[go: up one dir, main page]

US20040050114A1 - Method for making mineral wool, cobalt-based alloys therefor and other uses - Google Patents

Method for making mineral wool, cobalt-based alloys therefor and other uses Download PDF

Info

Publication number
US20040050114A1
US20040050114A1 US10/276,316 US27631603A US2004050114A1 US 20040050114 A1 US20040050114 A1 US 20040050114A1 US 27631603 A US27631603 A US 27631603A US 2004050114 A1 US2004050114 A1 US 2004050114A1
Authority
US
United States
Prior art keywords
alloy
less
cobalt
temperature
weight
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.)
Abandoned
Application number
US10/276,316
Other languages
English (en)
Inventor
Patrice Berthod
Jean-Luc Bernard
Christophe Liebaut
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.)
Saint Gobain Isover SA France
Saint Gobain SEVA SA
Original Assignee
Saint Gobain Isover SA France
Saint Gobain SEVA SA
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 Saint Gobain Isover SA France, Saint Gobain SEVA SA filed Critical Saint Gobain Isover SA France
Assigned to SAINT-GOBAIN SEVA, SAINT-GOBAIN ISOVER reassignment SAINT-GOBAIN SEVA ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BERNARD, JEAN-LUC, LIEBAUT, CHRISTOPHE, BERTHOD, PATRICE
Publication of US20040050114A1 publication Critical patent/US20040050114A1/en
Priority to US11/843,949 priority Critical patent/US8398791B2/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01—Manufacture of glass fibres or filaments
    • C03B37/04—Manufacture of glass fibres or filaments by using centrifugal force, e.g. spinning through radial orifices; Construction of the spinner cups therefor
    • C03B37/047—Selection of materials for the spinner cups
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/08—Bushings, e.g. construction, bushing reinforcement means; Spinnerettes; Nozzles; Nozzle plates
    • C03B37/095—Use of materials therefor
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/07—Alloys based on nickel or cobalt based on cobalt
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/10—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of nickel or cobalt or alloys based thereon

