LUBRICATED PART HAVING PARTIAL HARD COATING ALLOWING REDUCED AMOUNTS OF ANTIWEAR ADDITIVE

摘要

A lubricated part composition containing (a) a part with at least a partial hard surface coating of average thickness less than about 25 micrometres, said coating containing at least one moiety selected from the group consisting of silicides, nitrides, carbides, borides, oxides, sulphides and mixtures thereof; (b) a detergent selected from at least one of the group consisting of a phenate salt, a sulphonate salt, a salixarate salt and mixtures thereof; and (c) an oil of lubricating viscosity. The invention further relates to the use of the composition to decrease engine wear, decrease sludge formation, filter plugging, decrease sulphur emissions and decrease phosphorus emissions.