With Drying, Calcining, Or Sintering Of Non-shaped Particulate Patents (Class 264/661)
  • Patent number: 10017423
    Abstract: A method for preparing a support of a molecular sieve membrane is provided and relates to a technical field of support preparation, including steps of: according to a molar ratio of magnesium, aluminum and silicon in cordierite, preparing a nanometer composite sol of magnesium, aluminum, silicon and lanthanum serving as a sintering aid through a sol-gel method, enveloping and bonding the sol on a surface of dispersed nano-sized cordierite powders, and transforming the sol into nanometer composite oxides through presintering; mixing the cordierite powders, a binder and water, forming mud, extruding the mud, forming the mud into a green body, and sintering the green body into a cordierite support; coating a layer of film on the cordierite support with an aqueous dispersant of zirconia, then sintering, and obtaining a support of a molecular sieve membrane, composited by a cordierite main support layer and a zirconia film layer.
    Type: Grant
    Filed: July 22, 2016
    Date of Patent: July 10, 2018
    Assignee: SHANDONG GUIYUAN ADVANCED CERAMICS CO., LTD
    Inventors: Fanpeng Meng, Zhenkun Fan, Jian Zhang, Chao Zhang
  • Patent number: 9802868
    Abstract: Disclosed is a ceramic sintered shaped body containing Y2O3-stabilized zirconia with a sintered density of at least 99% of the theoretical sintered density and having a mean grain size of <180 nm. The zirconia fraction of the sintered shaped body comprises tetragonal and cubic phases. Also disclosed is a process for the production of a ceramic sintered shaped body containing Y2O3-stabilized zirconia, which process comprises dispersion of a submicron powder and comminution of the dispersed submicron powder by means of grinding media having a diameter of less than or equal to 100 ?m to a particle size d95 of <0.42 ?m; shaping of the dispersion to form a body, and sintering of the body to form the sintered shaped body.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: October 31, 2017
    Assignee: FRAUNHOFFER-GESELLSCHAFT ZUR FOERDERUNG DER ANGEWANDTEN FORSCHUNG E. V.
    Inventors: Martina Johannes, Jens Schneider
  • Patent number: 9126846
    Abstract: A method of synthesizing metal composite oxide, the method including: a step of separately introducing into a high-speed stirring apparatus a ceria composite oxide microparticle colloid having a mean particle diameter of 10 nm or less after adding a dispersant and an alumina microparticle colloid having a mean particle diameter of 10 nm or less after adding a dispersant; a step of synthesizing alumina-ceria composite oxide microparticles by allowing the ceria composite oxide microparticles and the alumina microparticles that have been introduced into the high-speed stirring apparatus to react in a microscopic space; and a step of applying a shearing force of 17000 sec?1 or more to the alumina-ceria composite oxide microparticles.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: September 8, 2015
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Satoshi Nagao, Kimiyasu Ono, Hirohito Hirata, Akihiko Suda, Kimitoshi Sato, Kae Yamamura, Akira Morikawa
  • Publication number: 20130309308
    Abstract: The present invention relates to a method of converting limestone into tri-calcium phosphate (TCP) and tetra-calcium phosphate (TTCP) powder simultaneously. In particular, the method provides for a method of converting limestone into TCP and CTTCP powder simultaneously having specific particle size and with specific crystallographic structure.
    Type: Application
    Filed: September 29, 2011
    Publication date: November 21, 2013
    Applicant: SIRIM Berhad
    Inventors: Fazilah Binti Fazan, Sudirman Bin Sahid, Wan Ruzaini Bin Wan Sulaiman, Norshahida Binti Kader Bashah
  • Publication number: 20130224465
    Abstract: A ceramic block consisting essentially of substantially homogeneous (Y2O3)? P2O5, where 0.95?x?1.05, having length LL, a width WW and a height HH, and a volume W of at least 8×10?3 m3 essentially free of cracks throughout the volume, a density of at least 85% of the theoretical maximal density of Y203.P2O5 under standard conditions, and a creep rate CR at 1250° C. and 6.89 MPa; where CR?8.0×10?6 hour?1 and method for making the same. The method utilizes a dry process where the starting YP04-based ceramic material is synthesized by reacting anhydrous P2O5 with dry Y2O3 powder.
