Subsurface crack investigation on delaminated ceramic elements

Abstract

This paper presents an experimental investigation of subsurface cracks on delamination fatigue failure of ceramic rolling elements. Three failure cases are considered on hot isostatically pressed silicon nitride surfaces. These cases consist of two failures from ceramic/ceramic contact and one from pre-cracked ceramic/bearing steel contact. The extent of subsurface crack length and depth is investigated using a dye penetration method and acoustic microscopy. Quantitative measurements of subsurface crack shapes, depths and lenghts are presented. The information from this study relates to the fatigue failure modes.