Definitions

  • the present invention relates to a process for manufacturing mineral wool by fiberizing a molten mineral composition, using tools made of a cobalt-based alloy having a high-temperature mechanical strength in an oxidizing medium, such as molten glass, and to cobalt-based alloys that can be used at high temperature, especially for the production of articles for the manufacture and/or hot-conversion of glass or other mineral material, such as components of machines for manufacturing mineral wool.
  • One fiberizing technique consists in letting liquid glass drop continuously into an assembly of parts rotating at a very high rotation speed about their vertical axis.
  • a master part called a “spinner dish”
  • An annular burner located above the outside of the spinner dish, which produces a downward blast of gas hugging the outer wall of the band, deflects these filaments downwards and attenuates them. The latter then “solidify” in the form of glass wool.
  • the spinner dish is a fiberizing tool which is highly stressed thermally (heat shocks when stopping and starting and the creation, in steady use, of a temperature gradient along the part), mechanically (centrifugal force, and erosion due to the passage of the glass) and chemically (oxidation and corrosion by the molten glass, and by the hot gasses expelled by the burner around the spinner dish). Its main modes of deterioration are: deformation of the vertical walls by hot creep, horizontal or vertical cracking, or wear of the fiberizing orifices by erosion, which purely and simply require the components to be replaced. Their constituent material must therefore withstand the above for a production time long enough to remain compatible with the technical and economic constraints of the process. For this purpose, materials are sought which exhibit a certain ductility, creep strength and corrosion and/or oxidation resistance.
  • a conventional material for producing these tools is a superalloy based on nickel and chromium, reinforced by chromium and tungsten carbides, which can be used up to a maximum temperature of about 1000 to 1050° C.
  • These alloys always contain chromium for oxidation resistance, and generally carbon and tungsten in order to obtain a reinforcing effect caused by the precipitation of carbides. They also contain nickel in solid solution, the nickel stabilizing the face-centred cubic crystal lattice of cobalt at all temperatures.
  • WO-A-99/16919 discloses a cobalt-based alloy having improved high-temperature mechanical properties, essentially comprising the following elements (in percentages by weight of the alloy): Cr 26 to 34% Ni 6 to 12% W 4 to 8% Ta 2 to 4% C 0.2 to 0.5% Fe less than 3% Si less than 1% Mn less than 0.5% Zr less than 0.1%,
  • the balance consisting of cobalt and inevitable impurities, the molar ratio of tantalum with respect to carbon being of the order of 0.4 to 1.
  • the objective of the invention was to be able to fiberize glass or a similar material at even higher temperatures in order to work within a more varied range of compositions of mineral materials.
  • the subject of the invention is a process for manufacturing mineral wool by internal centrifuging, in which a stream of molten mineral material is poured into a fiberizing spinner dish, the peripheral band of which is pierced by a multitude of orifices through which filaments of molten mineral material escape, these filaments then being attenuated into wool due to the action of a gas, characterized in that the temperature of the mineral material in the spinner dish is at least 1100° C.
  • the fiberizing spinner dish is made of a cobalt-based alloy comprising the following elements (in percentages by weight of the alloy): Cr 23 to 34% Ni 6 to 12% Ta 3 to 10% C 0.2 to 1.2% W 0 to 8% Fe less than 3% Si less than 1% Mn less than 0.5% Zr less than 0.1%,
  • the balance consisting of cobalt and inevitable impurities, the molar ratio of tantalum to carbon being at least 0.3.
  • This process is especially characterized by the use of an alloy very rich in tantalum compared with the known alloys.
  • the intragranular and intergranular reinforcement essentially makes use of the tantalum, which is present especially at the grain boundaries in the form of the carbide TaC.
  • the process according to the invention is characterized by the use of alloys having a good compromise between mechanical strength and oxidation resistance above 1100° C., and advantageously above 1150° C.
  • This compromise is obtained using alloys whose intergranular regions are rich in tantalum carbide precipitates which have a high melting point and fulfil a mechanical reinforcement function by preventing intergranular creep at very high temperature.
  • the high tantalum content present in the alloy furthermore has an appreciable effect on the oxidation behaviour:
  • the tantalum present in solid solution or in the form of fine intergranular carbides may form oxides (Ta 2 O 5 ) which mix with the self-passivating surface layer of chromium oxide (Cr 2 O 3 ) to which they further provide cohesion and bonding with respect to the alloy;
  • the intergranular tantalum carbides close to the surface of the spinner dish oxidize there to form Ta 2 O 5 , the clusters of Ta 2 O 5 forming “plugs” which prevent penetration by the aggressive medium (liquid glass, hot gases) into the intergranular spaces.
  • the alloy thus obtained remains stable at high temperature by virtue of the limited solid solubility of TaC at 1200-1300° C.
  • the process according to the invention therefore makes it possible to fiberize glass or a similar molten mineral composition having a liquidus temperature T liq of about 1100° C. or higher, more particularly 1140° C. or higher.
  • these molten mineral compositions may be fiberized within a temperature range (for the molten composition entering the spinner dish) of between T liq and T log2.5 where T log2.5 is the temperature at which the molten composition has a viscosity of 10 2.5 poise (dPa.s).
  • T log2.5 is the temperature at which the molten composition has a viscosity of 10 2.5 poise (dPa.s).
  • the corresponding compositions are, according to the invention, preferably those whose T liq is at least 1140° C.
  • compositions containing a significant amount of iron are compositions containing a significant amount of iron, these being less corrosive with respect to the constituent metal of the fiberizing components.
  • the process according to the invention advantageously uses an oxidizing mineral composition, especially one which is oxidizing with respect to chromium, capable of repairing or reconstituting the protective Cr 2 O 3 oxide layer which forms on the surface.
  • an oxidizing mineral composition especially one which is oxidizing with respect to chromium, capable of repairing or reconstituting the protective Cr 2 O 3 oxide layer which forms on the surface.
  • compositions containing iron essentially in the ferric form (oxide Fe 2 O 3 ), especially with a molar ratio of II and III oxidation states, expressed by the ratio FeO/(FeO+Fe 2 O 3 ) of about 0.1 to 0.3, especially 0.15 to 0.20, are preferable.
  • the mineral composition contains a high iron content allowing a rapid rate of reconstitution of the chromium oxide, with an iron oxide content (called “total iron” content, corresponding to the total iron content expressed conventionally in the form of equivalent Fe 2 O 3 ) of at least 3%, preferably at least 4%, and especially about 4 to 12%, particularly at least 5%.
  • total iron an iron oxide content
  • this corresponds to a content of ferric iron alone (Fe 2 O 3 ) of at least 2.7%, preferably at least 3.6%.
