Plastic deformation zones kinetics during fatigue fracture

The structures of the plastic deformation zones under the fatugue fracture surface of the aluminum alloy 1161 and structural 38Kh3MA steel were investigated using the X-ray fractography method. It is shown that plastic deformation zone structure is subjected to substantial changes when the fatigue fracture develops. The dustribution of deformations allong fracture depth in specimens tested at the values of stress intensity factors scope 12.5; 15.5 and 19.0 MPa&middot√m had been illustrated. General characteristics and peculiarities of plastic deformation zones formation under fatigue loading, depending in materials structure and type of testing are considered.