焊接接头韧度CTOD评定的适用性与允许值研究

EXPLORATION ON APPLICABILITY AND ACCEPTABLE VALUES IN CTOD TOUGHNESS EVALUATION FOR WELDED JOINTS

对厚钢板两种焊接工艺焊接接头中的焊缝材料和热影响区材料进行拉伸试验。发现各自的拉伸曲线都可视为理想弹塑性,符合Wells提出裂纹尖端张开位移(cracktipopeningdisplacement,CTOD)理论的假设条件。因此,证明CTOD试验评定焊接接头韧度的适用性。提出确定钢结构焊接接头CTOD允许值的“母材参考法”和“类比法”,为在钢结构的设计和建造中合理地确定焊接接头韧度指标提供方法。

The tension tests have been conducted for the materials of welding centre and heat affected zone, which come from welded joints in thick steel plate under two welding crafts. The tension curves of these materials are all belong to ideal elastic-plasticity. Hence the mechanical properties for materials of welded joints conform with the assumption of CTOD （crack tip opening displacement） theory developed by Wells. So the applicability of evaluating the toughness of welded joint with CTOD test has been verified. Two methods, the ＂Parental Metal-Method＂ and ＂Analogy-Meth~＂, have been developed for determining the acceptable value of CTOD in steel structure,and these two methods can be used to determine the index of toughness of welded joints reasonably in design and fabrication of steel structures.