基于自适应面-体热源模型的6005A-T6铝合金静止轴肩搅拌摩擦焊温度场数值模拟

Numerical Simulation of Temperature Field of 6005A-T6 Aluminum Alloy Static Shoulder Friction Stir Welding Based on Adaptive Surface-Body Heat Source Model

以3 mm厚6065A-T6铝合金板为研究对象,利用ABAQUS软件模拟静止轴肩搅拌摩擦焊接过程中温度场以及焊缝区域各点的热循环曲线,研究不同焊接速度对焊缝区域温度峰值的影响规律。结果表明:随着焊接速度的增大,热源中心的峰值温度逐步降低,焊核高温区域面积明显减小。常规搅拌摩擦焊横截面温度云图呈上宽下窄的“碗状”分布,而静止轴肩搅拌摩擦焊的则类似于搅拌针的“锥形”形貌。在相同工艺参数下,静止轴肩搅拌摩擦焊相比于常规焊接工艺,能使焊核区域峰值温度降低大约30℃,所得的横截面温度场分布也更均匀。金相实验观测到的接头横截面形貌与模拟结果相匹配,有限元模拟结果与温度场实测结果良好吻合,说明所建立的自适应面-体热源模型能指导和预测实际焊接过程。

Taking the 3 mm-thick 6065A-T6 aluminum alloy plate as the research object,the temperature field and thermal cycle curve of each point in the weld area during the static shoulder friction stir welding process are simulated by ABAQUS software,and the influences of different welding speeds on the peak temperature in the weld area are studied.The results show that with the increase of welding speed,the peak temperature in the center of the heat source decreases gradually,and the area of the high temperature zone of the weld nugget decreases significantly.The cross-section temperature cloud of conventional friction stir welding(FSW)shows a"bowl-shaped"distribution that is wide at the top and narrow at the bottom,while that of the static shoulder friction stir welding is similar to the cone shape of the stirring needle.Under the same process parameters,the peak temperature in the weld zone of static shoulder friction stir welding can be reduced by about 30℃compared with that of the conventional welding process,and its cross-section temperature field is more uniform.The cross-section morphology of the joint observed by metallographic experiment matches with the simulation results,and the temperature field from the finite element is in good agreement with the measured results,which shows that the adaptive surface-body heat source model established can guide and predict the actual welding process.