AZ71镁合金TIG焊焊接接头微观组织与力学性能  

Microstructure and Mechanical Properties of Joints of AZ71 Alloy by TIG Welding

作　　者：武婧亭[1] 游国强[1,2] 郭强[1] 龙思远[1,2] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400030 [2]国家铁合金材料工程技术研究中心,重庆400030

出　　处：《热加工工艺》2011年第1期117-118,122,共3页Hot Working Technology

基　　金：重庆市科技攻关项目(Cstc2009AB4010)

摘　　要：采用钨极氩弧焊接方法对2.2mm厚镁合金AZ71薄板进行焊接加工。焊后对接头进行拉伸试验和硬度测试,结果表明:采用90A的电流焊接时,接头抗拉性能最好(281.23MPa),达到母材的89.58%。断裂发生在焊缝区,焊接接头断口呈准解理断口,接近解理断口;母材断裂为延性断裂,断口呈韧窝断口;焊缝区显微硬度最高,其次是母材,热影响区硬度最低。AZ71 alloy with 2.2 mm thickness was welded by TIG welding.After welding,the tensile test and hardness test of the welded joint shows that,when the current is 90 A,the tensile strength reaches the maximum（281.23MPa）,up to 89.58% of the base metal.The failure occurs in the weld zone,the fracture morphology is in quasi-cleavage fracture.The fracture of the base metal is in dimpled failure mode.The hardness of the weld zone is higher than that of matrix and the hardness of heat affected zone（HAZ） is lowest.

关 键 词：AZ71镁合金 TIG焊 焊接接头 抗拉强度 硬度 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG444.74[金属学及工艺—金属材料]