超高强钢低匹配焊接接头熔合区组织特征及断裂行为研究  

Study on Microstructure and Fracture Behavior of Fusion Zone of Ultra High Strength Steel Low Matched Welded Joint

作　　者：彭杏娜[1,2] 彭先宽 杜占江[1,2] 丛相州 张强[1,2] PENG Xingna;PENG Xiankuan;DU Zhanjiang;CONG Xiangzhou;ZHANG Qiang(Beijing Guodian Futong Science and Technology Development CO.,LTD.,Beijing 102401,China;NARI Group Corporation(State Grid Electric Power Research Institute),Nanjing 211000,China)

机构地区：[1]北京国电富通科技发展有限责任公司,北京102401 [2]南瑞集团(国网电力科学研究院)有限公司,江苏南京211000

出　　处：《热加工工艺》2018年第23期44-47,51,共5页Hot Working Technology

摘　　要：对超高强钢采用了低匹配的奥氏体焊接材料进行了焊接。采用光学显微镜、扫描电镜等手段对该接头熔合区的组织进行了分析,通过原位拉伸分析手段对熔合区的局部断裂行为进行了研究。结果表明,焊接接头熔合区的化学成分不均匀,在靠近熔合线处形成了宽度不等的“富奥氏体带”,最高硬度位于富奥氏体带。原位拉伸试样均在最大载荷前起裂,裂纹起裂和扩展伴随着大量的塑性变形,断裂位置最后均位于较软的奥氏体焊缝侧,其主要断裂机制为延性断裂。The ultra-high strength steel was welded with low matching austenitic welding materials. The microstructure of fusion zone was analyzed by means of optical microscope and scanning electron microscope. The local fracture behavior of fusion zone was studied by in-situ tensile analysis. The results show that the chemical composition of the fusion zone is very heterogeneous and "austenite-rich" bands with different widths form near the fusion line, and the highest hardness is located in the "austenite-rich" zone. The in-situ tensile specimens start to crack before the maximum load. The initiation and propagation of cracks are accompanied by a large amount of plastic deformation. The fracture locations are finally located in the softer austenite weld. The main fracture mechanism is ductile fracture.

关 键 词：超高强钢 熔合区 显微组织 原位拉伸 断裂行为 

分 类 号：TG444.77[金属学及工艺—焊接] TG457