ANALYSIS OF RING CRACKS IN CERAMIC ROLLING ELEMENTS USING THE BOUNDARY ELEMENT METHOD

摘要

Ceramic materials have been increasingly used in bearing systems for over a dozen years. This is due to the specific properties of ceramic materials, such as high hardness, corrosion resistance, the possibility of use in aggressive chemical environments, as well as due to the lower specific weight as compared to steel materials. However, the use of ceramic materials imposes many limitations. The main disadvantages include surface cracks and a low fracture toughness value. The paper presents a numerical analysis of crack propagation in silicon nitride balls. The directions of propagation were analysed for the cracks that are most commonly found on the surface of the commercially available ceramic balls. The directions were analysed along the crack front and considering the location of the crack in relation to the contact point of the balls in the rolling contact. The numerical calculations are based on a three-dimensional model of the ring crack. Numerical calculations were carried out using the boundary element method. Numerical solutions were compared with the results of experimental research.