补焊对7050-T7451高强铝合金搅拌摩擦焊接头组织与性能的影响  

Effect of Repair Welding on the Microstructure and Mechanical Properties of Friction Stir Welded 7050-T7451 Aluminum Alloy Joints

作　　者：张兵宪 陈素明 贺餠 牛鹏亮 黄春平 ZHANG Bingxian;CHEN Suming;HE Wei;NIU Pengliang;HUANG Chunping(Avic Xi’an Aircraft Industry Group Company.Ltd,Xi’an 710089,China;School of Materials Science and Engineering,Nanchang Hangkong University,Nanchang 330063,China;First Military Representative Office of Air Force Equipment Department in Xi’an Region,Xi’an 710089,China;Graduate School of Chinese Aeronautical Establishment,Yangzhou 225111,Jiangsu,China)

机构地区：[1]中航西安飞机工业集团股份有限公司,西安710089 [2]南昌航空大学材料科学与工程学院,南昌330063 [3]空军装备部驻西安地区第一军事代表室,西安710089 [4]中国航空研究院研究生院,江苏扬州225111

出　　处：《材料导报》2025年第10期153-158,共6页Materials Reports

基　　金：国家自然科学基金(52105357)。

摘　　要：采用优化焊接工艺参数对7050-T7451高强铝合金搅拌摩擦焊接头进行了1—4次的搅拌摩擦补焊,补焊工艺参数为旋转速度600 r/min、焊接速度150 mm/min。采用光学显微镜、扫描电镜、差示量热扫描仪、显微硬度和室温拉伸对不同补焊次数接头的宏-微观组织、力学性能和断裂行为进行了分析。结果表明,在不同补焊次数下均可获得内部无缺陷的接头。搅拌区宽度随补焊次数的增加而增加。补焊后,第二相颗粒的尺寸呈减小趋势,且分布更为弥散。补焊2次接头的拉伸性能最好,抗拉强度和伸长率分别为520 MPa和8.2%,相比原焊态接头,抗拉强度和伸长率分别提升了25 MPa和46.4%。当补焊4次时,接头的断裂位置从搅拌区转移到前进侧热影响区。In order to eliminate the micro-voids in the stir zone of friction stir welded 7050-T7451 aluminum alloy,1 to 4 times of repair welding with optimized friction stir welding parameters were conducted to repair the stir zone.The repairing parameters are tool rotational rate 600 r/min,welding speed 150 mm/min.The optical microscope,scanning electron microscope,differential scanning calorimeter,microhardness tests and tensile tests at room temperature were utilized to characterize the macro/microstructure,tensile properties and fracture behavior of the repaired joints.Results indicate that sound joints without inner flaws can be obtained.The width of stir zone was increases with the increase of repairing times.The size of second phase particles decreases and homogeneously distributes after repairing.After two times repairing,the joint has the hig-hest tensile properties with tensile strength of 520 MPa and elongation of 8.2%,which are 25 MPa and 46.4% higher than those of the as-welded joint.The fracture location of joint altered from the stir zone to the heat affected zone on the retreating side when four times repairing was conducted.

关 键 词：7050-T7451铝合金 搅拌摩擦焊 补焊 微观组织 力学性能 

分 类 号：TG453.9[金属学及工艺—焊接]