Aluminum Compound (e.g., Clay, Aluminium Oxide, Etc.) Patents (Class 501/127)
-
Patent number: 5698485Abstract: A process for producing a ceramic having a microstructured surface with a surface profile depth of less than 1 micron, measured by the atomic force microscopy, comprising preparing a polymeric precursor material, shaping the precursor material into a structured mold insert of an inherently stable mold insert material having a structured surface geometry corresponding with the microstructured surface of the ceramic to form a shaped precursor material, the shaped precursor material being rendered infusible by chemical crosslinking, and wherein the inherently stable mold insert material is selected from materials having sufficient strength for structuring and high molding accuracy, and pyrolyzing the shaped precursor material, whereby the ceramic having the microstructured surface is obtained.Type: GrantFiled: January 22, 1996Date of Patent: December 16, 1997Assignees: Hoechst Aktiengesellschaft, Institut Fuer Mikrotechnik GmbHInventors: Martin Bruck, Tilo Vaahs, Wolfgang Bocker, Wolfgang Ehrfeld, Manfred Lacher, Ludwig Giebel
-
Patent number: 5691259Abstract: A shaped ceramic article capable of being cut manually into selected sizes and process is based on a mixture of high-temperature resistant ceramic fibers and fibers which soften at temperatures below 2000.degree. F., particles of a ceramic material stable to temperatures exceeding 2000.degree. F., particles of a ceramic material which sinter at temperatures below 2000.degree. F., and a binder which provides green strength to shapes formed by vacuum formation from a slurry. The vacuum formed shape is dried at about 400.degree. F., thereby dried to form a shape which is preferably dipped in colloidal alumina or silica and dried again. The shape is sinterable by contact with flowing molten metal or by being sujected to radiant heat to form a hardened shape-stable ceramic form.Type: GrantFiled: November 8, 1996Date of Patent: November 25, 1997Assignee: Fiber Ceramics, Inc.Inventors: Clifford E. Couture, Paul A. Schumacher, Orville C. Clemmons
-
Patent number: 5688730Abstract: Gamma-aluminum oxynitride ground powders, white in color and well suited for conversion into optically transparent ceramic shaped articles, 100% of the particles of which being less than 10 .mu.m in size and exhibiting a transmittance of at least 8%, are prepared by grinding particulate gamma-aluminum oxynitride agglomerates having a porosity of greater than 75%, such agglomerates themselves being produced by interreacting dry powdery admixture of aluminum nitride, alpha-alumina, and an alumina of high specific surface area or precursor thereof.Type: GrantFiled: July 19, 1996Date of Patent: November 18, 1997Assignee: Elf Atochem S.A.Inventors: Roland Bachelard, Jean-Pierre Disson, Bruno Morlhon
-
Patent number: 5686366Abstract: A platelet .alpha.-Al.sub.2 O.sub.3 based ceramic composite consists of Al.sub.2 O.sub.3 powder, promoters and controllers. The composite is prepared by mixing aluminum oxide powder with promoters and controllers. The mixture is shaped and sintered to form an object. In one embodiment of the invention, the promoters are either salts or oxides of alkaline metals and alkaline earth metals. The salts are oxidized during sintering.Type: GrantFiled: August 3, 1994Date of Patent: November 11, 1997Assignee: Mitsubishi Materials CorporationInventors: Takashi Koyama, Koichi Niihara
-
Patent number: 5676745Abstract: Composites in the form of a three-dimensional framework or skeleton of ceic particles are formed by a low cost, low temperature sintering process which decomposes a pre-ceramic inorganic or organic precursor. Upon heating, preferably in air, the precursor decomposes to form a ceramic phase in the form of necks between the individual ceramic particles. The properties of the resulting porous ceramic bodies can be modified, such as toughened by impregnation with monomers, oligomers or polymers which are polymerized or cured in situ. Such composites find use as cosmetic products or protheses for humans and animals, such as dental restoratives and bone implants. Methods of fabrication are disclosed which include the use of a pre-ceramic polymer as a binder for the ceramic particles which forms the necks of material between the individual ceramic particles upon firing.Type: GrantFiled: June 7, 1995Date of Patent: October 14, 1997Assignee: The United States of America, as represented by the Secretary of CommerceInventors: John Robert Kelly, Joseph M. Antonucci
