Plastic deformation around fatigue cracks

Abstract

The formation of a plastic deformation zone with fatigue crack propagation was observed and analyzed with surface roughness and etch-pit techniques on a macro scale. Both techniques were calibrated with respect to plastic strain in order to characterize the strain distribution within the plastic zone. Side surfaces and interior longitudinal and transverse cross-sections were evaluated. The crack growth kinetics were correlated with the evolutional characteristics of the plastic zone.