[go: up one dir, main page]

WO1998001405A1 - Compositions de ceramique - Google Patents

Compositions de ceramique Download PDF

Info

Publication number
WO1998001405A1
WO1998001405A1 PCT/GB1997/001706 GB9701706W WO9801405A1 WO 1998001405 A1 WO1998001405 A1 WO 1998001405A1 GB 9701706 W GB9701706 W GB 9701706W WO 9801405 A1 WO9801405 A1 WO 9801405A1
Authority
WO
WIPO (PCT)
Prior art keywords
weight
oxide
ceramic composition
zirconium
composition according
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.)
Ceased
Application number
PCT/GB1997/001706
Other languages
English (en)
Inventor
Kassim Juma
Sumihiko Kurita
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.)
Foseco International Ltd
Koransha Co Ltd
Original Assignee
Foseco International Ltd
Koransha Co Ltd
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 Foseco International Ltd, Koransha Co Ltd filed Critical Foseco International Ltd
Priority to EP97932897A priority Critical patent/EP0909263A1/fr
Priority to BR9710180-0A priority patent/BR9710180A/pt
Priority to AU36265/97A priority patent/AU732774B2/en
Priority to JP50489298A priority patent/JP2001505176A/ja
Publication of WO1998001405A1 publication Critical patent/WO1998001405A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

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
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/58—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides
    • C04B35/5805—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on borides
    • C04B35/58064—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on borides based on refractory borides
    • C04B35/58078—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on borides based on refractory borides based on zirconium or hafnium borides
    • 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
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/58—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides
    • 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
    • C04B35/013—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 containing carbon
    • 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
    • C04B35/10—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 aluminium oxide
    • C04B35/111—Fine ceramics
    • C04B35/117—Composites
    • 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
    • C04B35/48—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 zirconium or hafnium oxides, zirconates, zircon or hafnates
    • C04B35/486—Fine ceramics
    • C04B35/488—Composites
    • 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
    • C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
    • C04B35/58—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides
    • C04B35/583—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides based on boron nitride
    • 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
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/632—Organic additives
    • C04B35/634—Polymers
    • C04B35/63448—Polymers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • C04B35/63472—Condensation polymers of aldehydes or ketones
    • C04B35/63476—Phenol-formaldehyde condensation polymers
    • 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
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/632—Organic additives
    • C04B35/634—Polymers
    • C04B35/63448—Polymers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • C04B35/63472—Condensation polymers of aldehydes or ketones
    • C04B35/6348—Melamine-formaldehyde condensation polymers
    • 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
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/632—Organic additives
    • C04B35/634—Polymers
    • C04B35/63448—Polymers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • C04B35/63472—Condensation polymers of aldehydes or ketones
    • C04B35/63484—Urea-formaldehyde condensation polymers
    • 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
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/632—Organic additives
    • C04B35/634—Polymers
    • C04B35/63496—Bituminous materials, e.g. tar, pitch
    • 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
    • C04B35/66—Monolithic refractories or refractory mortars, including those whether or not containing clay
    • 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
    • C04B2235/32—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
    • 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
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
    • C04B2235/3244—Zirconium oxides, zirconates, hafnium oxides, hafnates, or oxide-forming salts thereof
    • 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
    • C04B2235/38—Non-oxide ceramic constituents or additives
    • 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
    • C04B2235/38—Non-oxide ceramic constituents or additives
    • C04B2235/3817—Carbides
    • C04B2235/3826—Silicon carbides
    • 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
    • C04B2235/38—Non-oxide ceramic constituents or additives
    • C04B2235/3852—Nitrides, e.g. oxynitrides, carbonitrides, oxycarbonitrides, lithium nitride, magnesium nitride
    • C04B2235/386—Boron nitrides
    • 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
    • C04B2235/42—Non metallic elements added as constituents or additives, e.g. sulfur, phosphor, selenium or tellurium
    • C04B2235/422—Carbon

