Abstract: A sintered product presenting a mean chemical composition such that, in percentages by weight based on the oxides: Cr2O3: 72.0%-98.9% 2%<Al2O3?20% 0.1%?TiO2?6.0% ZrO2<4.0% SiO2?0.9%.

Abstract: Disclosed is a method of producing a plate brick, which comprises: adding an organic binder to a refractory raw material mixture containing aluminum and/or an aluminum alloy; kneading them; forming the kneaded mixture into a shaped body; and burning the shaped body in a nitrogen gas atmosphere at a temperature of 1000 to 1400° C., wherein: when a temperature of a furnace atmosphere is 300° C. or more, the atmosphere is set to a nitrogen gas atmosphere; and when the temperature of the furnace atmosphere is 1000° C. or more, an oxygen gas concentration in the atmosphere is maintained at 100 volume ppm or less, and a sum of a carbon monoxide gas concentration and a carbon dioxide gas concentration is maintained at 1.0 volume % or less.

Abstract: The disclosure relates to a refractory which is resistant to corrosion which degrades the refractory during titanium-ore beneficiation in a furnace, particularly a rotary hearth furnace. In particular, the disclosure relates to a layered refractory lining for a furnace, for use in a titanium ore beneficiation process wherein a titanium oxide-rich molten slag is formed, comprising: (a) a first layer comprising a major proportion of alumina and a minor proportion of zirconia; (b) a second layer comprising a resistant agent for the molten slag; wherein the second layer is between the slag and the first layer.

Abstract: To provide a high zirconia fused cast refractory which hardly has cracks, and has excellent durability and reusability, at the time of production of the refractory and during use for a glass melting furnace. A high zirconia fused cast refractory which has a chemical composition comprising from 85 to 95 mass % of ZrO2, at least 2.5 mass % of SiO2, at most 0.04 mass % of Na2O, at most 0.04 mass % of B2O3, and at most 0.04 mass % of P2O5, containing SrO as an essential component, and containing at least one of K2O and Cs2O, wherein contents of SrO, K2O and Cs2O satisfy the relations of the following formula (1) and (2) at the same time: 0.20?[0.638×CK2O+0.213×CCs2O+0.580×CSrO]/CSiO2?0.40??(1) 0.10?0.

Abstract: A fused and cast refractory product including, in mass percentages on the basis of the oxides and for a total of 100% of the oxides: ZrO2 + Hf2O: balance to 100%; SiO2: ?7.0% to 11.0%; Al2O3: 0.2% to 0.7%; Na2O + K2O: <0.10%; B2O3: 0.3% to 1.5%; CaO + SrO + MgO + ZnO + BaO: ?<0.4%; P2O5: <0.15%; Fe2O3 + TiO2: <0.55%; Other oxide species: ?<1.5%; the mass content of a dopant selected from Nb2O5, Ta2O5 and mixtures thereof being of less or equal to 1.0%, and the A/B ratio of the Al2O3/B2O3 mass contents being less than or equal to 2.0.

Abstract: The present invention provides a nanostructured composite material of ?-alumina-doped zirconia stabilised with cerium oxide and zirconia-doped ?-alumina, the process for obtaining it and the applications thereof, such as knee prostheses, hip prostheses, dental implants, mechanical components for pumps, alkaline batteries, ceramic components for stereotactic neurology, cutting tools, etc.

Abstract: A material mixture for producing a fireproof material, including spinel and zirconium oxide and a coarse-grained fraction with a weight fraction of greater than 50% and a fine-grained fraction, wherein the coarse-grained fraction includes coarse grains with dimensions larger than 20 ?m and the fine-grained fraction includes fine grains with dimensions smaller than 20 ?m.

Abstract: A solid solution-comprising ceramic article useful in semiconductor processing, which is resistant to erosion by halogen-containing plasmas. The solid solution-comprising ceramic article is formed from a combination of yttrium oxide, zirconium oxide, and aluminum oxide. In a first embodiment, the solid solution-comprising ceramic article is a solid, sintered body of the solid solution ceramic material. In a second embodiment, the solid solution-comprising article comprises a substrate underlying a solid solution-comprising coating.

