EP2454214A1 - Céramiques composites de titanate d'aluminium et de magnésium - Google Patents

Céramiques composites de titanate d'aluminium et de magnésium

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Publication number
EP2454214A1
EP2454214A1 EP10734423A EP10734423A EP2454214A1 EP 2454214 A1 EP2454214 A1 EP 2454214A1 EP 10734423 A EP10734423 A EP 10734423A EP 10734423 A EP10734423 A EP 10734423A EP 2454214 A1 EP2454214 A1 EP 2454214A1
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EP
European Patent Office
Prior art keywords
ceramic
firing
mgo
tio
mixture
Prior art date
Legal status (The legal status 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 status listed.)
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Application number
EP10734423A
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German (de)
English (en)
Inventor
Satoko Iwato
Rina YAMANAKA
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EIDP Inc
Original Assignee
EI Du Pont de Nemours and Co
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Publication date
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Publication of EP2454214A1 publication Critical patent/EP2454214A1/fr
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    • 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
    • C04B35/46—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 titanium oxides or titanates
    • C04B35/462—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 titanium oxides or titanates based on titanates
    • C04B35/478—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 titanium oxides or titanates based on titanates based on aluminium titanates
    • 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
    • C04B35/64—Burning or sintering processes
    • C—CHEMISTRY; METALLURGY
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    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/0006—Honeycomb structures
    • C—CHEMISTRY; METALLURGY
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    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00793—Uses not provided for elsewhere in C04B2111/00 as filters or diaphragms
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
    • C04B2235/3206—Magnesium oxides or oxide-forming salts thereof
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
    • C04B2235/3222—Aluminates other than alumino-silicates, e.g. spinel (MgAl2O4)
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3418—Silicon oxide, silicic acids, or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3427—Silicates other than clay, e.g. water glass
    • C04B2235/3463—Alumino-silicates other than clay, e.g. mullite
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/36—Glass starting materials for making ceramics, e.g. silica glass
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/44—Metal salt constituents or additives chosen for the nature of the anions, e.g. hydrides or acetylacetonate
    • C04B2235/441—Alkoxides, e.g. methoxide, tert-butoxide
    • C—CHEMISTRY; METALLURGY
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    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/44—Metal salt constituents or additives chosen for the nature of the anions, e.g. hydrides or acetylacetonate
    • C04B2235/449—Organic acids, e.g. EDTA, citrate, acetate, oxalate
    • 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
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
    • C04B2235/5436—Particle size related information expressed by the size of the particles or aggregates thereof micrometer sized, i.e. from 1 to 100 micron

Definitions

  • the present invention relates to aluminium magnesium titanate composite ceramics for forming particulate filters, which are characterized by a relatively high porosity, low thermal expansion efficiency (CTE), and high mechanical strength of which measurement are used a flexural strength, and to a process for its production.
  • CTE thermal expansion efficiency
  • Particulate filters are used to remove particulate matter (PM) such as soot and ash in exhaust gas produced by compression ignition internal combustion engines, i.e., diesel engines.
  • PM particulate matter
  • particles that collect on an exemplary honeycomb structure filter that traps the particles in its pores and along its walls can be removed from the filter through
  • DPF diesel particulate filter
  • WO2004/039747 discloses aluminium magnesium titanate having excellent mechanical strength represented by a flexural strength and having an elemental composition ratio of Al, Mg and Ti represented by a formula (T):
  • coefficient x satisfies 0.1 ⁇ x ⁇ 1.
  • Alkali feldspar ((Na y Ki -y )AISi3 ⁇ 8, wherein y satisfies 0 ⁇ y ⁇ 1 ) is added to enhance sintering of aluminum magnesium titatane because of its low melting point.
  • Such ceramics are desired to have a low CTE as well as more excellent mechanical strength represented by a flexural strength.
