溶接部に存在する表面き裂の安定成長試験

抄録

The behavior of a surface crack crossing the fusion line is studied experimentally and numerically. By changing the aspect ratio of the surface crack, three kinds of surface-cracked specimens are tested. The distributions of Δa, CTOD and CTOA values along the crack front are measured. The experimental results show that the distribution patterns of these parameters along the crack front across the fusion line are not largely different from those of homogeneous specimens. Significant differences in CTOA values between the base metal and weld metal are recognized. By referring to the basic material test, three-dimensional FEM analyses are carried out. The effect of the fusion line on the J-integral distribution and CTOD are obtained and are compared with experimental results. The crack tip fields are compared with HRR solutions. It is found that the existence of the fusion line has no significant effect on the crack tip field.