Study of rolling contact fatigue of bearing steels in relation to various oxide inclusions

Flaking failure of rolling contact fatigue is known to originate from non-metallic inclusions, where fatigue cracks occur at subsurface region of materials. It is fundamental to understand the main factors governing the rolling contact fatigue life. Steel samples with different size and chemical composition of oxide inclusions were evaluated on rolling contact fatigue life. As a result,(i)Rolling contact fatigue life was improved by reducing the oxide size.(ii)Rolling contact fatigue life varied depending on the oxides composition.It has been concluded that the chemical composition of the inclusions is an important factor of the rolling contact fatigue life, in addition to the inclusion size.