Provided is an aluminum nitride structure that includes a plurality of aluminum nitride particles, wherein aluminum nitride particles that are adjacent are bound to each other through a boehmite phase containing boehmite, and the porosity is 30% or less. Also provided is a method for producing an aluminum nitride structure that includes: obtaining a mixture by mixing an aluminum nitride powder with a solvent containing water; and pressurizing and heating the mixture under conditions of a pressure of 10 to 600 MPa and a temperature of 50 to 300° C.

A coated particle having excellent thermal expansion control and electrical insulation properties includes a core of a first inorganic compound containing a metal or semimetal element P; and a shell of a second inorganic compound containing a metal or semimetal element Q. The first inorganic compound satisfies 1, and the coated particles satisfy 2 and 3. 1: |dA(T)/dT| is ≥10 ppm/°C at T1 of -200° C. to 1,200° C. A is (an a-axis lattice constant of a crystal in the first inorganic compound)/(a c-axis lattice constant of a crystal in the first inorganic compound). 2: in XPS of a surface of each of the coated particles, a ratio of a number of atoms of Q contained in the shell to a number of atoms of P contained in the core t is 45 to 300. 3: an average particle diameter of each coated particle is 0.1 to 100 .Math.m.

The present disclosure provides processes for forming angular ceramic particles. In at least one embodiment, a process for forming angular ceramic particles includes providing a slurry having a ceramic raw material having alumina. The process includes atomizing the slurry into droplets and coating seeds comprising alumina with the droplets to form green pellets. The process includes sintering the green pellets to form sintered pellets. The process includes breaking the sintered pellets to form the angular ceramic particles comprising a sintered ceramic material. The angular ceramic particles can have an abrasion loss that is less than that of angular ceramic particles formed by crushing the green pellets prior to sintering.

A method for producing microencapsulated fuel pebble fuel more rapidly and with a matrix that engenders added safety attributes. The method includes coating fuel particles with ceramic powder; placing the coated fuel particles in a first die; applying a first current and a first pressure to the first die so as to form a fuel pebble by direct current sintering. The method may further include removing the fuel pebble from the first die and placing the fuel pebble within a bed of non-fueled matrix ceramic in a second die; and applying a second current and a second pressure to the second die so as to form a composite fuel pebble.

The present invention provides means capable of satisfactorily exhibit the properties inherent in the inorganic particle and the constituent material of the coating layer, such as obtaining high dispersibility and high mechanical properties in the coated particle that contains the inorganic particle having at least the inorganic substance capable of forming an inorganic oxide on a surface, and the coating layer with which the inorganic particle is coated. The present invention relates to a coated particle that contains an inorganic particle having at least an inorganic substance capable of forming an inorganic oxide on a surface, and a coating layer with which the inorganic particle is coated, in which the amount of the inorganic oxide per unit surface area of the inorganic particle does not exceed 0.150 mg/m.sup.2.

Thermoelectric (TE) nanocomposite material that includes at least one component consisting of nanocrystals. A TE nanocomposite material in accordance with the present invention can include, but is not limited to, multiple nanocrystalline structures, nanocrystal networks or partial networks, or multi-component materials, with some components forming connected interpenetrating networks including nanocrystalline networks. The TE nanocomposite material can be in the form of a bulk solid having semiconductor nanocrystallites that form an electrically conductive network within the material. In other embodiments, the TE nanocomposite material can be a nanocomposite thermoelectric material having one network of p-type or n-type semiconductor domains and a low thermal conductivity semiconductor or dielectric network or domains separating the p-type or n-type domains that provides efficient phonon scattering to reduce thermal conductivity while maintaining the electrical properties of the p-type or n-type semiconductor.

Methods of forming nanoceramic materials and components. The methods may include performing atomic layer deposition to form a plurality of nanoparticles, including forming a thin film coating over core particles, or sintering the nanoparticles in a mold. The nanoparticles can include a first material selected from a rare earth metal-containing oxide, a rare earth metal-containing fluoride, a rare earth metal-containing oxyfluoride or combinations thereof.

A method for producing microencapsulated fuel pebble fuel more rapidly and with a matrix that engenders added safety attributes. The method includes coating fuel particles with ceramic powder; placing the coated fuel particles in a first die; applying a first current and a first pressure to the first die so as to form a fuel pebble by direct current sintering. The method may further include removing the fuel pebble from the first die and placing the fuel pebble within a bed of non-fueled matrix ceramic in a second die; and applying a second current and a second pressure to the second die so as to form a composite fuel pebble.

A method of preparing a substrate having a wetting surface, including confirming the presence of an open, interconnected pore network in a ceramic substrate to be wetted with a first metal, filling the open, interconnected pore network with a second metal,

exuding the second metal to coat the surface of the substrate, and wetting the substrate with the first metal. The ceramic substrate is not decomposed by the first metal and the ceramic substrate is not decomposed by the second metal.

An ink of the formula: 60-80% by weight BaTiO.sub.3 particles coated with SiO.sub.2; 5-50% by weight high dielectric constant glass; 0.1-5% by weight surfactant; 5-25% by weight solvent; and 5-25% weight organic vehicle. Also a method of manufacturing a capacitor comprising the steps of: heating particles of BaTiO.sub.3 for a special heating cycle, under a mixture of 70-96% by volume N.sub.2 and 4-30% by volume H.sub.2 gas; depositing a film of SiO.sub.2 over the particles; mechanically separating the particles; incorporating them into the above described ink formulation; depositing the ink on a substrate; and heating at 850-900° C. for less than 5 minutes and allowing the ink and substrate to cool to ambient in N.sub.2 atmosphere. Also a dielectric made by: heating particles of BaTiO.sub.3 for a special heating cycle, under a mixture of 70-96% by volume N.sub.2 and 4-30% by volume H.sub.2 gas; depositing a film of SiO.sub.2 over the particles; mechanically separating the particles; forming them into a layer; and heating at 850-900° C. for less than 5 minutes and allowing the layer to cool to ambient in N.sub.2 atmosphere.