Method for the production of a part made from a composite material, by means of the injection of powder into a fibrous reinforcement with drainage through a composite filtration layer

A process for manufacturing a composite material part comprising:

• forming a fibrous texture from refractory ceramic fibres,
• placing the fibrous texture in a mould having at least one injection port and at least one evacuation port, a filtration layer being interposed between the fibrous texture and said at least one evacuation port, the filtration layer comprising a partially densified fibrous structure,
• pressure injecting a slurry containing a powder of refractory ceramic particles into the fibrous texture,
• draining by the filtration layer the solvent of the slurry having passed through the fibrous texture and retaining the powder of refractory ceramic particles within said texture by the filtration layer so as to obtain a fibrous preform comprising at least the fibrous texture filled with refractory ceramic particles and the filtration layer, the solvent being discharged through said at least one discharge port,
• heat treating the refractory ceramic particles present in the fibrous texture of the preform in order to form a composite material part comprising at least said fibrous texture densified by a refractory ceramic matrix and the filtration layer.