C300钨极氩弧焊焊接接头组织不均匀性的分析  

Analysis on microstructures inhomogeneity of C300 tungsten inert-gas welded joint

作　　者：杨帅[1] 彭云[1] 张晓牧[1] 田志凌[1] 彭展南[2] 

机构地区：[1]钢铁研究总院先进钢铁流程及材料国家重点实验室,北京市100081 [2]北京科技大学材料科学与工程学院,100083

出　　处：《焊接》2013年第8期17-22,70,共6页Welding & Joining

基　　金：国家重点基础研究发展计划(973计划)(2010CB630800)

摘　　要：组织均匀程度对性能具有重大影响,采用光学显微镜、扫描电子显微镜对C300马氏体时效钢的钨极氩弧焊焊接接头进行了分析。研究表明,接头在焊态、焊后固溶态以及焊后固溶时效态均具有组织的不均匀性。焊缝也存在组织不均匀性,后道焊接对前道焊缝造成不同程度的固溶和时效作用,加剧了整个焊缝区组织的不均匀性。焊缝以胞状树枝晶为主,在末道焊缝中存在少量的胞状晶。高温均质化处理可以消除焊缝的胞状树枝晶形貌和合金元素偏析,实现焊缝组织和成分的均匀化,但会使得晶粒严重粗化。Microstructure has significant effect on the properties of the joint.This study was under taken to study the microstructure inhomogeneity of maraging steel(C300) tungsten inert-gas welded joint by means of optical microscopy,scanning electron microscopy.The results indicated that there exists inhomogeneity in the welded joint with the state of as welded,solution after welded and solution aging after welded.The weld also has inhomogeneity,and the inhomogeneity will be much serious because of heat effect of different weld pass.There were mainly cellular dendrites in the weld and a little cellular in the last weld.The microstructure and composition uniformity can be achieved by homogenization heat treatment which can eliminate the weld cellular dendrite morphology and segregation of alloying elements,but can cause serious grain coarsening.

关 键 词：马氏体时效钢 钨极氩弧焊 不均匀性 微观组织 

分 类 号：TG401[金属学及工艺—焊接]