Effect of Load on High Temperature Dry Friction Characteristics of Cr4Mo4V Bearing Steel

In order to explore the wear mechanism of Cr4Mo4V bearing steel under the condition of instantaneous dry friction， the silicon nitride ball and Cr4Mo4V steel disc friction pair were used to explore the influence of load changes on the friction characteristics of Cr4Mo4V bearing steel under the conditions of an ambient temperature of 300 ℃， a speed of 0.3 m/s and a sliding dry friction. Results showed that when the load increased in the range of 1.2～2.4 GPa，the friction coefficient of Cr4Mo4V bearing steel decreased from 0.89 to 0.42，while the wear rate increased from 2.05×10-6 mm3/(N·m) to 2.68×10-6 mm3/(N·m). Oxidation reaction occurred on the worn surface， and the types of oxides produced under different load conditions were different. Besides， the main wear mechanisms of Cr4Mo4V were oxidation wear and adhesion wear.