关键词: 轻量化, 自冲铆接, 数值模拟, 力学性能, 失效形式, 微观分析

Abstract: Self-pierce riveting technology, as a new connection technology, has excellent connection performance in the connection of thin plate materials and has a wide application scenario in the aerospace industry. 5A06 aluminum alloy and TA1 titanium alloy thin plate were selected for self-piercing riveting, and the forming process was subjected to finite element analysis. The effects of different materials and temperatures on the static mechanical properties and failure forms of the joint were investigated by conducting tensile-shear tests at room temperature and -30 ℃ environment. The results showed that the homogeneous joints were formed with good symmetry, and the cavities were easy to appear in the riveted harder plates; the average peak load of the joints decreased at low-temperature environment, but the average failure displacement and the average energy absorption increased significantly, which improved the cushioning and shock absorption ability of the joints; the average peak load of 5A06-5A06 joints (SAA joints) decreased by 13.6 % at -30 ℃, and the average peak load of TA1-TA1 joints (STT joints) showed a 6.6 % decrease at -30 ℃, which indicates that STT joints have better low-temperature resistance; under both room-temperature and low-temperature environment, SAA joints failed by pull-off and plastic deformation occurred at the failure point, STT joints showed an increase in the number of rivet cracks at low temperature, with brittle fracture at the beginning of crack expansion and ductile fracture at the edge of expansion.

Key words: lightweighting, self-piercing riveting, numerical simulation, mechanical properties, failure forms, microscopic analysis