TC4钛合金搅拌摩擦搭接焊的温度场模拟

Numerical Simulation of Temperature Field during Friction Stir Lap Welding of TC4 Titanium Alloy

建立了TC4钛合金搅拌摩擦搭接焊的有限元模型,基于温度测试结果设置了搅拌摩擦搭接焊的边界条件,进行了搅拌摩擦搭接焊温度场的数值模拟,并对温度模拟结果与测温试验结果进行了对比。结果表明,温度模拟曲线与实测温度曲线趋势相同,二者的焊接温度峰值相差较小;焊接温度峰值随焊接速度的增加而减小。焊缝温度峰值出现在与搅拌头直接接触的区域,位于搅拌头作用区的后方。焊缝区域的温度场沿板厚方向呈上宽下窄的碗型形貌分布。

The finite element model of friction stir lap welding （FSLW） of TC4 titanium alloy was established, and the boudary conditions of friction stir lap welding were set up based on temperature measurement results. The numerical simulation of the FSLW temperature field was carried out, and the temperature simulation results were compared with the experimental results. The results show that the temperature simulation curve has the same trend with the measured temperature curve, and the difference of the two welding temperature curves＇ peak is small. The welding temperature peak decreases with the increase of welding speed. The temperature peak of the weld appears in the region of direct contact with the stirring head, which is located at the rear of the stirring head zone. The temperature field in weld zone along the plate＇s thickness direction is distributed in bowl shape of upper with wide width and lower with narrow width.