  • compositions are known, especially from WO-99/56525, and advantageously comprise the following constituents: SiO 2 38-52%, preferably 40-48% Al 2 O 3 17-23% SiO 2 + Al 2 O 3 56-75%, preferably 62-72% RO (CaO + MgO) 9-26%, preferably 12-25% MgO 4-20%, preferably 7-16% MgO/CaO ⁇ 0.8, preferably ⁇ 1.0 or ⁇ 1.15 R 2 O (Na 2 O + K 2 O) ⁇ 2% P 2 O 5 0-5% Total iron (Fe 2 O 3 ) ⁇ 1.7%, preferably ⁇ 2% B 2 O 3 0-5% MnO 0-4% TiO 2 0-3%.
  • compositions prove to be particularly suitable for the process according to the invention.
  • MgO being between 0 and 5%, especially between 0 and 2%, when R 2 O ⁇ 13.0%.
  • the mineral wool composition comprises the constituents mentioned below in the following percentages by weight: SiO 2 39-55%, preferably 40-52% Al 2 O 3 16-25%, — 17-22% CaO 3-35%, — 10-25% MgO 0-15%, — 0-10% Na 2 O 0-15%, — 6-12% K 2 O 0-15%, — 6-12% R 2 O (Na 2 O + K 2 O) 13.0-17%, P 2 O 5 0-3%, — 0-2% Total iron (Fe 2 O 3 ) 0-15%, — 2-3% B 2 O 3 0-8%, — 0-4% TiO 2 0-3%,
  • compositions may include up to 2 or 3% of compounds to be considered as unanalysed impurities, as is known in this kind of composition.
  • the compositions have the remarkable property of being fiberizable over a very wide temperature range and furthermore endow the fibres obtained with biosolubility at acid pH.
  • the alkali content is preferably greater than 12%, especially greater than 13.0% and even 13.3%, and/or preferably less than 15%, especially less than 14.5%.
  • the compositions have iron oxide contents of between 5 and 12%, especially between 5 and 8%, which may allow mineral-wool blankets to exhibit fire resistance.
  • compositions satisfy the ratio:
  • the compositions according to the invention preferably have a lime content of between 10 and 25%, especially greater than 12%, preferably greater than 15% and/or preferably less than 23%, especially less than 20%, and even less than 17%, combined with a magnesia content of between 0 and 5%, with preferably less than 2% magnesia, especially less than 1% magnesia and/or a magnesia content of greater than 0.3%, especially greater than 0.5%.
  • the magnesia content is between 5 and 10% for a lime content of between 5 and 15%, and preferably between 5 and 10%.
  • Adding P 2 O 5 may allow the biosolubility at neutral pH to be increased.
  • the composition may also contain boron oxide which may allow the thermal properties of the mineral wool to be improved, especially by tending to lower its coefficient of thermal conductivity in the radiative component and also to increase the biosolubility at neutral pH.
  • TiO 2 may also be included in the composition, for example up to 3%.
  • Other oxides, such as BaO, SrO, MnO, Cr 2 O 3 and ZrO 2 may be present in the composition, each up to contents of approximately 2%.
  • the difference between the temperature corresponding to a viscosity of 10 2.5 poise (decipascal.second), denoted T log2.5 , and the liquidus of the crystallizing phase, denoted T liq , is preferably at least 10° C. for these compositions.
  • This difference, T log2.5 ⁇ T liq defines the “working range” of the compositions of the invention, that is to say the range of temperatures within which it is possible to fiberize, most particularly by internal centrifuging.
  • This difference is preferably at least 20 or 30° C., and even more than 50° C., especially more than 100° C.
  • the invention can be carried out in various advantageous ways depending on the choice of the composition of the alloy.
  • Nickel present in the alloy in the form of a solid solution as element for stabilizing the crystal structure of the cobalt, is used within the usual range of proportions of about 6 to 12%, advantageously 8 to 10%, by weight of the alloy.
  • Chromium contributes to the intrinsic mechanical strength of the matrix in which it is partly present in solid solution, but also in the form of carbides, essentially of the Cr 23 C 6 type, finely dispersed within the grains where they provide resistance to intragranular creep. It may also contribute to intergranular reinforcement of the alloy in the form of carbides of the Cr 7 C 3 or Cr 23 C 6 type, present at the grain boundaries, which prevent grain-over-grain slip. A heat treatment explained in detail below allows the Cr 7 C 3 carbides to be converted into Cr 23 C 6 carbides which are more stable at high temperature. Chromium contributes to the corrosion resistance as precursor of the chromium oxide which forms a protective layer on the surface exposed to the oxidizing medium.
  • a minimum amount of chromium is needed to form and maintain this protective layer.
  • too high a chromium content is deleterious to mechanical strength and to toughness at high temperatures as it results in too high a stiffness and too low a ductility incompatible with the high-temperature stresses.
  • the chromium content of an alloy that can be used according to the invention will be from 23 to 34% by weight, preferably about 26 to 32% by weight and advantageously around 28 to 30% by weight.
  • Tantalum is present in solid solution in the cobalt matrix, tantalum being a heavy atom which locally distorts the crystal lattice and impedes, or even blocks, the movement of dislocations when the material is subjected to a mechanical load, thus contributing to the intrinsic strength of the matrix. It is furthermore capable of forming, with carbon, TaC carbides present firstly as a fine dispersion within the grains, where they prevent intragranular creep, and secondly at the grain boundaries, where they provide intergranular reinforcement, possibly complemented by chromium carbides.
  • the minimum tantalum content making it possible to achieve the mechanical strength at very high temperature according to the invention is about 3%, the upper limit possibly being chosen around 10%.
  • the tantalum content is preferably about 4 to 10%, particularly 4.2 to 10%, very advantageously 4.5 to 10% and more particularly 5 to 10%.
  • the amount of tantalum is more advantageously about 5.5 to 9%, especially around 6 to 8.5%, by weight.
  • Carbon is an essential constituent of the alloy, needed to form metal carbide precipitates.
  • the carbon content directly determines the amount of carbides present in the alloy. It is at least 0.2% in order to obtain the minimum desired reinforcement, but is limited to at most 1.2% in order to prevent the alloy from becoming hard and difficult to machine because of too high a density of reinforcements.
  • the lack of ductility of the alloy with such contents prevents it from withstanding, without fracturing, an imposed strain (for example of thermal origin) and from resisting crack propagation sufficiently.
  • the carbon content is about 0.3 to 1.1% by weight and preferably about 0.35 to 1.05% by weight.
  • the composition of the alloy is adjusted so as to have a significant amount of tantalum carbides present at the grain boundaries.
  • the composition of the alloy is such that all the intergranular carbides are tantalum carbides. This may be achieved by choosing a tantalum content high enough to shift the carbide formation reactions in favour of TaC formation.
  • tantalum and carbon contents are advantageously chosen so that the Ta/C molar ratio is greater than or equal to 0.9, and is preferably around 1 to 1.2.
  • the TaC tantalum carbides are remarkably stable at high temperature since the inventors have observed, in metallographic sections that the structure of these carbides is hardly affected by being exposed to a high temperature of about 1300° C. Only a slight “dissolution” of the TaC carbides probably starting from Ta and C in the matrix can be observed, with no consequence on the mechanical properties. Thus, an alloy whose intergranular reinforcement consists only of TaC tantalum carbides guarantees the perpetuity of the reinforcement under extreme operating conditions at very high temperatures.
