EP0680521B1 - Metaux ferreux coules, en particulier pour cylindres de laminage - Google Patents

Metaux ferreux coules, en particulier pour cylindres de laminage Download PDF

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Publication number
EP0680521B1
EP0680521B1 EP94900231A EP94900231A EP0680521B1 EP 0680521 B1 EP0680521 B1 EP 0680521B1 EP 94900231 A EP94900231 A EP 94900231A EP 94900231 A EP94900231 A EP 94900231A EP 0680521 B1 EP0680521 B1 EP 0680521B1
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EP
European Patent Office
Prior art keywords
alloy
steel
carbide particles
iron
metal
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EP94900231A
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German (de)
English (en)
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EP0680521A1 (fr
Inventor
David Wragg
Paul Herbert Hewitt
Jack Nutting
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Sheffield Forgemasters Ltd
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Sheffield Forgemasters Ltd
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Priority claimed from GB929224271A external-priority patent/GB9224271D0/en
Priority claimed from GB939315356A external-priority patent/GB9315356D0/en
Application filed by Sheffield Forgemasters Ltd filed Critical Sheffield Forgemasters Ltd
Publication of EP0680521A1 publication Critical patent/EP0680521A1/fr
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
    • C22C32/001—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides
    • C22C32/0015—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides with only single oxides as main non-metallic constituents
    • C22C32/0026—Matrix based on Ni, Co, Cr or alloys thereof
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/10—Alloys containing non-metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D23/00—Casting processes not provided for in groups B22D1/00 - B22D21/00
    • B22D23/06—Melting-down metal, e.g. metal particles, in the mould
    • B22D23/10—Electroslag casting
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/17—Metallic particles coated with metal
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0006—Adding metallic additives
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
    • C22B9/16—Remelting metals
    • C22B9/18—Electroslag remelting
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/05—Mixtures of metal powder with non-metallic powder
    • C22C1/051—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor
    • C22C1/053—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds
    • C22C1/055—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds using carbon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/10—Alloys containing non-metals
    • C22C1/1036—Alloys containing non-metals starting from a melt
    • C22C1/1068—Making hard metals based on borides, carbides, nitrides, oxides or silicides

