Piston ring for engine

Patent metadata

Field	Value
Publication number	US-9482343-B2
Application number	US-201213611177-A
Country	US
Kind code	B2
Filing date	Sep 12, 2012
Priority date	Mar 16, 2012
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

Disclosed is a piston ring for engine that includes chromium (Cr) coating layer coated on the surface of a base material of the piston ring of an engine; a chromium nitride (CrN) coating layer; and a silicon-incorporated diamond-like carbon (Si-DLC) coating layer, which is formed on the CrN coating layer, and contains Si component of about 3˜10 at %, and a method for manufacturing thereof.

First claim

What is claimed is:

1. A piston ring for an engine comprising:
a chromium (Cr) coating layer coated on the surface of a base material;
a chromium nitride (CrN) coating layer coated on the Cr coating layer; and
a silicon-incorporated diamond-like carbon (Si-DLC) coating layer, which is formed on the CrN coating layer, and alternately laminated with low content layers containing a first Si component of 3 at % or less (not including 0 (zero)) and high content layers containing a second Si component of more than 3 at % and 10 at % or less, wherein a rigidity of the low content layers is higher than that of the high content layers,
wherein the low content layers and the high content layers are essentially the same except for the Si content.

2. The piston ring for an engine of claim 1 , wherein a thickness of each of low content layers and a thickness of each of the high content layers is 50 nm or less (not including 0 (zero)), respectively.

3. The piston ring for an engine of claim 1 , wherein an outer-most layer of the high content layers is the outer-most layer of the Si-DLC coating layer.

4. The piston ring for an engine of claim 1 , wherein the Si-DLC coating layer is formed by a chemical reaction of hydrocarbon gas (C x H y ) and TMS (Tetra-methylsilane, Si(CH 3 ) 4 ) gas, or hydrocarbon gas and HMDSO (Hexamethyldisiloxane, O(Si(CH 3 ) 3 ) 2 ) gas.

5. A method of forming a piston ring for an engine, the method comprising:
coating a chromium (Cr) coating layer on the surface of a base material;
coating a chromium nitride (CrN) coating layer on the Cr coating layer; and
forming a silicon-incorporated diamond-like carbon (Si-DLC) coating layer on the CrN coating layer by alternately laminating the CrN coating layer with low content layers containing a first Si component of 3 at % or less (not including 0 (zero)) and high content layers containing a second Si component of more than 3 at % and 10 at % or less, wherein a rigidity of the low content layers is higher than that of the high content layers,
wherein the low content layers and the high content layers are essentially the same except for the Si content.

6. The method of claim 5 , wherein a thickness of each of the low content layers and a thickness of each of the high content layers is 50 nm or less (not including 0 (zero)), respectively.

7. The method claim 5 , wherein an outer-most layer of the high content layers is the outer-most layer of the Si-DLC coating layer.

8. The method of claim 5 , further comprising: forming the Si-DLC coating layer by a chemical reaction of hydrocarbon gas (C x H y ) and TMS (Tetra-methylsilane, Si(CH 3 ) 4 ) gas, or hydrocarbon gas and HMDSO (Hexamethyldisiloxane, O(Si(CH 3 ) 3 ) 2 ) gas.

Assignees

• Shim So Jung
• An Jeong Uk
• Hyundai Motor Co Ltd

Inventors

• Shim So Jung
• An Jeong Uk

Classifications

• F16J9/26 Primary

  characterised by the use of particular materials · CPC title

• F02F5/00 Primary

  Piston rings, e.g. associated with piston crown · CPC title