Critical Sizes of Different Types of Inclusions under Rolling Contact FatigueLoad

摘要

A finite element study was performed of driving forces of short cracks atinclusiions in bearing steel exposed to rolling contact load. Five inclusion configurations were considered, namely a pore, a manganese sulfide inclusion, a through-cracked alumina inclusion, an alumina inclusion which was uncracked but which could debond from the matrix and finally a titanium nitride inclusion. The inclusions were situated at A depth corresponding to the shear stress maximum of the Hertzian stress field. Short cracks were allowed to grow from the inclusions on a plane inclined to the race way. The driving forces of the cracks were evaluated in terms of energy release rates.