摘要
对18Ni无Co马氏体时效钢进行了真空电子束焊接,用金相显微镜观察了焊接接头的组织形貌,并测定了焊缝区、热影响区、基体的显微硬度。结果表明,18Ni无Co马氏体时效钢组织为板条马氏体组织,材料焊接性能良好,焊缝区凝固组织为胞状树枝晶,熔合线附近热影响区晶粒发生了再结晶,晶粒长大明显。硬度分布有明显的规律性,焊缝区硬度最低,细晶区硬度最高,熔合线附近的热影响区,离熔合线越远,硬度值越高。在距熔合线2.5 mm处有一个马氏体与奥氏体两相混合的狭窄区域,硬度较其两侧有明显降低。
Electron beam welding was used to weld 18 Ni Co-free maraging steels.The microstructure of welded joints was investigated by optical microscopy,and the microhardness of weld metal,heat-affected zone and base material was tested.The results show that the microstructure of the base materials is lath martensite,and the microstructure of weld metal exhibits a typical cystiform-dendritic morphology.The region adjoining the weld metal was heated to high temperatures in the austenite phase before rapid cooling.EB ...
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2008年第4期29-32,114,共5页
Transactions of The China Welding Institution
基金
国家973基金资助项目(2007CB714705)
国家自然科学基金资助项目(50771073)
关键词
无Co马氏体时效钢
电子束焊接
微观组织
硬度
18 Ni Co-free maraging steel
electron beam welding
microstructure
microhardness
