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WO1992009541A1 - Procede de production de matieres a base de mullite - Google Patents

Procede de production de matieres a base de mullite Download PDF

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Publication number
WO1992009541A1
WO1992009541A1 PCT/US1991/008975 US9108975W WO9209541A1 WO 1992009541 A1 WO1992009541 A1 WO 1992009541A1 US 9108975 W US9108975 W US 9108975W WO 9209541 A1 WO9209541 A1 WO 9209541A1
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WO
WIPO (PCT)
Prior art keywords
composition
mullite
fibers
silica
precursor
Prior art date
Application number
PCT/US1991/008975
Other languages
English (en)
Inventor
Sivananda S. Jada
Original Assignee
Manville Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Manville Corporation filed Critical Manville Corporation
Publication of WO1992009541A1 publication Critical patent/WO1992009541A1/fr

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/624—Sol-gel processing
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/16—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay
    • C04B35/18—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay rich in aluminium oxide
    • C04B35/185—Mullite 3Al2O3-2SiO2
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/62227—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products obtaining fibres
    • C04B35/62231—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products obtaining fibres based on oxide ceramics
    • C04B35/6224—Fibres based on silica
    • C04B35/62245—Fibres based on silica rich in aluminium oxide

Definitions

  • the present invention is concerned with a process for the production of mullite compositions using a sol gel technique.
  • Japanese patent application No. 58-112309, laid open publication No. 60-5022, F. Hashimi et al discloses a process of preparing alumina fibers by forming a spinning dope containing aluminum oxychloride, a silicon compound and urea and calcining the fibers at more than 500"Centigrade. The mixture was concentrated under reduced pressure at 50 ⁇ Centigrade to provide a spinning dope.
  • T. Ando et al describes a process for preparing a refractory insulating board precursor which comprising kneading aluminum material fibers with an alumina content of 75% by weight or more with silica-alumina mixed sol, then molding the mixture by filtration, drying the molded product to prepare a precursor for a refractory insulating board to be used at a temperature of 950"Centigrade or higher.
  • Described is a method of preparing a mullite composition comprising the steps of:
  • the invention is particularly concerned with obtaining mullite in various forms, e.g., fibers and hollow particles from the homogeneous mixture of the silica and the aluminum oxide precursor solutions.
  • FIGURE 1 is a schematic diagram of the process of spray-drying to produce mullite particles
  • FIGURE 2 is a scanning electron microscope (SEM) micrograph of precursor mullite granules at 3500 magnification.
  • the present invention is concerned with obtaining mullite compositions in various forms, e.g., discrete particles, hollow particles, refractory fibers, flakes and the like.
  • One of the initial steps is to prepare a silicon containing aqueous material.
  • the silicon that may be employed can generally be character ⁇ ized as silicon oxides or alkoxides.
  • the silicon oxides can be silicon dioxide or polymers thereof.
  • the silicon alkoxides can be those comprised of the silicon contain ⁇ ing materials further comprising hydrocarbyl containing lower alkyl radicals from 1 to 6 carbon atoms, prefera ⁇ bly ethyl.
  • Illustrative materials are tetramethoxy- silane, tetraethoxysilane, methyltrimethoxysilane, ethyltriethoxysilane and amyltriethoxysilane, and the like.
  • the silicon material be colloidal silica which has an acidic ph, preferably a ph of 3-5.
  • the colloidal silica is preferably in an aqueous state with a particle size less than 50 nanome ⁇ ters, preferably 0.5-25 nanometers.
  • the ph is adjusted from the normal ph of colloidal silica which is basic, usually about 8 to 10 by the use of acidic materials. Any acidic material that does not interfere with subsequent processing steps may be employed whether it be organic or inorganic, although preferably organic acids of less than 6 carbon atoms and even more preferably acetic acid is employed.
  • the aluminum oxide precursor solution can be placed into an aqueous solution and then the two solutions blended to give a homogeneous composition, solution or mixture.
