超高强钢板多层多道焊温度场有限元分析

Finite element analysis of temperature field in multi- pass welding of ultra high strength steel plate

针对616超高强钢板焊接出现裂纹等问题,为优化焊接工艺参数,准确提供焊接条件下的温度场,采用Sysweld软件建立了15 mm厚板脉冲MIG多层多道焊有限元分析模型,对多道焊焊缝及热影响区形状尺寸进行计算,并分析比较模拟结果。结果表明,有效热输入功率为3 600 W时,校核热源熔融最佳;距热源最近的特征点温度变化最迅速,最先升到峰值点,高温驻留时间最长;道间温度伴随焊接道次增多而逐步上升,控制道间温度可预防热影响区晶粒粗大,有助于改善接头组织。

Considering the cracks problem in the welding of 616 ultra- high strength steel, the finite element model for 15mm thick muhi - pass wehting of pulse MIG was developed to optimize the welding parameters and provide the temperature fieht accurately. The shapes and sizes of muhi - pass welding bead and HAZ were simulated by SYSWELD software, in addition, the simulation results were analyzed and compared. The results show that the checked heat source melts the best when effective thermal input power is 3600W. The feature point which is nearest to heat source firstly rises to the peak point with the longest high - temperature dwell time, and its temperature changes the most rapidly. With the weld passes increasing, the interpass temperature rises gradually. The proper interpass temperature could prevent coarse grains in HAZ, which helps to improve joint organization.