对7B04铝合金回填式搅拌摩擦点焊及铆接连接的结构件的静力与疲劳性能进行对比测试. 结果表明，由铆接与回填式搅拌摩擦点焊连接的典型结构的压缩静力载荷在117 ~ 124 kN范围内波动，剪切静载荷波动范围为89 ~ 95 kN，焊点间距对载荷的影响较小；铆接连接的典型件剪切疲劳寿命低于回填式搅拌摩擦点焊结构件寿命. 对于点焊结构而言，接头微观组织不均匀导致硬度不均匀，同时搭接面处钩状结构向上弯曲，最终使得疲劳试件的失效主要沿轴肩回抽路径.
7B04 aluminum alloy was chosen as the experimental material. The static and fatigue properties of 7B04 aluminum alloy structure joined by refill friction stir spot welding (Refill FSSW) were conducted, and they were compared with that joined by riveting. Results show that the compression static load of the typical structure connected by riveting and refill FSSW fluctuated in the range of 117 —124 kN, and the shear load was in the range of 89 —95 kN. Welds spacing had a small influence on the static load of the structures joined by refill FSSW. However, the fatigue life of structures of riveting was lower than that joined by refill FSSW. For the welded structure, the heterogeneous microstructures of welding joint led to the uneven microhardness, and meanwhile the hook in the lap interface bends upwards. These factors made the fatigue structures failure along the path that sleeve moves.
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