A ceramic electronic device includes: a multilayer structure in which each of dielectric layers and each of internal electrode layers are alternately stacked, a main component of the dielectric layers being ceramic, wherein a relationship of I.sub.A/I.sub.B>1.40 is satisfied in a TSDC (Thermally Stimulated Depolarization Currents) of temperature elevation rate of 10 degrees C./min under a condition of 130 degrees C., 5 V/m and a polarization of 30 min, when a peak current value on a lower temperature side in a temperature range of 130 degrees C. to 190 degrees C. is I.sub.A and a peak current value on a higher temperature side in a temperature range of 190 degrees C. to 280 degrees C. is I.sub.B.

Polycrystalline diamond compacts having interstitial diamonds and methods of forming polycrystalline diamond compact shaving interstitial diamonds with a quench cycle are described herein. In one embodiment, a polycrystalline diamond compact includes a substrate and a polycrystalline diamond body attached to the substrate. The polycrystalline diamond body includes a plurality of inter-bonded diamond grains that are attached to one another in an interconnected network of diamond grains and interstitial pockets between the inter-bonded diamond grains, and a plurality of interstitial diamond grains that are positioned in the interstitial pockets. Each of the plurality of interstitial diamond grains are attached to a single diamond grain of the interconnected network of diamond grains or other interstitial diamond grains.

An alumina sintered body including an inner layer in which alumina crystal grains contained have an average aspect ratio of 1.0 to 2.0 and an outer layer which covers at least a part of the inner layer from outside and in which alumina crystal grains contained have an average aspect ratio of more than 2.0, the alumina sintered body being free from silicon except unavoidable impurities.

A solid electrolyte includes partially stabilized zirconia in which a stabilizer forms a solid solution in zirconia. The partially stabilized zirconia includes at least monoclinic phase particles and cubic phase particles as crystal particles that configure the partially stabilized zirconia, and an abundance ratio of the monoclinic phase particle is 5 to 25% by volume. The partially stabilized zirconia includes stabilizer low-concentration phase particles of which concentration of the stabilizer at a particle center is equal to or less than 1 mol %, as the crystal particles. The stabilizer low-concentration phase particles have a particle-size distribution of number frequency thereof having a peak at which an average particle size is 0.6 to 1.0 m, and a particle size at 10% of a cumulative number is 0.5 m or greater, and of the overall low-concentration phase particles, 50% by volume or greater belong to the peak.

Material, use thereof and method to manufacture said material; wherein the material is porous and has: a total porosity ranging from 50% to 80%, in particular from 60% to 70%; interconnected pores; at least a part made of a hydrophilic material, in particular at least a part of the inner surfaces of the pores is made of a hydrophilic material; a permeability coefficient greater than 10.sup.6 m/sec; and wherein, in a given volume of the material, the total volume of pores with a diameter ranging from 0.1 m to approximately 0.3 nm is at least greater than 15% of the total volume of the pores, preferably it ranges from 15 to 36%.

An embodiment of a PCD insert comprises an embodiment of a PCD element joined to a cemented carbide substrate at an interface. The PCD element has internal diamond surfaces defining interstices between them. The PCD element comprises a masked or passivated region and an unmasked or unpassivated region, the unmasked or unpassivated region defining a boundary with the substrate, the boundary being the interface. At least some of the internal diamond surfaces of the masked or passivated region contact a mask or passivation medium, and some or all of the interstices of the masked or passivated region and of the unmasked or unpassivated region are at least partially filled with an infiltrant material.

A preparation method for a ceramic composite material, a ceramic composite material, and a wavelength converter. The preparation method comprises: preparing an aluminium salt solution and a fluorescent powder; dispersing the fluorescent powder into a buffer solution having a pH 4.5-5.5 to obtain a suspension; titrating the suspension with the aluminium salt solution to obtain a fluorescent powder coated with Al.sub.2O.sub.3 hydrate film; calcining the fluorescent powder coated with Al.sub.2O.sub.3 hydrate film to obtain a Al.sub.2O.sub.3-coated fluorescent powder; mixing aluminium oxide powder with a particle size of 0.1 m-1 m and aluminium oxide powder with a particle size of 1 m-10 m to obtain mixed aluminium oxide powder; mixing the Al.sub.2O.sub.3-coated fluorescent powder and the mixed aluminium oxide powder to obtain mixed powder, the Al.sub.2O.sub.3-coated fluorescent powder being present in 40%-90% by weight of the mixed powder; and pre-pressing and sintering the mixed powder to obtain the ceramic composite material.

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 m and an average width of 1 to 2 m, 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 polycrystalline cubic boron nitride, PCBN, material is provided. The material comprises between 30 and 90 weight percent cubic boron nitride (cBN) and a matrix material in which the cBN particles are dispersed. The matrix material comprises particles of an aluminium compound; the matrix material particles having a d50 when measured using a linear intercept technique of no more than 100 nm.

It is an object to provide a cubic boron nitride polycrystalline material excellent in toughness. A cubic boron nitride polycrystalline material containing fine cubic boron nitride which is granular, has a maximum grain size not greater than 100 nm, and has an average grain size not greater than 70 nm and at least one of plate-shaped cubic boron nitride in a form of a plate having an average major radius not smaller than 50 nm and not greater than 10000 nm and coarse cubic boron nitride which is granular, has a minimum grain size exceeding 100 nm, and has an average grain size not greater than 1000 nm is provided.