A method of making a polycrystalline cubic boron nitride (PCBN), material is provided. The matrix precursor powder comprises an aluminium compound. The method comprises mixing matrix precursor powder comprising particles having an average particle size no greater than 250 nm, with between 30 and 40 volume percent of cubic boron nitride (cBN) particles having an average particle size of at least 4 μm, and then spark plasma sintering the mixed particles. The spark plasma sintering occurs at a pressure of at least 500 MPa, a temperature of no less than 1050° C. and no more than 1500° C. and a time of no less than 1 minute and no more than 3 minutes.

A multilayer electronic component includes a body including a plurality of dielectric layers, wherein, wherein a central portion of the capacitance formation portion is Aa, a boundary portion of the capacitance formation portion, adjacent to the cover portions, is Ab, a dielectric grain size corresponding to the top 50% of dielectric grains, in order of enlargement, from the smallest grain size, among a plurality of dielectric grains included in Aa, is D50a, and a dielectric grain size corresponding to the top 50% of dielectric grains, in order of enlargement, from the smallest grain size, among a plurality of dielectric grains included in Ab, is D50b, D50a satisfies 190 nm or less and D50b satisfies 120 nm or greater.

A method for producing an alumina sintered body, comprising: molding an alumina powder to obtain an alumina article, the alumina powder comprising alumina particles having a particle diameter of not less than 0.1 μm and less than 1 μm, and alumina particles having a particle diameter of not less than 1 μm and less than 100 μm; forming a carbon powder-containing layer on a surface of the alumina article to obtain a laminate body; and irradiating a surface of the carbon powder-containing layer of the laminate body with a laser light to form a transparent alumina sintered portion.

Provided is a ceramic composite material and a wavelength converter. The ceramic composite material includes: an alumina matrix, a fluorescent powder uniformly distributed in the alumina matrix, and scattering centers uniformly distributed in the alumina matrix, wherein the alumina matrix is an alumina ceramics, the scattering centers are alumina particles, the alumina particles each have a particle diameter of 1 μm to 10 μm, and the fluorescent powder has a particle diameter of 13 μm to 20 μm.

A composition which can be photopolymerized to make a part consisting of an oxide ceramic, or a hybrid part comprising at least one oxide ceramic and organic constituents, by a stereolithographic technique, the composition comprising: at least one photopolymerizable organic compound; at least one photo-initiator; at least one precursor of the oxide ceramic wherein the composition comprises from 25% to 70% by mass, relative to the total mass of the composition, of the at least one precursor of the oxide ceramic; and wherein the at least one precursor of the oxide ceramic comprises a mixture comprising a nanometric powder of the oxide ceramic, and at least one other element selected from a micrometric powder of the oxide ceramic and a pre-ceramic compound of the oxide ceramic.

Provided is a piezoelectric single crystal-polycrystal ceramic composite, a method of manufacturing the same, and piezoelectric and dielectric application components using the piezoelectric single crystal-polycrystal ceramic composite. The piezoelectric single crystal-polycrystal ceramic composite shows that complexation is carried out by the optimization of a ratio between grain size distributions of a piezoelectric single crystal and polycrystal ceramic grains, and a volume ratio of the contained piezoelectric single crystal so that mass production simultaneously with excellent piezoelectric characteristics of the piezoelectric single crystal can be realized, and the cost of production can be reduced, so the piezoelectric single crystal-polycrystal ceramic composite can be applied to piezoelectric and dielectric application components, like ultrasonic transducers, piezoelectric actuators, piezoelectric sensors, dielectric capacitors, electric field-generating transducers, and electric field and vibration-generating transducers, using the piezoelectric single crystal-polycrystal ceramic composite, and the piezoelectric single crystal-polycrystal ceramic composite can enhance piezoelectric characteristics and competitiveness in prices.

A substrate for mounting a light-emitting element according to the present disclosure contains a crystal particle of aluminum oxide and is composed of an alumina-based ceramic that contains 97% by mass or more of Al as a value of an Al.sub.2O.sub.3 equivalent among 100% by mass of all components thereof. An average value of an equivalent circle diameter of the crystal particle is 1.1 μm or greater and 1.8 μm or less and a standard deviation of an equivalent circle diameter thereof is 0.6 μm or greater and 1.4 μm or less.

A method of producing polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y (Y-358) whereby powders of yttrium (III) oxide, a barium (II) salt, and copper (II) oxide are pelletized, calcined at 850 to 950° C. for 8 to 16 hours, ball milled under controlled conditions, pelletized again and sintered in an oxygen atmosphere at 900 to 1000° C. for up to 72 hours. The polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y thus produced is in the form of elongated crystals having an average length of 2 to 10 μm and an average width of 1 to 2 μm, and embedded with spherical nanoparticles of yttrium deficient Y.sub.3Ba.sub.5Cu.sub.8O.sub.y having an average diameter of 5 to 20 nm. The spherical nanoparticles are present as agglomerates having flower-like morphology with an average particles size of 30 to 60 nm. The ball milled polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y prepared under controlled conditions shows significant enhancement of superconducting and flux pinning properties.

A method of forming a superabrasive component for an earth-boring tool comprises disposing a first volume of particulate superabrasive material on a surface of a base structure. A first carbon-containing precursor material is deposited onto the first volume of unbonded particulate superabrasive material. An energy beam is directed onto the first carbon-containing precursor material to form a first volume of bonded polycrystalline superabrasive material having carbon-carbon atomic bonds between adjacent particles of the first volume of particulate superabrasive material. The method may be repeated to form a superabrasive component with multiple volumes of bonded polycrystalline superabrasive material. Additional methods of forming a superabrasive component, a superabrasive component, and an earth-boring tool are also described.

A cBN sintered material comprising cBN particles and a binder phase, in which the binder phase contains AlN and AlB.sub.2, a content proportion of cBN particles is 70 to 97 vol %, cBN sintered material has a volume resistivity up to 5×10.sup.−3 Ωcm, a rate of a peak intensity derived from Al with respect to a peak intensity derived from cBN particles is less than 1.0%, cBN particles include fine particles and coarse particles, coarse particles optionally include ultra-coarse particles, with respect to the entire cBN particles, a content proportion α of fine particles is from 10 vol %, a content proportion β of coarse particles is from 30 vol %, a content proportion γ of ultra-coarse particles is 25 vol % or less, and a total of the content proportion α of fine particles and the content proportion β of coarse particles is 50 to 100 vol %.