Abstract: ESD safe ceramic component is provided which includes a sintered composition which is formed of a base material and a resistivity modifier. The base material includes a primary component and a secondary component, the primary component including Al2O3 and the secondary component including tetragonal-ZrO2.

Abstract: A refractory object can include at least approximately 10 wt % Al2O3 and at least approximately 1 wt % SiO2. In an embodiment, the refractory object can include an additive. In a particular embodiment, the additive can include TiO2, Y2O3, SrO, BaO, CaO, Ta2O5, Fe2O3, ZnO, or MgO. The refractory object can include at least approximately 3 wt % of the additive. In an additional embodiment, the refractory object can include no greater than approximately 8 wt % of the additive. In a further embodiment, the creep rate of the refractory object can be at least approximately 1×10?6 h?1. In another embodiment, the creep rate of the refractory object can be no greater than approximately 5×10?5 h?1. In an illustrative embodiment, the refractory object can include a glass overflow trough or a forming block.

Abstract: A solid oxide electrolyte including an oxygen ion conducting solid solution, wherein the solid solution is represented by Formula 1 below: Zr1-x-y-zMaxMbyMczO2-???Formula 1 wherein x is greater than 0 and less than about 0.3, y is greater than 0 and less than about 0.1, z is greater than 0 and less than about 0.1, ? is selected to make the solid solution ionically neutral, Ma, Mb, and Mc are each independently a metal selected from the group consisting of elements of Groups 3, Groups 5 through 13, and Group 14, and an ionic radius of each of Ma+3, Mb+3, and Mc+3 are different from each other.

Abstract: To provide a high zirconia fused cast refractory having high durability, which hardly has cracks during the heating, by temperature changes during use and during the cooling at the time of suspension of operation. A high zirconia fused cast refractory which has a chemical composition comprising from 86 to 96 mass % of ZrO2, from 2.5 to 8.5 mass % of SiO2, from 0.4 to 3 mass % of Al2O3, from 0.4 to 1.8 mass % of K2O, at most 0.04 mass % of B2O3, at most 0.04 mass % of P2O5 and at most 3.8 mass % of Cs2O and containing substantially no Na2O.

Abstract: To provide a high zirconia fused cast refractory which hardly has cracks, and has excellent durability and reusability, at the time of production of the refractory and during use for a glass melting furnace. A high zirconia fused cast refractory which has a chemical composition comprising from 85 to 95 mass % of ZrO2, at least 2.5 mass % of SiO2, at most 0.04 mass % of Na2O, at most 0.04 mass % of B2O3, and at most 0.04 mass % of P2O5, containing SrO as an essential component, and containing at least one of K2O and Cs2O, wherein contents of SrO, K2O and Cs2O satisfy the relations of the following formula (1) and (2) at the same time: 0.20?[0.638×CK2O+0.213×CCs2O+0.580×CSrO]/CSiO2?0.40 ??(1) 0.10?0.

Abstract: The present invention provides a fused refractory product having the following average chemical composition, as a % by weight based on the oxides and for a total of 100%; ZrO2: 30%-46%; SiO2: 10%-16%; Al2O3: complement to 100%; Y2O3?50/ZrO2 and Y2O3?5%; Na2O+K2O: 0.5%-4%; CaO: ?0.5%; and other species: ?1.5%. Application to a glass-melting furnace.

Abstract: The invention relates to a molten cast refractory product comprising, in weight percentages on the basis of the oxides and relative to a total of 100% of the oxides: ZrO2+Hf2O is the remainder making up 100%, 4.5%<SiO2<6.0%, 0.80%?Al2O3<1.10%, 0.3%<B2O3<1.5%, Ta2O5+Nb2O5<0.15%, Na2O+K2O<0.1%, K2O<0.04%, CaO+SrO+MgO+ZnO+BaO<0.4%, P2O5<0.05%, Fe2O3+TiO2<0.55%, and other oxide species<1.5%, the “A/B” ratio of the Al2O3/B2O3 contents by weight being between 0.75 and 1.6. The invention can be applied to glass melting furnaces.

