The Experts below are selected from a list of 31956 Experts worldwide ranked by ideXlab platform
Jianfeng Li - One of the best experts on this subject based on the ideXlab platform.
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three dimensional finite element simulation of Cutting forces and Cutting Temperature in hard milling of aisi h13 steel
Procedia Manufacturing, 2017Co-Authors: Qing Zhang, Song Zhang, Jianfeng LiAbstract:Abstract Compared with the traditional technological process, hard milling of hot work tool steel (AISI H13) can significantly improve the physical/mechanical performances of machined components. A three dimensional (3D) finite element (FE) simulation model was built in this research to investigate the complex nonlinear process. First, the geometric model of workpiece was established considering the previous machined surface profile in actual milling process. Secondly, the prediction validation of the simulation model about hard milling process was verified by comparing the simulated Cutting forces with the experiment results. Finally, the effect of Cutting speed and feed rate on Cutting forces and Cutting Temperature were researched by using the FE simulation model. The results indicate that Cutting forces increase with the increase of feed rate, while Cutting Temperature increases with the increase of Cutting speed. The effects of Cutting speed on Cutting forces and feed rate on Cutting Temperature are not significant. The simulated Temperature is much lower than the austenitizing Temperature of AISI H13 steel which means white layer is unlikely to be formed under the Cutting conditions used in this study. The research can contribute to the fundamental understanding of mechanism and optimization of Cutting parameters in hard milling.
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the effect of Cutting Temperature in milling of carbon fiber reinforced polymer composites
Composites Part A-applied Science and Manufacturing, 2016Co-Authors: Haijin Wang, Dandan Zhang, Jianfeng LiAbstract:Abstract Temperature is a key factor that affects the quality of carbon fiber reinforced polymer (CFRP) Cutting. Degradation of resin will occur within the machined surface or surface layer with the Temperature rise. In this research, the Temperature rise under the condition of line heat source in high-speed movement was analyzed, and it was found that the thermal conductivity in different fiber orientation is a key factor for the rise of Cutting Temperature. Based on the analysis of the thermal conductivity in different fiber orientation, the relationship between Cutting Temperature and fiber orientation was evaluated. Verification experiments were designed to capture the signal of Cutting Temperature using the tool-workpiece thermocouple technique. The influence of Cutting Temperature on machining quality was also studied with scanning electron microscope (SEM). Degradation of resin is occurred within the machined surface or surface layer when the Cutting Temperature exceeds the glass-transition Temperature (Tg).
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evaluation of Cutting force and Cutting Temperature in milling carbon fiber reinforced polymer composites
The International Journal of Advanced Manufacturing Technology, 2016Co-Authors: Haijin Wang, Jianfeng Li, Laixiao Lu, Nan LiAbstract:The Cutting Temperature and Cutting force are some of the main factors that influence the surface quality of carbon fiber-reinforced polymer (CFRP). However, few investigations have been done on Cutting Temperature because it is difficult to capture the dynamic response of the Temperature measurement system. Degradation of resin will occur within the machined surface or surface layer as the Temperature exceeds the glass-transition Temperature of the resin matrix. In this research, the relationship between Cutting parameters and Cutting Temperature, Cutting force were developed by response surface methodology (RSM). The experiments were designed using the tool-workpiece thermocouple technique. Taking into consideration the effect of the glass-transition Temperature, the influence of Cutting force and Cutting Temperature on surface quality of CFRP was analyzed. Analysis results showed that Spindle speed is the key parameter which influenced the Cutting Temperature while feed rate is the key parameter which influenced the Cutting force in milling of CFRP. When the Cutting Temperature exceeds the glass-transition Temperature (Tg), the matrix cannot provide enough support to the fibers, and the machining quality of composite material is poor.
