EP1032940B1 - Method for producing a magnetic alloy powder - Google Patents
Method for producing a magnetic alloy powder Download PDFInfo
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- EP1032940B1 EP1032940B1 EP98956933A EP98956933A EP1032940B1 EP 1032940 B1 EP1032940 B1 EP 1032940B1 EP 98956933 A EP98956933 A EP 98956933A EP 98956933 A EP98956933 A EP 98956933A EP 1032940 B1 EP1032940 B1 EP 1032940B1
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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
- H01F1/032—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 hard-magnetic materials
- H01F1/04—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 hard-magnetic materials metals or alloys
- H01F1/047—Alloys characterised by their composition
- H01F1/053—Alloys characterised by their composition containing rare earth metals
- H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
- H01F1/0553—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 obtained by reduction or by hydrogen decrepitation or embrittlement
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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
- B22F9/023—Hydrogen absorption
-
- 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
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
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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
- B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy
Definitions
- the invention relates to the field of metallurgical Process engineering and relates to a method of manufacture a magnetic alloy powder for hard magnetic Applications.
- the powder consists of a samarium-cobalt-based alloy.
- the powder can be highly coercive Permanent magnets by hot compaction or Plastic binding can be made. With the powder you can such permanent magnets, however, also powder metallurgy by sintering.
- Sm-Co-based permanent magnets have hitherto been produced primarily by powder metallurgy by sintering (K. Strnat and RMW Strnat, J. Magn. Magn. Mater. 100 (1991) 38).
- To produce the Sm-Co powder required for this it is already known to first melt a corresponding alloy, to comminute it after solidification and to heat-treat it in a passivation gas below the phase transformation temperature of the alloy (US Pat. No. 5,122,203).
- Such a production method has the disadvantage that an energy-consuming and time-consuming multi-stage heat treatment is necessary in order to set high coercive field strengths.
- Such a production method has the disadvantage that additives such as Cu and Zr are necessary for magnets of the Sm 2 Co 17 type in order to set a microstructure which enables a high coercive field strength through the pinning mechanism.
- additives such as Cu and Zr are necessary for magnets of the Sm 2 Co 17 type in order to set a microstructure which enables a high coercive field strength through the pinning mechanism.
- these additives reduce the saturation magnetization.
- the expansion or Stresses caused by the lattice strain lead to inter- and intergranular cracking and eventually to one regular bursting or atomization (Decrepit) the hydrogenated material.
- This The pulverization process can also be affected of vibrations (DE 28 16 538) or by using a Vibratory mill (CH 560 955) are supported.
- the hydrogen is then often removed / desorbed during the further processing of the powder produced into the end product in the course of the subsequent process steps, for example during sintering, in which the reaction A x B y H z ⁇ A x B y + z / 2 H 2 expires.
- This chemical reaction can be represented schematically (using the model substance A x B y mentioned above) as follows: A x B y + z / 2 H 2 ⁇ A x H z + yB
- the hydrogenated alloy elements are then dehydrated again in a second process stage by means of heat treatment under vacuum conditions, with simultaneous recombination of the alloy composition decomposed in stage 1 in accordance with the following reaction equation: A x H z + yB ⁇ A x B y + z / 2 H 2
- the HDDR treatment achieves a crystallite size that is in the range of the single-domain particle size, which is approximately 300 nm for Nd 2 Fe 14 B and Sm 2 Fe 17 N 3, for example.
- This grain refinement which leads to an improvement in the magnetic properties of the magnetic powder, is the main goal of the HDDR treatment and not - as in the HD process - the powder production.
- the HD process is not identical to the first stage of HDDR treatment, as the first two letters of the abbreviation "HDDR" might suggest.
- SE-Fe compounds The increasing stabilization of SE-Fe compounds is also known in the case of substitution of Fe by Co (A. Fujita and I.R. Harris, IEEE Trans. Magn. 30 (1994) 860).
- the invention is based on the object of a method create a technologically manageable and inexpensive manufacture of a hard magnetic, from a Samarium-cobalt-based alloy for existing powder enables high-coercivity permanent magnets.
- the procedure is based on HDDR treatment, in which a Starting powder in a first stage under Hydrogen hydrogenation with disproportionation of Alloy and in a subsequent second process stage under vacuum conditions with hydrogen desorption Recombination of the alloy is subjected.
- a Starting powder in a first stage under Hydrogen hydrogenation with disproportionation of Alloy and in a subsequent second process stage under vacuum conditions with hydrogen desorption Recombination of the alloy is subjected.
- According to the invention becomes a samarium and cobalt containing Starting powder in the first process stage either at a high temperature in the range of 500 ° C to 900 ° C and with a high hydrogen pressure of> 0.5 MPa or else using an intensive fine grinding at a low temperature in the range of 50 ° C to 500 ° C and with treated with a hydrogen pressure of> 0.15 MPa.
