EP0092091B2 - Apparatus for the production of magnetic powder - Google Patents

Apparatus for the production of magnetic powder Download PDF

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Publication number
EP0092091B2
EP0092091B2 EP83103269A EP83103269A EP0092091B2 EP 0092091 B2 EP0092091 B2 EP 0092091B2 EP 83103269 A EP83103269 A EP 83103269A EP 83103269 A EP83103269 A EP 83103269A EP 0092091 B2 EP0092091 B2 EP 0092091B2
Authority
EP
European Patent Office
Prior art keywords
chill surface
width
slot
lip
movement
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.)
Expired
Application number
EP83103269A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0092091A2 (en
EP0092091B1 (en
EP0092091A3 (en
Inventor
Amitava Datta
Davidson M. Nathasingh
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.)
Honeywell International Inc
Original Assignee
Allied Corp
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
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Application filed by Allied Corp filed Critical Allied Corp
Publication of EP0092091A2 publication Critical patent/EP0092091A2/en
Publication of EP0092091A3 publication Critical patent/EP0092091A3/en
Application granted granted Critical
Publication of EP0092091B1 publication Critical patent/EP0092091B1/en
Publication of EP0092091B2 publication Critical patent/EP0092091B2/en
Expired legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
    • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
    • H01F1/147—Alloys characterised by their composition
    • H01F1/153—Amorphous metallic alloys, e.g. glassy metals
    • H01F1/15358—Making agglomerates therefrom, e.g. by pressing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
    • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
    • H01F1/20—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder
    • H01F1/22—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together
    • H01F1/24—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together the particles being insulated