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an experimental investigation of the influence of Cutting parameters on Cutting Temperature in milling ti6al4v by applying semi artificial thermocouple
The International Journal of Advanced Manufacturing Technology, 2014Co-Authors: Jianfeng Li, Qingchun XiongAbstract:An investigation was reported on the Cutting Temperature in milling Ti6Al4V by applying semi-artificial thermocouple. ANOVA was conducted on the experimental results, and regression models were obtained. Analysis results showed that the tool Temperature and workpiece Temperature performed a similar rising trend with the increase of Cutting parameters, including Cutting speed, feed rate, radial feed, and axial feed. And their influence degrees decreased successively. The Cutting force with different Cutting parameters was also measured, and the relationship between Cutting Temperature and Cutting force was discussed. It was found that Cutting Temperature and Cutting force obtained in the experiment had the same fluctuation feature. Therefore, the Cutting force and Cutting Temperature could complement each other for monitoring and analysis of the Cutting process.
Kornel F. Ehmann - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of hard turning mechanisms by pcbn tooling embedded micro thin film thermocouples
Journal of Manufacturing Science and Engineering-transactions of The Asme, 2013Co-Authors: Kornel F. EhmannAbstract:Temperature-distribution measurements in Cutting tools during the machining process are extremely difficult and remain an unresolved problem. In this paper, Cutting Temperature distributions were measured by thin film thermocouples (TFTCs) embedded into polycrystalline cubic boron nitride (PCBN) Cutting inserts in the immediate vicinity of the tool-chip interface. The embedded TFTC array provides Temperature measurements with a degree of spatial resolution (100 μm) and dynamic response (150 ns) that is not possible with currently employed methods due to the micro-scale junction size of the TFTCs. Using these measurements during hard turning, steady-state, dynamic, as well as chip morphology and formation process analyses were performed based on the Cutting Temperature and Cutting force variations in the Cutting zone. It has been shown that the Temperature changes in the Cutting zone depend on the shearing band location in the chip and the thermal transfer rate from the heat generation zone to the Cutting tool. Furthermore, it became evident that the material flow stress and the shearing bands greatly affect not only the chip formation morphology but also the Cutting Temperature field distributions in the Cutting zone of the Cutting insert.
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A thermo-mechanical model of dry orthogonal Cutting and its experimental validation through embedded micro-scale thin film thermocouple arrays in PCBN tooling
International Journal of Machine Tools and Manufacture, 2013Co-Authors: Kornel F. EhmannAbstract:Abstract Cutting Temperature and its distribution in the Cutting zone are a critical factor that significantly affects tool life and degrades part accuracy during metal removal operations. However, issues surrounding their modeling and experimental validation in the immediate Cutting zone still remain an unresolved issue. A major impediment is the unavailability of adequate Temperature measurement methods with sufficient temporal and spatial resolution to measure actual Temperatures and validate predictive models. In this paper, a model for the dry orthogonal Cutting process with thermo-mechanical coupling effects, i.e., interactions between the stress state, strain rates and the Temperature softening of material in the plastic deformation zone, is proposed to predict Cutting Temperature distribution in the Cutting zone. The feasibility and prediction accuracy of the model is verified by experimental measurements through Thin Film Thermocouple (TFTC) arrays embedded at the immediate vicinity of the Cutting zone into Polycrystalline Cubic Boron Nitride (PCBN) tooling. The experimental verification is performed under hard turning conditions. It has been shown that the predictions of the proposed model are in very close agreement with the experimentally measured results including the Cutting forces, chip thickness and Cutting Temperature distributions on the rake and flank faces in the Cutting zone. Furthermore, the modeling results have also provided an essential understanding on the stress distributions at the tool/chip and work/tool interfaces as well as of the nature of the chip flow velocity along the rake face of the Cutting tool.
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experimental investigation of hard turning mechanisms by pcbn tooling embedded micro thin film thermocouples
ASME 2012 International Manufacturing Science and Engineering Conference collocated with the 40th North American Manufacturing Research Conference and, 2012Co-Authors: Kornel F. EhmannAbstract:Temperature-distribution measurements in Cutting tools during the machining process are extremely difficult and remain an unresolved problem. In this paper, Cutting Temperature distributions are measured by thin film thermocouples (TFTCs) embedded into Polycrystalline Cubic Boron Nitride (PCBN) Cutting inserts in the immediate vicinity of the tool-chip interface. Using these measurements, steady and dynamic phenomena during hard turning as well as the chip morphology and formation process were analyzed based on the Cutting Temperature distributions in the insert. The relationship between the Cutting Temperature-field distributions in the PCBN insert and the segmented chip formation is analyzed using Temperature-distribution mapping. It is shown that the Temperature-distribution in the Cutting zone depends on the shearing band distribution in the chip and the thermal transfer rate from the heat generation zone to the Cutting tool. Furthermore, it became evident that the material flow stress and the shearing bands greatly affect not only the chip formation morphology but also the Cutting Temperature field distributions in the Cutting zone of the Cutting insert.Copyright © 2012 by ASME
Nikhil Ranjan Dhar - One of the best experts on this subject based on the ideXlab platform.