- the intensive fine grinding for a period of 1 h to 100 h performed.
- a intensive fine grinding according to the invention a powder of an Sm-Co-based alloy or a powder mixture consisting from the individual elements of an Sm-Co-based alloy and / or consisting of one or more, for the production a Sm-Co-based alloy suitable master alloys, be used.
- the starting powder should be used in the case of a intensive fine grinding preferably with one Hydrogen pressure in the range of 0.5 MPa to 2.5 MPa be finely ground.
- the hydrogen desorption treatment is expedient on the magnetic powder obtained by means of a heat treatment performed in the range of 500 ° C to 1000 ° C.
- those starting powders are preferably used which form magnetic alloy powders with the alloy composition Sm x Co 100-x with 10 ⁇ x ⁇ 30 or the alloy composition Sm x Co 100-xabc Fe a Cu b Zr c with 10 ⁇ x ⁇ 30, a ⁇ 45, b ⁇ 15 and c ⁇ 15.
- a melted Sm 2 (Co, Fe, Cu, Zr) 17 starting alloy as is usually used for the production of Sm-Co sintered magnets and whose coercive field strengths are determined by the pinning mechanism, is crushed down to particle sizes ⁇ 160 ⁇ m and then heated in a hydrogen atmosphere of 2 MPa to a temperature of 600 ° C and held at this temperature for half an hour.
- the powder is hydrogenated by the hydrogen, whereby the alloy is disproportionated.
- the powder is then heated up to 750 ° C with constant pumping and held again at this temperature for half an hour.
- the powder produced in this way has a high coercive field strength H c of approximately 5 kA / cm and can be processed into powerful permanent magnets.
- An SmCo 5 starting alloy is comminuted to particle sizes of ⁇ 500 ⁇ m and then heated in a hydrogen atmosphere of 2 MPa to a temperature of 600 ° C. and held at this temperature for half an hour. The powder is then heated up to 750 ° C with constant pumping and held again at this temperature for half an hour.
- the powder produced in this way has a high coercive field strength H c of approximately 10 kA / cm and can be used for the production of powerful permanent magnets.
- a melted Sm 2 (Co, Fe, Cu, Zr) 17 starting alloy as is usually used for the production of Sm-Co sintered magnets and whose coercive field strengths are determined by the pinning mechanism, is reduced to particle sizes smaller than 160 ⁇ m and then intensively ground with the help of a vibration mill in a hydrogen atmosphere of 1 MPa at a grinding bowl temperature of 350 ° C. for a period of 20 h. In addition to fine grinding, the alloy is disproportionated due to the presence of hydrogen. The powder is then heated to 750.degree. C. to carry out hydrogen desorption while continuously pumping out hydrogen and held at this temperature for half an hour.
- the powder produced in this way has a high coercive field strength H c of approximately 10 kA / cm and can be processed into powerful permanent magnets.
- An SmCo 5 starting alloy is ground down to particle sizes smaller than 500 ⁇ m and then ground with the aid of a vibration mill in a hydrogen atmosphere of 1 MPa at a temperature of the grinding bowl of 350 ° C. for a period of 20 h. In addition to fine grinding, the alloy is disproportionated due to the presence of hydrogen. The powder is then heated to 900 ° C. with the continuous pumping out of hydrogen and kept at this temperature for half an hour in order to carry out a hydrogen desorption.
- the powder produced in this way has a high coercive field strength H c of approximately 30 kA / cm and can be used for the production of powerful permanent magnets.
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- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Hard Magnetic Materials (AREA)
- Powder Metallurgy (AREA)
Description
Die Erfindung bezieht sich auf das Gebiet der metallurgischen Verfahrenstechnik und betrifft ein Verfahren zur Herstellung eines Magnetlegierungspulvers für hartmagnetische Anwendungen. Das Pulver besteht aus einer Samarium-Kobalt-Basis-Legierung. Mit dem Pulver können hochkoerzitive Permanentmagnete durch Heißkompaktierung oder Kunststoffbindung hergestellt werden. Mit dem Pulver können derartige Permanentmagnete jedoch auch auf pulvermetallurgischem Wege durch Sintern erzeugt werden.The invention relates to the field of metallurgical Process engineering and relates to a method of manufacture a magnetic alloy powder for hard magnetic Applications. The powder consists of a samarium-cobalt-based alloy. The powder can be highly coercive Permanent magnets by hot compaction or Plastic binding can be made. With the powder you can such permanent magnets, however, also powder metallurgy by sintering.
