| 摘要 |
A piston ring 30 is made of a nonferrous metal having a Young's modulus of 15000 kgf/mm<2> or less and a tensile strength of 100 kgf/mm<2> or more. such as a titanium or copper beryllium alloy. A hard surface layer 32, is formed on at least an outer peripheral surface. In preferred embodiments at least an outer peripheral surface and upper and lower surfaces 17, 18 thereof are formed with a nitrogen diffused layer 32, and at least an outer peripheral sliding surface thereof is coated with a hard film by physical vapor deposition on the nitrogen diffused layer 32; 15A. <IMAGE>
|
