Germanium containing coating for inner surfaces of cylinder liners

摘要

A cylinder liner (20) comprises a substrate (24) and a germanium containing coating (22), typically a diamond-like carbon (DLC) coating applied by a vapor deposition technique. The coating (22) may include a base layer (36), an intermediate layer (38), and a protective layer (40), each having a graded composition. The base layer (36) comprises, in weight percent (wt. %) of the base layer (36), 50.0 to 70.0 wt. % carbon, 30.0 to 50.0 wt. % silicon, and not greater than 20.0 wt. % germanium. The intermediate layer (38) comprises, in weight percent (wt. %) of the intermediate layer (38), 40.0 to 60.0 wt. % carbon, 15.0 to 35.0 wt. % silicon, and 15.0 to 35.0 wt. % germanium. The protective layer (40) includes, in weight percent (wt. %) of the protective layer (38), at least 90.0 wt. % carbon.

主权项

1. A cylinder liner (20), comprising:
a substrate (24) including an inner surface (26) extending around a center axis (A); a coating (22) disposed on said inner surface (26) of said substrate (24); said coating (22) including an intermediate layer (38), said intermediate layer (38) comprising, in weight percent (wt. %) of said intermediate layer (38), 40.0 to 60.0 wt. % carbon, 15.0 to 35.0 wt. % silicon, and 15.0 to 35.0 wt. % germanium; and said coating (22) including a protective layer (40), said protective layer (40) including, in weight percent (wt. %) of said protective layer (38), at least 90.0 wt. % carbon, wherein the weight of said layers (38, 40) does not include the weight of any hydrogen present in said layers (38, 40).