Permanentmagnete auf Sm-Co-Basis werden bisher vorwiegend auf pulvermetallurgischem Wege durch Sintern hergestellt (K. Strnat and R. M. W. Strnat, J. Magn. Magn. Mater. 100 (1991) 38). Zur Herstellung des dafür benötigten Sm-Co-Pulvers ist es bereits bekannt, zunächst eine entsprechende Legierung zu erschmelzen, diese nach dem Erstarren zu zerkleinern und in einem Passivierungsgas unterhalb der Phasentransformationstemperatur der Legierung wärmezubehandeln (US 5 122 203). Eine derartige Herstellungsweise hat den Nachteil, daß eine energie- und zeitaufwendige mehrstufige Wärmebehandlung notwendig ist, um hohe Koerzitivfeldstärken einzustellen. Des weiteren hat eine derartige Herstellungsweise den Nachteil, daß für Magnete des Sm2Co17-Typs Additive wie Cu und Zr notwendig sind, um eine Mikrostruktur einzustellen, die eine hohe Koerzitivfeldstärke durch den Pinning-Mechanismus ermöglicht. Diese Additive verringern jedoch die Sättigungsmagnetisierung.Sm-Co-based permanent magnets have hitherto been produced primarily by powder metallurgy by sintering (K. Strnat and RMW Strnat, J. Magn. Magn. Mater. 100 (1991) 38). To produce the Sm-Co powder required for this, it is already known to first melt a corresponding alloy, to comminute it after solidification and to heat-treat it in a passivation gas below the phase transformation temperature of the alloy (US Pat. No. 5,122,203). Such a production method has the disadvantage that an energy-consuming and time-consuming multi-stage heat treatment is necessary in order to set high coercive field strengths. Furthermore, such a production method has the disadvantage that additives such as Cu and Zr are necessary for magnets of the Sm 2 Co 17 type in order to set a microstructure which enables a high coercive field strength through the pinning mechanism. However, these additives reduce the saturation magnetization.
Auf dem Gebiet der Herstellung von Magnetpulvern auf der Basis von Legierungen mit Elementen aus der Gruppe der Seltenen Erden (SE) ist seit langem der HD-Prozess (Hydrid-Dekrepitation) bekannt (US 5 580 396, Spalte 8, Zeilen 30 bis 41; Rare-earth Iron Permanent Magnets, ed. J.M.D. Coey, Oxford 1996, Seiten 346 bis 349 und Seiten 370 bis 380). Dieser Prozess wird eingesetzt zum Zerkleinern von groben, kompakten Legierungskörpern, dient also zur Pulvererzeugung. Dabei wird der Effekt genutzt, dass der in die Zwischenkornphase oder auf die Zwischengitterplätze der SE-Verbindung diffundierte Wasserstoff zu einer Ausdehnung der Zwischenkornphase beziehungsweise zu einer Gitterdehnung der SE-Verbindung führt. Die durch die Ausdehnung bzw. Gitterdehnung hervorgerufenen Spannungen führen zur inter- und intergranularer Rissbildung und schließlich zu einem regelrechten Zerplatzen beziehungsweise Zerstäuben (Dekrepitieren) des hydrierten Materials. Dieser Pulverisierungsvorgang kann auch noch durch die Einwirkung von Vibrationen (DE 28 16 538) oder durch den Einsatz einer Schwingmühle (CH 560 955) unterstützt werden.In the field of magnetic powder production on the Base of alloys with elements from the group of Rare earth (SE) has long been the HD process (hydride decrepitation) known (US 5,580,396, column 8, lines 30 to 41; Rare-earth Iron Permanent Magnets, ed. J.M.D. Coey, Oxford 1996, pages 346 to 349 and pages 370 to 380). This process is used to crush coarse, compact alloy bodies, is used for powder production. The effect is used that the in the Intermediate grain phase or on the interstitial spaces of the SE connection diffused hydrogen to expand the Intermediate grain phase or to a lattice strain of the SE connection leads. The expansion or Stresses caused by the lattice strain lead to inter- and intergranular cracking and eventually to one regular bursting or atomization (Decrepit) the hydrogenated material. This The pulverization process can also be affected of vibrations (DE 28 16 538) or by using a Vibratory mill (CH 560 955) are supported.
Beim Anwenden des HD-Prozesses für eine Verbindung AxBy, in
der A ein Element der Seltenen Erden sei und B für ein oder
mehrere andere Elemente (zumeist Übergangsmetalle) steht,
findet folgende Reaktion statt:
Nach dem eigentlichen HD-Prozess findet dann oftmals bei der Weiterverarbeitung des erzeugten Pulvers zum Endprodukt im Zuge der sich anschließenden Prozessschritte, zum Beispiel beim Sintern, noch ein Entfernen/Desorbieren des Wasserstoffs statt, bei dem die Reaktion AxByHz → AxBy + z/2 H2 abläuft.After the actual HD process, the hydrogen is then often removed / desorbed during the further processing of the powder produced into the end product in the course of the subsequent process steps, for example during sintering, in which the reaction A x B y H z → A x B y + z / 2 H 2 expires.
