2219铝合金无倾角式搅拌摩擦焊接头组织性能

Microstructure and Performance of Friction Stir Welding Joint of 2219 Al-Alloy With Zero Tilt Angle

采用基于三轴联动系统的无倾角搅拌摩擦焊方法,研究了2mm厚2219铝合金焊接试验过程,重点分析了微观组织分布特点和接头力学性能。结果表明,采用内聚花纹锥形轴肩搅拌工具,实现了无倾角搅拌摩擦焊接过程,焊缝外观及内部质量良好,但搭接界面处存在Hook现象,在前进侧呈现先向上后向下弯曲,指向焊核区的纹路特征,而后退侧呈现了向上弯曲的Hook钩状纹路;2mm厚铝合金2219无倾角式搅拌摩擦焊搭接接头拉伸剪切抗力平均为5630N,与母材抗拉力的比值为75.7%;同时,通过试验证明了无倾角搅拌摩擦焊方法对曲线焊缝的适应性。

The friction stir welding process of 2219 Al-alloy with thickness of 2mm with zero tilt angle is studied based on three axis linkage system, especially on the microstructure distribution and mechanical performances of the welding joints. The results show that the cone-shaped shoulder friction stir tools with figures could realize the friction stir welding process with zero tilt angle, and the appearance and inside qualities of joints are excellent. The Hook exists in the overlap interface. In the advancing side, the interface curves upwards first, then downwards, and points to the nugget zone. In the retreating side, the Hook curves upwards. The average value of tensile and shear resistance of 2219 Al-alloy friction stir welding overlap joint with zero tilt angle is 5630 N. And the ratio of loading capability of the joint and base metal is 75.7%. Meanwhile, the adaptability of friction stir welding with zero tilt angle on curve welding seam is proved.