-
Patent number: 5672554Abstract: An alumina composition, an alumina molded article, prepared from the alumina composition, an alumina ceramic prepared by sintering the alumina molded article, and a process for producing the ceramic; the alumina composition comprising .alpha.-alumina particles having a ratio of the shortest diameter to the longest diameter of from 0.3 to 1; and a size distribution of not more than 5, as expressed in terms of a D.sub.90 /D.sub.10 ratio, wherein D.sub.10 and D.sub.90 represent a cumulative 10% diameter and a cumulative 90% diameter, respectively, of a cumulative distribution depicted from the small diameter side, or comprising .alpha.-alumina particles having a polyhedral shape; a D/H ratio of from 0.5 to 3.0, wherein D represents a maximum particle diameter parallel to a hexagonal lattice plane of a hexagonal close-packed lattice of .alpha.-alumina, and H represents a particle diameter perpendicular to the lattice plane; and a size distribution of not more than 5, as expressed in terms of a D.sub.90 /D.sub.Type: GrantFiled: May 28, 1996Date of Patent: September 30, 1997Assignee: Sumitomo Chemical Company, LimitedInventors: Masahide Mohri, Norio Matsuda, Shinichiro Tanaka, Yoshio Uchida
-
Patent number: 5670253Abstract: A composite ceramic wafer including a beta silicon carbide layer. The composite ceramic wafer is useful for making thin film magnetic heads.Type: GrantFiled: December 20, 1995Date of Patent: September 23, 1997Assignee: Minnesota Mining and Manufacturing CompanyInventors: Raymond C. Chiu, Robert G. Smith, Billy Lee Weaver
-
Patent number: 5665127Abstract: Microcrystalline bodies based on .alpha.-Al.sub.2 O.sub.3 are made by drying sub-micron powders, press compacting and shock sintering at an intermediate sinter temperature range of 1,300.degree. to 1,550.degree. C., i.e. bringing the compact up to such range in under 60 seconds, preferably under 10.Type: GrantFiled: January 24, 1996Date of Patent: September 9, 1997Assignee: H.C. Starck GmbH & Co. KGInventors: Paul Moltgen, Pirmin Wilhelm, Josef Schmoll
-
Patent number: 5658838Abstract: The present invention relates to novel alumina-based ceramic composition containing a compound capable of forming a spinel-type aluminate phase detectable by x-ray diffraction, the composition having particular advantage for use as a water faucet seal.Type: GrantFiled: March 15, 1996Date of Patent: August 19, 1997Assignee: Norton Desmarquest Fine CeramicsInventor: Ridha Trabelsi
-
Patent number: 5656562Abstract: A method for improving the properties of ceramic green bodies is provided. In particular, ceramic green bodies having improved green strength are provided. Incorporating certain acid-containing polymers as binders at a level of at least about 1 to about 15, preferably at least about 3 to about 10 percent by weight based on the weight of ceramic particles improves the green strength of the resulting ceramic green bodies.Type: GrantFiled: June 5, 1996Date of Patent: August 12, 1997Inventor: Xianliang Wu
-
Patent number: 5652189Abstract: A ceramic composition for sintering into sliding parts contains:at least 90% by weight alumina,1.7% by weight to 2% by weight Mn.sub.3 O.sub.4,0.8% by weight to 1% by weight TiO.sub.2,0.5% by weight to 1.5% by weight SiO.sub.2,0.6% by weight to 1.2% by weight CoO,not more than 1% by weight MgO,not more than 0.4% by weight Fe.sub.2 O.sub.3,the remainder, up to 0.5% in total, comprising impurities.After sintering, this composition produces sliding parts containing manganese aluminate and/or cobalt aluminate phases.Type: GrantFiled: June 7, 1995Date of Patent: July 29, 1997Assignee: Norton Desmarquest Fine CeramicsInventor: Ridha Trabelsi
-
Patent number: 5650121Abstract: The disclosed invention provides a method of forming refractory linings for maintaining refractory linings against attack by corrosive materials such as those present in steel manufacture. The method entails spraying an aqueous mixture of a refractory composition that includes at least one refractory material onto the working surface of a refractory lining. Spraying is performed to provide one or more layers of the refractory composition on the refractory lining after each exposure of the lining to corrosive materials such as those incurred in steel manufacture.Type: GrantFiled: June 6, 1995Date of Patent: July 22, 1997Assignee: Minerals Technologies, Inc.Inventors: Julie Annette Dody, Charles R. Rumpeltin, Jr.