Es ist auch bereits bekannt, bei der Herstellung von Magnetpulvern aus insbesondere Nd-Fe-B-Legierungen zur Verbesserung der magnetischen Eigenschaften das Verfahren der HDDR (Hydrierung-Disproportionierung-Desorption-Rekombination) anzuwenden (EP 0 304 054; EP 0 516 264; DE 196 07 747). Bei dieser Behandlung wird das Pulver in einer 1. Verfahrensstufe in einer Wasserstoffatmosphäre mit einem niedrigen Druck im Bereich von 0,8 x 105 Pa bis höchstens 0,15 MPa hydriert. Infolge dieser Wasserstoffbehandlung findet eine chemische Reaktion (Disproportionierung) statt, das heißt, die ursprüngliche Phase zerfällt unter Bildung eines binären Hydrids und der übrigen Elemente oder Kombinationen der Elemente der Ausgangsphase.It is also already known to use the process of HDDR (hydrogenation-disproportionation-desorption-recombination) in the production of magnetic powders from in particular Nd-Fe-B alloys to improve the magnetic properties (EP 0 304 054; EP 0 516 264; DE 196 07 747). In this treatment, the powder is hydrogenated in a first process stage in a hydrogen atmosphere at a low pressure in the range from 0.8 × 10 5 Pa to at most 0.15 MPa. As a result of this hydrogen treatment, a chemical reaction (disproportionation) takes place, that is, the original phase breaks down to form a binary hydride and the other elements or combinations of the elements of the starting phase.
Diese chemische Reaktion kann schematisch (unter analoger
Verwendung der obengenannten Modellsubstanz AxBy) wie folgt
dargestellt werden:
Anschließend werden dann in einer 2. Verfahrensstufe mittels
einer Wärmebehandlung unter Vakuumbedingungen die hydrierten
Legierungselemente wieder dehydriert, bei gleichzeitiger
Rekombination der in Stufe 1 zersetzten Legierungszusammensetzung
gemäß folgender Reaktionsgleichung:
Durch die HDDR-Behandlung wird eine Kristallitgröße erreicht, die im Bereich der Eindomänenteilchengröße liegt, die z.B. für Nd2Fe14B und Sm2Fe17N3 etwa 300 nm beträgt. Diese Kornfeinung, die zu einer Verbesserung der magnetischen Eigenschaften des Magnetpulvers führt, ist das Hauptziel der HDDR-Behandlung und nicht - wie beim HD-Prozess - die Pulverherstellung. An dieser Stelle sei ausdrücklich darauf hingewiesen, dass der HD-Prozess nicht mit der ersten Stufe der HDDR-Behandlung identisch ist, wie die ersten beiden Buchstaben der Abkürzung "HDDR" eventuell suggerieren könnten.The HDDR treatment achieves a crystallite size that is in the range of the single-domain particle size, which is approximately 300 nm for Nd 2 Fe 14 B and Sm 2 Fe 17 N 3, for example. This grain refinement, which leads to an improvement in the magnetic properties of the magnetic powder, is the main goal of the HDDR treatment and not - as in the HD process - the powder production. At this point it should be expressly pointed out that the HD process is not identical to the first stage of HDDR treatment, as the first two letters of the abbreviation "HDDR" might suggest.
In der HDDR-Stufe 1 kommt es beim Aufheizen bis zu den für die oben dargestellte Reaktion notwendigen Temperaturen von 500°C bis 1000°C zwar oft zu der für den HD-Prozess typischen Wasserstoffabsorption wie sie oben in der Gleichung für den HD-Prozess beschrieben ist, jedoch stellt dies nur eine Zwischenreaktion dar, der unmittelbar die Desorption des Wasserstoffs folgt. Die HDDR-Behandlung kann völlig unabhängig vom HD-Prozess durchgeführt werden, wie zum Beispiel mit dem "solid-HDDR"-Prozess gezeigt wurde, bei dem das Wasserstoffgas erst bei der für die Disproportionierung (HDDR-Stufe 1) notwendigen Temperatur in den Reaktor eingelassen wird und es so zu keiner interstitiellen Absorption des Wasserstoffs und damit nicht zum HD-Prozess kommt (Gutfleisch et al., J. Alloys Compd. 215 (1994) 227).In the HDDR stage 1, when heating up to the for the reaction shown above necessary temperatures of 500 ° C to 1000 ° C is often the typical one for the HD process Hydrogen absorption as shown in the equation for the above HD process is described, however, this represents only one Intermediate reaction, which directly the desorption of the Hydrogen follows. The HDDR treatment can completely regardless of the HD process, such as Example with the "solid-HDDR" process was shown, in which the hydrogen gas only for disproportionation (HDDR stage 1) necessary temperature in the reactor is admitted and there is no interstitial Absorption of hydrogen and therefore not to the HD process comes (Gutfleisch et al., J. Alloys Compd. 215 (1994) 227).
