A disclosure is provided for methods to prepare high-strength and high-toughness partially stabilized zirconia (PSZ) materials by incorporating a starting ceramic powder in which the stabilizing oxide agent is pre-alloyed with the zirconia material powder. The ceramic powder is pre-stabilized so there is little or no remaining free stabilizing oxide, thereby resulting in an improved material that is more convenient to process using conventional ceramic processing techniques.

A ferrite sintered magnet 100 comprises M-type ferrite crystal grains 4 having a hexagonal structure, two-crystal grain boundaries 6a formed between two of the M-type ferrite crystal grains 4, and multiple-crystal grain boundaries 6b surrounded by three or more of the M-type ferrite crystal grains 4. This ferrite sintered magnet 100 contains at least Fe, Ca, B, and Si, and contains B in an amount of 0.005 to 0.9 mass % in terms of B.sub.2O.sub.3, the two-crystal grain boundaries 6a and the multiple-crystal grain boundaries 6b contain Si and Ca, and in a cross-section parallel to a c-axis of the ferrite sintered magnet, when the number of multiple-crystal grain boundaries 6b having a maximum length of 0.49 to 5 μm per cross-sectional area of 76 μm.sup.2 is N, N is 7 or less.

A dry backfill for producing a basic molded heavy-clay refractory product, to such a product and a method for producing the same, to a lining of an industrial furnace, and to an industrial furnace.

A phosphor plate including: a complex containing an α-sialon phosphor and a sintered body containing spinel represented by a general formula M.sub.2xAl.sub.4-4xO.sub.6-4x (where M represents at least one of Mg, Mn, and Zn, and 0.2<x<0.6). In addition, there is provided a light emitting device including: a group III nitride semiconductor light emitting element; and the phosphor plate provided on one surface of the group III nitride semiconductor light emitting element. Further, there is provided a method for manufacturing the phosphor plate.

The present invention relates to a method for preparing a fully ceramic capsulated nuclear fuel material containing three-layer-structured isotropic nuclear fuel particles coated with a ceramic having a composition which has a higher shrinkage than a matrix in order to prevent cracking of ceramic nuclear fuel, wherein the three-layer-structured nuclear fuel particles before coating is included in the range of between 5 and 40 fractions by volume based on after sintering. More specifically, the present invention provides a composition for preparing a fully ceramic capsulated nuclear fuel containing three-layer-structured isotropic particles coated with the substance which includes, as a main ingredient, a silicon carbine derived from a precursor of the silicon carbide wherein a condition of ΔL.sub.c>ΔL.sub.m at normal pressure sintering is created, where the sintering shrinkage of the coating layer of the three-layer-structured isotropic nuclear fuel particles is ΔL.sub.c and the sintering shrinkage of the silicon carbide matrix is ΔL.sub.m; material produced therefrom; and a method for manufacturing the material. The residual porosity of the fully ceramic capsulated nuclear fuel material is 4% or less.

A member for a plasma processing device of the present disclosure is a member for a plasma processing device made of ceramics and having a shape of a cylindrical body with a through hole in an axial direction. The ceramics is mainly composed of aluminum oxide, and has a plurality of crystal grains and a grain boundary phase that is present between the crystal grains. An inner peripheral surface of the cylindrical body has an arithmetic average roughness Ra of 1 μm or more and 3 μm or less, and an arithmetic height Rmax of 30 μm or more and 130 μm or less.

Provided is a dielectric ceramic composition including a first component and a second component, wherein the first component comprises an oxide of Ca of 0.00 mol % to 35.85 mol % an oxide of Sr of 0.00 mol % to 47.12 mol %, an oxide of Ba of 0.00 mol % to 51.22 mol %, an oxide of Ti of 0.00 mol % to 17.36 mol %, an oxide of Zr of 0.00 mol % to 17.36 mol %, an oxide of Sn of 0.00 mol % to 2.60 mol %, an oxide of Nb of 0.00 mol % to 35.32 mol %, an oxide of Ta of 0.00 mol % to 35.32 mol %, and an oxide of V of 0.00 mol % to 2.65 mol %, and the second component includes at least (a) an oxide of Mn of 0.005% by mass to 3.500% by mass and (b) an oxide of Cu and/or an oxide of Ru.

Provided is a ZrO.sub.2—CaO—C based refractory material which is capable of maintaining high adhesion resistance over a long period of time, while exhibiting significant slaking resistance, and suppressing self-fluxing, i.e., exhibiting corrosion-erosion resistance. The refractory material comprises a CaO—ZrO.sub.2 composition containing a CaO component in an amount of 40% by mass to 60% by mass, wherein a mass ratio of the CaO component to a ZrO.sub.2 component is 0.67 to 1.5, and wherein the CaO—ZrO.sub.2 composition includes a eutectic microstructure of CaO crystals and CaZrO.sub.3 crystals, wherein a width of each of the CaO crystals observable in a cross-sectional microstructure is 50 μm or less.

A ceramic electronic device includes a multilayer structure in which each of a plurality of dielectric layers and each of a plurality of internal electrode layers are alternately stacked, a main component of the plurality of dielectric layers being a ceramic having a perovskite structure expressed by a general formula ABO.sub.3. At least one of crystal grains of the plurality of dielectric layers has a core-shell structure. A dispersion of atomic displacement amounts between B site atoms and oxygen atoms of a shell of the core-shell structure is larger than a dispersion of atomic displacement amounts between B site atoms and oxygen atoms of a core of the core-shell structure.

A plasma processing device member according to the disclosure includes a base material and a film formed of a rare-earth element oxide, or a rare-earth element fluoride, or a rare-earth element oxyfluoride, or a rare-earth element nitride, the film being disposed on at least part of the base material. The film includes a surface to be exposed to plasma, the surface having an arithmetic mean roughness Ra of 0.01 μm or more and 0.1 μm or less, the surface being provided with a plurality of pores, and a value obtained by subtracting an average equivalent circle diameter of the pores from an average distance between centroids of adjacent pores is 28 μm or more and 48 μm or less. A plasma processing device according to the disclosure includes the plasma processing device member described above.