The Experts below are selected from a list of 22680 Experts worldwide ranked by ideXlab platform
Zhengyang Xu - One of the best experts on this subject based on the ideXlab platform.
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effect of tube electrode inner structure on Machining Performance in tube electrode high speed electrochemical discharge drilling
Journal of Materials Processing Technology, 2016Co-Authors: Yan Zhang, Zhengyang XuAbstract:Abstract Film cooling holes are required in many crucial and widely used structures. The creation of good film cooling holes requires Machining at high speeds with high accuracy and good surface quality. For this purpose, a promising hybrid Machining method combining electrical discharge Machining and electrochemical Machining, called tube-electrode high-speed electrochemical discharge drilling (TEHECDD), has been proposed, which can be used for Machining difficult-to-machine superalloys. In TEHECDD, the flushing condition is considered as an important element. To improve the flushing condition and further enhance the Machining Performance, improved tube-electrode structures, obtained by varying the inner diameter and inner shape, are introduced. In this study, different inner structures are designed for the tube electrodes, whereby the mechanism of the enhanced TEHECDD Performance for different tube-electrode inner shapes are analysed and the effects of different tube-electrode inner structures on the Machining Performance are investigated. The results show that an increase in the tube-electrode inner diameter results in a higher material removal rate, smaller average bore diameter, and smaller taper angle. However, for the single-hole tube electrode, a larger inner hole results in the formation of a residual cylinder. Thus, the double-hole and multi-hole tube electrodes are proposed and found to be effective in removing the residual cylinder. Finally, it is verified that the tube electrodes with improved inner shapes can be used to further enhance the Machining Performance. The double-hole tube electrode is confirmed to have the optimal structure.
I S Jawahir - One of the best experts on this subject based on the ideXlab platform.
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the effect of active phase of the work material on Machining Performance of a niti shape memory alloy
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2015Co-Authors: Yusuf Kaynak, H E Karaca, Ronald D Noebe, I S JawahirAbstract:Poor machinability with conventional Machining processes is a major shortcoming that limits the manufacture of NiTi components. To better understand the effects of phase state on the Machining Performance of NiTi alloys, cutting temperature, tool-wear behavior, cutting force components, tool-chip contact length, chip thickness, and machined surface quality data were generated from a NiTi alloy using precooled cryogenic, dry, minimum quantity lubrication (MQL), and preheated Machining conditions. Findings reveal that Machining NiTi in the martensite phase, which was achieved through precooled cryogenic Machining, profoundly improved the Machining Performance by reducing cutting force components, notch wear, and surface roughness. Machining in the austenite state, achieved through preheating, did not provide any benefit over dry and MQL Machining, and these processes were, in general, inferior to cryogenic Machining in terms of Machining Performance, particularly at higher cutting speeds.
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Contour finish turning operations with coated grooved tools : Optimization of Machining Performance
Journal of Materials Processing Technology, 2009Co-Authors: Masaya Hagiwara, S. Chen, I S JawahirAbstract:This paper presents a new methodology for optimization of Machining Performance in contour finish turning operations. Two Machining Performance measures, chip breakability and surface roughness, are considered as optimization criteria due to their importance in finishing operations. Chip breakability covers two major factors: chip shape and size. Comprehensive case studies are presented to demonstrate the determination and application of optimal cutting conditions through experimental validation.
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an investigation of sustained Machining Performance for controlled surface quality requirements in porous tungsten
IEEE Transactions on Electron Devices, 2005Co-Authors: Shi Chen, D Head, M Effgen, I S JawahirAbstract:The work presented in this paper focuses on sustaining Machining Performance in face contour turning of porous tungsten for controlled surface quality requirements. A study of the combined effects of tool geometry (i.e., cutting edge radius, tool nose radius, clearance angle, included angle, etc.), tool material (carbide and diamond tool inserts), work material properties, and Machining conditions (cutting speed, depth of cut, and feed) on the porosity in the face-contour turning of porous tungsten was undertaken. Correlations are shown between the cutting edge radius and the cutting forces which progressively increase in continuous cutting as a result of progressive tool-wear. This research establishes the possibility of developing a base of knowledge from which an analytical model can be produced to predict smearing on the machined surface.