Abstract: A sputtering target for forming a ZrO2—In2O3 based protective film for an optical storage medium, has a component composition made of ZraInbAcO100-a-b-c where “A” represents one, two, or more of Si, Cr, Al, Ce, Ti, and Sn, “a” represents an amount greater than 5 atomic percent and less than 23 atomic percent, “b” represents an amount greater than 12 atomic percent and less than 35 atomic percent, and “c” represents an amount greater than 0 and less than 30 atomic percent, wherein 90% or more of Zr that is included in the sputtering target for forming the protective film for the optical storage medium is in an oxidative product phase in which Zr and In are combined, and is dispersed in a base material of the target.

Abstract: The present invention relates to a molten, fluid refractory product comprising, in weight percentages on the basis of the oxides and for a total of 100% of the oxides: ZrO2+Hf2O: remainder to 100% 4.5%<SiO2<6.0% Al2O3<0.80% 0.3%<B2O3<1.0% Ta2O5+Nb2O5<0.15% Na2O+K2O<0.1% K2O<0.04% CaO+SrO+MgO+ZnO+BaO<0.4% P2O6<0.05% Fe2O3+TiO2<0.55% other oxide species, optionally including Y2O3: <1.5%, where Y2O3<0.3%, the “A/B” ratio of Al2O3/B2O3 content by weight being 0.5 to 2.0. The invention can be used in glass melting furnaces.

Abstract: A powder including, in percentages by weight: (a) 94% to 99% of particles of at least one refractory material, the main constituent(s) of which are alumina and/or zirconia and/or silica; (b) 1% to 6% of a hydraulic cement; (c) 0 to 0.03% of organic fibers; (d) optionally, 0.075% to 1% of a surfactant; and (e) optionally, a setting accelerator, where the fraction of particles having a size below 40 ?m being distributed, in percentages by weight relative to the weight of the powder, in the following manner: (1) fraction<0.5 ?m: ?4%, (2) fraction<2 ?m: ?5%, fraction<10 ?m: ?16%, and fraction<40 ?m: 29-45%, where the proportion of zirconia in the fraction of particles having a size smaller than 10 ?m, called “fines”, is between 35% and 75% by weight relative to the total weight of said fraction.

Abstract: Disclosed are ceramic articles comprising ceramic honeycomb bodies and an aqueous composition, for example in the form of a cold-set plug, as well as processes for preparing ceramic articles and processes for making an aqueous composition for use with ceramic articles, for example as a cold-set plug composition.

Abstract: This invention relates to thermally sprayed coatings of a high purity yttria or ytterbia stabilized zirconia powder, said high purity yttria or ytterbia stabilized zirconia powder comprising from about 0 to about 0.15 weight percent impurity oxides, from about 0 to about 2 weight percent hafnium oxide (hafnia), from about 6 to about 25 weight percent yttrium oxide (yttria) or from about 10 to about 36 weight percent ytterbium oxide (ytterbia), and the balance zirconium oxide (zirconia). Thermal barrier coatings for protecting a component such as blades, vanes and seal surfaces of gas turbine engines, made from the high purity yttria or ytterbia stabilized zirconia powders, have a density greater than 88% of the theoretical density with a plurality of vertical macrocracks homogeneously dispersed throughout the coating to improve its thermal fatigue resistance.

Abstract: A composite ceramic body with increased strength is disclosed. The composite ceramic body, composed of a matrix of alumina particles with a mean particle diameter ranging from 0.7 to 1.8 ?m and nano-zirconia particles with a particle diameter of 0.15 ?m or less, wherein the alumina particles and the nano-zirconia particles fall in a respective weight percentage ratio ranging from 80:20 to 95:5 with a relative density of 93% or more and wherein in a cross section, a total sum of surface areas of pores, having cross-sectional areas equal to or greater than surface areas of circles having the same diameters as a mean particle diameter of the alumina particles, falls in a value of 2.2% or less based on a whole of the cross-sectional areas.

Abstract: Method for producing a mold for use in casting reactive metals comprising preparing a slurry of a yttria-based refractory composition and a binder, and using said slurry as a mold facecoat by applying said slurry onto a surface of a mold pattern, wherein said yttria-based refractory composition is obtainable by (a) mixing particles of a yttria-based ceramic material and a fluorine containing dopant, and (b) heating the resulting mixture to effect fluorine-doping of said yttria-based ceramic material.

