网格畸变处理技术在不锈钢多层焊应力模拟的应用  

Mesh distortion modification in stress simulation of multilayer welded stainless steel plate

作　　者：孙鲁阳 李晓延[1] 申博文 吴奇 

机构地区：[1]北京工业大学焊接研究所,北京110124

出　　处：《焊接学报》2018年第11期108-113,118,共7页Transactions of The China Welding Institution

摘　　要：通过对304 L不锈钢多层焊焊接工艺研究,利用ABAQUS有限元软件,采用热—力顺序耦合分析方法进行多层焊应力场的有限元数值计算.奥氏体不锈钢焊接性使得焊缝金属在模拟焊接过程中出现大变形导致计算网格发生畸变,计算中止.采用了"追踪单元"技术和网格重划分技术对应力场计算中网格畸变问题进行解决.将数值模拟结果与实际应力测量结果进行对比.结果表明,采用上述方法能够得到较准确的焊接残余应力结果.In the investigation of welding of 304 L austenitic stainless steel plate, the finite element numerical simulation of the stress field of multi-layer welded joints was performed by using a thermo-mechanical coupling analysis. A commercial software ABAQUS was employed for the simulation. The significant distortion of the elemental meshes of weld metal were found in the simulation due to the unique thermo-mechanical properties of the austenitic stainless steel,consequently, the abnormal outputs were frequently encountered. In this work, a tracking-unit technique and a mesh reconstruction technique were introduced in order to solve the mesh distortion problem. The numerical simulation results were compared with that of residual stress measurements. The simulated stresses were found in good agreement with the measured data in various constraint conditions. The above results may suggest that the mesh distortion modification technique could be used in the simulation of multi-layer welding of other materials.

关 键 词：多层焊 数值模拟 网格畸变 应力场 

分 类 号：TG404[金属学及工艺—焊接]