Interaction between Propagating Crack and Two-or Three-Dimensional Macrodefect

Abstract

The effect of a two- or three-dimensional platelike defect on the crack propagation behavior of fatigue or delayed failure was examined, and the results were analyzed by using the single large dislocation model.
The three-dimensional platelike defect which lies on the same plane as that of the main crack accelerates the propagation of the main crack, while the one which lies perpendicular to the main crack decelerates the propagation of the main crack. The platelike defect lying with an angle of 45° against the plane of the main crack slightly increases the crack propagation velocity and makes the twist and step on the crack propagation path.
The interaction behavior between a propagating crack and a two-dimensional or three-dimensional defect can be explained qualitatively by the single large dislocation model.