Rapid ceramic matrix composite fabrication of aircraft brakes via field assisted sintering
A method of making a ceramic matrix composite (CMC) brake component may include the steps of applying a pressure to a mixture comprising ceramic powder and chopped fibers, pulsing an electrical discharge across the mixture to generate a pulsed plasma between particles of the ceramic powder, increasing a temperature applied to the mixture using direct heating to generate the CMC brake component, and reducing the temperature and the pressure applied to the CMC brake component. The ceramic powder may have a micrometer powder size or a nanometer powder size, and the chopped fibers may have an interphase coating.
1. A method of making a ceramic matrix composite (CMC) brake component, the method comprising:
increasing a pressure from a first pressure to a second pressure in a mold containing a mixture comprising a ceramic powder and fibers;
pulsing an electrical discharge across the mixture to generate a pulsed plasma between particles of the ceramic powder;
generating the CMC brake component in response to increasing a temperature from a first temperature to a second temperature in the mold using direct heating; and
reduce the temperature and the pressure applied to the CMC brake component.
2. The method of claim 1 , wherein the ceramic powder comprises an average particle size ranging from micrometers to nanometers.
3. The method of claim 1 , wherein the ceramic powder comprises at least one of SiC, B 4 C, or Si 3 N 4 .
4. The method of claim 1 , wherein the fibers comprises at least one of chopped carbon fibers or chopped SiC fibers.
5. The method of claim 1 , wherein the mold comprises at least one of graphite, a refractory metal, or a ceramic.
6. The method of claim 1 , further comprising machining the CMC brake component.
7. The method of claim 1 , wherein the direct heating comprises resistance heating.
8. The method of claim 1 , wherein the direct heating comprises inductive heating.
9. The method of claim 1 , wherein the CMC brake component comprises a CMC brake disc.
10. The method of claim 1 , wherein the temperature is increased to a maximum temperature of substantially 2400° C.
11. The method of claim 1 , wherein the pressure is increased by actuating a punch to press against the mixture.
12. The method of claim 11 , wherein the electrical discharge is pulsed across the mixture through a graphite electrode coupled to the punch, a brass electrode coupled to the graphite electrode, and a copper plate coupled to the brass electrode.
13. The method of claim 1 , wherein the electrical discharge is pulsed at a cycle time of substantially 10 minutes.
14. The method of claim 1 , wherein the fibers are coated with an interphase layer.
15. The method of claim 14 , wherein the interphase layer comprises at least one of pyrolytic carbon or boron nitride.
16. A method of making a ceramic matrix composite (CMC) brake component, the method comprising:
applying a pressure to a mixture comprising ceramic powder and chopped fibers, wherein the ceramic powder comprises an average particle size ranging from micrometers to nanometers, wherein the chopped fibers are coated with an interphase layer;
pulsing an electrical discharge across the mixture to generate a pulsed plasma between particles of the ceramic powder;
generating the CMC brake component in response to increasing a temperature applied to the mixture from a first temperature to a second temperature using direct heating; and
reducing the temperature and the pressure applied to the CMC brake component.
17. The method of claim 16 , wherein the ceramic powder comprises at least one of SiC, B 4 C, or Si 3 N 4 .
18. The method of claim 16 , wherein the chopped fibers comprise at least one of chopped carbon fiber or chopped SiC fiber.
19. The method of claim 16 , wherein the interphase layer comprises at least one of pyrolytic carbon or boron nitride.