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DE2628207A1 - Soft magnetic moulded bodies mfr. - from mixture of powdered magnetic material and binder contg. a solvent for the binder - Google Patents

Soft magnetic moulded bodies mfr. - from mixture of powdered magnetic material and binder contg. a solvent for the binder

Info

Publication number
DE2628207A1
DE2628207A1 DE19762628207 DE2628207A DE2628207A1 DE 2628207 A1 DE2628207 A1 DE 2628207A1 DE 19762628207 DE19762628207 DE 19762628207 DE 2628207 A DE2628207 A DE 2628207A DE 2628207 A1 DE2628207 A1 DE 2628207A1
Authority
DE
Germany
Prior art keywords
binder
magnetic material
mixture
solvent
pressed
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.)
Withdrawn
Application number
DE19762628207
Other languages
German (de)
Inventor
Heinz Ing Grad Seidel
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.)
Draloric Electronic GmbH
Original Assignee
Draloric Electronic GmbH
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 Draloric Electronic GmbH filed Critical Draloric Electronic GmbH
Priority to DE19762628207 priority Critical patent/DE2628207A1/en
Publication of DE2628207A1 publication Critical patent/DE2628207A1/en
Withdrawn legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12Magnets 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
    • H01F1/14Magnets 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
    • H01F1/20Magnets 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
    • H01F1/22Magnets 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
    • H01F1/24Magnets 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
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01FMAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12Magnets 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
    • H01F1/14Magnets 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
    • H01F1/20Magnets 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
    • H01F1/22Magnets 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
    • H01F1/24Magnets 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
    • H01F1/26Magnets 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 by macromolecular organic substances

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  • Chemical & Material Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Manufacturing Cores, Coils, And Magnets (AREA)
  • Powder Metallurgy (AREA)

Abstract

Soft magnetic moulded bodies are mfd. by (a) dry mixing a powdered magnetic material and a binder; (b) suspending the mixt. in a solvent suitable for the binder and mixing; (c) treating the mixt. pref. at elevated temps. to evaporate the solvent; and (d) forming the resulting agglomerate into a granulate which can then be pressed into the desired shapes. The bodies have improved magnetic props. and low shrinkage during the heat-treatment process. Other metal parts may be easily incorporated.

Description

VERFAHREN ZUR HERSTELLUNG VON AUS MAGNETWERKSTOFF METHOD FOR MANUFACTURING FROM MAGNETIC MATERIAL

UND EINEM BINDEMITTEL GEPRESSTEN WEICHMAGNETISCHEN FORMKÖRPERN Die Erfindung betrifft ein Verfahren zur Herstellung von aus Magnetwerkstoff und einem Bindemittel gepreßten weichmagnetischen Formkörpern, bei dem aus dem pulverförmigen Magnetwerkstoff und dem Bindemittel nach dem Mischen eine granulierbare Masse heFgestellt wird, die zu einem preßfahigen Granulat zerkleinert wird, aus welchem dann die Formkörper durch Pressen hergestellt werden. AND A BINDING AGENT PRESSED SOFT MAGNETIC SHAPED BODIES The invention relates to a method for producing from magnetic material and a Binder pressed soft magnetic moldings, in which from the powdery Magnetic material and the binding agent, after mixing, make a granulatable mass which is comminuted to a pressable granulate, from which the moldings are then made be made by pressing.

Aus der DT-OS 2 115 536 ist ein Verfahren zur Herstellung von Dauermagneten bekannt, bei dem ein pulverförmiger Magnetwerkstoff mit einem pulverförmigen Bindemittel gemischt wird. Diese Mischung wird dann solange und so hoch erwärmt, bis die Teilchen leicht zusammenbacken; Nach dem Abkühlen der Mischung wird der so erhaltende Kuchen zu einem preßfähigen Granulat zerkleinert. Aus diesem Granulat werden dann kalt die Magnetkörper in ihre endgültige Form gepreßt. Durch anschließendes längeres Erwärmen (etwa 0 1 Stunde) bis auf 200 C wird dann das Bindemittel zum Aushärten gebracht.From DT-OS 2 115 536 a method for the production of permanent magnets is known, in which a powdery magnetic material with a powdery binder is mixed. This mixture is then heated up until the particles caking easily; After cooling the mixture, the cake thus obtained becomes to a pressable one Crushed granules. From this granulate the magnetic bodies are then cold-pressed into their final shape. By subsequent prolonged heating (about 0 1 hour) up to 200 C is then the binder for Brought curing.