Definitions

  • This invention relates to cast iron or steel, herein defined as "engineering ferrous metals”. More particularly, this invention relates to a rolling mill roll comprising cast iron or steel.
  • US-A-5,023,145 discloses an alloy having a substantially uniform distribution of three carbide aggregates in which a uniform distribution of the three carbides is achieved by using a relatively heavier binder material with a relatively lighter carbide rendering the resultant aggregates relatively similar in density.
  • EP-A-0386515 discloses a process for manufacture of a metallic compound body using an electro slag refining process in the course of which solid alloy-carbide particles in the form of tungsten carbide are added to the melt.
  • WO 91/16466 discloses an iron based alloy having dispersed therein tungsten carbide particles.
  • WO 93/03192 discloses adding, to an iron based melt, iron-coated alloy carbide particles (WTiC) of matching density (7 to 7.9g/cm 3 .
  • An object of the invention is to provide a new and improved method of making an engineering ferrous metal whereby the above mentioned problems are overcome or are reduced and a further object of the invention is to provide a new and improved engineering ferrous metal product having a desired carbide content which is not limited by thermo-dynamic considerations.
  • wetting we mean the ability of the liquid engineering ferrous metal to wet the coating metal. More particularly, for example, where the interfacial tension between the liquid engineering ferrous metal and the solid coating metal is such that the contact angle there between is 0° - 90°.
  • a density which matches we mean a density lying in the range 6-8 gms per cc. This is to be compared with a typical density of 7 gms per cc. for cast iron and steel. More preferably, the alloy carbide particles have a density of ⁇ 5% of the density of the engineering ferrous metal to which they are added.
  • the weltability of the coated particles and the density of the alloy carbide particles each promote a uniform distribution of the carbide particles in the liquid engineering ferrous metal which is retained when the metal solidifies.
  • uniform distribution we mean an even distribution throughout the section of a casting made of the engineering ferrous metal with no significant segregation.
  • the solid carbide particles are not orientated in any direction and are distributed across all phases of the micro-structure.
  • the coating metal preferably comprises iron or an iron carbon alloy, but may comprise an alloy of two or more elements selected from the group comprising iron, nickel, copper, titanium and carbon, or may be nickel or copper and usual incidentals.
  • the coating metal may comprise nitrogen, for example up to about 0.1% nitrogen.
  • the coating is iron, then because iron has a higher melting point than the engineering ferrous metal to which it is to be added, which would inhibit wettability, it is preferred to add an appropriate amount of at least one alloying element such as carbon, nickel, copper or titanium to the iron to produce an alloy having a melting point which matches the operating temperature of the ferrous metal.
  • alloying element such as carbon, nickel, copper or titanium
  • operating temperature is defined herein as the temperature of the engineering ferrous metal at which the coated carbide particles are added.
  • the iron coating may contain up to 3.5% carbon.
  • the coated alloy carbide particles may be added to the engineering ferrous metal and permitted to dwell therein sufficiently long for carbon from the engineering ferrous metal to diffuse into the coating and so produce a composition which has a melting point which matches the operating temperature of engineering ferrous metal.
  • the carbide particles have a matching density as described above when the particles are left in the molten engineering ferrous metal for a dwell time long enough for carbon to diffuse into the coating to cause the melting points to match.
  • the composition of the coating metal may be such as to provide a melting point which is more than 30°C below the operating temperature of the engineering ferrous metal to which the coated particles are added.
  • the coated alloy carbide particles may be added to the liquid engineering ferrous metal either in the melting furnace or in a ladle into which the metal has been poured from the melting furnace, or in the stream of metal being poured from the melting furnace to the ladle, or in the stream of metal being poured from the ladle into a mould.
  • the coated alloy carbide particles in the melting furnace so as to maximise the dwell time of the alloy carbide particles in the ferrous metal prior to the onset of solidification.
  • the melting furnace is an induction furnace, since an induction furnace provides good stirring of the melt.
  • titanium of the carbide oxidises to form titanium oxide which can react with silicon from the furnace lining to form a hard crust on the metal surface which may entrap the carbide particles and reduce their distribution in the molten metal.
  • the coated alloy carbide particles may be added to the ferrous engineering metal melt in the form of a powder comprising powder particles having a particle size up to 2mm and preferably of about 500 micro-meters (microns) and containing alloy carbide particles having a particle size of up to 10 micro-meters (microns) and preferably in the range 1-5 micro-meters (microns) and more preferably 2-5 micro-meters (microns).
  • a powder comprising powder particles having a particle size up to 2mm and preferably of about 500 micro-meters (microns) and containing alloy carbide particles having a particle size of up to 10 micro-meters (microns) and preferably in the range 1-5 micro-meters (microns) and more preferably 2-5 micro-meters (microns).
  • the powder particles may comprise:- 25% coating metal. 30% Ti 35% W Balance Carbon (including up to 3.5% free carbon) and usual incidentals.
  • the coating metal may comprise iron such as alpha iron and may comprise wholly or substantially wholly alpha iron and up to 3.5% free carbon.
  • Such a coating metal has a melting point of about 1520°C and hence the powder is suitable for adding to engineering ferrous metal having an operating temperature of about 1500°C or above.
  • the coating metal may comprise an alloy of iron, nickel and carbon.
  • the powder and alloy carbide particles may be of the same size as mentioned above and the powder particles may comprise:- 27% coating metal. 30% Ti 35% W Balance Carbon (including up to 0.5% free carbon) and usual incidentals.
  • the coating material may comprise an alloy of iron, nickel and carbon: 59% nickel 41% iron and up to 0.5% free carbon and usual incidentals.
  • Such a coating metal has a melting point of about 1420°C and is particularly suitable for adding to engineering ferrous metals having an operating temperature of below about 1500°C.
  • the coating metal may be an alloy of either iron, nickel and copper or iron and copper with or without carbon in each case to provide a lower melting point.
  • the coating metal contains significant amounts of carbon, for example, 2 - 3.5%
  • carbon content of the powder is preferably reduced to less than about 0.5% in order to minimise the softening effect.
  • the coating metal contains nickel a similar softening effect can occur even though the coating metal has relatively low carbon, e.g. 0.5%. This softening effect can be overcome or reduced by adjusting the chemical composition of the engineering ferrous metal.
  • coated alloy carbide particles may he added during an electroslag remelting operation.
  • the microstructure may comprise matrix and carbide which have resulted from phase transformation of the engineering ferrous metal; said carbide being referred to herein, as mentioned hereinbefore, as "transformation carbide”.
  • the discrete alloy carbide particles preferably have a higher hardness than the transformation carbide present in the microstructure.
  • the discrete alloy carbide particles may increase the hardness of the engineering ferrous metal by virtue of the law of mixtures and/or the phase transformation of the engineering ferrous metal may be modified and enhanced by the presence of the discrete alloy carbide particles.
  • the discrete alloy carbide particles may be distributed in the matrix and/or the transformation carbide.
  • the discrete alloy carbide particles may be uniformly distributed in the microstructure.
  • the alloy carbide particles may have a hardness of about 3,000 vpn.
  • the alloy carbide is preferably selected from the group comprising chromium, molybdenum, titanium, tungsten, niobium, vanadium or mixed carbides thereof such as Cr 7 C 3 , (CrMo) 7 C 3 or mixed carbo-nitrides.
