Abstract: The present application relates to a large-size, high-dielectric breakdown strength titanium oxide based dielectric ceramic material, a preparation method and application thereof. The composition of the titanium oxide based dielectric ceramic material comprises: a CaTiO3+b SrTiO3+c TiO2+d Al2TiO5+e SiO2, wherein a, b, c, d, and e are the mole percentage of each component, 15?a?35 mol %, 0?b?2 mol %, 30?c?84 mol %, 0.5?d?25 mol %, 0.5?e?15 mol %, and a+b+c+d+e=100 mol %.

Abstract: The present specification relates to a method for manufacturing an electrolyte membrane for a solid oxide fuel cell, an electrolyte membrane for a solid oxide fuel cell, a solid oxide fuel cell including the electrolyte membrane, and a fuel cell module including the solid oxide fuel cell.

Abstract: The present application discloses a sintered ceramic material having high fracture toughness and bending strength, which is obtained from an yttria-stabilized Zirconia powder, the powder composition for obtaining said material, sintered ceramic pieces and manufacturing process thereof. One of the solutions of the present invention discloses a sintered ceramic material which is obtained from an yttria-stabilized zirconia powder, comprising between 1.8 and 2.1 mol % yttria, wherein the sintered ceramic material has a percentage of tetragonal phase greater than 90% at room temperature, a grain size between 0.1 to 0.25 ?m, the bending strength is between 1150-2100 MPa, and simultaneously a toughness greater than 10 MPa·m1/2. This material may be applied in different sintered ceramic pieces, including pieces for the automotive sector, for diverse machinery, ornamental applications such as timepieces or pieces for biomedical applications, among others.

Abstract: Provided is a lead-free piezoelectric material having satisfactory and stable piezoelectric constant and mechanical quality factor in a wide practical use temperature range. The piezoelectric material includes a perovskite-type metal oxide represented by Formula (1): (Ba1?xCax)a(Ti1?yZry)O3 (wherein, 1.00?a?1.01, 0.125?x?0.300, and 0.041?y?0.074), Mn, and Mg. The content of Mn is 0.12 parts by weight or more and 0.40 parts by weight or less based on 100 parts by weight of the perovskite-type metal oxide on a metal basis. The content of Mg is 0.10 parts by weight or less (excluding 0 part by weight) based on 100 parts by weight of the perovskite-type metal oxide on a metal basis.

Abstract: The present invention provides a lead-free piezoelectric material having a high piezoelectric constant and a high mechanical quality factor in a wide operating temperature range. The piezoelectric material includes a perovskite-type metal oxide represented by Formula (1): (Ba1-xCax)a(Ti1-yZry)O3 (1.00?a?1.01, 0.125?x<0.155, and 0.041?y?0.074) as a main component. The metal oxide contains Mn in a content of 0.12 parts by weight or more and 0.40 parts by weight or less based on 100 parts by weight of the metal oxide on a metal basis.

Abstract: A ceramic powder contains a metal oxide represented by the following general formula (1). The ceramic powder has a single perovskite-type crystal phase. The ceramic powder is composed of particles having an average equivalent circular diameter in the range of 100 nm or more and less than 1000 nm and has a ratio c1/a1 in the range of 1.000?c1/a1?1.010, wherein c1 and a1 denote the c-axis length and a-axis length, respectively, of unit cells of the perovskite-type metal oxide, c1 being greater than or equal to a1. formula (1)(Ba1-xCax)?(Ti1-y-zZryMnz)O3(0.9900???1.0100, 0.125?x?0.300, 0.020?y?0.095, 0.003?z?0.016).

Abstract: A piezoelectric material that does not contain lead and has excellent piezoelectric constant and mechanical quality factor in a device driving temperature range (?30° C. to 50° C.) is provided. A piezoelectric material includes a main component containing a perovskite metal oxide represented by following general formula (1), and a first auxiliary component containing Mn, wherein an amount of the contained Mn is 0.002 moles or more and 0.015 moles or less relative to 1 mole of the metal oxide. (Ba1-yBiy)a(Ti1-x-zZrxFez)O3??(1) (where 0.010?x?0.060, 0.001?y?0.015, 0.001?z?0.015, 0.950?y/z?1.050, and 0.986?a?1.020).

