VERFAHREN ZUR HERSTELLUNG VON HYDRATIERTEM ZIRKONIUMOXID AUS GRANULIERTEM KRISTALLINEM ZIRKONIUMOXID.

CLEANING STRUCTURE WITH INTEGRATED ELECTRO-CHEMICAL ONE CATALYSIS SYSTEM

ACTIVE DERIVATIVE OF ZIRCONIUM AND ITS PRODUCTION.

THERMALLY STABLE ONES OF ISOLATION CONSTRUCTION UNITS FROM FIREPROOF KERAMIKFASERN

PROCESS FOR THE MANUFACTURE OF ZIRCONIUM OXIDE HYDRATE FROM GRANULAR CRYSTALLIZED ZIRCONIUM OXIDE

FUSED CERAMIC BEADS

METHOD FOR PREPARING A POROUS STRUCTURE USING SILICA-BASED PORE-FORMING AGENTS

The invention relates to a process for manufacturing a porous silicon carbide structure of the honeycomb type, said process being characterized in that it comprises the following steps: forming of a paste from a mixture of silicon carbide grains, the diameter d50 of which is between 5 mum and 300 mum, of an organic binder and of an inorganic pore former, in the form of particles based on silica, the overall porosity of said particles being greater than 70%; forming of a honeycomb-shaped green plastic monolith; drying of said monolith; and firing of the monolith at a temperature greater than 2100° C. The structure obtained by the process may be used as catalytic support in an exhaust line of a diesel or petrol engine or as particulate filter in an exhaust line of a diesel engine.

Thermisch stabile Isolierbauteile aus feuerfesten Keramikfasern

BALLS FROM MELTED CERAMIC MATERIAL

DUENNE CERAMIC PARTS, RECEIVING BY MELTS AND POURING OF A COMPOSITION FROM THE SYSTEM AL2O3-ZRO2-SIO2-K2O.

THIN CERAMIC ARTICLES OBTAINED FUSING AND CASTING IN A MOLD A COMPOSITION OF THE SYSTEM AL2O-ZRO2-SIO2-K2O WHICH HAVE GOOD MECHANICAL STRENGTH AND ABRASION RESISTANCE PROPERTIES

PURIFICATION STRUCTURE INCORPORATING AN ELECTROCHEMICAL CATALYSIS SYSTEM

FUSED CERAMIC BEADS

The invention relates to fused ceramic beads, which have the following chemical composition in % by weight on the basis of the oxides: 40 to 95 % of ZrO2 and HfO2; at least one of Y2O3 and CeO2, with the provisos that Y2O3, when present, represents 0.1 to 10 % and CeO2, when present, represents 1 to 15 %, the total of Y2O3 and CeO2 representing 0.1 to 25 %; a quantity of SiO2 representing 10 to 45 % of the composition when CeO2 is absent from the composition and 0.5 to 45 % when CeO2 is present in the composition. Application to grinding and to dispersion in wet medium.

USING METHOD OF PREPARATION Of a POROUS STRUCTURE OF AGENTS POROGENES CONTAINING SILICA

L'invention se rapporte à un procédé de fabrication d'une structure poreuse en carbure de silicium du type en nid d'abeilles, ledit procédé étant caractérisée en ce qu'il comprend des étapes de formation d'une pâte à partir d'un mélange de grains de carbure de silicium dont le diamètre d5o est compris entre 5 µm et 300 µm, d'un liant organique et d'un agent porogène inorganique, sous forme de particules à base de silice et dont la porosité globale est supérieure à 70%, de mise en forme d'un monolithe plastique brut en forme de nid d'abeille, de séchage dudit monolithe et de cuisson du monolithe jusqu'à une température supérieure à 2100°C. La structure obtenue par le procédé peut être utilisée comme support catalytique dans une ligne d'échappement d'un moteur diesel ou essence ou comme filtre à particules dans une ligne d'échappement d'un moteur diesel.

Thermisch stabile Isolierbauteile aus feuerfesten Keramikfasern.

PROPPING AGENT BASED UPON ZIRCONIUM OXIDE AND SILICA FOR DEEP GEOLOGICAL FRACTURES

PROCEDURE FOR THE PRODUCTION A PORÍSEN OF A STRUCTURE USING PORE-FORMING MEANS ON SILICON BASIS

Fused ceramic beads

PRODUCTION OF ZIRCONIUM OXIDE HYDRATE FROM GRANULAR CRYSTALLIZED ZIRCONIUM OXIDE

PURPOSE: To save stages and to obtain ZrO2 hydrate at a low cost by bringing a granular crystallized Zr oxide into reaction with solid NaOH, hydrolyzing the reaction product and treating the product with an ammonium salt of a strong acid, then neutralizing the product with a strong acid. CONSTITUTION: The granular crystallized zirconium, for example, thermal zirconia, is mixed with the solid NaOH in such a manner that at least the stoichiometric ratio, more preferably weight ratio NaOH/ZrO2, attains 0.7 to 0.85. The mixture is brought into reaction at 550 to 1400°C, more adequately 950°C, by which Na2ZrO≥34X is obtd. at conversion efficiency of at least 95%. This reaction product is hydrolyzed for 10 to 75 minutes at 30 to 90°C, more adequately 60°C by using water of 3.5 to 11 times in molar ratio. The greater part of the NaOH is removed by filtration, etc., from a suspension of the formed ZrO2.nH2O and is washed with an aq. NH4Cl soln. The remaining NaOH is removed, washed and dehydrated ...

REACTIVE ZIRCONIUM OXIDE AND ITS PREPARATION

ABSTRACT The invention relates to the chemistry of zirconium. It relates particularly to a reactive zirconium oxide in the form of fine particles whose median diameter does not exceed 10 µm, which has a structure chosen from the amorphous structure and the structure crystallized in the tetragonal form, the size of the elementary coherence regions in the latter case being between 10 and 30 nm, and which has a B.E.T. surface area of at least 30 m2/g, and to a process for its preparation. Use in the field of ceramic materials.

POROUS CERAMIC PRODUCTS OF TITANIUM SUB-OXIDES

The invention relates to a method for manufacturing porous products made up essentially of titanium sub-oxide(s) with generic formulation TiOx, the value of x being from 1.6 to 1.9, said method comprising the following steps: a) mixing raw materials comprising at least one source of titanium dioxide, a reducing agent comprising carbon; b) shaping the product; c) optionally, in particular when organic products are used during step a), thermal treatment in air or oxidising atmosphere; d) sintering, for example at a temperature higher than 1150°C but not exceeding 1430°C, under a neutral or reducing atmosphere, in which the source of titanium dioxide is made up of at least 55 wt% of anatase. The invention also relates to a product that can be obtained by such a method.

Molten ceramic matter balls

L'invention concerne des billes en matière céramique formées par fusion d'une charge de matières premières, conversion de la matière fondue obtenue en billes et solidification de celles-ci, qui présentent la composition chimique suivant en % en poids sur la base des oxydes: 40 à 95% de ZrO2 et HfO2 ; au moins l'un de Y2 O3 et CeO2 avec les conditions que Y2 O3 représente 0,1 à 10% et CeO2 représente 0,1 à 20%, le total de Y2 O3 et CeO2 représentant 0,1 à 30%; une quantité de SiO2 représentant 10 à 45% de la composition lorsque CeO2 est absent de la composition et 0,5 à 45% lorsque CeO2 est présent dans la composition. Application au broyage et à la dispersion en milieu humide.