  • the carbide may be a mixed tungsten titanium carbide of the kind (TiW)C where the ratio of titanium to tungsten is about 1:1 by weight.
  • the alloy carbide may comprise Ti and W in the ratio range: 1:1 to 1:1.17
  • the alloy carbide may contain nitrogen, for example up to about 0.1% nitrogen.
  • the alloy carbide preferably comprises:- 42% Ti 49% W 9% C ans usual residuals
  • the alloy carbide may contain up to 0.1% nitrogen.
  • the alloy carbide particles have a very low co-efficient of thermal expansion compared to the co-efficient of thermal expansion of engineering ferrous metals. Accordingly, if relatively large alloy carbide particles were present in the engineering ferrous metals this would give rise to high stresses on cooling, causing dislocations to form, and leading to thermal fatigue.
  • the alloy carbide particles preferably have a maximum dimension of up to 10 microns and preferably 1-5 microns and more preferably 2-5 microns.
  • the amount of alloy carbide particles added is such as to achieve up to 20% by volume of alloy carbide particles in the solid metal.
  • the alloy carbide content may be in the range 0.1 to 20% by volume, and may be in the range 1 to 20% and more preferably 3 to 10% when a hardening effect based on the law of mixtures is provided.
  • the alloy carbide content may be lower, e.g. down, for example from about 1%, to about 0.5% or 0.1% or less when a hardening effect based on a modification of the transformation of the microstructure is provided.
  • the engineering ferrous metal preferably has a carbon content lying in the range 0.3 - 3.8%.
  • the engineering ferrous metals may contain chromium and may have a chromium content which is greater than or equal to 1%.
  • the engineering ferrous metal may contain nitrogen, for example up to 0.1% nitrogen.
  • coating metal, and/or the alloy carbide and/or the engineering ferrous metal contains nitrogen it is considered that titanium carbonitrides may be precipitated in the microstructure of the engineering ferrous metal.
  • the total nitrogen content of all the components may be limited to about 0.1% nitrogen.
  • the engineering ferrous metal may have a composition falling within one of the following ranges: Indefinite Chill such as: T.C. Si Mn Ni Cr Mo Cu V 3.00 0.70 0.40 3.0 0.8 0.15 0.10 up to 3.50 1.20 1.40 5.5 2.0 0.50 1.00 0.50 Chromium Irons such as: T.C. Si Mn Ni Cr Mo Cu V 2.00 0.40 0.40 0.40 10.00 0.50 0.10 0.10 3.00 2.00 1.50 1.50 20.00 3.00 2.00 0.50 0.50 High Alloy Steels such as: T.C. Si Mn Ni Cr Mo V W 0.50 0.40 0.40 0.10 5.00 0.50 0.00 0.00 1.50 0.80 1.00 1.00 15.00 5.00 5.00 5.00 Tool Steels such as: T.C.
  • Indefinite Chill such as: T.C. Si Mn Ni Cr Mo Cu V 3.00 0.70 0.40 3.0 0.8 0.15 0.10 up to 3.50 1.20 1.40 5.5 2.0 0.50 1.00 0.50
  • Chromium Irons such as: T.C. Si M
  • Such a steel may be used for the finishing stands, of a hot strip steel mill.
  • Medium Alloy Steels such as : T.C. Si Mn Ni Cr Mo V W 0.30 0.40 0.40 0.10 2.00 0.10 0.10 0.10 1.50 0.80 1.00 1.00 5.00 0.50 0.50 0.50 0.50
  • Low Alloy Steels such as: T.C. Si Mn Ni Cr Mo V W 0.30 0.40 0.40 0.10 0.10 0.10 0.10 0.10 1.50 0.80 1.00 1.00 2.00 0.50 0.50 0.50 0.50
  • S.G. Irons such as: T.C. Si Mn Ni Cr Mo Cu 2.50 0.90 0.10 0.10 0.00 0.00 0.00 3.70 3.00 1.00 5.00 1.00 2.00 2.00
  • Nitrogen for example up to 0.1%, may also be present where appropriate.
  • a rolling mill roll having at least an outer part which comprises an engineering ferrous metal according to the second aspect of the invention or an engineering ferrous metal made according to the first aspect of the invention.
  • a metal made according to the first aspect of the invention or according to the second aspect of the invention is cast to make at least an outer part of the rolling mill roll.
  • the rolling mill roll may be a composite rolling mill roll of the kind having a core and an outer shell with, optionally, at least one intermediate layer, in which the shell comprises said outer part.
  • the alloy carbide particles may be introduced into a molten engineering ferrous metal of which the shell is to be formed and then the engineering ferrous metal with the alloy carbide particles therein may be poured into a mould.
  • the carbide particles may be introduced into the mould under a protective atmosphere of inert gas such as argon, or under a vacuum.
  • the composite roll may be made by centrifugal casting.
  • a roll may be made by performing an electroslag remelting operation on a consumable electrode which comprises an inner body provided with an external cladding comprising a hollow element containing said coated alloy carbide particles.
  • the inner body may be tubular or solid.
  • the hollow element may comprise a sleeve or a plurality of discrete hollow elements such as tubes.
  • the material inside the or each hollow element may also comprise a powder alloy ingredient(s).
  • the powder of the alloy element may have a mesh size of less than 3mm, but may have a mesh size up to 5mm and may lie in the range 2 - 5mm.
  • Each hollow element or hollow sleeve may comprise steel, such as mild steel or stainless steel.
  • the cladding comprises discrete elements
  • at least one of the elements may be of different composition to the other elements.
  • the inner body may be of constant composition throughout its cross-section or it may be of varying composition across at least part of its cross-section.
  • the droplets of molten coated alloy carbide or of molten coated alloy carbide and alloy ingredient from the hollow elements because of their spatial and temperature proximity to the mould wall, solidify relatively rapidly at or adjacent to the mould wall whereby the region of the re-melted ingot adjacent the mould wall has a relatively high and uniform distribution of alloy carbide or carbide and alloy ingredient.
  • the alloy carbide particles do not wholly melt they are trapped in the melt adjacent the mould wall as it solidifies relatively rapidly.
  • the melting point of the alloy ingredient and/or of the alloy carbides may be greater than the melting point of the slag and of the inner part of the consumable electrode.
  • the outer part of the ingot may be hardened by a dispersion hardening effect of the alloy carbides.
  • the outer part of the rolled ingot may be hardened, additionally, or alternatively, by a secondary hardening heat treatment operation.
  • the electroslag remelting operation may be performed to provide a roll comprising an inner part having a first composition and a surface part having a second composition which is different from the first composition and the metal of the roll between the inner part and the surface part having a composition which changes from the first composition to the second composition without discontinuity. This may be achieved by inter-relating the voltage, and current and the slag composition of the electroslag remelting operation so that the molten bath is relatively flat.
  • the cooling rate of the mould may be adjusted as may be the rate of movement of the mould.
  • the electroslag remelting operation may he performed to provide a roll of substantially uniform composition throughout the cross-section of the roll.
  • ESR electroslag remelting
  • the roll may be a composite roll made by ESR cladding or spray cladding.
  • ESR cladding an arbor is clad using the electroslag re-melting method either utilising a wire feed as the stock material or a hollow electrode.
  • the coated particles may he introduced by a powder feed into the molten pool.
  • either a powder feed may be used, or preferably, the coated particles may be incorporated into the hollow electrode during the primary melting and casting operation in a similar way to the production of the shell metal described above.
  • the coated particles may be incorporated into a spray deposited layer. It is possible to produce a spray deposited layer hardened by the coated carbide particles of sufficient depth to provide the full working life of a rolling mill roll.
  • a roll may be made by monobloc static casting where a roll is made simply by filling a stationary mould with a single engineering ferrous metal.
  • a roll may be made by a double poured static casting method wherein a roll is made by first partly filling a mould up to the top of a barrel part of the roll with an engineering ferrous metal of a desired composition for an outer shell part of the roll, made by the method of the first aspect of the invention or according to the second aspect of the invention which is provided with carbide particles, and, when an outer part of the shell metal has solidified, a metal of a desired core composition is fed into the bottom of the mould to dilute the first metal until a predetermined amount of metal has been displaced from an overflow between the ends and generally about halfway up, an upper journal part of the mould, the overflow is then closed and filling of the mould with the second metal is completed.
