A method for manufacturing a zirconia sintered body includes molding a powder composition that has a yttria content of more than 3% by mole and 5.2% by mole or less and that contains a first zirconia powder having a yttria content of 2% by mole or more and 4% by mole or less and a second zirconia powder having a yttria content of more than 4% by mole and 6% by mole or less to obtain a green body, and sintering the green body to obtain a sintered body.

A zirconia powder is provided comprising a yttria source and zirconia, wherein a content of the yttria source is 4.5 mol % or more and 6.5 mol % or less and the remainder is zirconia, a ratio of a total of tetragonal and cubic crystals to an entire crystal phase of zirconia is 90% or less, a BET specific surface area is 7.5 m.sup.2/g or more and 15 m.sup.2/g or less, and an average crystallite size is 325 Å or greater. The powders are useful in producing sintered bodies having the mechanical strength and the translucency desired for use in dental prosthetic materials, and precursors thereof.

A composition comprises a zirconia powder, in which 55% or more thereof is monoclinic, and a stabilizer capable of suppressing phase transition of zirconia. An average particle diameter of zirconia particles and particles of the stabilizer is 0.06 μm to 0.17 μm. At least a portion of the stabilizer does not form a solid solution with zirconia.

A composition comprises a zirconia powder, in which 55% or more thereof is monoclinic, and a stabilizer capable of suppressing phase transition of zirconia. An average particle diameter of zirconia particles and particles of the stabilizer is 0.06 μm to 0.17 μm. At least a portion of the stabilizer does not form a solid solution with zirconia.

A refractory lining in a combustion chamber operating in a reducing atmosphere. The lining includes at least one or more Zirconia (Zr)-based refractory lining members comprising one or more Zr-based parts. The Zr-based parts comprise at least 90 wt. %, preferably at least 95 wt. %, of monoclinic ZrO.sub.2 and/or partially stabilized ZrO.sub.2 and/or fully stabilized ZrO.sub.2, wherein the total content of tetragonal and cubic ZrO.sub.2 amounts to at least 20 wt. %, preferably more than 35 wt. %, as well as Zr based refractory lining members and methods for manufacturing the Zr based refractory lining members.

A zirconia powder is provided comprising a yttria source and zirconia, wherein a content of the yttria source is 4.5 mol % or more and 6.5 mol % or less and the remainder is zirconia, a ratio of a total of tetragonal and cubic crystals to an entire crystal phase of zirconia is 90% or less, a BET specific surface area is 7.5 m.sup.2/g or more and 15 m.sup.2/g or less, and an average crystallite size is 325 Å or greater. The powders are useful in producing sintered bodies having the mechanical strength and the translucency desired for use in dental prosthetic materials, and precursors thereof.

A composite ceramic including: a lithium garnet major phase; and a grain growth inhibitor minor phase, as defined herein. Also disclosed is a method of making composite ceramic, pellets and tapes thereof, a solid electrolyte, and an electrochemical device including the solid electrolyte, as defined herein.

An object is to provide metal element-having ceramic continuous fibers suitable for use in the production of highly heat-resistant CMCs, and a CMC made therewith. The ceramic continuous fibers comprise ceramic continuous fibers and at least one metal element therein, with the concentration by mass of the metal element being 10 ppm or more and 1000 ppm or less.

The present invention relates to a dental zirconia mill blank comprising a porous zirconia material, the porous zirconia material comprising Zr oxide, Y oxide, optionally Al oxide, Bi oxide, Tb oxide, Er oxide, Cr oxide, the porous zirconia material not comprising Fe oxide calculated as Fe.sub.2O.sub.3 of more than 0.01 wt. %, Mn oxide calculated as MnO.sub.2 of more than 0.005 wt. %, Co oxide calculated as Co.sub.2O.sub.3 of more than 0.005 wt. %, wt. % with respect to the weight of the porous zirconia material. The invention also relates to a process of producing such a dental zirconia mill blank and a dental restoration which can be machined from the dental zirconia mill blank. Further, the invention relates to a kit of parts comprising such a dental zirconia mill blank and a dental cement.

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.