水环境中异种钢焊接过程数值模拟

Numerical Simulation on Welding Process of Dissimilar Steels Welding in Water Environment

利用SYSWELD有限元软件、采用双椭球热源模型,模拟了Q345/304异种钢平板焊接在空气环境和水环境中的焊接过程温度场和残余应力场,得到了不同时刻水环境和空气环境中工件的焊接温度场分布和节点的温度变化曲线、试件冷却后的焊接线残余应力场分布曲线。对比分析了异种钢焊接在水环境与空气环境中的差异。模拟结果表明,不论在水环境还是在空气环境中不锈钢一侧的加热速度和散热速度都要小于低合金钢一侧,水环境中焊接试件的焊接线上的热循环曲线覆盖面积明显比空气环境中的试件小,焊接线上的残余应力要大于空气环境中的焊接试件。

The welding temperature field and residual stress field of Q345 / 304 dissimilar steel welding in air and water environment were simulated by SYSWELD finite element software and double ellipsoid heat source model. The workpiece welding temperature field distribution and node temperature curve at different time in water and air environment were obtained. the welding wire residual stress distribution curve after specimens cooling was also obtained. The differences of dissimilar steel welding in water and air environment were analyzed. The simulation turns out that the heating rate and cooling rate of stainless steel side are less than that of low-alloy steel both in water and air environment, the area covered by welding thermal cycle curve in water environment is much smaller than that in air environment as well as the residual stress in water environment is greater than that in air environment.