铝合金预拉伸板残余应力数值模拟方法研究

Study on Numerical Simulation Method of Residual Stress of Aluminum Alloy Pre-Stretching Board Based on Change of Material Parameters

针对铝合金预拉伸板残余应力仿真结果误差较大的问题,提出一种考虑铝合金材料参数变化的数值模拟方法。铝合金预拉伸板淬火和拉伸过程中屈服强度和弹性模量的变化考虑进来,其中屈服强度的变化通过设置温度阈值实现,弹性模量的变化通过将每个单元积分点弹性模量表示成温度和塑性变形的函数来实现。通过验证发现,上述方法有效地降低了仿真结果与实验数据之间的误差,能很好地预测铝合金板残余应力的大小和变化趋势。通过对照仿真发现淬火与拉伸工艺之间的自然时效时间越长,所提方法的效果越显著。

Aiming at the problem of large error of in the simulation results of residual stress of simulation results of aluminum alloy pre-stretching board,a numerical simulation method considering the change of aluminum alloy material parameters is proposed.When establishing the simulation model,the changes of yield strength and elastic modulus during quenching and stretching of aluminum alloy pre-stretching board were are taken into account.The change of yield strength wais realized by setting the temperature threshold,and the change of elastic modulus wais realized by expressing the elastic modulus of each element integral point as a function of temperature and plastic deformation.Through The verification shows,it is found that this method can effectively reduce the error between the simulation results and the experimental data,thusand can well predict the magnitude and change trend of residual stress in aluminum alloy plate.Throughrough the comparative simulation experiment,it is found,it is found that the longer the natural aging time between quenching and drawing process,the more significant the effect of this method is.