-
Patent number: 5648303Abstract: Non-magnetic ceramics for recording/reproducing heads comprising an alumina and any one of a compound selected from silicon carbide, boron carbide, zirconium carbide, titanium oxide, aluminum boride or zirconium boride, said ceramics having a Young's modulus of not smaller than 370 Gpa and a surface coarseness Ra after milling of not larger than 100 nm, and a method of producing the same.Type: GrantFiled: February 27, 1995Date of Patent: July 15, 1997Assignee: Kyocera CorporationInventor: Tsunehiko Nakamura
-
Patent number: 5641720Abstract: A corundum porcelain composition containing from 60 to 94% by weight of a component A and from 6 to 40% by weight of a component B, wherein component A contains from 0 to 70% by weight of alumina, from 20 to 70% by weight of clay material, from 10 to 50% by weight of glass formers and from 0 to 30% by weight of quartz, and component B comprises comminuted broken porcelain, the chemical composition of the mixture of the components A and B comprises from 20 to 75% by weight of SiO.sub.2, from 15 to 80% by weight of Al.sub.2 O.sub.3 and from 2 to 10% by weight of flux selected from the group consisting of K.sub.2 O, Na.sub.2 O, FeO, MgO, CaO, Li.sub.2 O; BaO, SrO, ZnO and fluoride, and the comminuted broken porcelain has a mean particle size between 25 and 800 .mu.m, useful, for example, in sintered bodies, such as insulators.Type: GrantFiled: November 29, 1995Date of Patent: June 24, 1997Assignee: Hoechst CeramTec AktiengesellschaftInventor: Gunter Fassbinder
-
Patent number: 5639704Abstract: The present invention relates to ceramics and a method for making ceramics having very little dimensional change after sintering and high dimensional accuracies, so that the characteristics of inorganic functional material are fully maintained and utilized. The ceramics of the present invention comprise grains of inorganic functional material and grains of complex oxide. The pores existing between said grains of inorganic functional material are filled with said grains of complex oxide produced by a sintering reaction between an oxidized metal and an inorganic compound.Type: GrantFiled: February 7, 1995Date of Patent: June 17, 1997Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Tsutomu Inuzuka, Shinji Harada, Yuji Mido, Tadashi Tojyo, Satoshi Tomioka
-
Patent number: 5637543Abstract: A ceramic composition for thermistor exhibiting stable resistance values over a wide temperature range and capable of being used for a prolonged time. The composition is represented by (M.sup.1 M.sup.2 O.sub.3).sub.1-x .multidot.(M.sup.1 AlO.sub.3).sub.x, wherein M.sup.1 is an element selected from the elements of the group 3A excluding La and M.sup.2 is an element of the groups 4A, 5A, 6A, 7A and 8, and wherein the mixing ratio between an electrically conductive substance stable at elevated temperatures and an insulating substance stable at elevated temperatures, may be adjusted. A thermistor formed of the composition is superior in high-temperature stability and can be used over a broad temperature range because its resistance value can be selected to an optimum value.Type: GrantFiled: December 18, 1995Date of Patent: June 10, 1997Assignee: NGK Spark Plug Co., Ltd.Inventors: Masaki Iwaya, Kyohei Hayashi, Hiroshi Matsuzaki, Yoshirou Suematsu
-
Patent number: 5633084Abstract: Fused alumina particles are covered with a coating of aluminum titanate which is formed by applying a Ti-containing compound to the surface of the fused alumina particles and firing the same to cause a reaction between the Ti-containing compound and the alumina.Type: GrantFiled: April 28, 1994Date of Patent: May 27, 1997Assignee: Showa Denko K.K.Inventors: Tadashi Hiraiwa, Fumiyoshi Ono
-
Patent number: 5627116Abstract: A sintered, translucent ceramic article comprises alpha alumina and up to 0.050 wgt. percent magnesia and between 0.001 to 0.100 wgt. percent lutetium oxide. In a preferred embodiment, the lutetium oxide is at 0.050 wgt. percent and in a second preferred embodiment half the lutetium oxide is replaced by yttrium oxide. A method of making a translucent ceramic article comprises the steps of: forming an aqueous slurry to yield one of the composition described above; adding nitric acid to adjust the pH to 4.6; adding an aqueous binder and plasticizer in the amount of 2.5 solids wgt. percent; spray-drying the slurry; forming an article by wet-bag isopressing; prefiring said article in air at about 1325.degree. C. for about 2 hours; and sintering said air-fired article in hydrogen for about 3 hours at 1800.degree. C.Type: GrantFiled: September 24, 1996Date of Patent: May 6, 1997Assignee: Osram Sylvania Inc.Inventor: Karlene J. Zuk
