铸造残余应力对铝合金副车架疲劳寿命的影响

运用ProCast软件对真空压铸铝合金副车架进行铸造工艺仿真,得到副车架的残余应力场.通过中间文件把残余应力作为初始条件加载到副车架力学分析有限元模型上,利用HyperMesh、ABAQUS、Fe-Safe等软件对副车架进行疲劳寿命分析.结果显示残余应力使纵向工况、侧向工况、垂向工况中的疲劳寿命分别降低了48%、71.3%、32.5%.对副车架进行台架试验,结果表明:考虑了残余应力的疲劳仿真结果更接近台架试验结果,并且该铝合金副车架的性能指标符合实际使用要求.因此考虑了残余应力的疲劳仿真对真空压铸铝合金副车架的生产更具指导意义.

Effect of Casting Residual Stress on Fatigue Life of Aluminum Alloy Sub-frame

The residual stress field of aluminum alloy sub-frame was obtained through its casting process simulation by the software ProCast. Then, the residual stresses were loaded into the finite element model of aluminum alloy sub-frame for the mechanical analysis through the intermediate files as the initial condition. The fatigue life of the sub-frame was analyzed by using HyperMesh,ABAQUS,Fe-Safe and so on.The results showed that the residual stress decreased the working life in the longitudinal, lateral and vertical conditions by 48%, 71.3% and 32.5%, respectively.A bench test on the sub-frame was also performed. The results showed that the fatigue simulation results of residual stress were closer to the results of the bench test, and the performance index of the aluminum sub-frame satisfied the practical requirements.Therefore, the fatigue simulation considering the residual stress provides significance for the vacuum die casting aluminum alloy sub-frame production.