  • U.S. Patent 5,153, 153 discloses sintered ceramic material which comprises doped aluminum titanate and mullite having the composition: 50-61.5 % AI 2 O 3 ,36-47.5 % titanate oxide,2.5-5 % SiO 2 , with the sum total of the three components adding up to 100%, and which further comprises 0.3-1 % MgO 0.015 to 0.5% iron oxide and up to 1 % impurities, being useful as particle filters in diesel engine.
  • such ceramic material are time consuming and expensive to produce, and it is not possible to attain the required properties such as the porosity and thermal shock resistance through the particulate filter formation. This is because iron oxide component influences strength of aluminum magnesium titanate ceramics at high temperature.
  • the present invention is directed to an aluminium magnesium titanate composite ceramic of which the main component is represented by the empirical formula Mg x Al2(i- x ) Ti(-
  • coefficient x satisfies 0 ⁇ x ⁇ 0.1
  • the firing raw materials as expressed on a weight percent oxide basis, 36.0 - 57.0 % of TiO 2 ; 41.5 - 62.0% Of AI 2 O 3 ; and 0 - 2.2 % of MgO, with the sum total of the three components adding up to 100%, and 0 - 10% of SiO 2 .
  • a second embodiment of the present invention is directed to a process for producing an aluminium magnesium titanate composite ceramic of which the main component is represented by the empirical formula Mg x Al2(i- ⁇ ) Ti(i+ X ) ⁇ 5 (wherein coefficient x satisfies 0 ⁇ x ⁇ 1 ), comprising the following raw materials, as expressed on a weight percent oxide basis, 36.0 - 57.0 % of TiO 2 ; 41.5 - 62.0% of AI 2 O 3 ; and 0 - 2.2 % of MgO, with the sum total of the three components adding up to 100%, and 0 - 10% of SiO 2 , which comprising the firing said raw materials at a temperature not lower than 1 ,300 0 C.
  • Mg x Al2(i- x ) Ti(i +X ) ⁇ 5 (wherein coefficient x satisfies 0 ⁇ x ⁇ 0.1 ) as a result of firing a mixture comprising TiO 2 , AI 2 O 3 , MgO, and SiO 2 , as expressed on a weight percent oxide basis of 36.0 - 57.0 % of TiO 2 ; 41.5 - 62.0% of AI 2 O 3 ; and 0 - 2.2 % of MgO with the sum total of the TiO 2 , AI 2 O 3 , MgO adding up to 100%, and the addition of 0 - 10% Of SiO 2 .
  • This ceramic has been shown to have a coefficient of thermal expansion (30- 1000 0 C) of less than 3x10 "6 (1/K) and a porosity of at least 28% by volume of the pore space of the ceramic body.
  • the ceramic of the present inventions has also been shown by Applicants to have a flexural strength of greater than about 8MPa according to JIS R1601. It is preferred that the ceramic of the present invention is fired at a temperature in a range from 1200 0 C to 1700 0 C.
  • Another embodiment of the present invention is a process for producing a ceramic comprising the following steps: a) combining TiO 2 , AI 2 O 3 , MgO, and SiO 2 to form a mixture, as expressed on a weight percent oxide basis of 36.0 - 57.0 % Of TiO 2 ; 41.5 - 62.0% Of AI 2 O 3 ; and 0 - 2.2 % of MgO with the sum total of the TiO 2 , AI 2 O 3 , MgO adding up to 100%, and the addition of 0 - 10% of SiO 2 ; b) mixing the mixture; b) drying the mixture, c) firing the mixture at a temperature in a range from 1200 0 C to 1700 0 C.
  • the drying step is at a temperature from 110°C to 130 0 C and the mixing occurs by a wet process in a ball mill.
  • the mixture may include a grinding aid, a dispersant, an anti-foaming agent, or a combination of one or more thereof.
  • the process of the present invention also may include the steps of grinding the ceramic after firing, placing the ground ceramic in a mold, and then firing the ground ceramic in the mold to create a shaped ceramic.
  • the aluminium magnesium titanate composite ceramic of the present invention primarily comprises, on an oxide basis, 36-57.0% Ti- containing compound, 41.5-62.0% Al-containing compound, 0-2.2% Mg- containing compound, with the sum total of the three components adding up to 100%, and 0- 10% Si-containing compound, which are formed by mixing and firing the mixture of the compounds.
