber Reinforced Polymer Composite“. Polymers 12, Nr. 4 (14.04.2020): 904. http://dx.doi.org/10.3390/polym12040904.
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The mechanics of damage and fracture process in unidirectional carbon fiber reinforced polymer (CFRP) composites subjected to shear loading (Mode II) were examined using the experimental method of the three-point end-notch flexure (3ENF) test. The CFRP composite consists of [0o]16 with an insert film in the middle plane for a starter defect. A 3ENF test sample with a span of 50 mm and interface delamination crack length of 12.5 mm was tested to yield the load vs. deformation response. A sudden load drop observed at maximum force value indicates the onset of delamination crack propagation. The results are used to extract the energy release rate, GIIC, of the laminates with an insert film starter defect. The effect of the starter defect on the magnitude of GIIC was examined using the CFRP composite sample with a Mode II delamination pre-crack. The higher magnitude of GIIC for the sample with insert film starter defect was attributed to the initial straight geometry of the notch/interface crack and the toughness of the resin at the notch front of the fabricated film insert. The fractured sample was examined using a micro-computerized tomography scanner to establish the shape of the internal delamination crack front. Results revealed that the interface delamination propagated in a non-uniform manner, leaving a curved-shaped crack profile.
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Gross, Robert S., und James G. Goree. „Torsion of a Rigid Smooth Elliptic Insert in an Infinite Elastic Plane“. Journal of Applied Mechanics 58, Nr. 2 (01.06.1991): 370–75. http://dx.doi.org/10.1115/1.2897195.
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A solution is presented for the non-Hertzian contact stress problem developed during torsion of a smooth rigid elliptic insert in an infinite, linearly elastic plane. The problem is reduced to a singular integro-differential equation which is solved numerically. Results are presented for the contact zones, and for the normal and tangential stresses at the plane-insert interface. The contact region is independent of the magnitude of the applied moment, but depends strongly on the shape of the ellipse, and is weakly dependent on Poisson’s ratio of the plane. Results are also given for the reduction in torsional stiffness between a fully bonded insert and the present solution, (i.e., a completely failed bond).
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Szablewski, Piotr, Stanisław Legutko, Adrian Mróz, Dariusz Garbiec, Rafał Czajka, Krzysztof Smak und Bartłomiej Krawczyk. „Surface Topography Description after Turning Inconel 718 with a Conventional, Wiper and Special Insert Made by the SPS Technique“. Materials 16, Nr. 3 (19.01.2023): 949. http://dx.doi.org/10.3390/ma16030949.
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This paper presents a comparison of surface morphology obtained after machining Inconel 718 by the conventional insert, by Wiper insert and by using the cutting insert made by Spark Plasma Sintering (SPS). The shape of the special insert was obtained by employing Wire Electrical Discharge Machining (WEDM). The paper focuses on the description of surface topography after turning in dry and wet conditions. The performed investigation included longitudinal turning tests of Inconel 718 performed in a range of variable feeds. Surface topography measurements have been performed with the application of Nanoscan 855. The performed analysis includes a parametric evaluation of the obtained surfaces. With the Wiper insert, the Sa surface roughness parameter was obtained below 0.6 µm in the whole range of used feed rates. The surface roughness parameter Sa measured on the surface after machining by special insert depends on the cutting conditions (wet and dry machining). After, the dry machining parameter Sa, similar to the Wiper insert, was below 0.6 µm in the whole range of used feed rates. Unfortunately, cutting Inconel 718 using special insert with feed rate f = 0.25 mm/rev and cooling generated a surface with Sa parameter over 2 times higher than for the same feed rate without cooling, while this parameter, after turning by conventional insert, increases over 4 times using feed rate f = 0.25 mm/rev compared to feed rate f = 0.05 mm/rev during machining with cooling. This ratio is lower for conventional insert in dry machining because of sticking, which arises at the smallest feed rate according to previous research.
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Alassane, SY. „Coupling Shape Optimization and Topological Derivative for Maxwell Equations“. Abstract and Applied Analysis 2022 (18.11.2022): 1–10. http://dx.doi.org/10.1155/2022/2425990.
