Process for manufacturing a ceramic composite material part by pressurized injection of a loaded slurry into a porous mould
A method of fabricating a composite material part includes injecting under pressure a slurry containing a powder of refractory ceramic particles into a fiber texture; and draining the liquid of the slurry that has passed through the fiber texture, while retaining the powder of refractory ceramic particles within the texture to obtain a fiber preform filled with refractory ceramic particles. The injection tooling includes a porous material mold including an internal housing in which the fiber texture is placed, the slurry being injected into the fiber texture via an injection port in the injection tooling and leading into the internal housing of the mold. The tooling includes a rigid material enclosure in which the porous material mold is held while the slurry is injected under pressure and while the liquid of the slurry is drained, the liquid of the slurry being discharged via a vent present in the enclosure.
1. A method of fabricating a composite material part, the method comprising:
forming a fiber texture from refractory ceramic fibers;
placing the fiber texture in injection tooling;
injecting under pressure a slurry containing a powder of refractory ceramic particles into the fiber texture;
draining liquid of the slurry that has passed through the fiber texture, while retaining the powder of refractory ceramic particles within said texture so as to obtain a fiber preform that is filled with refractory ceramic particles;
drying the fiber preform;
unmolding the fiber preform; and
sintering the refractory ceramic particles present in the fiber preform in order to form a refractory matrix in said preform;
wherein the injection tooling comprises a mold of porous material including an internal housing in which the fiber texture is placed and enclosed, the slurry being injected into the fiber texture via at least one injection port present in the injection tooling passing through the mold of porous material and leading into the internal housing of the porous material mold, the tooling further comprising an enclosure made of rigid material in which the porous material mold is held while injecting the slurry under pressure and while draining the liquid of said slurry, the liquid of the slurry being discharged via at least one vent present in the rigid material enclosure.
2. A method according to claim 1 , wherein the porous material mold presents a size smaller than the inside volume of the rigid material enclosure, and wherein the volume present between the porous material mold and the rigid material enclosure is filled in with a porous medium.
3. A method according to claim 2 , wherein the porous medium is constituted at least by sand or a foam.
4. A method according to claim 2 , wherein the empty volume present in the porous medium is greater than the volume of the liquid phase of the slurry injected into the fiber texture.
5. A method according to claim 1 , wherein the mold is made of a material selected from one of the following materials: porous resin and plaster.
6. A method according to claim 1 , wherein, during the forming of the fiber texture, yarns are woven with a three-dimensional or multilayer weave.
7. A method according to claim 1 , wherein yarns of the fiber texture are made of fibers constituted by one or more of the following materials: alumina; mullite; silica; an aluminosilicate; a borosilicate; silicon carbide; and carbon.
8. A method according to claim 1 , wherein the refractory ceramic particles are made of a material selected from: alumina; mullite; silica; an aluminosilicate; an aluminophosphate; zirconia; a carbide; a boride; and a nitride.
9. A method according to claim 1 , wherein the resulting part made of composite material constitutes a turbine engine blade.
10. A method according to claim 1 , wherein the mold of porous material surrounds the entire fiber preform.
11. A method according to claim 1 , wherein the mold of porous material surrounds the entire fiber preform to permit draining liquid of the slurry that has passed through the fiber texture via any point of an interface between the fiber texture and the mold of porous material.
12. A method according to claim 1 , wherein the enclosure made of rigid material surrounds, and is spaced apart from, the entire mold of porous material during the injecting and draining.
13. A method according to claim 1 , wherein a volume present between the enclosure made of rigid material and the mold of porous material is filled with a porous medium.
14. A method according to claim 13 , wherein the porous medium is sand or foam.
15. A method according to claim 1 , wherein the rigid material is plastic or metal.
16. A method according to claim 1 , wherein the porous material mold is made up of two portions, each having a respective recess that defines the internal housing of the porous material mold.