  • the aluminium magnesium titanate composite ceramic of the present invention may optionally comprise other additives such as titanate oxide; alumina; Magnesium oxide; silica; MgAI 2 O 4 ; mullite; and the like, provided that their presence does not appreciably or deleteriously increase the CTE of the composite ceramic.
  • the CTE becomes high because of the excess amount of AI 2 O3.
  • the CTE becomes high because of the excess amount Of TiO 2 .
  • the AI 2 O 3 content is below 41.5 wt%
  • the CTE becomes high because of the excess amount of TiO 2
  • the AI 2 O 3 content is above 62.0 wt%
  • the CTE becomes high because of the excess amount Of AI 2 O 3 .
  • MgO when the amount of MgO is above 2.2 wt%, enough high porosity cannot be obtained.
  • SiO 2 when the SiO 2 content is above 10 wt%, CTE becomes high.
  • the aluminium magnesium titanate composite ceramic of the present invention primarily comprises, on an oxide basis, 37.5-49.0% Ti-containing compound, 50.0-61.5% Al-containing compound, 0-2.2% Mg-containing compound, with the sum total of the three
  • the aluminum magnesium titanate composite ceramic may not comprise other component such as titanate oxide; alumina; Magnesium oxide; silica; MgAI 2 O 4 ; mullite; and the like as much as possible except for aluminum magnesium titanate itself which is represented by the empirical formula Mg x Al2(i- ⁇ ) Ti(i+ x )Os (wherein coefficient x satisfies 0 ⁇ x ⁇ 0.1 ).
  • the amount of Si-containing compound in the ceramic material is preferably in the range of 0-7% on an oxide basis.
  • the aluminum magnesium titanate composite ceramic of the present invention primary comprises, on an oxide basis, 38.3-43.9% Of TiO 2 , 55.5- 61.5% of AI 2 O 3 , 0-1.0% of MgO, with the sum total of the three
  • the titania source is a compound to be a titanium ingredient to constitute aluminium magnesium titanate, and for example, includes titanium oxide.
  • Titanium oxide includes, for example, titanium(IV) oxide, titanium(lll) oxide, titanium(ll) oxide, etc.
  • Preferred is titanium(IV) oxide.
  • the crystal type of titanium(IV) oxide includes an anatase type, a rutile type, a brookite type, etc., and may be amorphous. More preferred are an anatase type and a rutile type.
  • the titania source includes a powder of a compound to be led to titania (titanium oxide) by firing alone in air.
  • the compound includes, for example, titanium salt, titanium alkoxide, titanium hydroxide, titanium nitride, titanium sulfide, titanium metal, etc.
  • the titanium salt concretely includes titanium trichloride, titanium tetrachloride, titanium(IV) sulfide, titanium(VI) sulfide, titanium(IV) sulfate, etc.
  • the titanium alkoxide concretely includes titanium(IV) ethoxide, titanium(IV) methoxide, titanium(IV) t-butoxide, titanium(IV) isobutoxide, titanium(IV) n-propoxide, titanium(IV) tetraisopropoxide, and their chelate compounds, etc.
  • the titania source is preferably titanium oxide.
  • the alumina source in the mixture is a compound to be the aluminium ingredient constituting aluminium magnesium titanate, and, for example, includes a powder of alumina (aluminium oxide).
  • the crystal type of alumina includes a ⁇ -type, a ⁇ -type, a ⁇ -type, an ⁇ -type and others, and may be amorphous.
  • As the alumina preferred is an ⁇ -type alumina.
  • the alumina source also includes a compound capable of being led into alumina by firing alone in air.
  • the compound includes, for example, aluminium salt, aluminium alkoxide, aluminium hydroxide, metal aluminium, etc.
  • the aluminium salt may be an inorganic salt with an inorganic acid, or an organic salt with an organic acid.