  • the tantalum carbides also contribute to the oxidation resistance of the alloy under such conditions as, by partially oxidizing into Ta 2 O 5 particles, they form, at the grain boundaries, clusters which act as plugs, preventing penetration of the oxidizing medium into the material.
  • the oxidizing medium is maintained at the surface of the tool, where it would seem the protective chromium oxide layer retains its good adhesion to the base alloy owing to the formation in the surface region of the spinner dish of Ta 2 O 5 which favours bonding of Cr 2 O 3 to the alloy.
  • the carbon content is advantageously around 0.3 to 0.55%, preferably around 0.35 to 0.5%, by weight of the alloy.
  • the alloy composition is such that the intergranular carbides do not only comprise tantalum carbides, these however being present in quite a large amount. This may be achieved by choosing a relatively high carbon content so that the proportion of TaC with respect to all the intergranular carbides gives the desired amount of tantalum carbide.
  • the carbon content is about 0.8 to 1.2%, preferably about 0.9 to 1.1% and particularly around 0.95 to 1%.
  • the intergranular carbide network is very dense but does not prove to be prejudicial for use at high temperature, greater than 1150° C. This is because above this temperature some of the M 23 C 6 carbides tend to dissolve in solid solution so that the intergranular precipitated phase gradually becomes discontinuous and actively impedes crack propagation.
  • a tantalum-to-carbon Ta/C molar ratio of less than 0.9 may then be as low as 0.3, preferably 0.35, the proportion of TaC among all the intergranular carbides being about 50% by volume, the rest consisting of carbides of the M 23 C 6 type where M is essentially chromium.
  • the Ta/C molar ratio is about 0.35 to 0.45.
  • the intergranular reinforcement remains effective at 1200-1300° C. because of the presence of a sufficient amount of TaC which are intact or oxidized to Ta 2 O 5 .
  • the presence of chromium at the grain boundaries constitues a source of chromium diffusion useful for corrosion resistance.
  • Tungsten may optionally be present in the alloy of the spinner dish. It is is then in solid solution in the matrix, where it improves the intrinsic mechanical strength by an effect whereby the cobalt crystal lattice is distorted. It may also together with chromium help to form intergranular M 23 C 6 carbides (which are then referred to as (Cr,W) 23 C 6 ) when the Ta/C molar ratio is less than 0.9.
  • alloys containing tungsten have a microstructure which reveals the formation of a new intergranular phase consisting of one of the TCP (Topologically Close Compact) phases—the ⁇ -CoCr phase—which embrittle the alloy.
  • This phase is formed because of an excessively high concentration of elements supposed to pass into solution in the crystallised cobalt. Since the alloys according to the invention are already characterized by a relatively high proportion of tantalum, the additional presence of tungsten together with chromium, nickel and carbon would force some of the elements of the matrix to combine in the grain boundaries or even in the matrix.
  • a preferred process according to the invention uses a tungsten-free alloy or an alloy substantially free of tungsten, it being understood that a minor amount of tungsten may be tolerated of the order of the amount of traces of a metallic impurity generally admitted in the metallurgical sense.
  • This alloy is particularly preferred for very high working temperatures, especially when the mineral composition enters the spinner dish at a temperature of at least 1150° C., particularly if the mineral composition has a liquidus temperature of 1140° C. or higher.
  • this alloy also exhibits interesting mechanical properties at a lower temperature, of the order of 1000° C. in the spinner dish, especially an improved creep resistance that allows new fiberizing conditions as far as the dimensions of the spinner dish or the speed of rotation of the dish are concerned.
  • the tungsten-free alloy is exclusively reinforced by tantalum carbide and suffers only a slight modification to the density of intergranular reinforcement.
  • the alloy may contain other standard constitutents or inevitable impurities. in general, it includes:
  • silicon as a deoxidizer for the molten metal during smelting and casting of the alloy, in an amount of less than 1% by weight;
  • manganese which is also a deoxidizer, in amount of less than 0.5% by weight;
  • zirconium for trapping undesirable elements such as sulphur or lead, in an amount of less then 0.1% by weight;
  • iron in an amount possibly up to 3% by weight without impairing the properties of the material
  • the cumulative amount of the other elements introduced as impurities with the essential constituents of the alloy advantageously represents less than 1% by weight of the composition of the alloy.
  • the alloys according to the invention preferably contain no B, Hf, Y, Dy, Re and other rare earths.
  • the subject of the invention is a cobalt-based alloy exhibiting high-temperature mechanical strength in an oxidizing medium, which also includes chromium, nickel, tantalum and carbon, characterized in that it does not contain tungsten and in that it is essentially composed of the following elements (the proportions being indicated as percentages by weight of the alloy): Cr 23 to 34% Ni 6 to 12% Ta 3 to 10% C 0.2 to 1.2% Fe less than 3% Si less than 1% Mn less than 0.5% Zr less than 0.1%,
  • the balance consisting of cobalt and inevitable impurities and the Ta/C molar ratio being at least 0.3, preferably at least 0.35.
  • This alloy according to the invention is essentially characterized by a high tantalum content and the absence of tungsten. This makes it possible to form reinforcing phases which are precipitated or in solid solution, are mainly based on tantalum and ensure high strength at high temperature.
  • the chromium, nickel and carbon contents may be chosen to be within the advantageous ranges indicated above.
  • the tantalum content is preferably about 4 to 10%, particularly 4.2 to 10% and very advantageously 4.5 to 10%.
  • the Ta/C molar ratio is greater than or equal to 0.9; advantageously, it is about 1 to 1.2.
  • the carbon content is therefore advantageously from 0.3 to 0.55%, preferably around 0.35 to 0.5%, by weight.
  • the carbon content is about 0.8 to 1.2%, preferably 0.9 to 1% and particularly around 0.95 to 1%.
  • the Ta/C molar ratio is then advantageously from 0.3 to 0.5, advantageously from 0.35 to 0.45.
  • tungsten-free alloys are particularly appreciated for carrying out a process at high temperature, of at least 1150 to 1200° C., but they can, of course, be employed in more standard processes for manufacturing mineral wool in which the spinner dish is heated to a temperature of about 900 to 1100° C.
  • the subject of the invention is also another cobalt-based alloy which comprises the following elements: Cr 23 to 34% Ni 6 to 12% Ta 4.2 to 10% W 4 to 8% C 0.8 to 1.2% Fe less than 3% Si less than 1% Mn less than 0.5% Zr less than 0.1%,
  • the balance consisting of cobalt and inevitable impurities and the Ta/C molar ratio being at least 0.3, preferably about 0.3 to 0.5, advantageously at least 0.35 and in particular from 0.35 to 0.45.
  • the chromium, nickel, tantalum and carbon contents may be chosen to be within the advantageous ranges indicated above.
