X80管线钢多道激光-MIG复合焊残余应力分析  

Analysis of welding residual stress in multi-pass hybrid laser-MIG welded X80 pipeline steel

作　　者：严春妍[1] 张浩[1] 朱子江 张可召 顾正家 王宝森[2] YAN Chunyan;ZHANG Hao;ZHU Zijiang;ZHANG Kezhao;GU Zhengjia;WANG Baosen(Hohai University,Changzhou,213022,China;Baosteel Central Research Institute,Shanghai,200431,China)

机构地区：[1]河海大学,常州213022 [2]宝钢集团中央研究院,上海200431

出　　处：《焊接学报》2021年第9期28-34,41,I0002,I0003,共10页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51804097);江苏省研究生科研创新计划项目(B200203154).

摘　　要：采用试验和数值模拟结合的方法对X80管线钢多道激光-MIG复合焊焊接过程的温度场和焊接残余应力场进行了研究,分析了激光功率对复合焊接头的显微组织、温度分布和残余应力分布的影响规律.结果表明,激光功率增加,熔池最高温度明显上升,焊后冷却速度下降;粗晶热影响区组织中粒状贝氏体、针状铁素体增加,条状贝氏体减少.X80管线钢激光-MIG复合焊接头残余应力水平较高,纵向残余应力、横向残余应力和厚度方向残余应力的拉应力峰值均出现在焊缝区.激光功率在2.0~3.5 kW范围时,等效残余应力、纵向残余应力、横向残余应力和厚度方向残余应力的峰值随着激光功率增加均出现下降趋势.但激光功率从3.5 kW上升至4.0 kW时,各应力的峰值有所上升.Combined experimental and numerical investigation of temperature field and residual stress field of X80 pipeline steel multi-pass hybrid laser-MIG welding were performed.Influence of laser power on microstructures,temperature distribution and residual stress distribution in the hybrid welded joints were analyzed.The results show that rising maximum temperature of the molten pool and decreasing post-welding cooling rate were obtained with increasing laser power.More acicular ferrite and granular bainite,less lath bainite formed in the coarse grained heat affected zone.Overall residual stress level in the X80 pipeline steel hybrid welded joints were high with peak tensile stress occurred in the weld metal for longitudinal stress,transverse stress and through-thickness stress.In the laser power range from 2.0 to 3.5 kW,peak stress of Von Mises equivalent stress,longitudinal stress,transverse stress and through-thickness stress all decreased with increasing laser power.However,peak stress of the stresses increased with laser power increasing from 3.5 kW to 4.0 kW.

关 键 词：激光电弧复合焊 复合热源模型 显微组织 温度场 残余应力 

分 类 号：TG404[金属学及工艺—焊接]