Abstract
Compressive residual stress is considered to be useful for arresting of fatigue crack propagation in welds, composite metals and case hardened metals. However, there are few reports on the quantitative relation between the distribution of residual stress and fatigue crack propagation.
In this study, homogeneous thin plates which had mainly longitudinal compressive residual stress around crack were made by water quenching from relatively low temperatures below 723°C. In fatigue tests, the compressive residual stress around crack was confirmed to be an important factor controlling the fatigue crack propagation. This influence was quantitatively discussed by using a linear fracture mechanics model. The effective stress intensity factor range calculated by this model was useful for understanding of the fatigue crack propagation in cracked specimens. This analysis also was applied for the fatigue crack propagation through compressive residual stress field in the plate composed of low carbon steel and midium carbon steel. The results of this study suggest that not only the defect size but also the residual stress field have to be discussed for evaluation of defects detected by nondestructive methods.