  • the alloys that can be used according to the invention when they contain no highly reactive elements such as B, Hf and rare earths, including Y, Dy, Re, may be very easily formed by conventional melting and casting using standard means, especially by inductive melting, in at least partially inert atmosphere, and casting into a sand mould.
  • These alloys containing a certain proportion of tungsten are less preferred than the previous alloys as they make it possible instead to work around 1100 to 1150° C. As previously, they may be used in processes in which the tool is heated to a temperature of 900 to 1100° C.
  • a particular microstructure may advantageously be achieved by a two-step heat-treatment which makes it possible, in particular, to convert the M 7 C 3 -type carbides into M 23 C 6 carbides:
  • a solution phase which comprises annealing at a temperature of 1100 to 1250° C., especially about 1200 to 1250° C., in particular for a time possibly of between 1 and 4 hours, advantageously about 2 hours;
  • a carbide precipitation phase which comprises annealing at a temperature of 850 to 1050° C., especially about 1000° C., in particular for a time possibly ranging from 5 to 20 hours, advantageously about 10 hours.
  • the subject of the invention is also a process for manufacturing, in a foundry, an article from the alloys described above as subject of the invention, possibly with the above heat-treatment steps.
  • the process may include at least one cooling step, after the casting operation and/or after the first heat-treatment phase, and after the heat treatment.
  • the intermediate and/or final cooling steps may be carried out for example, by air cooling, especially with the temperature returning to ambient temperature.
  • the process may furthermore include a forging step after the casting operation.
  • the alloys forming the subject of the invention can be used to manufacture all kinds of components mechanically stressed at high temperature and/or made to work in an oxidizing or corrosive environment.
  • the subject of the invention is also such articles manufactured from an alloy according to the invention, especially by foundrywork.
  • the invention may be applied to the manufacture of a very wide range of articles when these have to exhibit high mechanical strength in an oxidizing and/or corrosive environment, particularly at high temperature.
  • these alloys can be used to produce any type of fixed or moving component made of refractory alloy serving in the operation or running of a high-temperature heat treatment furnace (operating above 1100° C.), a heat exchanger or a reactor for the chemical industry.
  • they may, for example, be hot fan blades, firing supports, furnace-charging equipment, etc.
  • They may also be used to produce any type of resistance heating element intended to operate in a hot oxidizing atmosphere, and to produce turbine components, used in the engines of land-based, seagoing or airborne vehicles, or in any other application not aimed at vehicles, for example in power stations.
  • the subject of the invention is the use, in an oxidizing atmosphere at a temperature of at least 1100° C., of an article made of a cobalt alloy as defined above.
  • FIG. 1 shows a micrograph of the structure of an alloy according to the invention
  • FIG. 2 is a graph illustrating the mechanical properties of this alloy
  • FIGS. 3 and 4 show micrographs of the structure of a comparative alloy
  • FIGS. 5 and 6 are graphs comparing the mechanical properties of various alloys
  • FIG. 7 shows a micrograph of the structure of another alloy used according to the invention.
  • the microstructure of the alloy obtained is composed of a cobalt matrix with a face-centred cubic structure, stablized by the presence of nickel, including, in solid solution, chromium and tantalum, with carbide precipitates present within the grains and at the grain boundaries.
  • FIG. 1 shows a view of the alloy in a scanning electron microscope (SEM) with a magnification of 250: the grain boundaries, which do not appear in the micrograph with the magnification used, have been depicted by the thin lines 1.
  • the intragranular phase consists of fine secondary carbides 2 of the Cr 23 C 6 and TaC types, precipitated uniformly in the matrix and appearing in the form of small specks.
  • the grain boundaries there is a dense but discontinuous intergranular phase composed exclusively of tantalum carbides (TaC) 3 which appear as well-separated islands of generally elongate shape.
  • This microstructure is due to the tantalum-to-carbon molar ratio in the composition of the alloy, which is equal to 1.07.
  • the alloy exhibits excellent creep properties at 1200° C. and 1250° C. and even appreciable creep resistance at 1300° C. under the load applied.
  • oxidation resistance properties were evaluated in thermogravimetric tests at 1200° C.: a parabolic oxidation constant K p of 96.5 ⁇ 10 ⁇ 12 g 2 .cm ⁇ 4 .s ⁇ 1 and a parabolic evaporation constant K v of 3.96 ⁇ 10 ⁇ 19 g.cm ⁇ 2. s ⁇ 1 were obtained.
  • the spinner dish was used with an output of 2.3 metric tons per day until it was decided to stop it after the spinner dish was deemed to be ruined as demonstrated by visible damage or by the quality of the fibre produced becoming not high enough.
  • the temperature of the mineral composition entering the spinner dish was about 1200 to 1240° C.
  • the temperature of the metal along the profile of the spinner dish was between 1160 and 1210° C.
  • the lifetime (in hours) of the spinner dish thus measured was 390 hours.
  • the long withstand time of the spinner dish is due to the good creep resistance of the alloy at 1200° C. under moderate stress (the mechanical conditions resulting from the geometry of the spinner dish).
  • the microstructure of this alloy illustrated in FIG. 3, shows the presence at the grain boundaries of about 50% of (Cr,W) 23 C 6 carbides (visible at 4 in the form of thin eutectic areas) and 50% of TaC carbides (visible at 3).
  • FIGS. 5 and 6 and Table 1 also show the high-temperature mechanical properties of another comparative alloy of a different type: this is an ODS-type super alloy which has a matrix consisting of nickel-chromium and is reinforced by an oxide phase, such as yttrium oxide.
  • the grade tested in Comparative Example 2 is MA 758 from Special Metals.
  • the ODS alloy of Comparative Example 2 has a much better creep resistance than the cobalt alloy of Comparative Example 1: the slope of the creep curve at 1200° C. is fifteen times greater in the case of the cobalt-based comparative alloy.
  • Example 1 remains inferior to the ODS alloy, having a creep curve slope at 1200° C. two to three times greater, but this constitutes a considerable improvement over the alloy of Comparative Example 1.
  • Example 1 Another alloy according to the invention was prepared as in Example 1 and its properties were evaluated in the same way, the said alloy having the following composition: Cr 28.5% Ni 8.9% C 0.5% Ta 8.5% W 0% Residuals: Fe ⁇ 3% Si ⁇ 1% Mn ⁇ 0.5% Zr ⁇ 0.1% Others (combined) ⁇ 1%,
  • Example 2 Another alloy according to the invention was prepared as in Example 1 and its properties were evaluated in the same way, the said alloy having the following composition: Cr 29% Ni 8.86% C 0.98% Ta 6% W 0% Residuals: Fe ⁇ 3% Si ⁇ 1% Mn ⁇ 0.5% Zr ⁇ 0.1% Others (combined) ⁇ 1%,
  • FIG. 7 shows a view obtained in a scanning electron microscope, reveals quite a dense intergranular network of eutectic tantalum carbides (TaC) 6 with the cobalt solid solution.
  • TaC eutectic tantalum carbides
  • the microstructure clearly shows a phase 7 in the form of dispersed compact areas rich in cobalt and in chromium in almost equal parts, which consist of one of the TCP (Topologically Close Compact) phases—the ⁇ -CoCr phase known to embrittle the alloy.
  • TCP Topicologically Close Compact

