42CrMo钢精车加工表面残余应力有限元仿真研究

Finite element simulation study on surface residual stress of 42CrMo steel in finish turning

基于ABAQUS软件建立了42CrMo锻钢活塞外圆精车加工的二维切削仿真模型,采用单因素法研究了切削参数对残余应力的影响规律。结果表明:42CrMo钢精车加工过程中,热应力引起的残余拉应力起主导作用,已加工表面产生残余拉应力并沿深度方向迅速转变为压应力。残余应力层深度随进给量和背吃刀量的增大而增大,切削速度对残余应力层深度影响不显著。表面残余拉应力随切削速度和进给量的增大而增大,背吃刀量对表面残余应力影响不显著。最大残余拉应力出现在工件已加工表面以下,表面残余应力、最大残余拉应力和最大残余压应力随切削参数的变化趋势与切削温度随切削参数的变化趋势基本一致。

Based on ABAQUS software,a two-dimensional cutting simulation model of 42CrMo forged steel piston finish turning was established,and the single-factor method was used to study the influence law of cutting parameters on residual stress.The results show that the residual tensile stress caused by thermal stress plays a leading role in the finish turning process of 42CrMo steel.The residual tensile stress is generated on the processed surface and rapidly changes into compressive stress along the depth direction.The depth of the residual stress layer increases with the increase of the feed rate and the cutting depth,and the cutting speed has no significant effect on the depth of the residual stress layer.The surface residual tensile stress increases with the increase of the cutting speed and the feed rate,and the effect of cutting depth on surface residual stress is not significant.The maximum residual tensile stress appears below the processed surface of the workpiece.The change trend of the surface residual stress,maximum residual tensile stress and maximum residual compressive stress with cutting parameters is basically consistent with the change trend of cutting temperature with cutting parameters.