Synthetic diamond coatings with intermediate bonding layers and methods of applying such coatings

• US 6,165,616 A
• Filed: 05/16/1997
• Issued: 12/26/2000
• Est. Priority Date: 06/07/1995
• Status: Expired due to Fees

• Current Assignee: Syndia Corporation
• Original Assignee: James G. Conley, Jerome H. Lemelson
• Inventors: Lemelson, Jerome H., Conley, James G.
• Primary Examiner(s): TURNER, ARCHENE A
• Application Number:
  US08/857,423
• Time in Patent Office: 1,320 Days
• Field of Search: 428/408, 428/212, 428/457, 428/698, 428/336, 428/697, 428/699
• US Class Current: 428/408
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2002/30929 having at least two superposed coatings
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00047 Aluminium or Al-based alloys
• CPC Class Codes: A61F 2310/00179 Ceramics or ceramic-like structures
• CPC Class Codes: A61F 2310/0058 Coating made of diamond or of diamond-like carbon DLC
• CPC Class Codes: A61F 2310/0073 Coating or prosthesis-covering structure made of compounds based on metal carbides
• CPC Class Codes: A61F 2310/00856 Coating or prosthesis-covering structure made of compounds based on metal nitrides
• CPC Class Codes: C23C 14/0605 Carbon
• CPC Class Codes: C23C 14/0611 Diamond
• CPC Class Codes: C23C 16/0272 Deposition of sub-layers, e.g. to promote the adhesion of the main coating
• CPC Class Codes: C23C 16/0281 of metallic sub-layers C23C16/029 takes precedence
• CPC Class Codes: C23C 16/27 Diamond only
• CPC Class Codes: C23C 16/279 control of diamond crystallography
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/30 Self-sustaining carbon mass or layer with impregnant or other layer
• CPC Class Codes: Y10T 428/31678 Of metal

Abstract

A process is disclosed for making new and improved diamond, "diamond-like carbon" (a-C) and "diamond-like hydrocarbon" (a-C:H) coatings bonded to substrates by using intermediate bonding layers engineered to reduce the residual stress in the diamond coatings.

Claims

1. An article of manufacture comprising:

a. a substrate having at least one exterior surface;

b. at least one intermediate coating covering at least part of said exterior surface; and

c. an outer layer, selected from the group consisting of synthetic diamond and diamond-like carbon covering at least part of said intermediate coating,

wherein the Young'"'"'s modulus, thermal expansion coefficient and Poisson ratio of said intermediate coating are predetermined by means of geometric element analysis to be such that the residual Von Mises stress in said outer layer is minimized.

2. The article of manufacture claimed in claim 1 wherein said substrate is selected from the group consisting of cast aluminum, mild steel, Al--SiC(p) composite, Ti--6Al--4V alloy and a superalloy comprised primarily of nickel.

3. The article of manufacture claimed in claim 1 wherein said article of manufacture is a ceramic substrate selected from the group consisting of high strength carbides, nitrides, silicides, oxides and borides of aluminum, iron and nickel.

4. The article of manufacture of claim 1 wherein said intermediate coating has a thickness of between about 10 micro-meters and about 50 micro-meters.

5. The article of manufacture claimed in claim 1 wherein said intermediate coating is selected from the group consisting of carbides of aluminum, silicon, titanium, tungsten, boron, molybdenum, zirconium or tantalum.

6. The article of manufacture claimed in claim 1 wherein said intermediate coating is selected from the group consisting of nitrides of aluminum, silicon, titanium, tungsten, boron, molybdenum, zirconium or tantalum.

7. The article of manufacture claimed in claim 1 wherein said intermediate coating is a Si--Al--O--N ceramic.

8. The article of manufacture claimed in claim 1 wherein said outer layer is applied by chemical vapor deposition.

9. The article of manufacture of claim 1 wherein said substrate is cast aluminum and said intermediate coating has a thickness between about 10 to 50 micro-meters;

a Young'"'"'s modulus of between about 71 GPa to about 1000 GPa;

a Poisson ratio of between about 0.07 and 0.44 and a thermal expansion coefficient between about 1×

10^-6 /°

K and about 21×

10^-6 /°

K.

10. The article of manufacture of claim 1 wherein said substrate is mild steel and said intermediate coating has a thickness between about 10 to 50 micro-meters;

a Young'"'"'s modulus of between about 196 GPa to about 1000 GPa;

a Poisson ratio of between about 0.065 and 0.33 and a thermal expansion coefficient between about 1×

10^-6 /°

K and about 13×

10^-6 /°

K.

11. The article of manufacture of claim 1 wherein said substrate is Ti--6Al--4V and said intermediate coating has a thickness between about 10 to 50 micro-meters;

a Young'"'"'s modulus of between about 100 GPa to about 1000 GPa;

a Poisson ratio of between about 0.065 and 0.40 and a thermal expansion coefficient between about 1×

10^-6 /° and

about 7×

10^-6 /°

.

12. The article of manufacture of claim 1 wherein said substrate is nickel superalloy and said intermediate coating has a thickness between about 10 to 50 micro-meters;

a Young'"'"'s modulus of between about 200 GPa to about 1000 GPa;

a Poisson ratio of between about 0.065 and 0.35 and a thermal expansion coefficient between about 1×

10^-6 /° and

about 15×

10^-6 /°

.

13. The article of manufacture of claim 1 wherein said substrate is Al--SiC(p) and said intermediate coating has a thickness between about 10 to 50 micro-meters;

a Young'"'"'s modulus of between about 85 GPa to about 1000 GPa;

a Poisson ratio of between about 0.065 and 0.36 and a thermal expansion coefficient between about 1×

10^-6 /° and

about 20×

10^-6 /°

.

14. An article of manufacture comprising:

a. a substrate having at least one exterior surface;

b. at least one intermediate coating having a predetermined thickness and covering at least part of said exterior surface; and

c. an outer layer, selected from the group consisting of synthetic diamond and diamond-like carbon covering at least part of said intermediate coating,

wherein the thickness of said intermediate coating is predetermined by means of geometric element analysis to minimize the residual Von Mises stress in said outer layer.

15. The article of manufacture claimed in claim 14 wherein said substrate is selected from the group consisting of cast aluminum, mild steel, Al--SiC(p) composite, Ti--6Al--4V alloy and a superalloy comprised primarily of nickel.

16. The article of manufacture claimed in claim 14 wherein said article of manufacture is a ceramic substrate selected from the group consisting of high strength carbides, nitrides, silicides, oxides and borides of aluminum, iron and nickel.

17. The article of manufacture of claim 14 wherein said intermediate coating has a thickness of between about 10 micro-meters and about 50 micro-meters.

18. The article of manufacture claimed in claim 14 wherein said intermediate coating is selected from the group consisting of carbides of aluminum, silicon, titanium, tungsten, boron, molybdenum, zirconium or tantalum.

19. The article of manufacture claimed in claim 14 wherein said intermediate coating is selected from the group consisting of nitrides of aluminum, silicon, titanium, tungsten, boron, molybdenum, zirconium or tantalum.

20. The article of manufacture claimed in claim 14 wherein said intermediate coating is a Si--Al--O--N ceramic.

21. The article of manufacture claimed in claim 14 wherein said outer layer is applied by chemical vapor deposition.