用奥氏体焊条焊接9% Ni钢马氏体层组织及接头的断裂韧性

The Affect of Martensite Laryer at Weld Bond On the Fracture Toughness of 9%Ni Steel Joints Welded by Austenitic Electrodes OK69.45

摘要: 采用光学金相显微镜和透射电子显微镜分析了用奥氏体焊条OK69.45焊接的9%Ni钢接头熔合区和HAZ的组织;设计了特殊的试样测试了熔合区和HAZ过热区的断裂韧性COD值,并对断口进行了分析。结果表明:熔合区马氏体层的组织为板条状马氏体;熔合区的断裂韧性COD值与HAZ过热区COD值相差不大,马氏体层的存在并没有恶化接头的断裂韧性。

Abstract: Optical microsope observarion and TEMA was used to study the microstructures at weld bond and HAZ of the 9%Ni steel joints welde by austenitic electrode-OK69.45.Special specimens were designed to measure the fracture toughness in the two regions during COD test,and the fractographic experiment was also made by SEM.The results shown that the structures in the martensite layer at weld bond is lath martensite,there is no significant difference in the COD valie between weld bond and over heated zone.The existence of martensite laryer does not reduce fractuer toughness value of the joints.