Abstract: A preform for a carbon-carbon composite part (55) comprising multiple layers of fibrous mats (51, 52, 53) wherein each of the fibrous mats (51, 52, 53) comprises a random carbon-containing fibrous matrix (11) within which is distributed a polymeric binder and wherein adjacent mat layers (51, 52, 53) are bound together by additional polymer binder, stitching and interlocking tabs. The preform of the present invention may be an aircraft landing system brake disc. Also, a method of manufacturing a thick multi-layer composite preform.

Abstract: The present invention makes use of loose fibrous material (for instance, chopped fibers) as reinforcement matrix material in the manufacture of carbon-carbon composites. In accordance with this invention, a constraint fixture is provided which can be separated from the mold. The constraint fixture has an internal shape corresponding to the shape of a desired preform component, with the internal shape being defined by a bottom plate (2), an annular ejector plate (3, 3?), a inner wall (10), an outer wall (4), and an annular top plate (11, 11?). The constraint fixture is normally made of metal, porous ceramic, or carbon material. The constraint fixture of the mold holds the loose matrix materials (fibers, along with any fillers and/or additives). The mold assembly itself is segmented, so that the constraint, fixture and the loose fill materials in the fixture can be removed and subjected to further processing as a unit.