COMPOSITE CHROMIUM PLATING FILM, AND SLIDING MEMBER EQUIPPED WITH THE FILM

摘要

[Problem] To provide a piston ring product in which hard particles can be uniformly filled into cracks occurring on a hard chromium plate that is applied on a sliding surface and which has excellent long-term stability. [Solution] Provided is a composite chromium plating film, in which a hard chromium plating film has a crack-like groove formed thereon and hard particles are filled into the groove, and which is characterized in that the hard particles to be used are irregular particles having the following powder characteristic properties: an average circularity degree of 0.70-0.85; an average equivalent circle diameter of 6.0 µm or less; and an aspect ratio of 1.3 or more. The composite chromium plating film is applicable onto a sliding surface of a piston ring product.