US3830603A - Apparatus for production of metal powder from wire stock - Google Patents

Apparatus for production of metal powder from wire stock Download PDF

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Publication number
US3830603A
US3830603A US00344040A US34404073A US3830603A US 3830603 A US3830603 A US 3830603A US 00344040 A US00344040 A US 00344040A US 34404073 A US34404073 A US 34404073A US 3830603 A US3830603 A US 3830603A
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US
United States
Prior art keywords
disc
wire
rotation
metal
particles
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 - Lifetime
Application number
US00344040A
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English (en)
Inventor
J Blucher
D Dalrymple
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Industrial Materials Technology Inc
National Forge Co
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Industrial Materials Technology Inc
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Filing date
Publication date
Application filed by Industrial Materials Technology Inc filed Critical Industrial Materials Technology Inc
Priority to US00344040A priority Critical patent/US3830603A/en
Priority to JP49029881A priority patent/JPS5062852A/ja
Priority to GB1194174A priority patent/GB1430500A/en
Priority to FR7409539A priority patent/FR2222159B1/fr
Priority to DE19742413973 priority patent/DE2413973C3/de
Priority to US05/463,656 priority patent/US3931375A/en
Publication of US3830603A publication Critical patent/US3830603A/en
Application granted granted Critical
Assigned to SECURITY PACIFIC BUSINESS CREDIT INC., A CORP. OF DE. reassignment SECURITY PACIFIC BUSINESS CREDIT INC., A CORP. OF DE. SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: INDUSTRIAL MATERIALS TECHNOLOGY, INC., A CORP. OF DE., NATIONAL FORGE COMPANY, A CORP. OF DE.
Anticipated expiration legal-status Critical
Assigned to NATIONAL FORGE COMPANY reassignment NATIONAL FORGE COMPANY ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: INDUSTRIAL MATERIALS TECHNOLOGY, INC. 155 RIVER STREET ANDOVER, MASS. 01810
Assigned to CIT GROUP/CREDIT FINANCE, INC., THE reassignment CIT GROUP/CREDIT FINANCE, INC., THE SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: NATIONAL FORGE COMPANY
Assigned to NATIONAL FORGE COMPANY reassignment NATIONAL FORGE COMPANY RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: CIT GROUP/CREDIT FINANCE, INC., THE
Assigned to NATIONAL FORGE COMPANY, INDUSTRIAL MATERIALS TECHNOLOGY, INC. reassignment NATIONAL FORGE COMPANY FULL RELEASE Assignors: SECURITY PACIFIC BUSINESS CREDIT, INC.
Assigned to NATIONAL FORGE COMPANY, INDUSTRIAL MATERIALS TECHNOLOGY, INC. reassignment NATIONAL FORGE COMPANY FULL RELEASE Assignors: SECURITY PACIFIC BUSINESS CREDIT, INC.
Assigned to NATIONAL FORGE COMPANY reassignment NATIONAL FORGE COMPANY MERGER (SEE DOCUMENT FOR DETAILS). Assignors: NFIP, INC.
Expired - Lifetime legal-status Critical Current

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    • 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
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/14—Making metallic powder or suspensions thereof using physical processes using electric discharge
    • 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
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
    • B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
    • B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
    • B22F2009/084—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid combination of methods
    • 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
    • B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy

Definitions

  • the rotation of the disc breaks the electrical contact and forms an are which causes additional melting of the wire.
  • Contact between the wire and disc takes place within a second electromagnetic field. Continuously advancing the end of the wire causes the intermittent making and breaking of electrical contact.
  • the interaction of the two magnetic fields causes the molten particles to be removed from the area of contact.
  • Means are provided for cooiing and collecting the metal particles and for preventing the accumulation of solidified metal particles on the electromagnet or the rotating disc. Vacuum conditions may be used, thus producing a powder of high purity.
  • This invention relates to an improved process and apparatus for the production of metal powder from solid material such as metal wire or rod.
  • Fine metal powder is being used increasingly in the manufacture of parts by powder metallurgical techniques.
  • Many methods of making metal powders have been proposed. These include the atomization of molten metal by gas jets (Helin et al. U.S. Pat. No. 3,428,718) or by high pressure water (Huseby U.S. Pat. No. 3,325,277); spraying molten metal into a vacuum to form discrete particles (Wentzell U.S. Pat. No. 3,510,546); the vaporization of metal in a vacuum followed by condensation (Allen et al. U.S. Pat. No.
  • the object of the present invention is to produce fine metal powder from a wire or rod by forming particles of molten metal in an electric arc and removing the formed particles by the interaction of two magnetic fields operating at right angles to one another.
  • the operation may take place in a vacuum chamber thus eliminating the chance of contamination by, for example, the formation of oxides.
  • a wire or rod with the chemical analysis desired in the final powder product is brought into contact with a disc which is rotating in a strong magnetic field produced by an electromagnet.
  • the wire and disc are attached to a source of direct current and sufficient voltage is impressed across them to cause electrical current to flow through the circuit to produce the required heat at the point of contact between the wire and disc to rapidly melt the metal.
  • the flow of current through the wire produces a magnetic field around the wire. This field interacts with the magnetic field produced by the electromagnet to force the metal particles away from the point of contact between the wire and the rotating disc.
  • the cooled and solidified particles are thereafter collected.
  • Means are provided for cooling theapparatus and for avoiding the tendency of the powder particles to agglomerate between the pole pieces of the electromagnet.
  • means are provided to remove any build up of powder particles which may form on the rotating disc.
  • FIG. 2 is a vertical section taken generally along the line 2'-2 of FIG. 1, with water cooling pipes and electrical connections omitted.
  • FIG. 3 is a horizontal section taken generally along the line 3--3 of FIG. 1.
  • FIG. 4 is a perspective view of the electromagnet and water-cooled copper terminals utilized in the invention.
  • a deeply grooved disc 10 is placed in the gap 12 of electromagnet 14 energized by coil 16.
  • the disc is mounted for rotation on watercooled shaft 18 driven through pulley 19 by motor 20.
  • Each end of shaft 18 is provided with vacuum-tight rotary joints (not shown).
  • Electrical current is supplied to disc 10 by means of a slip ring 22 mounted on shaft 18 in contact with carbon brush 24 which in turn is connected by conductor 25 to the negative terminal of a source of direct current (not shown).
  • a wire reel 26 is mounted for rotation in frame 28.
  • Metal wire 30 having a chemical composition of that desired in the final powder product is drawn from the reel by a conventional wire feeder 32 powered by a variable speed motor 34 controlled by electronic controller 36 adjustable through knob 37.
  • Wire 30 is fed downwardly through guide tube 38 water cooled by housing 40. Electrical current is supplied to wire 30 through guide tube 38 which is connected by conductor 41 to the-positive terminal of the source of direct current that supplies currentto disc 10.
  • the flow of electrical current through the wire 30 produces a magnetic field around the wire in accordance with well known principles of electricity and magnetism.
  • the direction of feed of the wire is substantially perpendicular to the axis of rotation of disc 10 and in addition is substantially perpendicular to the lines of magnetic force (not shown) in the gap 12 between pole pieces 44 and 46 of electromagnet 14.
  • the metal particles 47 formed are driven out of the area of contact between the metal wire and the disc due to the interaction between the magnetic field produced by the passage of an electrical current in the wire and the second magnetic field transverse thereto produced by the electromagnet.
  • a second device which acts to keep the gap 12 free from solidified metal particles which may tend to bridge between pole pieces 44 and 46 is a deeply grooved copper disc 54 mounted for rotation within gap 12 of electromagnet 14 and in close proximity to disc 10.
  • the axis of rotation of disc 54 is parallel to that of disc 10.
  • the direction of rotation of disc 54 is opposite that of disc 10, as shown by directional arrows 55 and 57, so that the adjacent peripheral surfaces of the two discs move generally in the same direction, i.e., from right to left as shown in FIG. 2.
  • Disc 54 is rotated through pulley 56 driven by motor 20.
  • a crossover belt arrangement is utilized to drive disc 54 in the opposite direction to that given to disc 10.
  • Disc 54 is mounted on water-cooled shaft 58.
  • Rotary joints 60 and 62 serve as support bearings as well as means for getting cooling water through hollow bored shaft 58.
  • Disc 54 may be made of copper because of its excellent heat conduction characteristics and is thus kept cool by the water flowing through shaft 58.
  • a wiper blade 64 is installed in close proximity to the inner faces of the groove in copper disc 54 to prevent metal powder particles from adhering thereto.
  • disc 10 is made of graphite but it could also be made of metal of the same chemical analysis as the final powder product.
  • the entire apparatus may be mounted within a vacuum chamber 66 connected to vacuum outlet 67.
  • the chamber may be a conventional steel tank with hinged and sealable doors 72 at each end.
  • Sight viewing ports 74 may be installed in several locations along with vacuum-tight electrical and cooling water connections 76.
  • particles of metal are produced from metal wire 30 by continuously feeding the wire toward rotating disc 10, the axis of rotation of which is substantially perpendicular to the direction of feed of the wire.
  • the advancing end 42 of the wire is brought into contact with the rotating disc 10 within the field of an electromagnet 14 having lines of force with components substantially perpendicular to the direction of feed of the wire and substantially parallel to the axis of rotation of disc 10.
  • a direct electrical potential is applied between the wire and the disc causing direct current to flow through the wire and the disc, completing an electrical circuit and causing a magnetic field to form around the advancing wire.
  • This magnetic field has lines of force substantially perpendicular to the lines of force of the electromagnetic field of electromagnet 14.
  • the current is of a magnitude sufficient to cause the end of the wire in contact with the disc to melt. Rotation of the disc together with the melting action cause the breaking of electrical contact and the formation of an are between the end of the wire and the disc.
  • Discrete particles 47 of the metal are driven out of the area of contact between the wire and the disc by the interaction between the magnetic field produced by the passage of current in the continuously advancing wire and the magnetic field transverse thereto produced by the electromagnet. 1
  • the entire operation may be carried out in a vacuum thus avoiding contamination of the formed metal particles.
  • the material to be powdered is in the form of metal wire.
  • a wire rod of substantially increased diameter could be continuously fed, with appropriate changes in the feed mechanism, against the revolving disc 10, which could also be modified to accept a rod of increased diameter. It should therefore be understood that when the term wire is used herein it encompasses not only metal in flexible wire form but also metal in the form of a solid rod up to several inches in diameter.
  • Apparatus for producing powder particles from metal wire comprising:
  • said electrical current being of a magnitude sufficient to melt the advancing end of said wire when in contact with said disc whereby the melting of said wire and the rotation of said disc combine to cause an intermittent breaking of said electrical circuit and the formation of an electrical arc between said wire and said disc within said first magnetic field and whereby discrete particles of metal are formed from said wire and are directed out of the zone of contact of said wire and said disc by interaction of said first and second magnetic fields.
  • Apparatus for producing powder particles from metal wire as defined in claim 1 wherein said apparatus is mounted within a vacuum chamber.
  • Apparatus for producing powder particles from metal wire as defined in claim 1 and means for removing particles magnetically attracted to said pole members said means comprising a first and second copper terminal fixed to said pole members, respectively, and means for supplying an alternating electrical current to said terminals during operation of said apparatus.

