	US 12,012,657 B2
	Part coated with a hydrogenated amorphous carbon coating on an undercoat comprising chromium, carbon and silicon
Laurent Bombillon, Andrézieux Bouthéon (FR); and Fabrice Prost, Saint-Etienne (FR)
Assigned to HYDROMECANIQUE ET FROTTEMENT, Andrézieux Bouthéon (FR)
Appl. No. 17/252,615
Filed by HYDROMECANIQUE ET FROTTEMENT, Andrézieux Bouthéon (FR)
PCT Filed Jun. 17, 2019, PCT No. PCT/FR2019/051462 § 371(c)(1), (2) Date Dec. 15, 2020, PCT Pub. No. WO2019/243720, PCT Pub. Date Dec. 26, 2019.
Claims priority of application No. 1855319 (FR), filed on Jun. 18, 2018.
Prior Publication US 2021/0254220 A1, Aug. 19, 2021
Int. Cl. B32B 9/00 (2006.01); C23C 16/02 (2006.01); C23C 16/26 (2006.01); C23C 16/32 (2006.01); C23C 28/00 (2006.01); C23C 28/04 (2006.01); F16J 9/26 (2006.01)

CPC C23C 28/046 (2013.01) [C23C 16/0272 (2013.01); C23C 16/26 (2013.01); C23C 16/32 (2013.01); C23C 28/048 (2013.01); C23C 28/34 (2013.01); F16J 9/26 (2013.01)]

20 Claims

1. Part comprising a metal substrate, a hydrogenated amorphous carbon coating, of a-C:H type, coating the substrate, and a sub-layer based on chromium (Cr), carbon (C) and silicon (Si) disposed between the metal substrate and the amorphous carbon coating and on which the amorphous carbon coating is applied, wherein the sub-layer comprises the following atomic ratios at its interface with the amorphous carbon coating:

a ratio between the silicon content and the chromium content (Si/Cr) comprised between 0.35 and 0.60, and

a ratio between the carbon content and the silicon content (C/Si) comprised between 2.5 and 3.5.