Experimental Study on Stribeck Curves Based on Characteristic Roughness

To research the influence of surface roughness on Stribeck curves, the variation of friction coefficient was investigated based on the frictional pairs of stainless steel pins with different surface roughness and 45# steel disc under oil-immersed condition. The results showed that, the rougher the surface, the bigger the mixed lubrication area on Stribeck curve and the smaller the slope of the curve, which led to the non-uniqueness of the experimental model of friction coefficient for different surface roughness. Thus, the characteristic roughness, which was derived from fractal parameter, was adopted to be taken as the rough surfaces and was pulled into the Stribeck hydrodynamic parameter to create a new hydrodynamic parameter. Under the new hydrodynamic parameter, the Stribeck curves of frictional pairs with different surface roughness had a good consistency and can be used to determine the experimental model of friction coefficient which was independent of the surface roughness.