Abstract: A method for producing a silicon-containing zirconia calcined body includes wet mixing a mixture to obtain a mixed slurry, with the mixture including a silicon-containing zirconia powder, a sodium carbonate powder, a tetraethoxysilane, and an adhesive; drying the mixed slurry to obtain a caked mass; grinding and sieving the caked mass to obtain a mixed powder; pressurizing and shaping the mixed powder to obtain a blank; and calcining the blank in an environment at 900-1200° C. to obtain a silicon-containing zirconia calcined body. The silicon-containing zirconia calcined body can be sintered at 1415-1450° C. into a silicon-containing zirconia sintered body, with a shrinkage ratio during sintering the silicon-containing zirconia calcined body into the silicon-containing zirconia sintered body being 22-31%.

Abstract: Provided is a lead-free piezoelectric ceramics having enhanced mechanical quality factor (Qm) and mechanical strength. The piezoelectric ceramics, includes at least a first crystal grain and a second crystal grain. The first crystal grain has an average equivalent circle diameter of 2 ?m or more and 30 ?m or less. The first crystal grain includes a perovskite-type metal oxide represented by the following general formula (1) as a main component, and the second crystal grain includes a perovskite-type metal oxide represented by the following general formula (2) as a main component: (1) xBaTiO3-yCaTiO3-zCaZrO3; and (2) x?BaTiO3-y?CaTiO3-z?CaZrO3, provided that x, y, z, x?, y?, and z? satisfy x+y+z=1, x?+y?+z?=1, 0?x??0.15, 0.85?y??1, 0?z?0.05, x>x?, 0<y<y?, and z>0.

Abstract: This invention provides a family of functionalized polymers capable of forming membranes having exceptional OH? ionic conductivity as well as advantageous mechanical properties. The invention also provides membranes including the provided polymers and AEMFC/HEMFC fuel cells including such membranes. In a preferred embodiment, preferred function groups include a quaternary phosphonium, and in a more preferred embodiment the provided polymer is (tris(2,4,6-trimethoxyphenyl) phosphine)3 functionalized phosphonium polysulfone hydroxide.

Abstract: A family of functionalized polymers is provided capable of forming membranes having exceptional OH? ionic conductivity as well as advantageous mechanical properties, which may be applied to membranes including such polymers for use in, e.g., AEMFC/HEMFC fuel cells. Preferred functional groups include a quaternary phosphonium, and the polymer may specifically be (tris(2,4,6-trimethoxyphenyl) phosphine)3 functionalized phosphonium polysulfone hydroxide, ECL-PVBC-QPOH, or QPOH based on any of the commercial polumers including polycarbonate (PC), poly(2,6-dimethyl-1,4-phenylene oxide) (PPO), polyetherimine (PEI), poly(ether sulfone) (PES), poly(phenylene sulfoxide) PPS, poly(ether ether ketone) (PEEK), or polybenzimidazole (PBI), polyvinyl chloride (PVC). An ionomer membrane may include polysulfone based TPQPOH, ECL-PVBC-QPOH, and/or PPO.

Abstract: The invention is a solution impregnation and drying treatment that imparts a high temperature binder into an already formed porous green body composed of particulate batch material. The batch material includes inorganic compounds and binder. The result is reduced sag and distortion and the same or increased strength when the porous body is later fused during sintering/firing.

Abstract: A method for producing a superconductive wire, whereby an elongated intermediate element is formed out of an initial element in a deformation step and whereby the superconductive filaments are formed by a final reaction heat treatment, is characterized in that prior to the final reaction heat treatment the filaments in the intermediate element are densified in one or more high pressure densification steps following up the deformation step, said densification steps comprising a simultaneous action of at least four hard surfaces perpendicular to the axis of the elongated intermediate element, building up high pressure P?100 MPa on a part of the intermediate element having an axial length L. This leads to a substantial increase of the critical current density Jc, whereby the anisotropy factor ? is be almost not affected thus enabling production of almost isotropic wires or tapes.