Definitions

  • This invention relates to an apparatus for casting. of metal powder, especially metallic glass powder.
  • Amorphous metal alloys and articles made therefrom are disclosed in US-A-3,856,513. That patent teaches certain novel metal alloy compositions which are obtained in the amorphous state and are superior to previously known crystalline alloys based on the same metals. The compositions taught therein are easily quenched to the amorphous state and possess desirable physical properties. The patent discloses further that amorphous metal powders having a particle size ranging from 10 to 250 um can be made by grinding or air milling the cast ribbon.
  • an apparatus for casting ribbons of a glassy metal alloy comprises a movable chill surface, a reservoir for holding molten metal and a nozzle in communication at its top with the reservoir and having at its bottom an opening in close proximity to the chill surface said chill surface being adapted for longitudinal movement at a velocity of 100 to 2000 meters per minute. Powders cannot be cast directly by this apparatus. If the metal alloys are desired in powder form, for example to be used in a compacting method, the cast ribbons are grinded, ball milled or air milled into powders of desirable size range. To aid the pulverization process ribbon samples are subjected to an embrittlement heat treatment below the crystallization temperature of the alloy.
  • the EP-A-0 008 604 discloses an apparatus for the production of flake particles from a projected stream of molten material comprising: means for containing, heating, and projecting the stream of molten material at super atmospheric pressure; a heat-extracting drum having a serrated peripheral surface with the edges of each serration substantially parallel to the central axis of the drum; means for rotating the drum about its central axis; means for controlling the rate of projection of said molten material; and means for controlling the rate of rotation of the drum relative to the rate of projection of molten material during projection.
  • US-A-4149 884 an apparatus for casting polycrystalline alloys in the form of filaments or ribbons is shown.
  • Said apparatus comprises a rotating disc having semi-circular indentations or notches in its circumferential edge.
  • the objective of the present invention is an apparatus to cast metal powder directly into the final form having a desirable size range, especially to cast metal powder as fine particles.
  • the apparatus for casting of metal powder comprising a movable chill surface (12) having a plurality of regularly spaced peaks (22) and valleys (24), a reservoir (14) for holding molten metal (16) and a nozzle (18) in communication at its top with the reservoir (14) and having at its bottom an opening (20) in close proximity to the chill surface (12), said chill surface (12) being adapted for longitudinal movement at a velocity of 100 to 2000 m/min, and the distance from the top of a peak to the bottom of a valley ranging from 0.005 cm to 0.05 cm is characterized in that said valleys are bounded on all sides by said peaks to delimit a plurality of casting cavities, that the distance between adjacent peaks ranges from 0.01 cm to 0.1 cm, and that the bottom of the nozzle is maintained at a distance between 0.02 and 1 mm from the chill surface.
  • the size of the powder particles thereby produced will vary, depending on the depth of the serrations and the distance therebetween.
  • the apparatus according to the invention typically yields powder particles having a size ranging - from 0.01 to 0.1 cm.
  • the nozzle has a slot arranged generally perpendicular to the direction of movement of said chill surface (12), the slot being defined by a pair of generally parallel lips, a first lip and a second lip numbered in the direction of movement of the chill surface, wherein said slot has a width of from 0.2 to 1 mm, measured in direction of movement of the chill surface, wherein the first lip has a width at least equal to the width of said slot, and said second lip has a width of from 1.5 to 3 times the width of said slot, and wherein the gap between the lips and the chill surface is from 0.1 to 1 times the width of the slot.
  • especially molded magnetic metal alloy articles are produced by a method comprising the step of compacting ferromagnetic glass powder with static pressure at a pressing temperature in the vicinity of the glass transition temperature and below the crystallization temperatures of said alloy, and at a pressure of 69 MPa to 690 MPa.
  • a consolidated, glassy metal alloy body is thereby formed, which is especially adapted to be post fabrication annealed at a temperature ranging from 380 to 450°C for a time period of 1 to 4 hours in the presence of a magnetic field of 0 to 800 A/m.
  • the annealed article has improved impedance permeability and is particularly suited for use in signal and high frequency power transformers and the like.
  • the apparatus 10 has a movable chill surface 12, a reservoir 14 for holding molten metal 16 and a nozzle 18 in communication at its top with reservoir 14 and having at its bottom an opening 20 in close proximity to the chill surface 12.
  • the chill surface 12 has a plurality of regularly spaced peaks 22 and valleys 24. Adjacent peaks are separated by a distance, d, of 0.01 cm to 0.1 cm. The distance, y (not shown), from the top of a peak to the bottom of a valley is 0.005 cm to 0.05 cm.
