MATERIALES COMPUESTOS TERMOESTRUCTURALES CON REFUERZOS DE FIBRAS DE CARBONO O REVESTIDAS DE CARBONO, QUE TIENEN UNA RESISTENCIA INCREMENTADA A LA OXIDACION

LA MATRIZ DEL MATERIAL COMPOSITE SE REALIZA EN EL INTERIOR DEL REFUERZO FIBROSO POR INFILTRACION QUIMICA EN FASE VAPOR DE FORMA SECUENCIADA. CADA SECUENCIA ELEMENTAL DE MATRIZ CONSTA DE UNA CAPA RELATIVAMENTE FLEXIBLE Y UNA CAPA CERAMICA RELATIVAMENTE RIGIDA Y TIENE UN ESPESOR CRECIENTE A PARTIR DE LAS FIBRAS DE REFUERZO, SIENDO EL ESPESOR DE AL MENOS LA PRIMERA SECUENCIA DEPOSITADA SUFICIENTEMENTE PEQUEÑO PARA FORRAR LAS FIBRAS DE FORMA ESENCIALMENTE INDIVIDUAL. LAS CAPAS FLEXIBLES SE REALIZAN EN UN MATERIAL ANISOTROPICO CON SUFICIENTE CAPACIDAD DE DEFORMACION ELASTICA EN CIZALLAMIENTO Y TRANSVERSAL, Y SU ESPESOR DEBE SER LO BASTANTE GRANDE, CONSERVANDO LA MATRIZ UN CARACTER PRINCIPALMENTE CERAMICO, PARA ABSORBER LAS DILATACIONES DIFERENCIALES DE LOS CONSTITUYENTES DEL MATERIAL COMPOSITE EN LA FASE DE ELABORACION DE ESTE SIN INDUCIR LA EXISTENCIA DE UNA RED DE FISURACION INICIAL. PCT No. PCT/FR96/01951 Sec. 371 Date Jun. 12, 1998 Sec. 102(e) Date Jun. 12, 1998 PCT Filed Dec. 6, 1996 PCT Pub. No. WO97/21645 PCT Pub. Date Jun. 19, 1997The matrix of the composite material is made in sequenced manner by chemical vapor infiltration within fiber reinforcement. Each elementary sequence of the matrix comprises a relatively flexible layer and a relatively rigid ceramic layer, and the sequences are of thicknesses that increase going away from the reinforcing fibers, with the thickness at least of the first-deposited sequence being selected to be sufficiently small for the fibers to be coated in essentially individual manner. The flexible layers are made of an anisotropic material having sufficient capacity for elastic deformation in shear and transversely, and although a mainly ceramic character is conserved for the matrix, the thickness of the flexible layers is nevertheless selected to be sufficiently large to be capable of absorbing differential expansion of the components of the composite material while it is being made without inducing the existence of an initial network of cracks.