Abstract: Methods of forming composite materials include coating particles of titanium dioxide with a substance including boron (e.g., boron carbide) and a substance including carbon, and reacting the titanium dioxide with the substance including boron and the substance including carbon to form titanium diboride. The methods may be used to form ceramic composite bodies and materials, such as, for example, a ceramic composite body or material including silicon carbide and titanium diboride. Such bodies and materials may be used as armor bodies and armor materials. Such methods may include forming a green body and sintering the green body to a desirable final density. Green bodies formed in accordance with such methods may include particles comprising titanium dioxide and a coating at least partially covering exterior surfaces thereof, the coating comprising a substance including boron (e.g., boron carbide) and a substance including carbon.

Abstract: A translucent polycrystalline sintered body is mainly composed of an alumina, is suitable for the manufacture of an arc tube for a high-intensity discharge lamp, and has an average grain diameter of 35 to 70 ?m, preferably 50 to 60 ?m. In a case where the sintered body is in a 0.5-mm-thick flat plate shape, the in-line transmittance of the sintered body is 30% or more, preferably 50% or more. In this case, the ratio between maximum and minimum in-line transmittance values is 2:1 to 1:1 in the visible region of 360 to 830 nm. The bending strength of the sintered body is 250 MPa or more, preferably 300 MPa or more.

Abstract: A porous device for optical and electronic applications comprises a single crystal substrate and a porous single crystal structure epitaxially disposed on the substrate, where the porous single crystal structure includes a three-dimensional arrangement of pores. The three-dimensional arrangement may also be a periodic arrangement. A method of fabricating such a device includes forming a scaffold comprising interconnected elements on a single crystal substrate, where the interconnected elements are separated by voids. A first material is grown epitaxially on the substrate and into the voids. The scaffold is then removed to obtain a porous single crystal structure epitaxially disposed on the substrate, where the single crystal structure comprises the first material and includes pores defined by the interconnected elements of the scaffold.

Abstract: A method and product made by using a polymeric ceramic precursor to synthesize dense, crack-free bulk ceramics in a technique using a sacrificial mold provides a ceramic structure for many technical, medical and industrial applications. The novel process uses an open cell material as a sacrificial mold to shape a ceramic precursor during curing. The cured ceramic green body can be machined and shaped to form the desired ceramic structure prior to final pyrolysis. The open cell material forms gas release paths to release large amount of gases generated during the pyrolysis of the cured ceramic precursor. After pyrolysis, an intact, dense, crack-free ceramic structure with high purity, strength and durability is obtained. Uses of the present invention include, but are not limited to, bulk ceramic parts, ceramic crucibles, a replacement material in some applications involving glass, silicon carbides, silicon nitrides, hafnium carbide and the like.

Abstract: A straightforward and scalable solid-state synthesis at 975° C. used to generate cathode materials in the system Li(3+x)3Ni(1-x-y)CoyMn2x/3O2 {a combination of LiNiO2, Li2MnO3, and LiCoO2 as (1-x-y)LiNiO2.xLi2MnO3.yLiCoO2} is described. Coatings for improving the characteristics of the cathode material are also described. A ternary composition diagram was used to select sample points, and compositions for testing were initially chosen in an arrangement conducive to mathematical modeling. X-ray diffraction (XRD) characterization showed the formation of an ?-NaFeO2 structure, except in the region of compositions close to LiNiO2. Electrochemical testing revealed a wide range of electrochemical capacities with the highest capacities found in a region of high Li2MnO3 content. The highest capacity composition identified was Li1.222Mn0.444Ni0.167Co0.167O2 with a maximum initial discharge capacity of in the voltage range 4.6-2.0 V.

