Low friction coatings with improved abrasion and wear properties and methods of making

Patent metadata

Field	Value
Publication number	US-9617654-B2
Application number	US-201213724403-A
Country	US
Kind code	B2
Filing date	Dec 21, 2012
Priority date	Dec 21, 2012
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

Provided are low friction coatings with improved abrasion, wear resistance and methods of making such coatings. In one form, the coating includes: i) an under layer selected from the group consisting of CrN, TiN, TiAlN, TiAlVN, TiAlVCN, TiSiN, TiSiCN, TiAlSiN and combinations thereof, wherein the under layer ranges in thickness from 0.1 to 100 μm, ii) an adhesion promoting layer selected from the group consisting of Cr, Ti, Si, W, CrC, TiC, SiC, WC, and combinations thereof, wherein the adhesion promoting layer ranges in thickness from 0.1 to 50 μm and is contiguous with a surface of the under layer, and iii) a functional layer selected from the group consisting of a fullerene based composite, a diamond based material, diamond-like-carbon and combinations thereof, wherein the functional layer ranges from 0.1 to 50 μm and is contiguous with a surface of the adhesion promoting layer.

First claim

What is claimed is:

1. A multi-layer low friction coating comprising:
i) an under layer comprising CrN, wherein the under layer ranges in thickness from 5 to 15 μm,
ii) an optional adhesion promoting layer comprising CrC, wherein the adhesion promoting layer ranges in thickness from 5 to 15 μm and is contiguous with a surface of the under layer, and
iii) a functional layer comprising diamond-like-carbon (DLC), wherein the functional layer ranges from 5 to 15 μm and is contiguous with a surface of the optional adhesion promoting layer or a surface of the under layer, and wherein the diamond-like-carbon (DLC) is selected from the group consisting of ta-C, DLCH, and combinations thereof,
wherein the optional adhesion promoting layer is interposed between the under layer and the functional layer,
wherein the coefficient of friction of the functional layer of the low friction coating as measured by the block on ring friction test is less than or equal to 0.15, and
wherein the abrasion resistance of the low friction coating as measured by the modified ASTM G105 abrasion test yields a wear scar depth of less than or equal to 20 μm and a weight loss less than or equal to 0.02 grams.

2. The coating of claim 1 , wherein the under layer is contiguous with a surface of a substrate.

3. The coating of claim 2 , wherein the substrate is selected from the group consisting of steel, stainless steel, hardbanding, an iron alloy, an aluminum based alloy, a titanium based alloy, ceramics and a nickel based alloy.

4. The coating of claim 3 , wherein the hardbanding comprises a cermet based material, a metal matrix composite or a hard metallic alloy.

5. The coating of claim 1 , wherein the under layer hardness ranges from 800 to 3500 VHN.

6. The coating of claim 1 , wherein the adhesion promoting layer hardness ranges from 200 to 2500 VHN.

7. The coating of claim 1 , wherein the functional layer hardness ranges from 1000 to 7500 VHN.

8. The coating of claim 1 , wherein the adhesion promoting layer is present, the coating further including a gradient at the interface of the under layer and the adhesion promoting layer ranging from 0.01 to 10 μm.

9. The coating of claim 1 , wherein the adhesion promoting layer is present, the coating further including a gradient at the interface of the adhesion promoting layer and the functional layer ranging from 0.01 to 10 μm.

10. The coating of claim 1 , wherein the adhesion promoting layer is present, the coating further including a second adhesion promoting layer comprising CrC, wherein the second adhesion promoting layer ranges in thickness from 0.1 to 2 μm and is contiguous with a surface of the functional layer, and a second functional layer comprising diamond-like-carbon (DLC), wherein the second functional layer ranges from 0.1 to 2 μm and is contiguous with a surface of the second adhesion promoting layer.

11. The coating of claim 10 , wherein the diamond-like-carbon (DLC) is selected from the group consisting of ta-C, DLCH, and combinations thereof.

12. The coating of claim 1 , wherein the surface roughness of the functional layer ranges from 0.01 μm to 1.0 μm Ra.

13. The coating of claim 1 , wherein the abrasion resistance of the low friction coating as measured by the modified ASTM G105 abrasion test yields a wear scar depth and a weight loss at least 5 times lower than a single layer coating of the same functional layer.

