Abstract: A ceramic composite is provided comprising ceramic fibers and microparticles bound together as a porous matrix with a ceramic binder. The ceramic composite is particularly useful for transporting cryogenic fluids.

Abstract: Thermomechanical and thermo-oxidative stabilities in heterocycle or heterocycle sulfone resin composites are improved by forming four crosslinks at each addition polymerization site in the backbone of the resin using crosslinking functionalities.

Abstract: A hybrid metal webbed composite beam includes a metal I or T web section and a composite cap formed over and adhered to the I or T web. The beam incorporates the advantages of metals and composites in modern aerospace construction allowing thermoplastic welding of the beam to skins while having the strength of metal.

Abstract: Carbon-carbon grids for ion optics sets are thermomechanically stable under the extreme temperature changes that are experienced in ion thrusters. Screen, accelerator and decelerator grids are thermomechanically stable, lightweight, and resistant to erosion from ion sputtering and have extended lifetimes over conventional molybdenum grids.

Abstract: Crosslinkable, polyaromatic, polyether or polyester oligomers can have glass transition temperatures above 900.degree. F. while exhibiting desirable toughness for aerospace applications and ease of processing. A plurality (i.e. three or more) of generally linear aryl arms extend outwardly like spokes from a central aromatic hub through ether or ester linkages. Each spoke usually includes electronegative linkages, and is capped with one or two crosslinking functionalities (i.e. unsaturated hydrocarbon sites) which may be thermally or chemically activated to complete the advanced composite during curing. Among other methods, linear and multidimensional polyether oligomers are synthesized using nitrophthalic anhydride or halophthalic anhydride, dialcohols, or polyols, diamines, and suitable end caps.

Abstract: A La.sub.1-x Sr.sub.x Cr.sub.1-y Mn.sub.y O.sub.3 ceramic oxide gel obtainable by the process comprising the steps of:(a) providing a colloidal solution of polyhydroxy organic chelating agents selected from the group consisting of ethylene glycol and citric acid and metal salts selected from the group consisting of lanthanum, strontium, chromium, and manganese, each salt being present in an amount necessary to provide the stoichiometric amount of metal ions required in the ceramic oxide gel;(b) heating the colloidal solution to hydrolyze and polymerize the metal ions in the solution to a mixed metal oxide precursor of the ceramic oxide gel; and(c) adding organic acid, water or both to the precursor of the ceramic oxide gel to peptize the metal ions; and(d) heating the peptized precursor to evaporate solvent to form a thick, viscous, flexible, ductile, handleable gel that can be cast, extruded, or drawn; wherein x and y are independently 0 or 1.