US 12,345,336 B1
Piston ring with hard plating, and preparation method therefor
Kaishun Li, Yizheng (CN); Qianxi Liu, Yizheng (CN); Yueting Zhou, Yizheng (CN); and Guanfei Shi, Yizheng (CN)
Assigned to Asimco Shuanghuan Piston Ring (yizheng) Co., Ltd., Yizheng (CN)
Filed by Asimco Shuanghuan Piston Ring (yizheng) Co., Ltd., Yizheng (CN)
Filed on Apr. 3, 2024, as Appl. No. 18/625,273.
Claims priority of application No. 202410000422.2 (CN), filed on Jan. 2, 2024.
Int. Cl. F16J 9/26 (2006.01); C23C 14/00 (2006.01); C23C 14/06 (2006.01); C23C 14/16 (2006.01); C23C 14/34 (2006.01); C25D 3/06 (2006.01); C25D 3/10 (2006.01); C25D 5/18 (2006.01); C25D 7/04 (2006.01)
CPC F16J 9/26 (2013.01) [C23C 14/0084 (2013.01); C23C 14/0605 (2013.01); C23C 14/0641 (2013.01); C23C 14/165 (2013.01); C23C 14/345 (2013.01); C23C 14/3464 (2013.01); C25D 3/06 (2013.01); C25D 3/10 (2013.01); C25D 5/18 (2013.01); C25D 7/04 (2013.01)] 1 Claim
OG exemplary drawing
 
1. A piston ring with a hard plating, wherein an outer diameter (OD) surface and a side face of the piston ring respectively have the hard plating;
the hard plating of the OD surface of the piston ring consists of an interlayer, a gradient metal nitride layer, and a diamond-like carbon (DLC) repetitive unit layer sequentially from bottom to top on an OD surface of a piston ring matrix;
one DLC unit layer in the DLC repetitive unit layer consists of a DLC layer and a metal-doped DLC layer sequentially from bottom to top; a number of repetitions of the DLC unit layer is 4 to 6;
the interlayer is a chrome layer; the gradient metal nitride layer is a gradient titanium nitride layer; the metal-doped DLC layer is a titanium-doped DLC layer;
a thickness of the interlayer is 1 μm to 4 μm;
a thickness of the gradient metal nitride layer is 0.1 μm to 2 μm;
a thickness of the DLC layer in the one DLC unit layer is 4 μm to 8 μm;
a thickness of the metal-doped DLC layer in the one DLC unit layer is 100 nm to 500 nm;
a total thickness of the DLC repetitive unit layer is 25.5 μm to 37 μm;
the hard plating of the side face of the piston ring is a chrome plating on a side face of the piston ring matrix; and a thickness of the chrome plating is 1 μm to 20 μm.