基于多丸粒模型的喷丸表面强化过程数值模拟

针对喷丸表面强化过程,利用有限元法,建立了均匀分布的多丸粒喷丸强化数值模型,研究了喷丸速度、连续冲击及二次冲击弹丸速度对于目标靶体内残余应力场的影响;利用多丸粒偏置建模法,建立不同覆盖率的多丸粒仿真模型,研究喷丸覆盖率、连续冲击对于残余应力场的影响,对比了两种多丸粒喷丸模型。结果表明,提高喷丸速度可增加残余压应力层深度,但对残余应力最大幅值没有显著影响;连续冲击引起残余应力的饱和,残余应力分布没有明显变化;后续冲击弹丸的速度对于残余应力场有明显的影响;偏置高覆盖率喷丸强化模型可获得较均匀分布的残余应力场,压应力最大幅值与喷丸覆盖率及作用区域有关。

Numerical simulation of shot-peening process based on multiple shot model

This investigation was devoted to the modeling and simulation of the residual stress field resulting from the shot-peening process using multiple-shot model.The regular multiple-shot model was established and the effects of peening velocity and successive impact were investigated.Moreover,the effect of the second shot impact velocity on the residual stress field induced by the first impact was studied.Different multiple-shot impact models were established by overlapping model method with high peening coverage.The analysis results indicated that the increase of peening velocity improved the affected depth of compressive residual stress,but had little effect on the maximum residual stress.The successive impacts caused no significant change of the residual stress distribution and the depth of compressive stress zone.The subsequent shot impact velocity had the significant effect on the residual stress distribution of the target plate induced by the previous shot impacts.A uniform residual stress distribution was achieved with the increase of the peening coverage and the maximum compressive residual stress was related to the peening coverage and impact region.