-
Patent number: 5625256Abstract: A ceramic discharge vessel (6) for a high-pressure discharge lamp (1) made from a sintered body of optically translucent polycrystalline alumina ceramic which is doped with only 100-800 ppm MgO, only 200-1200 ppm ZrO.sub.2 and only 10-300 ppm Y.sub.2 O.sub.3 (by weight). This improves the loading capacity and operating characteristics of the vessel and of the lamp.Type: GrantFiled: November 29, 1994Date of Patent: April 29, 1997Assignees: Patent-Treuhand-Gesellschaft F. Elektrische Gluehlampen mbH, NGK Insulators, Ltd.Inventors: Rita Tiedt, Helmut Weske, Koichiro Maekawa, Junichi Doi
-
Patent number: 5618762Abstract: An antibacterial ceramic contains an antibacterial material produced by loading an antibacterial metal such as silver on a calcium ceramic carrier and an inorganic material such as cordierite, and has a bulk density of 0.6-1.2 g/cm.sup.3. An antibacterial ceramic filter contains an antibacterial material produced by loading an antibacterial metal such as silver on a calcium ceramic carrier, an aggregate such as mullite, and a binder such as frit, and has a porosity of 20% or more. The light-weight antibacterial ceramic is suitably applicable to a roof garden or the like. The antibacterial ceramic filter can remove and extirpate various bacteria and suspensions.Type: GrantFiled: May 11, 1995Date of Patent: April 8, 1997Assignees: NGK Insulators, Ltd., NGK Adrec Co. Ltd., Sangi Co. Ltd.Inventors: Hiroshi Shirakawa, Osamu Yamakawa, Hiroaki Nihonmatsu, Kiminori Atsumi
-
Patent number: 5616526Abstract: There is now provided a ceramic material comprising of alumina, 10-50% by volume, preferably 20-35% by volume, silicon carbide whiskers, 1-25% by volume, preferably 5-20% by volume, most preferably 7-15% by volume, zirconia and 1-20% by volume, preferably 3-15% by volume, titanium compound-containing cubic phase. If this cubic phase has a lattice spacing of 4.29 to 4.40 .ANG. and a zirconium content of 3-65 weight %, a material with improved performance when turning heat resistant material such as aged Iconel 718, is obtained.Type: GrantFiled: June 20, 1995Date of Patent: April 1, 1997Assignee: Sandvik ABInventors: Mats Andersson, Marianne Collin
-
Patent number: 5612267Abstract: Ceramic preforms comprising monocrystalline hexagonal platelets of .alpha.-alumina, well adopted for conversion into refractory bricks or ceramic composites, are prepared by crystallizing a settled fine powder of amorphous alumina, transition alumina or alumina hydrate, advantageously in the presence of a fluoro-compound flux, into a coherent mass of such hexagonal platelets of .alpha.-alumina.Type: GrantFiled: June 5, 1995Date of Patent: March 18, 1997Assignee: AtochemInventors: Roland Bachelard, Annick Faure
-
Patent number: 5607630Abstract: A ceramic moulded body containing at least 10 vol. % fine-grained Al.sub.2 O.sub.3, and a process for its production(a) milling aluminium metal in powder form alone or together with Al.sub.2 O.sub.3 or/and if desired further suitable inorganic substances for ceramic formation in a non-aqueous liquid in the presence of oxygen until 10 to 80% of the metallic aluminium powder has reacted to form one or several aluminium oxidation precursors from the group amorphous Al.sub.2 O.sub.3, .gamma.-Al.sub.2 O.sub.3 and aluminium-organic compounds and the powder has a maximum oxidation rate between 510.degree. and 610.degree. C. according to differential thermoanalytical measurement;(b) molding the powder of step (a) into a green body;(c) slowly heating the green body in an atmosphere containing oxygen to a temperature which is below the melting temperature of aluminium until at least 50% of the metallic aluminium powder remaining after the milling has reacted to Al.sub.2 O.sub.Type: GrantFiled: September 30, 1994Date of Patent: March 4, 1997Inventor: Nils Claussen
-
Patent number: 5607887Abstract: The present invention provides a method for preparing a ceramic mixed-oxide of at least two metals including mixing an alloy with a ceramic oxide. The alloy including a metal selected from the group consisting of aluminum, calcium, lithium, magnesium, silicon, titanium, yttrium, and zirconium. The alloy also includes an element that is to be present in the ceramic mixed-oxide. The element is different from the metal and is selected from the group consisting of aluminum, calcium, lithium, magnesium, a combination of magnesium and silicon, silicon, titanium, yttrium, and zirconium. The ceramic oxide includes a metal that is to be present in the ceramic mixed oxide. The alloy and ceramic oxide are co-milled. The mixed and co-milled alloy and ceramic oxide are reaction-sintered, thereby oxidizing the metal and element of the alloy to produce the ceramic mixed-oxide.Type: GrantFiled: February 15, 1995Date of Patent: March 4, 1997Assignee: Volvo Aero AktiebolagInventors: Lars Pejryd, Robert Lundberg, Jesper Brandt