  • the aluminium inorganic salt includes, for example, aluminium nitrate salts such as aluminium nitrate, ammonium aluminium nitrate, etc.; aluminium carbonate salts such as ammonium aluminium carbonate, etc.
  • the aluminium organic salt includes, for example, aluminium oxalate, aluminium acetate, aluminium stearate, aluminium lactate, aluminium laurate, etc.
  • the aluminium alkoxide includes, for example, aluminium isopropoxide, aluminium ethoxide, aluminium sec-butoxide, aluminium tert-butoxide, etc.
  • the crystal type of aluminium hydroxide includes, for example, a gibbsite type, a bayerite type, a norstrandite type, a boehmite type, a pseudo-boehmite type, etc., and may be amorphous.
  • Amorphous aluminium hydroxide includes, for example, an aluminium hydrolyzate to be obtained by hydrolysis of an aqueous solution of a water-soluble aluminium compound such as aluminium salt, aluminium alkoxide, etc.
  • the alumina source is preferably alumina.
  • the magnesia source is a compound to be a magnesium ingredient to constitute aluminium magnesium titanate, and for example, includes a powder of magnesia (magnesium oxide).
  • the magnesia source also includes a compound capable of being led into magnesia by firing alone in air.
  • the compound includes, for example, magnesium salt, magnesium alkoxide, magnesium hydroxide, magnesium nitride, metal magnesium, etc.
  • the magnesium salt concretely includes magnesium chloride, magnesium perchlorate, magnesium phosphate, magnesium
  • magnesium pyrophosphate magnesium oxalate, magnesium nitrate, magnesium carbonate, magnesium acetate, magnesium sulfate, magnesium citrate, magnesium lactate, magnesium stearate, magnesium salicylate, magnesium myristate, magnesium gluconate, magnesium dimethacrylate, magnesium benzoate, etc.
  • the magnesium alkoxide concretely includes magnesium methoxide, magnesium ethoxide, etc.
  • magnesia source usable is a compound serving both as a magnesia source and an alumina source.
  • the compound includes, for example, magnesia spinel (MgAI 2 O 4 ).
  • the silica source is a compound to give a silicon ingredient to be in the aluminium magnesium titanate composite ceramic, and for example, includes silicon oxide (silica) such as silicon dioxide, silicon monoxide, etc.
  • the silica source also includes a powder of a compound capable of being led into silica by firing alone in air.
  • the compound includes, for example, silicic acid, silicon carbide, silicon nitride, silicon sulfide, silicon tetrachloride, silicon acetate, sodium silicate, sodium orthosilicate, glass frit, etc. Preferred are glass frit and the like, from the viewpoint of industrial availability.
  • the silica source also usable is a compound additionally serving as an alumina source.
  • the compound includes, for example, an aluminosilicate containing at least one element selected from Na, K and Ca and containing Si and Al.
  • the name of aluminosilicate is feldspar, and the feldspar may be a natural substance or a synthetic product, and the synthetic product is industrially available with ease.
  • silica source also usable is a compound additionally serving as a titanate source, an alumina source, and magnesium source.
  • Example of such compound includes any of titanate source, alumina source and/or Magnesium source, coated with silica source on a surface thereof.
  • the alumina source, the magnesia source and the titania source are generally used as powder.
  • the mixture can be obtained, for example, by mixing an alumina source, a magnesia source and a titania source.
  • the mixing may be attained by dry process or by wet process.
  • an alumina source, a magnesia source and a titania source may be mixed, preferably with stirring and grinding along with grinding media in a grinding container for producing an aluminium magnesium titanate composite ceramic having a uniform composition.
  • additives such as a grinding aid, a deflocculant or a dispersant, an anti-foaming agent (defoamer which shali be understood to mean a substance that is used to reduce foaming) and the like may be added thereto.
  • a grinding aid e.g., a grinding aid, a deflocculant or a dispersant, an anti-foaming agent (defoamer which shali be understood to mean a substance that is used to reduce foaming) and the like
  • an anti-foaming agent defoamer which shali be understood to mean a substance that is used to reduce foaming
  • Dispersanls suitable for purposes of the present invention may be selected from the group consisting of any anionic, cation sc or non-ionic dispersant, or combinations thereof.