Aus der DT-OS 2 429 559 ist ein Verfahren der eingangs genannten Art zur Herstellung von Dauermagneten bekannt, bei dem der pulverförmige Magnetwerkstoff mit einem flüssigen Bindemittel unter gleichzeitiger Erwärmung gemischt wird, dieses Gemisch vorzugsweise bei Raumtemperatur solange einer Aushärtung ausgesetzt wird, bis eine granulierbare Masse entsteht, aus der nach dem Granulieren die Magntkörper unter Erwärmung der Masse bis zur endgültigen Aushärtung gepreßt werden. Dabei dauert die Aushärtung des Gemisches ca. 24 Stunden, wonach das so erhaltene Granulat wie ein Duroplast zu Magnetkörpern verpreßt werden kann.From DT-OS 2 429 559 a method of the type mentioned above is known for the production of permanent magnets, in which the powdery magnetic material is mixed with a liquid binder with simultaneous heating, this Mixture is exposed to curing, preferably at room temperature, until a mass which can be granulated is produced, from which the magnetic bodies after granulation are pressed while heating the mass until final hardening. It lasts the hardening of the mixture about 24 hours, after which the granules obtained in this way as a thermoset can be pressed to form magnetic bodies.

Es ist allgemein bekannt, bei weichmagnetischen Formkörpern dem Magnetwerkstoff ein duroplastisches Bindemittel beizugeben. Dabei ist es jedoch erforderlich, das Gemisch bei erhöhter Temperatur zu verarbeiten, bzw. die Formmatrize zu erhitzen.It is generally known, in the case of soft magnetic molded bodies, the magnetic material to add a thermosetting binder. However, this requires the To process the mixture at an elevated temperature or to heat the molding die.

Der Erfindung liegt die Aufgabe zugrunde, ein einfaches Verfahren zur Herstellung von weichmagnetischen Formkörpern der eingangs erwähnten Art zu schaffen, mit dem auch unterschiedlich geformte Weichmagnete auf wirtschaftliche Weise hergestellt werden können. Insbesondere sollen mit dem erfindungsgemäßen Verfahren auch weichmagnetische Formkörper bei kleinsten Abmessungen eine größtmögliche Maßhaltigkeit und mechanische Festigkeit aufweisen.The invention is based on the object of a simple method for the production of soft magnetic moldings of the type mentioned create, with which even differently shaped soft magnets on economical Way can be made. In particular, with the method according to the invention Even soft magnetic moldings with the smallest dimensions have the greatest possible dimensional accuracy and have mechanical strength.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß der pulverförmige Magnetwerkstoff mit einem Bindemittel trocken gemischt, anschließend diese Mischung in einem für das Bindemittel geeigneten Lösungsmittel aufgeschlämmt und nochmals vermischt wird, dieses Gemisch vorzugsweise bei erhöhter Temperatur behandelt wird, bei der das Lösungsmittel verdampft, anschließend das so erhaltene Agglomerat zu Granulat verarbeitet wird, aus dem die weichmagnetischen Formkörper gepreßt werden.This object is achieved in that the powdery Magnetic material dry mixed with a binding agent, then this mixture slurried in a solvent suitable for the binder and again is mixed, this mixture is preferably treated at an elevated temperature, in which the solvent evaporates, then the agglomerate obtained in this way Granulate is processed, from which the soft magnetic moldings are pressed.

Als Magnetwerkstoff finden Eisen bzw. Eisenlegierungen mit einer Hauptkorngröße von 20 bis 150 Mikrometer Verwendung.Iron or iron alloys with a main grain size are used as magnetic materials from 20 to 150 microns use.

Der Hauptkornanteil hängt in der Hauptsache von der Kornform und der Verformbarkeit des verwendeten Materials ab und liegt vorzugsweise im Bereich zwischen 50 und 10 Mikrometer.The main grain content depends mainly on the grain shape and the Deformability of the material used and is preferably in the range between 50 and 10 microns.

Der Bindemittelanteil beträgt 0,1 . 3 Gewichtsprozent, vorzugsweise 0,1 5 1,0 Gewichtsprozent; es ist also erfindungsgemäß nur sehr wenig Bindemittel vorhanden, was sich'auf die magnetischen Eigenschaften positiv auswirkt.The proportion of binder is 0.1. 3 percent by weight, preferably 0.1 5 1.0 weight percent; there is therefore very little binder in accordance with the invention present, which has a positive effect on the magnetic properties.