Kugeln aus geschmolzenen keramischen Werkstoff.

PROPPING AGENT BASED ON ZIRCONIA AND SILICA FOR DEEP GEOLOGICAL FRACTURES

PROPPING AGENT BASED ON ZIRCONIA AND SILICA FOR DEEP GEOLOGICAL FRACTURES. Daniel URFFER SOCIETE EUROPEENNE DES PRODUITS REFRACTAIRES The invention relates to the field of petroleum extraction. It relates, more precisely, to a granular propping agent of high mechanical resistance, having a density less than 3250 kg/m3, which consists of balls formed by melting, granulating and solidifying an initial composition comprising by weight, on the basis of the oxides, 46 to 50 parts of ZrO2, 54 to 50 parts of SiO2, the total of ZrO2 + SiO2 amounting to 100 parts, 0 to 19 parts of Al2O3 and 0 to 13.5 parts of at least one oxide selected from the group formed by MgO, CaO FeO and TiO2.

PURIFICATION STRUCTURE INCORPORATING AN ELECTROCHEMICAL CATALYSIS SYSTEM

The invention relates to a structure for the purification of a contaminated gas, for example the exhaust gas from a diesel or petrol engine, the structure incorporating an electrochemical system for treating said gas, composed of an NOx reduction catalyst A, a hydrocarbon oxidation catalyst B, an electron-conducting compound C and an ion-conducting compound D, said structure being characterized in that it is made of or covered with at least one porous, inorganic, electron-conducting and/or ion-conducting material in such a way that the catalysts A and B are disposed in the porosity of the inorganic material and that the ion-conducting, electron-conducting or ion-conducting and electron-conducting inorganic material makes up, respectively, the element C, the element D, or the sum of the elements C and D of said electrochemical system.

REAKTIVES ZIRKONIUMOXID UND SEINE HERSTELLUNG.

Method for preparing a porous structure using silica-based pore-forming agents

THIN CERAMIC ARTICLES OBTAINED FUSING AND CASTING IN A MOLD A COMPOSITION OF THE SYSTEM AL 0-ZRO -SIO -K O WHICH HAVE GOOD MECHANICAL STRENGTH AND ABRASION RESISTANCE PROPERTIES

The invention relates to ceramic articles. It relates to an article made of ceramic material shaped by fusing and casting in a mold a com-position based on alumina, zirconia, silica and an alkali metal oxide, the said article having, in at least one of its parts, a thickness lower than or equal to 30 mm and being intended for an application where mechanical strength and/or abrasion resistance are of primary importance, characterized in that it has the following chemical composition, in % by weight based on the oxides: Al2O3 : 40 - 75 ZrO2 : 20 - 45 SiO2 : 5 - 20 Na2O : 0 - 2.7 K2O : 0.15 - 4.25 Fe2O3+TiO2+CaO+MgO : 0 - 2, with the conditions that (i) each of Fe2O3, TiO2, CaO and MgO does not exceed 0.7% by weight, and (ii) that the weight ratio Na2O + K2O/1.52 SiO2 is between 0.07 and 0.14 inclusive. Application as micronizer disc, pump wear com-ponent and antiabrasion slab.

THERMALLY-INSULATING COMPONENTS MADE OF THERMALLY-STABILIZED REFRACTORY CERAMIC FIBERS

The invention relates to a refractory thermally-insulating component consisting essentially of refractory ceramic fibers which are mechanically combined with one another, the composition of which comprises at least 97.5% by weight of alumina, silica and zirconia in total, wherein: a) no organic or inorganic binder binds the fibers to one another; b) the fibers have the following chemical composition, as % by weight: Al2O3 : 33-45% SiO2 : 41-53 % ZrO2 : 5.5-17% MgO : 0.02-2% other oxides: < 0.50% with Fe2O3 + TiO2 ? 0.20% and Na2O + CaO + K2O ? 0.30%; c) the said fibers homogeneously have, throughout the entire body of the component, a degree of crystallinity of not less than 30% and not more than 64%, the crystals present being essentially formed of mullite crystals and of quadratic zirconia; and d) the said component has a linear shrinkage of no more than 3% after being held for 24 hours at 1450°C.

REACTIVE DERIVATIVE OF ZIRCONIUM AND ITS PREPARATION

The invention relates to the chemistry of zirconium. It relates to reactive derivatives of zirconium, characterized in that they are in the form of a pulverulent white solid which is not crystallized and dry in appearance, and consist of metazirconic acid ZrO(OH)2 accompanied by free or weakly bound water, it being possible for some of the OH- ions to be replaced by halide ions, the ZrO2 content of these derivatives being from 60 to 92% by weight inclusive and the water content of these derivatives ranging from 3 to 40% and the halide ion content of these derivatives being capable of ranging up to approximately 5% by weight, and to a process for their preparation. The solid derivatives of the invention can be easily converted into usual reactive derivatives of zirconium by reaction with an aqueous solution of an acid.

PROCESS FOR THE MANUFACTURE OF ZIRCONIUM OXIDE HYDRATE FROM GRANULAR CRYSTALLIZED ZIRCONIUM OXIDE

The invention relates to inorganic chemistry. It relates to a process for the preparation of zirconia hydrate from granular crystallized ZrO2 by reaction of the latter with solid sodium hydroxide at 550-1,400.degree.C to form Na zirconate, by hydrolysis of the latter to form a suspension of zirconia hydrate in aqueous sodium hydroxide, by separation of most of the aqueous sodium hydroxide, by treatment of the zirconia hydrate containing residual aqueous sodium hydroxide with an ammonium salt, and by separation, washing and dewatering of the purified zirconia hydrate obtained. The zirconia hydrate can be used for the preparation of zirconium compounds.

Heat-insulating elements containing refractory ceramic fibres thermically stabilized

L'invention concerne un élément thermiquement isolant réfractaire formé pour l'essentiel de fibres céramiques réfractaires mécaniquement associées entre elles, dont la composition comprend au moins 97,5% en poids d'alumine, de silice et de zircone au total, caractérisé en ce que: a) aucun liant organique ou minéral ne lie les fibres entre elles; b) les fibres ont la composition chimique suivante, en % en poids: (CF DESSIN DANS BOPI) autres oxydes: 2 O3 + TiO2 <= 0,20 % et Na2 O + CaO + K2 O <= 0,30 %; c) lesdites fibres présentent de façon homogène dans toute la masse de l'élément un taux de cristallinité d'au moins 30 % et d'au plus 64 %, les cristaux présents étant essentiellement formés de cristaux de mullite et de zircone quadratique; et d) ledit élément présente un retrait linéaire d'au plus 3 % après maintien pendant 24 heures à 1450 degréC. The invention relates to a heat-insulating refractory element formed essentially of refractory ceramic fibers mechanically associated with one another, the composition of which comprises at least 97.5% by weight of alumina, silica and zirconia in total, characterized in that that: a) no organic or inorganic binder binds the fibers together; b) the fibers have the following chemical composition, in% by weight: (CF DRAWING IN BOPI) other oxides: 2 O3 + TiO2 <= 0.20% and Na2 O + CaO + K2 O <= 0.30%; c) said fibers exhibit homogeneously throughout the mass of the element a degree of crystallinity of at least 30% and at most 64%, the crystals present being essentially formed of crystals of mullite and of quadratic zirconia; and d) said element exhibits a linear shrinkage of at most 3% after holding for 24 hours at 1450 ° C.

