Friction of some commercial polymer-based bearing materials against steel

Abstract A tri-pin-on-disc tribometer has been used to determine coefficients of friction, μ, given by some polymer-based bearing materials sliding on mild steel over a wide range of loads and speeds, both dry and lubricated. At constant sliding speed, values of μ for both the dry and lubricated polymers were virtually independent of load over the range (moderate to heavy) used. The frictional properties are thus presented in terms of the variation of μ with sliding speed, these values being representative of all but lightly loaded applications. Under unlubricated conditions the plastics tested varied considerably in performance, the lowest friction being obtained with a filled polyethene and the highest with a polyurethane. Paraffin oil lubrication significantly reduced friction in all cases