Definitions

  • This invention relates to ceramic compositions which are of particular value in the handling and casting of high melting temperature metals such as iron or steel.
  • carbon bonded ceramics also known as black refractories
  • examples of such articles are pouring nozzles for molten metal-containing vessels such as ladles or tundishes, and shrouds which surround the metal stream flowing from one vessel to another.
  • These carbon bonded ceramics are formed from a mixture of graphite, one or more oxides such as alumina, magnesia and zirconia, and a binder such as a phenolic resin or pitch which will decompose to produce a carbon bond.
  • the above carbon bonded ceramic materials suffer from a number of disadvantages. They have poor thermal shock resistance and tend to crack, so that it is necessary to treat articles such as nozzles and shrouds in some way so as to minimise the thermal shock produced when the articles are heated rapidly to elevated temperatures.
  • the materials also have low oxidation resistance as they contain a relatively high proportion of carbon, mainly in the form of graphite.
  • the materials also suffer from additional disadvantages in specific applications.
  • the outer surface of a nozzle is susceptible to attack by slag present on the surface of the molten metal in which the nozzle is immersed (known as slag line attack), and the bore of a nozzle tends to become clogged in use due to the build up of alumina, when casting aluminium killed steel.
  • a carbon bonded ceramic material consisting of a mixture of boron nitride, zirconium diboride and at least one other refractory material, is particularly useful as an alternative to conventional graphite-containing carbon bonded ceramics for the production of articles used for the handling and casting of molten metals such as steel
  • a ceramic composition comprising a mixture of particles of boron nitride, zirconium diboride and at least one other refractory material bonded together by carbon produced by the decomposition of an organic binder
  • the other refractory material may be for example a refractory metal, an oxide, a carbide, a bo ⁇ de or a nitride
  • the refractory metal may be for example boron
  • Suitable refractory oxides include aluminium oxide, zirconium oxide, magnesium oxide, yttrium oxide, calcium oxide, chromium oxide and silicon oxide More than one oxide may be used, and the oxide may be a mixed refractory oxide such as mullite
  • suitable carbides include silicon carbide, boron carbide, aluminium carbide and zirconium carbide More than one carbide may be used
  • bo ⁇ des include titanium diboride and calcium hexabo ⁇ de
  • suitable nitrides include silicon nitride, aluminium nitride, titanium nitride, zirconium nitride and sialon More than one bo ⁇ de and more than one nitride may be used
  • the ceramic composition comprises a mixture of boron nitride, zirconium diboride and zirconium oxide, and the ceramic composition preferably contains 5 - 70 % by weight of boron nitride more preferably 15 - 50 % by weight, 5 - 60 % by weight of zirconium diboride, more preferably 15 - 50 % by weight, and 5 - 80 % by weight of zirconium oxide, more preferably 10 - 60 % by weight
  • the ceramic composition comprises a mixture of boron nitride, zirconium diboride and aluminium oxide, and the ceramic composition preferably contains 5 - 70 % by weight of boron nitride, more preferably 15 - 50 % by weight, 5 - 60 % by weight of zirconium diboride, more preferably 15 - 50 % by weight, and 10 - 70 % by weight of aluminium oxide, more preferably 15 - 60 % by weight
  • the proportion of each of the components of the ceramic composition is expressed as percentage by weight based on the total weight of the ceramic composition, excluding the carbon bond
  • the organic binder which decomposes to produce a carbon bond may be for example a phenol-formaldehyde resin such as a novolac or a resol phenol-formaldehyde resin, a urea-formaldehyde resin a melamine-formaldehyde resin, an epoxy resin, a furane resin or pitch
  • the organic binder is preferably a phenol-formaldehyde resin, and it is preferred that the resin is used in the form of a liquid
  • a powdered phenolic resin can be used but it is necessary to dissolve the resin in a suitable solvent, such as furfural, in order to mix the resin with the other components and produce the ceramic composition
  • the amount of liquid phenolic resin used will usually be of the order 5 - 25%, preferably 10 - 15% by weight, based on the total of the other components, and after production of the ceramic composition, the composition will usually contain 2 - 12% by weight, preferably of the order of 5% by weight, of carbon produced by decomposition of the resin, based on the total weight of the ceramic composition
