Contact Fatigue of Carbon Steel Gear Under Different Lubrication Conditions

ABSTRACT The contact fatigue of carbon steel gear tooth surfaces under different lubrication conditions has been investigated and a model of the effect of lubrication conditions on contact fatigue has been established. Micro damage less than Hertzian contact is more likely to expand into macro pitting. The pressure around the micro damage increases when the micro damage partially coincides with the contact width, so the tooth surface around the pit is more likely to produce new pits, and then forms the superposition and aggregation. The larger the lubricating oil supply, the larger the contact width, and the larger the width of the micro damage that can be activated, the improvement of lubrication can promote the propagation of micro damage.