Fused ceramic beads

Porous ceramic products of titanium sub-oxides

The invention relates to a method for manufacturing porous products made up essentially of titanium sub-oxide(s) with generic formulation TiOx, the value of x being from 1.6 to 1.9, said method comprising the following steps: a) mixing raw materials comprising at least one source of titanium dioxide, a reducing agent comprising carbon; b) shaping the product; c) optionally, in particular when organic products are used during step a), thermal treatment in air or oxidising atmosphere; d) sintering, for example at a temperature higher than 1150°C but not exceeding 1430°C, under a neutral or reducing atmosphere, in which the source of titanium dioxide is made up of at least 55 wt% of anatase. The invention also relates to a product that can be obtained by such a method.

YELLOW PIGMENT PRASEODYMIUM ZIRCON-OXYDE AND COMPOSITION FOR SA MANUFACTURE

L'invention concerne un pigment jaune caractérisé en ce qu'il présente l'analyse chimique suivante, en % en poids sur la base des (CF DESSIN DANS BOPI) Utilisation notamment pour la coloration de matières céramiques.

Hip joint prosthesis having a zirconia head and a ceramic cup

ARTICLES OF CERAMIC MATERIAL

PURPOSE: To improve the mechanical strength and wear resistance of articles of specific thicknesses obtainable by melting and casting an Al2O3-ZrO2-SiO2-K2O based compsn. by specifying the texture and compsn. of these articles. CONSTITUTION: The articles of the ceramic material have thicknesses of at least 30 mm or below in part thereof and consist of a crystalline corundum, zirconia phase and glass phase. The zirconia is in substantially monoclinic form from the cores to the surface layers of the articles and the compsn. described above is shown below: I.e., the compsn. is, by weight % based on oxides, 40 to 75 Al2O3, 20 to 45 ZrO2, 5 to 20 SiO2, 0 to 2.7 Na2O, 0.15 to 4.25 K2O and 0 to 0.3 Fe2O3+TiO2+CaO+MgO and the weight ratio (Na2O+K2O/1.52/ SiO2 is 0.07 to 0.14. COPYRIGHT: (C)1989,JPO ...

VERFAHREN ZUR HERSTELLUNG VON HYDRATIERTEM ZIRKONIUMOXID AUS GRANULIERTEM KRISTALLINEM ZIRKONIUMOXID.

THIN CERAMIC ARTICLES OBTAINED FUSING AND CASTING IN A MOLD A COMPOSITION OF THE SYSTEM AL2O-ZRO2-SIO2-K2O WHICH HAVE GOOD MECHANICAL STRENGTH AND ABRASION RESISTANCE PROPERTIES

Kugeln aus geschmolzenen keramischen Werkstoff

Fused ceramic balls have compsn. (by wt.) 40-95% ZrO2 + HfO2; 0.1-25% total of 0.1-10% Y2O3 and/or 1-15% CeO2; and either 10-45% SiO2, when CeO2 is absent, or 0.5-45% SiO2 when CeO2 is present.

REFRACTORY THERMALLY INSULATING MEMBER

PURPOSE: To obtain a refractory thermally insulating member which can be continuously used at higher temp. than conventional thermally insulating member, and which can maintain other desired properties of the member. CONSTITUTION: This refractory thermally insulating member is produced from fibers having a compsn. containing at least 97.5 wt.% alumina, silica and zirconia, wherein: (a) no org. or inorg. binder finds the fibers to one another; (b) the fibers have a compsn. of 33 to 45 wt.% Al2O3, 41 to 53 wt.% SiO2, 5.5 to 17 wt.% ZrO2, 0.02 to 2 wt.% MgO, and other oxides satisfying Fe2O3+ TiO2≤0.20 wt.% and Na2O+CaO+K2O≤0.30 wt.%; (c) the fibers homogeneously have 30 to 64% cryotallinity all over the member and consist of mullite crystals and quadratic zirconia; and (d) the member shows ≤3% linear shrinkage after being held at 1,450°C for 24 hours. COPYRIGHT: (C)1995,JPO ...

REACTIVE DERIVATIVE OF ZIRCONIUM AND ITS PREPARATION

PURIFICATION STRUCTURE INCORPORATING AN ELECTROCHEMICAL CATALYSIS SYSTEM

The invention relates to a structure for the purification of a contaminated gas, for example the exhaust gas from a diesel or petrol engine, the structure incorporating an electrochemical system for treating said gas, composed of an NOreduction catalyst A, a hydrocarbon oxidation catalyst B, an electron-conducting compound C and an ion-conducting compound D, said structure being characterized in that it is made of or covered with at least one porous, inorganic, electron-conducting and/or ion-conducting material in such a way that the catalysts A and B are disposed in the porosity of the inorganic material and that the ion-conducting, electron-conducting or ion-conducting and electron-conducting inorganic material makes up, respectively, the element C, the element D, or the sum of the elements C and D of said electrochemical system.x © KIPO & WIPO 2009 ...

FUSED CERAMIC BEADS

PURPOSE: To provide the beads produced from a fused ceramic material having an excellent quality and useful as grinding and dispersing medium especially. CONSTITUTION: The fused ceramic beads has the following chemical composition in wt.% on the basis of oxide. 40-95% ZrO2 and HfO2 and at least one of Y2O3 and CeO2 being an additional oxide, but the amount is 0.1-10% when Y2O3 is present and 1-15% when CeO2 is present. The total of Y2O3 and CeO2 is 0.1-25%, and an amount of SiO2 is 10-45% of the composition when CeO2 is absent and 0.5-45% when CeO2 is present. COPYRIGHT: (C)1995,JPO ...

Purification structure incorporating an electrochemical catalysis system

The invention relates to a structure for the purification of a contaminated gas, for example the exhaust gas from a diesel or petrol engine, the structure incorporating an electrochemical system for treating said gas, composed of an NOx reduction catalyst A, a hydrocarbon oxidation catalyst B, an electron-conducting compound C and an ion-conducting compound D, said structure being characterized in that it is made of or covered with at least one porous, inorganic, electron-conducting and/or ion-conducting material in such a way that the catalysts A and B are disposed in the porosity of the inorganic material and that the ion-conducting, electron-conducting or ion-conducting and electron-conducting inorganic material makes up, respectively, the element C, the element D, or the sum of the elements C and D of the electrochemical system.

COLORED SINTERED ZIRCONIA

An article with a sintered decorative part obtained from a particulate mixture having the following chemical composition: 1. A decorative article comprising a sintered part obtained from a particulate mixture having a chemical composition comprising , as percentages by weight based on the oxides:{'sub': '2', 'zirconia ZrO: complement to 100%;'}0.5% to 10.0% of oxide(s) with a perovskite structure;{'sub': 2', '3', '2', '3', '2, '2.0% to 20.0% of a stabilizer for zirconia selected from the group consisting of YO, ScO, MgO, CaO, CeO, and mixtures thereof, a quantity MgO+CaO being less than 5.0%;'}{'sub': 2', '3', '2, 'less than 2.0% of a sintering additive selected from the group consisting of AlO, ZnO, TiO, and mixtures thereof; and'}less than 2.0% of other oxides;wherein the oxide(s) with a perovskite structure and/or said stabilizer and/or said sintering additive are optionally replaced, completely or in part, by an equivalent quantity of precursor(s) of said oxides.2. The article according to claim 1 , having a surface of roughness Ra that is less than 0.05 μm claim 1 , or is in a range of from 0.1 μm to 0.5 μm.3. The article according to claim 1 , said mixture comprising 0.5% to 10.0% claim 1 , as a percentage by weight based on the oxides claim 1 , of an oxide with a perovskite structure and/or a precursor of said oxide wherein:{'sub': 'A', 'an A-element at an A-site of the perovskite structure of said oxide is selected from the group G(1) consisting of calcium, strontium, barium, lanthanum, praseodymium, neodymium, bismuth, cerium, and mixtures thereof; and'}{'sub': 'B', 'a B-element at a B-site of the perovskite structure of said oxide is selected from the group G(1) consisting of a mixture of cobalt and iron, a mixture of cobalt and manganese, a mixture of cobalt and chromium, a mixture of cobalt and nickel, a mixture of chromium and manganese, a mixture of chromium and nickel, a mixture of chromium and iron, a mixture of manganese and iron, a mixture of ...