Bekannt ist auch die zunehmende Stabilisierung von SE-Fe-Verbindungen im Falle der Substitution des Fe durch Co (A. Fujita and I. R. Harris, IEEE Trans. Magn. 30 (1994) 860).The increasing stabilization of SE-Fe compounds is also known in the case of substitution of Fe by Co (A. Fujita and I.R. Harris, IEEE Trans. Magn. 30 (1994) 860).
Eine Übertragung der für Nd-Fe-B-Magnetpulver bekannten HDDR-Verfahrensbedingungen auf Sm-Co-Magnetpulver ist nicht möglich, da eine Disproportionierungsreaktion, wie sie in der oben dargestellten Stufe 1 der HDDR-Behandlung stattfindet, unter den üblichen HDDR-Bedingungen (500 < T < 1000°C, ~0,1 MPa Wasserstoffdruck) bei Sm-Co-Magnetpulvern wegen der großen Stabilität dieser Legierungen nicht eintritt.A transfer of the HDDR process conditions known for Nd-Fe-B magnetic powder on Sm-Co magnetic powder is not possible because of a disproportionation reaction as in the stage 1 of HDDR treatment shown above takes place, under the usual HDDR conditions (500 <T <1000 ° C, ~ 0.1 MPa hydrogen pressure) for Sm-Co magnetic powders because of the great stability of these alloys does not occur.
Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren zu schaffen, das eine technologisch beherrschbare und kostengünstige Herstellung eines hartmagnetischen, aus einer Samarium-Kobalt-Basis-Legierung bestehenden Pulvers für hochkoerzitive Permanentmagnete ermöglicht.The invention is based on the object of a method create a technologically manageable and inexpensive manufacture of a hard magnetic, from a Samarium-cobalt-based alloy for existing powder enables high-coercivity permanent magnets.
Diese Aufgabe wird nach der Erfindung mit dem in den Patentansprüchen beschriebenen Herstellungsverfahren gelöst.This object is achieved according to the invention with that in the claims described manufacturing process solved.
Das Verfahren basiert auf einer HDDR-Behandlung , bei der ein Ausgangspulver in einer ersten Verfahrensstufe unter Wasserstoff einer Hydrierung mit Disproportionierung der Legierung und in einer anschließenden zweiten Verfahrensstufe unter Vakuumbedingungen einer Wasserstoffdesorption mit Rekombination der Legierung unterworfen wird. Erfindungsgemäß wird dabei ein Samarium und Kobalt enthaltendes Ausgangspulver in der ersten Verfahrensstufe entweder bei einer hohen Temperatur im Bereich von 500 °C bis 900 °C und mit einem hohen Wasserstoffdruck von > 0,5 MPa oder aber unter Anwendung einer intensiven Feinmahlung bei einer niedrigen Temperatur im Bereich von 50 °C bis 500 °C und mit einem Wasserstoffdruck von > 0,15 MPa behandelt.The procedure is based on HDDR treatment, in which a Starting powder in a first stage under Hydrogen hydrogenation with disproportionation of Alloy and in a subsequent second process stage under vacuum conditions with hydrogen desorption Recombination of the alloy is subjected. According to the invention becomes a samarium and cobalt containing Starting powder in the first process stage either at a high temperature in the range of 500 ° C to 900 ° C and with a high hydrogen pressure of> 0.5 MPa or else using an intensive fine grinding at a low temperature in the range of 50 ° C to 500 ° C and with treated with a hydrogen pressure of> 0.15 MPa.
Beide Verfahrensvarianten führen zur Disproportionierung der Ausgangsphase und zur Bildung eines kristallinen binären Samarium-Hydrids.Both process variants lead to disproportionation of the Initial phase and to form a crystalline binary Samarium hydrides.
Im Falle der Anwendung der hohen Temperatur im Bereich von 500 °C bis 900 °C wird vorzugsweise ein Wasserstoffdruck im Bereich von 1,0 MPa bis 5,0 MPa angewandt. In case of using high temperature in the range of 500 ° C to 900 ° C is preferably a hydrogen pressure in the Range from 1.0 MPa to 5.0 MPa applied.
Gemäß einer zweckmäßigen Ausgestaltung des Verfahrens wird die intensive Feinmahlung während einer Dauer von 1 h bis 100 h durchgeführt.According to an expedient embodiment of the method the intensive fine grinding for a period of 1 h to 100 h performed.
Als Ausgangspulver kann im Falle der Anwendung einer intensiven Feinmahlung erfindungsgemäß ein Pulver einer Sm-Co-Basis-Legierung oder aber eine Pulvermischung, bestehend aus den einzelnen Elementen einer Sm-Co-Basis-Legierung und/oder bestehend aus einer oder mehreren, zur Herstellung einer Sm-Co-Basis-Legierung geeigneten Vorlegierungen, eingesetzt werden.As a starting powder, a intensive fine grinding according to the invention a powder of an Sm-Co-based alloy or a powder mixture consisting from the individual elements of an Sm-Co-based alloy and / or consisting of one or more, for the production a Sm-Co-based alloy suitable master alloys, be used.
