EP0200079B1 - Préparation d'une ébauche métallique d'un alliage amorphe - Google Patents

Préparation d'une ébauche métallique d'un alliage amorphe Download PDF

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Publication number
EP0200079B1
EP0200079B1 EP86105131A EP86105131A EP0200079B1 EP 0200079 B1 EP0200079 B1 EP 0200079B1 EP 86105131 A EP86105131 A EP 86105131A EP 86105131 A EP86105131 A EP 86105131A EP 0200079 B1 EP0200079 B1 EP 0200079B1
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EP
European Patent Office
Prior art keywords
process according
alloy
mixed powder
intermediate product
alloy components
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
EP86105131A
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German (de)
English (en)
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EP0200079A1 (fr
Inventor
Ludwig Dr. Schultz
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Siemens AG
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Siemens AG
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C45/00—Amorphous alloys
    • 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
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/14—Treatment of metallic powder
    • B22F1/142—Thermal or thermo-mechanical treatment
    • 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
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/006—Amorphous articles
    • B22F3/007—Amorphous articles by diffusion starting from non-amorphous articles prepared by powder metallurgy
    • 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
    • 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
    • B22F2009/041—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by mechanical alloying, e.g. blending, milling

Definitions

  • Such a method is e.g. from WO-A 84/02 926.
  • Amorphous materials referred to as "metallic glasses” are generally known (cf. for example "Zeitschrift für Metallischen), volume 69, 1978, number 4, pages 212 to 220 or “Elektrotechnik und Maschinenbau", 97th year, September 1980, number 9, Pages 378 to 385). These materials are generally special alloys which are to be produced from at least two predetermined starting elements or compounds, also referred to as alloy components, by means of special processes. These special alloys have a glass-like, amorphous structure instead of a crystalline one and have a number of extraordinary properties or combinations of properties such as high wear and corrosion resistance, high hardness and tensile strength with good ductility as well as special magnetic properties. In addition, the amorphous state can be used to produce microcrystalline materials with interesting properties (see e.g. DE-C 2 834425).
  • metallic glasses have generally been produced by rapid quenching from the melt (cf. also DE-A 3 135 374 or DE-A 3 128 063).
  • this method results in at least one dimension of the material produced being less than about 0.1 mm.
  • metallic glasses of any shape and size were available.
  • a certain microstructure is also required, in that the alloy components involved are closely adjacent and each have very small dimensions below 1 J.Lm in at least one dimension.
  • layer structures are particularly suitable, which can be produced, for example, by vapor deposition (see, for example, the cited reference from "Phys. Rev. Letters", Vol. 51).
  • layering of thin metal foils is also possible for this (cf. e.g. "Proc. MRS Europe Meeting on Amorphous Metals and Non-Equilibrium Processing", ed. M. von Allen, France, 1984, pages 135 to 140).
  • a corresponding microstructure is also formed in the method according to WO-A 84/02 926 mentioned at the outset.
  • metal alloys of the desired composition are first mixed as alloy components and then compacted to an intermediate product in such a way that the alloy components are each expanded in at least one dimension by at most 1 J.Lm.
  • This intermediate product is then converted into the desired metallic body with an amorphous structure by anomalous rapid diffusion at a predetermined elevated temperature (cf. also "Frankfurter Science: Magnolia Kunststoff die Boat”, published by: “Frankfurter Med", 27th year, no. 23, 1.2.1984, page 5 or "Machine Design", Vol. 55, No. 25, 10.10.1983, page 8).
  • the object of the present invention is to design the method mentioned at the outset in such a way that it can be used to produce large-scale metallic bodies with a relatively extensive shape and dimension from amorphous alloys, and in particular difficult to deform or brittle alloy components.
  • a mixed powder is produced from the mostly crystalline powders of the starting elements or compounds representing the alloy components, the individual particles of which are built up in layers from the starting elements or compounds.
  • the point in time at the end of the grinding process at which this structure of the mixed powder particles is present can easily be determined and thus determined, for example by experimental examination of the particles.
  • This mixed powder produced in this way is then compacted and / or deformed in a further working step to form a compact intermediate product with the desired shape and size adapted to the body.
  • This compact intermediate product still consists of crystalline parts of the starting elements or compounds, the dimensions of which in at least one dimension are less than 1 J.Lm.
  • the intermediate product is then converted into the desired metallic body with the amorphous alloy in a manner known per se. Since there are practically no restrictions with regard to the expansion of the intermediate product to be made from it when compacting the mixed powder, the advantages associated with the method according to the invention can be seen in particular in that with this method metallic bodies of amorphous alloys with larger expansions can be produced on a large industrial scale in a relatively simple manner have it made.
