关键词: 单边摩擦铆焊, 无预制孔连接, 铝合金, 铆钉镀层, 失效机理

Abstract: Rivet coating was a key factor influencing the formation and mechanics performances of riveted joints. The SSFR processes were used to join 6005A-T6 and 6A01-T5 aluminum alloy sheets herein. Three types of rivets including non-coated, Zn coated, and ZnNi coated were utilized to study the evolution laws of riveting force, energy input, and formation of the SSFR joints. Moreover, the remaining thickness of the coating layers at different positions in the joints and the diffusion of coating elements at the rivet/sheet interfaces was analyzed, and the influences of the rivet coating on the tensile-shear and cross-tension performances of the joints were investigated. The results indicate that the coating reduces the energy input generated by rivet rotation, thereby reducing the heat-affected zones of aluminum alloy materials. However, the decrease in energy input is not conducive to the formation of solid phase bonding between aluminum alloy materials in the rivet cavity, resulting in a decrease in the tensile-shear and cross-tension performances of the joints. Compared with Zn coating, the ZnNi coating has stronger wear resistance, and the remaining thickness still exceeds 40% after the stirring friction caused by high-speed rotation of rivets, which helps to improve the corrosion resistance of joints.

Key words: single-sided friction riveting(SSFR), joining without prefabricated hole, aluminum alloy, rivet coating, failure mechanism