  • a roll is made by casting an ingot of metal made according to the first aspect of the invention or according to the second aspect of the invention and then forging the ingot to provide a forged roll followed by heat treating the forged roll.
  • a roll according to the present invention fulfils a market demand which has hitherto not been satisfactorily met by providing a roll having greater fracture toughness and spall resistance as well as having improved wear resistance.
  • a roll embodying the present invention is intended for use in the finishing stands of hot and cold strip mills. It may be used for roughing stands in hot strip mills and for other flat rolling purposes.
  • a roll having said outer part made of the engineering ferrous metals listed below are intended for use in the respective applications specified.
  • the core may be flake, compact/vermicular or nodular cast iron, steel or other suitable material.
  • Alloy carbide particles having a density which matches the parent metal results in the alloy carbide particles being distributed evenly throughout the section of the shell and not being centrifuged to the bore.
  • Engineering ferrous metals made by a method embodying the first aspect of the invention or according to the second aspect of the invention may be usefully used in other spin casting processes, for example, for producing liners for diesel engines and pipes such as for gas or oil, or other spin cast articles. Such as hollow sleeves for use in beam mills and other sections.
  • a metal made according to the first aspect of the invention or according to the second aspect of the invention is poured into a spin casting mould and a spin casting operation is performed thereon.
  • the invention is not limited to products made by spin or centrifugal casting.
  • the invention may be applied to a wide range of engineering ferrous metals for many purposes.
  • the engineering ferrous metals can be cast into conventional ingot moulds and subsequently forged into components, for example rolling mill rolls.
  • Rolls manufactured in this way would typically be hardened to a martensitic or bainite structure and would be used for the cold rolling of steel. For these applications a uniform structure is required to impart a uniform finish to the cold rolled product.
  • an engineering ferrous metal melt comprising an indefinite chill type iron having the following composition was made in conventional manner in an induction furnace. Carbon 3.3% Silicon 0.85% Manganese 0.50% Nickel 2.3% Chromium 1.1% Molybdenum 0.1% Sulfur 0.050% Phosphorus 0.060% Iron and usual incidentals Balance
  • a powder comprising alloy carbide particles surrounded by an iron coating with a carbon content of 3.00% were added to the melt in the melting furnace in an amount equivalent to 10% weight.
  • the powder particles had a particle size of up to 500 microns and comprised:- 25% Alpha Iron 30% Ti 35% W Balance C (of which 3% was free carbon) and usual incidentals.
  • the alloy carbide particles had an average particle size of up to 10 microns and comprised a solid solution of 30% Ti and 35% W carbides and had a density of about 7 so as to match that of the iron.
  • the above mentioned operating temperature is higher than the usual temperature to which metal of the above composition is heated before tapping because the coating metal of the powder has a melting point of about 1520°C and it is desirable that the metal be as hot as possible.
  • a temperature of higher than about 1500°C is not possible because of the tendency to "whiten" the indefinite chill iron.
  • the melt was then allowed to remain in the furnace for about 15 minutes to recover its operating temperature of approximately 1500°C.
  • the molten metal was then poured into a ladle and then transferred in the ladle from the melting furnace to a conventional spin casting plant shown in Figure 1 where the metal was poured from the ladle into the spin casting plant to form a shell S of the above described metal in conventional manner.
  • a composite rolling mill roll metal of suitable composition such as nodular cast iron, would then be poured to form a core C.
  • the present example was concerned with providing a shell, i.e. a tubular product, and so the core metal was not poured.
  • the dwell time of the metal in the furnace after adding the carbide particles was about 15 minutes to allow for temperature recovery and the dwell time in the ladle before pouring into the spin casting plant was about 15 minutes. Hence, in the present example about 30 minutes elapsed after adding the carbide particles and before casting. If desired the dwell time may be longer, e.g. 1 hour or 1.5 hours or more, or may be less.
  • the added carbide particles are distributed relatively uniformly on a macroscopic scale throughout the thickness of the shell. It is particularly to be noted that the carbide particles are not segregated at grain boundaries but are distributed relatively uniformly throughout the microstructure irrespective of the phases present as a result of phase transformation during solidification and cooling. It will be also seen from Figure 7 that the microstructure is of the same nature as in a comparison base material of the same composition but without alloy carbide particle addition.
  • the duplex nature of the carbides with a dark core suggests that the outer part of the carbide is W rich, and the inner Ti rich.
  • the alloy carbide dispersion is uniform throughout the sample section and has an "area fraction" of about 5%, corresponding to a "volume fraction” of 5%. Whilst there is some evidence of clustering of the particles there are only a few particles in each cluster and the clustering is independent of the position of the particles in the engineering ferrous metal.
  • alloy carbide particles had been displaced ahead of the solidification interface, that is to say, the alloy carbide particle distribution was independent of the underlying microstructure.
  • the carbide particle size lay in the range 2 - 5 microns.
  • the hardness of the sample was tested and found to be VHN 30 810 and the hardness of a sample cut from the comparison roll was found to be VHN 30 650.
  • a composite roll comprising a shell made of Indefinite chill cast iron and a nodular cast iron core was made by a spin casting technique similar to that of Example I except that in this case a finished roll was made by pouring nodular cast iron core C after completion of the shell forming stage.
  • the shell metal had the following composition:- T.C. - 3.40 Silicon - 0.85 Magnesium - 0.51 Nickel - 4.13 Chromium - 1.63 Molybdenum 0.46 Sulfur 0.13 Phosphorus 0.35 Copper 0.06 Lead 0.0013 Vanadium 0.021 Titanium 0.175 Iron and usual incidentals Balance
  • This metal was again made in an induction furnace and the metal in the induction furnace was heated above the melting point of the metal to the normal operating temperature, which, for example, is approximately 200°C above the liquidus temperature.
  • the liquidus temperature was 1215°C and the operating temperature was 1460°C.
  • the induction furnace was provided with a cover and argon was fed into the interior of the cover but may be injected into the melt.
  • the induction coil was turned off.
  • the powder of coated alloy carbide particles was then injected into the melt by blowing through a lance with argon or in any other desired manner.
  • any other inert gas may be used, or the closed space above the melt in the induction furnace may be connected to a vacuum and particles may be added in any desired manner, for example by gravity feed, particularly where the vacuum is provided.
  • the induction coil was then turned on so that the melt was mixed.
  • Other techniques to avoid oxidation may be used such as, use of a flux or addition of the coated alloy carbide powder as a cored wire, although the flux may inhibit dispersion of particles in the melt and a cored wire would be expensive.
  • the powder of coated alloy carbide particles comprises:- 27% coating metal 30% Ti 35% W Balance C (of which 0.5% was free carbon) and usual incidentals.
  • the coating metal comprised 59% Ni and 41% iron (including up to 0.5% free carbon and usual residuals).
  • the metal was poured into a ladle where it remained at a temperature corresponding to the liquidus temperature plus about 170 - 180°C and then the metal was cast into the mould of the spin casting plant wherein the temperature was the liquidus temperature plus about 80 - 110°C.