Colored sintered zirconia

An article with a sintered decorative part obtained from a particulate mixture having the following chemical composition: zirconia ZrO2: complement to 100%; 0.5% to 10.0% of oxide(s) with a perovskite structure; 2.0% to 20.0% of a stabilizer for zirconia selected from Y2O3, Sc2O3, MgO, CaO, CeO2, and mixtures thereof, the quantity MgO+CaO being less than 5.0%; less than 2.0% of a sintering additive selected from Al2O3, ZnO, TiO2, and mixtures thereof; and less than 2.0% of other oxides.

Thermisch stabile Isolierbauteile aus feuerfesten Keramikfasern

AKTIVES DERIVAT VON ZIRKONIUM UND SEINE HERSTELLUNG.

PROCESS FOR MANUFACTURE OF ZIRCONIUM OXIDE HYDRATE FROM GRANULAR CRYSTALLIZED ZIRCONIUM OXIDE

Kugeln aus geschmolzenen keramischen Werkstoff

DUENNE KERAMISCHE TEILE, ERHALTEN DURCH SCHMELZEN UND GIESSEN EINER ZUSAMMENSETZUNG AUS DEM SYSTEM AL2O3-ZRO2-SIO2-K2O.

DUENNE KERAMISCHE TEILE, ERHALTEN DURCH SCHMELZEN UND GIESSEN EINER ZUSAMMENSETZUNG AUS DEM SYSTEM AL2O3-ZRO2-SIO2-K2O.

AKTIVES DERIVAT VON ZIRKONIUM UND SEINE HERSTELLUNG.

NTER VERWENDUNG VON PORENBILDENDEN MITTELN AUF SILIZIUMBASIS

Filters comprising oxygen-depleted SiC membranes

A filter for the filtration of a fluid, such as a liquid, includes or composed of a support element made of a porous ceramic material, the element having a tubular or parallelepipedal shape delimited by an external surface and including, in its internal portion, a set of adjacent channels with axes parallel to one another and separated from one another by walls of the porous inorganic material, wherein at least a portion of the channels and/or at least a portion of the external surface are covered with a porous separating membrane layer, wherein the layer is made of a material essentially composed of sintered grains of silicon carbide (SiC), and the weight content of elemental oxygen of the layer is less than 0.5%.

REAKTIVES ZIRKONIUMOXID UND SEINE HERSTELLUNG.

REACTIVE ZIRCONIUM OXIDE AND ITS PRODUCTION

PURPOSE: To make it possible to execute sintering in a short time at a low temp. by forming a reactive zirconium oxide having a structure which is amorphous and crystallized in the tetragonal form and having a specific medium diameter and B.E.T. specific surface area as well as the size of the elementary coherence regions of crystals. CONSTITUTION: A relatively nonreactive zirconium oxide, for example, thermal zirconium oxide and an alkali metal hydroxide or carbonate, more preferably pellet-like NaOH more excessive than a stoichiometry are brought into reaction for 30 minutes to 1 hour at 600 to 950°C, by which an alkali metal salt is obtd. After this salt is hydrolyzed with hot water, the alkali is filtered and removed from the slurry of the formed zirconium oxide hydrate. The filtrate is washed and is further washed with an NH4Cl soln. The filtrate is thereafter dried at 350 to 450°C, by which the reactive zirconium oxide is obtd. This ZrO2 has the structure which is amorphous or crystallized ...

Fused ceramic beads

COMMUNICATION DEVICE

The invention relates to a communication device using radio waves with frequencies of 800 MHz to 3 GHz, comprising a ceramic cover at least partially exposed to the external environment of the device, at least one portion of said waves passing therethrough during the use of the device, said cover being at least partially made of a sintered product having a chemical composition such as, by weight and for a total of 100 %: 32 % <= ZrO2 <= 95 %, 1 % < Y2O3+CeO2+Sc2O3+MgO+CaO, 0 % <= CeO2 <= 26 %, 0 % <= MgO <= 43 %, 0 % <= CaO <= 37 %, 0 % <= SiO2 <= 41 %, 0 % <= Al2O3 <= 55 %, 0 % <= TiO2 <= 30 %, 0 % <= lanthanide oxides, except for CeO2 <= 50 %, 0 % <= SrO <= 24 %, 0 % <= SiAlON compounds <= 50 %, and other compounds <= 15 %.

POROUS CERAMIC PRODUCTS OF TITANIUM SUB-OXIDES

Method for manufacturing porous products consisting essentially of titanium suboxide(s) of general formula TiOx, the value of x being between 1.6 and 1.9, the method including a) mixing the raw materials including at least one source of titanium dioxide, a reducing agent comprising carbon, b) forming the product, c) optionally, in particular when organic products are used during step a), thermal treatment under air or an oxidizing atmosphere, d) sintering, for example at a temperature above 1150° C. but not exceeding 1430° C., under a neutral or reducing atmosphere, in which the source of titanium dioxide consists of at least 55 wt % of anatase.

Coloured sintered zirconia

Article comprising a decorative sintered item obtained from a particulate mixture exhibiting the following chemical composition: zirconia ZrO2: remainder to 100%; from 0.5 to 10.0% of oxide(s) of perovskite structure; from 2.0 to 20.0% of a stabilizer of the zirconia chosen from the group formed by Y2O3, Sc2O3, MgO, CaO, CeO2 and their mixtures, the MgO+CaO content being less than 5.0%; less than 2.0% of a sintering additive chosen from the group formed by Al2O3, ZnO, TiO2 and their mixtures; less than 2.0% of other oxides.

COMMUNICATION DEVICE

The invention relates to a communication device using radio waves with frequencies of 800 MHz to 3 GHz, comprising a ceramic cover at least partially exposed to the external environment of the device, at least one portion of said waves passing therethrough during the use of the device, said cover being at least partially made of a sintered product having a chemical composition such as, by weight and for a total of 100%, 32%≦ZrO≦95%, 1% Подробнее

REACTIVE DERIVATIVE OF ZIRCONIUM AND ITS PREPARATION

Method for preparing a porous structure using silica-based pore-forming agents

The present invention relates to a method for preparing a porous structure using silica-based pore-forming agents. The invention concerns a method for making a honeycomb-type silicon carbide porous structure, said method being characterized in that it includes the following steps: forming a paste from a mixture of silicon carbide grains whereof the diameter d50 ranges between 5 [mu]m and 300 [mu]m, of an organic binder, in the form of silica-based particles whereof the global porosity is higher than 70 %, shaping a crude honeycomb-shaped plastic monolith, drying said monolith and curing the monolith up to a temperature higher than 2100 DEG C. The structure obtained by the method may be used as catalytic support in a diesel or gas engine exhaust line or as particulate filter in a diesel engine exhaust line.