Abstract: A process for producing an anisotropic magnetic material includes: preparing a feebly magnetic material capable of transforming into a magnetic material by a prescribed reaction, orienting the feebly magnetic material by imparting an external field to the feebly magnetic material, and transforming the oriented feebly magnetic material to a magnetic substance by the prescribed reaction.

Abstract: Method for introduction of filling materials into porous bodies in which the filling materials in liquid form are brought into contact with the porous bodies and are distributed from at least one site within the porous body in this porous body.

Abstract: A method of sintering a ZrB2—SiC composite body at ambient pressures, including blending a first predetermined amount of ZrB2 powder with a second predetermined amount of SiC powder, wherein both powders are characterized by the presence of surface oxide impurities. Next the blended powders are mixed to yield a substantially homogeneous powder mixture and a portion of the substantially homogeneous powder mixture is formed into a green body. The body is fired to a first temperature, wherein substantially all surface oxide impurities are reduced and/or volatilized to substantially eliminate oxides from the green body, and the body is heated to a second temperature and sintered to yield a composite body of at least about 99 percent theoretical density and characterized by SiC whisker-like inclusions distributed substantially evenly in a ZrB2 matrix.

Abstract: Synthetic sintered YPO4 composite materials comprising excess amount of Y2O3 in the composition and process for making such materials. The Y2O3-modified sintered YPO4 composite material exhibits improved mechanical properties compared to stoichiometric YPO4 materials. The modified YPO4 materials can be used to produce different components used in the glass-making process such as, for example, an isopipe.

Abstract: There is disclosed a pre-sintering process for reducing non-uniformities in the density of a sintered material comprising (a) providing a mixture of (i) a first sinterable material containing a contaminant the presence of which during sintering of the first sinterable material results in a higher vapor pressure than would occur during sintering of pure first sinterable material and (ii) a second material having a higher affinity for the contaminant than does the first sinterable material; and (b) heating the mixture at a temperature and for a time sufficient to allow the second material to at least partly mitigate the propensity of the contaminant to raise the vapor pressure during the sintering of the first sinterable material. Other embodiments are also disclosed.

Abstract: An insulating target material for obtaining a conductive complex oxide film represented by a general formula ABO3, the insulating target material including an oxide of an element A, an oxide of an element B, and at least one of an Si compound and a Ge compound.

Abstract: A boron carbide based sintered body having a four-point flexural strength of at least 400 MPa and a fracture toughness of at least 2.8 MPa·m1/2, which has the following two preferred embodiments. (1) A boron carbide-titanium diboride sintered body obtained by sintering a mixed powder of a B4C powder, a TiO2 powder and a C powder while reacting them under a pressurized condition and comprising from 95 to 70 mol % of boron carbide and from 5 to 30 mol % of titanium diboride, wherein the boron carbide has a maximum particle diameter of at most 5 ?m. (2) A boron carbide-chromium diboride sintered body containing from 10 to 25 mol % of CrB2 in B4C, wherein the sintered body has a relative density of at least 90%, boron carbide particles in the sintered body have a maximum particle diameter of at most 100 ?m, and the abundance ratio (area ratio) of boron carbide particles of from 10 to 100 ?m to boron carbide particles having a particle diameter of at most 5 ?m, is from 0.02 to 0.6.

Abstract: The present invention relates to a process for the preparation of a silicate comprising at least silicon and oxygen, comprising (1) mixing of silicon dioxide and/or of a silicon dioxide precursor with an aqueous solution comprising at least one tetraalkylammonium compound comprising R1R2R3R4N+ and at least one base, wherein R1 and R2 are methyl and both R3 and R4 are n-propyl; (2) heating of the colloidal solution obtained according to (1) to a temperature in the range of from greater than the boiling point of the colloidal solution under the chosen pressure to 180° C. at atmospheric pressure to give a suspension comprising at least one silicate, wherein the silicate comprising at least silicon and oxygen is added as a crystallization auxiliary in (1).

Abstract: Clutch linings comprising fiber-reinforced ceramic materials which contain short carbon fibers and whose matrix has a mass fraction of at least 40% of silicon carbide, process for producing them and their use in clutch systems, in particular for motor vehicles.

