马氏体和奥氏体不锈钢TIG焊端接接头失效分析  

Failure analysis on TIG welded joint between martensitic and austenitic stainless steels

作　　者：凌伟[1] 葛辽海[2] 任振安[3] 孙大千[3] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所,长春130033 [2]中国科学院长春应用化学研究所,长春130022 [3]吉林大学汽车材料教育部重点实验室,长春130025

出　　处：《焊接学报》2007年第5期89-92,共4页Transactions of The China Welding Institution

摘　　要：针对船舶设备采用的马氏体和奥氏体不锈钢钨极氩弧焊焊接接头的泄漏问题,采用光学显微镜和扫描电镜观察、显微硬度测定等方法,分析了1Cr17Ni2马氏体不锈钢和1Cr18Ni9Ti奥氏体不锈钢焊接接头各个区域的组织变化和硬度分布。结果表明,在1Cr17Ni2一侧的热影响区紧邻焊缝部位,铁素体受热作用明显长大,显微硬度较低,在热影响区的较高温度区,快冷得到高硬度马氏体,该区断口呈典型的解理与准解理脆性断口,成为焊接接头的薄弱地带,容易产生裂纹导致泄漏。还分析了接头失效的其它原因并提出了改进措施。Aiming at the leaking problem of the TIG welded joint between martensitic and austenitic stainless steels used in shipping facilities.Changes of microstructures and the microhardness distribution at different zones in the welded joint between 1Cr17Ni2 and 1Cr18Ni9Ti stainless steels were analyzed by optical microscope,scanning electronic microscope and microhardness tester.On the side of 1Cr17Ni2 base metal,ferrite became coarser in HAZ adjacent to the weld and its microhardness was relatively lower.At the zone in HAZ where the heated temperature was higher,martensite with high microhardness was obtained because of fast cooling.The fracture on the 1Cr17Ni2 side was cleavage and quasi-cleavage mixture,which confirmed that the HAZ of 1Cr17Ni2 base metal was the weakest area in the joint to result in the crack and leakage.The other failure reasons were also analyzed and the measures were put forward to solve the problem.

关 键 词：不锈钢 氩弧焊焊接接头 失效分析 

分 类 号：TG457.11[金属学及工艺—焊接]