Das Ausgangspulver sollte im Falle der Anwendung einer intensiven Feinmahlung vorzugsweise bei einem Wasserstoffdruck im Bereich von 0,5 MPa bis 2,5 MPa feingemahlen werden.The starting powder should be used in the case of a intensive fine grinding preferably with one Hydrogen pressure in the range of 0.5 MPa to 2.5 MPa be finely ground.
Zweckmäßigerweise wird die Wasserstoffdesorptionsbehandlung an dem erhaltenen Magnetpulver mittels einer Wärmebehandlung im Bereich von 500 °C bis 1000 °C durchgeführt.The hydrogen desorption treatment is expedient on the magnetic powder obtained by means of a heat treatment performed in the range of 500 ° C to 1000 ° C.
Nach der Erfindung werden bevorzugt solche Ausgangspulver eingesetzt, die zu Magnetlegierungspulvern mit der Legierungszusammensetzung SmxCo100-x mit 10 < x < 30 oder der Legierungszusammensetzung SmxCo100-x-a-b-cFeaCubZrc mit 10 < x < 30, a < 45, b < 15 und c < 15 führen.According to the invention, those starting powders are preferably used which form magnetic alloy powders with the alloy composition Sm x Co 100-x with 10 <x <30 or the alloy composition Sm x Co 100-xabc Fe a Cu b Zr c with 10 <x <30, a <45, b <15 and c <15.
Mit dem erfindungsgemäßen Verfahren wird eine neue Möglichkeit für die magnetische Härtung von Sm-Co-BasisVerbindungen geschaffen. Durch das Verfahren ergeben sich neue Ansätze für eine Optimierung der magnetischen Eigenschaften von Sm-Co-Magneten, die zu einer Verbesserung der Eigenschaften führt und eine kostengünstige Alternative für die Herstellung solcher Magnete darstellt. Dies schließt die Möglichkeit einer Homogenisierung der Mikrostruktur der Sm-Co-Basisverbindungen ein, wodurch eine langwierige Homogenisierung bei hohen Temperaturen entfallen kann.With the method according to the invention, a new one Possibility for magnetic hardening of Sm-Co base connections created. The procedure results in new approaches to optimize magnetic Properties of Sm-Co magnets that lead to an improvement of properties and an inexpensive alternative represents for the manufacture of such magnets. This closes the possibility of homogenization of the microstructure of the Sm-Co base compounds, creating a lengthy Homogenization at high temperatures can be omitted.
Nachstehend ist die Erfindung an Hand von Ausführungsbeispielen näher erläutert.The invention is described below with the aid of Exemplary embodiments explained in more detail.
Eine erschmolzene Sm2 (Co, Fe, Cu, Zr)17-Ausgangslegierung, wie sie üblicherweise für die Herstellung von Sm-Co Sintermagneten verwendet wird und deren Koerzitivfeldstärken durch den Pinning-Mechanismus bestimmt werden, wird bis auf Partikelgrößen < 160 µm zerkleinert und anschließend in einer Wasserstoffatmosphäre von 2 MPa bis zu einer Temperatur von 600°C aufgeheizt und eine halbe Stunde bei dieser Temperatur gehalten. Durch den Wasserstoff wird das Pulver hydriert, wobei eine Disproportionierung der Legierung stattfindet. Anschließend wird das Pulver unter ständigem Abpumpen bis 750°C aufgeheizt und bei dieser Temperatur erneut eine halbe Stunde gehalten.A melted Sm 2 (Co, Fe, Cu, Zr) 17 starting alloy, as is usually used for the production of Sm-Co sintered magnets and whose coercive field strengths are determined by the pinning mechanism, is crushed down to particle sizes <160 µm and then heated in a hydrogen atmosphere of 2 MPa to a temperature of 600 ° C and held at this temperature for half an hour. The powder is hydrogenated by the hydrogen, whereby the alloy is disproportionated. The powder is then heated up to 750 ° C with constant pumping and held again at this temperature for half an hour.
Das so hergestellte Pulver weist eine hohe Koerzitivfeldstärke Hc von etwa 5 kA/cm auf und kann zu leistungsfähigen Permanentmagneten verarbeitet werden.The powder produced in this way has a high coercive field strength H c of approximately 5 kA / cm and can be processed into powerful permanent magnets.
Eine SmCo5 Ausgangslegierung wird bis auf Partikelgrößen < 500 um zerkleinert und anschließend in einer Wasserstoffatmosphäre von 2 MPa bis zu einer Temperatur von 600°C aufgeheizt und eine halbe Stunde bei dieser Temperatur gehalten. Anschließend wird das Pulver unter ständigem Abpumpen bis 750°C aufgeheizt und bei dieser Temperatur erneut eine halbe Stunde gehalten.An SmCo 5 starting alloy is comminuted to particle sizes of <500 μm and then heated in a hydrogen atmosphere of 2 MPa to a temperature of 600 ° C. and held at this temperature for half an hour. The powder is then heated up to 750 ° C with constant pumping and held again at this temperature for half an hour.