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optimization of surface roughness and Cutting Temperature in high pressure coolant assisted hard turning using taguchi method
The International Journal of Advanced Manufacturing Technology, 2017Co-Authors: Nikhil Ranjan DharAbstract:In this article, the effects of material hardness and high-pressure coolant jet over dry machining are evaluated in respect of surface roughness and Cutting Temperature using Taguchi L36 orthogonal array. The experimental data was analyzed using empirical cumulative distribution function and box plot with respect to material hardness and machining environment. Afterward, optimization of the quality responses is performed using signal-to-noise ratio. As part of Taguchi optimization, the “smaller is better” was adopted as optimization principle; the design of experiment was used for parameters orientation, and the analysis of variance was used for determining the effects of control factors. For the present experimental studies, three types of hardened steels (40 HRC, 48 HRC, and 56 HRC) were turned by coated carbide insert at industrial speed–feed combinations under both dry and high-pressure coolant jet. Depth of cut, being a less significant parameter, was kept fixed. The high-pressure coolant jet was found successful in reducing Cutting Temperature, surface roughness, and tool wear. The statistical analysis showed that work material hardness is the most significant factor for both Cutting Temperature and surface roughness. However, for surface roughness, other variables exerted somewhat similar contribution, while in determining the Cutting Temperature, the environment demonstrated crucial role. The confirmation tests showed 15.85 and 0.28 % error in predicting surface roughness and Cutting Temperature, respectively.
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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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an experimental investigation on effect of minimum quantity lubrication in machining aisi 1040 steel
International Journal of Machine Tools & Manufacture, 2007Co-Authors: Nikhil Ranjan Dhar, Md Tanveer Ahmed, Sumaiya IslamAbstract:Abstract The growing demands for high productivity of machining need use of high Cutting velocity and feed rate. Such machining inherently produces high Cutting Temperature, which not only reduces tool life but also impairs the product quality. Application of Cutting fluids changes the performance of machining operations because of their lubrication, cooling, and chip flushing functions. But the conventional Cutting fluids are not that effective in such high production machining, particularly in continuous Cutting of materials likes steels. Minimum quantity lubrication (MQL) presents itself as a viable alternative for turning with respect to tool wear, heat dissipation, and machined surface quality. This study compares the mechanical performance of MQL to completely dry lubrication for the turning of AISI-1040 steel based on experimental measurement of Cutting Temperature, chip reduction coefficient, Cutting forces, tool wears, surface finish, and dimensional deviation. Results indicated that the use of near dry lubrication leads to lower Cutting Temperature and Cutting force, favorable chip–tool interaction, reduced tool wears, surface roughness, and dimensional deviation.
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the influence of minimum quantity of lubrication mql on Cutting Temperature chip and dimensional accuracy in turning aisi 1040 steel
Journal of Materials Processing Technology, 2006Co-Authors: Nikhil Ranjan Dhar, Sumaiya Islam, M. W. Islam, M A H MithuAbstract:Abstract In metal industries, the use of Cutting fluid has become more problematic in terms of both employee health and environmental pollution. But the use of Cutting fluid generally causes economy of tools and it becomes easier to keep tight tolerances and to maintain workpiece surface properties without damages. Because of them some alternatives has been sought to minimize or even avoid the use of Cutting fluid in machining operations. Some of these alternatives are dry machining and machining with minimum quantity of lubrication (MQL). This paper deals with experimental investigations in the role of MQL on Cutting Temperature, chip formation and product quality in turning AISI-1040 steel at different industrial speed-feed combinations by uncoated carbide insert. The results have been compared with dry machining and machining with soluble oil as coolant. The experimental results indicate that such MQL enables substantial reduction in the Cutting Temperature, dimensional inaccuracy depending upon the levels of the Cutting velocity and feed rate. It was also noted that the chip formation and chip–tool interaction become more favorable under MQL condition. Therefore, it appears that MQL, if properly employed, not only provides environment friendliness but can also improve the machinability characteristics.
