应力迭代法重构电弧增材AA7075铝合金薄壁件残余应力场研究

Residual stress field of wire arc additive manufacturing AA7075 aluminum alloy thin-walled parts by stress iteration method

残余应力是影响电弧增材制造构件疲劳寿命的关键因素,传统的测量与仿真难以完整高效地分析增材构件的残余应力分布。为此基于本征应变相容原理,提出一种通过应力迭代重构电弧增材AA7075铝合金薄壁件残余应力场的新方法。该方法使用有限的残余应力实测数据与基函数构造应力分量,并使用APDL语言对ANSYS进行二次开发,将应力分量映射至有限元模型迭代重构残余应力场。结果表明,重构的残余应力场与X射线衍射法实测值、热弹塑性模型仿真值误差较小,证明了该方法用于电弧增材薄壁件的全局残余应力场重构的有效性。

The residual stress is a key factor affecting the fatigue life of wire arc additive components.It is difficult to analyze the residual stress distribution of additive components completely and efficiently by traditional measurement and simulation.Based on the principle of eigenstrain compatibility,a new method was proposed to reconstruct the residual stress field of AA7075 aluminum alloy thin-walled by stress iteration.In this method,the finite residual stress data and basis function were used to construct the stress component,APDL language was used for secondary development of ANSYS,and the stress component was mapped to the finite element model to reconstruct the residual stress field iteratively.The results showed that the reconstructed residual stress field had little error with the measured value of X-ray diffraction method and the simulated value of thermos-elastoplastic model,which proved the effectiveness of this method on reconstructing the global residual stress field of wire arc additive manufacturing thin-walled parts.