Abstract: Ceramic composite materials have unidirectional alignment of the reinforcing fibers. The ratio of the volume of the fiber strands of the reinforcing fibers to the volume of the matrix is at least 0.5. A process for their production involves initially coating the fiber strands or rovings of the reinforcing fibers with a sacrificial polymer. The coated fiber strands are processed with binder resins into unidirectionally reinforced CFK molded parts. The formed CFK bodies are carbonized to form CFC bodies. The CFC bodies are then silicized with liquid silicon. The liquid silicon diffuses into the pores formed in the CFC body and combines there at least partially with the carbon to form silicon carbide. The sacrificial polymer is pyrolized. The ceramic composite materials also can be used in fiber-reinforced ceramic structural parts.

Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1?xRx)O.n[(Fe1?yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01?x?0.4, [x/(2.6n)]?y?[x/(1.6n)], and 5?n?6, and substantially having a magnetoplumbite-type crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.

Abstract: An oxide magnetic material comprising main constituents including Fe2O3, ZnO, CuO and NiO. Y2O3 of 0.003 to 0.021 wt % and-ZrO2 of 0.06 to 0.37 wt % are included in main constituents with respect to all amounts. It is also preferable that Si of 0.010 to 0.0112 wt % is included in main constituents with respect to all amounts. Further, it is also preferable that Y2O3 of 0.001 to 0.011 wt % , ZrO2 of 0.031 to 0.194 wt %, and Si of 0.010 to 0.056 wt % are included in main constituents with respect to all amounts.

Abstract: Nanoscale corundum powders are obtained by first producing an Al2O3 precursor by adding seed crystals to an aqueous solution of an aluminium compound and adding a base and then converting the Al2O3 precursor into corundum by calcination at a high temperature. Before the calcination, the salts that are present in addition to the Al2O3 precursor are separated off. The resulting product is calcined at temperatures of 700 to 975° C. and any fines that may be present are removed. The resulting corundum powders can be sintered at temperatures of ?1200° C. to produce compacts or components of multiple layer systems.

Abstract: A method for manufacturing an electrostatic chuck is disclosed wherein a sintered ceramic body having a dielectric layer made from Alumina (Al2O2) and Titanium Nitride (TiN) having a specific range of particle size is heat treated in an oxygen-rich environment in order to produce a uniform dielectric layer having no pores or micro-cracks.

Abstract: A method of making an oxide superconductor article includes converting an oxide superconducting precursor into an oxide superconductor by thermo-mechanical processing using intermediate rolling deformation and heat treatment (including liquid-phase sintering and low temperature baking) and applying an additional heat treatment after the material is fully processed (including optional liquid-phase sintering and low temperature baking) to decompose any secondary phase remaining at the grain boundaries and to promote diffusion of the secondary phase into the oxide grain, where they form 2223 phase. The material has a better superconducting grain connectivity and improved superconducting transport property.

Abstract: Fiber-reinforced ceramic composites contain bundles, tows or hanks of long fibers, wherein the long fiber bundles, tows or hanks are completely surrounded by a short fiber-reinforced matrix, with the long and short fibers having, independently of one another, a mean diameter of from 4 to 12 &mgr;m and the long fibers having a mean length of at least 50 mm and the short fibers having a mean length of not more than 40 mm, a process for producing them and their use for producing clutch disks or brake disks.

Abstract: A dielectric ceramic article precursor and a process for preparing a dielectric ceramic article are presented. The ceramic article precursor comprises a crystalline aluminosilicate zeolite or an amorphous aluminosilicate, a zinc oxide additive and a glass phase. The ceramic article precursor can optionally contain at least one forming aid selected from binders, plasticizers and surfactants. The process for preparing a dielectric ceramic article involves forming a mixture from the above components into a shaped article such as a tape and then calcining the shaped article at a temperature of about 700° C. to about 1000° C. for a time of about 0.5 to about 24 hours.

