Claims
- 1. A method for forming a fiber reinforced composite, the fibers being at least one of elemental carbon, or silicon carbide, in a matrix of silicon carbide containing at least a silicon carbide phase and elemental silicon phase formed by molten silicon infiltration comprising: depositing a continuous metal nitride coating on the fibers wherein the metal is selected from the group consisting of silicon, aluminum, titanium, zirconium, hafnium, niobium, or tantalum, the metal nitride coating preventing reaction between the reinforcement fiber and molten silicon;
- admixing a carbonaceous material with the coated fibers so that at least 5 volume percent of the mixture is the coated fibers;
- forming the mixture into a preform having an open porosity ranging from about 25 volume percent to about 90 volume percent of the preform;
- heating the preform in an inert atmosphere or partial vacuum; and
- infiltrating the heated preform with molten silicon to form the silicon carbide matrix composite.
- 2. The method of claim 1 wherein the coating is about 0.1 to 5 microns.
- 3. The method of claim 2 wherein the step of depositing further comprises depositing on the metal nitride coating a second coating selected from the group consisting of: carbon, chromium, molybdenum, tantalum, titanium, tungsten; a metal carbide wherein the metal is silicon, tantalum, titanium, or tungsten; a metal silicide wherein the metal is chromium, molybdenum, tantalum, titanium, tungsten, or zirconium; a metal nitride wherein the metal is silicon, aluminum, titanium, zirconium, hafnium, niobium, tantalum, or boron; and a metal diboride wherein the metal is titanium, zirconium, hafnium, or aluminum.
- 4. The method of claim 3 wherein the step of depositing further comprises depositing carbon on the coated fibers.
- 5. The method of claim 1 wherein the metal nitride is from the group consisting of silicon, aluminum, and mixtures thereof.
- 6. The method of claim 5 wherein the step of depositing further comprises depositing on the metal nitride coating a second coating selected from the group consisting of boron nitride, titanium diboride, zirconium diboride, and hafnium diboride.
- 7. The method of claim 6 wherein the step of depositing further comprises depositing carbon on the coated fibers.
Parent Case Info
This application is a Continuation of application Ser. No. 08/057,919 filed May 7, 1993, now abnd which is a Continuation of Ser. No. 07/716,444, filed Jun. 17, 1991 now abnd. This application is related to applications Ser. No. 07/056,516 now U.S. Pat. No. 5,403,019, filed Jun. 1, 1987, Ser. No. 07/001,806 now U.S. Pat. No. 5,255,163, filed Sep. 24, 1987, Ser. No. 07/714,417, filed Jun. 12, 1991, now abandoned, Ser. No. 07/716,442, filed Jun. 17, 1991, now abandoned, and Ser. No. 07/716,443, filed Jun. 17, 1991 now abandoned.
US Referenced Citations (12)
Non-Patent Literature Citations (2)
Entry |
"Ceramic Coatings for Carbon-Carbon Composites", JR Strife & JE Sheehan, Ceramic Bulletin, vol. 67 ,No. 2, 1988, pp. 369-374. |
Handbook of Chemistry and Physics, CRC Press, 63rd Edition, 1982-83--Inside Cover. |
Continuations (2)
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Number |
Date |
Country |
Parent |
057919 |
May 1993 |
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Parent |
716444 |
Jun 1991 |
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