This disclosure relates to a high cBN content polycrystalline cubic boron nitride, PCBN, material. The binder matrix material comprises 19 to 50 wt. % chromium, or a compound thereof.

A thermoelectric conversion material includes Mg.sub.2Si.sub.xSn.sub.1−x (where 0.3≤X≤1) and a boride containing one or two or more metals selected from titanium, zirconium, and hafnium. Further, it is preferable that the boride is one or two or more selected from TiB.sub.2, ZrB.sub.2, and HfB.sub.2.

In some embodiments, a ceramic armor product includes: a ceramic powder; an at least one metal-based additive; and a density of 4.3-4.7 g/cc, wherein the ceramic armor product is substantially lacking grain orientation. In some embodiments, a ceramic armor product, includes: a ceramic powder, wherein the ceramic powder is titanium diboride (TiB2); an at least one metal-based additive, wherein the at least one metal based additive comprises elements ranging from atomic numbers 21 through 30, 39 through 51, and 57 through 77; and a density of 4.3-4.7 g/cc, wherein the ceramic armor product is substantially lacking grain orientation.

Nuclear fuel structures and methods for fabricating are disclosed herein. The nuclear fuel structure includes a plurality of fibers arranged in the structure and a multilayer fuel region within at least one fiber of the plurality of fibers. The multilayer fuel region includes an inner layer region made of a nuclear fuel material, and an outer layer region encasing the nuclear fuel material. A plurality of discrete multilayer fuel regions may be formed over a core region along the at least one fiber, the plurality of discrete multilayer fuel regions having a respective inner layer region of nuclear fuel material and a respective outer layer region encasing the nuclear fuel material. The plurality of fibers may be wrapped around an inner rod or tube structure or inside an outer tube structure of the nuclear fuel structure, providing both structural support and the nuclear fuel material of the nuclear fuel structure.

A method of making a ceramic composite component includes providing a fibrous preform or a plurality of fibers, providing a first plurality of particles, coating the first plurality of particles with a coating to produce a first plurality of coated particles, delivering the first plurality of coated particles to the fibrous preform or to an outer surface of the plurality of fibers, and converting the first plurality of coated particles into refractory compounds. The first plurality of particles or the coating comprises a refractory metal.

A cubic boron nitride sintered material includes: to 98 volume % of cubic boron nitride grains; and a binder phase, wherein the binder phase includes at least one selected from a group consisting of one or more first compounds and a solid solution originated from the first compounds, the cubic boron nitride grains include, on number basis, more than or equal to 50% of cubic boron nitride grains each having an equivalent circle diameter of more than 0.5 μm, and includes, on number basis, less than or equal to 50% of cubic boron nitride grains each having an equivalent circle diameter of more than 2 μm, and when a mass of the cubic boron nitride grains is assumed as 100 mass %, a total content of lithium, magnesium, calcium, strontium, beryllium, and barium in the cubic boron nitride grains is less than 0.001 mass %.

Polycrystalline cubic boron nitride, PCBN, material and methods of making PCBN. A method includes providing a matrix precursor powder comprising particles having an average particle size no greater than 250 nm, providing a cubic boron nitride, cBN, powder comprising particles of cBN having an average particle size of at least 0.2 intimately mixing the matrix precursor powder and the cBN powder, and sintering the intimately mixed powders at a temperature of at least 1100° C. and a pressure of at least 3.5 GPa to form the PCBN material comprising particles of cubic boron nitride, cBN dispersed in a matrix material.

A center flare tip assembly (16) and plenum flare tip assembly (18) with arms (20), having the outside of the center flare tip assembly (16), both inside and outside of the tips (18), the outside of the arms (20), and/or adjacent features of the flare tip (12) are covered with a high emissivity thermal layer (14) with an emissivity greater than 0.85. This reduces flare metal temperatures by thirty percent (30%) or greater, and increases flare life by two (2) to five (5) times current life.

This disclosure relates to polycrystalline cubic boron nitride material with cBN particles in a metal matrix comprising zirconium nitride and/or vanadium nitride precipitates or grains.

Polycrystalline cubic boron nitride, PCBN, material and methods of making PCBN. A method includes providing a matrix precursor powder comprising particles having an average particle size no greater than 250 nm, providing a cubic boron nitride, cBN, powder comprising particles of cBN having an average particle size of at least 0.2 μm, intimately mixing the matrix precursor powder and the cBN powder, and sintering the intimately mixed powders at a temperature of at least 1100° C. and a pressure of at least 3.5 GPa to form the PCBN material comprising particles of cubic boron nitride, cBN dispersed in a matrix material.