【摘要】 目的探究二次喷丸工艺参数对42CrMo钢零件表面完整性的影响规律。方法建立三维随机喷丸有限元模型,并通过实验验证有限元模型预测残余应力的准确性。将一次喷丸后零件的表面形貌和应力应变结果作为初始状态导入到二次喷丸模型中,构建出二次喷丸预测模型。分析二次喷丸参数对42CrMo钢零件表面残余应力场、表面粗糙度以及等效塑性形变场的影响情况。结果二次喷丸后,42CrMo钢零件近表层(0～100μm)的残余压应力值均比初始状态有所增加。增加二次喷丸覆盖率对表面残余应力的提升作用最为明显,最大可比初始状态提高63.3%,而增加二次喷丸直径对残余应力的改善效果最不明显。过度增加二次喷丸速度会导致表面粗糙度明显增加,提高二次喷丸覆盖率可显著降低表面粗糙度,覆盖率为300%时,粗糙度比初始状态减小了14.4%。表层PEEQ值随着二次喷丸速度、弹丸直径和覆盖率的增加而增加,但当二次喷丸速度、弹丸直径和覆盖率增加到一定程度后,表层PEEQ值会趋于饱和。结论二次喷丸预测模型揭示了二次喷丸参数与42CrMo钢零件表面完整性之间的影响规律,为二次喷丸的工业应用提供了一定的参考意义。更多还原

【Abstract】 The work aims to explore the influence of dual shot peening parameters on the surface integrity of 42 CrMo steel components. A 3 D random shot peening(SP) finite element model(FEM) was established and the accuracy of predicting the residual stress by the model was verified by experimental data. The surface topography and stress-strain results of the component after single shot peening were imported into the dual shot peening model as the initial state, to construct the prediction model of dual shot peening. The effects of the dual shot peening parameters on the surface residual stress field, surface roughness and equivalent plastic deformation(PEEQ) field of 42 CrMo steel components were analyzed. The compressive residual stress value near the surface layer(0～100 μm) of 42 CrMo steel components after dual shot peening increased compared with the initial state, and the dual shot peening coverage ratio had the most obvious effect on the improvement of the surface residual stress, with the maximum increase of 63.3% compared with the initial state. On the contrary, the improvement effect of dual shot peening diameter on residual stress was the least obvious. The excessive increase of the dual shot peening speed would lead to the significant increase of the surface roughness while the increase of the dual shot peening coverage ratio could significantly reduce the surface roughness, and the roughness was 14.4% less than the initial state when the coverage ratio was 300%. The surface PEEQ value ascended with the increase of the dual shot peening speed, shot diameter and coverage ratio. However, when the shot speed, shot diameter and coverage ratio increased to a certain extent, the PEEQ value tended to be saturated. The prediction model of dual shot peening reveals the relationship between dual shot peening parameters and surface integrity of 42 CrMo steel component, which provides some guidance for the industrial application of dual shot peening.更多还原