PISTON RING AND PROCESS FOR THE MANUFACTURE THEREOF

摘要

A piston ring for a piston of an internal combustion engine may include a body composed of a ferrous material. The body may have an upper portion, a lower portion opposed to the upper portion, an internal portion configured to face towards a piston groove and an external portion opposed to the internal portion. An upper chamfer may be disposed between the upper portion and the external portion. A lower chamfer may be disposed between the lower portion and the external portion. The upper portion, the lower portion and the internal portion may each have a nitrided layer. The external portion, the upper chamfer and the lower chamfer may include at least one ion plated coating layer. The nitrided portion in at least a superficial layer may have a hardness of 700 HV or less.

主权项

1. A piston ring for a piston of an internal combustion engine, comprising:
a body composed of a ferrous material, the body defining an upper portion facing towards a piston head, a lower opposed portion facing towards a piston skirt, an internal portion facing towards a piston groove, and an external opposed portion configured to slide against a cylinder wall or liner, wherein the upper portion and the external portion are disposed essentially mutually orthogonal and define an upper chamfer, and the lower portion and the external portions are disposed essentially mutually orthogonal and define a lower chamfer, wherein the upper portion, the lower portion and the internal portions each have a nitrided portion, and the external portion, the upper chamfer and the lower chamfer are not nitrided and include at least one ion plated coating layer, and wherein the nitrided portion in at least a superficial layer has a hardness of 700 HV or less.