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Inorganic Fibers (AREA)
  • Manufacture, Treatment Of Glass Fibers (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Glass Compositions (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Spinning Or Twisting Of Yarns (AREA)
US10/276,316 2000-05-23 2001-05-23 Method for making mineral wool, cobalt-based alloys therefor and other uses Abandoned US20040050114A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US11/843,949 US8398791B2 (en) 2000-05-23 2007-08-23 Process for manufacturing mineral wool, cobalt-based alloys for the process and other uses

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR00/06583 2000-05-23
FR0006583A FR2809387B1 (fr) 2000-05-23 2000-05-23 Procede de fabrication de laine minerale, alliages a base de cobalt pour le procede et autres utilisations
PCT/FR2001/001590 WO2001090429A1 (fr) 2000-05-23 2001-05-23 Procede de fabrication de laine minerale, alliages a base de cobalt pour le procede et autres utilisations

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US11/843,949 Division US8398791B2 (en) 2000-05-23 2007-08-23 Process for manufacturing mineral wool, cobalt-based alloys for the process and other uses

Publications (1)

Publication Number Publication Date
US20040050114A1 true US20040050114A1 (en) 2004-03-18

Family

ID=8850524

Family Applications (2)

Application Number Title Priority Date Filing Date
US10/276,316 Abandoned US20040050114A1 (en) 2000-05-23 2001-05-23 Method for making mineral wool, cobalt-based alloys therefor and other uses
US11/843,949 Expired - Fee Related US8398791B2 (en) 2000-05-23 2007-08-23 Process for manufacturing mineral wool, cobalt-based alloys for the process and other uses

Family Applications After (1)

Application Number Title Priority Date Filing Date
US11/843,949 Expired - Fee Related US8398791B2 (en) 2000-05-23 2007-08-23 Process for manufacturing mineral wool, cobalt-based alloys for the process and other uses

Country Status (27)