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The paper deals with a coupling algorithm using shape and topological derivatives of a given cost functional and a problem governed by nonstationary Maxwell’s equations in 3D. To establish the shape and topological derivatives, an adjoint method is used. For the topological asymptotic expansion, two examples of cost functionals are considered with the perturbation of the electric permittivity and magnetic permeability. We combine the shape derivative and topological one to propose an algorithm. The proposed algorithm allows to insert a small inhomogeneity (electric or magnetic) in a given shape.
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Kobashi, Syoji, Nao Shibanuma und Yutaka Hata. „Fuzzy Visual Hull Algorithm for Three-Dimensional Shape Reconstruction of TKA Implants from X-Ray Cone-Beam Images“. Journal of Advanced Computational Intelligence and Intelligent Informatics 14, Nr. 2 (20.03.2010): 122–27. http://dx.doi.org/10.20965/jaciii.2010.p0122.
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Three-Dimensional (3-D) shape reconstruction of total knee arthroplasty (TKA) implantsin vivoplays a key role to investigate implanted knee kinematics. TKA implants typically consist of metal femoral and tibial components and a polyethylene tibial insert. X-ray computed tomography (CT) causes severe metal artifacts, making the 3-D shape in reconstructed images extremely difficult to understand. This article proposes a new method of 3-D reconstruction from X-ray cone-beam images. Called a fuzzy visual hull, it introduces fuzzy logic in recognizing X-ray images. X-ray cone-beam images are fuzzified and back-projected into a fuzzy voxel space. Defuzzifying the fuzzy voxel space enables the 3-D TKA implant shape to be reconstructed. The results of evaluation using TKA implantsin vitroand computer-synthesized images demonstrated that the fuzzy visual hull provides high robustness against noise added to X-ray cone-beam images. The new approach also reconstructed the 3-D polyethylene insert despite the difficulty of recognizing the region in conventional X-ray CT.
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Park, Joon-Koo, Choon-Man Lee und Dong-Hyeon Kim. „Investigation on the Thermal Effects of WC-Co Turning Inserts Deposited by Additive Manufacturing of Titanium Alloy Powder“. Metals 11, Nr. 11 (26.10.2021): 1705. http://dx.doi.org/10.3390/met11111705.
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Metal additive manufacturing (AM) has been one of the most useful processes in the manufacturing field. It has significant advantages in terms of the benefits of feature freedom and material waste reduction. These processes commonly use a heat source to fabricate a 3D shape through melting of a metal powder and subsequent solidification. The directed energy deposition method can stack the desired amount of material in the required location. This study addresses the thermal effects of a WC-Co cutting tool insert deposited by AM of titanium alloy powder in the turning process. First, the optimal deposition conditions were selected by conducting preliminary experiments. Second, titanium alloy powder was deposited on the turning insert under the selected conditions. Finally, verification evaluation was carried out in the turning process. The thermal effects of the turning insert with the titanium alloy were compared with an ordinary cutting tool insert. The average temperature of the cutting tool was reduced by 15% during operation.
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Huijgen, Willemijn H. F., Paul F. Gründeman, Tycho van der Spoel, Maarten-Jan Cramer, Paul Steendijk, Robert J. M. Klautz und Lex A. van Herwerden. „Resizable Ventricular Patch Plasty in the Porcine Left Ventricle a Pilot Study“. Innovations: Technology and Techniques in Cardiothoracic and Vascular Surgery 5, Nr. 1 (Januar 2010): 16–21. http://dx.doi.org/10.1097/imi.0b013e3181cfa8f1.