Abstract: The present invention provides a plate brick having a low amount of generation of smoke and a gas with a pungent odor during use, and exhibiting high durability. A plate brick of the present invention is obtained by: adding an organic binder to a refractory raw material mixture containing 0.5 to 20 mass % of aluminum and/or aluminum alloy; kneading the mixture with the organic binder; forming the kneaded mixture into a shaped body; and subjecting the shaped body to a heat treatment at a temperature of 400 to 1000° C., wherein the plate brick is obtained without being impregnated with a carbon-containing liquid material comprising tar or pitch, after the heat treatment. The plate brick has a compressive strength of 180 MPa or more, and a weight-increasing rate of 1% or less as measured in a hydration test using an autoclave.

Abstract: The invention relates to a powder comprising more than 70% of refractory particles, in weight percent relative to the weight of the powder, a particle of said powder being classed in the fraction called “matrix” or in the fraction called “aggregate”, according to whether it is smaller than, or equal to 100 ?m, or larger than 100 ?m, respectively, said powder comprising, in weight percent relative to the weight of the powder: between 0.1% and 18% of particles of a heat-activatable binder, called “heat-activatable binder particles”; and more than 40% of refractory particles, called “ATZ particles”, having the following chemical composition, in weight percentages on the basis of the oxides of said ATZ particles: 10%?Al2O3?55%; 35%?TiO2?80%; 1%?MgO+Cr2O3?10%; 8%?ZrO2?20%; SiO2?8%.

Abstract: A fused and cast refractory product containing, in weight percentages on the basis of the oxides and for a total of 100%: ZrO2: remainder up to 100% Hf2O: <5% SiO2: 2% to 10% 0.9%<Y2O3+CeO2+CaO+MgO?4.0% B2O3: ?4.5% B2O3: ?0.09×(Y2O3+?(CeO2+CaO+MgO))×SiO2 Al2O3: 0.3% to 2.0% Na2O+K2O: ?0.5% P2O5: <0.05% Fe2O3 TiO2: <0.55% other species: <1.0%, as long as the Y2O3 content is no lower than 0.5% and the CeO2 +CaO+MgO content is no lower than 2%.

Abstract: Fused and cast refractory product including on oxides basis in percent by weight and for a total of 100%: ZrO2+HfO2 complement to 100%; 3.5% to 6.0% SiO2; 0.7% to 1.5% Al2O3; 0.10% to 0.43% Na2O+K2O; 0.05% to 0.80% B2O3; less than 0.4% CaO+SrO+MgO+ZnO; less than 0.05% P2O5; less than 0.55% Fe2O3+TiO2; less than 1.5% other species. The ratio of percentages by weight of Al2O3/(Na2O+K2O) being greater than or equal to 3.5 and the ratio of percentages by weight of B2O3/(Na2O+K2O) being between 0.3 and 2.5.

Abstract: Porous structure comprising an oxide ceramic material comprising, on the basis of the corresponding simple oxides: Al2O3, TiO2, at least one oxide of an element M2 chosen from the group formed by Fe2O3, Cr2O3, MnO2, La2O3, Y2O3 and Ga2O3, at least one oxide of an element M3 chosen from the group formed by ZrO2, Ce2O3 and HfO2, optionally at least one oxide of an element M1 chosen from MgO and CoO, and optionally SiO2, said material being obtained by the reactive sintering of the corresponding simple oxides or of their precursors or by heat treatment of the sintered particles satisfying said composition.

Abstract: The invention provides a novel fused cast refractory product with a high zirconia content having improved electrical resistivity. Said refractory product comprises, as a percentage by weight based on the oxides and for a total of more than 98.5%: ZrO2 + Hf2O: >85%; SiO2: >10% to 12%; Al2O3: 0.1% to 2.4%; B2O3: <1.5%; and a dopant selected from the group formed by V2O5, CrO3, Nb2O5, MoO3, Ta2O5, WO3, and mixtures thereof, in a weighted quantity as expressed below: 2.43V2O5+4.42CrO3+1.66Nb2O5+3.07MoO3+Ta2O5+1.91WO3?0.2%.

