非等强焊接接头的屈服载荷

焊接接头热影响区软化是TMCP钢不可避免的问题.为分析这种接头的承载能力,利用滑移线场的变形机制,考虑焊缝和热影响区的强度相对于母材的变化,以及它们的宽度相对于板厚的变化,给出了包含有焊缝、热影响区和母材的拉伸试样屈服载荷的计算方法.计算结果表明,热影响区的硬化或软化及其宽度对接头屈服载荷有直接的影响.热影响区软化的焊接接头承载能力可以通过提高焊缝强度来补偿.该分析方法适于TMCP钢焊接接头焊缝强度的初步设计.

Limit load of welded joint with mismatched mechanical strength

The softening in HAZ(heat affected zone) of welded joint is inevitable with the welding of TMCP steels. Employing the deformatim mechanism of slip line field, the load bearing capability of such joint is analyzed in terms of strength variation of the weld as well as the HAZ with respect to different matrices, and width variation of those with different thickness of the welded plate as well, resulting in a method for evaluation of the limit load bearable by a tensile specimen composed of the weld, HAZ, and the matrix. An evaluation result with this method shows that the limit load is directly affected by the hardening or softening in the HAZ of the joint as well as by the width of HAZ. The decrease of limit load of welded joint due to the softening in HAZ can be compensated with improving the weld strength. This analysis method is suitable for preliminary design of weld strength of the welded joint of TMCP steels.