Abstract: A producing method of a porous Si3N4 having high porosity and formed of Si3N4 particles having a high aspect ratio includes the following steps. A compound of a rare earth element as a first sintering agent is mixed in an amount of 7.5-45 parts by mass, in terms of an oxide of the element, with respect to 100 parts by mass of Si powder to obtain mixed powder. A binder is added to the mixed powder, which is then molded into a molded body. The molded body is heated in a nitrogen atmosphere to 300-500° C. to remove the binder. The binder-removed body is heated in a nitrogen atmosphere to 1350-1500° C. for nitriding. The nitrided body is then sintered at 1750-1900° C. at a nitrogen pressure of 0.1-1 atmosphere.

Abstract: The present invention relates to a silicon carbide-boron nitride composite material, which synthesised according to an in-situ chemical reaction between silicon nitride, boron carbide and carbon, and which contains fine boron nitride particles dispersed in a silicon carbide matrix, wherein aforementioned composite material is obtained by molding a powder mixture containing each of the components required in the in-situ reaction and sintering the mixture.

Abstract: A method for reaction forming refractory metal carbides. The method involves the fabrication of a glassy carbon preform by casting an organic, resin-based liquid mixture into a mold and subsequently heat treating it in two steps, which cures and pyrolizes the resin resulting in a porous carbon preform. By varying the amounts of the constituents in the organic, resin-based liquid mixture, control over the density of the carbon preform is obtained. Control of the density and microstructure of the carbon preform allows for determination of the microstructure and properties of the refractory metal carbide material produced. The glassy carbon preform is placed on a bed of refractory metal or refractory metal—silicon alloy. The pieces are heated above the melting point of the metal or alloy. The molten metal wicks inside the porous carbon preform and reacts, forming the refractory metal carbide or refractory metal carbide plus a minor secondary phase.

Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1−xRx)O.n[(Fe1−yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01≦x≦0.4, [x/(2.6n)]≦y≦[x/(1.6n)], and 5≦n≦6, and substantially having a magnetoplumbite crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.

Abstract: A process form producing ceramic composites comprising metal carbides, which comprises the steps production of a porous carbon-containing intermediate body, infiltration of the intermediate body with the melt of a carbon-forming metal, reaction of at least part of the carbon of the intermediate body with the carbide-forming metal to form a metal carbide, with at least part of the carbide-formed metal being supplied via at least one wick made of porous carbon material having pore channels and the wick being produced by carbonization of wood materials or of essentially unidirectionally reinforced CFRP, such wicks and their use in the abovementioned process

Abstract: A method for producing electroceramic materials of high sintered density from hydroxide and/or oxalate precursors is disclosed. In this method the precursor(s) are compacted to form a preform, thermally treated, recompacted and then sintered to form finished products.

Abstract: Nanoscale corundum powders are obtained by first producing an Al2O3 precursor by adding seed crystals to an aqueous solution of an aluminium compound and adding a base and then converting the Al2O3 precursor into corundum by calcination at a high temperature. Before the calcination, the salts that are present in addition to the Al2O3 precursor are separated off. The resulting product is calcined at temperatures of 700 to 975° C. and any fines that may be present are removed. The resulting corundum powders can be sintered at temperatures of ≦1200° C. to produce compacts or components of multiple layer systems.

Abstract: A process for forming a silicon carbide structure includes molding by compression a mixture of a silicon precursor powder and a cross-linking thermoset resin to form a rigid structure, carbonizing the rigid structure, and forming a silicon carbide structure by heating the carbonized rigid structure at a temperature sufficient to allow carbon and silicon in the structure to react to form silicon carbide.

Abstract: A silicon carbide honeycomb body is made by shaping a plasticizable raw material batch mixture containing powdered silicon metal, a water soluble crosslinking thermoset resin, a powdered silicon-containing filler, a water soluble thermoplastic binder, and water into a green honeycomb body, and thereafter drying, curing and sintering the green body at a temperature sufficient to convert the green body to a porous silicon carbide sintered body.

