Carbon-carbon composite including hydrophobic coating

Patent metadata

Field	Value
Publication number	US-10119585-B2
Application number	US-201614990564-A
Country	US
Kind code	B2
Filing date	Jan 7, 2016
Priority date	Jan 7, 2016
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

In some examples, an article may include a carbon-carbon composite, an antioxidant in pores in a surface of the carbon-carbon composite, and a hydrophobic coating on the surface. The hydrophobic coating includes an oxide of a metal. The metal has a Pauling electronegativity of less than about 1.7. In some examples, the article may be a carbon-carbon composite brake disk that includes a carbon-carbon composite substrate defining a friction surface and a non-friction surface. The antioxidant may be a phosphate-based antioxidant, and the antioxidant may be in pores in the non-friction surface. In some examples, the hydrophobic coating is on the non-friction surface over the phosphate-based antioxidant. In some examples, the hydrophobic coating may include a majority of at least one of yttrium oxide, scandium oxide, or zirconium oxide.

First claim

What is claimed is:

1. An article comprising:
a carbon-carbon composite brake disk defining a friction surface and a non-friction surface, wherein the non-friction surface comprises a sub-surface region;
a phosphate-based antioxidant in pores in the sub-surface region of the non-friction surface of the carbon-carbon composite brake disk; and
a hydrophobic coating on the non-friction surface of the carbon-carbon composite brake disk, the hydrophobic coating comprising a majority by weight of an oxide of a first metal, wherein the first metal has a Pauling electronegativity of less than about 1.7, and wherein the hydrophobic coating excludes oxides of second metals, the second metals having a Pauling electronegativity of greater than 1.7.

2. The article of claim 1 , wherein the hydrophobic coating consists essentially of the oxide of the first metal having the Pauling electronegativity of less than about 1.7.

3. The article of claim 1 , wherein the oxide of the first metal has a standard free energy of formation that is less than the standard free energy of formation of carbon monoxide at all temperatures below 1000° C.

4. The article of claim 1 , wherein the first metal comprises at least one of Y, Sc, or Zr.

5. The article of claim 1 , wherein the first metal is Y.

6. The article of claim 1 , wherein the first metal and the oxide of the first metal do not promote oxidation of the carbon.

7. A method of forming the article of claim 1 , the method comprising:
infiltrating the phosphate-based antioxidant into pores in the sub-surface region of the non-friction surface of the carbon-carbon composite brake disk, wherein the carbon-carbon composite brake disk defines the non-friction surface and the friction surface; and
forming the hydrophobic coating on the non-friction surface of the carbon-carbon composite brake disk over the sub-surface region, wherein the hydrophobic coating comprises a majority by weight of the oxide of the first metal, wherein the first metal has a Pauling electronegativity of less than about 1.7, and wherein the hydrophobic coating excludes oxides of second metals, the second metals having a Pauling electronegativity of greater than 1.7.

8. The method of claim 7 , wherein forming the hydrophobic coating comprises applying a solution or slurry comprising a solvent and the oxide of the first metal or the solvent and a precursor of the oxide of the first metal to the non-friction surface of the carbon-carbon composite brake disk to form a coated carbon-carbon composite brake disk.

9. The method of claim 8 , further comprising:
heating the coated carbon-carbon composite brake disk to evaporate substantially all of the solvent and form a dried carbon-carbon composite brake disk.

10. The method of claim 9 , wherein the solution or slurry comprising the oxide of the first metal or the precursor of the oxide of the first metal and the solvent comprises a solution comprising a salt precursor of the oxide of the first metal and the solvent, the method further comprising:
heating the dried carbon-carbon composite at a temperature that facilitates decomposition of the salt precursor of the oxide of the first metal to the oxide of the first metal.

11. The method of claim 7 , wherein forming the hydrophobic coating comprises applying the hydrophobic coating using sol-gel processing or from a colloidal suspension.

12. A carbon-carbon composite brake disk comprising:
a carbon-carbon composite substrate defining a friction surface and a non-friction surface;
a phosphate-based antioxidant in pores in a sub-surface region below the non-friction surface; and
a hydrophobic coating on the non-friction surface over the phosphate-based antioxidant, wherein the hydrophobic coating comprises a majority by weight of at least one of yttrium oxide, scandium oxide, or zirconium oxide, and wherein the hydrophobic coating excludes metal oxides of metals that have a Pauling electronegativity of greater than 1.7.

13. The carbon-carbon composite brake disk of claim 12 , wherein the hydrophobic coating consists essentially of the at least one of yttrium oxide, scandium oxide, or zirconium oxide.

14. The carbon-carbon composite brake disk of claim 12 , wherein the hydrophobic coating is substantially free of materials that catalyze carbon oxidation.

Assignees

• Honeywell Int Inc

Inventors

• Rateick Jr Richard George
• Yates Stephen Frederic

Classifications

• C04B41/89

  for obtaining at least two superposed coatings having different compositions · CPC title

• C04B2111/00362

  Friction materials, e.g. used as brake linings, anti-skid materials · CPC title

• F16D2250/0046

  Coating · CPC title

• F16D2200/0082

  Production methods therefor · CPC title

• C23C16/045

  Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates · CPC title