NEW REACTIVE DERIVATIVE OF ZIRCONIUM AND ITS PRODUCTION

PURPOSE: To provide an extremely stable reactive deriv. of zirconium which is a slid material contg. the least possible impurities and water, is usable as a Zr supply source for various industrial applications and has a high ZrO2 content. CONSTITUTION: This reactive deriv. of the zirconium is not crystallized, is dry in appearance and is soluble in an aq. acid soln. The reactive deriv. is in the form of pulverulent white solid consisting of metazirconic acid ZrO(OH)2 accompanied by free or weakly bound water substituted by halogen ions for some OH- ions. The ZrO2 content of the deriv. is 60 to 92 wt.% and the water content is 3 to 40%. The halogen on content thereof is within a range up to about 5%. The halogen is preferably Cl- ions. The deriv. described above is obtd. by preparing a zirconia hydrate ZrO2.2H2O rich in water, i.e., zirconium hydroxide Zr(OH)4, subjecting the same to controlled heating until the pulverulent white solid which is non-crystallized, is dry in appearance and ...

Porous ceramic products of titanium sub-oxides

Method for manufacturing porous products consisting essentially of titanium suboxide(s) of general formula TiOx, the value of x being between 1.6 and 1.9, the method including a) mixing the raw materials including at least one source of titanium dioxide, a reducing agent comprising carbon, b) forming the product, c) optionally, in particular when organic products are used during step a), thermal treatment under air or an oxidizing atmosphere, d) sintering, for example at a temperature above 1150° C. but not exceeding 1430° C., under a neutral or reducing atmosphere, in which the source of titanium dioxide consists of at least 55 wt % of anatase.

SINTERED CERAMIC COMPONENT AND A PROCESS OF FORMING THE SAME

A sintered ceramic component can have a final composition including at least 50 wt. % MgO and at least one desired dopant, wherein each dopant of the at least one desired dopant has a desired dopant content of at least 0.1 wt. %. All impurities (not including the desired dopant(s)) are present at a combined impurity content of less than 0.7 wt. %. A remainder can include AlO. The selection of dopants can allow for better control over the visual appearance of the sintered ceramic component, reduces the presence of undesired impurities that may adversely affect another part of an apparatus, or both. The addition of the dopant(s) can help to improve the sintering characteristics and density as compared to a sintered ceramic component that includes the material with no dopant and a relatively low impurity content. 1. A sintered ceramic component having a final composition comprising:at least 50 wt. % MgO;at least one desired dopant, wherein each dopant of the at least one desired dopant has a desired dopant content of at least 0.1 wt. %;all impurities are present at a combined impurity content of less than 0.7 wt. %; and{'sub': 2', '3, 'a remainder comprising AlO.'}2. The sintered ceramic component of claim 1 , wherein the at least one desired dopant includes CaO.3. The sintered ceramic component of claim 2 , wherein the CaO content is at least 0.2 wt. %.4. The sintered ceramic component of claim 1 , wherein the at least one desired dopant includes YO.5. The sintered ceramic component of claim 4 , wherein the YOcontent is no greater than 3 wt. %.6. The sintered ceramic component of claim 1 , wherein the at least one desired dopant includes TiO.7. The sintered ceramic component of claim 6 , wherein the TiOcontent is no greater than 3 wt. %8. The sintered ceramic component of claim 1 , wherein the at least one dopant includes a first dopant and a second dopant.9. The sintered ceramic component of claim 1 , wherein MgO has a content that is in a range of 51 wt. % to 80 wt. ...

SINTERED CERAMIC COMPONENT AND A PROCESS OF FORMING THE SAME

A sintered ceramic component can have a final composition including at least 50 wt. % MgO and at least one desired dopant, wherein each dopant of the at least one desired dopant has a desired dopant content of at least 0.1 wt. %. All impurities (not including the desired dopant(s)) are present at a combined impurity content of less than 0.7 wt. %. A remainder can include AlO. The selection of dopants can allow for better control over the visual appearance of the sintered ceramic component, reduces the presence of undesired impurities that may adversely affect another part of an apparatus, or both. The addition of the dopant(s) can help to improve the sintering characteristics and density as compared to a sintered ceramic component that includes the material with no dopant and a relatively low impurity content. 1. A sintered ceramic component , comprising:at least 50 wt. % MgO;{'sub': '2', 'at least one desired dopant including CaO, TiO, or a combination thereof, wherein each dopant of the at least one desired dopant has a desired dopant content of at least 0.1 wt. %, and'}all impurities are present at a combined impurity content of less than 0.7 wt. %,{'sub': 2', '4, 'wherein the sintered ceramic component comprises MgAlOand has a density that is at least 90% of theoretical density.'}2. The sintered ceramic component of claim 1 , wherein the density is at least 94% of the theoretical density.3. The sintered ceramic component of claim 1 , wherein MgO is in a content from 50 wt. % to 80 wt. %.4. The sintered ceramic component of claim 1 , wherein the desired dopant content is in a range of 0.2 wt. % to 5 wt. %.5. The sintered ceramic component of claim 1 , wherein the at least one desired dopant includes CaO.6. The sintered ceramic component of claim 5 , wherein CaO is in a content of at least 0.2 wt. %.7. The sintered ceramic component of claim 1 , wherein the at least one desired dopant includes TiO.8. The sintered ceramic component of claim 7 , wherein TiOis in a ...

FILTERS COMPRISING OXYGEN-DEPLETED SiC MEMBRANES

A filter for the filtration of a fluid, such as a liquid, includes or composed of a support element made of a porous ceramic material, the element having a tubular or parallelepipedal shape delimited by an external surface and including, in its internal portion, a set of adjacent channels with axes parallel to one another and separated from one another by walls of the porous inorganic material, wherein at least a portion of the channels and/or at least a portion of the external surface are covered with a porous separating membrane layer, wherein the layer is made of a material essentially composed of sintered grains of silicon carbide (SiC), and the weight content of elemental oxygen of the layer is less than 0.5%. 1. A filter for the filtration of a fluid , comprising or composed of a support element made of a porous ceramic material , said support element having a tubular or parallelepipedal shape delimited by an external surface and comprising , in its internal portion , a set of adjacent channels with axes parallel to one another and separated from one another by walls of said porous inorganic material , wherein:at least a portion of said channels are covered on their internal surface with a porous separating membrane layer and/orat least a portion of said external surface is covered with a porous separating membrane layer;said porous separating membrane layer is made of a material essentially composed of sintered grains of silicon carbide (SiC),a weight content of elemental oxygen of the porous separating membrane layer is less than 0.5%.2. The filter as claimed in claim 1 , wherein the SiC represents more than 97% of the weight of the material constituting the porous separating membrane layer.3. The filter as claimed in claim 1 , wherein an atomic concentration of oxygen measured by XPS at a surface of the SiC grains is less than 10% claim 1 , on the basis of the total amount of the elements Si claim 1 , C and O.4. The filter as claimed in claim 1 , wherein a ...

