Evaluation of surface fatigue strength based on surface temperature (Surface temperature calculation for rolling-sliding contact)

Surface temperature is considered to be an integrated index that is depende nt on not only the load and the dimensions at the contact point but also th e sliding velocity, rolling velocity, surface roughness, and lubrication co nditions. Therefore, the surface durability of rollers and gears can be eva luated more exactly and simply by the use of surface temperature rather tha n Hertzian stress. In this research, surface temperatures of rollers under different rolling and sliding conditions are measured using a thermocouple. The effects of load P, mean velocity V-m and sliding velocity V-s on surfa ce temperature are clarified. An experimental formula, which expresses the linear relationship between surface temperature and the (PVsVm-0.83)-V-0.96 -V-1.31 value, is used to determine surface temperature. By comparing calcu lated and measured temperature on the tooth surface of a gear, this formula is confirmed to be applicable for gear tooth surface temperature calculati on.