To be cost effective for strategic defense applications, materials exhibiting lightweight, high strength, dimensional stability and high % temperature capability must be ceramic and be easily formed to net shape without requiring grtnding to final configuration. A process is being demonstrated of forming and joining an integral high strength ceramic foam core to a smooth-surfaced skin (filament or whisker reinforced as necessary) so as to form net shape final components with smooth surfaces. The physical properties of these composites are being determined through testing of sample specimens by independent laboratories. The ceramic composites being fabricated and 'rested comprise a cellular foam core of high strength sn or sc ligaments that is skinned with a high strength sn or sc impervious smooth surface with or without filament reinforcement. Tensile strengths of sc filaments/ligaments have reached 700 kpsi with tensile moduli of 70 mpsi. The resulting skinned-core composite should exhibit high strength and stiffness, low weight, high temperature creep and oxidation resistance, low thermal expansion and excellent dimensional stability. The successful development of the ceramic composites would have potential application in gas turbine blades, nozzles and combustors; adiabatic diesel pistons, cylinder liners, heads and - valves; stirling engine hot components; and laser mirrors.