Abstract: In one aspect, the invention includes a heat stable, formed ceramic component that includes a multimodal grain distribution including (i) at least 50 wt % of coarse grains including stabilized zirconia, the coarse grains comprising a D50 grain size in the range of from 5 to 800 ?m, based upon the total weight of the component; and (ii) at least 1 wt % of fine grains comprising a D50 average grain size not greater than one-fourth the D50 grain size of the coarse grain, dispersed within the coarse grains, based upon the total weight of the component; wherein after sintering, the component has porosity at ambient temperature in the range of from 5 to 45 vol. %, based on the formed volume of the component.

Abstract: The invention provides a fused cast refractory product with a high zirconia content comprising, as. a percentage by weight based on the oxides: ZrO2+Hf2O: >85%; SiO2: 6% to 12%; Al2O3: 0.4% to 1%; Y2O3: 0.2%; a dopant selected from the group formed by Nb2O5, Ta2O5, and mixtures thereof, in a quantity such that the molar ratio ZrO2/(Nb2O5+Ta2O3) is in the range 200 to 350.

Abstract: A highly zirconia-based refractory suitable for an electric melting furnace, which has a high electrical resistivity and does not exhibit a chipping off phenomenon and which is scarcely susceptible to extraction of components even when in contact with molten low alkali glass and, hence, is less susceptible to cracking during operation. The highly zirconia-based refractory that includes, as chemical components by mass %, from 85 to 95% of ZrO2 in terms of inner percentage, from 3.0 to 10% of SiO2 in terms of inner percentage, from 0.85 to 3.0% of Al2O3 in terms of inner percentage, substantially no Na2O, from 0.01 to 0.5% of K2O in terms of outer percentage, from 1.5 to 3.0% of SrO in terms of inner percentage, and from 0.1 to 2.0% of Nb2O5 and/or Ta2O5 as a value obtained by [(Nb2O5 content)+(Ta2O5 content/1.66)], in terms of inner percentage.

Abstract: Methods of making and compositions of dense sintered ceramic nano- and micro-composite materials that are highly stable in a variety of conditions and exhibit superior toughness and strength. Liquid feed flame spray pyrolysis techniques form a plurality of nanoparticles (e.g., powder), each having a core region including a first metal oxide composition comprising Ce and/or Zr or other metals and a shell region including a second metal oxide composition comprising Al or other metals. In certain aspects, the core region comprises a partially stabilized tetragonal ZrO2 and the shell region comprises an ?-Al2O3 phase. The average actual density of the ceramic after sintering is greater than 50% and up to or exceeding 90% of a theoretical density of the ceramic.

Abstract: The present invention provides biocidal ceramic compositions incorporating a bioactive ionic species that is chemically bound in a substantially single-phase, crystalline, [NZP]-type structure, methods for producing the crystalline structures, and articles of manufacture incorporating the crystalline structures, and uses of the articles of manufacture. Bioactive ionic species can be, but are not limited to, Ag, Cu, Ni, Zn, Mn, Sn, Co, H, and combinations thereof.

Abstract: This invention relates to thermal spray composite coatings on a metal or non-metal substrate. The thermal spray composite coatings comprise a ceramic composite coating having at least two ceramic material phases randomly and uniformly dispersed and/or spatially oriented throughout the ceramic composite coating. At least a first ceramic material phase is present in an amount sufficient to provide corrosion resistance to the ceramic composite coating, and at least a second ceramic material phase is present in an amount sufficient to provide plasma erosion resistance to the ceramic composite coating. This invention also relates to methods of protecting metal and non-metal substrates by applying the thermal spray coatings. The composite coatings provide erosion and corrosion resistance at processing temperatures higher than conventional processing temperatures used in the semiconductor etch industry, e.g., greater than 100° C.

Abstract: A green part, a region of a refractory furnace or a hollow piece for producing a sintered refractory has the following mean mineral chemical composition in weight percent based of mineral oxides: 40%?Al2O3?94%, 0%?ZrO2?41%, 2%?SiO2?22%, 1%<Y2O3+V2O5+TiO2+Sb2O3+Yb2O3+Na2O. The sintered refractory products obtained from this green part give rise to a reduced bubbling effect.

