SA508/316L异种钢焊接接头的显微组织  

Microstructure of SA508/316L dissimilar steel welding joints

作　　者：欧平[1] 孙坚[1] 张茂龙 魏一[3] 

机构地区：[1]上海交通大学材料科学与工程学院,上海200240 [2]上海电气核电设备有限公司,上海201306 [3]上海市核电办公室,上海200031

出　　处：《材料热处理学报》2013年第10期132-138,共7页Transactions of Materials and Heat Treatment

基　　金：上海市科委项目(10521100506)

摘　　要：采用ERNiCr-7(Inconel 52M)焊丝对SA508Gr.3Cl.2低合金钢与316L奥氏体不锈钢进行了填丝钨极惰性气体弧焊(TIG)试验,并利用金相显微镜、透射电子显微镜以及显微硬度计等手段对以上异种钢焊接接头的显微组织与硬度进行研究分析。结果表明焊缝金属为粗大的树枝晶状凝固组织、晶界存在M23C6碳化物,同时晶粒内部存在少量由Ti(C,N)碳氮化合物与Al2MgO4化合物共生的双层结构夹杂物;焊接接头SA508Gr.3Cl.2低合金钢存在约3 mm范围的粒状贝氏体组织热影响区(HAZ),其显微硬度明显高于母材上贝氏体组织;焊接接头316L奥氏体不锈钢不存在明显的HAZ,其显微硬度基本没有变化。SA508Gr. 3C1.2/316L dissimilar steel welding joints were produced by tungsten inert gas （TIG） welding using ERNiCr-7 （Incone152M） welding wires. Microstructure and hardness of the welding joints were investigated by optical microscope, transmission electron microscopy and microhardness test. The results show that the weld metal are composed of coarse dendritic solidification structure, ME3C6carbides precipitated along grain boundaries and a small amount double layer inclusions, which are generated by coupling growth of Ti（C,N） carbon nitrides and AIEMgO4 compounds inside grains. There exists a heat affected zone （HAZ） of about 3 mm wide granular bainite in SA508Gr. 3C1.2 low-alloy steel of the welding joints, of which the microhardness is higher than that of the upper bainite in SA508Gr. 3C1. 2 matrix. No obvious HAZ is observed in the 316L austenitic stainless steel of the welding joints, of which the microhardness almost does not change.

关 键 词：异种钢焊接接头 显微组织 显微硬度 

分 类 号：TG407[金属学及工艺—焊接]