  • the ceramic compositions of the invention may be produced by first mixing together particles of the boron nitride, the zirconium diboride and the other refractory material , and then adding the liquid resin and mixing until the mixture of the particles and the resin is homogeneous It may be necessary to heat the mixture
  • the ceramic compositions of the invention may be used for other applications, for example in the melting and handling of glass or in the melting, handling and casting of relatively low melting temperature metals such as aluminium and its alloys, the compositions are particularly useful for use in the handling and casting of high melting temperature metals such as iron or steel
  • each of the three components of the ceramic compositions of the invention confers particular properties on the compositions
  • the boron nitride makes the compositions non-wetting in the presence of molten steel or molten slag, and hence when used for example in a composition which is used for a casting nozzle will prevent clogging of the nozzle due to alumina build up
  • the boron nitride makes the compositions resistant to thermal shock, and helps to protect the compositions from oxidation
  • the zirconium diboride confers erosion resistance, gives protection against oxidation at higher temperatures ( up to about 1250° C) than does the boron nitride, and improves the resistance of the compositions to attack by molten slag.
  • both the aluminium oxide and the zirconium oxide improve the resistance of the composition to attack by molten steel
  • Examples of applications for the ceramic compositions of the invention in the handling and casting of steel are lining materials, and nozzles and shrouds, such as those used in continuous casting
  • the zirconium oxide-containing composition described above is particularly suitable for forming that part of a nozzle which in use is at the boundary between the surface of molten steel and molten slag which lies on top of the steel
  • the aluminium oxide-containing composition described above is particularly suitable for forming the inside of a nozzle, since it can readily be co-pressed with an alumina-graphite material which forms the rest of the nozzle, and it prevents build up of alumina and clogging of the nozzle
  • compositions may be used to form the whole nozzle if desired, it is preferred to use them only to form portions of the nozzles as described
  • the remainder of the nozzles can then be formed from a conventional carbon bonded ceramic material such as a carbon bonded alumina and graphite mixture
  • compositions were prepared as in Table 1 below The amount of each of the refractory components is expressed as percentage by weight based on the total, and the amount of liquid resin is expressed as percentage by weight of the total of the refractory components Table 1
  • Ceramic compositions according to the invention were produced by first mixing together particulate boron nitride, particulate zirconium diboride and, if present particulate aluminium oxide, zirconium oxide and silicon carbide in an intensive mixer and then adding a liquid phenol-formaldehyde resin, and mixing until the mixture of the particles and the resin was homogeneous
  • the boron nitride was a refractory grade containing up to 7% by weight of oxygen and had a particle size of less than 10 microns, and the zirconium diboride had a particle size of less than 45 microns
  • the aluminium oxide and zirconium oxide Were both 50/50 w/w of particles of less than 500 microns and particles of less than 53 microns
  • the silicon carbide had a particle size of less than 150 microns
  • the resin was a liquid novolac phenol-formaldehyde resin having a solids content of 60% by weight
  • the mixture of particles and liquid resin was heated to reduce the liquid content of the resin to render the mixture suitable for forming
  • the mixture was then formed into test specimens by cold isostatic pressing of the mixture in a mould After forming the specimens were stripped from the mould, and heated for 1 hour at 200° C heated to cure and cross-link the resin. Finally the test specimens were heated at 900° C to pyrolyse the resin and produce a carbon bond.
  • compositions 1 , 2, 3, and 4 from Example 1 were tested to assess their resistance to molten steel in comparison with a conventional carbon bonded alumina-graphite material, by measuring their corrosion rate when immersed in molten steel at 1650° C
  • Rods 50 mm in diameter and 300 mm in length were made by isostatic pressing using the method described in Example 1 , and their diameter was accurately measured The rods were then held in jigs, and immersed for one hour in molten steel in an induction furnace At the end of the test the diameter of the rods was remeasured
