过载拉伸对焊接接头应力集中区域力学行为的影响

Influences of over load tension on the machanical behaviors of stressconcentration areas of welded joint

本文以弹塑性有限元为基础,建立了过载拉伸对焊接接头应力集中区域的力学数值计算模型,得出了在不同载荷下板材的应力集中区域的应力分布情况,单元屈服以及卸载后的残余应力分布情况。结果表明:过载拉伸时,在应力集中处会首先发生屈服,并伴有一定的拉伸塑性变形;卸载后,在构件中会产生由于不均匀塑性变形引起的残余应力,在应力集中处发生拉伸塑性变形的区域将产生压缩应力,该压缩应力对结构是有益的。

The stress field of stress concentration areas of welded joint are calculated by elastic-plastic finite element method, the stress distribution of stress concentration areas, elements yielded and the residual stress distribution are obtained. The result shows that the elements trend to yield and have plastic distortion first when the load is exerted. When the load is removed, there will be residual stress in these elements and the stress is pressure stress, which is beneficial to the welded joint.