  • Powder is produced directly by deposition of molten alloy on the serrated substrate (chill surface 12) which is a rotatable chill roll, an endless belt (not shown) or the like, adapted for longitudinal movement at a velocity of 100 to 2000 meters per minute.
  • the size of the powder particles thereby produced varies directly with the magnitude of distances d and y.
  • the nozzle means has a slot arranged generally perpendicular to the direction of movement of the chill surface.
  • the slot is defined by a pair of parallel lips, a first lip and a second lip numbered in the direction of movement of the chill surface.
  • the slot of nozzle 18 has a width of from 0.2 to 1 millimeter, measured in the direction of movement of the chill surface.
  • the first flip has a width at least equal to the width of the slot, and the second lip has a width of from 1.5 to 3 times the width of the slot.
  • the gap between the lips and the chill surface is from 0.1 to 1 times the width of the slot.
  • Powder adapted for consolidation can comprise fine powder (having particle size under 105 micrometers), coarse powder (having particle size between 105 micrometers and 300 micrometers) and flake (having particle size greater than 300 micrometers). Consolidation can be obtained by pressing glassy metal alloy powder near its glass transition and below the crystallization temperature.
  • a particle diameter of less than 105 micrometers is used.
  • larger particle diameters of 300 micrometers or more are employed.
  • powders can be put in evacuated cans and then be formed to strips or isostatically pressed to discs, rings or any other desirable shape such as transformer and inductor cores, motor stators and rotor parts, and the like. Furthermore, powders can be warm pressed below the crystallization temperature and in the region of glass transition temperature into any desirable shapes of the transformer/inductor cores or motor rotor/stator segments. Consolidation is believed to result from mechanical interlocking and short-range diffusion bonding between the powder or flake particles occurring in the vicinity of the glass transition temperature. At temperatures too far below the glass transition temperature (Tg) the particles are relatively hard and are not readily deformed by shear and compressive forces exerted thereon during consolidation. Temperatures too far above Tg enhance the risk of incipient crystallization of the amorphous particles during consolidation. Generally, it has been found that interpartical bonding is best achieved during consolidation at pressing temperatures within 50°C of Tg.
  • the powders can also be mixed with a suitable organic binder, for instance, paraffin, polysulfone, polyimide, phenolic formaldehyde resins, and then cold pressed to suitable forms.
  • a suitable organic binder for instance, paraffin, polysulfone, polyimide, phenolic formaldehyde resins
  • the amount of binder can be up to 30 weight percent and is preferably less than 10 weight percent and more preferably between 0.5 and 3 weight percent for high permeability cores.
  • Such formed alloy can have a density of at least 60 percent of the theoretical maximum.
  • the pressed object can be cured at a relatively low temperature below the curing temperature of the binder to give more strength and then ground to final dimensions.
  • the preferred product of this process comprises shapes suitable as magnetic components.
  • the curing process can be performed with simultaneous application of a magnetic field.
  • a metallic glass is an alloy product of fusion which has been cooled to a rigid condition without crystallization.
  • Such metallic glasses generally have at least some of the following properties: high hardness and resistance to scratching, great smoothness of a glassy surface, dimensional and shape stability, mechanical stiffness, strength, ductility, high electrical resistance compared with related metals and alloys thereof, and a diffuse. X-ray diffraction pattern.
  • alloy is used herein in the conventional sense as denoting a solid mixture of two or more metals (Condensed Chemical Dictionary, Ninth Edition, Van Norstrand Reinhold Co., New York, 1977). These alloys additionally contain admixed at least one non-metallic element.
  • glassy metal alloy "metallic glass”, “amorphous metal alloy” and “vitreous metal alloy” are all considered equivalent as employed herein.
  • alloys suitable for the use in the apparatus of the present invention include the composition Preferred ferromagnetic alloys according to the present invention are based on one member of the group consisting of iron, cobalt and nickel.
  • the iron based alloys have the general composition
  • the cobalt based alloys have the general composition
  • the nickel based alloys have the general composition
  • An especially preferred alloy has the composition 79 atomic percent iron, 16 atomic percent boron and 5 atomic percent silicon.
  • Amorphous metallic powders can be compacted to fabricate parts suitable for a variety of applications such as electromagnetic cores, pole pieces and the tike.
  • the glassy metal compacts have either high or low permeability.
  • the resulting cores can be used as transformer cores, motor stators or rotors and in other alternating current applications.
  • Amorphous alloys that are preferred for such applications include Fe7,B l3 Si 4 , Fe 79 B 16 Si s and Fe 8l B l3 Si 3 . S C 2 .