  • compositions 6, 7, and 8 from Example 1 were tested to assess their resistance to molten slag in comparison with a carbon bonded zirconia graphite material, by measuring their corrosion rate when immersed in molten slag at 1580° C
  • Rods of the same dimensions as those in Example 1 were made using the method described in Example 1 , and their diameter was accurately measured A borosilicate glass was sprinkled on to the surface of molten steel in an induction furnace, and allowed to melt to form a slag The rods were then held in jigs and immersed in the molten steel for one hour At the end of the test the diameter of the rods was remeasured in the area which had been in contact with the molten slag
  • Example 1 All eight compositions from Example 1 were tested to assess their resistance to oxidation, by measuring their oxidation rate at 1200° C at various time intervals Disc shaped specimens 30 mm in diameter and 10 mm high were made by the method described in Example 1. The specimens were weighed and placed in an electric oven for various times, and then removed, cooled and reweighed.
  • Compositions 1 and 3 were tested in comparison with a conventional carbon bonded alumina-graphite material to assess their ability to suppress clogging due to alumina build up when used to form the inside surface of a nozzle though which molten steel is cast.
  • Tubular nozzles having an outside diameter of 50 mm, an inside diameter of 15 mm and a length of 300m were made using the method described in Example 1
  • the nozzles were immersed in aluminium killed steel having an aluminium content of 0 2% by weight After immersion of the nozzles, oxygen was bubbled into the steel and the nozzles were agitated continuously to distribute the oxygen After 30 minutes the tests were concluded and the nozzles were removed The nozzles were then sectioned and inspected to assess the build up of alumina
  • composition 3 showed no clogging, and while composition 1 did show some clogging the material was considerably better than the alumina-graphite material
  • Example 5 Four compositions were prepared as in Table 5 below using the method described in Example 1
  • the boron nitride, zirconium diboride, aluminium oxide and zirconium oxide which were used were the same as those which were used in Example 1
  • the titanium diboride, boron and calcium hexabo ⁇ de were powders of particle size less than 50 microns
  • the magnesium oxide had a particle size of 53 to 500 microns
  • the amount of each component is expressed in the same manner as in Example 1
  • compositions were tested to assess their resistance to molten slag using the method described in Example 3. and they were tested to assess their resistance to oxidation using the method described in Example 4.
  • a mixture was prepared having the following composition by weight -
  • the mixture of the ceramic components was mixed with 6 5 % by weight, based on the total weight of the four ceramic components, of a liquid novolac phenol-formaldehyde resin having a solids content of 60 % by weight as described in Example 1
  • a slag containing 7 % by weight of fluoride was melted on top of molten steel held at 1650 °C in a 250 kg capacity high frequency induction heating furnace
  • the rods were then held in jigs, and tested by immersing them in the molten steel for two hours to assess their resistance to thermal shock, the degree of penetration of molten steel and slag, and the rate of corrosion at the slag/metal interface Similar rods made from a carbon bonded zirco ⁇ ia-graphite material were tested in a similar manner Both types of rod had adequate thermal shock resistance and resistance to penetration, but the rods made from the composition according to the invention was superior in terms of its rate of corrosion at the slag/metal interface
  • the carbon bonded zirconia-graphite rods had a corrosion rate of 3 05 mm per hour at the slag line whereas the rods made form the composition according to the invention had a corrosion rate of only 0 95 mm per hour
  • a mixture was prepared having the following composition by weight -
  • the mixture of the ceramic components was mixed with 7 5 % by weight, based on the total weight of the three ceramic components, of a liquid novalac phenol-formaldehyde resin having a solids content of 60 % by weight as described in Example 1
  • the rods were then held in jigs and immersed in aluminium killed steel containing 0 05 to 0 1 % by weight aluminium in a 250 kg capacity high frequency induction heating furnace
  • aluminium killed steel containing 0 05 to 0 1 % by weight aluminium in a 250 kg capacity high frequency induction heating furnace
  • the surface of the molten steel was covered with a layer of rice husks, and in order to prevent excessive oxidation of the steel during the test argon gas was also used to protect the surface of the steel
  • the temperature of the molten steel was 1570 to