-
Patent number: 5603738Abstract: The present invention pertains to a process for preparing an abrasive based on corundum with a grain shape factor exceeding 0.6.Type: GrantFiled: November 14, 1994Date of Patent: February 18, 1997Assignee: Treibacher Schleifmittel AGInventors: Hans Zeiringer, Peter Janz
-
Patent number: 5599867Abstract: A composition for manufacturing a fiber-reinforced molded ceramic body comprises a ceramic powder composed primarily of silicon nitride, inorganic fibers and a binder which are added to the ceramic powder. A fiber-reinforced molded ceramic body is manufactured by producing a slurry from such a composition, pouring the slurry into a mold to produce a fiber-reinforced molded ceramic body, and drying the fiber-reinforced molded ceramic body.Type: GrantFiled: March 28, 1995Date of Patent: February 4, 1997Assignee: Honda Giken Kogyo Kabushiki KaishaInventors: Naoki Ito, Yuji Miki, Atsushi Koizumi, Hiroshi Ichikawa
-
Patent number: 5599756Abstract: A sintered high-toughness alumina-based composite body consisting essentially of a plate- or rod-shaped corundum or alumina-based compound structure, a fine granular corundum structure, and inevitable impurities.Type: GrantFiled: April 7, 1995Date of Patent: February 4, 1997Assignee: Yoshida Kogyo K.K.Inventor: Youji Matsuo
-
Patent number: 5593930Abstract: An object of the present invention is to shorten the working time for high pressure slip casting. There is provided a composition for high pressure casting slip including a first starting powder forming a frame of a mold body and second starting powder forming the frame of the mold body and acting as a plastic agent, wherein the first and second starting powders are uniformly mixed in a dry condition. "Slip" of a minimum water content is easily prepared by the composition to effect optimal fluidity of the slip so that the water is removed from the slip in a short time during a casting process.Type: GrantFiled: September 13, 1995Date of Patent: January 14, 1997Assignee: NGK Insulators, Ltd.Inventor: Ritsu Sato
-
Patent number: 5593468Abstract: The use of purified process materials in the production of a seeded sol-gel alumina abrasive results in an abrasive of superior properties.Type: GrantFiled: July 26, 1995Date of Patent: January 14, 1997Assignee: Saint-Gobain/Norton Industrial Ceramics CorporationInventors: Arup K. Khaund, Ajay K. Garg, Ralph Bauer
-
Patent number: 5589426Abstract: This invention provides monolithic refractories comprising 100% by weight of refractory aggregate powders, and in addition thereto, based on the weight of refractory aggregate powers, 0.05 to 5% by weight of a binder which is phosphate glass and/or hydroxycarboxylates and 0.01 to 1% by weight of a thickener, characterized in that said monolithic refractories have been kneaded with water or other kneading liquid. The monolithic refractories are capable of being applied without being kneaded at working sites.Type: GrantFiled: July 9, 1993Date of Patent: December 31, 1996Assignee: Taikorozai Co., Ltd.Inventors: Itsutoshi Iwasaki, Tatsuo Yamasaki, Hideaki Sawada
-
Patent number: 5587010Abstract: The present invention provides a process for producing fine flaky alumina particles suitable as a raw material for ceramics, a pigment for paint and etc., wherein aluminum hydroxide or alumina hydrate having a particle size regulated to the order of submicron is subjected to a hydrothermal treatment in water or an aqueous alkali solution at a temperature of 350.degree. C. or above under a pressure of 200 kg/cm.sup.2 or below. The present invention further provides an alumina-based plastic material which is produced by kneading the aforesaid fine flaky particles with an organic water holding material and water. Methylcellulose, polyvinyl alcohol, carboxymethylcellulose, polyethylene glycol, etc. are preferably used as the organic water holding agent. The alumina-based plastic material has a high plasticity, so that there is no need of using a large amount of a binder. Thus a dense molded article having stable properties can be prepared.Type: GrantFiled: June 16, 1995Date of Patent: December 24, 1996Assignees: Agency Of Industrial Science And Technology, Ministry Of International Trade And Industry, YKK CorporationInventors: Yasuo Shibasaki, Kiichi Oda, Takeshi Fukuda
