Abstract: Ceramic materials are found to be capable of superplastic forming at moderate temperatures with a high strain rate when the forming is performed in the presence of an electric current such as that produced by spark plasma sintering.

Abstract: High-density composites of alumina and titania with nano-sized grains are prepared from aluminum titanate without the need to use nano-sized powder as a starting material. The preparation is achieved by high-energy ball milling of the aluminum titanate followed by sintering at elevated temperature and pressure. The aluminum titanate can be prepared from micron-sized alumina and titania particles through plasma jet processing.

Abstract: Optical windows for protecting infrared sensing instruments are manufactured from nano-sized crystallites by compressing the crystallites into a continuous mass under high pressure in the presence of a pulsed electric current, preferably one produced by spark plasma sintering. The resulting materials have excellent optical and mechanical properties that make them favorable as replacements for the conventional single-crystal sapphire.

Abstract: Composites of ceramic materials, notably alumina or metal oxides in general, with single-wall carbon nanotubes are consolidated by electric field-assisted sintering to achieve a fully dense material that has an unusually high fracture toughness compared to the ceramic alone, and also when compared to composites that contain multi-wall rather than single-wall carbon nanotubes, and when compared to composites that are sintered by methods that do not include exposure to an electric field.

Abstract: Densified composites of silicon nitride, silicon carbide, and boron nitride that exhibit high creep resistance are obtained by sintering a mixture of amorphous powders of silicon nitride, silicon carbide, and boron nitride in the presence of an electric field under high pressure. The grain size in the resulting composite is less than 100 nanometers for all components of the composite, and the composite exhibits high creep resistance.

Abstract: A highly dense composite of a ceramic material and silicon carbide whiskers with grain sizes in the nano-sized range is formed by mechanical activation of the ceramic material in the form of a nano-sized powder, followed by compressing a mixture of the mechanically activated ceramic material and silicon carbide whiskers into a fused mass while passing an electric current through the mixture, preferably by electric field-assisted sintering. The nano-sized grains in the final microstructure provide the composite with superior mechanical properties, notably strength and toughness.

Abstract: Composite materials formed of a matrix of fused ceramic grains with single-wall carbon nanotubes dispersed throughout the matrix and a high relative density, notably that achieved by electric field-assisted sintering, demonstrate unusually high electrical conductivity in combination with high-performance mechanical properties including high fracture toughness. This combination of electrical and mechanical properties makes these composites useful as electrical conductors in applications where high-performance materials are needed due to exposure to extreme conditions such as high temperatures and mechanical stresses.