Ceramic matrix composites and methods of making the same

Patent metadata

Field	Value
Publication number	US-2016159698-A1
Application number	US-201514958156-A
Country	US
Kind code	A1
Filing date	Dec 3, 2015
Priority date	Dec 4, 2014
Publication date	Jun 9, 2016
Grant date	—

Abstract

An improved method of preparing ceramic matrix composites includes blending one or more ceramic powders with one or more paraffinic binders to form a slurry; introducing a ceramic fiber preform into a die or mold; heating the slurry to a temperature above the melting point of the one or more paraffinic binders to form a heated slurry; introducing the heated slurry into the die or mold, the heated slurry infiltrating the ceramic fiber preform to form a slurry infiltrated preform; cooling the die or mold below the solidification temperature of the paraffinic binder, thereby forming a solid component from the slurry infiltrated preform; removing the solid component from the die or mold; heating the solid component to a temperature whereby the paraffinic binder is removed; and densifying the solid component after removing the paraffinic binder, thereby forming the ceramic matrix composite.

First claim

1 . A method for preparing a ceramic matrix composite, the method comprising:
blending one or more ceramic powders with one or more paraffinic binders to form a slurry; introducing a ceramic fiber preform into a die or mold; heating the slurry to a temperature above the melting point of the one or more paraffinic binders to form a heated slurry; introducing the heated slurry into the die or mold, the heated slurry infiltrating the ceramic fiber preform to form a slurry infiltrated preform; cooling the die or mold below the solidification temperature of the paraffinic binder, thereby forming a solid component from the slurry infiltrated preform; removing the solid component from the die or mold; heating the solid component to a temperature whereby the paraffinic binder is removed; and densifying the solid component after removing the paraffinic binder, thereby forming the ceramic matrix composite.

2 . The method of claim 1 , wherein the densifying is by melt infiltration.

3 . The method of claim 1 , wherein the densifying is by polymer impregnation and pyrolysis.

4 . The method of claim 1 , wherein the slurry comprises from about 20% to about 70% by volume of the one or more ceramic powders.

5 . The method of claim 1 , wherein the slurry comprises from about 30% to about 80% by volume of the one or more paraffinic binders.

6 . The method of claim 4 , wherein the slurry comprises from about 30% to about 80% by volume of the one or more paraffinic binders.

7 . The method of claim 1 , wherein the one or more ceramic powders are selected from the group consisting of silicon carbide (SiC), silicon/silicon carbide, and combinations thereof.

8 . The method of claim 1 , wherein the one or more paraffinic binders are selected from the group consisting of paraffin wax, heavy mineral oil, and combinations thereof.

9 . The method of claim 5 , wherein the one or more paraffinic binders are mixed with one or more additional components selected from the group consisting of a surfactant and a high molecular weight polymer to form a paraffinic binder mixture.

10 . The method of claim 9 , wherein the paraffinic binder mixture includes a surfactant comprising one or more saturated or unsaturated C12-C16 fatty acids.

11 . The method of claim 10 , wherein the surfactant has a concentration in the paraffinic binder mixture of from about 1% to about 12% by weight.

12 . The method of claim 9 , wherein the paraffinic binder mixture comprises a high molecular weight polymer selected from the group consisting of polyethylene, microcrystalline wax and phenolic resin.

13 . The method of claim 12 , wherein the high molecular weight polymer has a concentration in the paraffinic binder mixture of from about 5% to about 75% by weight.

14 . The method of claim 1 , wherein the ceramic fiber preform is in the form of a fabric with a functional low modulus interphase coating.

15 . The method for the preparation of a ceramic matrix composite component of claim 1 , wherein the ceramic fiber preform is subjected to chemical vapor infiltration (CVI) prior to introduction to the die or mold.

16 . The method of claim 1 , wherein the mold or die is configured for extra fill volume in excess of the volume of the ceramic fiber preform.

17 . The method of claim 1 , wherein the heating to remove the paraffinic binder is to a temperature of at least about 600° C.

18 . A ceramic matrix composite prepared by the method of claim 1 .

Assignees

• Rolls Royce Corp

Inventors

• Landwehr Sean Erin

Classifications

• C04B35/65

  Reaction sintering of free metal- or free silicon-containing compositions {(C04B35/573, C04B35/591 take precedence)} · CPC title

• C04B35/62675

  characterised by the treatment temperature · CPC title

• C04B41/457 Primary

  Non-superficial impregnation or infiltration of the substrate · CPC title

• C04B35/78

  containing non-metallic materials · CPC title

• C04B35/63448

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title