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Objective Endoventricular circular patch plasty is a method used to reconstruct the ventricular cavity in patients with (post) ischemic left ventricular aneurysm or global dilatation. However, late redilatation with mitral regurgitation has been reported, in which postoperative apex shape seems to play an important role. We studied the feasibility of ventricular volume downsizing with a variably shaped patch in porcine hearts. Methods In five in vitro and two acute animal experiments, a dyskinetic aneurysm was simulated with a pericardial insert. Reducing patch surface by changing patch shape diminished end-diastolic volume. In vitro, static end-diastolic volume was determined for each patch shape using volumetry and echocardiography. In the acute animal experiments, preliminary observations of patch behavior in live material were made, and pressure/time relationship, dPdTmax, was registered. Results In vitro, bringing the convex patch into a flat plane reduced LV volume from 66 ± 7 mL (aneurysm) to 49 ± 5 mL. Four of 5 patch shapes further reduced volume to a mean of 38 ± 7 mL (P = 0.03). The in vitro echocardiographic measurements correlated with volumetry findings (r = 0.81). In the acute animal experiments, dPdTmax varied with patch shape, independent of volume changes. Conclusions In this pilot study, in vitro shape configuration of the resizable ventricular patch resulted in a calibrated end-diastolic volume reduction. The data of the two in vivo pilot experiments clearly indicate that change in patch configuration in the situation of more or less unchanged end-diastolic volume had impact on cardiac performance. Future studies must substantiate the results of this observation.
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Eyercioglu, Omer. „Analysis of Dimensional Variations of Precision Gear Forging Die Geometry Due to Shrink Fit“. European Journal of Engineering and Formal Sciences 2, Nr. 3 (29.12.2018): 87. http://dx.doi.org/10.26417/ejef.v2i3.p87-95.
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The usual way to shrink fit design for precision forging dies are made by thick wall cylinder approach; i.e., taking the pitch diameter of the gear as bore diameter of the die insert without considering gear tooth shape. However, the compressive pre-stress due to the shrink fitting causes dimensional variations on the gear profile of the die insert. The dimensional accuracy of the final product is dependent on the accuracy of the gear die. Therefore, the dimensional variations due to shrink fit must be pre-determined and the gear tooth profile on the die insert modified accordingly. In this study, the dimensional variations of the precision spur gear forging die because of shrink fitting are analyzed by finite element method and the results are compared with the experimental ones. The results show that the FE model is successful to simulate the cylindrical die and agree well with thick wall cylinder approach and the experimental measurements. However, both the experimental measurements and the finite element results of gear die predict much higher radial displacements than the results of cylindrical die. Therefore, the determination of shape change of the gear die profile is beyond the capability of the thick wall cylindrical approach.
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UTSUMI, Daisuke, Masahiro KUSAKA und Masaaki KIMURA. „134 Selection Precept of Insert Piece Shape for Autocompleting Friction Welding Method“. Proceedings of the Materials and processing conference 2007.15 (2007): 81–82. http://dx.doi.org/10.1299/jsmemp.2007.15.81.
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KIMURA, Masaaki, Yosuke ISHINO, Masahiro KUSAKA und Koichi KAIZU. „Examination of Insert Piece Shape for Joint of Low Carbon Steels using Brass Insert Piece by Autocompleting Friction Welding Method“. QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY 30, Nr. 2 (2012): 149–57. http://dx.doi.org/10.2207/qjjws.30.149.
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Shin, Kwang Ho, Young Moo Heo und Jong Deok Kim. „The Development of Small Size Double Side Metal Plate with Internal Structure Utilizing Metal Injection Molding Process“. Applied Mechanics and Materials 365-366 (August 2013): 1132–35. http://dx.doi.org/10.4028/www.scientific.net/amm.365-366.1132.
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In this study, it is focused to make a double side metal plate with internal structure. The stainless steel powder (17-4PH 15F) was used in PIM process. PE(HDPE and LDPE) and PP were used to make the sacrificed insert with honeycomb structure using plastic injection molding process. And then these sacrificed insert parts were inserted at metal injection mold and metal injection molding process was carried out to build green part with rectangular shape. Subsequently, de-binding and sintering process were adopted. The dimensional contraction was occurred about 15.5% in width direction and about 16.2% in thickness direction.
