US20070044873A1 - Fine grain niobium sheet via ingot metallurgy - Google Patents

Fine grain niobium sheet via ingot metallurgy Download PDF

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Publication number
US20070044873A1
US20070044873A1 US11/216,498 US21649805A US2007044873A1 US 20070044873 A1 US20070044873 A1 US 20070044873A1 US 21649805 A US21649805 A US 21649805A US 2007044873 A1 US2007044873 A1 US 2007044873A1
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wrought product
niobium
annealing
blend
wrought
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US11/216,498
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Paul Aimone
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Materion Newton Inc
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HC Starck Inc
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Priority to US11/216,498 priority Critical patent/US20070044873A1/en
Assigned to H. C. STARCK INC. reassignment H. C. STARCK INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: AIMONE, PAUL R.
Priority to EP11177827.0A priority patent/EP2388345B1/en
Priority to CN200680030944A priority patent/CN101680055A/en
Priority to AT06813595T priority patent/ATE541063T1/en
Priority to EP11177836.1A priority patent/EP2388346B1/en
Priority to PCT/US2006/032578 priority patent/WO2007027466A2/en
Priority to CA002619813A priority patent/CA2619813A1/en
Priority to RU2008111870/02A priority patent/RU2008111870A/en
Priority to MX2008002746A priority patent/MX2008002746A/en
Priority to EP06813595A priority patent/EP1924718B1/en
Priority to JP2008529106A priority patent/JP2009506219A/en
Priority to TW095131878A priority patent/TW200722205A/en
Publication of US20070044873A1 publication Critical patent/US20070044873A1/en
Assigned to DRESDNER BANK AG, NIEDERLASSUNG LUXEMBOURG, AS SECURITY AGENT reassignment DRESDNER BANK AG, NIEDERLASSUNG LUXEMBOURG, AS SECURITY AGENT INTELLECTUAL PROPERTY RIGHTS SECURITY AGREEMENT (MEZZANINE) Assignors: H.C. STARCK INC.
Assigned to DRESDNER BANK AG, NIEDERLASSUNG LUXEMBOURG, AS SECURITY AGENT reassignment DRESDNER BANK AG, NIEDERLASSUNG LUXEMBOURG, AS SECURITY AGENT INTELLECTUAL PROPERTY RIGHTS SECURITY AGREEMENT (SENIOR) Assignors: H.C. STARCK INC.
Assigned to DRESDNER BANK AG, NIEDERLASSUNG LUXEMBOURG, AS SECURITY AGENT reassignment DRESDNER BANK AG, NIEDERLASSUNG LUXEMBOURG, AS SECURITY AGENT INTELLECTUAL PROPERTY RIGHTS SECURITY AGREEMENT (SECOND LIEN) Assignors: H.C. STARCK INC.
Priority to NO20081363A priority patent/NO20081363L/en
Priority to US13/463,024 priority patent/US9255309B2/en
Assigned to GLAS TRUST CORPORATION LIMITED, AS SECURITY AGENT FOR THE BENEFIT OF THE SECOND LIEN SECURED PARTIES reassignment GLAS TRUST CORPORATION LIMITED, AS SECURITY AGENT FOR THE BENEFIT OF THE SECOND LIEN SECURED PARTIES SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: H.C. STARCK INC.
Assigned to GLAS TRUST CORPORATION LIMITED, AS SECURITY AGENT FOR THE BENEFIT OF THE SENIOR SECURED PARTIES reassignment GLAS TRUST CORPORATION LIMITED, AS SECURITY AGENT FOR THE BENEFIT OF THE SENIOR SECURED PARTIES SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: H.C. STARCK INC.
Assigned to H.C. STARCK INC. reassignment H.C. STARCK INC. RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: GLAS TRUST CORPORATION LIMITED
Assigned to H.C. STARCK INC. reassignment H.C. STARCK INC. RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: GLAS TRUST CORPORATION LIMITED
Assigned to H.C. STARCK INC. reassignment H.C. STARCK INC. RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: GLAS TRUST CORPORATION LIMITED
Assigned to H.C. STARCK INC. reassignment H.C. STARCK INC. RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: GLAS TRUST CORPORATION LIMITED
Assigned to H.C. STARCK INC. reassignment H.C. STARCK INC. RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: GLAS TRUST CORPORATION LIMITED
Abandoned legal-status Critical Current