  • the invention is further explained below on the basis of the production of a body from a metallic glass.
  • the at least two powdery alloy components do not necessarily all have to be metallic, but in some cases can also be metalloids. Generally these components will be crystalline; however, amorphous powders can also be provided in the special cases of using metalloids.
  • a predetermined temperature level below the crystallization temperature of the amorphous material to be formed can advantageously be maintained. If necessary, several temperature levels can also be provided or a corresponding temperature program can be expedient.
  • As the grinding time progresses larger powder particles are formed which at least largely have a layer-like structure, ie consist of a multiplicity of alternating layer-like regions of the alloy components involved. This is therefore a microstructure of the type that also arises, for example, in the initial phase of a known method for mechanical alloying (cf., for example, "Scientific American", vol. 234, 1976, pages 40 to 48). According to this known method, amorphous alloys can also be produced per se (see, for example, "Applied Physics Letters", Vol. 43, No.
  • the grinding process is achieved when the layer-like structure mentioned is reached, in which the layer-like areas in generally about 0.01 to 0.9 gm, preferably between 0.05 and 0.5 ⁇ m thick.
  • the size of the powder particles themselves is about 10 to 200 J.Lm diameter.
  • the predetermined point in time at which this desired structure of the powder particles is present can be determined, for example, by section examinations of the particles.
  • This reaction can, if appropriate, take place as an anomalous, rapid diffusion in a known manner, one alloy component diffusing into the other.
  • other diffusion reactions with, for example, mutual diffusion of the components are also possible.
  • the annealing temperature must in any case be below the crystallization temperature of the metallic glass in a known manner. The one at the end of this procedure Rens, as the end product, thus consists of an amorphous alloy with a thickness and shape that is predetermined by the compacting process and can therefore be chosen as desired.
  • the compaction and the diffusion treatment can also be carried out in one step, for example by hot extrusion. It is important to ensure that the powder is only heated immediately before it is deformed, otherwise the amorphous phase will form before the extrusion and thus a good compaction would be hindered.
  • one or both alloy components can themselves consist of an alloy or a combination of several elements.
  • one of the alloy components consists of a non-deformable powder such as Boron for a mixture of Fe and B powders
  • the B powder particles are installed between the Fe layers.
  • the B particles should be less than 1 J.Lm. It is advantageous for thermodynamic reasons to use B powder in the amorphous state.
  • Ni powder and Zr powder each with powder particle sizes of, for example, an average of about 40 ⁇ m each, are placed in a powder mill (eg, Fritsch brand, type "Pulverisette-5") and with the help of their steel balls, each have a diameter of 10 mm, grind.
  • a powder mill eg, Fritsch brand, type "Pulverisette-5
  • Fritsch brand, type "Pulverisette-5” e.g. Fritsch brand, type "Pulverisette-5”
  • These particles grow with increasing grinding time up to a maximum particle size of about 20 to 100 microns in diameter. Looking at these particles in section, it can be seen that they then have an approximately layered structure made of the two materials Ni and Zr, the respective layer thicknesses being less than 1 gm.
  • these particles thus form the desired mixed powder, so that the grinding process is ended at this time. If grinding continued, these mixed powder particles would be ground again, ie the layered structure of the two alloy components required for the process according to the invention would be destroyed. Subsequently, steel tubes with an inner diameter of 15 mm and a wall thickness of 2.5 mm are filled with the mixed powder thus obtained, and the powder is compacted, and sealed. By hammering, the steel tubes are then shaped with their cores from the mixed powder of the two alloy components to the desired dimensions of the strip to be produced. For example, the core is brought to a thickness of 1 mm.
  • the thus shaped, now band-shaped structures are then subjected to diffusion annealing below the crystallization temperature of the desired amorphous material, for example at 300 ° C. for about 24 hours. If Co instead of Ni were used, the temperature to be selected would be around 240 ° C. After removing the steel sheath that was still present, for example by etching with dilute hydrochloric acid, the desired band made of the amorphous NiZr alloy with a relatively large thickness of about 1 is then located mm before and can finally be processed in a known manner.
  • the metallic body to be created is an amorphous, i.e. non-crystalline structure, in particular that of a metallic glass.
  • the method according to the invention can also be particularly advantageously provided for the production of microcrystalline materials by way of a detour of the amorphous state.
  • intermediate products from Nd-Fe-B alloys are first produced in amorphous form according to the invention. This alloy is then crystallized in a subsequent annealing treatment.
  • the resulting microcrystalline structure has excellent hard magnetic properties (see, for example, "Applied Physics Letters", Vol. 44, No. 1, January 1984, pages 148 and 149).