  • An example of a suitable dispersant is an isobutylene nialeic acid copolymer, Na salt, sold under the tradename OrotanTM 731 by Rohm and Haas, Examples of conventional "anti-foaming agents " will be appreciated by those having skill in the field to which the invention pertains.
  • a suitable antifoaming agent is a blend of modified fatty alcohols and polysiloxane sold under the tradenarne Dehydran " TM 1620 by Cognis Corp.
  • the grinding aid includes, for example, alcohols such as methanol, ethanol, propanol, etc.; glycols such as propylene glycol, polypropylene glycol, ethylene glycol, etc.; amines such as triethanolamine, etc.; higher fatty acids such as palmitic acid, stearic acid, oleic acid, etc.; carbon materials such as carbon black, graphite, etc. One or more of these may be used either singly or as combined.
  • alcohols such as methanol, ethanol, propanol, etc.
  • glycols such as propylene glycol, polypropylene glycol, ethylene glycol, etc.
  • amines such as triethanolamine, etc.
  • higher fatty acids such as palmitic acid, stearic acid, oleic acid, etc.
  • carbon materials such as carbon black, graphite, etc.
  • One or more of these may be used either singly or as combined.
  • the aluminium magnesium titanate composite ceramic of the invention By firing the mixture, the aluminium magnesium titanate composite ceramic of the invention can be obtained.
  • the mixture may be fired while powdery, or may be fired after shaped.
  • the powdery mixture may be shaped, for example, according to a pressing method or the like.
  • the firing temperature may be generally from 1200 0 C to 1700 0 C from the viewpoint of easy production of aluminium magnesium titanate and from the practicability, preferably from 1400 0 C to 1600 0 C.
  • the heating rate up to the firing temperature may be generally from 10°C/hr to 500°C/hr
  • the firing may be attained generally in air; but depending on the type and the blend ratio of the starting materials (the alumina source, the magnesia source, the titania source and optionally the silica source) to be used, the firing may be attained in an inert gas such as nitrogen gas, argon gas or the like, or may be attained in a reducing gas such as carbon monoxide gas, hydrogen gas or the like. During the firing, the water vapor pressure in the atmosphere may be reduced.
  • an inert gas such as nitrogen gas, argon gas or the like
  • a reducing gas such as carbon monoxide gas, hydrogen gas or the like.
  • the firing is attained using an ordinary firing furnace such as a tubular electric furnace, a boxy electric furnace, a tunnel furnace, a far-IR furnace, a microwave heating furnace, a shaft furnace, a
  • the firing may be attained by batch process or by continuous process, and may be attained in a static mode or a fluidized mode.
  • the time to be taken for the firing may be a time enough for production of aluminium magnesium titanate from the mixture, and may vary depending on the amount of the mixture used, the type of the firing furnace, the firing temperature, the firing atmosphere and others, but may be generally from 10 minutes to 24 hours.
  • the firing temperature is at least 1 ,200 0 C.
  • the grinding and classification may be conducted by general methods such as a ball mill, a media mill, a roll mill, a hammer mill, a pin mill, a jet mill, a planetary mill, a vibrating mill, grinding by hands or by a mortar.
  • the obtained grind aluminum magnesium titanium powders may be classified by general classification methods.
  • the average particle size (D50) of the powder of aluminum magnesium titanium composite ceramics is about 10 to 60 micron meters.
  • the composite ceramic can have a coefficient of thermal expansion (RT30-1000 0 C) of less than 3x10 "6 (1 /K).
  • the CTE (30 -
  • 1000 0 C can range from -3x10 "6 to 3x10 "6 (1/K).
  • the composite ceramic can have a porosity of at least 28%, specifically at least 30% by volume as a measure of the percent volume of pore space of the fired ceramic.
  • the percent volume can range from 25 to 60% by volume.
