Effect of non-metallic inclusions on fatigue life of high-speed railway bearings

Abstract

In the process of smelting and manufacturing of high-speed bearing steel, non-metallic inclusions are always inevitable, which destroy the continuity of the metal matrix and decrease the fatigue life of high-speed railway bearings seriously. Under the condition of obtaining the position and the number of the maximum contact load of the high-speed railway bearings, according to the Hertz contact theory, the maximum contact stress σmax between the roller and the raceway of the high-speed railway bearings and the half-width b of the contact surface is calculated, and then the stress distribution equation of the contact surface is obtained. According to the basic theory of fatigue life, the local stress-strain method was used to analyse the influence of the distance, depth and quantity between the inclusions contained in the raceway of the outer ring on the contact surface stress and the fatigue life of the high-speed railway bearings. Quantitative relationship between the influence of non-metallic inclusions and the contact fatigue life of high-speed railway bearings was determined, which provided scientific bases in the smelting process of high-speed railway bearing steel.