Study on the Influence of Temperature on the Surface Asperity in Micro Cross Wedge Rolling
When the common deformation processes are scaled down to micro/meso dimensions,size effect is the particular phenomena in microforming,which is related to the dominant influence of single grains inside the micropart.The conventional cross wedge rolling (CWR) is introduced into the micro scale in order to take the advantages of CWR.The micro cross wedge rolling (MCWR) has to confront with the phenomena of size effect that occurs in the common microforming processes inevitably.One of the approaches to compensate size effect is to increase the deforming temperature.An increased formability is achieved because more slip systems of polycrystal metal are activated at the elevated temperature.This reduces the anisotropic material behavior resulting in a more homogeneous forming with improved reproducibility.In this study,a YAG laser beam is applied to heat the workpiece.Finite element model (FEM) associated with a material constitutive formulation considering dislocation mechanics is set up to simulate the MCWR of pure copper utilizing the laser heating.The surface asperity as an indication of material heterogeneity in micro scale is quantitatively analysed.The simulation results show a good agreement with experimental results in terms of the surface asperity.
Microforming Size Effect Surface Asperity Finite Element Method
H.N.Lu D.B.Wei Z.Y.Jiang D.Wu X.M.Zhao
School of Mechanical Materials and Mechatronic Engineering,University of Wollongong,Wollongong,Austr State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang,China
国际会议
沈阳
英文
1032-1037
2013-07-06（万方平台首次上网日期，不代表论文的发表时间）