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Classifications

    • 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
    • C22B34/00—Obtaining refractory metals
    • C22B34/20—Obtaining niobium, tantalum or vanadium
    • C22B34/24—Obtaining niobium or tantalum
    • 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
    • C22B9/20—Arc remelting
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C27/00—Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
    • C22C27/02—Alloys based on vanadium, niobium, or tantalum
    • 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
    • C22F1/16—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon
    • C22F1/18—High-melting or refractory metals or alloys based thereon
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/34—Sputtering
    • C23C14/3407—Cathode assembly for sputtering apparatus, e.g. Target
    • C23C14/3414—Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H7/00—Details of devices of the types covered by groups H05H9/00, H05H11/00, H05H13/00
    • H05H7/14—Vacuum chambers
    • H05H7/18—Cavities; Resonators
    • H05H7/20—Cavities; Resonators with superconductive walls
    • 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
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps

Definitions

  • the present invention relates to a process for manufacturing niobium plates or sheets as well as uses thereof, such as for deep drawn cups and sputtering targets.
  • Niobium ingots can be rolled to plate and sheet dimensions using known methods in the art. Such plates and sheets can be used, for example, by being deep drawn into cups for the synthetic diamond industry.
  • the niobium foil used typically has an inconsistent and coarse grain size, which leads to poor flatness and smoothness of the deep drawn cup bottom. Poor flatness and/or smoothness (orange peel) result in a synthetic diamond that requires excessive grinding to correct deficiencies.
  • the problem ultimately relates to a coarse grain structure in the niobium sheet.
  • the coarse grain structure can also cause tearing of the sheet during deep-draw operations.
  • the grain size of typical, commercially available niobium sheet is variable, ranging from an ASTM grain size of from 4 to 10. It is, however, desirable to use niobium sheet with an ASTM grain size finer than 7.5 with at least 90% recrystallization for deep draw applications, although this still produces a high rejection rate for flatness and surface finish. An ASTM grain size finer than 8.0 with at least 90% recrystallization almost completely eliminates these issues.
  • niobium sheet having a consistent ASTM grain size and sufficient recrystallization to minimize or prevent flatness and/or smoothness problems with the sheet.
  • the present invention is directed to a method of making an alloy of niobium.
  • the method includes:
  • the present invention is also directed to a niobium containing wrought product prepared according to the above-described method.
  • the present invention is additionally directed to deep drawn cups and sputtering targets made from the modified niobium wrought product described above.
  • the present invention relates to a method for manufacturing niobium wrought products.
  • the method provides a significant reduction as well as better control of the final grain size in niobium wrought products. More particularly, the present invention provides niobium wrought products that contain greater than 5 ppm of the alloying metal, which has a consistently fine, uniform, and fully recrystallized grain structure.
  • the term “wrought products” refers generally to metals that have been exposed to thermo-mechanical processing steps to acquire a specific shape and/or other properties.
  • the thermal steps can include, but are not limited to annealing, baking, smelting and/or melting.
  • the mechanical steps can include, but are not limited to working, forging, rolling, upset forging, upset-and-forge-back techniques, hammer forging, drawback forging, flat forging, round forging, and radial forging.
  • Wrought products include, but are not limited to generally planar metal forms such as foils (less than about 10 mil in thickness), sheets (from about 10 to about 125 mil in thickness), and plates (greater than about 125 mil in thickness.
  • Other wrought product forms can include tubes, where a length of metal is hollow in the center (and can have any cross-sectional internal and external shape, but often those shapes will be circular, oval, square, rectangular, triangular, hexagonal, or octagonal); and rods, which are lengths of metal that are solid throughout and can have any cross-sectional internal and external shape, but often those shapes will be circular, oval, square, rectangular, triangular, hexagonal, or octagonal.
