Claims
- 1. An alloy comprising a Pt-group metal, Ni and Al in relative concentration to provide a γ-Ni+γ′-Ni3Al phase constitution.
- 2. The alloy of claim 1, wherein the Pt-group metal is selected from the group consisting of Pt, Pd, Ir, Rh and Ru, and combinations thereof.
- 3. The alloy of claim 1, wherein the Pt-group metal is Pt.
- 4. The alloy of claim 1, further comprising a reactive element selected from the group consisting of Hf, Y, La, Ce and Zr, and combinations thereof.
- 5. The alloy of claim 4, wherein the reactive element is Hf.
- 6. The alloy of claim 1, further comprising a sufficient amount of a reactive element selected from the group consisting of Hf, Y, La, Ce and Zr, and combinations thereof to provide a γ′ phase constitution.
- 7. The alloy of claim 6, wherein the reactive element is Hf.
- 8. The alloy of claim 1, further comprising a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 9. The alloy of claim 4, further comprising a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 10. The alloy of claim 7, further comprising a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 11. An alloy comprising a Pt-group metal, Ni and Al, wherein the concentration of Al is limited with respect to the concentration of Ni and the concentration of the Pt-group metal such that the alloy includes substantially no β-NiAl phase.
- 12. The alloy of claim 11, wherein the Pt-group metal is selected from the group consisting of Pt, Pd, Ir, Rh and Ru, and combinations thereof.
- 13. The alloy of claim 11, wherein the Pt-group metal is Pt.
- 14. The alloy of claim 11, further comprising a reactive element selected from the group consisting of Hf, Y, La, Ce and Zr, and combinations thereof.
- 15. The alloy of claim 14, wherein the reactive element is Hf.
- 16. The alloy of claim 11, further comprising a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 17. The alloy of claim 14, further comprising a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 18. The alloy of claim 15, further comprising a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 19. A ternary Ni—Al-Pt alloy comprising less than about 23 at % Al, about 10 at % to about 30 at % of a Pt-group metal, and the remainder Ni.
- 20. The alloy of claim 19, wherein the Pt-group metal is Pt.
- 21. The alloy of claim 19, further comprising up to about 2 at % of a reactive element selected from the group consisting of Hf, Y, La, Ce and Zr, and combinations thereof.
- 22. The alloy of claim 21, wherein the reactive element is Hf.
- 23. The alloy of claim 21, wherein the reactive element is present in the alloy at a concentration of about 0.3 at % to about 2 at %.
- 24. The alloy of claim 19 comprising about 10 at % to about 22 at % Al and about 15 at % to about 30 at % of the Pt-group metal.
- 25. An alloy comprising Ni, Al and Pt as defined in the region A in FIG. 3.
- 26. An alloy comprising less than about 23 at % Al, about 10 at % to about 30 at % Pt, about 0.3 at % to about 2 at % Hf and the remainder Ni.
- 27. The alloy of claim 26, wherein Al is present at about 10 at % to about 22 at %, Pt is present at about 15 at % to about 30 at %, and Hf is present at about 0.5 at % to about 2 at %.
- 28. A coating composition comprising a Pt-group metal, Ni and Al, wherein the composition has a γ-Ni+γ′-Ni3Al phase constitution.
- 29. The coating composition of claim 28, further comprising a Pt-group metal selected from the group consisting of Pt, Pd, Ir, Rh and Ru, and combinations thereof.
- 30. The coating composition of claim 29, wherein the Pt-group metal is Pt.
- 31. The coating composition of claim 28, further comprising a reactive element selected from the group consisting of Hf, Y, La, Ce and Zr, and combinations thereof.
- 32. The coating composition of claim 31, wherein the reactive element is Hf.
- 33. The coating composition of claim 28, further comprising a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 34. The coating composition of claim 31, wherein the reactive element is present in the composition in a sufficient amount such that the composition has a γ′ phase constitution.
- 35. A metal coated with the composition of claim 28.
- 36. A metal coated with the composition of claim 31.
- 37. A metal coated with the composition of claim 32.
- 38. A thermal barrier coated article comprising:
(a) a superalloy substrate; (b) a bond coat on the substrate, wherein the bond coat comprises a Pt-group metal, Ni and Al, and wherein the bond coat has a γ-Ni+γ′-Ni3Al phase constitution.
- 39. The article of claim 38, wherein the Pt-group metal is selected from the group consisting of Pt, Pd, Ir, Rh and Ru, and combinations thereof.
- 40. The article of claim 39, wherein the Pt-group metal is Pt.
- 41. The article of claim 38, further comprising an adherent layer of oxide on the bond coat.
- 42. The article of claim 41, further comprising a ceramic coating on the adherent layer of oxide.
- 43. The article of claim 40, wherein the bond coat further comprises a reactive element selected from the group consisting of Hf, Y, La, Ce and Zr, and combinations thereof.
- 44. The article of claim 43, wherein the reactive element is Hf.
- 45. The article of claim 40, wherein the bond coat further comprises a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 46. A method for making a heat resistant substrate comprising applying on the substrate a coating comprising Ni and Al in a γ-Ni+γ′-Ni3Al phase structure.
- 47. The method of claim 46, wherein the coating further comprise a Pt-group metal selected from the group consisting of Pt, Pd, Ir, Rh and Ru, and combinations thereof.
- 48. The method of claim 47, wherein the Pt-group metal is Pt.
- 49. The method of claim 48, wherein the coating further comprises a reactive element selected from the group consisting of Hf, Y, La, Ce and Zr, and combinations thereof.
- 50. The method of claim 48, wherein the reactive element is Hf.
- 51. The method of claim 48, wherein the bond coat further comprises a metal selected from the group consisting of Cr, Co, Mo, Ta, and Re, and combinations thereof.
- 52. The method of claim 46, wherein the substrate is selected from Ni and Co superalloy articles.
- 53. A thermal barrier coated article comprising:
(a) a superalloy substrate; (b) a bond coat on the substrate, wherein the bond coat comprises a ternary alloy of Pt-Ni—Al, and wherein the alloy has a γ-Ni+γ′-Ni3Al phase constitution; (c) an adherent layer of oxide on the bond coat; and (d) a ceramic coating on the adherent layer of oxide.
- 54. The article of claim 53, wherein the bond coat further comprises Hf.
- 55. A method for reducing oxidation in γ-Ni+γ′-Ni3Al alloys, comprising adding at least one of a Pt-group metal and a reactive metal to the alloys.
- 56. The method of claim 55, wherein the Pt-group metal is Pt and the reactive metal is Hf.
- 57. A homogeneous coating comprising an alloy with a γ+γ′ phase constitution.
- 58. The coating of claim 57, wherein the alloy further comprises a Pt-group metal.
- 59. The coating of claim 58, wherein the Pt-group metal is Pt.
- 60. The coating of claim 58, wherein the alloy further comprises a reactive metal selected from the group consisting of Hf, Y, La, Ce and Zr, and combinations thereof.
- 61. The coating of claim 60, wherein the reactive metal is Hf.
- 62. The coating of claim 57, wherein the coating has a thickness of about 5 μm to about 100 μm.
- 63. The coating of claim 57, wherein the coating has a thickness of about 10 μm to about 50 μm.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0001] The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided by the terms of Contract Nos. N00014-00-1-0484 and N00014-02-1-0733, each awarded by the Office of Naval Research.