The present invention discloses magnesia and a method for manufacturing same, wherein the magnesia can be produced into granules of various shapes and sizes and can be improved in moisture resistance with the formation of a moisture resistant surface oxide layer by donor addition and then thermal treatment. The magnesia according to the present invention comprises a MgO granule; and a surface oxide layer formed on a surface of the MgO granule and a composition of the surface oxide layer is different from a composition of an inside of the MgO granule.

An iron oxide powder which has an aluminum content of from 10 mol % to 80 mol % (inclusive), and which is composed of porous structures that have a diameter of from 0.3 μm to 2 μm (inclusive).

A composite ceramic with improved mechanical performance and a preparation method therefor. The composite ceramic comprises fluorescent powder, a ceramic matrix, and an optional sintering aid. The weight ratio of the fluorescent powder to the ceramic matrix is from 3:17 to 9:1, and the relative density of the composite ceramic is greater than 95%. The preparation method comprises using core shell-structured coated fluorescent powder as a raw material, and ball-milling and sintering the raw material to obtain the composite ceramic.

The invention relates to a refractory product, a batch composition for producing said product, a method for producing the product and the use of the refractory product.

A ceramic electronic component that includes a plurality of ceramic layers which are stacked together, and an internal conductor layer disposed between two adjacent ceramic layers among the plurality of ceramic layers, and in which a ceramic layer that is adjacent to the internal conductor layer includes a plurality of pores.

A sensor element of a gas sensor includes: an element base which is a ceramic structured body including a detection part of detecting a target measurement gas component; and a protective layer which is a porous layer provided in at least a part of an outermost peripheral portion of the element base, wherein in the protective layer, numerous convex parts each having a size of 1.0 μm or less and made up of ceramic microparticles with diameters of 10 nm to 1.0 μm are discretely formed around numerous ceramic coarse grains having diameters of 5.0 μm to 40 μm, the respective ceramic coarse grains are connected to each other directly or via the ceramic microparticle, and a degree of porosity of the protective layer is 5% to 50%.

A sensor element of a gas sensor includes: an element base which is a ceramic structured body including a detection part of detecting a target measurement gas component; an outer protective layer which is a porous layer provided in at least a part of an outermost peripheral portion of the element base; and an inner protective layer which is a porous layer having a degree of porosity of 30% to 85%, which is larger than a degree of porosity of the outer protective layer, inside the outer protective layer, wherein an average fine pore diameter of the inner protective layer is equal to or larger than 0.5 μm and equal to or smaller than 5.0 μm.

The present invention provides a method for producing a powder containing zirconia particles and a fluorescent agent that enables easy production of a zirconia sintered body having both high translucency and high strength despite containing a fluorescent agent. The present invention relates to a method for producing a zirconia particle- and fluorescent agent-containing powder, comprising: a mixing step of mixing a zirconia particle-containing slurry and a liquid-state fluorescent agent; and a drying step of drying the slurry containing the zirconia particles and the fluorescent agent. Preferably, the fluorescent agent comprises a metallic element, and the powder comprises the fluorescent agent in an amount of 0.001 to 1 mass % in terms of an oxide of the metallic element relative to a mass of zirconia. Preferably, the zirconia particles have an average primary particle diameter of 30 nm or less. Preferably, the zirconia particles comprises 2.0 to 9.0 mol % yttria.

The present invention provides a zirconia sintered body containing a fluorescent agent and having excellent translucency and excellent strength. The present invention also provides a zirconia shaped body and a zirconia calcined body from which the zirconia sintered body can be obtained. The present invention relates to a zirconia sintered body comprising a fluorescent agent, wherein the zirconia sintered body comprises 4.5 to 9.0 mol % yttria, and has a crystal grain size of 180 nm or less, and a three-point flexural strength of 500 MPa or more. The present invention relates to a zirconia shaped body comprising a fluorescent agent, wherein the zirconia shaped body comprises 4.5 to 9.0 mol % yttria, and has a three-point flexural strength of 500 MPa or more after being sintered at 1,100° C. for 2 hours under ordinary pressure, and a crystal grain size of 180 nm or less after being sintered at 1,100° C. for 2 hours under ordinary pressure. The present invention relates to a zirconia calcined body comprising a fluorescent agent, wherein the zirconia calcined body comprises 4.5 to 9.0 mol % yttria, and has a three-point flexural strength of 500 MPa or more after being sintered at 1,100° C. for 2 hours under ordinary pressure, and a crystal grain size of 180 nm or less after being sintered at 1,100° C. for 2 hours under ordinary pressure.

Provided are a dispersion for a silicon carbide sintered body having a small environmental load, high dispersibility, and excellent temporal stability, and a manufacturing method thereof.

The dispersion is a dispersion for a silicon carbide sintered body, containing: silicon carbide particles; boron nitride particles; a resin having a hydroxyl group; and water, wherein the dispersion has a pH at 25° C. of less than or equal to 7.0, and the silicon carbide particles and the boron nitride particles have charges of the same sign. The dispersion is manufactured by a manufacturing method of a dispersion for a silicon carbide sintered body, including a mixing step of mixing a water dispersion containing silicon carbide particles, a water dispersion containing boron nitride particles, and an aqueous solution containing a resin having a hydroxyl group.