  • the aluminum oxide precursor can be a dispersion or a solution.
  • silica or aluminum oxide useful in this invention are commercially available in the form of aqueous sols, salts or dry powders which can be readily dispersed in water to form sols, such as aluminum oxychloride powder sold under the trademark "Chlorhydrol Micro-Dry”, silica sols sold under the trademark “Nalco”, “Ludox”, and A1 2 0 3 colloidal sol sold under the trademark “Nyacol Al/20”, aluminum acetate basic, sold under the trademark “NiaProof” and alumina powder sold under the trademark "Pural”, “Puralox", and "Disperal”.
  • the precursor material in the form of dispersion, salts or sols of said oxides
  • These compounds representa ⁇ tively include many carboxylates and alcoholates, e.g.
  • acetates formates, oxalates, lactates, propylates, ci ⁇ trates, and acetylacetonates, and oxysalts of mineral and organic acids, e.g., oxybromides, oxychlorides, oxychlorates, oxynitrates, and oxyacetates, and aluminum halides, sulfates, and phosphates, selection of the particular precursor compound being dictated by avail ⁇ ability and ease of handling.
  • Representative precursor compounds are aluminum oxy ⁇ hloride, aluminum oxynitrate, oxyacetates and the like.
  • the A1 2 0 3 precursor can be aluminum alkoxide.
  • the aluminum alkoxides can be those of the aluminum containing materials further comprising hydrocarbyl containing lower alkyl radicals from 1 to 15 carbon atoms, preferably isopropyl.
  • Illustrative materials are aluminum tri-sec-butoxide, aluminum tri-tert-butoxide, aluminum triethoxide, aluminum n-butoxide, aluminum sec- butoxide stearate, aluminum t-butoxide, aluminum di- (sec-butoxide) acetoacetic esterchelate, aluminum di(iso-propoxide, aluminum phenoxide, and the like.
  • the most preferred material is aluminum oxychloride which on sintering gives the aluminum oxide.
  • Controlled amounts of additives and/or mineralizers are added as sintering aids to reduce the higher tempera ⁇ tures required for mullite formation and also as grain- growth inhibitors and mullite toughening agents.
  • the additives added most frequently include Fe 2 0 3 , Cr 2 0 3 , Ti0 2 , Zr0 2 , Ga 2 0 3 , MgO, Na 2 0, K 2 0, B 2 0 3 and V 2 0 3 .
  • Zro 2 increases the toughness of mullite by a grain-boundary- strengthening mechanism by adding up to 0.05 wt% Zr0 2 .
  • the Na 2 0, Fe 2 0 3 and B 2 0 3 reduce the temperature of mullite formation and crystallization.
  • B 2 0 3 is a preferred ineralizer (concentrations ⁇ 2%) added to the precursor solution in the form of boric acid.
  • the colloidal silica be a very fine particle size.
  • the silica concentration should be less than 50% and preferably approximately 10- 30%, and even more preferably, about 20% by weight.
  • the purpose in adding the acidic material is to produce a negative electrostatic charge on the silica particles.
  • Colloidal silica particles exhibit a significant nega ⁇ tive electrostatic charge in the ph range of from 3 to 5 and a value within this range is selected for matching with the ph of the aqueous aluminum oxide precursor solution.
  • the ph adjusted colloidal silica solution is added to the slurry containing the desired metal oxide precursor solutions and the mixture is stirred, prefer- ably in the presence of ultrasonic treatment to facili ⁇ tate the reaction.
  • the colloidal silica particles with a negative electrostatic charge are attracted to the positively charged aluminum ion. (For example, the zeta potential for alumina at a ph of 3-5 is approximately 45-50 millivolts) .
  • the ratio of silica to alumina be at the ratio of 2 moles of silica to 3 moles of aluminum oxide.
  • ultrasonic treatment may be utilized.
  • the process parameters are such that ambient temperature and pressure are utilized and the frequency used ranges from 0.01 to 1 kilohertz.
  • the concentration ranges from 10 to 80%.
  • the viscosity of the solution ranges from l to 40 Centipoise (CPS) . Thereafter, the solution or mixture of materials which approaches the gel state is dried.
  • the final physical formation of the mullite compositions can be obtained in a number of ways.
  • One technique would be merely to allow the mixture to evaporate to dryness.
  • the evaporation can be accelerated by heating at a temperature from ambient to 100"Centigrade. In this fashion, the water and other volatile components can be readily removed therefrom.
  • the dried material could be flakes or other particulate to form. It may be ground to a desired size.
