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建立了奥氏体不锈钢圆管多层对焊残余应力的数值计算模型，该模型考虑了焊接过程中高温引起材料的物理性能常数和力学性能常数变化带来的非线性。焊接温度场采用三角差分法计算，在此基础上利用热弹塑性有限单元法计算分析了1Cr18Ni9Ti钢管多层对焊的残余应力分布。结果表明，这种钢管多层对焊后存在很大的残余应力，尤以圆管内表面焊缝附近区域的双向拉伸残余应力最大。这一结论已被残余应力实测及应力腐蚀敏感性实验所证实，表明在正常焊接工艺条件下多层对焊1Cr18Ni9Ti钢管受焊接残余应力的影响，其抗应力腐蚀性能较差。
A numerical model of the residual stress of multilayer butt welds of austenitic stainless steel tube was established. The model considers the nonlinearity caused by the change of the physical property constants and the constants of mechanical properties caused by the high temperature in the welding process. The welding temperature field is calculated by the method of triangulation. Based on this, the residual stress distribution of multi-layer butt-welded 1Cr18Ni9Ti steel pipe is calculated and calculated by the thermo-plastic finite element method. The results show that there is a great residual stress after multi-layer butt welding of this kind of steel pipe, especially the biaxial tensile residual stress in the area near the weld on the inner surface of the pipe is the largest. This conclusion has been confirmed by residual stress measurement and stress corrosion sensitivity experiment, which shows that the multi-layer butt welding 1Cr18Ni9Ti steel pipe under normal welding conditions is affected by welding residual stress and its resistance to stress corrosion is poor.