Research Progress on Ultrasonic Assisted Friction Stir Welding of Aluminum Alloy
SHI Lei 1 , XIAO Yichen 1 , WU Chuansong 1 , SU Hao 1 , LIU Xiaochao 2 , GAO Song 3
1. Shandong University, Jinan 250061, China;
2. Southeast University, Nanjing 211189, China;
3. Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Abstract：Ultrasonic assisted friction stir welding (UaFSW) is a novel variation of conventional friction stir welding (FSW), which utilizing the external ultrasonic vibration energy to improve the inherent disadvantages of conventional friction stir welding. This article reviews the progress status on ultrasonic assisted friction stir welding of aluminum alloy, including the methods to superimposing ultrasonic vibration energy in FSW, the effects of superimposing ultrasonic vibration energy on the microstructural evolution and mechanical properties of the joints, and the mechanism of superimposing ultrasonic energy in FSW. It shows that UaFSW can reduce the welding loads, improve the joint formation, suppress the weld defects, increase the welding speed, and enhance the joint properties. Multi-physical numerical simulation of UaFSW process shows that all the thermal effect, acoustoplastic effect and friction reduction effect lead to a several difference in thermal processes and plastic material flow comparing with conventional FSW, which resulting in an improved joint formation and mechanical properties as state above. Finally, the challenges and future research topics are emphasized systematically.
2022, 