    Type: Application
    Filed: October 25, 2011
    Publication date: August 29, 2013
    Inventors: Ralph Alfred Langensiepen, Joseph James McIntosh, Tracey Lynn Timmons
  • Patent number: 8512589
    Abstract: Disclosed is a MnZn ferrite core comprising basic components, subcomponents and unavoidable impurities. To the basic components comprising: iron oxide (as Fe2O3): 51.0-54.5 mol %, zinc oxide (as ZnO): 8.0-12.0 mol % and manganese oxide (as MnO): remainder, are added silicon oxide (as SiO2): 50-400 mass ppm and calcium oxide (as CaO): 50-4000 ppm as subcomponents and in the unavoidable impurities, phosphorous, boron, sulfur and chlorine are respectively kept to: less than 3 mass ppm, less than 3 mass ppm, less than 5 mass ppm, and less than 10 mass ppm. The ratio of the measure specific surface area to the ideal specific surface area of the MnZn ferrite core satisfies the formula: Measured specific surface area/ideal specific surface area<1500.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: August 20, 2013
    Assignee: JFE Chemical Corporation
    Inventors: Hirofumi Yoshida, Yukiko Nakamura, Satoshi Goto
  • Publication number: 20130162101
    Abstract: A dielectric sintered body of the present invention contains Ba, Nb, and at least one of Zn and Co, as main components, and K and Ta as subcomponents. The ratio A of the peak intensity p2 of the (111) plane peak to the peak intensity p1 of the (310) plane peak in an X-ray diffraction measurement is 0.9 to 1.5. The half bandwidth C of the (111) plane peak ranges from 0.12 to 0.22°. The d-value D of the (111) plane peak ranges from 2.363 to 2.371. The dielectric sintered body has a Perovskite structure.
    Type: Application
    Filed: September 2, 2011
    Publication date: June 27, 2013
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Satoru Fujita, Yuki Kasuya
  • Patent number: 8282878
    Abstract: Embodiments of the present invention disclosed herein include a sintering aid composition that has a material useful for sintering, an amine, and optionally a carboxylic acid.
    Type: Grant
    Filed: January 27, 2011
    Date of Patent: October 9, 2012
    Assignee: Huntsman Petrochemical LLC
    Inventors: Alan P. Croft, David C. Lewis
  • Patent number: 8241715
    Abstract: The present invention relates to a container packing structure, characterized in that it comprises a crystalline phase containing 55 to 97% by weight of xonotlite crystallites and 3 to 45% by weight of tobermorite crystallites. It also relates to a method for fabricating such a packing structure, and the container containing same, and its use for storing fluids such as gases.
    Type: Grant
    Filed: September 8, 2010
    Date of Patent: August 14, 2012
    Assignee: L'Air Liquide Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Gilles Cannet, Pascal Del Gallo, Thierry Chartier, Emmanuel Baune, Jérome Cantonnet, Jean-François Imbault
  • Publication number: 20110284364
    Abstract: A sputtering target precursor material comprises a homogeneous distribution of a ZnAl2O4 phase in a hexagonal ZnO phase, said ZnO phase further comprises less than 1 wt % of elemental Al in solid solution, expressed versus the total weight of said target material.
    Type: Application
    Filed: May 16, 2011
    Publication date: November 24, 2011
    Applicant: UMICORE
    Inventors: Nikolaus MARGADANT, Guido HUYBERECHTS, Paul LIPPENS, Anke BRÖNSTRUP
  • Patent number: 7814679
    Abstract: An abrasive is fabricated to obtain sliding and grinding effects. In the abrasive, grinding particles are wrapped by a wrapping material. Various sizes and shapes of molds and micro components can be finely polished to obtain mirror-grade surfaces.