  • vacuum arc remelting is used to alloy niobium with low level metal additions along with traditional thermo-mechanical processing with higher annealing temperatures to produce niobium wrought products with a fine and fully recrystallized grain structure.
  • inventive process provides high yields, a more consistent product, and lower manufacturing costs.
  • the metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium is present at a level of at least 0.01 ppm, in some cases 0.1 ppm and as high as 60 ppm, in some cases 50 ppm based on the total niobium in the niobium ingot.
  • the amount of metal in the niobium can be any value or can range between any of the values recited above.
  • a blend containing niobium powder and a metal powder selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium is formed and pressed to form a pressed blend.
  • a metal powder selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium.
  • the term “pressed blend” refers to a solid form where a mixture of materials are compressed to form a stable shape, which is capable of being attached to another body, such that when the other body melts, the pressed blend melts and commingles with the elements of the other body.
  • the pressed blends are attached to electrodes that contain niobium using a suitable method and both are melted under vacuum arc remelting (VAR) conditions and subsequently cooled.
  • VAR vacuum arc remelting
  • the niobium acts as an electrode, and is melted by striking an arc between a charged electrode and the niobium, under vacuum.
  • the arc power can be from 25 to 50V and from 7,000 to 10,000 amps.
  • a pressed blend of niobium and the metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium is used with a niobium electrode.
  • the melted electrode and pressed blend is cooled to form an alloy ingot.
  • Thermo-mechanical processing steps as indicated above are applied to the alloy ingot to form a wrought product as described above.
  • the alloy ingot can be vacuum annealed at a temperature of at least 950° C. and up to 1150° C.
  • the annealing temperature for the wrought product can be any value or range between the values recited above.
  • the annealing step can take at least 5 minutes and up to 180 minutes.
  • the length of time for annealing can be any value or can range between any values recited above.
  • the annealing step can result in at least 75% recrystallization and in some cases up to at least 95% recrystallization.
  • sequential rolling and annealing steps can be carried out on the alloy ingot. Any suitable combination of rolling and annealing steps can be used. In a particular embodiment of the invention, the following steps are used:
  • the intermediate thickness 1) can be from 0.5 to 2 cm and the wrought product II) can have a thickness of from 0.005 to 0.24 cm.
  • thermo-mechanical processing steps in d) can include i) forging the alloy ingot to form a wrought product; and ii) annealing the wrought product at a temperature of from 950 to 1150° C.
  • annealing steps can result in at least 75% recrystallization and in some cases up to at least 95% recrystallization.
  • scrap niobium is consolidated via VAR, ISM, or other cold hearth melting techniques and the metal (selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium) addition made directly to the melt or via the VAR process described above.
  • the cooled, annealed plate and sheet has a fine and uniform ASTM grain size up to 10, and can be as coarse as 5.
  • the ASTM grain size is in the range of 8 to 10.
  • the present invention also provides for wrought product made according to the above described processes, where the wrought products are selected from a foil, a sheet, a plate, a tube, and a rod.
  • the present invention also provides for deep drawn cups or sputtering targets obtained using, made from, or including the above-described wrought products.
  • the metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium
  • niobium combines with niobium to form alloy particles in the niobium or possibly with oxygen to produce sub-micron size oxides of the respective metal added.
  • Rolling (cold working) to sheet produces a uniform dispersion of these particles that on subsequent annealing act initially as grain nucleation sites and, with continued annealing, as grain boundary pinning points.

