Abstract: Methods for fabricating refractory metal scandate nanocomposite powders with homogeneous microstructured refractory metal grains and a uniform nanosized dispersion of scandia are provided. The powders prepared by the sol-gel methods have a spherical morphology, a narrow distribution of particle sizes and a very uniform dispersion of nanosized scandia particles joined to the tungsten grains. The powder particle sizes can range from nanometers to micrometers. The powders can be pressed into porous cathode structures that can be impregnated with emissive materials to produce high current density and long life cathodes for high-power terahertz vacuum electron devices. The sol-gel fabrication methods allow control over the materials, particle size, particle composition and pore size and distribution of the cathode structure by manipulation of the process parameters.

Abstract: Methods for fabricating refractory metal scandate nanocomposite powders with homogeneous microstructured refractory metal grains and a uniform nanosized dispersion of scandia are provided. The powders prepared by the sol-gel methods have a spherical morphology, a narrow distribution of particle sizes and a very uniform dispersion of nanosized scandia particles joined to the tungsten grains. The powder particle sizes can range from nanometers to micrometers. The powders can be pressed into porous cathode structures that can be impregnated with emissive materials to produce high current density and long life cathodes for high-power terahertz vacuum electron devices. The sol-gel fabrication methods allow control over the materials, particle size, particle composition and pore size and distribution of the cathode structure by manipulation of the process parameters.