    Type: Grant
    Filed: April 21, 2008
    Date of Patent: October 19, 2010
    Assignee: National Central University
    Inventors: Biing-Hwa Yan, Feng-Che Tsai, Li-Wen Sun
  • Publication number: 20100120607
    Abstract: A glass-free microwave dielectric ceramic that can be sintered at low temperature, and a manufacturing method thereof are provided. The glass-free microwave dielectric ceramic composition includes a composition represented by a formula, M2+N4+B2O6, wherein M is one element of Ba, Ca and Sr, and N is one element of Sn, Zr and Ti. The M may be replaced by two elements of Ba, Ca and Sr different from each other, to form a composition represented by a formula, (M1-x2+Mx2+)N4+B2O6, wherein 0<x<1. The N may also be replaced by two elements of Sn, Zr and Ti different from each other, to form a composition represented by a formula, M2+(N1-y4+Ny4+)B2O6, wherein 0<y<1. Furthermore, it is also possible to replace both of the M and N to form a composition represented by a formula, (M1-x2+Mx2+)(N1-y4+Ny4+)B2O6, wherein 0<x<1 and 0<y<1.
    Type: Application
    Filed: November 22, 2007
    Publication date: May 13, 2010
    Applicant: Korea Institute of Ceramic Engineering & Technolog y
    Inventors: Hyo Tae Kim, Jong Hee Kim, Myung Hwa Nam
  • Publication number: 20090197757
    Abstract: Densified zinc oxide ceramics can be obtained so that transparent electrodes with good characteristics can be obtained using the ceramics as a sputtering target. This manufacturing method is used to manufacture the zinc oxide ceramics doped with Al in ZnO. This method comprises, calcination powder production process by which calcination powder is produced after blending Al2O3 powder and a 1st ZnO powder and by calcinating them, and sintering process by which said zinc oxide ceramics are manufactured after sintering formed body composed of powder before the sintering which is made by blending said calcination powder and a 2nd ZnO powder. Here, the ceramics are manufactured not by sintering a formed body composed of Al2O3 powder and ZnO powder, but by sintering the formed body composed of the calcination powder containing ZnAl2O4 phase and ZnO powder.
    Type: Application
    Filed: August 6, 2007
    Publication date: August 6, 2009
    Applicant: HITACHI METALS, LTD.
    Inventor: Hideko Fukushima
  • Patent number: 7534388
    Abstract: A ceramic component is disclosed, including a sintered ceramic body from a composition comprising a first ceramic material, and a plurality of inclusions in the ceramic body, each inclusion comprising graphite and a second material.
    Type: Grant
    Filed: March 11, 2005
    Date of Patent: May 19, 2009
    Assignee: Saint-Gobain Ceramics & Plastics, Inc.
    Inventors: Vimal K. Pujari, Jeffrey J. Kutsch
  • Patent number: 7524546
    Abstract: A thermal insulating material which can be efficiently produced while the content of organic matters, such as organic fibers and/or an organic binder, is reduced to the same or lower degree as compared with the thermal insulating material used in a conventional pollution control device (e.g., catalytic converter), and which can be applied to a pollution control element (e.g., catalytic element) while avoiding, as much as possible, an unpleasant feeling to the operator. A thermal insulating material comprising a thermal insulating material body formed of a bulk material of inorganic fibers, and a coating provided on at least one surface of said thermal insulating material body.
    Type: Grant
    Filed: December 13, 2001
    Date of Patent: April 28, 2009
    Assignee: 3M Innovative Properties Company
    Inventors: Takuma Aizawa, Toshihiro Kasai, Takayuki Kawai, Toshiyuki Watanabe
  • Patent number: 7521389
    Abstract: A precursor composition for the production of granulated ceramic material, particularly for ceramic proppants, comprises 20 to 55% by weight of magnesium orthosilicate, 20 to 35% by weight of MgO, and 2.5 to 11% by weight of Fe2O3. The resulting lightweight proppant material shows high mechanical strength. To further decrease the specific density of the proppant, the formation of small pores can be increased by adding 0.3 to 2.4% carbon as a gas-forming agent.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: April 21, 2009
    Assignee: Ilem Research and Development Establishment
    Inventors: Sergey Shmotev, Sergey Pliner
  • Publication number: 20090014927
    Abstract: A cemented carbide cutting tool insert/button for mining and construction comprising hard constituents in a binder phase of Co and/or Ni and at least one surface portion and an interior portion in which surface portion the grain size is smaller than in the interior portion is disclosed. The surface portion with the smaller grain size has a lower binder phase content than the interior portion. A method to form the cemented carbide cutting tool insert/button is also disclosed.