  • the composite ceramic can have a flexural strength of greater than about 8 MPa according to JIS R1601.
  • the flexural strength can range from 6 MPa to 40 MPa.
  • Porosity (percent by volume) with respect to a rectangular shaped specimen of 3 mm x 4 mm x 40 mm, which was cut out from the second sintered shaped ceramic, was calculated by the following:
  • CTE coefficient of Thermal Expansion
  • Average Particle size (D 50 ) of each material was measured using a laser diffraction technique such as LA-920 commercially available from Horiba Ltd.; is calculated using JIS R16222 and 1629
  • titanium oxide powder, ⁇ -alumina powder and magnesium oxide of which the components were as shown in Table 1 ,with the sum total of the three components adding up to 100%, and 5 parts by mass of silica powder, 1.5 parts by mass of Orotan 731 (sold by Rohm & Haas)(10% aq.) as dispersantjsobutylene maleic acid copolymer, Na salt, 0.2 parts by mass of a blend of modified fatty alcohols and polysiloxane sold under the tradename DehydranTM sold by Cognis Corp (10% aq.) as antifoam agent and 100 parts by mass of water were put into a grinding container along with alumina balls (diameter 15 mm), and stirred and mixed by wet process in a ball mill for 5 hours. Then the mixture was dried at 120 deg.C for about 12 hours to get raw material mixture.
  • ⁇ -alumina powder AI2O3, Sumitomo Chemical, "AES-12” Titanium oxide powder: TiO2, DuPont, "R-900".
  • Magnesium oxide MgO, Konoshima Kagaku K.K.,
  • Dispersing agent Orotan (trade mark)731 ( (10% aq.),isobutyiene rnaleic acid copolymer, Na salt, commercially available from Rohm & Hass.
  • Anti-foaming agent Dehydran TM 1620, a blend of modified fatty alcohols and a poiysiioxane from Cognis Corp., Ambler, PA.
  • the obtained raw material mixtures were put in aluminum saggers, and were fired in a boxy electric furnace under the below profiling in the air. After cooling the sintered materials to room temperature, aluminum magnesium titanate composite ceramics were obtained.
  • RT Room Temperature(RT) - 1450deg.C, where RT is room temperature (about 20 to 25°C) for 30 hours
  • the obtained sintered material was ground and classified to get grind powder with average grain size of about 24 micron meter.
  • 10 g of the obtained grind powder was taken out, and put into a rectangular mold with the size of 10 mm x 10 mm x 50 mm, and pressed under a shaping pressure of 120 kgf/cm 2 , thereby giving a shaped ceramic.
  • the shaped ceramic was again fired in air in a boxy electric furnace under the firing temperature and time as shown in the Table 1 , thereby giving a second sintered shaped ceramic.
  • MgO contents 0 to about 2 wt% are preferred.
  • Example 3 to 5 and Comparative Example 3 were carried out in the same manner as in Example 1 to 2, except that, the compositions and the firing temperature of shaped ceramics were as shown in Table 2.
  • composition range of 41.5 to 62.0 wt% Of AI 2 O 3 and 36.0 to 57.0 wt% of TiO 2 is preferred.
  • Application Example 3 is preferred.
  • Application Example 6 and 7 and Comparative Example 4 were carried out in the same manner as in Example 1 and 2, except that, the compositions and firing temperatures of shaped ceramics were as shown in Table 3.
  • Application Example 8 was carried out in the same manner as in Example 1 and 2, except that, TiO2 powder with SiO2 coating (about 5wt%) was used instead the silica powder and the composition and firing temperature of shaped ceramics were as shown in Table 3.

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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)
  • Compositions Of Oxide Ceramics (AREA)
  • Inorganic Chemistry (AREA)

Abstract

L'invention porte sur une céramique composite de titanate d'aluminium et de magnésium qui comprend les matières premières de cuisson, telles qu'exprimées sur une base de pourcentage en poids d'oxyde, 36,0-57,0 % de TiO2 ; 41,5-62,0 % d'Al2O3 ; et 0-2,2 % de MgO, la somme totale des trois composants faisant 100 %, et 0-10 % de SiO2, pour former des filtres particulaires, avec une porosité relativement élevée, un faible coefficient de dilatation thermique (CTE) et une résistance mécanique élevée.
