奥氏体不锈钢单层焊与多层焊残余应力数值分析

Welding residual stress of single-layer and multi-layer welding of austenitic stainless steel by FEM

基于SYSWELD有限元模拟技术,模拟奥氏体不锈钢对接接头单道单层焊和单道多层焊2种焊接工艺下的焊接残余应力场分布。单层焊采用大电流熔化极惰性气体保护焊,多层焊第1层采用钨极氩弧焊,中间层和表面层采用焊条电弧焊,同时对结果进行分析比较。结果发现:单道多层焊比单道单层大电流焊焊接效果好,焊接残余应力最大值分布区域更小,因为多层焊的焊接电流小,焊接层次增加使得热输入小,造成受热范围减小,同时后层焊缝对前层焊缝具有热处理的作用,因而改善了残余应力和焊接接头组织。研究方法和研究结果为对接接头的残余应力预测和焊接质量控制提供参考。

Based on SYSWELD finite element simulation technology, the welding residual stress field distribution of single-layer welding and multi-layer welding were simulated. The large current MIG welding was applied in singlelayer welding. The gas tungsten arc welding was used in the first layer, shielded metal arc welding in interlayer and surface layer. The result of the comparative study of the numerical analysis indicated that the effect of multi-layer welding was better than single-layer welding, the maximum value distribution regional of welding residual stress was smaller. For the current of multi-layer welding was lower, then the heat range was smaller, thus the welding residual stress and the welded joint were improved. Such research methods and results would provide reference for the prediction of welding residual stress and welding quality control.