The critical condition for the transition from HL to ML in water-lubricated SiC

Silicon carbide (SiC) with water lubrication is being considered as the most promising combination to replace metals and oil for sliding bearings and mechanical seals of machines working in water. The basic properties of the Stribeck curves of water lubricated SiC in parallel contact, especially, the critical conditions for the transition train HL to ML were studied experimentally. The hydrodynamic lubrication regions and minimum friction coefficients of metal pair in oil and SiC pair in water are compared to give a quantitative value or the oil viscosity range, in which metal/oil can be directly replaced by SiC/water for triboelements. In order to improve the load-carrying capacity of SiC sliding bearings for the increasing strict demands from industry, a surface texture was introduced to one of the contact surfaces by means of reactive-ion etching. The effect of surface texture on the lubrication regimes and the minimum friction coefficient were evaluated experimentally.