A SiC powder containing 70% by mass or more of a β-SiC, wherein in a volume-based cumulative particle size distribution measured by a laser diffraction method, a D50 is 8 to 35 μm and a D10 is 5 μm or more.

A cutting element comprises a supporting substrate, and a cutting table attached to an end of the supporting substrate. The cutting table comprises inter-bonded diamond particles, and a thermally stable material within interstitial spaces between the inter-bonded diamond particles. The thermally stable material comprises a carbide precipitate having the general chemical formula, A.sub.3XZ.sub.n-1, where A comprises one or more of Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ac, Th, Pa, and U; X comprises one or more of Al, Ga, Sn, Be, Bi, Te, Sb, Se, As, Ge, Si, B, and P; Z comprises C; and n is greater than or equal to 0 and less than or equal to 0.75. A method of forming a cutting element, an earth-boring tool, a supporting substrate, and a method of forming a supporting substrate are also described.

To reduce size and mass of a nuclear reactor system, an integrated in-vessel shield separates the role of a neutron reflector and a neutron shield. Nuclear reactor system includes a pressure vessel including an interior wall and a nuclear reactor core located within the interior wall of the pressure vessel. Nuclear reactor core includes a plurality of fuel elements and at least one moderator element. Nuclear reactor system includes a reflector located inside the pressure vessel that includes a plurality of reflector blocks laterally surrounding the plurality of fuel elements and the at least one moderator element. Nuclear reactor system includes the in-vessel shield located on the interior wall of the pressure vessel to surround the reflector blocks. In-vessel shield is formed of two or more neutron absorbing materials. The two more neutron absorbing materials include a near black neutron absorbing material and a gray neutron absorbing material.

Embodiments are directed to the field of ceramics and relate to electron-emitting ceramics such as those which can be used as cathode material for electron emissions in space flight systems, for example. Embodiments specify an electron-emitting ceramic which has an improved temperature conductivity with a simultaneously continuous electron emission. The electron-emitting ceramic contains at least>70 vol. % C12A7 electride and a proportion of Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, In, Sn, Sb, Te, Tl, Pb, or Bi as metal and/or with Ti, wherein the proportion of the metals lies between>0 and<30 vol. %, and the ceramic has a density of at least 85% of the theoretical density of the ceramic and the ceramic contains 0 to maximally 10 vol. % production-specific impurities.

A carbon-metal/alloy composite material includes a composition represented by (1-a)Sn.sub.1-xM.sup.1.sub.x+aM.sup.2+cC, wherein: M.sup.1 includes one or more transition metals, metals, or metalloids; M.sup.2 includes one or more transition metals, metals, or metalloids; x is 0≦x≦1; a is 0≦a≦1; and c is 0<c≦99. A method of forming the carbon-metal/alloy composite material includes the steps of dissolving one or more precursor materials in a solvent to form a solution; adding an organic carbon forming precursor to the solution to form a mixture; heating the mixture in an autoclave reactor for a prescribed period of time; separating solids formed from the mixture after the heating; washing the separated solids with a washing solvent; and heating the washed solids under a non-oxidizing atmosphere to form the carbon-metal/alloy composite material.

A metal-ceramic composite for a fuel cell anode is disclosed. In the metal-ceramic composite, the content of the metal is greatly reduced and the intervals between the metal particles are maintained constant, achieving improved activity and conductivity. The metal-ceramic composite includes a metal catalyst raw material and a mixed-conductive ceramic. The metal catalyst raw material is present in an amount such that the content of the metal catalyst nanoparticles in the metal-ceramic composite is significantly lower than in conventional metal-ceramic composites. The presence of a small amount of the metal catalyst nanoparticles in the metal-ceramic composite minimizes the occurrence of stress resulting from a change in the volume of the metal catalyst and provides a solution to the problem of defects, achieving improved life characteristics. Also disclosed is a method for preparing the metal-ceramic composite.

An injection system comprises a fluid control member and a reciprocating member; wherein the fluid control member is configured to form a carbon composite-to-metal seal with the reciprocating member in response to application of a compressive force; the carbon composite comprising carbon and a binder containing one or more of the following: SiO.sub.2; Si; B; B.sub.2O.sub.3; a filler metal; or an alloy of the filler metal, and the filler metal comprising one or more of the following: aluminum; copper; titanium; nickel; tungsten; chromium; iron; manganese; zirconium; hafnium; vanadium; niobium; molybdenum; tin; bismuth; antimony; lead; cadmium; or selenium.

A precursor of an alumina sintered compact including aluminum, yttrium, and at least one metal selected from iron, zinc, cobalt, manganese, copper, niobium, antimony, tungsten, silver, and gallium. The aluminum content is 98.0% by mass or more as an oxide (Al.sub.2O.sub.3) in 100% by mass of the precursor of an alumina sintered compact; the yttrium content is 0.01 to 1.35 parts by mass as an oxide (Y.sub.2O.sub.3) based on 100 parts by mass of the content of the aluminum as an oxide; the total content of the metals selected from the foregoing group is 0.02 to 1.55 parts by mass as an oxide based on 100 parts by mass of the content of aluminum as an oxide; and the aluminum is contained as α-alumina. Also disclosed is an alumina sintered compact, and a method for producing an alumina sintered compact and for producing abrasive grains.

Disclosed herein are compounds, methods, and tools which comprise tungsten borides and mixed transition metal borides.

The present invention discloses a method for uniformly coating metal nanoparticles without a carbon impurity on an oxide ceramic powder surface, which includes the steps of putting grinded and mixed a metal organic material and oxide ceramic powder into a rotational reaction chamber, then bubbling oxidizing gas under a rotational and heating condition to oxidize the metal organic material into a metal oxide, and finally bubbling reducing gas to reduce the metal oxide into nanoparticles in a metallic state, so as to implement the uniform coating of the nanoparticles in the metallic state, and avoid coarsening and growing problems of nanoparticles led by a long-term coating reaction under a high temperature. The present invention has a simple method and a short preparation period, and the metal nanoparticles prepared are uniformly dispersed and have wide application prospects in multiple fields like catalytic materials and conductive ceramics.