Finite element visualization of fatigue crack closure in plane stress and plane strain

The fatigue crack closure phenomenon in plane stress and plane strain was investigated using elastic-plastic finite element simulations of growing fatigue cracks in both the plane stress and plane strain. The residual stress and strain fields near the crack tip were depicted by both the color fringe plots and the x-y graphs. It was found that the development of the residual plastic stretch in the wake of a growing plane stress fatigue crack is associated with the transfer of material from the thickness direction to the axial direction. Results of finite element analysis of a growing fatigue crack indicate that crack closure does occur under a pure plane strain condition. (I.S.)