Particle-tool interactions,which govern the synergetic deformation of SiC particle reinforced Al matrix composites under mechanical machining,strongly depend on the geometry of particle position residing on cutting pa...Particle-tool interactions,which govern the synergetic deformation of SiC particle reinforced Al matrix composites under mechanical machining,strongly depend on the geometry of particle position residing on cutting path.In the present work,we investigate the influence of cutting path on the machinability of a SiCp/Al composite in multi-step ultra-precision diamond cutting by combining finite element simulations with experimental observations and characterization.Be consistent with experimentally characterized microstructures,the simulated SiCp/Al composite is considered to be composed of randomly distributed polygonally-shaped SiC particles with a volume fraction of 25 vol%.A multi-step cutting strategy with depths of cut ranging from 2 to 10 lm is adopted to achieve an ultimate depth of cut of 10 lm.Intrinsic material parameters and extrinsic cutting conditions utilized in finite element simulations of SiCp/Al cutting are consistent with those used in corresponding experiments.Simulation results reveal different particle-tool interactions and failure modes of SiC particles,as well as their correlations with machining force evolution,residual stress distribution and machined surface topography.A detailed comparison between numerical simulation results and experimental data of multi-step diamond cutting of SiCp/Al composite reveals a substantial impact of the number of cutting steps on particle-tool interactions and machined surface quality.These findings provide guidelines for achieving high surface finish of SiCp/Al composites by ultra-precision diamond cutting.展开更多
Based on the principles of differential geometry,the basic equations are derived for generating gouging free tool path in 5-axis NC face milling,the influence of surface's local geometry is discussed,and the condi...Based on the principles of differential geometry,the basic equations are derived for generating gouging free tool path in 5-axis NC face milling,the influence of surface's local geometry is discussed,and the conditions of using cutter with reasonable diameter are presented.展开更多
A deduced cutting force prediction model for circular end milling process is presented in this paper. Traditional researches on cutting force model usually focus on linear milling process which does not meet other cut...A deduced cutting force prediction model for circular end milling process is presented in this paper. Traditional researches on cutting force model usually focus on linear milling process which does not meet other cutting conditions, especially for circular milling process. This paper presents an improved cutting force model for circular end milling process based on the typical linear milling force model. The curvature effects of tool path on chip thickness as well as entry and exit angles are analyzed, and the cutting force model of linear milling process is then corrected to fit circular end milling processes. Instantaneous cutting forces during circular end milling process are predicted according to the proposed model. The deduced cutting force model can be used for both linear and circular end milling processes. Finally, circular end milling experiments with constant and variable radial depth were carried out to verify the availability of the proposed method. Experiment results show that measured results and simulated results corresponds well with each other.展开更多
基金supports from the National Natural Science Foundation of China(NSFC)-German Research Foundation(DFG)International Joint Research Programme(51761135106)the Open Research Foundation of State Key Laboratory of Digital Manufacturing Equipment and Technology in Huazhong University of Science and Technology,China(DMETKF2019016)+1 种基金the Shandong Key R&D Program(2019GGX104027)the Fundamental Research Funds for the Central Universities。
文摘Particle-tool interactions,which govern the synergetic deformation of SiC particle reinforced Al matrix composites under mechanical machining,strongly depend on the geometry of particle position residing on cutting path.In the present work,we investigate the influence of cutting path on the machinability of a SiCp/Al composite in multi-step ultra-precision diamond cutting by combining finite element simulations with experimental observations and characterization.Be consistent with experimentally characterized microstructures,the simulated SiCp/Al composite is considered to be composed of randomly distributed polygonally-shaped SiC particles with a volume fraction of 25 vol%.A multi-step cutting strategy with depths of cut ranging from 2 to 10 lm is adopted to achieve an ultimate depth of cut of 10 lm.Intrinsic material parameters and extrinsic cutting conditions utilized in finite element simulations of SiCp/Al cutting are consistent with those used in corresponding experiments.Simulation results reveal different particle-tool interactions and failure modes of SiC particles,as well as their correlations with machining force evolution,residual stress distribution and machined surface topography.A detailed comparison between numerical simulation results and experimental data of multi-step diamond cutting of SiCp/Al composite reveals a substantial impact of the number of cutting steps on particle-tool interactions and machined surface quality.These findings provide guidelines for achieving high surface finish of SiCp/Al composites by ultra-precision diamond cutting.
文摘Based on the principles of differential geometry,the basic equations are derived for generating gouging free tool path in 5-axis NC face milling,the influence of surface's local geometry is discussed,and the conditions of using cutter with reasonable diameter are presented.
基金co-supported by Open National Natural Science Foundation of China(No.51005183)National Science and Technology Major Project(No.2011ZX04016031)China Postdoctoral Science Foundation(No.2012M521804)
文摘A deduced cutting force prediction model for circular end milling process is presented in this paper. Traditional researches on cutting force model usually focus on linear milling process which does not meet other cutting conditions, especially for circular milling process. This paper presents an improved cutting force model for circular end milling process based on the typical linear milling force model. The curvature effects of tool path on chip thickness as well as entry and exit angles are analyzed, and the cutting force model of linear milling process is then corrected to fit circular end milling processes. Instantaneous cutting forces during circular end milling process are predicted according to the proposed model. The deduced cutting force model can be used for both linear and circular end milling processes. Finally, circular end milling experiments with constant and variable radial depth were carried out to verify the availability of the proposed method. Experiment results show that measured results and simulated results corresponds well with each other.