  • the mullite precursor composition can also be spray-dried using the apparatus described in Figure l.
  • the particles are subjected to a sintering or calcining treatment to obtain the desired ceramic particles.
  • the sintering temperature is at least 250° to 1500°, and even more preferably, about 900° to 1200"Centigrade.
  • FIG. 1 shows the schematic diagram of the apparatus useful in the present invention.
  • a tank 10 is a reservoir of the aqueous liquid 12.
  • the tank is open to the atmosphere at the top as indicated by arrows 14.
  • the tank is operated at ambient pressure.
  • a second tank 16 is one that likewise contains liquid 12 which passes from the tank 10 to the tank 16 by pipe 17.
  • the cavity 20 is one that is exposed to atmospheric pres ⁇ sure, for it is the cavity above the reservoir in the tank 10.
  • a similar cavity 22 is atop the reservoir 12 above the level 24 of the fluid in the reservoir 16.
  • the lower tank 16 likewise is open to the atmosphere as is indicated by arrow 26.
  • Line 18 maintains equal pressure in tanks 10 and 16.
  • the liquid transfer tube 28 is attached to nozzle means generally shown as reference numeral 30.
  • the inlet 32 for the liquid is placed adjacent to the air inlet 34 which is connected to an air pump generally expressed as 36.
  • the nozzle 30 is generally available from Spraying Systems, Inc. of Wheaton, Illinois, and is utilized in this invention as follows. When air from pump 36 passes through conduit 34 and air outlet 38, the liquid composition from reservoirs 12 and 24 pass through conduit 32 and is atomized into heated chamber 40. The spray nozzle 30 is locked in position by lock nut 42 onto an appropriately configured vessel 44. The top portion 46 of the nozzle is appropriately configured to lock in place at position 48 which is at the bottom of container 40.
  • the spray 50 from the air pump is schematically shown in Figure l.
  • the orifice 38 is preferably 0.016 inches in diameter and the orifice 33 of conduit 32, ranges from 0.05 inches for the inner diameter to 0.064 inches for the outer diameter or .007 inches.
  • the air is fed through conduit 34 at a range of 5 to 100 pounds per square inch gauge (psig) , and even more preferably, 10 to 70 psig, most preferably, 15 to 30 psig.
  • Two of the interior walls of heat chamber 40 have four 500 watt strip heaters attached to black painted aluminum plates attached to the interior of the walls of the reservoir 40.
  • the heating of the chamber preferably exceeds 250"F, and even more preferably, 400" - 1000"F.
  • the non-spraying temperature would drop a minimum of 100"F during spraying.
  • the microspheres or particles that are pro ⁇ quizzed preferably have a size less than 75 microns with a lower limit of approximately 1 micron.
  • the size range is preferably 10 to 60 microns, and even more prefera ⁇ bly, 15 to 50 microns.
  • particles that are not hollow may be produced. This may be accom- plished by modifying the processing conditions such as a lower drying temperature and a higher viscosity homogeneous solution that is spray-dried.
  • an alternative particle collection device can be anything commercially available such as a cyclone collection system with a separate system for separating and collating the partic- ulates depending upon the sizes desired for particles.
  • compositions that is spun can be quite high in concentration of the mullite composition, preferably greater than 55% by weight mullite precursor, and even more preferably, greater than 60% by weight up to approximately 75% by weight. The most preferred is having at least 65% solids of the spinning composition.
  • organic polymers such as natural or synthetic polymers having fiber- forming ability.
  • organic polymers such as natural or synthetic polymers having fiber- forming ability.
  • soluble derivatives of starch or cellulose such as starch acetate, hydroxy- ethyl starch, methyl cellulose, carboxymethyl cellulose, ethyl cellulose, hydroxypropyl cellulose, and the like may be employed.
  • Other materials may be synthetic polymeric materials such as polyvinyl alcohol, polyeth ⁇ ylene glycol, polyacrylamide and the like.
  • polyethylene oxide having a molecular weight of 1,000 to 600,000 may also be employed.
  • the amount of polymeric material is an effective amount which ranges from l to 20% by weight of mullite.
  • the most preferred physical form of the mullite is fibrous.
