Abstract: The present method of manufacturing a ceramic composite material, composed of matrix and reinforcing materials and an intermediate weak interfice material, creates a composite material particuarly intended for use at temperatures above 1400° C. and in an oxidizing environment. The matrix and reinforcing materials consist of the same or different ceramic oxides having a melting point above 1600° C. The interface material provides in combination with the matrix and reinforcing materials a stress field liable to micro aciding. The reinforcing material is immersed into a powder slurry containing carbon (C) and ZrO2 so as to be coated thereby and then dried. After which, the thus created composite material is subjected to green forming and densifying steps. Finally, the composite material undergoes a heat-treatment in air leaving a porous structure of the interface material.

Abstract: A plurality of elongate segments, joined along their abutting side edges, form a variable geometry exhaust nozzle for a turbojet engine afterburner. The segments may be planar or slightly curved. Each segment is devoid of metal on its "hot" side and has at least one elongate edge portion bent in not more than about 90.degree. towards the "cold" side of the segment at least along the longitudinal side facing the adjacent panel. The panels are mutually joined to form said segment under the intermediation of metal elements, preferably of U-shape, for gripping adjacent pairs of bent portions of the respective panel pairs, at least some of said metal elements and the respective edge portions thereof having holes for accommodating hinge shafts and/or actuation means such that on each segment a continuous ceramic surface, entirely free of metal, faces the hot exhaust gas flow of the engine.

Abstract: The present invention provides a method for preparing a ceramic mixed-oxide of at least two metals including mixing an alloy with a ceramic oxide. The alloy including a metal selected from the group consisting of aluminum, calcium, lithium, magnesium, silicon, titanium, yttrium, and zirconium. The alloy also includes an element that is to be present in the ceramic mixed-oxide. The element is different from the metal and is selected from the group consisting of aluminum, calcium, lithium, magnesium, a combination of magnesium and silicon, silicon, titanium, yttrium, and zirconium. The ceramic oxide includes a metal that is to be present in the ceramic mixed oxide. The alloy and ceramic oxide are co-milled. The mixed and co-milled alloy and ceramic oxide are reaction-sintered, thereby oxidizing the metal and element of the alloy to produce the ceramic mixed-oxide.

Abstract: A ceramic composite material comprising matrix material, reinforcing fibers and an intermediate interface material. The matrix material and reinforcing fibers consist of the same or different ceramic oxides having a melting point above 1600.degree. C. The interface material is applied as a coating on the fibers and consists of at least one ceramic oxide not exhibiting solid solubility, eutecticum below the temperature of manufacture or use or reactivity with any of the matrix or reinforcing materials. The matrix and reinforcing materials are substantially pure, and the combination fiber/interface material/matrix material is selected from the group consisting of: Al.sub.2 O.sub.3 /Al.sub.2 TiO.sub.5 /Al.sub.2 O.sub.3, YAG/Al.sub.2 TiO.sub.5 /Al.sub.2 O.sub.3, Al.sub.2 O.sub.3 /YAG/Al.sub.2 O.sub.3, Al.sub.2 O.sub.3 /SnO.sub.2 /Al.sub.2 O.sub.3, YAG/SnO.sub.2 /Al.sub.2 O.sub.3, Al.sub.2 O.sub.3 /mullite/Al.sub.2 O.sub.3, and mullite/ZrO.sub.2 /mullite.

Abstract: A method of manufacturing fiber-reinforced composites from a fibrous material, includes the steps of infiltrating the fibrous material with material from which a matrix is built up; preforming the infiltrated fibrous material into a green body against as shape-imparting body; encapsulating the preformed green body and shape-imparting body; consolidating and sintering the encapsulated green body by means of isostatic pressure sintering into an essentially dense composite body while preventing deformation of the green body with the shape-imparting body; and removing the encapsulated green body and shape-imparting body after isostatic pressure sintering.