Hip joint prosthesis having a zirconia head and a ceramic cup

This invention relates to a biojoint prosthesis comprising: a) a prosthetic comprising a first component having an outer surface comprising at least 90 mol% zirconia, and b) a second component having a surface shaped to receive the outer surface of the first component, wherein the outer surface of the first component is received on the surface of the second component, and wherein a) at least a portion of the surface of the second component receiving the first component comprises a ceramic having a surface roughness of no more than 100 nm, and b) the outer surface of the first component has a surface roughness of no more than 100 nm.

REACTIVE ZIRCONIUM OXIDE AND ITS PREPARATION

COLORED FRITTED ZIRCONIA.

Mélange particulaire présentant la composition chimique suivante, en pourcentages massiques sur la base des oxydes : - zircone ZrO : complément à 100% ; - 0,5 à 10.0% d'oxyde(s) de structure pérovskite ; - 2,0 à 20,0% d'un stabilisant de la zircone choisi dans le groupe formé par Y O , SC O , MgO, CaO, CeO et leurs mélanges, la teneur MgO + CaO étant inférieure à 5,0% ; - moins de 2,0% d'un additif de frittage choisi dans le groupe formé par Al O , ZnO, TiO et leurs mélanges; - moins de 2,0% d'autres oxydes le ou les oxyde(s) de structure pérovskite et/ou ledit stabilisant et/ou ledit additif de frittage pouvant être remplacés, totalement ou en partie, par une quantité équivalente de précurseur(s) de ces oxydes. Particulate mixture having the following chemical composition, in weight percentages based on the oxides: zirconia ZrO: 100% complement; 0.5 to 10.0% of oxide (s) of perovskite structure; 2.0 to 20.0% of a zirconia stabilizer selected from the group consisting of Y 0, SC O, MgO, CaO, CeO and mixtures thereof, the MgO + CaO content being less than 5.0%; less than 2.0% of a sintering additive selected from the group consisting of AlO, ZnO, TiO and mixtures thereof; less than 2.0% of other oxides, the oxide (s) of perovskite structure and / or said stabilizer and / or said sintering additive being able to be replaced, totally or partially, by an equivalent quantity of precursor (s); ) of these oxides.

STRUCTURE FOR GAS FILTRATION AND NOX REDUCTION.

L'invention se rapporte à une structure de filtration (1) de gaz chargés en particules et en polluants gazeux, du type en nid d'abeilles et comprenant un ensemble de canaux (2,3) adjacents longitudinaux d'axes parallèles entre eux séparés par des parois (6) poreuses filtrantes, ladite structure se caractérisant en ce que une première portion (6") des parois (6) des canaux, dans une partie située à l'extrémité aval (5) du filtre, est perméable aux gaz à traiter et présente une porosité ouverte comprise entre 30 et 80%, une deuxième portion (6') des parois des canaux, dans une partie située à l'extrémité amont (4) du filtre, présente, au moins en surface des canaux d'entrée (3), une porosité inférieure celle de ladite portion (6") située à l'extrémité aval du filtre, ladite portion (6') de parois de plus faible porosité, dans la partie située à l'extrémité amont du filtre, étant recouverte de et/ou incorporant un système catalytique (8) de réduction des NOx ou un système du type SCR. The invention relates to a filtration structure (1) of gaseous particulate and gaseous pollutant gases, of the honeycomb type and comprising a set of longitudinal adjacent channels (2,3) of mutually parallel axes. by porous filtering walls (6), said structure being characterized in that a first portion (6 ") of the walls (6) of the channels, in a portion located at the downstream end (5) of the filter, is permeable to gases to be treated and has an open porosity between 30 and 80%, a second portion (6 ') of the walls of the channels, in a portion located at the upstream end (4) of the filter, has, at least on the surface of the channels of input (3), a porosity lower than that of said portion (6 ") located at the downstream end of the filter, said portion (6 ') of walls of lower porosity, in the portion located at the upstream end of the filter , being coated with and / or incorporating a catalytic reduction system (8) of s ...

NEW REACTIVE ZIRCONIUM DERIVATIVE AND ITS PREPARATION

STRUCTURE FOR GAS FILTRATION AND NOX REDUCTION.

ORIENTED PARTICLE PRODUCT

Dispositif choisi notamment parmi une turbine, notamment pour la propulsion et pour la génération d'énergie, un moteur, une pompe, un effecteur, un capteur, une poignée, un joint, notamment un joint d'étanchéité, un rail de coulissement, un roulement, notamment une bille de roulement, une cage de roulement, une pièce ou un revêtement anti-usure, une buse de pulvérisation, un étrier, un robinet, une valve, un guide-fils, une bague de frottement, une armure ou élément d'armure, un blindage ou élément de blindage, un outil de formage des métaux, un outil de formage des polymères, notamment une filière, un moule d'injection, un élément d'emballage, notamment une cale, un composant électrique ou électronique, notamment une varistance, un condensateur, et un substrat pour composant électronique, ledit dispositif comportant un produit dense, éventuellement fritté, présentant une masse volumique relative supérieure à 85%, comportant plus de 50% de grains céramiques orientables, plus de 80% de grains céramiques orientables étant sensiblement parallèles les uns aux autres.

COMMUNICATION DEVICE

TITANIUM SUB OXIDES CERAMIC PRODUCTS

Procédé de fabrication de produits poreux constitués essentiellement de sous-oxyde(s) de titane de formulation générique TiOx, la valeur de x étant comprise entre 1,6 et 1,9, ledit procédé comprenant les étapes suivantes : a) mélange des matières premières comprenant au moins une source de dioxyde de titane, un agent réducteur comprenant du carbone, b) mise en forme du produit, c) optionnellement, notamment lorsque des produits organiques sont utilisés au cours de l'étape a), traitement thermique sous air ou atmosphère oxydante, d) frittage, par exemple à une température supérieure à 1150°C mais ne dépassant pas 1430°C, sous une atmosphère neutre ou réductrice, dans lequel la source de dioxyde de titane est constituée d'au moins 55% poids d'anatase. Produit susceptible d'être obtenu par un tel procédé. Process for manufacturing porous products consisting essentially of titanium sub-oxide(s) of generic TiOx formulation, the value of x being between 1.6 and 1.9, said process comprising the following steps: a) mixing the raw materials comprising at least one source of titanium dioxide, a reducing agent comprising carbon, b) shaping of the product, c) optionally, in particular when organic products are used during step a), heat treatment in air or oxidizing atmosphere, d) sintering, for example at a temperature above 1150°C but not exceeding 1430°C, under a neutral or reducing atmosphere, in which the source of titanium dioxide consists of at least 55% by weight of anatase. Product obtainable by such a process.

REACTIVE ZIRCONIUM OXIDE AND ITS PREPARATION

L'invention se rapporte à la chimie du zirconium. Elle concerne notamment un oxyde de zirconium réactif sous forme de particules fines dont le diamètre médian n'excède pas 10 mum caractérisé en ce qu'il a une structure choisie parmi la structure amorphe et la structure cristallisée sous la forme tétragonale, la taille des domaines élémentaires de cohérence dans ce dernier cas étant comprise entre 10 et 30 nm, et en ce qu'il a une surface spécifique B.E.T. d'au moins 30 m**2/g, ainsi qu'un procédé pour sa préparation. Utilisation dans le domaine des matières céramiques. The invention relates to the chemistry of zirconium. It relates in particular to a reactive zirconium oxide in the form of fine particles, the median diameter of which does not exceed 10 μm, characterized in that it has a structure chosen from the amorphous structure and the crystalline structure in the tetragonal form, the size of the domains. elementary coherence in the latter case being between 10 and 30 nm, and in that it has a specific BET surface of at least 30 m ** 2 / g, as well as a process for its preparation. Use in the field of ceramic materials.