Abstract

A method of making an alloy of niobium that includes: A) forming a blend comprising niobium powder and a powder of a metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium and pressing the blend to form pressed blend; B) attaching the pressed blend to an electrode comprising niobium; C) melting the electrode and pressed blend under vacuum arc remelting conditions, such that the blend mixes with the melted electrode; D) cooling the melted electrode to form an alloy ingot; and E) applying thermo-mechanical processing steps to the alloy ingot to form a wrought product. The method provides a fully recrystallized niobium wrought product with a grain size finer that ASTM 5, that can be used to make deep drawn cups and sputtering targets.

Description

    BACKGROUND OF THE INVENTION
  • The present invention relates to a process for manufacturing niobium plates or sheets as well as uses thereof, such as for deep drawn cups and sputtering targets.
  • Niobium ingots can be rolled to plate and sheet dimensions using known methods in the art. Such plates and sheets can be used, for example, by being deep drawn into cups for the synthetic diamond industry. The niobium foil used typically has an inconsistent and coarse grain size, which leads to poor flatness and smoothness of the deep drawn cup bottom. Poor flatness and/or smoothness (orange peel) result in a synthetic diamond that requires excessive grinding to correct deficiencies. The problem ultimately relates to a coarse grain structure in the niobium sheet. The coarse grain structure can also cause tearing of the sheet during deep-draw operations.
  • The grain size of typical, commercially available niobium sheet is variable, ranging from an ASTM grain size of from 4 to 10. It is, however, desirable to use niobium sheet with an ASTM grain size finer than 7.5 with at least 90% recrystallization for deep draw applications, although this still produces a high rejection rate for flatness and surface finish. An ASTM grain size finer than 8.0 with at least 90% recrystallization almost completely eliminates these issues.
  • It would be desirable to provide a method of producing niobium sheet having a consistent ASTM grain size and sufficient recrystallization to minimize or prevent flatness and/or smoothness problems with the sheet.
  • U.S. application Ser. No. 10/974,519, filed Oct. 27, 2004 describes a silicon-containing alloy of niobium that solves the above-identified problem.
    • DESCRIPTION OF THE INVENTION
  • The present invention is directed to a method of making an alloy of niobium. The method includes:
      • A) forming a blend comprising niobium powder and a powder of a metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium and pressing the blend to form pressed blend;
      • B) attaching the pressed blend to an electrode comprising niobium;
      • C) melting the electrode and pressed blend under vacuum arc remelting conditions, such that the blend mixes with the melted electrode;
      • D) cooling the melted electrode to form an alloy ingot; and
      • E) applying thermo-mechanical processing steps to the alloy ingot to form a wrought product.
  • The present invention is also directed to a niobium containing wrought product prepared according to the above-described method.
  • The present invention is additionally directed to deep drawn cups and sputtering targets made from the modified niobium wrought product described above.
  • Other than in the operating examples, or where otherwise indicated, all numbers or expressions referring to quantities of ingredients, reaction conditions, etc. used in the specification and claims are to be understood as modified in all instances by the term “about.”
  • The present invention relates to a method for manufacturing niobium wrought products. The method provides a significant reduction as well as better control of the final grain size in niobium wrought products. More particularly, the present invention provides niobium wrought products that contain greater than 5 ppm of the alloying metal, which has a consistently fine, uniform, and fully recrystallized grain structure.
  • As used herein, the term “wrought products” refers generally to metals that have been exposed to thermo-mechanical processing steps to acquire a specific shape and/or other properties. The thermal steps can include, but are not limited to annealing, baking, smelting and/or melting. The mechanical steps can include, but are not limited to working, forging, rolling, upset forging, upset-and-forge-back techniques, hammer forging, drawback forging, flat forging, round forging, and radial forging.
  • Wrought products, as provided in the present invention include, but are not limited to generally planar metal forms such as foils (less than about 10 mil in thickness), sheets (from about 10 to about 125 mil in thickness), and plates (greater than about 125 mil in thickness. Other wrought product forms can include tubes, where a length of metal is hollow in the center (and can have any cross-sectional internal and external shape, but often those shapes will be circular, oval, square, rectangular, triangular, hexagonal, or octagonal); and rods, which are lengths of metal that are solid throughout and can have any cross-sectional internal and external shape, but often those shapes will be circular, oval, square, rectangular, triangular, hexagonal, or octagonal.
