钢/铝异种金属光纤激光焊接数值模拟

摘要

In order to study the temperature distribution for laser butt welding of dissimilar metal steel/aluminum, a mathematical model was established and welding temperature field was also simulated by ANSYS software. Temperature distribution at different time and the thermal cycling profile at the node on specimen surface were obtained. The effect of welding speed on welding temperature field was studied. The results were compared with the actual welding. The results show that, the welding temperature field is asymmetrically distributed and the temperature gradient in steel side is greater than that in aluminum side;With the increase of welding speed, the maximum temperature reduces gradually and weld width also decreases gradually. The weld shapes obtained from simulation and experiments are consistent, and the error is less than 5%. The study can verify the accuracy of simulation results.%为了研究钢/铝异种金属激光深熔焊接的温度分布情况,采用有限元ANSYS软件建立了钢/铝异种金属激光对接焊的数学模型,对焊接温度场进行了模拟.通过计算模拟得到了不同时刻的温度场分布云图、试件表面节点的热循环曲线以及焊接速率对温度场变化的影响,并与实际焊接试验结果进行了对比.结果表明,焊接温度场呈非对称分布,钢一侧的温度梯度大于铝合金一侧的温度梯度;随着焊接速率的增大,热源中心的最高温度会逐渐降低,焊接熔池的熔宽也会随之逐渐变小.模拟的焊缝形状与实际焊接实验得到的焊缝截面的熔合线基本一致,熔池熔宽的模拟结果与实验结果误差在5%以内,验证了模拟结果的准确性.