送丝速度对5083铝合金等离子-MIG复合焊接头性能的影响  

Influence of wire feed speed on properties of 5083 aluminum alloy welded joint by plasma-MIG hybrid welding

作　　者：孙家帅 张焱 零的应 姚宗湘[1,2] 尹立孟 王刚[1] 陈玉华[2] SUN Jiashuai;ZHANG Yan;LING Diying;YAO Zongxiang;YIN Limeng;WANG Gang;CHEN Yuhua(Chongqing University of Science and Technology,Chongqing 401331,China;Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]重庆科技学院,重庆401331 [2]南昌航空大学,江西南昌330063

出　　处：《电焊机》2021年第10期143-147,I0010,共6页Electric Welding Machine

基　　金：国家自然科学基金(52175288);重庆市自然科学基金(cstc2020jcyj-msxmX0552);江西省航空构件成形与连接重点实验室开放课题(HKGJ-2001);重庆科技学院研究生科技创新项目(YKJCX2020227);重庆科技学院大学生科技创新训练计划项目(2021203);重庆市大学生创新训练计划项目(S202011551006)。

摘　　要：对厚度5 mm的5083铝合金进行等离子-MIG复合焊接,研究不同送丝速度对焊缝成形与焊接接头性能的影响,分析接头的微观组织,并测试接头的力学性能。结果表明:送丝速度为7 m/min、9 m/min时均可获得无明显缺陷的焊接接头,送丝速度增大,余高略有增加;送丝速度为9 m/min的焊接接头焊缝区的树枝状晶更加细小,接头硬度分布呈"W"形,焊缝区和熔合区的平均硬度均低于母材,距焊缝中心3~4 mm处的熔合区硬度最低,送丝速度为7 m/min时,其接头软化现象更为显著。两种送丝速度下的接头拉伸断裂均出现在熔合区附近,送丝速度为9 m/min的焊接接头的抗拉强度和延伸率均高于7 m/min的,断裂形式均为韧性断裂。Plasma-MIG hybrid welding was carried out on 5 mm thick 5083 aluminum alloy. The influence of wire feed speed on the weld appearance and properties of welded joints were studied. The microstructure of the joint was analyzed and the mechanical properties of the joint were tested. The results show that both wire feed speeds can obtain welded joints without obvious defects, and the reinforcement increases slightly when the wire feed speed improves. The dendrites in the weld zone of welded joints with wire feed speed of 9 m/min are smaller than those with wire feed speed of 7 m/min. The microhardness distribution of the welded joint is "W" shaped. The average hardness of weld zone and bond are lower than that of the base metal. The minimum hardness occurs in the bond that is 3 ~4 mm distant from the weld center. When the wire feed speed is 7 m/min, the joint softening is more obvious. Both tensile fractures of the joints at these two wire feed speeds occur near the bond. The tensile strength and elongation of welded joints at wire feed speed of 9 m/min are higher than those at 7 m/min.The fracture form is a typical toughness fracture.

关 键 词：5083铝合金 等离子-MIG焊 显微组织 力学性能 软化 

分 类 号：TG457.14[金属学及工艺—焊接]