In order to study the mixed lubrication performance of the pin-chain plate contact pair for the silent chain,the geometric relation and kinetic characteristics of the pin-chain plate contact pair were analyzed,and a thermal mixed lubrication model of a pin-chain plate contact pair was established based on the average flow model.Effects of equivalent curvature radius,surface roughness and load on the non-Newtonian thermal mixed lubrication performance were discussed.The results show that, with the increase in the equivalent curvature radius,the film thickness ratio increases,the lubrication state is changed from mixed lubrication to full film lubrication,the oil film pressure increases and the asperities contact pressure decreases,and the friction coefficient and friction thermal decrease.As a result,the lubrication performance of the pin-chain plate pair will improve.However,due to the diameter deviation between the pin shaft and the chain plate,the equivalent curvature radius varies in a certain range.Therefore,the influence on the lubrication performance of the pin-chain plate contact pair is random.With the increase of surface roughness and the load,the film thickness ratio decreases and friction thermal increases,the lubrication state changes from full film lubrication to mixed lubrication,which will cause wear risk of the pin-chain plate pair.