分段焊的焊接顺序对T形接头残余应力场的影响

Influence of welding sequence of subsection welding on residual stress of T joint

在利用单元死活技术以及椭球形移动热源模型分析T形接头焊接温度场的基础上,利用数值模拟的方法研究了分段焊的焊接顺序对T形接头焊接残余应力场的影响。结果表明,分段焊不仅可以增加焊缝整体的残余低应力的区域,而且采用先焊两端后焊中间的方法可以有效地降低先焊区域的焊接残余拉应力。对于先焊焊段上的某点来说,到中间焊段两端的距离越小,焊接残余应力的降低效果越明显;中间焊段的收弧区降低先焊焊段残余拉应力的效果要优于起弧区。

By element unactive technology and ellipsoidal heat souce,temperature field of T joint in subsection welding was analyzed and then the influence of welding sequence on welding residual stress of T joint was studied by numerical simulation.The results show that the subsection welding not only increases the low residual stress region of the whole welding seam,but also effectively decrease the stress peak of some region in welding seam with reasonable welding sequence and welding direction.For the prior welding subsection,the shorter distance to the latter welding subsection,the better effect for decreasing welding residual stress.Moreover,the effect of the latter welding subsection's quenching arc region on decreasing residual stress of the prior welding subsection is better than the striking arc region.