TECHNICAL DESCRIPTION

Thermostructural composite materials retain their good mechanical properties even at high temperatures which make them suitable for constituting structural elements in particular in the fields of aviation and space, and in the field of friction, specifically for aircraft brake disks. Composite material parts are usually fabricated by making a fiber preform which is to constitute the fiber reinforcement of the composite material, and by densifying the preform with the matrix of the composite material. Proposals have already been made to introduce fillers into the pores of fiber structures /reinforcement of the composite material parts prior to densifying the fiber structures with the composite material matrix. The intended purposes are to reduce the fraction of the volume of the fiber structure that is represented by the pores in order to reduce the time taken by densification, and/or to impart special properties to the resulting composite material parts, and in particular to improve mechanical properties. Fillers consist of carbon or ceramic powders / of short fibers

INDUSTRIAL APPLICATIONS

An object of the invention is to overcome this difficulty so as to provide 3D fiber structures both for improving the properties of composite material parts obtained by densifying preforms made of such fiber structures and for improving the method of fabricating the parts. CNTs are grown on the refractory fibers of the substrate, after it has been impregnated by a composition comprising at least one catalyst for CNTs growth, so as to obtain a 3D structure made of refractory fibers and enriched in carbon nanotubes.

Different plies of fibers may be so processed before being joined together.

BENEFITS

• – retains the organization and cohesion qualities of a coherent 3D fiber structure;
  – reduction in the duration of densification (by liquid or gaseous process) because of the reduction in pore’s volume fraction without closing the pores;
  – reinforcement of  mechanical strength (higher filaments content);
  – improvement in resistance to wear; and  improved thermal conductivity;
  – Mrs. Bonnamy patent has been considered as relevant by examiners for the following invention: WO2005 013398 SNECMA and CEA