Tribological Characteristics of End Faces with Diamond Macro-pores Textured under Lubrication

The UMT-3 multifunctional friction and wear testing machine and homemade wear test rig were applied, in order to examine the size, shape, configuration and depth of the diamond macro-pores on the influence law of the friction coefficient and mechanism analysis. An end face with the diamond macro-pores texture of the proper structure and depth greatly improved the tribological properties of the lubricated friction pairs.End faces with bi-direction, doublerow inclined diamond macro-pores (the depth was 10 μm) had good tribological properties. In the hydrodynamic lubrication regime, with the increase of the Herscy characteristic number, fluctuated friction coefficient rather than a gradually increasing friction coefficient was observed. Because fluid between the sliding surfaces produced cavitation, the gas-liquid boundary of cavitation region produced interfacial slip and increased the area of cavitation region. As a result, the increasing slip length increased the interface slip effect, and hence reduced friction coefficient.