  • In the invention, vacuum arc remelting is used to alloy niobium with low level metal additions along with traditional thermo-mechanical processing with higher annealing temperatures to produce niobium wrought products with a fine and fully recrystallized grain structure. The inventive process provides high yields, a more consistent product, and lower manufacturing costs.
  • In an embodiment of the present invention, the metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium is present at a level of at least 0.01 ppm, in some cases 0.1 ppm and as high as 60 ppm, in some cases 50 ppm based on the total niobium in the niobium ingot. The amount of metal in the niobium can be any value or can range between any of the values recited above.
  • In the present method, a blend containing niobium powder and a metal powder selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium is formed and pressed to form a pressed blend. As used herein, the term “pressed blend” refers to a solid form where a mixture of materials are compressed to form a stable shape, which is capable of being attached to another body, such that when the other body melts, the pressed blend melts and commingles with the elements of the other body.
  • The pressed blends are attached to electrodes that contain niobium using a suitable method and both are melted under vacuum arc remelting (VAR) conditions and subsequently cooled. In other words, the niobium acts as an electrode, and is melted by striking an arc between a charged electrode and the niobium, under vacuum. The arc power can be from 25 to 50V and from 7,000 to 10,000 amps.
  • Typically, a pressed blend of niobium and the metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium is used with a niobium electrode.
  • The melted electrode and pressed blend is cooled to form an alloy ingot.
  • Thermo-mechanical processing steps as indicated above are applied to the alloy ingot to form a wrought product as described above.
  • After forging, the alloy ingot can be vacuum annealed at a temperature of at least 950° C. and up to 1150° C. The annealing temperature for the wrought product can be any value or range between the values recited above.
  • The annealing step can take at least 5 minutes and up to 180 minutes. The length of time for annealing can be any value or can range between any values recited above.
  • The annealing step can result in at least 75% recrystallization and in some cases up to at least 95% recrystallization.
  • In an embodiment of the invention, sequential rolling and annealing steps can be carried out on the alloy ingot. Any suitable combination of rolling and annealing steps can be used. In a particular embodiment of the invention, the following steps are used:
      • I) rolling the wrought product to an intermediate thickness;
      • II) annealing the wrought product of 1) at a temperature of from 950 to 1150° C. for a period of from 30 minutes to 180 minutes;
      • III) rolling the wrought product of 11); and
      • IV) annealing the wrought product of II) at a temperature of from 950 to 1150° C. for a period of from 30 minutes to 180 minutes and then cooling the wrought product to room temperature.
  • In an embodiment of the invention, the intermediate thickness 1) can be from 0.5 to 2 cm and the wrought product II) can have a thickness of from 0.005 to 0.24 cm.
  • A particular embodiment of the invention provides a method of making an alloy of niobium by
      • a) melting niobium to form a melt;
      • b) adding 0.1 to 60 ppm of a metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium, based on the niobium in the melt;
      • c) cooling the melt to form an alloy ingot;
      • d) applying thermo-mechanical processing steps to the alloy ingot to form a wrought product.
  • The thermo-mechanical processing steps in d) can include i) forging the alloy ingot to form a wrought product; and ii) annealing the wrought product at a temperature of from 950 to 1150° C.
  • Particular sequential rolling and annealing steps can be used in this particular embodiment as described above. The annealing steps can result in at least 75% recrystallization and in some cases up to at least 95% recrystallization.
  • In an alternative embodiment, scrap niobium is consolidated via VAR, ISM, or other cold hearth melting techniques and the metal (selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium) addition made directly to the melt or via the VAR process described above.
  • In the present invention, the cooled, annealed plate and sheet has a fine and uniform ASTM grain size up to 10, and can be as coarse as 5. In an embodiment of the invention, the ASTM grain size is in the range of 8 to 10.
  • The present invention also provides for wrought product made according to the above described processes, where the wrought products are selected from a foil, a sheet, a plate, a tube, and a rod.
  • The present invention also provides for deep drawn cups or sputtering targets obtained using, made from, or including the above-described wrought products.
  • Not wishing to be bound to a single theory, it is believed that the metal (selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium) combines with niobium to form alloy particles in the niobium or possibly with oxygen to produce sub-micron size oxides of the respective metal added. Rolling (cold working) to sheet produces a uniform dispersion of these particles that on subsequent annealing act initially as grain nucleation sites and, with continued annealing, as grain boundary pinning points.
  • Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims.