Erfindungsgemäß wird als Bindemittel ein Silikonharzpulver verwendet, welches in einem leichtflüchtigen organischen Lösungsmittel, z.B. Aceton löslich ist. Das Lösungsmittel wird bei einer Temperatur von 30 bis 50°C verdampft, anschließend das erhaltene Agglomerat granuliert und daraus die weichmagnetischen Formkörper gepreßt. Diese werden 0 60 Minuten bei 180 C thermisch nachbehandelt.According to the invention, a silicone resin powder is used as the binder, which is soluble in a volatile organic solvent, e.g. acetone is. The solvent is evaporated at a temperature of 30 to 50 ° C, then the agglomerate obtained is granulated, and from it the soft magnetic shaped bodies pressed. These are thermally aftertreated at 180 ° C. for 0 60 minutes.

t Die mit der Erfindung erzielten Vorteile liegen darin, daß die magnetischen Eigenschaften derartiger weichmagnetischer Formkörper besser sind als bei herkömmlichen. Dies mag mit der relativ hohen Dichte der Formkörper, welche nur ca. 15 % unter der des Reinmetalls liegt, zusammenhängen. t The advantages achieved by the invention are that the magnetic properties of such soft magnetic molded bodies are better than with conventional. This may be due to the relatively high density of the molded body, which is only approx. 15% below that of the pure metal.

Ein weiterer Vorteil liegt darin, daß die Formkörper während der thermischen Nachbehandlung praktisch keinerlei Schwindung erfahren. Außerdem weist das.erfindungsgemäße Verfahren noch den Vorteil auf, daß weitere Metallteile, wie beispielsweise Achsen,ohne Schwierigkeiten mit ein-bzw. umgepreßt werden können. Das Granulat ist rieselfähig und kann auf Automaten verarbeitet werden.Another advantage is that the molded body during the thermal After treatment practically no shrinkage experienced. In addition, the procedure still have the advantage that other metal parts, such as axles, without difficulty with one or. can be re-pressed. The granulate is free-flowing and can open up Machines are processed.

PATENTANSPRÜCHE PATENT CLAIMS

Claims (9)

P A T E N T A N S P R Ü C H E : X Verfahren zur Herstellung von aus Magnetwerkstoff und einem Bindemittel gepreßten weichmagnetischen Formkörpern, bei dem aus dem pulverförmigen Magnetwerkstoff und dem Bindemittel nach dem Mischen eine granulierbare Masse hergestellt wird, die zu einem preßfähigen Granulat zerkleinert wird, aus welchem dann die Formkörper durch Pressen hergestellt werden, dadurch gekennzeichnet, daß der pulverförmige Magnetwerkstoff mit einem Bindemittel trocken gemischt, anschließend diese Mischung in einem für das Bindemittel geeigneten Lösungsmittel aufgeschlämmt und nochmals vermischt wird, dieses Gemisch vorzugsweise bei erhöhter Temperatur behandelt wird, bei der das Lösungsmittel verdampft, anschließend das so entstandene Agglomerat zu Granulat verarbeitet wird, aus dem die weichmagnetischen Formkörper gepreßt werden. P A T E N T A N S P R Ü C H E: X Process for the production of from Magnetic material and a binding agent pressed soft magnetic molded bodies that of the powdered magnetic material and the binder after mixing a granulatable mass is produced, which is comminuted into a pressable granulate is, from which the moldings are then made by pressing, thereby characterized in that the powdery magnetic material is dry with a binder mixed, then this mixture in a solvent suitable for the binder slurried and mixed again, this mixture is preferably at increased Temperature is treated at which the solvent evaporates, then the The resulting agglomerate is processed into granules from which the soft magnetic Moldings are pressed. 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß als Magnetwerkstoff Eisen mit einer Hauptkorngröße zwischen 20 und 150 Mikrometer Verwendung findet. 2. The method according to claim 1, characterized in that the magnetic material Iron with a main grain size between 20 and 150 micrometers is used. 3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Bindemittelanteil 0,1 bis 3,0 Gewichtsprozent, vorzugsweise 0,1 ,* 1,0 Gewichtsprozent beträgt.3. The method according to claim 1, characterized in that the binder content 0.1 to 3.0 percent by weight, preferably 0.1 * 1.0 percent by weight. 4. Verfahren nach einem der Ansprüche 1 bis 3, gekennzeichnet durch die Verwendung eines Silikonharzpulvers als Bindemittel.4. The method according to any one of claims 1 to 3, characterized by the use of a silicone resin powder as a binder. 5. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß der Mischung aus dem pulverförmigen Magnetwerkstoff und dem Bindemittel Aceton im Verhältnis von ca. 100 Teile Mischung zu 25 Teile Aceton zugegeben wird. X 5. The method according to any one of claims 1 to 4, characterized in that that the mixture of the powdered magnetic material and the binding agent acetone is added in a ratio of about 100 parts of the mixture to 25 parts of acetone. X 6. Verfahren nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, daß das Lösungsmittel bei einer Temperatur von 30 bis 500C verdampft wird.6th Method according to one of the preceding claims, characterized in that the Solvent is evaporated at a temperature of 30 to 500C. 7. Verfahren nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß der Formkörper aus dem Granulat bei einer Preßdauer von 2 5 6 Sekunden und einem Druck von 50 k 100 kN/cm gepreßt wird.7. The method according to any one of claims 1 to 6, characterized in that that the molded body from the granules at a pressing time of 2 5 6 seconds and one Pressure of 50 k 100 kN / cm is pressed. 8. Verfahren nach Anspruch 7, dadurch gekennzeichnet, daß der gepreßte Formkörper bei erhöhter Temperatur nachbehandelt wird.8. The method according to claim 7, characterized in that the pressed Shaped body is aftertreated at elevated temperature. 9. Verfahren nach Anspruch 8, dadurch gekennzeichnet, daß der Formkörper bei 180 C in 60 Minuten ausgehärtet wird.9. The method according to claim 8, characterized in that the shaped body is cured at 180 C in 60 minutes.
DE19762628207 1976-06-23 1976-06-23 Soft magnetic moulded bodies mfr. - from mixture of powdered magnetic material and binder contg. a solvent for the binder Withdrawn DE2628207A1 (en)

