Microstructural formation and mechanical performance of friction stir double-riveting welded Al-Cu joints  

作　　者：Shude JI Zhiqing ZHANG Peng GONG Hua LIU Xiao CUI Yewei ZHANG 

机构地区：[1]College of Aerospace Engineering,Shenyang Aerospace University,Shenyang 110136,China

出　　处：《Chinese Journal of Aeronautics》2023年第8期454-471,共18页中国航空学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.51874201 and 52074184).

摘　　要：A novel friction stir double-riveting welding(FSDRW) technology was proposed in order to realize the high-quality joining of upper aluminum(Al) and lower copper(Cu) plates,and this technology employed a Cu column as a rivet and a specially designed welding tool with a large concave-angle shoulder. The formations, interfacial characteristics, mechanical properties and fracture features of Al/Cu FSDRW joints under different rotational velocities and dwell times were investigated. The results showed that the well-formed FSDRW joint was successfully obtained.The cylindrical Cu column was transformed into a double riveting heads structure with a Cu anchor at the top and an Al anchor at the bottom, thereby providing an excellent mechanical interlocking.The defect-free Cu/Cu interface was formed at the lap interface due to the sufficient metallurgical bonding between the Cu column and the Cu plate, thereby effectively inhibiting the propagation of crack from the intermetallic compound layer at the lap interface between the Al and Cu plates. The tensile shear load of joint was increased first and then decreased when the rotational velocity and dwell time of welding tool increased, and the maximum value was 5.52 k N. The FSDRW joint presented a mixed mode of ductile and brittle fractures.

关 键 词：Dissimilar Al/Cu metals Friction stir double-riveting welding Mechanical interlocking Mechanical properties Metallurgical bonding 

分 类 号：V242[航空宇航科学与技术—飞行器设计]