Claims (26)

1. A method of making an alloy of niobium comprising:
A) forming a blend comprising niobium powder and a powder of a metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium and pressing the blend to form pressed blend;
B) attaching the pressed blend to an electrode comprising niobium;
C) melting the electrode and pressed blend under vacuum arc remelting conditions, such that the blend mixes with the melted electrode;
D) cooling the melted electrode to form an alloy ingot; and
E) applying thermo-mechanical processing steps to the alloy ingot to form a wrought product.
2. The method according to claim 1, wherein the wrought product in E) has a fine and uniform ASTM grain size of from 5 to 10.
3. The method according to claim 1, wherein the metal is present in A) at from 0.1 to 100 ppm based on total niobium in the wrought product.
4. The method according to claim 1, wherein the thermo-mechanical processing steps in E) comprise:
i) forging the alloy ingot to form a wrought product; and
ii) annealing the wrought product at a temperature of from 950 to 1150° C.
5. The method according to claim 4, wherein the wrought product is selected from the group consisting of foils, sheets, plates, tubes, and rods.
6. The method according to claim 4, wherein the annealing in i) results in at least 75% recrystallization.
7. The method according to claim 1, wherein the thermo-mechanical processing steps in E) comprise:
I) rolling the wrought product to an intermediate thickness;
II) annealing the wrought product of 1) at a temperature of from 950 to 1150° C. for a period of from 30 minutes to 180 minutes;
III) rolling the wrought product of 11); and
IV) annealing the wrought product of II) at a temperature of from 950 to 1150° C. for a period of from 30 minutes to 180 minutes and then cooling the wrought product to room temperature.
8. The method according to claim 6, wherein the wrought product is selected from the group consisting of foils, sheets, plates, tubes, and rods.
9. The method according to claim 7, wherein the annealing in 11) and IV) result in at least 75% recrystallization.
10. A niobium containing wrought product obtained according to the method of claim 1.
11. The wrought product according to claim 10, wherein the wrought product is selected from the group consisting of a foil, a sheet, a plate, a tube, and a rod.
12. Deep drawn cups prepared from the wrought product according to claim 10.
13. Sputtering targets prepared from the wrought product according to claim 10.
14. A method of making an alloy of niobium comprising:
a) melting niobium to form a melt;
b) adding 0.1 to 60 ppm of a metal selected from the group consisting of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum and cerium, based on the niobium in the melt;
c) cooling the melt to form an alloy ingot;
d) applying thermo-mechanical processing steps to the alloy ingot to form a wrought product.
15. The method according to claim 14, wherein the wrought product has a fine and uniform ASTM grain size of from 5 to 10.
16. The method according to claim 14, wherein the metal is present in b) at from 0.1 to 100 ppm based on total niobium.
17. The method according to claim 14, wherein the thermo-mechanical processing steps in d) comprise:
i) forging the alloy ingot to form a wrought product; and
ii) annealing the wrought product at a temperature of from 950 to 1150° C.
18. The method according to claim 17, wherein the wrought product is selected from the group consisting of foils, sheets, plates, tubes, and rods.
19. The method according to claim 17, wherein the annealing in i) results in at least 75% recrystallization.
20. The method according to claim 14, wherein the thermo-mechanical processing steps in d) comprise:
I) rolling the wrought product to an intermediate thickness;
II) annealing the wrought product of 1) at a temperature of from 950 to 1150° C. for a period of from 30 minutes to 180 minutes;
III) rolling the wrought product of 11); and
IV) annealing the wrought product of II) at a temperature of from 950 to 1150° C. for a period of from 30 minutes to 180 minutes and then cooling the wrought product to room temperature.
21. The method according to claim 20, wherein the wrought product is selected from the group consisting of foils, sheets, plates, tubes, and rods.
22. The method according to claim 21, wherein the annealing in 11) and IV) result in at least 75% recrystallization.
23. A niobium containing wrought product obtained according to the method of claim 14.
24. The wrought product according to claim 23, wherein the wrought product is selected from the group consisting of a foil, a sheet, a plate, a tube, and a rod.
25. Deep drawn cups prepared from the wrought product according to claim 23.
26. Sputtering targets prepared from the wrought product according to claim 24.
US11/216,498 2005-08-31 2005-08-31 Fine grain niobium sheet via ingot metallurgy Abandoned US20070044873A1 (en)

