Combination of cylinder and piston ring
US9644738B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2013 |
| Grant date | May 9, 2017 |
| Priority date | — |
| Expiry date | May 28, 2034 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF05C2251/10
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
To provide a combination of a cylinder made of a hypereutectic Al—Si alloy and a hard-carbon-coated piston ring both exhibiting excellent wear resistance, the piston ring is provided with a laminate coating at least on an outer peripheral sliding surface thereof; the laminate coating comprising a metal layer, a metal-containing, hard carbon layer, and a metal-free, hard carbon layer in this order from the substrate side; the laminate coating having Martens' hardness (indentation hardness) HMs of 5-13 GPa, indentation modulus E of 70-200 GPa, and a deformation ratio Rpe of 0.45 or less, which is expressed by a ratio (Wp/We) of plastic deformation energy Wp to elastic deformation energy We; and a ratio (Tmf/Tm) of the thickness Tmf of the metal-free, hard carbon layer to the thickness Tm of the metal-containing, hard carbon layer being 2-8.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.