A dielectric ceramic composition includes a barium titanate (BaTiO.sub.3)-based base material main ingredient and an accessory ingredient, the accessory ingredient including dysprosium (Dy) and praseodymium (Pr) as first accessory ingredients. A content of the Pr satisfies 0.233 mol≤Pr≤0.699 mol, based on 100 mol of the barium titanate base material main ingredient.

A method includes molding a raw material powder containing a ceramic powder and a thermoplastic resin having a glass transition temperature higher than room temperature into a shape by isostatic pressing and in which a raw material powder slurry is prepared by adding the ceramic powder and the thermoplastic resin to a solvent so that the thermoplastic resin is 2% by weight or more and 40% by weight or less with respect to a total weight of the ceramic powder and the thermoplastic resin, a cast-molded body is to formed by wet-casting the raw material powder slurry into a shape, dried, and subjected to first-stage isostatic press molding at a temperature lower than the glass transition temperature of the thermoplastic resin, then this first-stage press-molded body is heated to the glass transition temperature of the thermoplastic resin or above, and warm isostatic press (WIP) molding is performed.

A SiC powder containing 70% by mass or more of a β-SiC, wherein in a volume-based cumulative particle size distribution measured by a laser diffraction method, a D50 is 8 to 35 μm and a D10 is 5 μm or more.

A manufacturing method of a ceramic electronic device includes forming a multilayer structure by stacking a plurality of stack units, each of the stack units having a structure in which a pattern of metal conductive paste is provided on a dielectric green sheet including a dielectric material, the metal conductive paste including a metallic material of which a main component is Ni and a co-material of which a main component is barium titanate, the metal conductive paste of each of the stack units being alternately shifted, and firing the multilayer structure. FWHM of the metallic material)/(FWHM of the co-material) is 0.550 or less. The FWHM is of a (111) face evaluated by powder X-ray diffraction. An average particle diameter of the metallic material before the firing is 120 nm or less.

A dielectric composition includes a main ingredient having a perovskite structure represented by ABO.sub.3, where A is at least one of Ba, Sr, and Ca and B is at least one of Ti, Zr, and Hf, and a first accessory ingredient. The first accessory ingredient comprises 0.1 mole or more of a rare earth element, 0.02 mole or more of Nb, and 0.25 mole or more and 0.9 mole or less of Mg, a sum of contents of the rare earth element and Nb is 1.5 mole or less.

A capacitor includes a stack and an external electrode located on a surface of the stack. The stack includes a plurality of dielectric layers and a plurality of internal electrode layers alternately stacked on one another. Crystal grains include first crystal grains having a small grain size and second crystal grains having a larger grain size. The first crystal grains satisfy 0.13 μm≤d1<0.30 μm, where d1 is the grain size of the first crystal grains. The second crystal grains satisfy 0.30 μm≤d2<0.50 μm, where d2 is the grain size of the second crystal grains. The second crystal grains have a higher additive element content than the first crystal grains.

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 paramagnetic garnet-type transparent ceramic characterized by being a sintered body of a terbium-containing composite oxide represented by formula (1) in which the linear transmittance at a wavelength of 1,064 nm at an optical path length of 15 mm is 83% or higher.
(Tb.sub.1-x-ySc.sub.xCe.sub.y).sub.3(Al.sub.1-zSc.sub.z).sub.5O.sub.12  (1)
(In the formula, 0<x<0.08, 0≤y≤0.01, 0.004<z<0.16.)

A fiber comprises a bulk material comprising: one or more of carbon, silicon, boron, silicon carbide, and boron nitride; and a metal or metal alloy whose affinity for oxygen is greater than that of the bulk material. At least a first portion of the metal or metal alloy is present at the entrance to grain boundaries at the surface of the fiber and within the fiber to a depth of at least 1 micron from the fiber surface. A method of improving a fiber comprises heating a fiber in an inert atmosphere to 900-1300 C for sufficient time to allow at least some of a metal or metal alloy, placed on the fiber, to diffuse and/or flow into and along grain boundaries to a depth of at least 1 micron. The metal or metal alloy has a greater affinity for oxygen than that of the fiber bulk material.

A dielectric composition includes a main phase and a Ca—Si—P—O segregation phase. The main phase includes a main component expressed by ABO.sub.3. “A” includes at least one selected from calcium and strontium. “B” includes at least one selected from zirconium, titanium, hafnium, and manganese. The Ca—Si—P—O segregation phase includes at least calcium, silicon, and phosphorus.