Das auf diese Weise hergestellte Pulver weist eine hohe Koerzitivfeldstärke Hc von etwa 10 kA/cm auf und ist für die Herstellung leistungsfähiger Permanentmagnete verwendbar.The powder produced in this way has a high coercive field strength H c of approximately 10 kA / cm and can be used for the production of powerful permanent magnets.
Eine erschmolzene Sm2(Co,Fe,Cu,Zr)17 Ausgangslegierung, wie sie üblicherweise für die Herstellung von Sm-Co-Sintermagneten verwendet wird und deren Koerzitivfeldstärken durch den Pinning-Mechanismus bestimmt werden, wird bis auf Partikelgrößen kleiner 160 µm zerkleinert und anschließend mit Hilfe einer Vibrationsmühle in einer Wasserstoffatmosphäre von 1 MPa bei einer Temperatur des Mahlbechers von 350°C während einer Dauer von 20 h intensiv gemahlen. Hierbei findet neben einer Feinmahlung gleichzeitig infolge des anwesenden Wasserstoffs eine Disproportionierung der Legierung statt. Anschließend wird das Pulver zur Durchführung einer Wasserstoffdesorption unter ständigem Abpumpen von Wasserstoff bis auf 750°C aufgeheizt und bei dieser Temperatur eine halbe Stunde gehalten.A melted Sm 2 (Co, Fe, Cu, Zr) 17 starting alloy, as is usually used for the production of Sm-Co sintered magnets and whose coercive field strengths are determined by the pinning mechanism, is reduced to particle sizes smaller than 160 µm and then intensively ground with the help of a vibration mill in a hydrogen atmosphere of 1 MPa at a grinding bowl temperature of 350 ° C. for a period of 20 h. In addition to fine grinding, the alloy is disproportionated due to the presence of hydrogen. The powder is then heated to 750.degree. C. to carry out hydrogen desorption while continuously pumping out hydrogen and held at this temperature for half an hour.
Das auf diese Weise hergestellte Pulver weist eine hohe Koerzitivfeldstärke Hc von etwa 10 kA/cm auf und kann zu leistungsfähigen Permanentmagneten verarbeitet werden.The powder produced in this way has a high coercive field strength H c of approximately 10 kA / cm and can be processed into powerful permanent magnets.
Eine SmCo5 Ausgangslegierung wird bis auf Partikelgrößen kleiner 500 µm zerkleinert und anschließend mit Hilfe einer Vibrationsmühle in einer Wasserstoffatmosphäre von 1 MPa bei einer Temperatur des Mahlbechers von 350°C während einer Dauer von 20 h intensiv gemahlen. Hierbei findet neben einer Feinmahlung gleichzeitig infolge des anwesenden Wasserstoffs eine Disproportionierung der Legierung statt. Anschließend wird das Pulver zur Durchführung einer Wasserstoffdesorption unter ständigem Abpumpen von Wasserstoff bis auf 900°C aufgeheizt und bei dieser Temperatur eine halbe Stunde gehalten.An SmCo 5 starting alloy is ground down to particle sizes smaller than 500 µm and then ground with the aid of a vibration mill in a hydrogen atmosphere of 1 MPa at a temperature of the grinding bowl of 350 ° C. for a period of 20 h. In addition to fine grinding, the alloy is disproportionated due to the presence of hydrogen. The powder is then heated to 900 ° C. with the continuous pumping out of hydrogen and kept at this temperature for half an hour in order to carry out a hydrogen desorption.
Das auf diese Weise hergestellte Pulver weist eine hohe Koerzitivfeldstärke Hc von etwa 30 kA/cm auf und ist für die Herstellung leistungsfähiger Permanentmagnete verwendbar.The powder produced in this way has a high coercive field strength H c of approximately 30 kA / cm and can be used for the production of powerful permanent magnets.
Claims (8)
- Method for producing a magnetic alloy powder for hard magnetic applications by subjecting an initial powder to an HDDR treatment in which, in a first stage of the method, hydrogenation is carried out in a hydrogen atmosphere with disproportionation of the alloy and, in a subsequent second stage of the method, hydrogen desorption is carried out under vacuum conditions with recombination of the alloy, characterized in that an initial powder containing samarium and cobalt is treated, in the first stage of the method, either at a high temperature in the range of from 500°C to 900°C and with a high hydrogen pressure of > 0.5 MPa or alternatively, by application of intensive fine grinding, at a low temperature in the range of from 50°C and 500°C and with a hydrogen pressure of > 0.15 MPa.
- Method according to Claim 1, characterized in that, in the case of applying the high temperature in the range of from 500°C to 900°C, a hydrogen pressure in the range of from 1.0 MPa to 5.0 MPa is applied.
