Numerical studies of fatigue crack growth by the crack-tip blunting and re-sharpening mechanism

摘要

Crack-tip blunting and subsequent re-sharpening during a load cycle is a basic mechanisms for fatigue crack growth in ductile metals. Based on an elastic-perfectly plastic material model, crack growth computations have been continued up to 700 full cycles by using remeshing at several stages of the plastic deformation. The method has also been used to study the effect of overloads or of compressive underloads. The influence of mesh refinement has been used to study the possibility that striations could be predicted, but even with much refined meshes no indication of crack surface folding has been found.