EP10734423A 2009-07-15 2010-07-15 Céramiques composites de titanate d'aluminium et de magnésium Withdrawn EP2454214A1 (fr)

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Publication number Priority date Publication date Assignee Title
WO2012050123A1 (fr) * 2010-10-12 2012-04-19 住友化学株式会社 Structure en nid d'abeilles de titanate d'aluminium
EP2668147A1 (fr) 2011-01-28 2013-12-04 Mann + Hummel Gmbh Corps céramique constitué d'un mélange de titanate d'aluminium
JP6041902B2 (ja) * 2012-12-27 2016-12-14 住友化学株式会社 ハニカムフィルタ及びその製造方法
JP6756530B2 (ja) * 2016-07-05 2020-09-16 イビデン株式会社 ハニカム構造体及びハニカム構造体の製造方法
ES2687800B1 (es) 2017-03-27 2019-08-06 Torrecid Sa Composicion y conformado de material ceramico de bajo coeficiente de dilatacion termica y elevada resistencia al choque termico
CN111675532A (zh) * 2020-05-29 2020-09-18 秦皇岛松浦工业炉有限公司 一种陶瓷保温炉制造工艺

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS573767A (en) * 1980-06-04 1982-01-09 Nippon Toki Kk High temperature-stable high strength aluminium titanate sintered body
JP2828986B2 (ja) * 1988-03-31 1998-11-25 株式会社東芝 セラミックス焼結体
EP0463437B2 (fr) 1990-06-22 1998-12-02 Bayer Ag Corps fritté moulé à base de titanate d'aluminium, procédé de fabrication et utilisation
JPH04305054A (ja) * 1991-03-29 1992-10-28 Ngk Insulators Ltd アルミニウムチタネート構造体とその製造方法
JP3388310B2 (ja) * 1997-08-18 2003-03-17 勉 福田 チタン酸アルミニウム粉体及びチタン酸アルミニウム焼結体の製造方法
CN1233594C (zh) * 2001-12-20 2005-12-28 罗海甦 一种型煤结合还原剂陶瓷煅烧方法
JP3489030B1 (ja) * 2002-04-26 2004-01-19 勉 福田 チタン酸アルミニウム系焼結体の製造方法
CN100427432C (zh) * 2002-11-01 2008-10-22 王世来股份有限公司 制备钛酸铝镁烧结体的方法
FR2857009A1 (fr) * 2003-04-16 2005-01-07 Sicat Materiau ceramique a base de carbure de silicium pour utilisation dans des milieux agressifs
CN100336774C (zh) * 2004-10-18 2007-09-12 成都理工大学 一种合成热稳定性钛酸铝的工艺
CN101861288B (zh) * 2007-11-14 2013-05-22 日立金属株式会社 钛酸铝质陶瓷蜂窝状结构体、其制造方法及用于制造其的原料粉末
WO2009093560A1 (fr) * 2008-01-21 2009-07-30 Sumitomo Chemical Company, Limited Céramique composite d'alumine-titanate d'aluminium-magnésium
JPWO2009122535A1 (ja) * 2008-03-31 2011-07-28 イビデン株式会社 ハニカム構造体の製造方法
US20110124484A1 (en) * 2008-06-18 2011-05-26 Sumitomo Chemical Company, Limited Process for producing aluminum titanate-based ceramics
JP2010132527A (ja) * 2008-11-07 2010-06-17 Sumitomo Chemical Co Ltd チタン酸アルミニウム系セラミックスの製造方法
JP2010155728A (ja) * 2008-12-26 2010-07-15 Sumitomo Chemical Co Ltd チタン酸アルミニウム系セラミックス焼結体の製造方法およびチタン酸アルミニウム系セラミックス焼結体

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2011008938A1 *

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