PISTON RING AND MANUFACTURING METHOD THEREFOR

摘要

The present invention addresses the problem of providing a piston ring having a hard carbon film exhibiting exceptional wear resistance and running-in property, and a manufacturing method therefor. This problem is solved by a piston ring (10) having a hard carbon film (4) formed on at least an external peripheral sliding surface (11) of a piston ring base material (1), the hard carbon film (4) having an sp 2 component ratio within a range of 40% to 80% inclusive as measured by a TEM-EELS spectrum which combines electron energy loss spectroscopy (EELS) with a transmission electron microscope (TEM), a hydrogen content being in a range of 0.1 at.% to 5 at.% inclusive, and an amount of macroparticles appearing on the surface being within a range of 0.1% to 10% inclusive by area ratio. The hard carbon film (4) is formed on a hard carbon foundation film (3) formed under low-speed film-forming conditions on the side of the piston ring base material (1), and the hard carbon foundation film (3) is formed with an arc current value 80% or less of the arc current value during the formation of the hard carbon film (4).