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 paramagnetic garnet-type transparent ceramic is a sintered body of complex oxide represented by the following formula (1), comprising SiO.sub.2 as a sintering aid in an amount of more than 0% by weight to 0.1% by weight or less, and has a linear transmittance of 83.5% or more at the wavelength of 1,064 nm for an optical path length of 25 mm:
(Tb.sub.1-x-yY.sub.xSc.sub.y).sub.3(Al.sub.1-zSc.sub.z).sub.5O.sub.12  (1)
wherein 0.05≤x<0.45, 0<y<0.1, 0.5<1−x−y<0.95, and 0.004<z<0.2.

Process for treating a porous dental zirconia block with a coloring solution, the process comprising the steps of providing a porous dental zirconia block having two opposing surfaces, surface U and surface L, treating the upper surface U of the porous dental zirconia block with a coloring solution A.sub.1, wherein the coloring solution is provided with a volume VA.sub.1, turning the porous dental zirconia block around, treating the lower surface L with a coloring solution A.sub.2 which is provided with a volume VA.sub.2. wherein the coloring solutions A.sub.1 and A.sub.2 comprise a solvent and coloring ions, wherein the volume of at least one of the coloring solutions A.sub.1 or A.sub.2 is applied in portions, wherein the following condition is met: Vo=ΣV.sub.AX, with x≥2, with Vo being the overall amount of coloring solution used to infiltrate the porous dental zirconia block.

A YAG ceramic bonded body in which a YAG ceramic and a YAG ceramic or optical glass are bonded, wherein the YAG ceramic bonded body comprises glass as a bonding layer, and has a rate of change of transmittance that is within 7%. An object of this invention is to provide a bonded body in which a YAG ceramic and a YAG ceramic are bonded, or a bonded body in which a YAG ceramic and optical glass are bonded, and which is capable of suppressing the reflection of light at the bonded interface, as well as the production method thereof.

A powder intended for the manufacture of a sintered dental article, The powder has a chemical analysis such that, as weight percentages based on the oxides: Al.sub.2O.sub.3: 0.2%, oxides other than ZrO.sub.2, HfO.sub.2, Yb.sub.2O.sub.3, Y.sub.2O.sub.3 and Al.sub.2O.sub.3: <0.5%, and ZrO.sub.2+HfO.sub.2+Yb.sub.2O.sub.3+Y.sub.2O.sub.3: balance to 100%, with HfO.sub.2<2%. The contents of Yb.sub.2O.sub.3 and Y.sub.2O.sub.3, as molar percentages based on the sum of ZrO.sub.2, HfO.sub.2, Yb.sub.2O.sub.3 and Y.sub.2O.sub.3, being such that Yb.sub.2O.sub.3≥1%, 0.5%≤Y.sub.2O.sub.3<2%, and Yb.sub.2O.sub.3+Y.sub.2O.sub.3≤5.5%. The powder has a specific surface area of greater than or equal to 5 m.sup.2/g and less than or equal to 16 m.sup.2/g. The powder has a median size of greater than or equal to 0.1 μm and less than or equal to 0.7 μm.

The present disclosure provides a method of making a ceramic article. The method includes (a) obtaining a photopolymerizable slurry or sol including a plurality of ceramic particles distributed in the photopolymerizable slurry or sol and (b) selectively polymerizing the photopolymerizable slurry or sol using actinic radiation and continuous movement of a build substrate through the photopolymerizable slurry or sol to form a gelled article. The method also includes (c) extracting solvent from the gelled article to form an aerogel article or a xerogel article; (d) heat treating the aerogel article or the xerogel article to form a porous ceramic article; and (e) sintering the porous ceramic article to form a sintered ceramic article. The sintered ceramic article exhibits a particular density. Further, additive manufactured ceramic articles are provided that exhibit a particular density, opacity, or both. Preferably, all cross-sectional portions of an interior of the ceramic article having selected dimensions are free of a frequency analysis signal maxima larger than a background signal.

A zirconia powder containing a stabilizer, and having a specific surface area of 20 m.sup.2/g or more and 60 m.sup.2/g or less and a particle diameter D.sub.50 of 0.1 μm or more and 0.7 μm or less, in which in a range of 10 nm or more and 200 nm or less in a pore distribution based on a mercury intrusion method, a peak top diameter in a pore volume distribution is 20 nm or more and 85 nm or less, a pore volume is 0.2 ml/g or more and less than 0.5 ml/g, and a pore distribution width is 40 nm or more and 105 nm or less.

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.

Invention relates to the production method of transparent polycrystalline silicon nitride ceramics which are obtained by sintering raw materials in powder form with powder metallurgy in the field of advanced technical ceramics and are used in the aviation and defense industry. More specifically, the present invention relates to a transparent polycrystalline silicon nitride ceramic material production method which allows obtaining transparent polycrystalline silicon nitride ceramic material at lower temperature and pressure values compared to the prior art in order to reduce production costs, facilitate the production process and reduce quantity/number of material and devices used, for this, unlike conventional sintering technique, spark plasma sintering technique in which heat is produced under high electrical current is used.

An iterative approach to dynamic covalent polymerizations of elemental sulfur with functional comonomers to prepare sulfur prepolymers that can further react with other conventional, commercially available comonomers to prepare a wider class of functional sulfur polymers. This iterative method improves handling, miscibility and solubility of the elemental sulfur, and further enables tuning of the sulfur polymer composition. The sulfur polymers may be a thermoplastic or a thermoset for use in elastomers, resins, lubricants, coatings, antioxidants, cathode materials for electrochemical cells, and polymeric articles such as polymeric films and free-standing substrates.