  • the fibers may be formed from any general fiber forming technique. The most preferred is to feed viscous precursor material through a spinnerette which output is then subjected to forced air to form long strands of fibers. The fibers are subsequently collected and calcined.
  • the physical materials are sub- jected to a sintering or a calcining treatment to obtain the desired crystalline composition.
  • the sintering temperature is at least 250 - 1500"Centigrade, and even more preferably, about 900 - 1200"Centigrade.
  • the fibers formed will have lengths that range from 0.5 to 20 centimeters and diameters in the range of 0.05 to 10 microns with an average fiber diameter being the range of 1.5 to 5 microns, preferably less than 3 microns.
  • any process of manufacturing the fiber may be utilized as in the making of fiberglass from a melt can be applicable.
  • the dope that is utilized is a highly viscous dope. Therefore, the steam blown process would be applicable, namely, that the dope is forced through jets and is subjected to air from jets to volatilize the aqueous or other organic portion of the precursor mullite composition.
  • Forcing the dope through rotating spinnerettes likewise can be used as a technique for forming fibers.
  • the fiber may be fed to a continuous belt where it could be lead to be oven- cured and subsequently to the calcining as indicated previously.
  • the spinnerette can be rotating thereby forcing the dope through the holes in the spinnerette.
  • the mullite could then subsequently be formed into products as desired by forming a roving or board for insulation purposes.
  • the mullite compositions can be utilized for refractory purposes such as insulation of heated products or in appliances such as ovens, microwaves and the like.
  • thermal shields used in space exploration equipment, missiles, rockets and in commercial and military aircraft for heat and/or fire protection in voice record box, engine parts, fuselage.
  • a poly(tetraethylorthosilicate) solution was prepared as follows:
  • a mullite composition was formed from Disperal (trademark of Condea A1 2 0 3 sol powder - 60% A1 2 0 3 ) by adding 101.96g of A1 2 0 3 sol dissolved in 900g of water with 2g of acetic acid. Small portions of A1 2 0 3 powder were added with vigorous agitation. Sio 2 sol, (Ludox brand) having 3.5-4.0 ph (adjusted from 9.9 by adding acetic acid 5g, to ⁇ O.llg Ludox) was added into middle of the A1 2 0 3 powder addition.
  • Mullite fiber could be formed from the follow ⁇ ing composition:
  • Aluminum acetate dibasic Al(OH) 2 CH 3 COO; Mol. wt. : 120.0412 from Niacet Corp:
  • Aluminum acetate has 36% by weight A1 2 0 3
  • PEO polyethyleneoxide from Polysciences, Inc.
  • Azeotropic mixture was made by adding an equal amount (250 ml) of ethanol. The mixture was subjected to a rotary evaporation to remove 400 ml of ethanol + water giving 163.Og of residue.
  • the fibers were formed by feeding a viscous mass of 8,000 to 60,000 centipoise to a centrifugal spinning machine with a 5 3/8" diameter disk having multiple holes of 0.012" in their smallest dimension. Air ring pressure was maintained at 7 psig. The ambient relative humidity was maintained and the ambient temper ⁇ ature between 80 and 100"F. The mullite fiber precursor temperature at the beginning of the run was between 25 and 70"F and the disc temperature was between 80 and 100"F.
  • Fibers formed by above step were spread on a stainless steel tray and subjected to a heat treat cycle as follows: 250 C, 1 hr.,
  • LudoxTM 18Og In a separate beaker, take LudoxTM 18Og and to that add 180g (equal amount) of water. Then add 4-5g of acetic acid. Add this ph adjusted LudoxTM to a solution of 558.lg aluminum oxychloride (50% by wt) in 500 ml ethanol. Mix thoroughly.
  • Figure 2 shows mullite precursor granules at 3500 times magnification from an SEM micro- graph. .An analysis of the spray-dried granules is: % C:2.99; % H:1.82; % Cl: ⁇ 0.53; % Al:27.2; %Si:18.41.
  • the spray-dried material was sintered at 250"C for 1 hour; 650°C for 1 hour and finally at 1000"C for 48 hours.
  • the oven was cooled to room temperature.
  • the products were tested by spectroscopic and X-ray diffrac ⁇ tion tests for chemical composition and were determined to be mullite particles. Furthermore, the calcined mullite particles were hollow as evidenced by electron micrographs.
  • Hollow mullite particles were prepared in the same manner as in Example 5 except that % w/w of B 2 0 3 by the weight of mullite was added as boric acid to the precursor solution.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Silicates, Zeolites, And Molecular Sieves (AREA)

