Particles of a refractory metal or a refractory-metal compound capable of decomposing or reacting into refractory-metal nanoparticles, elemental silicon, and an organic compound having a char yield of at least 60% by weight are combined to form a precursor mixture. The mixture is heating, forming a thermoset and/or metal nanoparticles. Further heating form a composition having nanoparticles of a refractory-metal silicide and a carbonaceous matrix. The composition is not in the form of a powder

A composite ceramic composition including a boron carbide phase and a method of forming the same. The composite ceramic composition includes a tungsten boride phase, a transition metal boride phase. The composite ceramic composition may also include a carbon disposed in solid solution with at least the tungsten boride phase and the transition metal boride phase. The transition metal boride phase may include a boride of at least one metal chosen from Cr, Nb, and Zr.

A silicon nitride ceramic material for a mobile phone rear cover and a preparation method therefor. The method comprises: using a mixture of a silicon source, a colorant, and a sintering aid as raw materials, mixing the raw material components, and performing shaping and sintering to obtain the silicon nitride ceramic material. The toughness of the silicon nitride ceramic material can reach more than 12 MPa.Math.m.sup.1/2; the thermal conductivity thereof can reach 40 to 70 W/m.Math.K; and a dielectric loss thereof is 10.sup.−4.

A ceramic matrix composite includes a substrate which contains a fibrous body formed from a silicon carbide fiber, and a matrix which is formed in the substrate, and which contains RE.sub.3Al.sub.5O.sub.12, RE.sub.2Si.sub.2O.sub.7, and the balance being an oxide of RE, Al, and Si, or RE.sub.2SiO.sub.5, where the RE is Y or Yb.

A composite magnetic material has a plurality of grains having a magnetic ferrite phase, grain boundaries surrounding the grains, and a plurality of nanoparticles disposed at the grain boundaries. The nanoparticles of the composite material are both magnetic and electrically insulating, having a magnetic flux density of greater than about 100 mT and an electrical resistivity of at least about 10.sup.8 Ohm-cm. Also provided is a method of making the composite material. The material is useful for making inductor cores of electronic devices.

A process of forming a sintered article includes heating a green portion of a tape of polycrystalline ceramic and/or minerals in organic binder at a binder removal zone to a temperature sufficient to pyrolyze the binder; horizontally conveying the portion of tape with organic binder removed from the binder removal zone to a sintering zone; and sintering polycrystalline ceramic and/or minerals of the portion of tape at the sintering zone, wherein the tape simultaneously extends through the removal and sintering zones.

The present disclosure provides a composite including a nitride sintered body having a porous structure and a semi-cured product of a heat-curable composition impregnated into the nitride sintered body, wherein a dielectric breakdown voltage obtainable after disposing the composite between adherends, heating and pressurizing the composite for 5 minutes under the conditions of 200° C. and 10 MPa, and further heating the composite for 2 hours under the conditions of 200° C. and atmospheric pressure, is greater than 5 kV.

A silicon nitride substrate includes silicon nitride and magnesium, in which when a surface of the silicon nitride substrate is analyzed with an X-ray fluorescence spectrometer under the specific Condition I, XB/XA is 0.8 or more and 1.0 or less.

One aspect of the present invention is a composite including: a porous boron nitride sintered body; and a resin filled in pores of the boron nitride sintered body, wherein the boron nitride sintered body has an average pore diameter of 3.5 μm or less.

A method of forming tungsten tetraboride, by combining tungsten and boron in a molar ratio of from about 1:6 to about 1:12, respectively, and firing the combined tungsten and boron in the hexagonal boron nitride crucible at a temperature of from about 1600 C to about 2000 C, to form tungsten tetraboride.