Comparative study on numerical simulation of laser welding and resistance spot welding for side wall of stainless steel railway vehicle

不锈钢轨道客车侧墙激光焊接与电阻点焊数值模拟对比研究 Comparative study on numerical simulation of laser welding and resistance spot welding for side wall of stainless steel railway vehicle 王春生 WANG Chunsheng 1 first-author 王文权 WANG Wenquan 2 王洪潇 WANG Hongxiao 1 徐国成 XU Guocheng 2 中车长春轨道客车股份有限公司 中车长春轨道客车股份有限公司 Engineering Technology Center,CRRC Changchun Railway Vehicles Co.,Ltd. Engineering Technology Center,CRRC Changchun Railway Vehicles Co.,Ltd. 吉林大学材料学院 吉林大学材料学院 Department of Materials Science and Engineering,Jilin University Department of Materials Science and Engineering,Jilin University 针对激光焊接工艺和电阻点焊工艺在不锈钢轨道客车侧墙组上的应用进行了数值模拟对比分析。分别测试SUS301L不锈钢薄板激光焊接和电阻点焊搭接的侧墙结构件的拉剪强度。结果表明,对于相同长度的接头,激光焊接接头的力学性能比电阻点焊接头更好。在施加相同载荷条件下,对两种焊接接头的应力和应变进行了数值模拟研究。结果表明,应力集中现象和最高应力水平均出现在电阻点焊接头中,理论分析和实验结果都证明激光焊接的轨道客车侧墙受力更均匀、变形更小、外观质量更好。 The Ar+CO2 gas shielded welding method was used in the condition of non-preheating,and the low-alloy basic slag flux-cored wire was selected to weld Q620 steel under three heat inputs. The weldability and engineering usability of high strength and low alloy Q620 steel were studied by welding joint quality analysis,weld metal chemical composition analysis,microstructure observation and mechanical property test. The results show that Q620 steel has good weldability at room temperature,and the alloying elements in the weld zone are evenly distributed. When the welding heat input changes from low to high,the microstructure of the weld zone changes from ferrite +pearlite to bainite +martensite,and the strength and hardness of the weld zone decrease. With the increase of heat input,the impact fracture morphology of weld zone changes from ductile fracture to hybrid fracture mode of dimple and quasi-cleavage. 激光焊接 电阻点焊 不锈钢轨道客车 侧墙组成 有限元数值模拟 laser weld joint resistance spot welding stainless steel railway vehicle side wall composition finite element numerical simulation U270.6;TG457.11 2022-03-08 7 50