-
Patent number: 5587346Abstract: A sintered, translucent ceramic article comprises alpha alumina and up to 0.050 wgt. percent magnesia and between 0.001 to 0.100 wgt. percent lutetium oxide. In a preferred embodiment, the lutetium oxide is at 0.050 wgt. percent and in a second preferred embodiment half the lutetium oxide is replaced by yttrium oxide. A method of making a translucent ceramic article comprises the steps of: forming an aqueous slurry to yield one of the composition described above; adding nitric acid to adjust the pH to 4.6; adding an aqueous binder and plasticizer in the amount of 2.5 solids wgt. percent; spray-drying the slurry; forming an article by wet-bag isopressing; prefiring said article in air at about 1325.degree. C. for about 2 hours; and sintering said air-fired article in hydrogen for about 3 hours at 1800.degree. C.Type: GrantFiled: June 16, 1995Date of Patent: December 24, 1996Assignee: Osram Sylvania, Inc.Inventor: Karlene J. Zuk
-
Patent number: 5580832Abstract: A method of forming a highly dispersed ceramic powder slurry is provided prising forming an aqueous based slurry of a ceramic powder and a polyelectrolyte at an acidic pH and adjusting the pH of the slurry to an alkaline value.Type: GrantFiled: April 26, 1995Date of Patent: December 3, 1996Assignee: The United States of America as represented by the Secretary of CommerceInventors: Subhaschandra G. Malghan, Ramannair S. Premachandran
-
Patent number: 5580834Abstract: A self-sintered silicon carbide/carbon-graphite composite material having interconnected pores which may be impregnated, and a raw batch and process for producing the composite material, is provided. The composite material comprises a densified, self-sintered matrix of silicon carbide, carbon-graphite inclusions and small amounts of any residual sintering aids, such as boron and free carbon, and has interconnected pores which may be impregnated with resin, carbon, TEFLON, metal or other compounds or materials selected for their particular properties to achieve desired tribological characteristics for a specific application. The composite material is produced from a raw batch which includes silicon carbide, sintering aids, a temporary filler and coated graphite particles. The raw batch is then molded/shaped into a green body and heated to carbonize any carbonizable materials and to decompose and volatilize the organic filler to form a matrix of interconnected pores.Type: GrantFiled: February 25, 1994Date of Patent: December 3, 1996Assignee: The Morgan Crucible Company plcInventor: Mark E. Pfaff
-
Patent number: 5569320Abstract: This invention provides a process for preparing a refractory molded article comprising the steps of (a) forming a molded article matrix from an aggregate and the first binder, (b) impregnating the molded article matrix formed in step (a) with the second binder consisting of an alcoholic solution of one kind or two or more kinds of metal alkoxides selected from alkoxides of metals of Group 4A or Group 4B (excepting carbon) and Group 3A or Group 3B of the periodic table and their partial hydrolysates and an alkaline compound of alkali metal or alkaline earth metal (one kind or a mixture of two or more kinds selected from alkoxides, hydroxides and salts of the metal) and (c) drying and firing the molded article matrix at high temperature and also provides a binder for the preparation of such refractory molded article.Type: GrantFiled: December 28, 1994Date of Patent: October 29, 1996Assignees: Cadic Corporation, KSP Inc., Tama Chemicals Co., Ltd.Inventors: Nobuyoshi Sasaki, Tetsuya Yokokawa, Yoshikazu Hashimoto, Yoshiro Ohta, Hideo Sekiguchi
-
Patent number: 5569547Abstract: A ceramic composite material consisting of single crystal .alpha.-Al.sub.2 O.sub.3 and single crystal Y.sub.3 Al.sub.5 O.sub.12 is provided. This composite material has high mechanical strength and creep behavior particularly at high temperatures.Type: GrantFiled: October 4, 1994Date of Patent: October 29, 1996Assignee: Ube Industries, Ltd.Inventors: Yoshiharu Waku, Hideki Ohtsubo, Yasuhiko Kohtoku
-
Patent number: 5569631Abstract: The present invention pertains to a refractory ceramic mass, consisting of 50 to 97 wt. % of sintered MgO as well as 3 to 50 wt. % of a spinel of the hercynite type.Type: GrantFiled: February 7, 1995Date of Patent: October 29, 1996Assignee: Veitsch-Radex Aktiengesellschaft Fur Feuerfeste ErzeugnisseInventors: Harald Harmuth, Roland Heindl, Josef Deutsch
-
