The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform
S Paul - One of the best experts on this subject based on the ideXlab platform.
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some studies on high pressure cooling in turning of ti 6al 4v
International Journal of Machine Tools & Manufacture, 2009Co-Authors: A K Nandy, M C Gowrishankar, S PaulAbstract:Abstract Titanium alloys are being increasingly employed in engineering and bio-medical applications, but their manufacturability via the cutting and grinding process is always a problem, which needs to be overcome. Inherent characteristics of Ti–6Al–4V alloy promote Rapid Tool Wear, which needs to be curbed in order to attain high efficiency in metal cutting. Conventional or low-pressure cooling method fail to effectively conduct away the heat generated in the cutting zone, which is responsible for short Tool life. High-pressure coolant jets were directed into the Tool–chip interface to sufficiently penetrate and change the thermal, frictional and mechanical conditions in the cutting zone. High-pressure cooling using neat oil and water-soluble oil was undertaken and its effects on machining evaluation parameters such as chip form, chip breakability, cutting forces, coefficient of friction, contact length, Tool life and surface finish of the finished workpiece were evaluated in comparison with those from the conventional cooling method. The results show that significant improvement in Tool life and other evaluation parameters could be achieved utilising moderate range of coolant pressure.
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effect of coolant pressure nozzle diameter impingement angle and spot distance in high pressure cooling with neat oil in turning ti 6al 4v
Machining Science and Technology, 2008Co-Authors: A K Nandy, S PaulAbstract:Though titanium alloys are being increasingly sought in a wide variety of engineering and biomedical applications, their manufacturability, especially machining and grinding imposes lot of constraints. Titanium alloys are readily machinable provided the cutting velocity is in the range of 30–60 m/min. To achieve higher productivity, if the cutting velocity is enhanced to 60–120 m/min and beyond, Rapid Tool Wear takes place diminishing the available Tool life. Tool Wear in machining of titanium alloys is mainly due to high cutting zone temperature localised in the vicinity of the cutting edge and enhanced chemical reactivity of titanium with the Tool material. Rapid Tool Wear encountered in machining of titanium alloys is a challenge that needs to be overcome. High pressure cooling in machining is a very promising technology for enhancing Tool life and productivity via appropriate cooling and lubrication. The present investigation is an attempt to study the effects of jet application parameters, i.e., cool...
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beneficial effects of cryogenic cooling over dry and wet machining on Tool Wear and surface finish in turning aisi 1060 steel
Journal of Materials Processing Technology, 2001Co-Authors: S Paul, Nikhil Ranjan Dhar, A B ChattopadhyayAbstract:Abstract High production machining of steel inherently generate high cutting temperature, which not only reduces Tool life but also impairs the product quality. Conventional cutting fluids are ineffective in controlling the high cutting temperature and Rapid Tool Wear. Further, they also deteriorate the working environment and lead to general environmental pollution. Attempts have already been initiated to control the pollution problem by cryogenic cooling which helps also in getting rid of recycling and disposal of conventional fluids. The present work deals with experimental investigation in the role of cryogenic cooling by liquid nitrogen jet on Tool Wear and surface finish in plain turning of AISI 1060 steel at industrial speed-feed combination by two types of carbide inserts of different geometric configurations. The results have been compared with dry machining and machining with soluble oil as coolant. The results of the present work indicate substantial benefit of cryogenic cooling on Tool life and surface finish. This may be attributed to mainly reduction in cutting zone temperature and favorable change in the chip–Tool interaction. Further, it was evident that machining with soluble oil cooling failed to provide any significant improvement in Tool life, rather surface finish deteriorated.
Deyuan Zhang - One of the best experts on this subject based on the ideXlab platform.
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effect of radial high speed ultrasonic vibration cutting on machining performance during finish turning of hardened steel
Ultrasonics, 2021Co-Authors: Zhenlong Peng, Xiangyu Zhang, Deyuan ZhangAbstract:Abstract Hardened steel has been widely used in the aviation and automotive fields owing to its unique properties. However, the poor machining performance for finishing hardened steel owing to low attainable cutting speeds and Rapid Tool Wear has become a bottleneck in the functional performance and range of applications. In this study, a radial high-speed ultrasonic vibration cutting (R-HUVC) process was adopted for improving the machining performance of finishing hardened steel. R-HUVC involves the use of radial ultrasonic vibrations which ensure the separation of the Tool and workpiece. The kinematics of R-HUVC were analyzed through a theoretical model, and its surface generation mechanisms in the intermittent cutting mode were studied. Then, finish turning experiments were conducted on the cutting force, surface roughness, and Tool life to validate its machining performance compared to that of conventional cutting (CC) for a wide range of finishing conditions. The experimental results showed that R-HUVC can realize a lower cutting force, longer Tool life, and better surface roughness compared to CC. It was verified that R-HUVC can be applied to high-speed machining for the finish turning of hardened steel because it improves the machining performance.