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  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
US00344040A 1973-03-22 1973-03-22 Apparatus for production of metal powder from wire stock Expired - Lifetime US3830603A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US00344040A US3830603A (en) 1973-03-22 1973-03-22 Apparatus for production of metal powder from wire stock
JP49029881A JPS5062852A (fr) 1973-03-22 1974-03-15
GB1194174A GB1430500A (en) 1973-03-22 1974-03-18 Production of metal powder
FR7409539A FR2222159B1 (fr) 1973-03-22 1974-03-20
DE19742413973 DE2413973C3 (de) 1973-03-22 1974-03-22 Verfahren zur Herstellung von Metallteilchen in Pulverform durch Abschmelzen eines Drahtes
US05/463,656 US3931375A (en) 1973-03-22 1974-04-24 Production of metal powder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00344040A US3830603A (en) 1973-03-22 1973-03-22 Apparatus for production of metal powder from wire stock

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US05/463,656 Division US3931375A (en) 1973-03-22 1974-04-24 Production of metal powder

Publications (1)

Publication Number Publication Date
US3830603A true US3830603A (en) 1974-08-20

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Application Number Title Priority Date Filing Date
US00344040A Expired - Lifetime US3830603A (en) 1973-03-22 1973-03-22 Apparatus for production of metal powder from wire stock

Country Status (4)