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Application Number Priority Date Filing Date Title
DE19762628207 DE2628207A1 (en) 1976-06-23 1976-06-23 Soft magnetic moulded bodies mfr. - from mixture of powdered magnetic material and binder contg. a solvent for the binder

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DE19762628207 DE2628207A1 (en) 1976-06-23 1976-06-23 Soft magnetic moulded bodies mfr. - from mixture of powdered magnetic material and binder contg. a solvent for the binder

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DE2628207A1 true DE2628207A1 (en) 1978-01-05

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0092091A2 (en) 1982-04-15 1983-10-26 Allied Corporation Apparatus for the production of magnetic powder
EP0112577A1 (en) * 1982-12-27 1984-07-04 Kabushiki Kaisha Toshiba Magnetic core and method of producing the same
FR2545640A1 (en) * 1983-05-05 1984-11-09 Gen Electric MAGNETIC CORE IN IRON POWDER
EP0145178A1 (en) * 1983-11-16 1985-06-19 Kabushiki Kaisha Toshiba Magnetic powder composition
EP0179557A2 (en) * 1984-10-12 1986-04-30 THORN EMI Patents Limited Improvements in or relating to magnetic powder compacts
EP0205786A1 (en) * 1985-06-26 1986-12-30 Kabushiki Kaisha Toshiba Magnetic core and preparation thereof
DE3901303A1 (en) * 1989-01-18 1990-07-19 Gerd Pruschke Magnetising device for permanent magnets

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0092091A2 (en) 1982-04-15 1983-10-26 Allied Corporation Apparatus for the production of magnetic powder
EP0092091A3 (en) * 1982-04-15 1984-03-07 Allied Corporation Manufacture of powder cores for electromagnetic apparatus
EP0112577A1 (en) * 1982-12-27 1984-07-04 Kabushiki Kaisha Toshiba Magnetic core and method of producing the same
US4543208A (en) * 1982-12-27 1985-09-24 Tokyo Shibaura Denki Kabushiki Kaisha Magnetic core and method of producing the same
FR2545640A1 (en) * 1983-05-05 1984-11-09 Gen Electric MAGNETIC CORE IN IRON POWDER
EP0145178A1 (en) * 1983-11-16 1985-06-19 Kabushiki Kaisha Toshiba Magnetic powder composition
EP0179557A2 (en) * 1984-10-12 1986-04-30 THORN EMI Patents Limited Improvements in or relating to magnetic powder compacts
EP0179557A3 (en) * 1984-10-12 1987-06-24 Emi Limited Improvements in or relating to magnetic powder compacts
EP0205786A1 (en) * 1985-06-26 1986-12-30 Kabushiki Kaisha Toshiba Magnetic core and preparation thereof
DE3901303A1 (en) * 1989-01-18 1990-07-19 Gerd Pruschke Magnetising device for permanent magnets

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