Michael F Moran - One of the best experts on this subject based on the ideXlab platform.
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comprehensive proteome analysis of fresh frozen and optimal Cutting Temperature oct embedded primary non small cell lung carcinoma by lc ms ms
Methods, 2015Co-Authors: Wen Zhang, Shingo Sakashita, Paul J Taylor, Mingsound Tsao, Michael F MoranAbstract:Clinical tissue samples provide valuable information for understanding human diseases. One major type of clinical tissue sample that is amenable to various kinds of analysis is fresh frozen and optimal Cutting Temperature (OCT)-embedded primary patient tissue. Recent advances in mass spectrometry (MS) technologies have been widely applied to study human proteomes by using clinical specimens. However, polymeric compounds such as OCT can interfere with MS analyses. Here we present methods that enable the preparation and analysis of fresh frozen and OCT embedded primary tissue samples by LC-MS/MS. A scraping method was first introduced to reduce the heterogeneity of OCT-embedded non-small cell lung carcinoma tumor sections. OCT compound was reproducibly removed by a series of washing steps involving ethanol and water prior to trypsin digestion. In data-dependent acquisition mode, optimized dynamic exclusion duration settings were established to maximize peptide identifications. These sample preparation conditions and MS parameter settings should be utilized or carefully adjusted in order to achieve optimal comprehensive proteome characterization starting from fresh frozen and OCT embedded clinical tissue specimens.
Haijin Wang - One of the best experts on this subject based on the ideXlab platform.
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the effect of Cutting Temperature in milling of carbon fiber reinforced polymer composites
Composites Part A-applied Science and Manufacturing, 2016Co-Authors: Haijin Wang, Dandan Zhang, Jianfeng LiAbstract:Abstract Temperature is a key factor that affects the quality of carbon fiber reinforced polymer (CFRP) Cutting. Degradation of resin will occur within the machined surface or surface layer with the Temperature rise. In this research, the Temperature rise under the condition of line heat source in high-speed movement was analyzed, and it was found that the thermal conductivity in different fiber orientation is a key factor for the rise of Cutting Temperature. Based on the analysis of the thermal conductivity in different fiber orientation, the relationship between Cutting Temperature and fiber orientation was evaluated. Verification experiments were designed to capture the signal of Cutting Temperature using the tool-workpiece thermocouple technique. The influence of Cutting Temperature on machining quality was also studied with scanning electron microscope (SEM). Degradation of resin is occurred within the machined surface or surface layer when the Cutting Temperature exceeds the glass-transition Temperature (Tg).
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evaluation of Cutting force and Cutting Temperature in milling carbon fiber reinforced polymer composites
The International Journal of Advanced Manufacturing Technology, 2016Co-Authors: Haijin Wang, Jianfeng Li, Laixiao Lu, Nan LiAbstract:The Cutting Temperature and Cutting force are some of the main factors that influence the surface quality of carbon fiber-reinforced polymer (CFRP). However, few investigations have been done on Cutting Temperature because it is difficult to capture the dynamic response of the Temperature measurement system. Degradation of resin will occur within the machined surface or surface layer as the Temperature exceeds the glass-transition Temperature of the resin matrix. In this research, the relationship between Cutting parameters and Cutting Temperature, Cutting force were developed by response surface methodology (RSM). The experiments were designed using the tool-workpiece thermocouple technique. Taking into consideration the effect of the glass-transition Temperature, the influence of Cutting force and Cutting Temperature on surface quality of CFRP was analyzed. Analysis results showed that Spindle speed is the key parameter which influenced the Cutting Temperature while feed rate is the key parameter which influenced the Cutting force in milling of CFRP. When the Cutting Temperature exceeds the glass-transition Temperature (Tg), the matrix cannot provide enough support to the fibers, and the machining quality of composite material is poor.