    Type: Application
    Filed: August 11, 2008
    Publication date: January 15, 2009
    Inventors: Mathias TILLMAN, Susanne Norgren, Marianne Collin
  • Patent number: 7387752
    Abstract: Methods for producing solid, substantially round, spherical and sintered particles from a slurry of a calcined, uncalcined or partially calcined raw material having an alumina content of greater than about 40 weight percent. The slurry is processed with spray drying methods into solid, substantially round, spherical and sintered particles having an average particle size greater than about 200 microns, a bulk density of greater than about 1.40 g/cc, and an apparent specific gravity of greater than about 2.60.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: June 17, 2008
    Assignee: CARBO Ceramics Inc.
    Inventors: Steve Canova, Thomas C. Palamara, Jimmy C. Wood
  • Patent number: 6803086
    Abstract: There are provided a porous honeycomb structure body capable of satisfying a pressure loss and isostatic strength which are mutually contradictory properties simultaneously and a method for manufacturing the same. In a porous honeycomb structure body having partition walls which contain cordierite as a primary crystal phase and have a porosity of 40 to 75% and an average pore diameter of 10 to 50 &mgr;m, porosity and an average pore diameter in a center portion of the structure body are made larger than porosity and an average pore diameter in a peripheral portion of the structure body.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: October 12, 2004
    Assignee: NGK Insulators, Ltd.
    Inventors: Yasushi Noguchi, Yukihisa Wada, Yumi Muroi
  • Patent number: 6777114
    Abstract: It is directed to a silicon carbide-based porous body, wherein said body is a porous one which contains silicon carbide particles as an aggregate and metallic silicon, and has an oxygen-containing phase at the surfaces of silicon carbide particles and/or metallic silicon or in the vicinity of the surfaces thereof. The silicon carbide-based porous body contains refractory particles such as silicon carbide particles or the like and yet can be produced at a relatively low firing temperature at a low cost, has a high thermal conductivity, and is superior in oxidation resistance, acid resistance, chemical resistance to ash and particulates.
    Type: Grant
    Filed: August 13, 2002
    Date of Patent: August 17, 2004
    Assignee: NGK Insulators, Ltd.
    Inventors: Takahiro Tomita, Shuichi Ichikawa, Shinji Kawasaki, Hiroaki Sakai
  • Patent number: 6746748
    Abstract: A honeycomb structure made of a silicon carbide-based porous body and having a number of through-holes extending in the axial direction, separated by partition walls. The strength and Young's modulus of the silicon carbide-based porous body satisfy the following relation: Strength (MPa)/Young's modulus (GPa)≧1.1. The honeycomb structure contains refractory particles such as silicon carbide particles and the like and yet can be produced at a relatively low firing temperature at a low cost, has a high strength and a high thermal shock resistance, and can be suitably used, for example, as a filter for purification of automobile exhaust gas by a treatment such as plugging of through-channel at its inlet or outlet, or as a catalyst carrier, even under a high SV condition.
    Type: Grant
    Filed: August 12, 2002
    Date of Patent: June 8, 2004
    Assignee: NGK Insulators, Ltd.
    Inventors: Shuichi Ichikawa, Takahiro Tomita, Shinji Kawasaki, Hiroaki Sakai
  • Patent number: 6716512
    Abstract: A honeycomb structure having, in the axial direction, a number of through-channels separated by partition walls, which honeycomb structure contains refractory particles and a vitreous component and is porous. Although the honeycomb structure contains refractory particles such as silicon carbide particles or the like, it can be produced at a relatively low firing temperature; therefore, the honeycomb structure has a low production cost and a high yield and can be provided at a low price.
    Type: Grant
    Filed: September 14, 2001
    Date of Patent: April 6, 2004
    Assignee: NGK Insulators, Ltd.