  • the precise temperature depends upon the size, the smaller moulds being hotter and the larger cooler.
  • FIG. 9 is an optical D.I.C. (differential interference contrast) micrograph at x 300 magnification, unetched, of a sample taken from the middle of the shell and shows a matrix with graphite flakes and small uniformly and randomly distributed alloy carbide particles.
  • the microstructure was similar to that of Example I with the alloy coated particles being distributed throughout the matrix and the transformation carbide.
  • U.T.S. (ultimate tensile stress) test was performed on another sample from the shell and this showed the sample had a U.T.S. (Ultimate tensile stress) of 600 - 700 MPa.
  • An indefinite chill cast iron of the same composition but without the alloy carbide particles has a U.T.S. (ultimate tensile stress) of 385-493 MPa.
  • a composite roll comprising a shell of High Chromium iron and a nodular cast iron core was made by the spin casting technique of Example II using an argon atmosphere.
  • the shell metal had the following composition:- T.C. 2.95 Si 1.63 S 0.035 P 0.040 Mn 0.95 Ni 0.77 Cr 17.28 Mo 2.08 Ca 0.93 Pb 0.0081 V 0.031 Fe and usual residuals Balance
  • the powder coated alloy carbide was as described in Example I.
  • the powder was added to the metal in amounts equivalent to 10% by weight. 5% by weight was present in the solid metal.
  • the metal has a liquidus temperature of 1255°C and was heated to an operating temperature of 1560°C.
  • the temperatures in the ladle and in the spin casting plant were related to the liquidus temperature similarly as in Example II the temperature on adding to the spin casting plant being 1345°C. After solidification of the roll samples were taken as in Example II.
  • Figure 10 is a scanning election microscope micrograph at x 350 magnification of a sample taken from the middle of the shell.
  • Figure 11 is a similar micrograph but at x 3000 magnification. It will be seen that the discrete added alloy carbide particles are randomly and uniformly distributed and are present in both the matrix and in the transformation carbide. The carbide had largely separated into dark angular titanium rich particles about 1-10 micron in size and pinkish, rounded tungsten-rich particles generally less than about 5 micron in size. EDAX (energy dispersive X-ray) analysis revealed that the tungsten-rich particles also contains high levels of molybdenum whilst the metal itself contains low levels of titanium and tungsten in solution, both in the matrix and the transformation carbide. This points to the dissolution of the alloy carbide particles of (TiW)C in the melt, or at least their tungsten-rich outer layers, followed by their reprecipitation after solidification.
  • a U.T.S. (ultimate tensile stress) test was performed on a similar sample from the shell and this showed the sample had a U.T.S. (ultimate tensile stress) of 800-850 MPa.
  • a high chromium iron of the same composition but without the alloy carbide addition has a U.T.S. (ultimate tensile stress) of 740-830 MPa.
  • carbide particles of the same kind as described hereinbefore in connection with the first example were added to the melt in the melting furnace in an amount equivalent to 10% by weight.
  • the metal was then allowed to remain in the furnace as before to recover its tapping temperature and an ingot was then cast.
  • This ingot was then step forged in an open die forge to form a round bar in three reductions as follows:
  • the resultant forging was heat treated to simulate a conventional forged roll heat treatment.
  • Micrographs were taken at a magnification of x400 at different positions and on transverse and longitudinal sections. These showed that the forging had a substantially uniform microstructure throughout Figure 8 is an example of one of these micrographs taken on a longitudinal section.
  • FIG. 13 An electroslag remelting apparatus is shown in Figure 13 and is of essentially conventional kind comprising a cylindrical water cooled mould 10 which is movable vertically upwardly or downwardly.
  • An electrode holder 11 holds, for example by being welded thereto, the upper end of a consumable electrode 12. Initially, the bottom end of the consumable electrode is immersed in molten slag 30 contained between a bottom plate 13 and the wall of the mould 10. Electric current is then passed to cause the lower end of the electrode to melt and as the droplets of metal fall from the lower end of the electrode 12 they pass through the slag and are refined and then solidify to form an ingot 14.
  • the consumable electrode 12 comprises an inner body 120 having welded to its external surface 121 a hollow cladding 122 which comprises a plurality of discrete tubular elements 123 in the form of tubes 124 containing powder 125.
  • the inner body 120 is made of low alloy steel, cast iron or mild steel such as 0.2% carbon steel.
  • the tubes 124 are made of mild steel in the present example but may be made of stainless steel and if desired the tubes may be made of high alloy steel or cast iron or indeed in any material of suitable composition such as Carbon 0.5% - 3% Aluminium 0.0% - 1% Molybdenum 0.5% - 5% Vanadium 0.0% - 12% Chromium 0.5% - 15% Tungsten 0.0% - 8% Silicon 0.0% - 3% Titanium 0.0% - 8% Nickel 0.0% - 5% Iron and usual residuals - balance.
  • the tubes have a composition lying in the range:- Carbon 0.5% - 3% Aluminium 0.0% - 0.1% Molybdenum 0.5% - 5.0% Vanadium 0.1% - 12% Chromium 0.5% - 15% Tungsten 0.1% - 8% Silicon 0.0% - 3% Titanium 0.1% - 8% Nickel 0.1% - 5% Iron and usual residuals - balance.
  • the tube may have the following composition: Carbon 1 % Molybdenum 2.5% Vanadium 0.7% Chromium 14% Iron and usual residuals - Balance
  • the inner body may comprise a low alloy steel which may comprise: Carbon 0.4% Chromium 1% Nitrogen up to 0.1% Iron and usual residuals - Balance
  • the tubes may comprise other relatively high alloy metal such as:- Carbon 3% Molybdenum 5% Vanadium 8% Nickel 2% Iron and usual residuals - balance Carbon 1% Vanadium 12% Iron and usual residuals - balance Carbon 2% Tungsten 5% Titanium 5% Iron and usual residuals - balance Carbon 3% Silicon 2% Iron and usual residuals - balance
  • the inner body may comprise other relatively low alloy metal such as:- Carbon 0.2% Chromium 0.5% or Carbon 3% Silicon 2% or plain cast iron or mild steel.
  • the tubes may be provided solely to hold the powder 125 so could be composed of material of the same composition as the inner body or indeed may be made of suitable non-metallic material, such as silica, of a melting point so as to melt in the bath at a desired rate to release the alloying addition.
  • suitable non-metallic material such as silica
  • the above described materials are applicable to hollow cladding of any suitable configuration.
  • the tubes have the following composition: Carbon 0.2% Iron and usual residuals - balance
  • the powder comprises a mixture of coated alloy carbide particles as described hereinbefore in connection with Example I (but may be any of the other coated alloy carbide particles described hereinbefore) and of particles of an alloying ingredient or ingredients.
  • the powder may comprise:- Carbon up to 10% (with 5% as graphite) Tungsten 35-40% Titanium 30-40% Iron, carbide and usual residuals - balance
  • Some of the carbon is combined with the Tungsten and the Titanium as intermetallic compound but the Tungsten and Titanium are combined as a solid solution and a proportion of the Carbon present is as free graphite.
  • the powder mixture has the following composition: Chromium 2% Tungsten 40% Titanium 40% Molybdenum 1% Vanadium 1% Carbon 6% Iron, carbide and usual residuals Balance
  • the powder mixture has the following composition:- Chromium 2% Tungsten 35% Titanium 30% Molybdenum 1% Vanadium 1% Carbon 6% Iron, carbide and usual residuals Balance
  • one or more of the alloying elements may be present in the powder mixture, either as elements or combined with the carbon as inter-metallic compound or alloy.
  • the powder may be made of a powdered alloy of any one of the compositions or range of compositions described as being suitable for the tubes mentioned above or may be made of alloy of other compositions or of components which provide such compositions.
  • the amount of carbide particles added is such as to achieve up to 1-20% by volume of carbide particles in the surface part.
  • the tubes 124 in the present example are 16mm OD (outside diameter), 13mm ID (inside diameter) but may lie in the range from 6mm ID (inside diameter) to 28mm ID with appropriate (outside diameter) OD.