Country Link
US (2) US20040050114A1 (hu)
EP (1) EP1287174B1 (hu)
JP (1) JP4991077B2 (hu)
KR (1) KR100781181B1 (hu)
CN (1) CN1210423C (hu)
AR (1) AR035335A1 (hu)
AT (1) ATE296902T1 (hu)
AU (2) AU2001264007B2 (hu)
BR (1) BR0111092B1 (hu)
CA (1) CA2410309C (hu)
CZ (1) CZ304717B6 (hu)
DE (1) DE60111216T2 (hu)
DK (1) DK1287174T3 (hu)
ES (1) ES2243501T3 (hu)
FR (1) FR2809387B1 (hu)
HR (1) HRP20020928B1 (hu)
HU (1) HU228380B1 (hu)
IS (1) IS2193B (hu)
NO (1) NO338387B1 (hu)
NZ (1) NZ522176A (hu)
PL (1) PL196192B1 (hu)
PT (1) PT1287174E (hu)
RU (1) RU2255131C2 (hu)
SK (1) SK286499B6 (hu)
UA (1) UA78681C2 (hu)
WO (1) WO2001090429A1 (hu)
ZA (1) ZA200208481B (hu)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2004293617B2 (en) * 2003-11-26 2010-03-11 Saint-Gobain Isover Refractory alloy and mineral wool production method
US20210332460A1 (en) * 2019-03-07 2021-10-28 Mitsubishi Power, Ltd. Cobalt based alloy product and cobalt based alloy article
US11261506B2 (en) 2017-02-28 2022-03-01 Saint-Gobain Seva Alloy for a fibre-forming plate
US11306372B2 (en) 2019-03-07 2022-04-19 Mitsubishi Power, Ltd. Cobalt-based alloy powder, cobalt-based alloy sintered body, and method for producing cobalt-based alloy sintered body
US11325189B2 (en) 2017-09-08 2022-05-10 Mitsubishi Heavy Industries, Ltd. Cobalt based alloy additive manufactured article, cobalt based alloy product, and method for manufacturing same
US11414728B2 (en) 2019-03-07 2022-08-16 Mitsubishi Heavy Industries, Ltd. Cobalt based alloy product, method for manufacturing same, and cobalt based alloy article
US11427893B2 (en) * 2019-03-07 2022-08-30 Mitsubishi Heavy Industries, Ltd. Heat exchanger
US11499208B2 (en) * 2019-03-07 2022-11-15 Mitsubishi Heavy Industries, Ltd. Cobalt based alloy product
US11613795B2 (en) 2019-03-07 2023-03-28 Mitsubishi Heavy Industries, Ltd. Cobalt based alloy product and method for manufacturing same

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2924442B1 (fr) * 2007-11-30 2010-02-26 Saint Gobain Isover Alliage refractaire, assiette de fibrage et procede de fabrication de laine minerale
CN102161567B (zh) * 2011-03-04 2012-12-26 山东鑫海科技股份有限公司 利用矿热电炉冶炼镍合金熔融废渣显热生产矿棉纤维的方法
RU2567913C1 (ru) * 2014-09-24 2015-11-10 Общество с ограниченной ответственностью "СМП - Механика" Фильерный питатель
FR3042187B1 (fr) * 2015-10-08 2023-08-25 Saint Gobain Isover Fibres minerales
US11492682B2 (en) * 2017-03-14 2022-11-08 Vbn Components Ab High carbon content cobalt-based alloy
ES2913751T3 (es) * 2017-11-20 2022-06-06 Stm Tech S R L Aleación a base de cobalto con una alta resistencia a altas temperaturas, hiladora para la producción de fibras minerales que comprende dicha aleación y procedimiento para la producción de fibras minerales que usa una hiladora de este tipo
EP3677697A1 (en) * 2019-01-07 2020-07-08 Siemens Aktiengesellschaft Co-alloy for additive manufacturing and method
CN113582536B (zh) * 2021-08-20 2023-08-01 山东鲁阳节能材料股份有限公司 一种可溶性矿物纤维毯的制备方法及制备系统

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3933484A (en) * 1974-05-31 1976-01-20 Owens-Corning Fiberglas Corporation Cobalt-base alloy
US4668265A (en) * 1985-06-18 1987-05-26 Owens-Corning Fiberglas Corporation Corrosion resistant cobalt-base alloy and method of making fibers
US4904290A (en) * 1988-09-30 1990-02-27 Owens-Corning Fiberglas Corporation Cobalt based alloys with critical carbon content for making and using in glass fiber production
US5176729A (en) * 1990-10-29 1993-01-05 Isover Saint-Gobain Method of producing fibers by internal centrifugation and the application of the said method to the drawing out of certain glasses into fibers
US6284684B1 (en) * 1998-09-17 2001-09-04 Isover Saint Gobain Mineral wool composition
US6897173B2 (en) * 2000-03-17 2005-05-24 Saint-Gobain Isover Mineral wool composition

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3366478A (en) * 1965-07-21 1968-01-30 Martin Marietta Corp Cobalt-base sheet alloy
JPS60224732A (ja) * 1984-04-19 1985-11-09 Mitsubishi Metal Corp Ｃｏ基耐熱合金
JPS60224731A (ja) * 1984-04-19 1985-11-09 Mitsubishi Metal Corp Ｃｏ基耐熱合金
JPS6240392A (ja) * 1985-08-16 1987-02-21 Nippon Steel Corp 鋼帯巾方向差厚電気メツキ方法
JPH06240392A (ja) * 1992-12-21 1994-08-30 Mitsubishi Materials Corp 耐摩耗性のすぐれたＣｏ基合金製ガラス繊維成形スピナー
CA2133061A1 (en) * 1993-02-05 1994-08-18 Jean L. Bernard Spinnner for producing fibers by centrifugation of molten mineral material shaped as a single crystal coating and process for its manufacture
FR2769024A1 (fr) * 1997-09-29 1999-04-02 Saint Gobain Isover Alliage a base de cobalt, article realise a partir de l'alliage et son procede de fabrication
FR2778399A1 (fr) * 1998-05-06 1999-11-12 Saint Gobain Isover Composition de laine minerale

