异质铝合金激光深熔焊热固耦合数值模拟研究

Numerical Simulation of the Couple of Thermal and Stress in Deep Penetration Laser Welding of Heterogeneous Aluminum Alloys

为提高车用动力电池极耳焊接质量,基于ANSYS仿真平台建立1050/6061异质铝合金薄板非线性瞬态热固耦合分析模型,通过APDL语言完成高斯面热源的移动加载。模拟在给定工艺参数下激光深熔焊温度场与应力场,并将模拟结果与试验结果对比分析。结果表明,模拟的熔池形状和大小与试验结果吻合良好,具有可靠性。激光束加热和冷却速度极快,热源附近温度梯度大,等温线密集。焊缝中心处的应力集中是导致焊接接头产生细微裂纹等缺陷的主要原因,焊后有必要通过退火处理来降低等效残余应力。

To enhance the welding quality of vehicle power battery pole ears,a nonlinear transient thermo-structural coupling analysis model was developed for 1050/6061heterogeneous aluminum alloy sheets using the ANSYS simulation platform.The Gaussian surface heat source was applied using APDL language,and the temperature and stress fields of laser deep penetration welding were simulated under specified process parameters.The simulated molten pool shape and size were compared with experimental results,showing good agreement and reliability.The rapid heating and cooling of the laser beam resulted in a large temperature gradient near the heat source and dense isotherms.Stress concentration at the weld center was identified as the main cause of small cracks and other defects in the welded joint,suggesting the need for annealing treatment to reduce equivalent residual stress after welding.