PISTON RING, PISTON, CYLINDER AND PISTON PIN HAVING AMORPHOUS AND HARD CARBON FILM

摘要

This is to provide a piston ring, a piston, a cylinder and a piston pin, which can realize low friction coefficient without depending on the adsorption or reactions of additives, which are included in lubricating oils, when being employed under wet condition using lubricating oil. This is to construct a piston ring, a piston, a cylinder and a piston pin, which are employed under wet condition using lubricating oil, so as to be equipped with an amorphous hard carbon film, whose Si content is 1 atomic % or more and 20 atomic % or less and whose surface roughness is Rzjis 0.5 µm or less, respectively.