Country Link
US (1) US3830603A (fr)
JP (1) JPS5062852A (fr)
FR (1) FR2222159B1 (fr)
GB (1) GB1430500A (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4264641A (en) * 1977-03-17 1981-04-28 Phrasor Technology Inc. Electrohydrodynamic spraying to produce ultrafine particles
WO1990000936A1 (fr) * 1988-07-19 1990-02-08 United States Department Of Energy Procede et appareil d'atomisation et de pulverisation de metaux fondus
US5062936A (en) * 1989-07-12 1991-11-05 Thermo Electron Technologies Corporation Method and apparatus for manufacturing ultrafine particles
US5194128A (en) * 1989-07-12 1993-03-16 Thermo Electron Technologies Corporation Method for manufacturing ultrafine particles
US20130015608A1 (en) * 2007-05-17 2013-01-17 Hamby Kenneth W Pelletization of pyrolyzed rubber products
CN104493189A (zh) * 2015-01-09 2015-04-08 中国久远高新技术装备公司 基于可控磁悬浮熔炼技术的金属粉末制备方法及装置
WO2017184194A1 (fr) 2016-04-20 2017-10-26 Hrl Laboratories, Llc Appareil de fabrication de nanoparticules et suspensions de nanoparticules

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002517172A (ja) * 1991-04-04 2002-06-11 アクトシオネルノエ・オブシェストボ “セルヴェル” 高度に分散された粉末を製造する方法及び該方法を実施するための装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1887577A (en) * 1928-03-22 1932-11-15 Bridger Theo Eustace Method of and apparatus for creating metallic spray
US2795819A (en) * 1954-08-23 1957-06-18 Erwin A Lezberg Apparatus for the preparation of metal powder
US3275787A (en) * 1963-12-30 1966-09-27 Gen Electric Process and apparatus for producing particles by electron melting and ultrasonic agitation
US3313608A (en) * 1964-12-11 1967-04-11 Corning Glass Works Method and apparatus for manufacturing glass beads
US3752610A (en) * 1969-12-18 1973-08-14 S Glazunov Device for producing fine powder of liquid metal

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1887577A (en) * 1928-03-22 1932-11-15 Bridger Theo Eustace Method of and apparatus for creating metallic spray
US2795819A (en) * 1954-08-23 1957-06-18 Erwin A Lezberg Apparatus for the preparation of metal powder
US3275787A (en) * 1963-12-30 1966-09-27 Gen Electric Process and apparatus for producing particles by electron melting and ultrasonic agitation
US3313608A (en) * 1964-12-11 1967-04-11 Corning Glass Works Method and apparatus for manufacturing glass beads
US3752610A (en) * 1969-12-18 1973-08-14 S Glazunov Device for producing fine powder of liquid metal

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4264641A (en) * 1977-03-17 1981-04-28 Phrasor Technology Inc. Electrohydrodynamic spraying to produce ultrafine particles
WO1990000936A1 (fr) * 1988-07-19 1990-02-08 United States Department Of Energy Procede et appareil d'atomisation et de pulverisation de metaux fondus
US4919335A (en) * 1988-07-19 1990-04-24 The United States Of America As Represented By The United States Department Of Energy Method and apparatus for atomization and spraying of molten metals
US5062936A (en) * 1989-07-12 1991-11-05 Thermo Electron Technologies Corporation Method and apparatus for manufacturing ultrafine particles
US5194128A (en) * 1989-07-12 1993-03-16 Thermo Electron Technologies Corporation Method for manufacturing ultrafine particles
US20130015608A1 (en) * 2007-05-17 2013-01-17 Hamby Kenneth W Pelletization of pyrolyzed rubber products
US9139738B2 (en) * 2007-05-17 2015-09-22 Tellus Technology, Inc. Pelletization of pyrolyzed rubber products
US9902859B2 (en) 2007-05-17 2018-02-27 Tellus Technology, Inc. Pelletization of pyrolyzed rubber products
CN104493189A (zh) * 2015-01-09 2015-04-08 中国久远高新技术装备公司 基于可控磁悬浮熔炼技术的金属粉末制备方法及装置
WO2017184194A1 (fr) 2016-04-20 2017-10-26 Hrl Laboratories, Llc Appareil de fabrication de nanoparticules et suspensions de nanoparticules
EP3445709A4 (fr) * 2016-04-20 2019-11-13 HRL Laboratories, LLC Appareil de fabrication de nanoparticules et suspensions de nanoparticules

Also Published As

Publication number Publication date
DE2413973B2 (de) 1977-06-08
FR2222159A1 (fr) 1974-10-18
JPS5062852A (fr) 1975-05-29
FR2222159B1 (fr) 1979-03-16
GB1430500A (en) 1976-03-31
DE2413973A1 (de) 1974-09-26

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