14. The coating of claim 1 , wherein the coating is applied to a portion of the surface of a device selected from the group consisting of a drill bit for subterraneous rotary drilling, a drill stem assembly for subterraneous rotary drilling, a casing, a tubing, couplings, a work string, a coiled tubing, a pipe, a riser, a plunger, centralizers, a completion string, a production string, and a petrochemical and chemical production device.

15. A method of making a multi-layer low friction coating comprising:
i) providing a substrate for coating,
ii) depositing on a surface of the substrate an under layer comprising CrN, wherein the under layer ranges in thickness from 5 to 15 μm,
iii) depositing optionally on the surface of the under layer an adhesion promoting layer comprising CrC, wherein the adhesion promoting layer ranges in thickness from 5 to 15 μm and is contiguous with a surface of the under layer, and
iv) depositing on the surface of the optional adhesion promoting layer or on the surface of the under layer a functional layer comprising diamond-like-carbon (DLC), wherein the functional layer ranges from 5 to 15 μm and is contiguous with a surface of the optional adhesion promoting layer or a surface of the under layer, and wherein the diamond-like-carbon (DLC) is selected from the group consisting of ta-C, DLCH, and combinations thereof,
wherein the coefficient of friction of the functional layer of the low friction coating as measured by the block on ring friction test is less than or equal to 0.15, and
wherein the abrasion resistance of the low friction coating as measured by the modified ASTM G105 abrasion test yields a wear scar depth of less than or equal to 20 μm and a weight loss less than or equal to 0.02 grams.

16. The method of claim 15 , further including depositing from 1 to 100 series of incremental coating layers, wherein each series of incremental coating layers includes a combination of an incremental adhesion promoting layer, an incremental functional layer and an optional incremental under layer, wherein the each series of incremental coating layers is configured as follows:
(i) wherein the optional incremental under layer is selected from the group consisting of CrN, TiN, TiAlN, TiAlVN, TiAlVCN, TiSiN, TiSiCN, TiAlSiN and combinations thereof; ranges in thickness from 0.1 to 100 μm; and is contiguous with a surface of the functional layer and the incremental adhesion promoting layer; wherein the optional incremental under layer is interposed between the functional layer and the incremental adhesion promoting layer,
(ii) wherein the incremental adhesion promoting layer is selected from the group consisting of Cr, Ti, Si, W, CrC, TiC, SiC, WC, and combinations thereof; ranges in thickness from 0.1 to 50 μm; and is contiguous with a surface of the functional layer or optional incremental under layer, and the incremental functional layer;
wherein the incremental adhesion promoting layer is interposed between the functional layer and the incremental functional layer or between the optional incremental under layer and the incremental functional layer

(iii) wherein the incremental functional layer is selected from the group consisting of a fullerene based composite, a diamond based material, diamond-like-carbon (DLC), and combinations thereof; ranges from 0.1 to 50 μm in thickness; and is contiguous with a surface of the incremental adhesion promoting layer.

17. The method of claim 15 , wherein the substrate is selected from the group consisting of steel, stainless steel, hardbanding, an iron alloy, an aluminum based alloy, a titanium based alloy, ceramics and a nickel based alloy.

18. The method of claim 17 , wherein the hardbanding comprises a cermet based material, a metal matrix composite or a hard metallic alloy.

19. The method of claim 15 , wherein the under layer hardness ranges from 800 to 3500 VHN.

20. The method of claim 15 , wherein the adhesion promoting layer hardness ranges from 200 to 2500 VHN.

21. The method of claim 15 , wherein the functional layer hardness ranges from 1000 to 7500 VHN.

22. Th

Assignees

• Exxonmobil Res & Eng Co

Inventors

• Rajagopalan Srinivasan
• Haque Tabassumul
• Ertas Mehmet Deniz
• Ozekcin Adnan
• Jin Hyunwoo
• Zhao Bo

Classifications

• Y10T428/24975

  No layer or component greater than 5 mils thick · CPC title

• C23C28/046

  with at least one amorphous inorganic material layer, e.g. DLC, a-C:H, a-C:Me, the layer being doped or not · CPC title

• E21B17/00

  Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; {Cables;} Casings; Tubings · CPC title

• C23C28/322

  only coatings of metal elements only · CPC title

• C23C16/0272

  Deposition of sub-layers, e.g. to promote the adhesion of the main coating · CPC title