    Inventors: Yoshinori Yamamoto, Naomi Noda, Takashi Harada
  • Patent number: 6709628
    Abstract: The invention relates to a process for production of a sintered oxide ceramic of composition CexMyDzO2-a with dense structure without open porosity or with a predetermined porosity. The first doping element M is at least one element of the group consisting of the rare earths but M≠Ce, alkali and earth alkali metals. The educts are used with a second doping element D of at least one metal of the group consisting of Cu, Co, Fe, Ni and Mn, in the submicron particle size or as a salt solution, and sintered at a temperature in the range of 750-1250° C. into an oxide ceramic with extremely fine structure of a grain size of maximum around 0.5 &mgr;m.
    Type: Grant
    Filed: January 17, 2001
    Date of Patent: March 23, 2004
    Assignee: Eidgenossische Technische Hochschule Zurich Nichtmetallische Werkstoffe
    Inventors: Christoph Kleinlogel, Martin Goedickemeier, Ludwig Gauckler
  • Patent number: 6649244
    Abstract: A ceramic honeycomb catalyst carrier wherein a porosity is 20% or less and an average surface roughness (Ra) of a partition wall of the carrier is 0.5 &mgr;m or more is obtained by forming ceramic raw materials to obtain a ceramic honeycomb formed body; drying the ceramic honeycomb formed body to obtain a ceramic honeycomb dried-up body; roughening a surface of the partition wall of the ceramic honeycomb dried-up body by exposing the ceramic honeycomb dried-up body in an airflow in which polishing powders are included; and sintering the ceramic honeycomb dried-up body after a surface treatment, or, by forming ceramic raw materials to obtain a ceramic honeycomb formed body; drying and sintering the ceramic honeycomb formed body to obtain a ceramic honeycomb sintered body; and roughening a surface of the partition wall of the ceramic honeycomb sintered body by exposing the ceramic honeycomb sintered body in an airflow or a water flow in which polishing powders are included.
    Type: Grant
    Filed: January 17, 2002
    Date of Patent: November 18, 2003
    Assignee: NGK Insulators, Ltd.
    Inventors: Toshiyuki Hamanaka, Kyoko Makino, Yasushi Noguchi
  • Patent number: 6592805
    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.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: July 15, 2003
    Assignee: National University of Singapore
    Inventors: John Wang, Junmin Xue, Leong Ming Gan, Ser Choon Ng, Leong Chew Lim
  • Publication number: 20030003160
    Abstract: The present invention is directed to a synthetic biomaterial compound based on stabilized calcium phosphates and more particularly to the molecular, structural and physical characterization of this compound. The compound comprises calcium, oxygen and phosphorous, wherein at least one of the elements is substituted with an element having an ionic radius of approximately 0.1 to 1.1 Å. The knowledge of the specific molecular and chemical properties of the compound allows for the development of several uses of the compound in various bone-related clinical conditions.
    Type: Application
    Filed: May 10, 2002
    Publication date: January 2, 2003
    Inventors: Sydney M. Pugh, Timothy J.N. Smith, Michael Sayer, Sarah Dorthea Langstaff
  • Patent number: 6485672
    Abstract: A method of manufacturing a dielectric ceramic composition comprising at least a main component of BaTiO3, a second subcomponent as represented by (Ba, Ca)xSiO2+x (where, x=0.8 to 1.2), and other subcomponents. The main component and at least part of the subcomponents except the second subcomponent are mixed to prepare a pre-calcination powder and the pre-calcination powder is calcined to prepare a calcined powder. The second subcomponent is at least mixed in the calcined powder to obtain a dielectric ceramic composition having a ratio of each subcomponent to the main component of BaTiO3 of a predetermined molar ratio.
    Type: Grant
    Filed: October 24, 2000
    Date of Patent: November 26, 2002
    Assignee: TDK Corporation
    Inventors: Takeshi Nomura, Shigeki Sato
  • Patent number: 6403019
    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.