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study on rotary ultrasonic assisted drilling of titanium alloys ti6al4v using 8 facet drill under no cooling condition
The International Journal of Advanced Manufacturing Technology, 2017Co-Authors: Deyuan Zhang, Xinggang Jiang, Wei Qin, Daxi GengAbstract:Titanium alloys (Ti6Al4V) have been widely applied in modern aerospace industry as structural components due to their excellent mechanical and physical properties. Meanwhile, the drilling process is essential for machining the assembly holes of Ti6Al4V. However, Ti6Al4V is also a difficult-to-cut material owing to their low thermal conductivity and high chemical reactivity with many Tool materials during machining, which easily lead to Rapid Tool Wear, premature Tool failure, and poor machining quality. This has attracted wide attention of researchers. In recent years, the rotary ultrasonic-assisted drilling (RUAD) technology, as a novel machining method, has been found to be very effective in the machining of difficult-to-cut materials like nickel alloys and titanium alloys. This paper first introduced an 8-facet drill Tool and combined the advantages of RUAD to carry out a study on the drilling of Ti6Al4V under no cooling condition. The experimental results indicated that compared with the common drilling (CD) of Ti6Al4V, in RUAD process with the vibration amplitude of 10 μm, the thrust force, torque, cutting temperature near the drilled hole exit, surface roughness of drilled hole, expansion increment of hole diameter, and burr height of drilled hole exit decreased by 16.79 to 20.2 %, 31.5 to 33.6 %, 18.54 to 21.68 %, 24.87 to 25.36 %, 46.75 to 57.63 %, and 82.27 to 89.18 %, respectively; the excellent chip breakability and removal effect of chip evacuation, superior surface integrity of drilled hole, enhanced Tool cutting ability, and prolonged Tool life were obtained in RUAD. Furthermore, the experimental results also proved that the drilling technology of RUAD of Ti6Al4V using the 8-facet drill was feasible and the cutting effects were superior.
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feasibility study of the rotary ultrasonic elliptical machining of carbon fiber reinforced plastics cfrp
International Journal of Machine Tools & Manufacture, 2012Co-Authors: Jing Liu, Deyuan Zhang, Longgang Qin, Linsong YanAbstract:Abstract Carbon fiber reinforced plastics (CFRP) are used for various aircraft structural components because of their superior mechanical and physical properties such as high specific strength, high specific stiffness, etc. However, when CFRP are machined, Rapid Tool Wear and delamination are troublesome. Therefore, cost effective and excellent quality machining of CFRP remains a challenge. In this paper, the rotary ultrasonic elliptical machining (RUEM) using core drill is proposed for drilling of holes on CFRP panels. This method combines advantages of core-drill and elliptical Tool vibration towards achieving better quality, delamination free holes. The cutting force model and chip-removal phenomenon in ultrasonic elliptical vibration cutting are introduced and analyzed. The feasibility to machine CFRP for RUEM is verified experimentally. The results demonstrate that compared to conventional drilling (CD), the chip-removal rate has been improved, Tool Wear is reduced, precision and surface quality around holes is enhanced, delamination at hole exits has been prevented and significant reduction in cutting force has been achieved.
Nikhil Ranjan Dhar - One of the best experts on this subject based on the ideXlab platform.
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effect of high pressure coolant jet on cutting temperature Tool Wear and surface finish in turning hardened hrc 48 steel
Journal of Mechanical Engineering, 2015Co-Authors: Mozammel Mia, Nikhil Ranjan DharAbstract:Hard turning of harder material differs from conventional turning because of its larger specific cutting forces requirements. The beneficial effects of hard turning can be offset by excessive temperature generation which causes Rapid Tool Wear or premature Tool failure if the brittle cutting Tools required for hard turning are not used properly. Under these considerations, the concept of high-pressure coolant (HPC) presents itself as a possible solution for high speed machining in achieving slow Tool Wear while maintaining cutting forces at reasonable levels, if the high pressure cooling parameters can be strategically tuned. This paper deals with an experimental investigation of some aspects of the turning process applied on hardened steel (HRC48) using coated carbide Tool under high-pressure coolant, comparing it with dry cut. The results indicate that the use of high-pressure coolant leads to reduced surface roughness, delayed Tool flank Wear, and lower cutting temperature, while also having a minimal effect on the cutting forces.
