收口工艺对螺母表面残余应力分布的影响

Influence of necking process on residual stress distribution of nut surface

为控制螺母表面残余应力值以防止螺母出现裂纹以致损坏,利用ABAQUS有限元分析软件,使用控制变量法分析了收口深度、收口速度及收口盘圆角半径3个收口工艺的不同参数值对螺母表面残余应力分布的影响规律,并通过实验结果与仿真结果对比,验证了有限元仿真结果的准确性。结果表明:螺母的圆柱部分呈现残余压应力、圆弧部分为残余拉应力,轴线方向(S22方向)的残余应力最大;螺母表面残余应力分布随收口深度和收口速度的变化呈现相同的趋势;收口盘圆角半径对螺母表面残余应力的集中现象有较大的影响。最后实验结果表明,与有限元仿真预测趋势相吻合,偏差较小。

In order to control the residual stress on the surface of nut to prevent the nut from cracking and damage,the influence laws of different parameters of three necking processes,such as necking depth,necking speed and fillet radius of necking disk on the residual stress distribution on the surface of nut were analyzed by finite element analysis software ABAQUS,and the accuracy of finite element simulation results was verified by comparing the experimental results with the simulation results.The results show that the cylindrical part of nut exhibits residual compressive stress,the arc part is residual tensile stress,and the residual stress in the axial direction( S22 direction) is the largest.Furthermore,the residual stress distribution on the surface of nut shows the same trend with the change of necking depth and necking speed,and the fillet radius of necking disk has a great influence on the residual stress concentration on the surface of nut.Finally,the experimental results show that the they are consistent with the trend predicted by the finite element simulation,and the deviation is small.