喷丸残余应力场有限元数值模拟分析

Numerical Simulation and Analysis of Residual Stress of Shot Peening by Finite Element Method

为探讨喷丸参数对残余应力大小及分布的影响,利用LS-DYNA软件建立了分批顺序撞击的9丸粒有限元模型,对喷丸残余应力场进行了数值仿真研究,并与已有结果进行对比以验证其准确性。在此基础上研究了弹丸速度、重复打击次数、搭接率以及多丸粒分布对残余压应力的影响。结果表明:增加弹丸搭接率和覆盖率可使各点的残余应力分布趋于一致;重复打击一定次数后将使残余应力增长率减缓并最终趋于饱和;最大残余压应力及其到达深度均随喷丸速度增加而增大。本模型为获得理想残余应力提供了理论依据。

A9-shot model of finite element method was established based on LS-DYNA software to simulate the residual stress induced by shot peening,thereby exploring the effects of related shot peening parameters on residual stress and its distribution.The analytical results obtained with the as-established model were compared with those of previous ones so as to verify the model.Furthermore,the effects of velocity,number of repeated impacts,lap rate and distribution of multiple shots on residual compressive stress were discussed.It was found that the residual stress of each point tended to be unanimous with the increase of the lap rate and coverage rate.After a certain number of repeated impacts,the growth rate of the residual stress decreased and tended to be saturated finally,and the maximum residual stress and its depth increased as the velocity increased.The present research,hopefully,is to help provide theoretical basis for achieving ideal residual stress.