Patent number: 5565245Abstract: Mg.sub.x Al.sub.2-2x Ti.sub.1+x O.sub.5 (x.ltoreq.0.2) protective coatings have been developed for both dense and porous substrates, such as SiC and Si.sub.3 N.sub.4, using a chemical solution processing method involving the hydrolysis and condensation of magnesium, aluminum and titanium precursors. The solution viscosities, pH values, H.sub.2 O/alkoxide molar ratios, and dip coating withdrawal rates which are optimum for crack-free Mg.sub.x Al.sub.2-2x Ti.sub.1+x O.sub.5 (x.ltoreq.0.2) are 1.0 to 6.2 cP, pH 1-4.5, molar ratio 1.5-10, and withdrawal rate of 2.2-8.0 cm/min, respectively. Conversion of the amorphous coating to crystalline Mg.sub.x Al.sub.2-2x Ti.sub.1+x O.sub.5 (x.ltoreq.0.2) is achieved by a succession of calcination below 450.degree. C. and a final heat treatment above 1000.degree. C. for ten hours with controlled heating and cooling rates.Type: GrantFiled: March 1, 1995Date of Patent: October 15, 1996Assignee: Virginia Tech Intellectual Properties, Inc.Inventors: Tawei Sun, Nancy R. Brown, Jesse J. Brown, Jr., Min Kang
-
Patent number: 5565392Abstract: A method for making a high strength porcelain for use as an insulator or a structural ceramic, comprising:A) forming a mixture comprising alumina, clay and a fluxing material;B) forming the mixture into a shaped article; andC) firing the shaped article.Type: GrantFiled: June 1, 1995Date of Patent: October 15, 1996Assignee: Raychem CorporationInventors: Karin M. Kinsman, Ryan W. Dupon, Martha L. McCrum, Linas Mazeika, Amy S. Chu
-
Patent number: 5560876Abstract: A process for producing strong, essentially dust-free agglomerates from dust created by an industrial operation carried out, for example, on an ore or mineral, e.g. during the thermal conversion of a material containing predominantly gibbsite to sub-alpha alumina by a multistage thermal process having at least one intermediate stage. The process comprises grinding particles of binder material containing undercalcined alumina to a median particle size of less than 30 microns and to a specific surface area in the range of 90-300 m.sup.2 /g; combining about 1-4 parts by weight of the dust with one part by weight of the ground binder material to form combined solids; mixing the combined solids with water to produce agglomerates, the total amount of added water being about 0.8-1.2 parts by weight for every part by weight of the ground binder material, plus about 0.08 to 0.Type: GrantFiled: May 4, 1995Date of Patent: October 1, 1996Assignee: Alcan International LimitedInventors: Claude Boulanger, Andrew N. Carruthers, Robert L. Clegg, Kwat I. The
-
Patent number: 5552354Abstract: The present invention pertains to a refractory brick based on at least one refractory metal oxide in a particle fraction of <8 mm containing 4 to 30 wt. % of a very fine refractory fraction, prepared by firing below a temperature at which the particles of the very fine refractory fraction sinter by recrystallization with grain growth.Type: GrantFiled: March 16, 1995Date of Patent: September 3, 1996Assignee: Veitsch-Radex Aktiengesellschaft fur Feuerfeste ErzeugnisseInventors: Harald Harmuth, Roland Heindl, Josef Deutsch
-
Patent number: 5552356Abstract: The present invention relates to boron subphosphide/aluminum oxide composite materials, to processes for the production of these materials and to the use thereof.Type: GrantFiled: June 29, 1995Date of Patent: September 3, 1996Assignee: Bayer AGInventor: Nils Perchenek
-
Patent number: 5545598Abstract: Disclosed is a high heat conductive body which consists of 30-99 wt. % of at least one of molybdenum and tungsten and 1 or more wt. % ceramic. A wiring base substrate fitted with such a high heat conductive body is also disclosed. Methods of producing such a high heat conductive body and a wiring base substrate are further disclosed.Type: GrantFiled: February 14, 1994Date of Patent: August 13, 1996Assignee: NGK Spark Plug Co., Ltd.Inventors: Kouki Ogawa, Kozo Yamasaki, Naomiki Kato
-
Patent number: 5538926Abstract: A mixed powder containing: 5-30 wt % of SiC whiskers; 3-30 wt % of a sintering auxiliary agent composed of one kind or more of oxides of Mg, Si, Ca, Ti, Zr, Cr, Ni, Y and rare earth elements; and an Al.sub.2 O.sub.3 powder as a base material; or further containing 0.5-40 wt % of one kind or more of compounds composed of one kind or more of transient elements in the groups IVa, Va, and VIa of the periodic table and one kind or more of C, N and B, are compacted and subjected to pressureless-sintering in a nitrogen containing inert gas atmosphere at a temperature between 1500.degree. and 1900.degree. C. With this method, the SiC whiskers containing Al.sub.2 O.sub.3 based ceramic material, which is densified and has a sufficient strength and toughness, can be formed in a complex shape and a large size.Type: GrantFiled: December 20, 1994Date of Patent: July 23, 1996Assignee: Kabushiki Kaisha Seiko ShoInventors: Takehiro Tsuchida, Tsuneo Tatsuno, Moriyoshi Kanamaru
