SMA490BW耐候钢不同焊接区域裂纹扩展门槛值研究  

Study on crack extension threshold value in different welding areas of SMA490BW weathering steel

作　　者：回丽[1] 仉奕霏 周松 安金岚 许良 HUI Li;ZHANG Yifei;ZHOU Song;AN Jinlan;XU Liang(Key Laboratory of Fundamental Science for National Defense of Aeronautical Digital Manufacturing Process,Shenyang Aerospace University,Shenyang 110136,China;School of Mechanical and Electrical Engineering,Shenyang Aerospace University,Shenyang 110136,China)

机构地区：[1]沈阳航空航天大学航空制造工艺数字化国防重点学科试验室,辽宁沈阳110136 [2]沈阳航空航天大学机电工程学院,辽宁沈阳110136

出　　处：《兵器材料科学与工程》2023年第2期112-116,共5页Ordnance Material Science and Engineering

基　　金：国家自然科学基金(52105157);国防重点实验室开放基金(SHSYS202003);辽宁省教育厅系列项目(LJKZ0194)。

摘　　要：对SMA490BW耐候钢MAG熔化焊接头的焊核区和热影响区在不同应力比下的裂纹扩展门槛值进行研究,比较两种焊接区域在不同应力比下的抗裂纹扩展能力,用光学显微镜观察两种焊接区域的显微组织,分析应力比和显微组织对裂纹扩展门槛值的影响。结果表明:在同一应力比下,焊核区的裂纹扩展门槛值和抗裂纹扩展能力高于热影响区;对于同种焊接区域,应力比为-1时的裂纹扩展门槛值和抗裂纹扩展能力比应力比为0时的高;焊核区组织的晶粒比热影响区粗大,导致焊核区的裂纹扩展门槛值大于热影响区。The crack propagation thresholds in the weld core zone and affected zone of MAG fusion welded joints of SMA490BWweathering steel under different stress ratios were studied,and the crack propagation resistance of the two welding areas underdifferent stress ratios was compared. The microstructure of the two welding areas was observed by optical microscope,and theeffects of stress ratios and microstructures on the crack propagation thresholds were analyzed. The results show that at the samestress ratio,the threshold value and anti-crack growth ability of weld core zone are higher than those of heat affected zone. Forthe same welding area,the threshold value of crack propagation and the ability to resist crack propagation when the stress ratio is-1 are higher than those when the stress ratio is 0. The grain size in the weld nugget zone is coarser than that in the heat affectedzone,which leads to the larger crack propagation threshold in the weld nugget zone than that in the heat affected zone.

关 键 词：SMA490BW耐候钢 裂纹扩展门槛值 MAG熔化焊焊接接头 金相组织 

分 类 号：TG405[金属学及工艺—焊接]