Ceramic material for high temperature service

Patent metadata

Field	Value
Publication number	US-11046614-B2
Application number	US-201715836369-A
Country	US
Kind code	B2
Filing date	Dec 8, 2017
Priority date	Oct 7, 2005
Publication date	Jun 29, 2021
Grant date	Jun 29, 2021

Abstract

A high purity yttria or ytterbia stabilized zirconia powder wherein a purity of the zirconia is at least 99.5 weight percent purity and with a maximum amount of specified oxide impurities.

First claim

What is claimed:

1. A high purity yttria or ytterbia stabilized zirconia powder having a purity of at least 99.5 weight percent purity and a maximum amount of oxide impurities is as follows:
less than 0.005 weight percent SiO 2 ;
less than 0.015 weight percent Al 2 O 3 ;
less than 0.002 weight percent TiO 2 ; and
less than 0.002 weight percent MgO.

2. The powder of claim 1 , wherein the maximum amount of oxide impurities is further as follows:
less than 0.04 weight percent Fe 2 O 3 ;
less than 0.02 weight percent CaO; and
less than 0.001 weight percent Cr 2 O 3 ; and
less than 0.002 weight percent Na 2 O.

3. The powder of claim 1 , wherein the powder is a thermal sprayable powder.

4. The powder of claim 1 , wherein the zirconia is partially stabilized by the yttria.

5. The powder of claim 1 , wherein said powder has a particle size of from about 5 to 150 microns.

6. A method of applying a thermal barrier coating on a substrate, the method comprising:
thermally spraying the powder of claim 1 onto the substrate so as to form the thermal barrier coating having from about 5 to 250 vertical macro cracks per 25.4 mm length measured along a coating surface and being oriented perpendicular to a surface of the substrate containing said coating.

7. A high purity yttria or ytterbia stabilized hafnia powder having a purity of at least 99.5 weight percent purity and a maximum amount of oxide impurities is as follows:
less than 0.002 weight percent Na 2 O;
less than 0.005 weight percent SiO 2 ;
less than 0.015 weight percent Al 2 O 3 ;
less than 0.002 weight percent TiO 2 ;
less than 0.04 weight percent Fe 2 O 3 ;
less than 0.02 weight percent CaO;
less than 0.002 weight percent MgO; and
less than 0.001 weight percent Cr 2 O 3 .

8. The powder of claim 7 , wherein the powder is a thermal sprayable powder.

9. The powder of claim 7 , wherein the hafnia is partially stabilized by the yttria.

10. The powder of claim 7 , wherein said powder has a particle size of from about 5 to 150 microns.

11. A method of applying a thermal barrier coating on a substrate, the method comprising:
thermally spraying the powder of claim 7 onto the substrate so as to form the thermal barrier coating having from about 5 to 250 vertical macro cracks per 25.4 mm length measured along a coating surface and being oriented perpendicular to a surface of the substrate containing said coating.

12. A high purity yttria stabilized zirconia powder comprising:
a purity of at least 99.5 weight percent purity, less than about 0.005 weight percent silicon dioxide (silica), less than about 0.015 weight percent aluminum oxide (alumina), less than about 0.02 weight percent calcium oxide, less than about 0.04 weight percent ferric oxide, less than about 0.002 weight percent magnesium oxide, and less than about 0.002 weight percent titanium dioxide.

13. The powder of claim 12 , wherein the powder is a thermal sprayable powder.

14. The powder of claim 12 , wherein the zirconia is partially stabilized by the yttria.

15. The powder of claim 12 , wherein said powder has a particle size of from about 5 to 150 microns.

16. A method of applying a thermal barrier coating on a substrate, the method comprising:
thermally spraying the powder of claim 12 onto the substrate so as to form the thermal barrier coating having from about 5 to 250 vertical macro cracks per 25.4 mm length measured along a coating surface and being oriented perpendicular to a surface of the substrate containing said coating.

17. A method of coating a substrate with a thermal barrier coating (TBC) on a substrate via thermal spray, the method comprising:
spraying a powder coating material comprising a yttria stabilized material comprising zirconia and hafnia and a purity of at least 99.5 weight percent and total impurities of said powder coating material comprises less than or equal to: about 0.005 weight percent silica, about 0.002 weight percent titania, and about 0.002 weight percent magnesia; and
forming a TBC coating by depositing the coating material in the form of a collection of frozen droplets or splats,
wherein the TBC coating comprises vertical cracks arranged at repeating intervals and extending in a thickness direction of said thermal barrier coating.

18. A high purity yttria stabilized zirconia and/or hafnia coating material with a purity of at least 99.5 weight percent purity and a maximum amount of oxide impurities is as follows:
less than 0.005 weight percent SiO 2 ;
less than 0.015 weight percent Al 2 O 3 ;
less than 0.002 weight percent TiO 2 ; and
less than 0.002 weight percent MgO.

19. The coating material of claim 18 , wherein the coating material is a powder.

20. The coating material of claim 19 , wherein the maximum amount of oxide impurities also includes:
less than 0.04 weight percent Fe 2 O 3 ; and
less than 0.02 weight percent CaO.

Assignees

• Oerlikon Metco Us Inc

Inventors

• Doesburg Jacobus
• Dorfman Mitchell
• Gold Matthew
• Xie Liangde

Classifications

• Y02E20/16

  Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT] · CPC title

• C04B35/486 Primary

  Fine ceramics · CPC title

• C23C30/00

  Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process (C23C26/00, C23C28/00 take precedence) · CPC title

• C23C14/083

  of refractory metals or yttrium · CPC title

• C04B2235/3225

  Yttrium oxide or oxide-forming salts thereof · CPC title