激光焊接1Cr17铁素体不锈钢温度场数值模拟

Numerical Simulation of Temperature Field of Laser Welding 1Cr17 Ferrite Stainless Steel

采用SYSWELD有限元软件,建立了激光焊接铁素体不锈钢的3D有限元模型。考虑材料的热物性参数与温度的非线性关系以及表面对流和辐射热交换的影响,分析了激光焊接过程中温度场的分布及焊缝表面不同点的热循环变化,并进行了实验验证。结果表明:焊接一段时间后,焊接温度场呈现准稳定状态,随焊接热源的继续移动,焊缝区各点的温度基本保持稳定。沿着焊接方向,焊缝表面不同节点Tmax-T800和T800-T300冷却速度逐渐降低。另外,焊缝熔池的模拟结果和相同工艺参数的实验结果相吻合,证明了焊接过程中数学模型建立的合理性,模拟结果为铁素体不锈钢焊接过程的优化提供了理论依据。

The 3D finite element model of laser welding ferrite stainless steel is established by SYSWELD finite element software.Considering the non-linear relation between the thermo-hysical parameters,the effects of surface convection and radiation heat transfer,temperature field distribution and thermal cycle change at different nodes on weld seam surface during laser welding are analysed,which is verified by experiment.The results show that after welding for a period of time,the welding temperature field is in a quasi-stable state,the temperature at each point of welding zone basically retains stable as the continuous movement of welding heat source.The cooling rate of Tmax-T800 and T800-T300 at different nodes on welding seam gradually decreases along welding direction.In addition,the simulation results of weld seam pool agree with the experimental results of the same process parameters,which proves the establishment rationality of mathematical model for welding process,and provides the theoretical basis for optimizing the welding process of ferrite stainless steel.