激光焊接熔池特性的三维数值模拟-《郑州大学学报(工学版)》

文章信息/Info

Title:: Three Dimensional Numerical Simulation of Characteristics of Laser Welding Pool

Author(s):: MEI Lifang; CHEN Youhai; YAN Dongbing; GE Xiaohong; WANG Junqi; Department of Mechanical and Automotive Engineering，Xiamen University of Technology，Xiamen 361024，China

Keywords:: laser technology; welding; weld pool shape; temperature; numerical simulation

摘要:: 为了对激光深熔焊接熔池特性进行三维解析模拟，基于一定的基本假设条件将焊接过程视为准稳态过程,应用激光焊接低碳钢熔池形状和温度分布的三维控制数学模型,以求解相态转变界面为基础,将对激光深熔焊接熔池特性的模拟简化为对气–液相界面和固–液相界面位置和温度分布的积分方程的求解,得出了焊接试样上的熔池几何形状和温度分布情况.结果表明:熔池形状相对光轴中心向后偏移,且熔池前沿壁陡峭,后沿壁过渡平滑;熔池深度和宽度随着激光功率的增大同步增大,随焊接速度的增加同步减小,随光斑尺寸增大熔宽增大而熔深减小;熔池各层面上的最高温度点均偏后于光束中心,等温线分布密集表明激光焊接热影响区窄.

Abstract:: For simulating the characteristics of laser deep penetration welding pool in three-dimensional,thewelding process was regarded as quasi-steady-state under a certain assumptions, and the mathematical modelsof pool shape and temperature distribution for laser welding low carbon were applied to solve the phase trans-formation interface. The mathematical simulations of laser welding pool shape and temperature filed were sim-plified to solve the integral equation of gas / liquid interface and solid / liquid interface. Then,the character-istics of weld pool shape were obtained.The results show that ,for laser weld pool,the lowest point lagged be-hind the optical axis center,the front wall gradient was steep,and the wear wall gradient was smooth. Theweld pool depth and width both increased with the increase of laser power,and decreased with the increase ofwelding speed. As laser spot radius increases,the weld pool depth increases，and the weld pool width decrea-ses. The highest temperature on the surface of weld pool also lagged behind the optical axis center,and the i-sothermals distributed dense which would indicate a narrow heat-affected zone.