| 摘要 |
PURPOSE:To increase the wear resistance of a piston-ring groove, by forming a hard layer by casting a molded material consisting of a wear-resistant metal over the inner surface of the piston-ring groove. CONSTITUTION:A piston 11 is used in a reciprocating internal combustion engine and it is made, for instance, of 1/2 molybdenum cast steel. According to the present invention, a hard layer 13 is formed over the inner surface of the top piston-ring groove 12 by casting a molded material consisting of a wear- resistant material such as sintered stellite or cemented carbide. By forming such a hard layer, it is enabled to decrease the wear rate of the piston-ring groove at its upper and lower surfaces against beating and scratching applied to them due to deformation, vibration, etc. of the piston ring fitted in the groove. Thus, the wear resistance of the piston-ring groove 12 can be increased. |