-
Patent number: 5536686Abstract: A binder for binding reinforcement materials is provided in which an aluminum and/or Group IIa-containing compound is combined, in a liquid, with a phosphorus-containing compound wherein said binder has a ratio of phosphorus to aluminum and/or Group IIa ions of 14 to 34, preferably 20 to 30. The binder is useful in binding reinforcement materials, particularly suited for preparing preforms for making metal matrix composite materials.Type: GrantFiled: October 20, 1992Date of Patent: July 16, 1996Assignee: The Research Foundation of State University of New York at BuffaloInventor: Deborah D. L. Chung
-
Patent number: 5534470Abstract: This invention is directed to the production of thermally crystallizable glasses which, upon heat treatment in contact with alumina particulates, will form a strong glass-ceramic-bonded composite body, the excellent bonding being attributed to the presence of lithium aluminoborate crystals. The glass-ceramic composition consists essentially, in weight percent, of______________________________________ SiO.sub.2 25-55 MgO 0-12 B.sub.2 O.sub.3 35-65 Li.sub.2 O + MgO 4-16. Li.sub.Type: GrantFiled: October 27, 1994Date of Patent: July 9, 1996Assignee: Corning IncorporatedInventors: Ronald l. Andrus, John F. MacDowell
-
Patent number: 5527746Abstract: An aluminum oxide based sintered body and a method for manufacturing the same are disclosed. The aluminum oxide based sintered body is composed of silicon compounds of from about 5 to about 40 mole %, calculated as a carbide, at least one metal or metal compound of from 0.5 to about 25 mole %, calculated as metals, selected from Ti, Nb, Ta, Cr and Mo, and the remainder of Al.sub.2 O.sub.3, and a molar ratio of the metals with respect to the silicon compounds, calculated as a carbide is about 4 or less.Type: GrantFiled: April 5, 1995Date of Patent: June 18, 1996Assignee: NGK Spark Plug Co., Ltd.Inventors: Jun Otsuka, Satoshi Iio, Yo Tajima
-
Patent number: 5525561Abstract: The invention provides a method of making a magnesium/aluminium spinel compound having the formula Mg.sub.(1+x) Al.sub.(2+y) O.sub.4 in which 0.ltoreq.x.ltoreq.0.2 and 0.ltoreq.y.ltoreq.0.35. Particulate aluminium metal and a magnesium-containing component selected from magnesium oxide and precursors thereof are mixed together and heated to 800.degree.-1150.degree. C. in an oxidising environment to cause oxidation of at least part of the aluminium. Further heating then takes place to a temperature of 1150.degree.-1350.degree. C. in the oxidizing environment to cause aluminium oxide and magnesium oxide in the admixture to react together.Type: GrantFiled: October 28, 1994Date of Patent: June 11, 1996Assignee: Programme 3 Patent HoldingsInventor: Arnold Van Zyl
-
Patent number: 5523270Abstract: The present invention broadly relates to novel complex oxidation reaction products such as perovskite bodies, including shaped complex oxidation reaction products. This invention also includes complex oxidation reaction products which exhibit superconducting properties.Type: GrantFiled: June 16, 1994Date of Patent: June 4, 1996Assignee: Lanxide Technology Company, LPInventors: Robert A. Rapp, Andrew W. Urquhart, Alan S. Nagelberg, Marc S. Newkirk
-
Patent number: 5523267Abstract: A silicon nitride-silicon carbide composite sintered material which comprises 100 parts by weight of a silicon nitride component containing 92 to 99.5 mol % of silicon nitride including excessive oxygen and 0.5 to 8 mol % of the elements of Group IIIa in the Periodic Table as corresponding oxides thereof and 1 to 100 parts by weight of a silicon carbide component in a dispersed state, wherein the silicon nitride component has an average particle size of 1 .mu.m or less and an average aspect ratio of 2 to 10, and the silicon carbide component has an average particle size of 1 .mu.m or less, moreover, the total amount of Al, Mg, Ca respectively contained in the sintered material as calculated as oxides thereof is 0.5% by weight or less, and a manufacturing method thereof.According to the above-mentioned composite sintered material, it becomes possible to suppress deterioration of strength at 1400.degree. C. and realize excellent creep properties.Type: GrantFiled: July 18, 1994Date of Patent: June 4, 1996Assignee: Kyocera CorporationInventors: Kouichi Tanaka, Masaki Terazono, Masahiro Satoh, Masahito Nakanishi, Hideki Uchimura, Shoji Kousaka