缺口滚压强化后残余应力应变分布的数值模拟

NUMERICAL SIMULATION OF DISTRIBUTION OF RESIDUAL STRESS AND STRAIN AFTER ROLLING BENEATH A NOTCH

缺口零件滚压后，由于塑性变形而引起的残余压应力可以大幅度地提高其疲劳性能。研究了用平面应变压入模型来模拟滚压过程的可行性，并通过大变形弹塑性有限元方法，对缺口根部表面以下的残余应力应变分布进行了分析和预测，详细讨论了材料强度、缺口半径ｒ以及压下量△ｈ对残余应力分布的影响。文中的预测结果与实验结果相符合。

The fatigue property of notched part can be improved significantly by introducing compressive residual stress resulting from plastic deformation at the notch,It is investigated whether the rolling process could be simulated by a plane-strain indenting with a model in the paper.The residual stress and strain distributions beneath the notch are analysed and predicted by using finite element method(FEM)of large strain elasto-plastic analysis, The effects of material strength, notch radius r,and indentation depth △h on the distributions of residual stress are discussed.The agreement of predicted and experimental results is good enough.