Abstract: Methods of making metal oxide articles, preferably iron oxide articles, and articles thereby produced. The method comprises the steps of slightly pressing powder to a compact, the powder consisting essentially of a first oxide of the metal; and subjecting the compact to a heat treatment that causes the powder to sinter into a unitary body and results in the transformation of at least a portion of the first oxide to a second oxide by oxidation or deoxidation during the heat treatment. In disclosed embodiments, the heat treatment is conducted either in air at atmospheric pressure or at a subatmospheric pressure. The method optionally includes more heating/cooling steps resulting in additional oxidation/deoxidation cycles. Sintered iron oxide articles of the invention have high mechanical strengths and interconnected pore structures, providing for efficient filtering of liquids and gases.

Abstract: The invention is a method of producing a ceramics material comprising the steps of: preparing a raw powder in which alumina particles having an average particle diameter of 0.1-1.0 &mgr;are doped with at least magnesia of 0.01-1 weight % and a solution containing yttrium of 0.1-15 weight % in yttria; molding said raw powder and calcining a molding thus created; and heating the calcined molding in an atmosphere containing a hydrogen gas to create YAG which is leached to the surface to deposit YAG on the surface and sintering the molding.

Abstract: Methods of making metal oxide articles, preferably iron oxide articles, and articles thereby produced. The method comprises the steps of slightly pressing powder to a compact, the powder consisting essentially of a first oxide of the metal; and subjecting the compact to a heat treatment that causes the powder to sinter into a unitary body and results in the transformation of at least a portion of the first oxide to a second oxide by oxidation or deoxidation during the heat treatment. In disclosed embodiments, the heat treatment is conducted either in air at atmospheric pressure or at a subatmospheric pressure. The method optionally includes more heating/cooling steps resulting in additional oxidation/deoxidation cycles. Sintered iron oxide articles of the invention have high mechanical strengths and interconnected pore structures, providing for efficient filtering of liquids and gases.

Abstract: The present invention is intended to provide piezoelectric ceramic materials having far better strain characteristics than that of conventional piezoelectric ceramics, as well as a novel method for producing such piezoelectric ceramics, and the present invention involves solid solution piezoelectric ceramics primarily comprising the complex perovskite compound Pb(Ni⅓Nb⅔)O3, the simple perovskite compound PbTiO3, and PbZrO3, wherein the aforementioned ceramics primarily comprise compositions within a triangle in which the compositional vertices are (X=52, Y=34, Z=14), (X=49, Y=37, Z=14), and (X=49, Y=34, Z=17), where Pb(Ni⅓Nb⅔)O3 is X mol %, PbTiO3 is Y mol %, and PbZrO3 is Z mol % (X+Y+Z=100) among the triangular coordinates in the phase diagram in which the vertices are Pb(Ni⅓Nb⅔) O3, PbTiO3, and PbZrO3, as well as a method for producing such solid solution ceramics.

Abstract: The present invention provides a process for preparing a raw material powder for producing a sintered body of aluminum titanate comprising: pulverizing a mixture containing: (1) 100 parts by weight of aluminum titanate crystals pulverized until a maximum grain size of 30 to 50 &mgr;m is attained; and (2) 2 to 6 parts by weight of spinel crystals obtained by heating a mixture containing MgO and Al2O3 at 1250° C. to 1290° a molar ratio of MgO to Al2O3 being 1:0.95 to 1:1.05, said pulverizing being conducted by wet grinding process with a ball mill or cylinder mill.

Abstract: Disclosed is a sol-gel process for making high-density monolithic alpha-alumina articles. Cracking problems caused by shrinkage of the gel during the drying and firing stages are minimized by controlling the temperature and humidity during the drying process and by using molds formed of prescribed polymeric materials, preliminarily coated with a silicone release agent. The process of the invention provides porous alpha-alumina articles having a controlled microstructure and a controlled pore size distribution, which are beneficial features when the material is used in practical applications, e.g., as substrates for gas sensors.