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Organic Chemistry (AREA)
  • Structural Engineering (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Composite Materials (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Ceramic Products (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)

Abstract

Compositions de céramique particulièrement utiles pour la manipulation ou le coulage de l'acier, par exemple, en tant que matériaux de doublure ou afin de produire des ajutages ou des enveloppes de protection utilisées en coulage continu. Ces compositions comprennent un mélange de particules de nitrure de bore, de diborure de zirconium et, au moins, un autre matériau réfractaire, liés par du carbone produit par la décomposition d'un liant organique, tel qu'une résine ou de la poix. L'autre matériau réfractaire peut être, par exemple, un métal réfractaire, un oxyde, un carbure, un borure ou un nitrure. Les compositions contenant de l'oxyde de zirconium, à raison de 5-70 % en poids de nitrure de bore, 5-60 % en poids de diborure de zirconium et 5-80 % en poids d'oxyde de zirconium, sont particulièrement appropriées pour constituer au moins la partie d'un ajutage mis en application au niveau du conduit de scories dans une cuve d'acier en fusion. Les compositions contenant de l'oxyde d'aluminium, à raison de 5-70 % en poids de nitrure de bore, 15-50 % en poids de diborure de zirconium et 10-70 % en poids d'oxyde d'aluminium, sont particulièrement appropriées pour constituer l'intérieur d'ajutages, étant donné qu'elles résistent à l'accumulation d'alumine et empêchent l'obturation des ajutages.
PCT/GB1997/001706 1996-07-05 1997-06-24 Compositions de ceramique Ceased WO1998001405A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP97932897A EP0909263A1 (fr) 1996-07-05 1997-06-24 Compositions de ceramique
BR9710180-0A BR9710180A (pt) 1996-07-05 1997-06-24 Composiçãom cerâmica.
AU36265/97A AU732774B2 (en) 1996-07-05 1997-06-24 Ceramic compositions
JP50489298A JP2001505176A (ja) 1996-07-05 1997-06-24 セラミック組成物

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB9614188.2A GB9614188D0 (en) 1996-07-05 1996-07-05 Ceramic compositions
GB9614188.2 1996-07-05

Related Child Applications (2)

Application Number Title Priority Date Filing Date
US09214128 A-371-Of-International 1999-01-11
US09/867,534 Continuation US20010036894A1 (en) 1996-07-05 2001-05-31 Ceramic compositions

Publications (1)

Publication Number Publication Date
WO1998001405A1 true WO1998001405A1 (fr) 1998-01-15

Family

ID=10796447

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1997/001706 Ceased WO1998001405A1 (fr) 1996-07-05 1997-06-24 Compositions de ceramique

Country Status (12)

Country Link
EP (1) EP0909263A1 (fr)
JP (1) JP2001505176A (fr)
KR (1) KR20000023576A (fr)
AR (1) AR003100A1 (fr)
AU (1) AU732774B2 (fr)
BR (1) BR9710180A (fr)
CA (1) CA2260197A1 (fr)
GB (1) GB9614188D0 (fr)
TR (1) TR199802768T2 (fr)
TW (1) TW436471B (fr)
WO (1) WO1998001405A1 (fr)
ZA (1) ZA975895B (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2030959A1 (fr) * 2007-08-28 2009-03-04 ESK Ceramics GmbH & Co.KG Matières premières composites polycristallines frittées à base de bornitride et de dioxyde de zirconium, leur procédé de fabrication et leur utilisation
CN104211411A (zh) * 2014-06-19 2014-12-17 江苏泰瑞耐火有限公司 ZrO2-BN陶瓷材料浸入式水口及其制备方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102156575B1 (ko) * 2020-01-23 2020-09-17 주식회사 화인테크 저열팽창 계수를 갖는 머시너블 세라믹 복합체 및 이의 제조방법

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62288171A (ja) * 1986-06-06 1987-12-15 旭硝子株式会社 ＺｒＢ↓２質複合焼結体
JPS63100071A (ja) * 1986-10-16 1988-05-02 黒崎窯業株式会社 ＺｒＢ↓２含有耐火物の製造方法
JPH03291144A (ja) * 1990-04-07 1991-12-20 Nippon Steel Corp 急冷金属薄帯製造用ノズル

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62288171A (ja) * 1986-06-06 1987-12-15 旭硝子株式会社 ＺｒＢ↓２質複合焼結体
JPS63100071A (ja) * 1986-10-16 1988-05-02 黒崎窯業株式会社 ＺｒＢ↓２含有耐火物の製造方法
JPH03291144A (ja) * 1990-04-07 1991-12-20 Nippon Steel Corp 急冷金属薄帯製造用ノズル

