异厚度铝锂合金激光焊接温度场数值模拟研究

对异厚度铝锂合金激光拼焊的温度场进行ANSYS三维瞬态有限元分析。用过渡网格划分网格以保证焊缝处网格足够细小,从而提高计算精度和效率。热源模型选取高斯函数分布,移动热源的加载则利用ANSYS软件的APDL语言编写程序实现,同时利用多步循环来实现对激光焊接过程的模拟,得到相应的温度场分布。从模拟结果可看出,激光焊接过程温度场呈椭圆分布,焊件上形成了准稳态温度场。薄厚两板温度场存在差异,薄板温度场范围、熔池尺寸、熔化范围均大于厚板。为研究材料在激光加工过程的性能改变提供参考。

Numerical simulation on temperature field in laser welding of Al-Li alloy with different thickness

By using ANSYS,the 3D transient finite element analysis of temperature field of laser welding for Al-Li alloy of different thickness were simulated.In order to improve calculation accuracy and efficiency,transition mesh dividing was used to ensure enough small mesh space on the weld.Gauss function heat source model was used and APDL of ANSYS was used to compile program to realize the load of moving heat source,and realize the simulation of laser welding with multi-step loops to get the temperature field distribution.From the simulation result,we can find the temperature field of laser welding process distributed in a elliptical area,and semi-stable temperature field formed on the weld part.Difference exists between the temperature field of thin and thick board.The temperature field range of thin board is lager,and the melting pool dimension is larger than thick board.The melting range is larger than thick board also.This result has a certain reference value and can guide the research of material performance changing in the laser machining process.