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Chemical & Material Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Soft Magnetic Materials (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
EP83103269A 1982-04-15 1983-04-02 Apparatus for the production of magnetic powder Expired EP0092091B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US36861282A 1982-04-15 1982-04-15
US368612 1989-06-20

Publications (4)

Publication Number Publication Date
EP0092091A2 EP0092091A2 (en) 1983-10-26
EP0092091A3 EP0092091A3 (en) 1984-03-07
EP0092091B1 EP0092091B1 (en) 1986-06-18
EP0092091B2 true EP0092091B2 (en) 1991-01-30

Family

ID=23451974

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83103269A Expired EP0092091B2 (en) 1982-04-15 1983-04-02 Apparatus for the production of magnetic powder

Country Status (4)

Country Link
EP (1) EP0092091B2 (cg-RX-API-DMAC7.html)
JP (2) JPS5916306A (cg-RX-API-DMAC7.html)
CA (1) CA1232158A (cg-RX-API-DMAC7.html)
DE (1) DE3364158D1 (cg-RX-API-DMAC7.html)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4594104A (en) * 1985-04-26 1986-06-10 Allied Corporation Consolidated articles produced from heat treated amorphous bulk parts
JPH0733521B2 (ja) * 1988-07-01 1995-04-12 セイコー電子部品株式会社 異方性ボンド磁石用合金粉末の製造方法
CA2040741C (en) * 1990-04-24 2000-02-08 Kiyonori Suzuki Fe based soft magnetic alloy, magnetic materials containing same, and magnetic apparatus using the magnetic materials
IT1242582B (it) * 1990-10-05 1994-05-16 Intermac Srl Procedimento per la lavorazione in automatico a filo lucido del bordo di lastre di vetro di forma qualsiasi e macchina per la esecuzione di tale procedimento.
JPH11158502A (ja) * 1997-11-26 1999-06-15 Masaaki Yagi 複合粉末および複合粉末の成形方法
US6930581B2 (en) 2002-02-08 2005-08-16 Metglas, Inc. Current transformer having an amorphous fe-based core
JP4299152B2 (ja) 2004-01-08 2009-07-22 日本碍子株式会社 電磁波シールドケースおよびその製造方法
JP2008141012A (ja) * 2006-12-01 2008-06-19 Hitachi Powdered Metals Co Ltd リアクトル
JP2018152449A (ja) * 2017-03-13 2018-09-27 株式会社東芝 複数の扁平磁性金属粒子、圧粉材料及び回転電機

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2096092A5 (cg-RX-API-DMAC7.html) * 1970-06-08 1972-02-11 Fuji Photo Film Co Ltd
US3856513A (en) * 1972-12-26 1974-12-24 Allied Chem Novel amorphous metals and amorphous metal articles
DE2628207A1 (de) * 1976-06-23 1978-01-05 Draloric Electronic Verfahren zur herstellung von aus magnetwerkstoff und einem bindemittel gepressten weichmagnetischen formkoerpern
US4116728B1 (en) * 1976-09-02 1994-05-03 Gen Electric Treatment of amorphous magnetic alloys to produce a wide range of magnetic properties
US4142571A (en) * 1976-10-22 1979-03-06 Allied Chemical Corporation Continuous casting method for metallic strips
AU503857B2 (en) * 1976-10-22 1979-09-20 Allied Chemical Corp. Continuous casting of metal strip
US4215084A (en) * 1978-05-03 1980-07-29 The Battelle Development Corporation Method and apparatus for producing flake particles
JPS55152155A (en) * 1979-05-16 1980-11-27 Sumitomo Special Metals Co Ltd Fine crystalline strip material for high permeability magnetic material, preparation and product thereof
US4321090A (en) * 1980-03-06 1982-03-23 Allied Corporation Magnetic amorphous metal alloys
JPS57187357A (en) * 1981-05-15 1982-11-18 Aisin Seiki Co Ltd Soft magnetic resin composed of amorphous alloy
JPS58163555A (ja) * 1982-03-24 1983-09-28 Nippon Yakin Kogyo Co Ltd 箔片を溶融材料から直接に製造する装置
JPS58163557A (ja) * 1982-03-25 1983-09-28 Nippon Yakin Kogyo Co Ltd 箔片製造装置
JPS58163556A (ja) * 1982-03-25 1983-09-28 Nippon Yakin Kogyo Co Ltd 箔片製造装置
JPS5939224B2 (ja) * 1982-04-08 1984-09-21 日本冶金工業株式会社 箔片製造装置

Also Published As

Publication number Publication date
JPS5916306A (ja) 1984-01-27
CA1256667C (cg-RX-API-DMAC7.html) 1989-07-04
EP0092091A2 (en) 1983-10-26
JPH0277505A (ja) 1990-03-16
CA1232158A (en) 1988-02-02
DE3364158D1 (en) 1986-07-24
JPH0534814B2 (cg-RX-API-DMAC7.html) 1993-05-25
EP0092091B1 (en) 1986-06-18
EP0092091A3 (en) 1984-03-07

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