外拘束条件下的不锈钢焊接残余应力变化规律

Variation of external constrain conditions on stainless steel welding residual stress

为了探究外拘束条件下不锈钢焊接接头残余应力的分布规律,采用三维热弹塑性有限单元法,对不同拘束条件下的不锈钢焊接过程进行了分析。结果显示,施加不同的拘束条件,平板试样焊后焊接结构的残余应力大小和分布不同。约束底面四点的拘束条件能较好地模拟平板在自由状态下的焊接情况,约束焊接件侧面将显著增大焊接结构的残余应力,通过统一夹具垫板与焊接件为多体耦合模型,发现完全可以反映平板焊接过程中夹具与被焊件的相互作用并有效减小残余应力。

In order to investigate the residual stress distribution of the stainless steel welded joints under the external constraint conditions,use of three-dimensional thermal elastic-plastic finite element method,the stainless steel welding process under the conditions of different binding were analyzed. The results showed that the size and distribution of welded structures of the sample are different after applying different binding conditions. The constraint conditions of four points at the bottom was capable to simulate the binding plate welding in the free state condition, the welding residual stresses welding will significantly increase if constraint the side of the welded structure, through a unified fixture plate and welding parts for the multi-body coupling model will found it can truly jig plate welding process interactions with the welders and effectively reduce the residual stress.