50mm厚SA508Gr.3Cl.2钢超窄间隙激光填丝焊接头组织与性能  

Microstructures and Properties of 50 mm Thick SA508Gr.3Cl.2 Steel Welding Joints by Ultra-Narrow-Gap Laser Welding with Filler Wire

作　　者：张益文 张茂龙 孙志远 黄坚[1,3] 姚成武 金鑫[1] 

机构地区：[1]上海交通大学材料科学与工程学院上海市激光制造与材料改性重点实验室,上海200240 [2]上海电气核电设备有限公司,上海200245 [3]高新船舶与深海开发装备协同创新中心,上海200240

出　　处：《中国激光》2017年第11期81-88,共8页Chinese Journal of Lasers

基　　金：国家科技重大专项(2014ZX06002001);上海市重大技术装备研制专项(ZB-ZBYZ-03-11-0485)

摘　　要：采用超窄间隙坡口和光纤激光填丝多层焊工艺,焊接了50mm厚的SA508Gr.3Cl.2核电用钢,测试并分析了接头的微观组织和性能。结果表明,焊接接头无宏观缺陷;热处理后接头中部焊缝中心组织主要为上贝氏体和针状下贝氏体,母材侧热影响区的粗晶区组织为高温回火马氏体,硬度为280HV。焊接接头拉伸试样的拉伸断裂位置均位于母材,接头抗拉性能良好。接头上、中、下部位的焊缝冲击韧性均小于母材的,但焊缝冲击试样的断口形貌仍具有一定的韧性断裂特征。By the multi-pass fiber laser welding technique with filler wire based on the ultra-narrow-gap grooves, the 50 mm thick SA508Gr.3Cl.2 nuclear power steel is welded, and the microstructures and properties of joints are tested and analyzed. The results show that there are no macro defects inside the welded joints. After heat treatment, the central organization of the welds in the middle of joints mainly consists of upper bainite and acicular lower bainite, the coarse grain area in the heat affected zone near the base material consists of high-temperature tempered martensite, and the microhardness of this area is 280 HV. The tensile fracture position of welding joints is located in the base material, which indicates that the tensile strength of joints is good. The impact toughness of the welds in the top, middle and bottom area of joints are smaller than that of the base material, but the fracture morphology of the impact specimen extracted from the welds has certain characteristics of toughness fracture.

关 键 词：激光技术 光纤激光 SA508Gr.3Cl.2钢 超窄间隙激光填丝焊接 微观组织 力学性能 

分 类 号：TG456.7[金属学及工艺—焊接]