Abstract: This invention relates to high purity yttria or ytterbia stabilized zirconia powders comprising from about 0 to about 0.15 weight percent impurity oxides, from about 0 to about 2 weight percent hafnium oxide (hafnia), from about 6 to about 25 weight percent yttrium oxide (yttria) or from about 10 to about 36 weight percent ytterbium oxide (ytterbia), and the balance zirconium oxide (zirconia). Thermal barrier coatings for protecting a component such as blades, vanes and seal surfaces of gas turbine engines, made from the high purity yttria or ytterbia stabilized zirconia powders, have a density greater than 88% of the theoretical density with a plurality of vertical macrocracks homogeneously dispersed throughout the coating to improve its thermal fatigue resistance.

Abstract: The invention relates to a molten ceramic particle, characterized in that it has the following chemical composition in wt % based on oxides and for a total of 100%: 55%<ZrO2+HfO2<70%; 20%<SiO2<30%; 6.5%<MgO<9.5%; Al2O3 in an amount such that the mass ratio MgO/Al2O3 is comprised between 2.4 and 6.6; and less than 0.6% of other oxides.

Abstract: Fused particles containing, by weight percent: more than 15% but less than 55% of Al2O3; more than 20% but less than 45% of TiO2; more than 3% but less than 30% of SiO2; less than 20%, in total, of at least one oxide selected from the group consisting of ZrO2, Ce2O3, and HfO2; less than 1% of MgO; and more than 1% but less than 15%, in total, of at least one selected from the group consisting of CaO, Na2O, K2O, SrO, B2O3, and BaO. Also, a ceramic product or material obtained by sintering the fused particles.

Abstract: A sintered product presenting a mean chemical composition such that, in percentages by weight based on the oxides: Cr2O3: 72.0%-98.9% 2%<Al2O3?20% 0.1%?TiO2?6.0% ZrO2<4.0% SiO2?0.9%.

Abstract: Provided is a zirconia-mullite refractory raw material which is less likely to undergo alternation and microstructural degradation under high-temperature conditions, and low in thermal expansion rate, so as to have thermal shock resistance and corrosion resistance. The zirconia-mullite refractory raw material comprises crystalline zirconia and mullite as primary components, with the remainder being corundum and/or a matrix glass, wherein the crystalline zirconia includes a eutectic zirconia crystal having a grain size of 1.0 ?m or less, and has a maximum grain size of 30 ?m or less, and the matrix glass is contained in an amount of 5 mass % or less. The zirconia-mullite refractory raw material has a chemical composition comprising 30 to 55 mass % of ZrO2, 30 to 55 mass % of Al2O3 and 10 to 25 mass % of SiO2, wherein each of the chemical components falls within a primary phase region of ZrO2 in an Al2O3—ZrO2—SiO2 system phase diagram.

Abstract: The invention is directed to an apparatus substantially eliminating destructive low-temperature, humidity-enhanced phase transformation of yttria-stabilized zirconia in general, as well as eliminating low-temperature degradation of yttria-stabilized tetragonal zirconia polycrystalline ceramic (Y-TZP). The martensitic-type phase transformation from tetragonal to monoclinic is accompanied by severe strength degradation in a moist environment at low-temperature, specifically at room temperature as well as at body temperature. This class of materials has been chosen as the packaging material for small implantable neural-muscular sensors and stimulators because of the high fracture toughness and high mechanical strength. This destructive phase transformation has been substantially eliminated, thus ensuring the safety of long-term implants, by subjecting the sintered components to post-machining hot isostatic pressing, such that the average grain size is less than about 0.5 microns.

Abstract: The disclosure relates to a refractory which is resistant to corrosion which degrades the refractory during titanium-ore beneficiation in a furnace, particularly a rotary hearth furnace. In particular, the disclosure relates to a layered refractory lining for a furnace, for use in a titanium ore beneficiation process wherein a titanium oxide-rich molten slag is formed, comprising: (a) a first layer comprising a major proportion of alumina and a minor proportion of zirconia; (b) a second layer comprising a resistant agent for the molten slag; wherein the second layer is between the slag and the first layer.

Abstract: Slip for use in a hot-melt inkjet printing process which contains (A) ceramic particles, (B) wax and (C) at least one radically polymerizable monomer, and use of the slip to prepare dental restorations. Furthermore, a process for the preparation of a green compact is described, in which the slip is molded in layers to the geometrical shape of the green compact and subjected to a radical polymerization in order to obtain a cured green compact.

