| 摘要 |
In the present invention, in order to provide a piston ring covered with an amorphous hard carbon film that has low friction characteristics and outstanding abrasion resistance and film peeling resistance in order to achieve lower fuel consumption in an automobile, the outer peripheral surface of a steel piston ring base material is covered with a non-crystalline hard carbon film with a thickness of 0.4-20 µm, with the following interposed therebetween: a base layer that comprises a CrN/Cr layered film or CrN/TiN layered film with a thickness of 10-60 µm, in which CrN-type chromium nitride and chromium metal or TiN-type titanium nitride are layered alternately; and an intermediate layer that comprises chromium metal and/or titanium metal and has a thickness of 0.05-1.0 µm. |