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cutting temperature Tool Wear surface roughness and dimensional deviation in turning aisi 4037 steel under cryogenic condition
International Journal of Machine Tools & Manufacture, 2007Co-Authors: Nikhil Ranjan Dhar, M KamruzzamanAbstract:Abstract Machining of steel inherently generates high cutting temperature, which not only reduces Tool life but also impairs the product quality. Conventional cutting fluids are ineffective in controlling the high cutting temperature and Rapid Tool Wear. Further, they also deteriorate the working environment and lead to general environmental pollution. Cryogenic cooling is an environment friendly clean technology for desirable control of cutting temperature. The present work deals with experimental investigation in the role of cryogenic cooling by liquid nitrogen jet on cutting temperature, Tool Wear, surface finish and dimensional deviation in turning of AISI-4037 steel at industrial speed-feed combination by coated carbide insert. The results have been compared with dry machining and machining with soluble oil as coolant. The results of the present work indicate substantial benefit of cryogenic cooling on Tool life, surface finish and dimensional deviation. This may be attributed mainly to the reduction in cutting zone temperature and favorable change in the chip–Tool interaction. Further it was evident that machining with soluble oil cooling failed to provide any significant improvement in Tool life, rather surface finish deteriorated.
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beneficial effects of cryogenic cooling over dry and wet machining on Tool Wear and surface finish in turning aisi 1060 steel
Journal of Materials Processing Technology, 2001Co-Authors: S Paul, Nikhil Ranjan Dhar, A B ChattopadhyayAbstract:Abstract High production machining of steel inherently generate high cutting temperature, which not only reduces Tool life but also impairs the product quality. Conventional cutting fluids are ineffective in controlling the high cutting temperature and Rapid Tool Wear. Further, they also deteriorate the working environment and lead to general environmental pollution. Attempts have already been initiated to control the pollution problem by cryogenic cooling which helps also in getting rid of recycling and disposal of conventional fluids. The present work deals with experimental investigation in the role of cryogenic cooling by liquid nitrogen jet on Tool Wear and surface finish in plain turning of AISI 1060 steel at industrial speed-feed combination by two types of carbide inserts of different geometric configurations. The results have been compared with dry machining and machining with soluble oil as coolant. The results of the present work indicate substantial benefit of cryogenic cooling on Tool life and surface finish. This may be attributed to mainly reduction in cutting zone temperature and favorable change in the chip–Tool interaction. Further, it was evident that machining with soluble oil cooling failed to provide any significant improvement in Tool life, rather surface finish deteriorated.
Eiji Shamoto - One of the best experts on this subject based on the ideXlab platform.
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influence of clearance angle on micro nano structure fabrication in elliptical vibration cutting of hardened steel
International Journal of Nanomanufacturing, 2017Co-Authors: Jianguo Zhang, Norikazu Suzuki, Yilong Wang, Eiji ShamotoAbstract:Surfaces textured by sophisticated micro/nano structures can provide advanced and useful functions and features as compared with simply smooth surfaces. To promote widespread use of the structured surfaces, manufacturing technology of structured surfaces for ultra-precision dies and moulds made of hardened steel is absolutely essential. Conventional diamond cutting is not applicable to machining of steel due to Rapid Tool Wear and surface deterioration. On the other hand, elliptical vibration cutting (EVC) equipped with the ultra-precision amplitude control sculpturing method is considered as a potential candidate for the functional surface fabrication on steel materials. In this method, Tool geometry, especially the clearance angle, imposes a limit on the machinable part geometry due to the flank face contact to the target shape in the downhill machining. In order to clarify the influence of flank face contact on the machining accuracy and the Tool Wear, a series of theoretical and experimental investigations are conducted in this paper. A surface with micro sine-sweep profile is fabricated on hardened steel by applying the proposed amplitude control sculpturing method. It verified that the interference between flank face and fabricated structure causes not only the serious machining accuracy deterioration but also the serious Tool damage due to the enhancing of ploughing process.
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Elliptical vibration cutting of tungsten alloy molds for optical glass parts
CIRP Annals - Manufacturing Technology, 2007Co-Authors: N. Suzuki, Rei Hino, Makoto Haritani, Jihui Yang, Eiji ShamotoAbstract:Elliptical vibration cutting is applied to ultra-precision machining of tungsten alloy molds for optical glass parts in the present research. The tungsten alloy is expected as a new mold material instead of conventional ones such as sintered tungsten carbide and CVD-silicon carbide. However, it cannot be finished precisely by ordinary cutting because of Rapid Tool Wear, brittle fracture and adhesion to the Tool. Therefore, the ultrasonic elliptical vibration cutting is applied to the ultra-precision machining of tungsten alloy. Practical ultra-precision molds are obtained by the elliptical vibration cutting, and they are applied to glass molding successfully.
