基于SIGINI子程序的零件残余应力变形数值模拟研究

Numerical Simulation of Deformation of Parts Due to Residual Stress Based on SIGINI Subroutine

为提高飞机性能,整体结构件成为飞机广泛采用的主要承力构件,而整体结构件毛坯由于残余应力的存在往往导致加工后出现较大变形影响零件精度。根据模锻毛坯件的残余应力测试试验数据,逆向构建了初始应力仿真模型,采用用户子程序SIGINI施加初始应力场,运用生死单元法对分层材料进行去除。结果表明,通过表层残余应力试验数据逆向构建初始残余应力分布场计算变形的可行性,同时可以直观分析生死单元法逐层杀死单元过程中,初始残余应力的释放过程,与零件加工后的变形测量结果对比,有较高的吻合性。

In order to improve the performance of aircraft,the integral structure is widely used as the main load-bearing component,and the blank of the integral structure is often deformed after machining due to the existence of residual stress,which affects the precision of the parts.Based on the experimental data of residual stress test of die forging blank,the initial stress simulation model is constructed in this paper.The initial stress field is applied by the user subprogram SIGINI,and the stratified material is removed by the birth and death element method.The simulation results verify the feasibility of inverse constructing the initial residual stress distribution field through the surface residual stress experimental data to calculate the deformation.At the same time,the release process of the initial residual stress can be analyzed intuitively in the process of killing the unit layer by the birth and death element method.Compared with the results of deformation measurement after machining,the results are in good agreement with each other.