铝合金双主轴回抽式搅拌摩擦焊温度场分析

Temperature field analysis of refilling friction stirring welded aluminum alloy plates

采用有限元法,对2219铝合金双主轴回抽式搅拌摩擦焊温度场进行模拟.研究表明:热量自适应热源模型能够比较准确地预测铝合金搅拌摩擦焊焊接温度场.搅拌摩擦焊焊接温度循环曲线对焊缝的横向位置敏感,焊缝中心区域的温度循环曲线在高温区段会形成温度缓升的平台,平台停留时间与轴肩直径和焊接速度相关.逐渐远离焊缝中心的区域,温度循环曲线接近熔焊.搅拌针回抽过程不影响焊缝表面的温度分布,但对工件厚度方向的温度有一定的影响,随着回抽的进行,搅拌针底部与工件接触部分的中心温度逐渐降低.

The temperature field of 2219 Al plate during friction stirring weld（ FSW） was analyzed by using finite element method in this work. The results show that the auto-adapting heat source model can be used to accurately predict the temperature field of the refilling FSW. The temperature curve was sensitive to the horizontal location of weldment. The temperature curve of high temperature zone inside the weldment would form a slow upward trend. And the dwell time at the high temperature zone was related with the diameter of the shoulder and welding speed. The welding temperature curve in FSW was similar to that in the common fusion welding far away from the weldment. The withdrawing of pin had little effect on the surface temperature,while affected the temperature distribution along the depth direction. The temperature in the center of Al plate beneath the pin decreased gradually with the withdrawing process of pin.