  • the tubes are provided with restrictions at intervals along their length so as to hold discrete amounts of carbide powder at positions along the length of the tubes, for example, such restrictions may be provided every 10cm.
  • restrictions are provided by crimping the tubes so as to close or substantially to close their bore but, of course, such restrictions may be provided in any other desired way.
  • the tubes 124 are attached to the inner body 120 so as to extend longitudinally thereof parallel to the longitudinal axis of the inner body but, if desired, a single tube or tubes may be wound helically around the inner body or one or more tubes may extend circumferentially around the body so as to lie in a plane which is perpendicular to the longitudinal axis of the inner body so long as the tubes are of the correct size to hold the correct amount of powder to be released into the melt at the longitudinal position of the body.
  • one or more tubes may be arranged to extend around the inner body in a plane or respective plane which is inclined to the longitudinal axis of the inner body at less than a right angle.
  • the cladding may comprise a hollow sleeve, for example, a sleeve comprising inner and outer generally cylindrical walls inter-connected by generally annular shaped walls with the space between the walls containing powder as described hereinbefore and the sleeve being mounted, for example, by welding or by virtue of being a push fit on the inner body.
  • the hollow sleeve is provided with restrictions in its wall at suitable positions along the length of the sleeve so as to divide the powder into discrete amounts for release into the melt pool sequentially as the sleeve and inner body are melted.
  • the melting point of an alloy added with the carbides for example Tungsten, Titanium solid solution, which can at least partly melt in the melt bath and of the alloy carbides are greater than the melting point of the slag 30 and of the inner body 120 of the consumable electrode 12.
  • the melting point of the cladding tube/sleeve metal of the tubes and/or of any alloy ingredient may be 40"C below the melting point of the inner part 20 and 60°C above the melting point of the slag 30.
  • the melting point of the tubes 22 is, in the present example, 1530°C.
  • the inner part may have a melting point lying in the range 1160"C to 1600°C and the cladding may have a melting point lying in the range 1160°C to 1600°C.
  • the melting point of the inner and outer parts may differ by 20°C to 60°C.
  • the slag may have a melting point which differs from the lower of the melting point of the inner part and the cladding by 20°C to 60°C.
  • the mould is water cooled to a temperature lying in the range of 15°C to 65°C and the molten metal pool 31 has a temperature lying in the range 1400°C to 1600°C may be in the range 1160°C to 1600°C.
  • the voltage and current used in the electroslag remelting operation are manipulated so that there is a relatively high voltage and a relatively low current, or vice versa and in addition the composition of the slag is adjusted so as to provide a relatively viscous slag. As a result turbulence in the slag and the melt pool are minimised so that a desired composition gradient is achieved.
  • the voltage and current used are manipulated so that the floor of the melt pool is relatively flat.
  • the metal droplets leaving the cladding of the electrode are more dense than the metal droplets leaving the inner body of the electrode when they are more highly alloyed. This results in the droplets from the cladding of the electrode falling downwardly adjacent to the wall of the mould and, because the floor of the melt pool is relatively flat, there is relatively little tendency for these droplets to run towards the middle of the melt pool before they have solidified as a result of their spatial and temperature proximity to the mould wall.
  • the composition of the slag is adjusted to reduce the ionic capacity of the slag by adjusting the balance of the silicon, calcium and aluminium in the slag to reduce the tendency for electromagnetic stirring as well as the composition of the slag being adjusted to provide a relatively higher viscosity.
  • the slag has the following composition:- 33 1 / 3 % CaO, 33 1 / 3 % CaF 2 , 33 1 / 3 % Al 2 0 3 .
  • the slag may have a composition of 20% CaO, 80% CaF 2 , 0% Al 2 0 3 .
  • the cooling rate provided by the water cooling to the mould may be adjusted by adjusting the raw temperature of the mould to lie in the range 15°C to 65°C. In addition, the rate of movement of the mould may also be adjusted.
  • the electrode has a diameter which is about 0.9% of the diameter of the mould cavity.
  • the electrode is arranged so that approximately 20%, by weight, of the electrode comprises cladding and the balance is provided by the inner body. This ratio may lie in the range 1% to 40%.
  • the melting point of the cladding has been described as being lower than the melting point of the metal of the inner body, if desired this may be reversed.
  • droplets of liquid metal are solid particles of the metal carbide which does not melt, from the tubes 124 and powder 125 fall generally vertically downwardly and because of the relatively close spatial and temperature proximity to the wall of the mould 110 the droplets solidify relatively rapidly, at or adjacent to the mould wall and the carbide particles are trapped by the solidifying melt adjacent the mould wall, so that the metal at the surface of the ingot 14 has a relatively high uniform distribution of alloy and alloy carbides as well as having a composition of matrix substantially similar to the composition of the metal of the tubes 124.
  • the metal droplets falling from the middle of the bottom of the inner part fall vertically downwardly and thus the metal solidifying at the centre of the ingot has a composition substantially similar to the composition of the inner part of the electrode.
  • metal from the cladding is of greater density than the metal from the inner body as this causes the droplets to fall downwardly adjacent to the mould wall together and by the hereinbefore mentioned precautions to avoid mixing, low slag viscosity, low slag electromagnetic stirring and a relatively flat melt pool base.
  • the ingot has a relatively uniform transition region between the inner part and the surface part.
  • the ingot, and hence any resulting product such as a roll as described hereinbefore, has an elastic modulus which increases in direct proportion to the amount of the distribution of the alloy/alloy carbide through the ingot cross-section.
  • composition at the surface of the ingot is: Carbon 0.5% Molybdenum 0.2% Vanadium 0.9% Tungsten 1.2% Chromium 0.5% Titanium 0.15% Iron, carbide and usual residuals balance
  • composition at the centre of the ingot is: Carbon 0.5% Molybdenum 0.1% Tungsten 0.3% Titanium 0.03% Vanadium 0.2% Chromium 0.5% Iron, carbide and usual residuals balance
  • the variation in composition is believed to arise due to the relatively higher diffusion of chromium and carbon compared with the relatively lower diffusion and more dense tungsten and titanium.
  • composition gradient does not exceed 40% per 100mm in the radial direction and this condition applies with any position along the longitudinal extent of the roll.
  • the electroslag remelting apparatus and method of operation described in connection with Example V may also used but with the operating conditions modified so as to aim to provide a uniform composition roll, for example the voltage and current used manipulated so that the floor of the melt pool is relatively deep.
  • the operating conditions modified so as to aim to provide a uniform composition roll for example the voltage and current used manipulated so that the floor of the melt pool is relatively deep.
  • conventional operating conditions and slag compossations were used.
  • An electrode comprising an inner part, with an outer cladding of tubular configuration both made of low carbon steel was made with the space therebetween containing alloy carbide powder as described in connection with Example V. Quantities were calculated for a target addition of 1 wt%.
  • EDAX energy dispersive X-ray
  • the low carbon steel of this example contained about 0.1% nitrogen it is considered that at least some of this nitrogen has formed titanium carbo-nitride particles and hence that at least some of the above mentioned carbide particles comprise such titanium carbo-nitride particles which may also contain tungsten.
  • compositions are expressed herein in % by weight.
  • references to particle size are to the largest dimension of the largest particle unless otherwise described.

