Method for providing crystalline silicon-containing ceramic material

Patent metadata

Field	Value
Publication number	US-2016236986-A1
Application number	US-201415027705-A
Country	US
Kind code	A1
Filing date	Sep 24, 2014
Priority date	Oct 8, 2013
Publication date	Aug 18, 2016
Grant date	—

Abstract

Disclosed is a method for providing a crystalline ceramic material. In an example, the method includes providing a silicon-containing preceramic polymer material that can be thermally converted to one or more crystalline polymorphs. The silicon-containing preceramic polymer material includes dispersed therein an effective amount of dopant particles. The silicon-containing preceramic polymer material is then thermally converted to the silicon-containing ceramic material. The effective amount of dopant particles enhance the formation of at least one of the one or more crystalline polymorphs, relative to the silicon-containing preceramic polymer without the dopant particles, with respect to at least one of formation of a selected polymorph of the one or more crystalline polymorphs formed, an amount formed of a selected polymorph of the one or more crystalline polymorphs formed, and a temperature of formation of the one or more crystalline polymorphs.

First claim

What is claimed is:

1 . A method for providing a crystalline ceramic material, the method comprising:
providing a silicon-containing preceramic polymer material that can be thermally converted to one or more crystalline polymorphs, the silicon-containing preceramic polymer material including dispersed therein an effective amount of dopant particles; and thermally converting the silicon-containing preceramic polymer material to the silicon-containing ceramic material, the effective amount of dopant particles enhancing the formation of at least one of the one or more crystalline polymorphs, relative to the silicon-containing preceramic polymer without the dopant particles, with respect to at least one of:
formation of a selected polymorph of the one or more crystalline polymorphs formed,
an amount formed of a selected polymorph of the one or more crystalline polymorphs formed, and
a temperature of formation of the one or more crystalline polymorphs.

2 . The method as recited in claim 1 , wherein the dopant particles are carbon-containing particles.

3 . The method as recited in claim 2 , wherein the carbon-containing particles are alpha silicon carbide.

4 . The method as recited in claim 2 , wherein the carbon-containing particles are selected from the group consisting of boron carbide, nano-diamond, graphite, graphene, activated carbon, carbon nanotubes, and combinations thereof.

5 . The method as recited in claim 1 , wherein the dopant particles are nitride particles.

6 . The method as recited in claim 5 , wherein the nitride particles selected from the group consisting of aluminum nitride, gallium nitride, boron nitride, silicon nitride, and combinations thereof.

7 . The method as recited in claim 1 , wherein the silicon-containing ceramic material is silicon carbide.

8 . The method as recited in claim 1 , wherein the silicon-containing ceramic material is a silicon-carbon ceramic compound including an element selected from the group consisting of nitrogen, boron, oxygen and combinations thereof.

9 . The method as recited in claim 1 , wherein the silicon-containing preceramic polymer material includes, by weight, up to 40% of the dopant particles.

10 . The method as recited in claim 1 , wherein the silicon-containing preceramic polymer material includes, by weight, up to 20% of the dopant particles.

11 . The method as recited in claim 1 , wherein the silicon-containing preceramic polymer material includes, by weight, up to 10% of the dopant particles.

12 . The method as recited in claim 11 , wherein the silicon-containing preceramic polymer material includes, by weight, up to 5% of the dopant particles.

13 . The method as recited in claim 1 , wherein the silicon-containing ceramic material is silicon carbide, the silicon-containing preceramic polymer material includes, by weight, up to 10% of the dopant particles, the dopant particles are silicon carbide, and the silicon-containing preceramic polymer material is disposed within pores of a silicon carbide fiber structure.

14 . A method for enhancing crystallinity and limiting thermal damage in formation of a reinforced silicon-containing ceramic material, the method comprising:
providing a porous structure and a silicon-containing preceramic polymer material, the silicon-containing preceramic polymer material being thermally convertible into a silicon-containing ceramic material, wherein
a percent crystallinity of the silicon-containing ceramic material is a function F 1 of a temperature and time at which the silicon-containing preceramic polymer material is thermally converted, and
a degree of thermal damage to the porous structure is a function F 2 of the temperature and the time at which the silicon-containing preceramic polymer material is thermally converted,
providing the silicon-containing preceramic polymer material with dopant particles dispersed therein to shift upwards the function F 1 of the percent crystallinity; infiltrating pores of the porous structure with the silicon-containing preceramic polymer material having the dopant particles dispersed therein; and thermally converting the silicon-containing preceramic polymer material, at the temperature and given time, to a crystalline silicon-containing ceramic material.

15 . The method as recited in claim 14 , wherein the dopant particles are carbon-containing particles.

16 . The method as recited in claim 14 , wherein the dopant particles are nitride particles.

17 . The method as recited in claim 14 , wherein the silicon-containing preceramic polymer material includes, by weight, up to 10% of the dopant particles.

18 . A method for providing a crystalline ceramic material, the method comprising:
providing a silicon-containing preceramic polymer material that is thermally convertible to one or more of multiple crystalline polymorphs including a first crystalline polymorph and a second crystalline polymorph, the silicon-containing preceramic polymer material including dispersed therein crystal-specific dopant particles predominantly having the first crystalline polymorph; and thermally converting the silicon-containing preceramic polymer material to a silicon-carbon ceramic material, the crystal-specific dopant particles enhancing, relative to the silicon-containing preceramic polymer without the crystal-specific dopant particles, the formation of the silicon-carbon ceramic matrix in the first crystalline polymorph.

19 . The method as recited in claim 18 , wherein the silicon-carbon ceramic material is silicon carbide, the first crystalline polymorph is an alpha polymorph of silicon carbide, the second crystalline polymorph is a beta polymorph of silicon carbide, and the crystal-specific dopant particles are silicon carbide particles predominantly having the alpha polymorph.

Assignees

• United Technologies Corp

Inventors

• Limarga Andi
• Sheedy Paul
• Schmidt Wayde R
• Berczik Douglas M
• Kashyap Tania Bhatia
• Hermann Mark A

Classifications

• C04B2235/383

  Alpha silicon carbide · CPC title

• C04B2235/3873

  Silicon nitrides, e.g. silicon carbonitride, silicon oxynitride · CPC title

• C04B2235/386

  Boron nitrides · CPC title

• C04B2235/3865

  Aluminium nitrides · CPC title

• C04B35/571 Primary

  obtained from {Si-containing} polymer precursors {or organosilicon monomers} · CPC title