Coated piston ring having a protective layer
AssigneeFederal-Mogul Burscheid GmbH
InventorPETER-KLAUS ESSER
Life of this patent
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Abstract
A piston ring is provided with is furnished with a diamond-like carbon (DLC) layer as a functional/wear protection layer, wherein the DLC layer is covered with a protective layer, the material of which differs from that of the DLC layer, and the material of which has higher thermal resistance that the material of the DLC layer. In addition, a method is provided for producing a piston ring with a DLC wear protection layer, in whose surface the protective layer is present in the form of deposits in depressions created by the surface roughness.
Claims21
1-19. (canceled)
A piston ring, comprising a piston ring body,
- wherein a DLC layer is applied to the outer surface of the piston ring body, at least to a bearing surface of said outer surface, as a functional coating,
- wherein a protective layer is applied over the functional coating at least on partial surfaces of the piston ring bearing surface,
- wherein the protective layer consists of a material which is different from the material of the functional coating and has greater thermal resistance that the functional coating material,
- wherein the protective layer is present in the form of surface deposits in recesses in the functional coating.
A method for producing a coated piston ring, comprising
- providing a piston ring body;
- applying a DLC layer as a functional coating at least to a bearing surface of the piston ring body;
- applying a protective layer over the functional coating;
- partially removing the protective layer, so that only deposits are left in depressions in the surface of the functional coating.
Dependencies are inferred from the claim text.