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Singh, Bhanu Pratap, Vijay Singh Bisht, Prabhakar Bhandari und K. S. Rawat. „Thermo-Fluidic Modelling of a Heat Exchanger Tube with Conical Shaped Insert having Protrusion and Dimple Roughness“. Aptisi Transactions on Technopreneurship (ATT) 3, Nr. 2 (08.09.2021): 13–29. http://dx.doi.org/10.34306/att.v3i2.200.
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In the present work, thermo-fluidic behavior of a heat exchanger tube with conical shaped insert has been investigated with the help of finite volume method. To enhance the heat transfer rate, two different types of roughness has been used in conical insert i.e. protrusion and dimple roughness. A three-dimensional computational model with RNG turbulence model is used for the simulation and it has been performed for three different diameters (3 mm, 6 mm and 9 mm) and two different pitch space (120 mm and 180 mm) for both protrusion and dimple roughness. The present model has been validated with Dittus-Boelter equation and with Blasius equation for Nusselt number and friction factor, respectively. For a constant heat flux of 1200 W/m2, effect of roughness, diameter and pitch on Nusselt number and friction factor has been predicted for Reynold number range of 5000 to 30000. From the result, it is found that, the protrusion shaped roughness has better thermal performance factor than dimple shape and diameter of 6 mm has performed better than 3 mm and 9 mm for both the cases of roughness due to favorable flow dynamics.
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Chen, Wanxin, Zhenyang Wang, Ruishuai Si, Ruiyu Li, Lingxuan Yang, Jianliang Zhang und Baojun Zhao. „Optimization of HIsmelt reactor parameters for efficient combustion and heat transfer by numerical simulation“. Metallurgical Research & Technology 121, Nr. 1 (2024): 108. http://dx.doi.org/10.1051/metal/2023085.
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HIsmelt, as one of the non-blast furnace ironmaking processes, is rapidly becoming a focus of attention in the steel industry due to its outstanding advantages in terms of low requirements for raw materials and short and environmentally friendly process. In HIsmelt, a reasonable inner shape of a smelting reduction vessel has an important influence on combustion and heat transfer through changing flow field. Therefore, in this study, the effects of HIsmelt reactor parameters including oxygen-lance insert depth, and smelting reduction vessel body height and throat angle on combustion and heat transfer are investigated through the numerical simulation of the flow field, temperature field, and CO2 concentration field inside smelting reduction vessel. The results show that the heat transfer effect is further improved when increasing the oxygen-lance insert depth because the U-shaped vortex affects a wider area. In addition, as the smelting reduction vessel body height increases and the throat angle decreases, the U-shaped vortex gradually moves away from the melt pool and increases the scouring of the sidewalls. The increased temperature difference and low CO2 concentration indicate that this change reduces the combustion and heat transfer efficiency.
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SUDER, JIRI, TOMAS KOT, ALAN PANEC und MICHAL VOCETKA. „ANALYSIS OF INCREASING THE FRICTION FORCE OF THE ROBOT JAWS BY ADDING 3D PRINTED FLEXIBLE INSERTS“. MM Science Journal 2021, Nr. 6 (15.12.2021): 5322–26. http://dx.doi.org/10.17973/mmsj.2021_12_2021127.
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3D printing technology plays a key role in the production of prototypes and final functional parts. The ability to produce almost any shape using this technology in combination with lightweight materials is often used to minimise the weight of the designed components. However, for some applications, such as robot gripper jaws, conventional most commonly used materials, such as PLA, may be unsuitable due to their low coefficient of friction on the material of the manipulated object, which in some cases may cause the object to slip in the robot jaws. This article describes a technical problem from practice, where a manipulated object made of steel material slipped in the printed PLA jaws of the robot during its working cycle. This work is devoted to increasing the friction force of the robot jaws by adding 3D printed soft inserts. Two insert surface shapes made of two flexible materials TPU 30D and TPE 88 are tested. The increase in friction force is measured on a measuring device with an industrial robot and a force measuring sensor. The most suitable type of inserts and material is then tested on a collaborative robot at its required working cycle. The results of this experiment are intended to help designers as a source of information or inspiration in designing similar applications.