PROCESS FOR PRODUCING HYDRATED ZIRCONIUM OXIDE FROM GRANULAR CRYSTALLIZED ZIRCONIUM OXIDE

L'invention se rapporte à la chimie minérale. Elle concerne un procédé de préparation de zircone hydratée à partir de ZrO2 cristallisé granulaire par réaction de ce dernier avec de la soude solide à 550-1400degre(s)C pour former du zirconate de Na, par hydrolyse de ce dernier pour former une suspension de zircone hydratée dans de la soude aqueuse, par séparation de la majeure partie de la soude aqueuse, par traitement de la zircone hydratée contenant de la soude aqueuse résiduelle avec un sel d'ammonium, et par séparation, lavage et essorage de la zircone hydratée purifiée obtenue. La zircone hydratée est utile pour la préparation de composés du zirconium. The invention relates to inorganic chemistry. It relates to a process for preparing hydrated zirconia from granular crystallized ZrO2 by reacting the latter with solid sodium hydroxide at 550-1400degre (s) C to form Na zirconate, by hydrolysis of the latter to form a suspension of zirconia hydrated in aqueous sodium hydroxide, by separating the major part of the aqueous sodium hydroxide, by treating the hydrated zirconia containing residual aqueous sodium hydroxide with an ammonium salt, and by separating, washing and dewatering the purified hydrated zirconia obtained. Hydrated zirconia is useful for the preparation of zirconium compounds.

Colored sintered zirconia

The invention relates to an item comprising a decorative sintered part obtained from a particulate mixture having the following chemical composition: zirconia ZrO 2 : the remainder up to 100%; 0.5 to 10.0% oxides having a perovskite structure; 2.0 to 20.0% of a zirconia stabilizer selected from the group consisting of Y 2 O 3 , Sc 2 O 3 , MgO, CaO, CeO 2 , and the mixtures thereof, the MgO + CaO content being less than 5.0%; less than 2.0% of a sintering additive selected from the group consisting of Al 2 O 3 , ZnO, TiO 2 , and the mixtures thereof; and less than 2.0% of other oxides.

Melted ceramic balls.

Sintered ceramic component and a process of forming the same

A sintered ceramic component can have a final composition including at least 50 wt.% MgO and at least one desired dopant, wherein each dopant of the at least one desired dopant has a desired dopant content of at least 0.1 wt.%. All impurities (not including the desired dopant(s)) are present at a combined impurity content of less than 0.7 wt.%. A remainder can include A1 2 O 3 . The selection of dopants can allow for better control over the visual appearance of the sintered ceramic component, reduces the presence of undesired impurities that may adversely affect another part of an apparatus, or both. The addition of the dopant(s) can help to improve the sintering characteristics and density as compared to a sintered ceramic component that includes the material with no dopant and a relatively low impurity content.

COLORED FRITTED ZIRCONIA.

Method for preparing a porous structure using silica-based pore-forming agents

Heat-insulating elements based on thermally stabilized refractory ceramic fibers.

Reactive zirconium oxide and its preparation

A process for the preparation of improved zirconium oxides comprising A) providing a zirconium oxide which has been produced by thermal decomposition of zircon followed by chemical digestion of the resultant silicate phases, B) reacting the zirconium oxide at high temperature with an alkali metal hydroxide or carbonate so as to form an alkali metal zirconate, C) hydrolyzing the resultant alkali metal zirconate so as to produce a suspension of zirconium oxide hydrate in a concentrated solution of alkali metal hydroxide, D) separating the zirconium oxide hydrate from the concentrated solution and washing the zirconium oxide hydrate which has been isolated, and E) drying the zirconium oxide hydrate at a temperature in the range of from 110° to 570° C.

ZIRCONIA AND SILICA BASE AGENT FOR DEEP GEOLOGICAL FRACTURES

L'INVENTION SE RAPPORTE AU DOMAINE DE L'EXTRACTION PETROLIERE. ELLE CONCERNE, PLUS PRECISEMENT, UN AGENT DE SOUTENEMENT GRANULAIRE A HAUTE RESISTANCE MECANIQUE, D'UNE MASSE VOLUMIQUE INFERIEURE A 3250KGM, CARACTERISE EN CE QU'IL EST CONSTITUE DE BILLES FORMEES PAR FUSION, GRANULATION ET SOLIDIFICATION, D'UNE COMPOSITION DE DEPART COMPRENANT, EN POIDS SUR LA BASE DES OXYDES, 46 A 50 PARTIES DE ZRO, 54 A 50 PARTIES DE SIO, LA SOMME DE ZRO SIO TOTALISANT 100 PARTIES, 0 A 19 PARTIES D'ALO ET 0 A 13,5 PARTIES D'AU MOINS UN OXYDE CHOISI DANS LE GROUPE FORME PAR MGO, CAO, FEO ET TIO. UTILISATION PAR LES PETROLIERS.

FILTERS COMPRISING OXYGEN BASED SIC MEMBRANES

Filtre pour la filtration d'un fluide tel qu'un liquide, comprenant ou constitué par un élément support (1) fait dans un matériau céramique poreux, ledit élément présentant une forme tubulaire ou parallélépipédique délimitée par une surface externe (2) et comprenant dans sa portion interne (3) un ensemble de canaux (4) adjacents, d'axes parallèles entre eux et séparés les uns des autres par des parois (8) dudit matériau inorganique poreux, dans lequel au moins une partie desdits canaux (4) et/ou au moins une partie de ladite surface externe sont recouverts d'une couche séparatrice membranaire (5) poreuse, ledit filtre étant caractérisé en ce que : - ladite couche est faite dans un matériau constitué essentiellement de grains frittés de carbure de silicium (SiC), - la teneur massique en oxygène élémentaire de la couche est inférieure à 0,5%. Filter for the filtration of a fluid such as a liquid, comprising or consisting of a support element (1) made of a porous ceramic material, said element having a tubular or parallelepipedal shape delimited by an external surface (2) and comprising in its inner portion (3) a set of adjacent channels (4), axes parallel to each other and separated from each other by walls (8) of said porous inorganic material, wherein at least a portion of said channels (4) and / or at least a portion of said outer surface are covered with a porous membrane-separating layer (5), said filter being characterized in that: - said layer is made of a material consisting essentially of sintered grains of silicon carbide (SiC ) - the elemental oxygen content of the layer is less than 0.5%.