Abstract: The present invention provides a fused cast refractory block comprising a mean zirconia (ZrO2+HfO2) content of more than 85% as a percentage by weight based on the oxides, and with a standard deviation ? of the local zirconia content divided by the volume of the block of less than 7.5.

Abstract: A fused and cast refractory product including, in mass percentages on the basis of the oxides and for a total of 100% of the oxides: ZrO2 + Hf2O: balance to 100%; SiO2: ?7.0% to 11.0%; Al2O3: 0.2% to 0.7%; Na2O + K2O: <0.10%; B2O3: 0.3% to 1.5%; CaO + SrO + MgO + ZnO + BaO: ?<0.4%; P2O5: <0.15%; Fe2O3 + TiO2: <0.55%; Other oxide species: ?<1.5%; the mass content of a dopant selected from Nb2O5, Ta2O5 and mixtures thereof being of less or equal to 1.0%, and the A/B ratio of the Al2O3/B2O3 mass contents being less than or equal to 2.0.

Abstract: A ZrO2—Al2O3 composite ceramic material having excellent wear resistance, hardness, strength and toughness is provided. This ceramic material comprises a ZrO2 phase composed of 90 vol % or more of tetragonal ZrO2, and containing 10 to 12 mol % of CeO2 as a stabilizer, and an Al2O3 phase. An amount of the Al2O3 phase in the ceramic material is in a range of 20 to 70 vol %, and preferably 40 to 70 vol %. In the composite ceramic material, Al2O3 grains each having a fine ZrO2 grain therein are dispersed. Some of the Al2O3 grains each having the fine ZrO2 grain therein are trapped within ZrO2 grains to form composite grains. A ratio of the number of the Al2O3 grains each having the fine ZrO2 grain therein relative to the number of the entire Al2O3 grains dispersed in the composite ceramic material is 10% or more, and preferably 50% or more.

Abstract: Method for producing a mold for use in casting reactive metals comprising preparing a slurry of a yttria-based refractory composition and a binder, and using said slurry as a mold facecoat by applying said slurry onto a surface of a mold pattern, wherein said yttria-based refractory composition is obtainable by (a) mixing particles of a yttria-based ceramic material and a fluorine containing dopant, and (b) heating the resulting mixture to effect fluorine-doping of said yttria-based ceramic material.

Abstract: The present invention provides a fused refractory product having the following average chemical composition, as a % by weight based on the oxides and for a total of 100%; ZrO2: 30%-46%; SiO2: 10%-16%; Al2O3: complement to 100%; Y2O3?50/ZrO2 and Y2O3?5%; Na2O+K2O: 0.5%-4%; CaO: ?0.5%; and other species: ?1.5%. Application to a glass-melting furnace.

Abstract: To provide a process for producing high-purity highly oxidized refractory particles easily with good productivity by treating a spent refractory containing ZrO2 and Al2O3 to reduce components other than ZrO2 and Al2O3 to levels unproblematic for practical use as raw material for electrofused refractories and to increase the content of the ZrO2 and/or Al2O3 component. A process for producing refractory particles, which comprises introducing to and melting in a melting furnace both a spent refractory which contains, by mass % as chemical components, from 75 to 97% of ZrO2 and/or Al2O3, from 2 to 25% of SiO2, from 0.4 to 7% in total of Na2O, K2O and Li2O(Na2O+K2O+Li2O), at most 2% of CaO and at most 2% of MgO, and carbon particles in an amount of from 1 to 8% by outer mass percentage based on the spent refractory, and after the melting, tapping the melt while blowing compressed air against the melt to form refractory particles having the content of ZrO2 and/or Al2O3 increased.

Abstract: This invention relates to ceramic powders comprising a zirconia-based component, e.g., yttria-stabilized zirconia, and an (alumina+silica)-based component, e.g., mullite. The ceramic powders are useful for forming thermal shock resistant coatings having the same composition, through deposition by thermal spray devices. This invention also relates to thermal barrier coating systems suitable for protecting components exposed to high temperature environments, such as the thermal environment of a gas turbine engine. This invention further relates to forming free-standing solid ceramic articles.