Abstract

Procédé de préparation d'une composition à base de mullite comprenant les étapes consistant à former une composition aqueuse contenant de la silice ayant un pH acide, à former une solution précurseur aqueuse d'oxyde d'aluminium, à former un mélange homogène de la composition de silice et de la composition d'oxyde d'aluminium, à solidifier la composition précurseur de mullite à partir de la solution homogène, à fritter le précurseur de mullite solidifié, et à récupérer la composition de mullite formée.
PCT/US1991/008975 1990-12-03 1991-12-02 Procede de production de matieres a base de mullite WO1992009541A1 (fr)

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US62162490A 1990-12-03 1990-12-03
US621,624 1990-12-03

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5739373A (en) * 1992-11-20 1998-04-14 Monsanto Company Optically active phosphono analogs of succinates and synthesis thereof
DE10117470A1 (de) * 2001-04-06 2002-10-17 Univ Bayreuth Verfahren zur Herstellung von Mullit und Mullitbauteil
EP1264804A1 (fr) * 2001-06-08 2002-12-11 Japan Vilene Company, Ltd. Procédé de fabrication d'une pièce en matériau inorganique, pièce en matériau inorganique et substrate de circuit
WO2007054697A1 (fr) * 2005-11-10 2007-05-18 The Morgan Crucible Company Plc Fibres resistantes aux temperatures elevees
WO2021068737A1 (fr) * 2019-10-09 2021-04-15 清华大学 Matériau aérogel à fibre de mullite flexible et son procédé de préparation
WO2022034072A1 (fr) * 2020-08-12 2022-02-17 Deutsche Institute Für Textil- Und Faserforschung Denkendorf Multifibres renforcées par du zro2, procédés pour la fabrication de celles-ci et leur utilisation
CN115182074A (zh) * 2022-07-15 2022-10-14 中南大学 一种稀土氧化镧改性的氧化铝-莫来石纤维及其制备方法
CN118684233A (zh) * 2024-08-23 2024-09-24 山东工业陶瓷研究设计院有限公司 一种单相莫来石溶胶的制备及其快速凝胶的方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3503765A (en) * 1966-02-14 1970-03-31 Babcock & Wilcox Co High temperature alumina-silica fibers and method of manufacture
EP0005198A1 (fr) * 1978-05-08 1979-11-14 International Business Machines Corporation Procédé de fabrication d'un matériau céramique dense contenant de la mullite très pure
EP0116436A2 (fr) * 1983-02-03 1984-08-22 Alcan International Limited Sols d'alumine
JPS6175818A (ja) * 1984-09-21 1986-04-18 Nippon Light Metal Co Ltd アルミナ質繊維の製造方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3503765A (en) * 1966-02-14 1970-03-31 Babcock & Wilcox Co High temperature alumina-silica fibers and method of manufacture
EP0005198A1 (fr) * 1978-05-08 1979-11-14 International Business Machines Corporation Procédé de fabrication d'un matériau céramique dense contenant de la mullite très pure
EP0116436A2 (fr) * 1983-02-03 1984-08-22 Alcan International Limited Sols d'alumine
JPS6175818A (ja) * 1984-09-21 1986-04-18 Nippon Light Metal Co Ltd アルミナ質繊維の製造方法