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Towards integration of hybrid models for optimized Machining Performance in intelligent manufacturing systems
Journal of Materials Processing Technology, 2003Co-Authors: I S Jawahir, A.k. Balaji, K.e. Rouch, John R. BakerAbstract:Abstract This paper discusses integration issues involved in comprehensive evaluation of optimized Machining Performance for intelligent manufacturing systems . Machining Performance is evaluated by major measures such as cutting forces/power/torque, tool-wear/tool-life, chip-form/chip breakability, surface roughness/surface integrity and part accuracy. The Machining Performance is discussed from a systems framework comprising three primary elements that constitute a Machining system; the machine tool , cutting tool and work material . Hybrid methodologies, comprising suitable blends of different modeling techniques are emphasized in this paper. These models can be supplemented by sensory data which defines the unique characteristics of a specific Machining system. The modeling of Machining Performance using traditional techniques, hybrid methodologies and sensor-based information is followed by optimization methods to obtain the optimized Machining Performance for the specific Machining system. The presented methodology provides an effective means for developing intelligent , integrated models and optimization modules within modern machine tools to enable instantaneous assessment of Machining Performance with suitable on-line process and control strategies.
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PREDICTIVE MODELING OF Machining Performance IN TURNING OPERATIONS
Machining Science and Technology, 1998Co-Authors: I S Jawahir, Oscar W. Dillon, A. K. Balajj, M. Redetzky, N. FangAbstract:ABSTRACT Recent definitions of Machining Performance have been based on technological Machining Performance measures such as cutting forces, tool-life/tool-wear, chip-form/chip breakability, surface roughness, etc. However, modeling work on these Performance measures has so far been characterized by isolated treatment of each of these measures. The modeling approach followed by the Machining research group at the University of Kentucky aims for an integrated predictive modeling methodology for the major technological Machining Performance measures. Extensive use of analytical, experimental, numerical, and Al-based approaches is made in the development of these predictive models. This paper presents the outline of this modeling effort and reports the progress made to date in implementing it.
Chuanzhen Huang - One of the best experts on this subject based on the ideXlab platform.
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mechanisms of enhancing the Machining Performance in micro abrasive waterjet drilling of hard and brittle materials by vibration assistance
International Journal of Machine Tools & Manufacture, 2020Co-Authors: Thai Nguyen, Jun Wang, Chuanzhen HuangAbstract:Abstract A study of the effect of vibration assistance on the Machining Performance in the micro slurry jet drilling of hard and brittle materials typified by single crystal 4H-SiC wafers is presented. It shows that this technology provides benefits to the Machining process by improving both material removal rate and surface finish, and such improvements are more profound by increasing the vibration amplitude. Ductile-like mode deformation is noticed to be dominant on the surfaces processed with vibration assistance for this highly brittle material. It is found that major material removal is achieved through brittle fractures of the material by the direct impact of the jet. A smoothening process following the jet impact through a crossflow-driven motion of the particles over the brittle-fractured surface at an engaging depth below the critical value for the cleavage fracture of the material improves the processed surface quality. A finite element (FE) analysis of the particle impact reveals that the vibration applied to the target surface adds no energy to the impacting process, but makes the transfer and application of jet energy more effective by promoting a sweeping effect. This effect clears the surface from the accumulation of the after-impact particles, allowing the subsequent particles from the jet to impact directly onto the surface. The FE study also shows that the applied vibration does not change the engaging depth made by the after-impact particles, but raises the crossflow velocity through the sweeping effect. This enables the smoothening process to extend beyond the restriction imposed by a repeating action of dull particles, and results in the brittle-fractured surface to be flattened and smoothened.
Yan Zhang - One of the best experts on this subject based on the ideXlab platform.
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effect of tube electrode inner structure on Machining Performance in tube electrode high speed electrochemical discharge drilling
Journal of Materials Processing Technology, 2016Co-Authors: Yan Zhang, Zhengyang XuAbstract:Abstract Film cooling holes are required in many crucial and widely used structures. The creation of good film cooling holes requires Machining at high speeds with high accuracy and good surface quality. For this purpose, a promising hybrid Machining method combining electrical discharge Machining and electrochemical Machining, called tube-electrode high-speed electrochemical discharge drilling (TEHECDD), has been proposed, which can be used for Machining difficult-to-machine superalloys. In TEHECDD, the flushing condition is considered as an important element. To improve the flushing condition and further enhance the Machining Performance, improved tube-electrode structures, obtained by varying the inner diameter and inner shape, are introduced. In this study, different inner structures are designed for the tube electrodes, whereby the mechanism of the enhanced TEHECDD Performance for different tube-electrode inner shapes are analysed and the effects of different tube-electrode inner structures on the Machining Performance are investigated. The results show that an increase in the tube-electrode inner diameter results in a higher material removal rate, smaller average bore diameter, and smaller taper angle. However, for the single-hole tube electrode, a larger inner hole results in the formation of a residual cylinder. Thus, the double-hole and multi-hole tube electrodes are proposed and found to be effective in removing the residual cylinder. Finally, it is verified that the tube electrodes with improved inner shapes can be used to further enhance the Machining Performance. The double-hole tube electrode is confirmed to have the optimal structure.
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.