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Claims (51)

  1. Procédé de fabrication d'un cylindre de laminoir comprenant les étapes consistant à ajouter à de la fonte ou à de l'acier coulé liquide, des particules de carbure d'alliage solide et permettre par la suite à la fonte ou à l'acier coulé de solidifier, dans lequel les particules de carbure de l'alliage présentent une densité de 6 à 8 mg par cm3 qui correspond à celle de la fonte ou de l'acier coulé et les particules de carbure solide sont enrobées avec un métal qui permet que le mouillage se produise entre les particules et la fonte ou l'acier coulé liquide et à couler ledit métal pour procurer au moins une partie externe du cylindre.
  2. Procédé selon la revendication 1, dans lequel le métal d'enrobage comprend un alliage de carbone de fer ou du fer, ou un alliage de deux ou plus éléments choisis dans le groupe comprenant le fer, le nickel, le cuivre, le titane et le carbone, ou le nickel ou le cuivre et les résidus habituels et/ou de l'azote.
  3. Procédé selon la revendication 1 ou 2, dans lequel le métal d'enrobage présente une température de fusion qui est à l'intérieur d'approximativement 20°C à 30°C de la température du métal ferreux pour pièces de machine auquel lesdites particules de carbure enrobées sont ajoutées.
  4. Procédé selon l'une quelconque des revendications précédentes, dans lequel les particules de carbone de l'alliage sont enrobées de fer ou d'un alliage de fer ayant une teneur en carbone plus faible que celle de la fonte ou de l'acier coulé auquel elles sont ajoutés et les particules de carbure de l'alliage enrobées sont ajoutées à la fonte ou à l'acier coulé et autorisées à séjourner dans celui-ci pendant un temps suffisamment long pour que le carbone provenant de la fonte ou de l'acier coulé puisse diffuser dans l'enrobage et produire ainsi une composition qui présente une température de fusion qui correspond à la température opératoire de la fonte ou de l'acier coulé.
  5. Procédé selon l'une quelconque des revendications précédentes, dans lequel les particules de carbure de l'alliage enrobées sont ajoutées à la fonte ou à l'acier coulé liquide soit dans le four de fusion, soit dans une poche de coulé dans laquelle le métal a été versé à partir du four de fusion ou dans le flux d'un métal ayant été versé depuis le four de fusion dans la poche ou dans le flux de métal ayant été versé depuis la poche dans un moule.
  6. Procédé selon la revendication 5, dans lequel les particules de carbone de l'alliage enrobées sont ajoutées dans le four de fusion.
  7. Procédé selon l'une quelconque des revendications précédentes, dans lequel les particules de carbure de l'alliage enrobées sont ajoutées à la fonte ou à l'acier coulé dans un environnement inerte.
  8. Procédé selon l'une quelconque des revendications précédentes, dans lequel les particules de carbure de l'alliage enrobées sont ajoutées à la fonte ou à l'acier coulé fondu sous la forme d'une poudre comprenant des particules de poudre ayant une dimension particulaire allant jusqu'à 2 mm et, de préférence, d'environ 500 µm (500 microns) et contenant des particules de carbure de l'alliage ayant une dimension particulaire allant jusqu'à 10 µm (10 microns) et, de préférence, dans la plage de 1 à 5 µm (1 à 5 microns) et, encore plus préférentiellement, de 2 à 5 µm (2 à 5 microns).
  9. Procédé selon l'une quelconque des revendications précédentes, dans lequel les particules de carbure de l'alliage enrobées sont ajoutées à la fonte ou à l'acier coulé fondu sous la forme d'une poudre, dans laquelle les particules de poudre comprennent : 25% méral d'enrobage 30% Ti 35% W Rest Carbone (incluant jusqu'à 3,5 % de carbone non combiné) et les résidus habituels.
  10. Procédé selon l'une quelconque des revendications précédentes, dans lequel le métal d'enrobage comprend du fer alfa totalement ou sensiblement totalement jusqu'à 3,5 % de carbone non combiné.
  11. Procédé selon l'une quelconque des revendications 1 à 8, dans lequel les particules de carbure de l'alliage enrobées sont ajoutées à la fonte ou à l'acier coulé fondu sous la forme d'une poudre, dans laquelle les particules de poudre comprennent : 27% métal d'enrobage 30% Ti 35% W Rest carbone incluant jusqu'à 0,5 % de carbone non combiné) et les résidus habituels.
  12. Procédé selon l'une quelconque des revendications 1 à 8 ou la revendication il dans lequel le métal d'enrobage comprend un alliage de fer, de nickel et de carbone.
  13. Procédé selon la revendication 12, dans lequel l'alliage de fer, de nickel et de carbone comprend : 59% nickel 41% fer et jusqu'à 0,5 % de carbone non combiné et de résidus habituels.
  14. Procédé selon l'une quelconque des revendications 1 à 4 ou selon l'une quelconque des revendications 8 à 13 en combinaison avec l'une quelconque des revendications 1 à 4, dans lequel les particules de carbure de l'alliage enrobées sont ajoutées pendant une opération de raffinement sous laitier électroconducteur.
  15. Procédé selon l'une quelconque des revendications précédentes, dans lequel le carbure de l'alliage est choisi dans le groupe comprenant le chrome, le molybdène, le titane, le tungstène, le niobium, le vanadium ou leurs carbures mélangés tels que Cr7C3, (CrMo)7C3 ou leurs carbonitrures mélangés.
  16. Procédé selon l'une quelconque des revendications précédentes, dans lequel le carbure est un carbure de titane et de tungstène mélangés du type (TiW)C où le rapport du titane au tungstène est d'environ 1 : 1 en poids et, de préférence, dans la plage des rapports :
       1 : 1 à 1 : 1,17.
  17. Procédé selon l'une quelconque des revendications précédentes, dans lequel les particules de carbure de l'alliage présentent une dimension maximale allant jusqu'à 10 µm (10 microns) et, de préférence, de 1 à 5 µm (1 à 5 microns) et, encore plus préférentiellement, de 2 à 5 µm (2 à 5 microns).
  18. Procédé selon l'une quelconque des revendications précédentes, dans lequel la quantité de particules de carbure de l'alliage ajoutées est telle à pouvoir obtenir jusqu'à 20 %, de préférence jusqu'à 5 à 20 % en volume de particules de carbure de l'alliage dans le métal solide.
  19. Procédé selon la revendication 18, dans lequel la teneur en carbure de l'alliage est dans la plage de 0,1 à 20 % en volume et, encore plus préférentiellement, de 3 à 10 % lorsqu'un effet de durcissement sur la base de la loi des mélanges est procuré.
  20. Procédé selon la revendication 18, dans lequel la teneur en carbure de l'alliage est dans la plage allant de 1 % à environ 0,5 % en volume ou allant de 1 % à environ 0,1 % en volume ou moins lorsqu'un effet de durcissement basé sur une modification de la transformation de la micro structure est procuré.
  21. Procédé selon l'une quelconque des revendications précédentes, dans lequel la fonte ou l'acier coulé est choisi dans le groupe qui est constitué du fer, de la fonte au chrome, de l'acier fortement allié, de l'acier à outils, de l'acier moyennement allié, de l'acier faiblement allié, du fer S.G., de la fonte ou de l'acier coulé ayant une teneur en carbone se trouvant dans la plage de 0,3 à 3,8 % et qui peut contenir de 1'azote jusqu'à 0,1 %.
  22. Cylindre de laminoir ayant au moins une partie externe qui comprend un produit de fonte ou d'acier coulé comprenant un alliage de carbone ayant une micro structure qui résulte de la transformation de phase lors du refroidissement et ayant dispersé dans celle-ci des particules de carbure d'alliage discrètes dans lequel le carbure d'alliage a une composition telle que la densité du carbure de l'alliage se trouve dans la plage de 6 à 8mg par cm3 qui correspond à celle de la fonte ou de l'acier coulé.
  23. Cylindre de laminoir selon la revendication 22, dans lequel la micro structure comprend une matrice et un carbure de transformation qui résulte de la transformation de phase du métal ferreux pour pièces de machine.
  24. Cylindre de laminoir selon la revendication 23, dans lequel les particules de carbure de l'alliage discrètes sont distribuées dans la matrice.
  25. Cylindre de laminoir selon la revendication 23 ou la revendication 24, dans lequel les particules de carbure de l'alliage discrètes sont distribuées dans le carbure de transformation.
  26. Cylindre de laminoir selon l'une quelconque des revendications 22 à 25, dans lequel les particules de carbure de l'alliage discrètes sont distribuées uniformément dans la micro structure.
  27. Cylindre de laminoir selon l'une quelconque des revendications précédentes, dans lequel le carbure de l'alliage est choisi dans le groupe comprenant le chrome, le molybdène, le titane, le tungstène, le niobium, le vanadium ou leurs carbures mélangés tels que Cr7C3, (CrMo)7C3 ou leurs carbonitrures mélangés.
  28. Cylindre de laminoir selon l'une quelconque des revendications précédentes, dans lequel le carbure est un carbure de tungstène et de titane mélangés du type (TiW)C où le rapport du titane au tungstène est d'environ 1 : 1 en poids et, de préférence, dans la plage des rapports :
       1 : 1 à 1 : 1,17
  29. Cylindre de laminoir selon l'une quelconque des revendications précédentes, dans lequel les particules de carbure de l'alliage présentent une dimension maximale allant jusqu'à 10 µm (10 microns), de préférence de 1 à 5 µm (1 à 5 microns) et, encore plus préférentiellement, de 2 à 5 µm (2 à 5 microns).
  30. Cylindre de laminoir selon l'une quelconque des revendications précédentes, dans lequel la quantité de particules de carbure de l'alliage ajoutées est telle à pouvoir obtenir jusqu'à 20 %, de préférence jusqu'à 5 à 20 % en volume de particules de carbure de l'alliage dans le métal solide.
  31. Produit selon la revendication 30, dans lequel la teneur en carbure de l'alliage est dans la plage de 0,1 à 20 % en volume et, encore plus préférentiellement, de 3 à 10 % lorsqu'un effet de durcissement basé sur la loi des mélanges est procuré.
  32. Cylindre de laminoir selon la revendication 30, dans lequel la teneur en carbure de l'alliage est dans la plage allant de 1 % à environ 0,25 % en volume ou allant de 1 % à environ 0,1 % en volume ou moins lorsqu'un effet de durcissement basé sur une modification de la transformation de la micro structure est procuré.
  33. Cylindre de laminoir selon l'une quelconque des revendications précédentes, dans lequel la fonte ou l'acier coulé est choisi dans le groupe qui est constitué du fer, de la fonte au chrome, de l'acier fortement allié, de l'acier à outils, de l'acier moyennement allié, de l'acier faiblement allié, du fer S.G., de la fonte ou de l'acier coulé ayant une teneur en carbone se trouvant dans la plage de 0,3 à 3,8 % et qui peut contenir de l'azote jusqu'à 0,1 %.
  34. Procédé selon l'une quelconque des revendications 1 à 21, dans lequel le cylindre de laminoir est un cylindre de laminoir composite du type ayant un noyau et une coquille externe avec, facultativement, au moins une couche intermédiaire, dans laquelle la coquille constitue ladite partie externe.
  35. Cylindre de laminoir selon l'une quelconque des revendications 22 à 33, dans lequel le cylindre de laminoir est un cylindre de laminoir composite du type ayant un noyau et une coquille externe avec, facultativement, au moins une couche intermédiaire, dans laquelle la coquille constitue ladite partie externe.
  36. Procédé selon la revendication 34, dans lequel les particules de carbone de l'alliage sont introduites dans un métal ferreux pour pièces de machine fondue dont la coquille doit être formée et ensuite le métal ferreux pour pièces de machine ayant les particules de carbure de l'alliage dans celui-ci est versé dans un moule.
  37. Procédé selon la revendication 34 ou la revendication 36, dans lequel le cylindre composite est fabriqué par coulée centrifuge.
  38. Procédé selon l'une quelconque des revendications 1 à 21, dans lequel le cylindre est fabriqué en effectuant une opération de raffinement sous laitier électroconducteur sur une électrode consommable qui comprend un corps interne muni d'un placage externe comprenant un élément creux contenant lesdites particules de carbure de l'alliage enrobées.
  39. Procédé selon la revendication 38, dans lequel l'élément creux contient également un ingrédient de l'alliage sous forme de poudre.
  40. Procédé selon la revendication 38 ou la revendication 39, dans lequel l'opération de raffinement sous laitier électroconducteur est effectuée pour procurer un cylindre comprenant une partie interne ayant une première composition et une partie de surface ayant une seconde composition qui est différente de la première composition et le métal du cylindre entre la partie interne et la partie de surface ayant une composition qui change de la première composition à la seconde composition sans discontinuité.
  41. Procédé selon la revendication 38 ou la revendication 40, dans lequel l'opération de raffinement sous laitier électroconducteur est effectuée pour procurer un cylindre ayant une composition sensiblement uniforme sur toute la section transversale du cylindre.
  42. Procédé selon la revendication 34 ou la revendication 36, dans lequel le cylindre est fabriqué par placage par raffinement sous laitier électroconducteur ou par placage par pulvérisation.
  43. Procédé selon l'une quelconque des revendications 1 à 21, dans lequel le cylindre est fabriqué par coulage statique monobloc en remplissant un moule fixe avec seulement de la fonte ou de l'acier coulé.
  44. Procédé selon l'une quelconque des revendications 1 à 21, dans lequel un cylindre est fabriqué par un procédé de coulée statique versée deux fois.
  45. Procédé selon l'une quelconque des revendications 34, 36, 37 à 39 ou des revendications 42 à 44, dans lequel le noyau est constitué de fonte en flocons, compact, vermiculaire ou nodulaire ou d'acier coulé en flocons, compact, vermiculaire ou nodulaire.
  46. Procédé selon l'une quelconque des revendications 1 à 21 comprenant l'étape consistant à couler un lingot dudit métal et à forger ensuite le lingot pour procurer un cylindre forgé suivi par le traitement thermique du cylindre forgé.
  47. Cylindre de laminoir selon l'une quelconque des revendications 22 à 33 ou 35 dans lequel le cylindre de laminoir est un cylindre forgé
EP94900231A 1992-11-19 1993-11-19 Metaux ferreux coules, en particulier pour cylindres de laminage Expired - Lifetime EP0680521B1 (fr)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
GB929224271A GB9224271D0 (en) 1992-11-19 1992-11-19 Engineering ferrous metals
GB9224271 1992-11-19
GB9315356 1993-07-23
GB939315356A GB9315356D0 (en) 1993-07-23 1993-07-23 Engineering ferrous metals
PCT/GB1993/002380 WO1994011541A1 (fr) 1992-11-19 1993-11-19 Metaux ferreux industriels, en particulier fonte et acier