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Metallurgy (AREA)
  • Materials Engineering (AREA)
  • Thermal Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
  • Hard Magnetic Materials (AREA)
  • Soft Magnetic Materials (AREA)

Claims (14)

1. Procédé de préparation d'un corps métallique en un alliage amorphe, notamment en un verre métallique, procédé dans lequel sont à effectuer les phases opératoires suivantes:
A) On forme, en effectuant une phase de compactage, un produit intermédiaire à partir d'au moins deux constituants pulvérulents de l'alliage, de façon que les constituants de l'alliage s'étendent chacun, dans le produit intermédiaire, au moins suivant une dimension sur 1 µm au plus, et
B) on transforme le produit intermédiaire en le corps métallique dans lequel l'alliage est à l'état amorphe, au moyen d'une réaction de diffusion, à une température élevée prescrite qui est inférieure à la température de cristallisation de l'alliage amorphe,

caractérisé en ce que, pour effectuer la phase opératoire A) du procédé, on prépare, à partir des constituants pulvérulents de l'alliage et au moyen d'un processus de broyage à achever à un instant prescrit, de telle façon une poudre de mélange ayant des particules, que ces particules de poudre de mélange présentent respectivement, au moins très largement, une structure stratiforme en les constituants de l'alliage et qu'ensuite on compacte, et, le cas échéant, on déforme ces particules de poudre de mélange en le produit intermédiaire ayant la forme et les dimensions souhaitées.
2. Procédé suivant la revendication 1, caractérisé en ce qu'il consiste à déterminer l'achèvement du processus de broyage expérimentalement, au moyen d'un examen des particules de la poudre de mélange.
3. Procédé suivant la revendication 1 ou 2, caractérisé en ce qu'il consiste à broyer sous gaz protecteur les constituants pulvérulents de l'alliage- en la poudre de mélange.
4. Procédé suivant l'une des revendications 1 à 3, caractérisé en ce qu'il consiste à broyer les constituants de l'alliage en la poudre de mélange à au moins une température prescrite.
5. Procédé suivant l'une des revendications 1 à 4, caractérisé en ce qu'il consiste à broyer les constituants pulvérulents de l'alliage jusqu'à ce que les particules de la poudre de mélange présentent des épaisseurs comprises entre 0,01 µm et 0,9 µm et, de préférence, comprises entre 0,05 J.Lm et 0,5 lim.
6. Procédé suivant l'une des revendications 1 à 5, caractérisé en ce qu'il consiste à broyer les constituants pulvérisants de l'alliage en des particules de poudre de mélange ayant des diamètres de particules compris entre 10 et 200 J.Lm environ et, de préférence, entre 20 et 100 µm environ.
7. Procédé suivant l'une des revendications 1 à 6, caractérisé en ce qu'il consiste à conformer la poudre de mélange en le produit intermédiaire par martelage ou par extrusion.
8. Procédé suivant l'une des revendications 1 à 7, caractérisé en ce qu'il consiste à effectuer la réaction de diffusion après la dernière phase opératoire de compactage ou de déformation.
9. Procédé suivant l'une des revendications 1 à 7, caractérisé en ce qu'il consiste à effectuer la réaction de diffusion en même temps que la dernière phase opératoire de compactage ou de déformation.
10. Procédé suivant l'une des revendications 1 à 9, caractérisé en ce qu'il consiste à transformer la texture non cristalline du produit intermédiaire en une texture microcristalline par un traitement de recuit prédéterminé.
11. Procédé suivant l'une des revendications 1 à 10, caractérisé en ce que le produit intermédiaire est constitué d'au moins deux constituants cristallins de l'alliage.
12. Procédé suivant l'une des revendications 1 à 10, caractérisé en ce qu'il consiste à prévoir, outre au moins un élément de départ métallique, ou un composé de départ métallique comme l'un des constituants de l'alliage, au moins un autre élément de départ ou au moins un autre composé de départ comme autre constituant de l'alliage, qui est un métalloïde.
13. Procédé suivant la revendication 12, caractérisé en ce qu'il consiste à prévoir comme métalloïde une poudre amorphe.
14. Procédé suivant l'une des revendications 1 à 13, caractérisé en ce qu'il consiste à prévoir, comme au moins un constituant de départ, un composé ou un alliage de plusieurs éléments.
EP86105131A 1985-04-26 1986-04-14 Préparation d'une ébauche métallique d'un alliage amorphe Expired - Lifetime EP0200079B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853515167 DE3515167A1 (de) 1985-04-26 1985-04-26 Verfahren zur herstellung eines metallischen koerpers aus einer amorphen legierung
DE3515167 1985-04-26