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
CHEMICAL ABSTRACTS, vol. 109, no. 8, 22 August 1988, Columbus, Ohio, US; abstract no. 60210, N. KAJI ETAL.: "Zirconium diboride-containing refractory materials resistant to molten metal and slag" XP002041552 *
CHEMICAL ABSTRACTS, vol. 110, no. 4, 23 January 1989, Columbus, Ohio, US; abstract no. 28146, M. SEGAWA ET AL.: "Zirconium diboride-type composite ceramics" XP002041553 *
CHEMICAL ABSTRACTS, vol. 116, no. 16, 20 April 1992, Columbus, Ohio, US; abstract no. 157445, J. TANAKA ET AL.: "Nozzles for the continuous casting of thin metal strips" XP002041554 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2030959A1 (fr) * 2007-08-28 2009-03-04 ESK Ceramics GmbH & Co.KG Matières premières composites polycristallines frittées à base de bornitride et de dioxyde de zirconium, leur procédé de fabrication et leur utilisation
WO2009030331A1 (fr) * 2007-08-28 2009-03-12 Esk Ceramics Gmbh & Co. Kg Matériaux composites polycristallins frittés à base de nitrure de bore et de dioxyde de zirconium, leur procédé de production et leur utilisation
CN104211411A (zh) * 2014-06-19 2014-12-17 江苏泰瑞耐火有限公司 ZrO2-BN陶瓷材料浸入式水口及其制备方法

Also Published As

Publication number Publication date
AU732774B2 (en) 2001-04-26
KR20000023576A (ko) 2000-04-25
ZA975895B (en) 1998-01-30
GB9614188D0 (en) 1996-09-04
EP0909263A1 (fr) 1999-04-21
TR199802768T2 (xx) 1999-03-22
AR003100A1 (es) 1998-07-08
TW436471B (en) 2001-05-28
JP2001505176A (ja) 2001-04-17
AU3626597A (en) 1998-02-02
CA2260197A1 (fr) 1998-01-15
BR9710180A (pt) 2000-01-11

Similar Documents

Publication Publication Date Title
EP0309225A2 (fr) Prévention de Al2O3-formation dans des basettes de coulée et dispositifs similaires
PL189510B1 (pl) Kompozycja do formowania tulei na poziomie żużla,kształtka wylewowa do wylewania stopionego metalu, oraz sposób jej otrzymywania
JPH11506393A (ja) 鋳造装置の中の溶融金属流出装置と使用方法
JPS62297264A (ja) 炭素結合した耐火物
JP4132212B2 (ja) 耐食性に優れるジルコニア−黒鉛質耐火物及びそれを用いた連続鋳造用ノズル
JP5166302B2 (ja) 連続鋳造用ノズル
US20010036894A1 (en) Ceramic compositions
AU732774B2 (en) Ceramic compositions
JPS6348828B2 (fr)
KR20250126727A (ko) 내화성 재료, 내화성 재료를 제조하는 방법 및 그의 용도
JP4118058B2 (ja) 鋳造用浸漬ノズル
JP3312373B2 (ja) 連続鋳造用ロングノズル
JPH0617268B2 (ja) 連続鋳造用耐火物
US5975382A (en) Continuous casting nozzle for casting molten steel
MXPA98010883A (en) Ceram compositions
JP2810111B2 (ja) ガス吹込耐火物
JPH0556306B2 (fr)
KR100349243B1 (ko) 연속주조용 침지노즐
JPS6152099B2 (fr)
JPH11246265A (ja) 高耐食性溶融シリカ含有耐火物
JPS63157746A (ja) 連続鋳造用浸漬ノズル
JP4020224B2 (ja) 溶融金属処理用部材
JPH05148006A (ja) 炭素含有耐火物
JPS63123860A (ja) 溶鋼鋳造用ノズル
JPS5911548B2 (ja) 連続鋳造用浸漬ノズル

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 97196168.9

Country of ref document: CN

AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG US UZ VN AM AZ BY KG KZ MD RU TJ TM

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH KE LS MW SD SZ UG ZW AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 1997932897

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: PA/a/1998/010883

Country of ref document: MX

ENP Entry into the national phase

Ref document number: 1998 504892

Country of ref document: JP

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 2260197

Country of ref document: CA

Ref document number: 2260197

Country of ref document: CA

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 1998/02768

Country of ref document: TR

WWE Wipo information: entry into national phase

Ref document number: 1019997000021

Country of ref document: KR

WWE Wipo information: entry into national phase

Ref document number: 09214128

Country of ref document: US

WWP Wipo information: published in national office

Ref document number: 1997932897

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

WWP Wipo information: published in national office

Ref document number: 1019997000021

Country of ref document: KR

WWR Wipo information: refused in national office

Ref document number: 1997932897

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1019997000021

Country of ref document: KR

WWW Wipo information: withdrawn in national office

Ref document number: 1997932897

Country of ref document: EP