铝合金搅拌摩擦焊型材公差对其焊接性能的影响

Effect of profile tolerance on welding performance for aluminum alloy FSW

搅拌摩擦焊焊接接头尺寸对焊接接头力学性能、焊接速度、焊接过程的稳定性等均有非常重要的影响。研究轨道交通用3.5 mm铝合金搅拌摩擦焊接头在不同公差状态下的焊缝组织结构与性能,对公差大幅偏离标准值条件下的焊缝性能进行了对比,结果表明:接头上下搭接间隙大于0.4 mm时,焊缝极易出现焊接缺陷,焊缝工艺窗口较窄;在转速为1 600 r/min、焊速为1 200 mm/min的焊接工艺参数下,随着焊接间隙的增大,焊缝性能呈现显著下降趋势。

The size of friction stir welding joint has a very important influence on its mechanical properties, welding speed and stability of welding process. The microstructure and properties of friction stir welded joints of 3.5 mm aluminum alloy for rail transit under different tolerance states were studied. The weld performances under the condition that the tolerance deviated greatly from the standard value were compared. The results show that when the upper and lower overlap gap of the joint is greater than 0.4 mm, the weld is easy to appear welding defects, and the welding process window is narrow;when the rotate speed is 1 600 r/min and welding speed is 1 200 mm/min, the weld performance decreases significantly with the increase of welding gap.