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3933484A (en) * 1974-05-31 1976-01-20 Owens-Corning Fiberglas Corporation Cobalt-base alloy
US4668265A (en) * 1985-06-18 1987-05-26 Owens-Corning Fiberglas Corporation Corrosion resistant cobalt-base alloy and method of making fibers
US4904290A (en) * 1988-09-30 1990-02-27 Owens-Corning Fiberglas Corporation Cobalt based alloys with critical carbon content for making and using in glass fiber production
US5176729A (en) * 1990-10-29 1993-01-05 Isover Saint-Gobain Method of producing fibers by internal centrifugation and the application of the said method to the drawing out of certain glasses into fibers
US6284684B1 (en) * 1998-09-17 2001-09-04 Isover Saint Gobain Mineral wool composition
US6897173B2 (en) * 2000-03-17 2005-05-24 Saint-Gobain Isover Mineral wool composition

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2004293617B2 (en) * 2003-11-26 2010-03-11 Saint-Gobain Isover Refractory alloy and mineral wool production method
US11261506B2 (en) 2017-02-28 2022-03-01 Saint-Gobain Seva Alloy for a fibre-forming plate
US11325189B2 (en) 2017-09-08 2022-05-10 Mitsubishi Heavy Industries, Ltd. Cobalt based alloy additive manufactured article, cobalt based alloy product, and method for manufacturing same
US20210332460A1 (en) * 2019-03-07 2021-10-28 Mitsubishi Power, Ltd. Cobalt based alloy product and cobalt based alloy article
US11306372B2 (en) 2019-03-07 2022-04-19 Mitsubishi Power, Ltd. Cobalt-based alloy powder, cobalt-based alloy sintered body, and method for producing cobalt-based alloy sintered body
US11414728B2 (en) 2019-03-07 2022-08-16 Mitsubishi Heavy Industries, Ltd. Cobalt based alloy product, method for manufacturing same, and cobalt based alloy article
US11427893B2 (en) * 2019-03-07 2022-08-30 Mitsubishi Heavy Industries, Ltd. Heat exchanger
US11499208B2 (en) * 2019-03-07 2022-11-15 Mitsubishi Heavy Industries, Ltd. Cobalt based alloy product
US11613795B2 (en) 2019-03-07 2023-03-28 Mitsubishi Heavy Industries, Ltd. Cobalt based alloy product and method for manufacturing same

Also Published As

Publication number Publication date
KR20030001516A (ko) 2003-01-06
DK1287174T3 (da) 2005-10-03
AU2001264007B2 (en) 2005-05-05
NO20025548D0 (no) 2002-11-19
US8398791B2 (en) 2013-03-19
IS6597A (is) 2002-10-28
KR100781181B1 (ko) 2007-12-03
HRP20020928B1 (hr) 2011-07-31
CZ304717B6 (cs) 2014-09-10
UA78681C2 (uk) 2007-04-25
SK16272002A3 (sk) 2003-05-02
ES2243501T3 (es) 2005-12-01
AR035335A1 (es) 2004-05-12
ZA200208481B (en) 2004-03-11
FR2809387A1 (fr) 2001-11-30
BR0111092A (pt) 2003-04-08
FR2809387B1 (fr) 2002-12-20
HU228380B1 (en) 2013-03-28
DE60111216D1 (de) 2005-07-07
JP2003535970A (ja) 2003-12-02
WO2001090429A1 (fr) 2001-11-29
RU2255131C2 (ru) 2005-06-27
PL358176A1 (en) 2004-08-09
AU6400701A (en) 2001-12-03
CN1430681A (zh) 2003-07-16
PT1287174E (pt) 2005-10-31
NO338387B1 (no) 2016-08-15
BR0111092B1 (pt) 2009-05-05
CA2410309C (fr) 2010-11-09
HRP20020928A2 (en) 2005-02-28
CA2410309A1 (fr) 2001-11-29
CN1210423C (zh) 2005-07-13
EP1287174A1 (fr) 2003-03-05
EP1287174B1 (fr) 2005-06-01
SK286499B6 (sk) 2008-11-06
IS2193B (is) 2007-01-15
NZ522176A (en) 2005-05-27
PL196192B1 (pl) 2007-12-31
NO20025548L (no) 2002-11-19
US20070292303A1 (en) 2007-12-20
HUP0302040A2 (hu) 2003-09-29
DE60111216T2 (de) 2006-04-27
ATE296902T1 (de) 2005-06-15
HUP0302040A3 (en) 2010-12-28
JP4991077B2 (ja) 2012-08-01

Similar Documents

Publication Publication Date Title
US8398791B2 (en) Process for manufacturing mineral wool, cobalt-based alloys for the process and other uses
KR910009875B1 (ko) 고강도를 갖는 유리부식 저항성 코발트 기초합금
CN112771187A (zh) 纤维板用合金
US11261506B2 (en) Alloy for a fibre-forming plate
AU749803B2 (en) Cobalt based alloy, article made from said alloy and method for making same
US8262964B2 (en) Refractory alloy, fibre-forming plate and method for producing mineral wool
ZA200604128B (en) Refractory alloy and mineral wool production method
US20030221756A1 (en) Cobalt based alloy, article made from said alloy and method for making same
BRPI0819639B1 (pt) League, article and form of fiber formation for the manufacture of mineral wool and process of manufacture of mineral wool.

Legal Events

Date Code Title Description
AS Assignment

Owner name: SAINT-GOBAIN ISOVER, FRANCE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BERTHOD, PATRICE;BERNARD, JEAN-LUC;LIEBAUT, CHRISTOPHE;REEL/FRAME:014458/0924;SIGNING DATES FROM 20021125 TO 20021216

Owner name: SAINT-GOBAIN SEVA, FRANCE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BERTHOD, PATRICE;BERNARD, JEAN-LUC;LIEBAUT, CHRISTOPHE;REEL/FRAME:014458/0924;SIGNING DATES FROM 20021125 TO 20021216

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION