Metallographic structure,mechanical properties,and process parameter optimization of 5A06 joints formed by ultrasonic-assisted refill friction stir spot welding  

作　　者：Xin-bo Liu Feng-bin Qiao Li-jie Guo Xiong-er Qiu 

机构地区：[1]Hunan Provincial Key Laboratory of Grids Operation and Control on Multi-Power Sources Area,Shaoyang University,Shaoyang 422000,China [2]Shanghai Aerospace Equipment Manufacturer,Shanghai 200245,China

出　　处：《International Journal of Minerals,Metallurgy and Materials》2017年第2期164-170,共7页矿物冶金与材料学报（英文版）

基　　金：financially supported by Hunan Science and Technology Research Projects(Nos.2016GK2021 and 2016TP1023);Hunan Provincial Natural Science Foundation of China(No.2016JJ4082)

摘　　要：Novel hybrid refill friction stir spot welding （RFSSW） assisted with ultrasonic oscillation was introduced to 5A06 aluminum alloy joints. The metallographic structure and mechanical properties of 5A06 aluminum alloy RFSSW joints formed without ultrasonic assistance and with lateral and longitudinal ultrasonic assistance were compared, and the ultrasonic-assisted RFSSW process parameters were opti- mized. The results show that compared with lateral ultrasonic oscillation, longitudinal ultrasonic oscillation strengthens the horizontal bond- ing ligament in the joint and has a stronger effect on the joint＇s shear strength. By contrast, lateral ultrasonic oscillation strengthens the ver- tical bonding ligament and is more effective in increasing the joint＇s tensile strength. The maximum shear strength of ultrasonic-assisted RFSSW 5A06 aluminum alloy joints is as high as 8761 N, and the maximum tensile strength is 3679 N when the joints are formed at a tool rotating speed of 2000 r/rain, a welding time of 3.5 s, a penetration depth of 0.2 mm, and an axial pressure of 11 kN.Novel hybrid refill friction stir spot welding （RFSSW） assisted with ultrasonic oscillation was introduced to 5A06 aluminum alloy joints. The metallographic structure and mechanical properties of 5A06 aluminum alloy RFSSW joints formed without ultrasonic assistance and with lateral and longitudinal ultrasonic assistance were compared, and the ultrasonic-assisted RFSSW process parameters were opti- mized. The results show that compared with lateral ultrasonic oscillation, longitudinal ultrasonic oscillation strengthens the horizontal bond- ing ligament in the joint and has a stronger effect on the joint＇s shear strength. By contrast, lateral ultrasonic oscillation strengthens the ver- tical bonding ligament and is more effective in increasing the joint＇s tensile strength. The maximum shear strength of ultrasonic-assisted RFSSW 5A06 aluminum alloy joints is as high as 8761 N, and the maximum tensile strength is 3679 N when the joints are formed at a tool rotating speed of 2000 r/rain, a welding time of 3.5 s, a penetration depth of 0.2 mm, and an axial pressure of 11 kN.

关 键 词：aluminum alloys friction stir welding ultrasonic applications METALLOGRAPHY mechanical properties parameter optimization 

分 类 号：TG453.9[金属学及工艺—焊接]