- Method according to Claim 1, characterized in that the intensive fine grinding is performed for a period of from 1 h to 100 h.
- Method according to Claim 1, characterized in that, in the case of applying intensive fine grinding, an Sm-Co based alloy or a powder mixture, consisting of the individual elements of an Sm-Co based alloy and/or consisting of one or more prealloys suitable for the production of an Sm-Co based alloy, is used as the initial powder.
- Method according to Claim 1, characterized in that, in the case of applying intensive fine grinding, the initial powder is finely ground at a hydrogen pressure in the range of from 0.5 MPa to 2.5 MPa.
- Method according to Claim 1, characterized in that the hydrogen desorption treatment is performed by means of a heat treatment in the range of from 500°C to 1000°C.
- Method according to Claim 1, characterized in that a magnetic alloy powder is produced in the alloy composition SmxCo100-x with 10 < x < 30.
- Method according to Claim 1, characterized in that a magnetic alloy powder is produced in the alloy composition SmxCo100-x-a-b-cFeaCubZrc with 10 < x < 30, a < 45, b < 15 and c < 15.
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DE19751367 | 1997-11-20 | ||
DE19751366 | 1997-11-20 | ||
DE19751367A DE19751367C2 (en) | 1997-11-20 | 1997-11-20 | Process for producing a hard magnetic powder consisting of a samarium-cobalt-based alloy |
DE1997151366 DE19751366C2 (en) | 1997-11-20 | 1997-11-20 | Process for the production of a hard magnetic samarium-cobalt base material |
PCT/EP1998/007418 WO1999027544A1 (en) | 1997-11-20 | 1998-11-19 | Method for producing a magnetic alloy powder |
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EP1032940A1 EP1032940A1 (en) | 2000-09-06 |
EP1032940B1 true EP1032940B1 (en) | 2001-09-12 |
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US (1) | US6352597B1 (en) |
EP (1) | EP1032940B1 (en) |
JP (1) | JP2001524604A (en) |
DE (1) | DE59801474D1 (en) |
WO (1) | WO1999027544A1 (en) |
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DE102012200850A1 (en) * | 2012-01-20 | 2013-07-25 | Robert Bosch Gmbh | Method for producing a magnetic material and permanent magnet |
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US8637198B2 (en) * | 2009-12-24 | 2014-01-28 | Konica Minolta Holdings, Inc. | Reaction container and fuel cell system equipped with same |
CN103050268B (en) * | 2012-12-31 | 2016-01-20 | 厦门钨业股份有限公司 | Heat treated sintered Nd-Fe-B based magnet manufacture method is steamed based on fine powder |
CN103050267B (en) * | 2012-12-31 | 2016-01-20 | 厦门钨业股份有限公司 | A kind of based on fine powder heat treated sintered Nd-Fe-B based magnet manufacture method |
CZ2014766A3 (en) * | 2014-11-07 | 2016-02-10 | Vysoká škola chemicko- technologická v Praze | Production of nanostructured powders of cobalt alloys by two-stage mechanical alloy building |
CN111180157B (en) * | 2019-12-24 | 2021-04-06 | 中国计量大学 | A method of manufacturing a semiconductor device, comprises the following steps: 17-type SmCoCuFeZrB sintered permanent magnet and preparation method thereof |
CN115938718B (en) * | 2023-03-09 | 2023-05-30 | 天通控股股份有限公司 | Direct-insert integrated cofiring inductor and preparation method thereof |
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GB1554384A (en) * | 1977-04-15 | 1979-10-17 | Magnetic Polymers Ltd | Rare earth metal alloy magnets |
US5143560A (en) * | 1990-04-20 | 1992-09-01 | Hitachi Metals, Inc., Ltd. | Method for forming Fe-B-R-T alloy powder by hydrogen decrepitation of die-upset billets |
US5474623A (en) * | 1993-05-28 | 1995-12-12 | Rhone-Poulenc Inc. | Magnetically anisotropic spherical powder and method of making same |
US5851312A (en) * | 1996-02-26 | 1998-12-22 | Aichi Steel Works, Ltd. | Production method, production apparatus and heat treatment apparatus for anisotropic magnet powder |
JP2881409B2 (en) * | 1996-10-28 | 1999-04-12 | 愛知製鋼株式会社 | Method for producing anisotropic magnet powder |
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- 1998-11-19 WO PCT/EP1998/007418 patent/WO1999027544A1/en active IP Right Grant
- 1998-11-19 EP EP98956933A patent/EP1032940B1/en not_active Expired - Lifetime
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DE102012200850A1 (en) * | 2012-01-20 | 2013-07-25 | Robert Bosch Gmbh | Method for producing a magnetic material and permanent magnet |
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DE59801474D1 (en) | 2001-10-18 |
EP1032940A1 (en) | 2000-09-06 |
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JP2001524604A (en) | 2001-12-04 |
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