Surface-aided melt infiltration for producing a ceramic matrix composite

1. A method of melt infiltration for producing a ceramic matrix composite, the method comprising:

applying a surface slurry onto one or more outer surfaces of an impregnated porous preform comprising a framework of ceramic fibers loaded with particulate matter, the surface slurry comprising a solvent and particulate solids;

drying the surface slurry to form a porous layer comprising the particulate solids on the one or more outer surfaces; and

after forming the porous layer, immersing an end portion of the impregnated porous preform into a molten material, the end portion including at least part of the porous layer, the molten material being infiltrated into the impregnated porous preform from the end portion,

wherein the porous layer serves as a wick to transport the molten material over the one or more outer surfaces, thereby enabling melt infiltration of the impregnated porous preform from other portion of the porous layer not immersed in the molten material.

2. The method of claim 1 , wherein applying the surface slurry comprises dip coating, solution casting, spray coating and/or brushing on.

3. The method of claim 1 , wherein the surface slurry covers only a portion of the one or more outer surfaces.

4. The method of claim 1 , wherein the surface slurry covers an entirety of the one or more outer surfaces.

5. The method of claim 1 , wherein the porous layer comprises a thickness of from about 0.1 mm to about 1 mm.

6. The method of claim 1 , further comprising incorporating one or more reinforcement structures into the surface slurry prior to application to the one or more outer surfaces.

7. The method of claim 6 , wherein the one or more reinforcement structures comprises a woven fabric comprising a polymer.

8. The method of claim 1 , wherein, prior to infiltration of the molten material, the porous layer comprises a loading of the particulate solids of from about 30 vol. % to about 60 vol. %, the particulate solids including ceramic particles comprising a ceramic selected from the group consisting of: silicon carbide, silicon nitride, alumina and aluminosilicate.

9. The method of claim 8 , wherein the particulate solids further comprise one or more reactive elements selected from the group consisting of carbon, molybdenum, tungsten and titanium.

10. The method of claim 1 , wherein, prior to infiltration of the molten material, the impregnated porous preform comprises a loading of the particulate matter of from about 40 vol. % to about 60 vol. %, the particulate matter including ceramic particles selected from the group consisting of silicon carbide, silicon nitride, alumina and aluminosilicate, and the particulate matter further comprising one or more reactive elements in an amount from about 2 wt. % to about 12 wt. %.

11. The method of claim 1 , further comprising, prior to infiltrating the molten material, machining the porous layer.

12. The method of claim 1 , further comprising, after infiltration of the molten material, cooling the molten material to form a composite body including a ceramic coating thereon,

wherein the ceramic fibers comprise a ceramic selected from the group consisting of: silicon carbide, silicon nitride, alumina, and aluminosilicate.

13. The method of claim 12 , further comprising, after cooling, machining the ceramic coating.

14. The method of claim 12 , wherein the ceramic coating comprises a ceramic selected from the group consisting of: carbide, nitride, silicide and boride.

15. The method of claim 12 , wherein the ceramic coating further comprises silicon.