工艺参数对铝合金静轴肩搅拌摩擦焊焊缝成形的影响

Influence of Process Parameter on Weld Formation of Stationary Shoulder Friction Stir Welding of Aluminum Alloy

采用自主设计的静轴肩搅拌摩擦焊设备对3mm厚2024铝合金进行了搭接试验,研究了焊接速度及搅拌头旋转速度对焊缝成形的影响规律。研究表明,工艺参数不当时,焊核会形成未结合的冶金界面。焊缝表面缺陷与转移至焊缝上部的金属量有关。随着焊接速度的增加或者旋转速度的减小,焊核区宽度与界面迁移高度减小,界面迁移深度(水平迁移距离)增大。

The 3 mm thick 2024 aluminum alloy was lap welded by using self-designed stationary shoulder friction stir welding system. The influence laws of welding speed and rotational speed of stirring head on the weld formation were investigated. The results show that unbonded metallurgical interface forms in nugget zone when the process parameters are not suitable. The weld surface defect is related to the amount of metal transferring to the upper part of the weld. The width of nugget zone area and the height of interface migration decrease and the depth of interface migration in horizontal direction increases with the increase of the welding speed or the decrease of the rotational speed.