Publications (2)

Publication Number Publication Date
EP0200079A1 EP0200079A1 (fr) 1986-11-05
EP0200079B1 true EP0200079B1 (fr) 1990-03-14

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EP86105131A Expired - Lifetime EP0200079B1 (fr) 1985-04-26 1986-04-14 Préparation d'une ébauche métallique d'un alliage amorphe

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US (1) US4710236A (fr)
EP (1) EP0200079B1 (fr)
JP (1) JPS61250122A (fr)
DE (2) DE3515167A1 (fr)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3535065A1 (de) * 1985-10-01 1987-04-09 Siemens Ag Verfahren zur herstellung eines metallischen koerpers aus einer amorphen legierung
EP0232772B1 (fr) * 1986-02-05 1989-12-27 Siemens Aktiengesellschaft Procédé de préparation d'un matériau pulvérulent amorphe par un procédé de broyage
DE3763888D1 (de) * 1986-03-27 1990-08-30 Siemens Ag Verfahren zur herstellung eines dauermagnetwerkstoffes aus pulverfoermigen ausgangskomponenten.
US4737340A (en) * 1986-08-29 1988-04-12 Allied Corporation High performance metal alloys
DE3709138C2 (de) * 1987-03-20 1996-09-05 Siemens Ag Verfahren zur Herstellung eines magnetischen Werkstoffes aus pulverförmigen Ausgangskomponenten
US4762677A (en) * 1987-11-03 1988-08-09 Allied-Signal Inc. Method of preparing a bulk amorphous metal article
US4762678A (en) * 1987-11-03 1988-08-09 Allied-Signal Inc. Method of preparing a bulk amorphous metal article
US4859413A (en) * 1987-12-04 1989-08-22 The Standard Oil Company Compositionally graded amorphous metal alloys and process for the synthesis of same
DE3741119A1 (de) * 1987-12-04 1989-06-15 Krupp Gmbh Erzeugung von sekundaerpulverteilchen mit nanokristalliner struktur und mit versiegelten oberflaechen
US4892579A (en) * 1988-04-21 1990-01-09 The Dow Chemical Company Process for preparing an amorphous alloy body from mixed crystalline elemental metal powders
US5026419A (en) * 1989-05-23 1991-06-25 Hitachi Metals, Ltd. Magnetically anisotropic hotworked magnet and method of producing same
US5112388A (en) * 1989-08-22 1992-05-12 Hydro-Quebec Process for making nanocrystalline metallic alloy powders by high energy mechanical alloying
US7560001B2 (en) * 2002-07-17 2009-07-14 Liquidmetal Technologies, Inc. Method of making dense composites of bulk-solidifying amorphous alloys and articles thereof
RU2533982C2 (ru) * 2009-04-30 2014-11-27 Шеврон Ю.Эс.Эй.Инк. Обработка поверхности аморфных покрытий
PL234845B1 (pl) * 2018-05-25 2020-04-30 Politechnika Czestochowska Amorficzny stop objętościowy

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Also Published As

Publication number Publication date
DE3669540D1 (de) 1990-04-19
DE3515167A1 (de) 1986-10-30
EP0200079A1 (fr) 1986-11-05
US4710236A (en) 1987-12-01
JPS61250122A (ja) 1986-11-07

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