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ultraprecision micromachining of brittle materials by applying ultrasonic elliptical vibration cutting
International Symposium on Micro-NanoMechatronics and Human Science, 2004Co-Authors: Norikazu Suzuki, Makoto Haritani, S Masuda, Eiji ShamotoAbstract:Ultraprecision micromachining of brittle materials with a single point diamond Tool, which is extremely difficult due to brittle fracture and Rapid Tool Wear, is realized by applying 'Elliptical Vibration Cutting' technology, which has been developed by the authors. Ultraprecision micro grooving experiments for brittle materials such as sintered tungsten carbide, zirconia ceramics, calcium fluoride and glass, which have different material properties, are carried out to clarify the basic effects of the elliptical vibration on ductile micromachining process. As a result of the micro grooving experiments for the sintered tungsten carbide, it is confirmed that the ductile micro grooving without brittle fractures can be realized by applying the elliptical vibration cutting at a depth of cut of 1.9 /spl mu/m. The surface quality is improved as the vertical amplitude of the elliptical vibration becomes small as compared with the size of sintered grains. The micro fractures of the zirconia ceramics appear relatively similar to those of the sintered tungsten carbide, since they are both sintered materials and have similar material properties. Critical depth of cut for ductile micro machining of the calcium fluoride is increased significantly by applying the elliptical vibration cutting. Values of the critical depth and the types of fractures depend on the crystal orientations, as it is a single crystal material. The critical depth is also increased significantly for an amorphous material, glass, by applying the elliptical vibration cutting. It is considered that the improvements of critical depth and surface quality by the elliptical vibration cutting are caused by significant reduction in the thickness of workpiece material cut in each cycle of the elliptical vibration.
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Ultraprecision micromachining of hardened steel by applying ultrasonic elliptical vibration cutting
MHS2003. Proceedings of 2003 International Symposium on Micromechatronics and Human Science (IEEE Cat. No.03TH8717), 2003Co-Authors: N. Suzuki, Eiji Shamoto, A. Nakamura, K. Harada, M. Matsuo, M. OsadaAbstract:Ultraprecision micromachining of hardened steel with a single point diamond Tool, which is practically impossible due to Rapid Tool Wear, is realized by applying elliptical vibration cutting technology which has been developed by the authors. A practical ultrasonic elliptical vibration cutting system is developed in the present research, which consists of a practical vibration control system and an ultraprecision planning machine. The control system is fabricated to keep the elliptical vibration to have a desired locus, where the amplitudes of the two directional vibrations and their phase shift are kept to be desired values, and the vibration frequency is locked to an average value of their resonant frequencies. The vibration control system is mounted on the on the ultraprecision planning machine, which consists of three feed tables with double hydrostatic oil guideways in XYZ axes, two rotary index tables in BC axes and a five axis control system. The developed elliptical vibration cutting system is applied to ultraprecision diamond planning of hardened die steel, and a high quality mirror surface is obtained over a large area of the whole finished surface. Maximum roughness of the finished surface is less than 0.04 /spl mu/m Ry, although the cutting distance reaches 1110 m. On the other hand, the surface finished by ordinary cutting without the vibration, is cloudy with maximum roughness of more than 0.52 /spl mu/m Ry, within a cutting distance of 1 m. Based on this advantage, the elliptical vibration cutting system is successfully applied to ultraprecision micromachining of dies for a front light panel of LCD. An optical quality surface with fine microgrooves over a large area of 122 /spl times/ 91 mm/sup 2/ and with surface roughness of less than 0.04 /spl mu/m Ry is obtained by the developed system, which is difficult for any conventional machining methods including grinding, polishing and ordinary cutting.
Dragos Axinte - One of the best experts on this subject based on the ideXlab platform.
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state of the art of surface integrity in machining of metal matrix composites
International Journal of Machine Tools & Manufacture, 2019Co-Authors: Zhirong Liao, Ali M Abdelhafeez, Yue Yang, Oriol Gavalda Diaz, Dragos AxinteAbstract:Abstract Metal matrix composites (MMCs), as advanced substitutes of monolithic metallic materials, are currently getting an increasing trend of research focus as well as industrial applications for demanding applications such as aerospace, nuclear and automotive because of their enhanced mechanical properties and relative lightweight. Nevertheless, machining of MMC materials remains a challenging task as a result of their structural heterogeneity which leads to deterioration of the machined surface integrity and Rapid Tool Wear. While most of the research was focused on testing and analytical/numerical investigations of the Tool Wear, limited work was focused on machined surface integrity of MMCs. This paper presents a detailed literature survey on the conventional and non-conventional machining of metal matrix composites with the primary focus on the aspects related to workpiece surface integrity. The contribution of material mechanical and microstructural properties as well as the material removal mechanism upon the quality of workpiece surfaces/subsurface are discussed along with their influences on the fatigue performance of machined part.