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US11/216,498 US20070044873A1 (en) 2005-08-31 2005-08-31 Fine grain niobium sheet via ingot metallurgy
CA002619813A CA2619813A1 (en) 2005-08-31 2006-08-21 Production of fine grain micro-alloyed niobium sheet via ingot metallurgy
JP2008529106A JP2009506219A (en) 2005-08-31 2006-08-21 Production of fine particle microalloyniobium sheet by ingot metallurgy.
MX2008002746A MX2008002746A (en) 2005-08-31 2006-08-21 Production of fine grain micro-alloyed niobium sheet via ingot metallurgy.
AT06813595T ATE541063T1 (en) 2005-08-31 2006-08-21 PRODUCTION OF A FINE-GRAIN MICRO-ALLOYED NIOBIA SHEET USING BLOCK METALLURGY
EP11177836.1A EP2388346B1 (en) 2005-08-31 2006-08-21 Production of fine grain niobium products by micro-alloying and ingot metallurgy
PCT/US2006/032578 WO2007027466A2 (en) 2005-08-31 2006-08-21 Production of fine grain micro-alloyed niobium sheet via ingot metallurgy
EP11177827.0A EP2388345B1 (en) 2005-08-31 2006-08-21 Fine grain niobium wrought products obtained by VAR ingot metallurgy
RU2008111870/02A RU2008111870A (en) 2005-08-31 2006-08-21 MANUFACTURE OF SHEETS OF FINE-GRAIN MICRO-ALLOYED NIOBIUM BY METALLURGY INGOTS
CN200680030944A CN101680055A (en) 2005-08-31 2006-08-21 Production of fine grain micro-alloyed niobium sheet via ingot metallurgy
EP06813595A EP1924718B1 (en) 2005-08-31 2006-08-21 Production of fine grain micro-alloyed niobium sheet via ingot metallurgy
TW095131878A TW200722205A (en) 2005-08-31 2006-08-30 Fine grain niobium sheet via ingot metallurgy background of the invention
NO20081363A NO20081363L (en) 2005-08-31 2008-03-14 Preparation of fine-grained micro-mixed niobium sheets via stop block metallurgy
US13/463,024 US9255309B2 (en) 2005-08-31 2012-05-03 Fine grain niobium sheet via ingot metallurgy

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EP2388346B1 (en) 2019-05-22
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RU2008111870A (en) 2009-10-10
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TW200722205A (en) 2007-06-16
US20120241054A1 (en) 2012-09-27
JP2009506219A (en) 2009-02-12
CA2619813A1 (en) 2007-03-08

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