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Биків, Н. З., П. В. Ясній und В. П. Ясній. „Modeling of mechenical behavior of reinforced concrete beam reinforced by the shape memory alloy insertion using finite elements method“. Сучасні технології та методи розрахунків у будівництві, Nr. 13 (22.08.2020): 24–34. http://dx.doi.org/10.36910/6775-2410-6208-2020-3(13)-03.
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One of the methods for improving the bearing capacity of the construction structures and engineering constructions is the application of construction materials with the improved strength and flexibility characteristics as well as the ability to disperse the vibration energy. It is of particular importance for the construction structures being in the seismic regions, which are under dynamic loading during their operation. The shape Memory Alloys (SMA) are promising materials, which can recover their original shape after uploading (the effect of superelasticity) or being under the temperature influence (the effect of shape memory) during many cycles of loading – unloading.
The mechanical behavior of a reinforced concrete beam with classical reinforcement and a reinforced concrete beam reinforced with inserts of superelastic Nitinol (Ni-Ti) is simulated by the finite element method. Beam dimensions: h=140 mm; b=80 mm; L=1200 mm. The beam is made of concrete of the С20/25 class, armature А400С 2Ø12mm L=1080 mm; mountings armature А240С 2Ø6mm L=1200 mm, reinforcing insert Ni-Ti 2Ø12 mm L=120 mm. Behavior simulation took place in the ANSYS Workbench 19 R2 PC environment. Reinforced concrete beam is divided into finite elements. Size of the Solid 186 elements for the armature 12,5 mm, for the mountings armature 40 mm. The size of the Solid 186 elements for the body of the beam was automatically selected by the software – 200 mm. In total, the reinforced concrete beam consisted of 22872 finite elements and 4730 nodes. Reinforced concrete beam with armature A400C is subjected to evenly distributed load on the plane 120×80 mm (Р = 20MPa). It is revealed that the transition of the yield strength in the simulated beam with armature А 400С occurs at a load of Р = 9MPa. Therefore, the study of the behavior of the reinforced concrete beam with classical reinforcement (armature A 400C) and the reinforced concrete beam reinforced with inserts of superelastic Nitinol (Ni-Ti) occurred when loading beams to the value of Р = 9MPa and their complete unloading. The insert of nickel-titanium (Ni-Ti) alloy replaced the plastically deformed section of the working reinforcement A400C, where the stresses exceeded the yield strength (σt 0.2 = 365 MPa).
The values of displacements, maximum stresses and residual stresses of the beams by compared. It was concluded that the inserts made of superelastic Ni-Ti alloy 16,9 times reduced the εres of the working reinforcement, increased the maximum displacement of the beam by 9,7%, increased the εmax by 47,8% compared to the working reinforcement А400C.
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Mabuchi, Yusuke, Fumihiro Itoigawa, Takashi Nakamura, Keiich Kawata und Tetsuro Suganuma. „High Precision Turning of Hardened Steel by Use of PcBN Insert Sharpened with Short Pulse Laser“. Key Engineering Materials 656-657 (Juli 2015): 277–82. http://dx.doi.org/10.4028/www.scientific.net/kem.656-657.277.
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Precision grinding is one of the important processes for finishing of hardened steel parts. However, the grinding process might be quite costly providing the parts with shape complexity should be finished because a number of production steps are needed. Also, this process has some environmental issues, such as disposal of a large amount of grinding sludge and grinding fluid. Precision cutting would become a better alternative process to reduce cost and environmental burden because process steps can be simplified by use of CNC machine tools with PcBN cutting insert if deterioration of cutting tool edge by wear and chipping can be suppressed for long duration. In this study, to improve performance of a PcBN cutting insert, such as wear resistance and defect resistance by the applying of pulse laser processing to sharpen cutting edge in order to realize substitution of cutting for grinding. Precision cutting experiments for hardened steel are conducted by use of the PcBN insert with sharp and tough edges processed by pulsed laser and, for comparison, by use of the PcBN insert ground with diamond wheel. From the results of cutting experiments, it was found that precision cutting with PcBN insert processed by pulsed laser can provide a steady cutting state for a long cutting duration, and a smooth finished surface comparable to precision grindings.