Abstract: Glass compositions containing oxygen and nitrogen prepared by melting admixture of magnesia and/or a magnesium silicate, silica and an aluminum nitride produced by reacting ammonia with aluminum oxide, have the formula:Mg.sub.x Si.sub.y Al O.sub.u N.sub.v (1)in which 0.25.ltoreq.x.ltoreq.2.50, 1.25.ltoreq.y.ltoreq.3.50, 3.75.ltoreq.u.ltoreq.10.50, and 0.05.ltoreq.v.ltoreq.0.75, with the proviso that 2x+4y+3=2u+3v; the subject glass compositions are thermally converted into vitroceramics having the same formula and including a single cordierite crystalline phase, which vitroceramics are well adapted for the production of composite shaped articles.

Abstract: Composite shaped articles, well adapted for aerospace applications, include a glass-ceramic and an effective amount of a reinforcing agent therefor, preferably a fibrous and ceramic reinforcing agent, such glass-ceramic matrix being based on silica, alumina, an alkaline earth metal oxide and a rare earth oxide, in the following proportions by weight relative to the total weight of the matrix:5%.ltoreq.MO.ltoreq.40%25%.ltoreq.SiO.sub.2 .ltoreq.70%15%.ltoreq.Al.sub.2 O.sub.3 .ltoreq.70%5%.ltoreq.rare earth oxide.ltoreq.70%wherein M represents an alkaline earth metal.

Abstract: A method of manufacturing a composite structure of ceramic material which is reinforced by refractory fibers, wherein a slip (11) is prepared from a synthetic resin having good wetting properties on ceramic material and fibers, embedding fibers (15) in the slip, eliminating the liquid phase from the slip by drying (16), eliminating the synthetic resin from the formed structure by heating, and sintering the fiber-impregnated ceramic material, wherein a synthetic resin solvent is incorporated in the slip, and wherein the fibers are inserted in the slip in the form of an assembly which is a sheet or roving, before the drying.

Abstract: An improved method of manufacturing a composite structure of ceramic material reinforced by refractory fibers is disclosed, whereby the fibers are first embedded in a slip of the ceramic material containing a synthetic resin with good ceramic and fiber wetting properties and a solvent of said resin, the liquid phase is thereafter eliminated from the slip by drying, the synthetic resin is driven from the formed structure by heating, and the fiber-reinforced ceramic material is sintered. The improvement consists in avoiding the use of costly aluminum-nitride powder by initially incorporating an aluminum powder in the slip along with the resin solvent and nitriding the powder in the structure, after drying and firing, but before sintering.

Abstract: The present invention relates to a ceramicized refractory composite and to a process for manufacturing same, wherein a multidirectional woven network is impregnated with a suspension of a ceramic powder and a fluid composition of a substance producing, under the action of heat treatment, a body of the same nature as the ceramic powder of said suspension.