搅拌摩擦焊工艺对AZ31合金组织性能的影响  

Effect of Friction Stir Welding Process on Microstructure and Properties of AZ31 Alloy

作　　者：陈小江[1] 张丽红[1] 梁涛[2] CHEN Xiaojiang;ZHANG Lihong;LIANG Tao(Inner Mongolia Technical College of Mechanics ＆ Electrics,Hohhot 010070,China;Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]内蒙古机电职业技术学院,内蒙古呼和浩特010070 [2]哈尔滨工业大学,黑龙江哈尔滨150001

出　　处：《热加工工艺》2018年第13期218-222,共5页Hot Working Technology

摘　　要：研究了焊接速度、搅拌头转速对AZ31合金搅拌摩擦焊接头显微组织和力学性能的影响,分析了焊接工艺参数的作用机理。结果表明,焊接速度过低（250 mm/min）或者搅拌头转速过高（650、700 r/min）,焊核区的条带区中都会产生孔洞缺陷。随着焊接速度的增加,焊核区和热影响区的晶粒尺寸都呈现逐渐减小的趋势,合金的抗拉强度和断后伸长率都表现为先升高后降低的趋势。随着搅拌头转速的增加,焊核区和热影响区的晶粒尺寸都呈现逐渐增加的趋势,合金的抗拉强度和断后伸长率呈现先增加后减小的趋势。AZ31合金适宜的搅拌摩擦焊工艺为焊接速度400 r/min、搅拌头转速550 r/min,此时搅拌摩擦焊接头的抗拉强度和断后伸长率分别为202 MPa和5.0%,断裂位置位于后退侧热影响区。The effects of welding speed and revolving speed of stir head on the microstructure and mechanical properties of AZ31 alloy friction stir welded joint were studied, and the mechanism of the welding parameters was analyzed. The results show that when the welding speed is too low （250 mm/min） or the revolving speed of the stir head is too high （550 and 600 r/min）, hole defects appear in the strip area of nugget area. With the increase of the welding speed, the grain size of the weld nugget area and the heat affected zone decreases gradually, and the tensile strength and the elongation first increase and then decrease. With the increase of the revolving speed of the stir head, the grain size of the weld nugget area and the heat affected zone gradually increase, and the tensile strength and the elongation of the alloy increase first and then decrease. The suitable friction stir welding process of AZ31 alloy is welding speed of 400 r/min and revolving speed of stir head of 550 r/min, at this time, the tensile strength and elongation of the friction stir welded joints are 202 MPa and 5%, respectively, and the fracture location is in the heat affected zone at the retreating side.

关 键 词：AZ31合金 搅拌摩擦焊 工艺参数 组织 性能 

分 类 号：TG453.9[金属学及工艺—焊接]