    Type: Grant
    Filed: November 6, 2000
    Date of Patent: June 11, 2002
    Inventors: Tsutomu Fukuda, Masahiro Fukuda, Masaaki Fukuda
  • Publication number: 20020041061
    Abstract: A method of production of a dielectric ceramic composition having at least a main component of Ba2TiO3, a second subcomponent including at least one compound selected from SiO2, MO (where M is at least one element selected from Ba, Ca, Sr, and Mg), Li2O, and B2O3, and other subcomponents, comprising the step of: mixing in said main component at least part of other subcomponents except for said second subcomponent to prepare a pre-calcination powder, calcining the pre-calcination powder to prepare a calcined powder, and mixing at least said second subcomponent in said calcined powder to obtain the dielectric ceramic composition having molar ratios of the subcomponents to the main component of predetermined ratios. As the other subcomponents, there is a third subcomponent including at least one compound selected from V2O5, MoO3, and WO3. A ratio of the third subcomponent to 100 moles of the main component is preferably 0.01 to 0.1 mole.
    Type: Application
    Filed: August 20, 2001
    Publication date: April 11, 2002
    Applicant: TDK CORPORATION
    Inventors: Takeshi Nomura, Shigeki Sato
  • Patent number: 6028021
    Abstract: A microwave dielectric composition superior in all dielectric constant, product of resonant frequency by quality coefficient and temperature-dependent coefficient of resonant frequency, can be prepared by mixing a main oxide formulation consisting of lead oxide, calcium oxide, zirconium oxide and tin oxide with manganous nitrate (Mn(NO.sub.3).sub.2.4H.sub.2 O), calcining the mixture at a temperature of about 1,000 to 1,200.degree. C., pulverizing and molding the mixture, and sintering the molded body at a temperature of about 1,200 to 1,550.degree. C. in an oxygen atmosphere. It is 100 or greater in dielectric constant, 4,000 or greater in the product of resonant frequency by quality coefficient and .+-.3 mmp/.degree. C. or less in temperature-dependent coefficient of resonant frequency.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: February 22, 2000
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Ho Gi Kim, Yung Park, Tae Suk Chung
  • Patent number: 5928773
    Abstract: A neutral pH foamed glass article is produced from a mixture of pulverized glass particles, foaming agent, binder, and water, wherein the glass article is heated to remove excess moisture and organic materals, then further heated to cause the foaming agent to emit a foaming gas, thereby causing foaming of the glass article. The foamed glass article is annealed in a controlled cooling fashion to avoid thermal stress, cracking and devitrification. The foamed glass articles may be used as artificial pumice stones in the stone-washed garment industry. Preferably, the mixture contains an amount of lignosulfonate to produce foamed glass having substantially neutral pH values in a range of from about 7.0 to 8.4.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: July 27, 1999
    Assignee: Vitric Corporation
    Inventor: James C. Andersen
  • Patent number: 5894008
    Abstract: A method of manufacturing an alumina-silicon carbide nanocomposite having particular application to improved ball bonding capillaries of a wire bonding device produces a structure with a 93-98 volume percent of .alpha.-alumina having an average diameter of 0.1-0.3 .mu.m, a 2-7 volume percent of .beta.-silicon carbide having an average diameter of 0.1-1.5 .mu.m, a bending strength of 340-550 Mpa, and a toughness of 3.3-4.1 Mpam.sup.1/2.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: April 13, 1999
    Assignees: Anam Industrial Co., Ltd., Amkor Electronics, Inc.
    Inventor: Seok Ho Na
  • Patent number: 5854158
    Abstract: A ZrO.sub.2 based ceramic material having excellent mechanical strength and fracture toughness comprises a first phase of ZrO.sub.2 grains containing CeO.sub.2 as a stabilizer and having an average grain size of 5 .mu.m or less, a second phase of Al.sub.2 O.sub.3 grains having an average grain size of 2 .mu.m or less, and a third phase of elongated crystals of a complex oxide of Al, Ce, and one of Mg and Ca. At least 90 vol % of the first phase is composed of tetragonal ZrO.sub.2. An aluminum (Al) content in the ceramic material is determined such that when Al of the complex oxide is converted to Al.sub.2 O.sub.3, a total amount of Al.sub.2 O.sub.3 in the ceramic material is within a range of 0.5 to 50 vol %. A content of the third phase in the ceramic material is determined within a range of 0.5 to 5 by area %. It is preferred that fine Al.sub.2 O.sub.3 grains having an average grain size of 1 .mu.m or less of the second phase are dispersed within the ZrO.sub.2 grains at a dispersion ratio of at least 2%.