PIGMENT SUITABLE FOR INKJET PRINTING

Pigment sous la forme d'une poudre de particules, présentant une teneur massique en zircon supérieure ou égale à 80% sur la base de la masse sommée des phases de zircon et de zircone cristallisées présentes dans ledit pigment, ledit pigment répondant à la formulation suivante, en pourcentage massique, exprimée sous la forme d'oxydes : - entre 50% et 70% de ZrO2, comprenant éventuellement du HfO2 sous forme d'impuretés inévitables, - entre 20% et 40% de SiO2, - entre 1% et 10% d'au moins un oxyde choisi dans le groupe constitué par Pr6O11 et V2O5, - moins de 2,5% d'autres oxydes, - la somme desdits oxydes représentant au moins 98% de la masse dudit pigment, dans lequel plus de 70% en nombre des particules constituant ladite poudre ont une forme sensiblement polyédrique, dans lequel plus de 50% en nombre des particules constituant ladite poudre présentent une longueur inférieure ou égale à 1 micromètre. Pigment in the form of a powder of particles, having a zircon mass content greater than or equal to 80% based on the summed mass of the crystallized zircon and zirconia phases present in said pigment, said pigment having the following formulation as a percentage by mass, expressed in the form of oxides: between 50% and 70% of ZrO 2, optionally comprising HfO 2 in the form of unavoidable impurities, between 20% and 40% of SiO 2, between 1% and 10% % of at least one oxide selected from the group consisting of Pr6O11 and V2O5, - less than 2.5% of other oxides, - the sum of said oxides accounting for at least 98% of the mass of said pigment, in which more than 70 the number of particles constituting said powder has a substantially polyhedral shape, in which more than 50% by number of the particles constituting said powder have a length less than or equal to 1 micrometer.

COMMUNICATION DEVICE

Dispositif de communication par ondes hertziennes de fréquences comprises entre 800MHz à 3GHz comportant un capot céramique exposé, au moins en partie, à l'environnement extérieur du dispositif et traversé par au moins une partie desdites ondes lors de l'utilisation du dispositif, ce capot étant au moins en partie constitué en un produit fritté présentant une composition chimique telle que, en pourcentage massique et pour un total de 100% : - 32 % <= ZrO2 <= 95%, 1 < Y O +CeO +Sc O +MgO+CaO, - 0% <= CeO <= 26%, - 0% <= MgO <= 43%, - 0% <= CaO <= 37%, - 0%<= SiO <= 41%, - 0% <= Al O <= 55%, - 0% <= TiO <= 30%, - 0% <= oxydes de lanthanides excepté CeO <= 50%, - 0% <= SrO <= 24%, 0% <= composés SiAlON <= 50%, - autres composés <= 15%. Device for communication by radio waves of frequencies between 800 MHz to 3GHz comprising a ceramic cover exposed, at least in part, to the external environment of the device and traversed by at least a portion of said waves when using the device, this hood being at least partly made of a sintered product having a chemical composition such that, in mass% and for a total of 100%: - 32% <= ZrO2 <= 95%, 1 <YO + CeO + Sc O + MgO + CaO, - 0% <= CeO <= 26%, - 0% <= MgO <= 43%, - 0% <= CaO <= 37%, - 0% <= SiO <= 41%, - 0% < = Al O <= 55%, - 0% <= TiO <= 30%, - 0% <= oxides of lanthanides except CeO <= 50%, - 0% <= SrO <= 24%, 0% <= compounds SiAlON <= 50%, - other compounds <= 15%.

Hip joint prosthesis having a zirconia head and a ceramic cup

This invention relates to a biojoint prosthesis comprising: a) a prosthetic comprising a first component, such as a femural head, having an outer surface comprising at least 90 mol % zirconia, and b) a second component, such as an acetabular cup, having a surface comprising a ceramic such as alumina, shaped to receive the outer surface of the first component, wherein the outer surface of the first component is received on the surface of the second component, and wherein (i) at least a portion of the surface of the second component receiving the first component comprises a ceramic having a surface roughness of no more than 100 nm, and (ii) the outer surface of the first component has a surface roughness of no more than 100 nm. Maintaining the surface roughness Ra at each surface below 100 nm substantially prevents surface damage nucleation when the articulation is in the low force regime common to hip joint prosthesis articulating surfaces. To attain low wear rates, surfaces are made smooth. Controlling the surface roughness of each surface to less than 15 nm reduces wear even more significantly.

FILTERS COMPRISING OXYGEN BASED SIC MEMBRANES

Structure for filtering a gas and reducing nox

The invention relates to a structure (1) for filtering gases laden with particulates and with gaseous pollutants, said structure being of the honeycomb type and comprising a set of adjacent longitudinal channels (2, 3) having mutually parallel axes separated by porous filter walls (6). The structure is characterized in that: a first portion (6'') of the walls (6) of the channels, in a part situated at the downstream end (5) of the filter, is permeable to the gases being treated and has an open porosity of between 30 and 80%; and a second portion (6') of the walls of the channels, in a part situated at the upstream end (4) of the filter, has at least on the surface of the inlet channels (3) a porosity lower than that of the portion (6'') situated at the downstream end of the filter, whereby the less porous wall portion (6'), in the part situated at the upstream end of the filter, is covered with and/or incorporates a catalytic NOx-reduction system (8) or an SCR-type system.

Balls from molten ceramic material

Fused ceramic balls have compsn. (by wt.) 40-95% ZrO2 + HfO2; 0.1-25% total of 0.1-10% Y2O3 and/or 1-15% CeO2; and either 10-45% SiO2, when CeO2 is absent, or 0.5-45% SiO2 when CeO2 is present.

Colored sintered zirconia

Processo de fabricação de produtos porosos de subóxidos de titânio e produtos porosos

Processo de fabricação de produtos porosos constituídos essencialmente de subóxido(s) de titânio de formulação genérica TiOx, o valor de x estando compreendido entre 1,6 e 1,9, o referido processo compreendendo as etapas seguintes: a) mistura das matérias-primas compreendendo, pelo menos, uma fonte de dióxido de titânio, um agente redutor compreendendo carbono, b) conformação do produto, c) opcionalmente, notadamente quando os produtos orgânicos são utilizados durante a etapa a), tratamento térmico sob ar ou atmosfera oxidante, d) sinterização, por exemplo, a uma temperatura superior a 1150°C, mas não ultrapassando 1430°C, sob uma atmosfera neutra ou redutora, em que a fonte de dióxido de titânio é constituída de pelo menos 55% em peso de anatase. Produto susceptível de ser obtido por tal processo.

Porøst keramisk produkt af titanium-suboxider

Verfahren zur herstellung einer porísen struktur unter verwendung von porenbildenden mitteln auf siliziumbasis

Praseodymium zircon-oxide yellow pigment and composition for making same

The invention concerns a yellow pigment characterised in that it has the following chemical analysis, in wt. % on the basis of 52.6 to 71.7 % of ZrO2, 21.6 to 38.8 % of SiO2, 3 to 6.4 % of Pr6O11, and 0.3 to 2.2 % of Y2O3. The invention is useful for colouring ceramic materials.

Pigment jaune zircon-oxyde de praseodyme et composition pour sa fabrication

L'invention concerne un pigment jaune caractérisé en ce qu'il présente l'analyse chimique suivante, en % en poids sur la base des 52,6 à 71,7 % de ZrO2, 21,6 à 38,8 % SiO2, 3 à 6,4 % de Pr6O11, et O,3 à 2,2 % de Y2O3. Utilisation notamment pour la coloration de matières céramiques.

Reinigungsstruktur mit integriertem elektrochemischem katalysesystem

Filtre der omfatter oxygen-depleterede sic-membraner

Zircon-praseodymium oxide yellow pigment and composition for its preparation

Zircon-praseodymium oxide yellow pigment and composition for its preparation

Gelbes zirkon-praseodymoxid-pigment sowie zusammensetzung für seiner herstellung

Pigment jaune zircon-oxyde de praseodyme et composition pour sa fabrication

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Thermisch stabile isolierbauteile aus feuerfesten keramikfasern

Produits céramiques poreux de sous oxydes de titane

Kugeln aus geschmolzenen keramischen werkstoff