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
CHEMICAL ABSTRACTS, vol. 109, no. 16, 17 October 1988, Columbus, Ohio, US; abstract no. 133859C, S.SOMYA ET AL.: 'MANUFACTURE OF STOICHIOMETRIC MULLITE ULTRAFINE POWDER' page 298 ; *
JOURNAL OF THE AMERICAN CERAMIC SOCIETY vol. 72, no. 3, March 1989, WESTERVILLE,OHIO,US pages 377 - 382; M.MIZUNO ET AL.: 'PREPARATION OF HIGHLY PURE FINE MULLITE POWDER' *
WORLD PATENTS INDEX LATEST Week 8622, Derwent Publications Ltd., London, GB; AN 86-140525 & JP,A,61 075 818 (NIPPON LIGHT METAL KK ET AL.) 18 April 1986 *

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5739373A (en) * 1992-11-20 1998-04-14 Monsanto Company Optically active phosphono analogs of succinates and synthesis thereof
DE10117470A1 (de) * 2001-04-06 2002-10-17 Univ Bayreuth Verfahren zur Herstellung von Mullit und Mullitbauteil
EP1264804A1 (fr) * 2001-06-08 2002-12-11 Japan Vilene Company, Ltd. Procédé de fabrication d'une pièce en matériau inorganique, pièce en matériau inorganique et substrate de circuit
US6808670B2 (en) 2001-06-08 2004-10-26 Japan Vilene Co., Ltd. Process for manufacturing inorganic article
EP1577274A3 (fr) * 2001-06-08 2005-11-30 Japan Vilene Company, Ltd. Pièce en matériau inorganique et substrate de circuit
WO2007054697A1 (fr) * 2005-11-10 2007-05-18 The Morgan Crucible Company Plc Fibres resistantes aux temperatures elevees
AU2006313594B2 (en) * 2005-11-10 2011-06-09 Morgan Advanced Materials Plc High temperature resistant fibres
US8163377B2 (en) 2005-11-10 2012-04-24 The Morgan Crucible Company Plc High temperature resistant fibres
WO2021068737A1 (fr) * 2019-10-09 2021-04-15 清华大学 Matériau aérogel à fibre de mullite flexible et son procédé de préparation
WO2022034072A1 (fr) * 2020-08-12 2022-02-17 Deutsche Institute Für Textil- Und Faserforschung Denkendorf Multifibres renforcées par du zro2, procédés pour la fabrication de celles-ci et leur utilisation
CN115182074A (zh) * 2022-07-15 2022-10-14 中南大学 一种稀土氧化镧改性的氧化铝-莫来石纤维及其制备方法
CN115182074B (zh) * 2022-07-15 2024-01-30 中南大学 一种稀土氧化镧改性的氧化铝-莫来石纤维及其制备方法
CN118684233A (zh) * 2024-08-23 2024-09-24 山东工业陶瓷研究设计院有限公司 一种单相莫来石溶胶的制备及其快速凝胶的方法

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