    Type: Grant
    Filed: June 11, 1997
    Date of Patent: December 29, 1998
    Assignee: Matsushita Electric Works, Ltd.
    Inventors: Masahiro Nawa, Shoichi Nakamoto, Koichi Niihara, Tohru Sekino
  • Patent number: 5824262
    Abstract: These methods relate to the preparation of a YBa.sub.2 Cu.sub.3 O.sub.7 -d catalyst for purifying an exhaust gas. The method comprises steps of mixing Y.sub.2 O.sub.3, Ba.sub.2 CO.sub.3 and CuO at a mole ratio of 1:4:6, respectively; grinding the resultant mixture to obtain fine powder having a size of at least 200 mesh; sintering the fine powder at temperature of 800.degree. C. to 900.degree. C. under an atmosphere of oxygen; annealing the fine powder to room temperature; pelletizing the powder to form pellets; grinding the pellets to obtain fine powder having a size of at least 200 mesh; re-sintering the resultant fine powder at a temperature of 800.degree. C. to 920.degree. C.; and re-annealing the fine powder to room temperature.
    Type: Grant
    Filed: February 23, 1996
    Date of Patent: October 20, 1998
    Assignee: Kia Motors Corporation
    Inventors: Sang-Ho Kim, Kyu-Hun Choi, Sok-Jin Chung
  • Patent number: 5795537
    Abstract: The present invention provides a method of producing composite oxide ceramics which is capable of efficiently producing single-phase multi-component metal oxide ceramics having less impurity phase and excellent dielectric characteristics, by a simple process comprising sintering at a low temperature. The method has the steps of mixing a metallic hydroxide or hydrous gel with a plurality of metallic oxide powders to prepare a raw material mixture powder, activating the raw material mixture powder by mechanochemical treatment for grinding the raw material mixture powder with a degree of impact, which provides a centrifugal effect of 15 or more, to form a precursor, and synthesizing composite oxide ceramics by heat treatment of the activated raw material mixture powder (precursor).
    Type: Grant
    Filed: August 7, 1996
    Date of Patent: August 18, 1998
    Assignee: Nara Machinery Co., Ltd.
    Inventors: Mamoru Senna, Sang-Hee Cho, Kenji Hamada
  • Patent number: 5762864
    Abstract: A lightweight artificial aggregate manufacturing method includes the steps of: mixing aggregate sludge, whose moisture content exceeds 30%, with stone fragments, generated when pulverizing stone, to decrease the moisture content, mixing this mixture and sewage disposal plant sludge, which are dried and micro-pulverized, in a weight ratio of 50 to 50, and making the mixed sludge spheroids with a rotary plate molding device; applying paper sludge, which is dried and micro-pulverized, to the surface of the spheroids in order to prevent condensation of the spheroid during burning and to light the weight of aggregate; burning the spheroid with reducing flame of a temperature between 1000.degree. C. and 1200.degree. C. in a burning furnace, which uses gas or oil as fuel; and cooling the burned spheroid.
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: June 9, 1998
    Assignee: Gom Remicon Co., Ltd.
    Inventor: Yong Deuk Park
  • Patent number: 5656213
    Abstract: A process for producing a carbon-filled ceramic composite material comprising a ceramic matrix and a carbon domain dispersed therein with a carbon domain diameter of from 0.01 to 30 .mu.m and a carbon domain area ratio of from 5 to 70%; comprising the steps of mixing ceramic powder, sintering aids and a carbon source, calcining the mixture at 300.degree.-600.degree. C., granulating the mixture, molding and sintering.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: August 12, 1997
    Assignee: Kao Corporation
    Inventors: Mikio Sakaguchi, Kazuhiro Otsuka