Publications (2)

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EP0680521A1 EP0680521A1 (fr) 1995-11-08
EP0680521B1 true EP0680521B1 (fr) 2001-03-14

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EP94900231A Expired - Lifetime EP0680521B1 (fr) 1992-11-19 1993-11-19 Metaux ferreux coules, en particulier pour cylindres de laminage

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EP (1) EP0680521B1 (fr)
JP (1) JPH08506143A (fr)
KR (1) KR950704526A (fr)
AT (1) ATE199747T1 (fr)
AU (1) AU5530494A (fr)
BR (1) BR9307499A (fr)
DE (1) DE69330035T2 (fr)
DK (1) DK0680521T5 (fr)
ES (1) ES2155087T3 (fr)
GB (1) GB2289288B (fr)
WO (1) WO1994011541A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10253577A1 (de) * 2002-11-15 2004-05-27 Ab Skf Verfahren zur Herstellung eines dispersionsgehärteten Eisenwerkstoffs

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU704855B2 (en) * 1995-06-06 1999-05-06 Akers Ab Cast iron indefinite chill roll produced by the addition of niobium
CA2199396C (fr) * 1995-06-07 2001-04-24 Lockheed Martin Energy Systems, Inc. Enveloppe pour projectiles et explosifs sans plomb protegeant l'environnement
AT405944B (de) * 1996-04-19 1999-12-27 Holderbank Financ Glarus Verfahren zum reduzieren von oxidischen schlacken
EP1022353A1 (fr) * 1999-01-21 2000-07-26 Basf Aktiengesellschaft Procédé de production de matériaux durs revêtus de métal
AT408666B (de) 1999-04-22 2002-02-25 Weinberger Eisenwerk Gusswerkstoff und verfahren zu dessen herstellung
SE522667C2 (sv) * 2000-05-16 2004-02-24 Proengco Tooling Ab Förfarande för framställning av en legering baserad på järn innehållande kromkarbid med inlöst volfram och en sådan legering
EP1452611B1 (fr) * 2001-11-13 2005-03-23 Fundacion Inasmet Fabrication de produits en matieres metalliques structurales renforcees par des carbures
BE1018130A3 (fr) * 2008-09-19 2010-05-04 Magotteaux Int Materiau composite hierarchique.
BE1018129A3 (fr) * 2008-09-19 2010-05-04 Magotteaux Int Impacteur composite pour concasseurs a percussion.
DE102009005537A1 (de) * 2009-01-20 2010-07-29 Nano-X Gmbh Verfahren zum Modifizieren von Metallschmelzen
CN102822368B (zh) * 2010-02-01 2015-08-26 伟尔矿物澳大利亚私人有限公司 用于高抗冲应用的金属合金
WO2011094800A1 (fr) * 2010-02-05 2011-08-11 Weir Minerals Australia Ltd Matériaux à base de métal dur
KR101360536B1 (ko) * 2011-12-27 2014-02-10 주식회사 포스코 마르텐사이트계 스테인리스 강판의 제조방법
CN105397068B (zh) * 2015-11-06 2018-02-16 姜向群 电渣熔铸三金属复合耐磨锤头的制作方法
CN111172448B (zh) * 2018-11-12 2021-09-24 中国科学院金属研究所 一种厚大断面高均质塑料模具钢制备方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0550725A1 (fr) * 1991-07-26 1993-07-14 London Scandinavian Metall Alliages de matrices metalliques.

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO117628B (fr) * 1964-09-11 1969-09-01 Corning Glass Works
DE3315125C1 (de) * 1983-04-27 1984-11-22 Fried. Krupp Gmbh, 4300 Essen Verschleissbestaendiger Verbundkoerper und Verfahren zu seiner Herstellung
EP0386515A3 (fr) * 1989-03-04 1990-10-31 Fried. Krupp Gesellschaft mit beschränkter Haftung Procédé pour la production d'un composite métallique qui a une région présentant une résistance élevée à l'usure et dispositif pour la mise en oeuvre du procédé
US5023145A (en) * 1989-08-21 1991-06-11 Bimex Corporation Multi carbide alloy for bimetallic cylinders
US5030519A (en) * 1990-04-24 1991-07-09 Amorphous Metals Technologies, Inc. Tungsten carbide-containing hard alloy that may be processed by melting

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0550725A1 (fr) * 1991-07-26 1993-07-14 London Scandinavian Metall Alliages de matrices metalliques.

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10253577A1 (de) * 2002-11-15 2004-05-27 Ab Skf Verfahren zur Herstellung eines dispersionsgehärteten Eisenwerkstoffs
DE10253577B4 (de) * 2002-11-15 2011-05-19 Ab Skf Verfahren zur Herstellung eines dispersionsgehärteten Eisenwerkstoffs

Also Published As

Publication number Publication date
DE69330035D1 (de) 2001-04-19
EP0680521A1 (fr) 1995-11-08
GB9510006D0 (en) 1995-07-12
AU5530494A (en) 1994-06-08
GB2289288B (en) 1997-04-16
DE69330035T2 (de) 2001-06-21
ATE199747T1 (de) 2001-03-15
JPH08506143A (ja) 1996-07-02
DK0680521T5 (da) 2001-06-11
KR950704526A (ko) 1995-11-20
ES2155087T3 (es) 2001-05-01
BR9307499A (pt) 1999-06-01
GB2289288A (en) 1995-11-15
WO1994011541A1 (fr) 1994-05-26
DK0680521T3 (da) 2001-04-17

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