A ceramic composite and a method of preparing the same are provided. The method of preparing the ceramic composite includes mixing an aluminum slag and a carbon accelerator to obtain a mixture and reacting the mixture at a temperature equal to or greater than 1600° C. in a nitrogen atmosphere to obtain a ceramic composite. The aluminum slag includes aluminum, oxygen, nitrogen, and magnesium. The weight ratio of the oxygen to the aluminum is 0.6 to 2. The weight ratio of the nitrogen to the aluminum is 0.1 to 1.2. The weight ratio of the magnesium to the aluminum is 0.04 to 0.2. The ceramic composite includes aluminum nitride accounting for at least 90 wt % of the ceramic composite.

The invention relates to a pre-impregnated fibre-reinforced composite material in laminar form, obtained impregnating a fibrous mass with a polymeric binder composition and intended to be subjected to successive forming and pyrolysis operations to produce a fibre-reinforced composite ceramic material. The polymeric binder composition is based on one or more resins chosen from the group consisting of siloxane resins and silsesquioxane resins, and can optionally comprise one or more organic resins. The polymeric binder composition is a liquid with viscosity between 55000 and 10000 mPas at temperatures between 50° C. and 70° C. The polymeric binder composition forms a polymeric binding matrix, not cross-linked or only partially cross-linked that fills the interstices of the fibrous mass. The invention also relates to a method for making said pre-impregnated fibre-reinforced composite material in laminar form. The invention further relates to a fibre-reinforced composite ceramic material, obtained by forming and subsequent pyrolysis of a pre-impregnated fibre-reinforced composite material, as well as a method for making said material.

A sintered body includes a crystal grain containing silicon nitride, and a grain boundary phase. If dielectric losses of the sintered body are measured while applying an alternating voltage to the sintered body and continuously changing a frequency of the alternating voltage from 50 Hz to 1 MHz, an average value ε.sub.A of dielectric losses of the sintered body in a frequency band from 800 kHz to 1 MHz and an average value ε.sub.B of dielectric losses of the sintered body in a frequency band from 100 Hz to 200 Hz satisfy an expression |ε.sub.A−ε.sub.B|≤0.1.

A surface-coated cutting tool including a tool substrate containing WC crystal grains and insulating grains, and a coating layer composed of a multiple nitride of Ti, Al, and V and disposed on the surface of the tool substrate. The multiple nitride is represented by a compositional formula: Ti.sub.aAl.sub.bV.sub.cN satisfying the following relations:
0.25≤a≤0.35,
0.64≤b≤0.74,
0<c≤0.06, and
a+b+c=1
wherein each of a, b, and c represents an atomic proportion. The coating layer is characterized by exhibiting a peak attributed to a hexagonal crystal phase and a peak attributed to a cubic crystal phase as observed through X-ray diffractometry.

A method for forming an oxidation protection system on a composite structure may comprise: applying a ceramic layer slurry to the composite structure, wherein the ceramic layer slurry comprises aluminum and silicon in a solvent or carrier fluid; and heating the composite structure in an environment comprising nitrogen gas and oxygen gas to form a ceramic layer on the composite structure, wherein the ceramic layer comprises aluminum nitride and alumina.

Provided is a method for manufacturing a composite body, the method including: a nitriding step of firing a boron carbide powder in a nitrogen atmosphere to obtain a fired product containing boron carbonitride; a sintering step of molding and heating a blend containing the fired product and a sintering aid to obtain a boron nitride sintered body including boron nitride particles and pores; and an impregnating step of impregnating the boron nitride sintered body with a resin composition, the composite body having the boron nitride sintered body and a resin filled in at least some of the pores of the boron nitride sintered body.

The present disclosure relates to a mold for glass forming, wherein the mold comprises a ceramic material, and wherein the ceramic material comprises aluminum nitride and hexagonal boron nitride, and wherein the ceramic material comprises from 50 to 80% by weight of aluminum nitride and from 20 to 50% by weight of hexagonal boron nitride, based on the total weight of the ceramic material. The present disclosure further relates to a process for using such molds to form curved glass plates.

A silicon nitride powder for sintering which, despite of its fine powdery form, shows a very small increase in the oxygen concentration with time and features excellent storage stability. The silicon nitride powder for sintering has a specific surface area of 5 to 30 m.sup.2/g, and is characterized by having a hydrophobicity (M value) of 30 or more and an increase in the oxygen concentration of 0.30% by mass or less after left to stand in the air of a humidity of 90% and 20° C. for 48 hours. The silicon nitride powder for sintering can be obtained by dry-pulverizing aggregated masses of the silicon nitride in an inert atmosphere in the presence of a silane coupling agent.

Organosilicon chemistry, polymer derived ceramic materials, and methods. Such materials and methods for making polysilocarb (SiOC) and Silicon Carbide (SiC) materials having 3-nines, 4-nines, 6-nines and greater purity. Vapor deposition processes and articles formed by those processes utilizing such high purity SiOC and SiC.

Disclosed are methods for forming boron nitride-containing aggregates that exhibit improved wear by attrition, and resulting filled polymers that exhibit significantly improved thermal conductivity. The boron nitride-containing aggregates are prepared according to a method that includes wet granulating boron nitride powder with a granulation solution to form wet boron nitride-containing granules; and drying the wet boron nitride-containing granules to cause evaporation of solvent in the granulation solution, thereby forming boron nitride-containing granules. Sintering achieves the desired boron nitride-containing aggregates.