Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B15/00—Layered products comprising a layer of metal
  • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
  • B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
  • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
  • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
  • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
  • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
  • H01F1/147—Alloys characterised by their composition
  • H01F1/153—Amorphous metallic alloys, e.g. glassy metals
  • H01F1/15383—Applying coatings thereon
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D7/00—Modifying the physical properties of iron or steel by deformation
  • C21D7/02—Modifying the physical properties of iron or steel by deformation by cold working
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
  • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
  • C21D8/1277—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties involving a particular surface treatment
  • C21D8/1283—Application of a separating or insulating coating
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
  • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
  • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
  • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
  • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
  • H01F1/147—Alloys characterised by their composition
  • H01F1/153—Amorphous metallic alloys, e.g. glassy metals
  • H01F1/15333—Amorphous metallic alloys, e.g. glassy metals containing nanocrystallites, e.g. obtained by annealing
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F27/00—Details of transformers or inductances, in general
  • H01F27/24—Magnetic cores
  • H01F27/245—Magnetic cores made from sheets, e.g. grain-oriented
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
  • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
  • H01F41/0206—Manufacturing of magnetic cores by mechanical means
  • H01F41/0213—Manufacturing of magnetic circuits made from strip(s) or ribbon(s)
  • H01F41/0226—Manufacturing of magnetic circuits made from strip(s) or ribbon(s) from amorphous ribbons
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B82—NANOTECHNOLOGY
  • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
  • B82Y25/00—Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D2201/00—Treatment for obtaining particular effects
  • C21D2201/03—Amorphous or microcrystalline structure
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D2251/00—Treating composite or clad material
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D2261/00—Machining or cutting being involved
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/02—Apparatus or processes for manufacturing printed circuits in which the conductive material is applied to the surface of the insulating support and is thereafter removed from such areas of the surface which are not intended for current conducting or shielding
  • H05K3/022—Processes for manufacturing precursors of printed circuits, i.e. copper-clad substrates

Definitions

• the invention relates to a method of treating a fragile metallic thin strip and to products obtained at the end of the strip treatment, which may include forming operations such as cutting.
• the method relates to obtaining by cutting from a metal strip with an ⁇ anocrystalline structure. parts for magnetic use.
• Nanocrystalline metallic materials are obtained, in the form of thin strips, for example with a thickness of the order of 20 ⁇ m, from amorphous strips or ribbons produced by casting and rapid cooling of a liquid metal on a cylinder or between two cooled cylinders.
• the amorphous bands or ribbons are heat treated by maintaining at a temperature of the order of 550 ° C. for a period of the order of one hour, so that they develop a na ⁇ ocristaliine structure, in a substantial part, for example greater than 50% of their volume. This heat treatment can be preceded by heat treatments prior to lower temperatures, for example of the order of 200 ° C.
• bands or ribbons having a nanocrystalline structure are of very great brittleness so that the slightest mechanical stress causes a rupture of the band or ribbon. It is not even possible to handle the tapes or ribbons of nanocrystalline structure without taking very large precautions, due to the fact that stresses, even very weak, induced in the strip lead to its fragile rupture.
• the only method currently known for manufacturing magnetic components such as magnetic cores, from strips with nanocrystalline structure consists in winding the strip of magnetic alloy in the amorphous state, then in heat treating this strip at the temperature at which the nanocrystalline structure develops. The heat treatment can optionally be carried out under a magnetic field to modify the hysteresis cycle of these nanocrystalline alloys. It is therefore not currently possible to manufacture nanocrystalline magnetic components by mechanical treatment or machining operations comprising, for example, cutting.
• the object of the invention is therefore to propose a method for treating at least one fragile metallic thin strip having a thickness of less than 0.1 mm, comprising at least one step in which the thin strip is subjected to stresses, this process making it possible to avoid risks of rupture of the fragile strip during its treatment and to obtain in particular parts of precise and / or complex geometric shape from the thin fragile strip.
• At least one face of the strip is covered with a coating layer comprising at least one polymeric material so as to obtain on the strip a adherent layer with a thickness between 1 and 100 ⁇ m, modifying the deformation and fracture properties of the metallic thin strip and the process step in which the strip is subjected to stresses is carried out on the strip covered with the coating layer.
• FIG. 1 is a schematic side elevation view of an installation for implementing the method according to the invention and according to a first embodiment.
• Figure 2 is a schematic side elevational view of an installation for implementing the method according to the invention and according to a second embodiment.
• Figures 3 and 4 are side elevational views of facilities for implementing two successive phases of a treatment method according to the invention and according to a third embodiment.
• FIG. 5 is a side elevation view of an installation allowing the implementation of the method according to the invention and according to a fourth embodiment.
• FIGS. 6A, 6B and 6C are perspective views of parts of transformers obtained by a method according to the invention comprising a step of cutting a thin nanocrystalline magnetic strip.
• FIGS. 7A, 7B and 7C are perspective views of toric magnetic cores obtained by a treatment method according to the invention comprising a cutting step.
• FIG. 8 is a perspective view of a component of an electrical circuit obtained by a treatment method according to the invention of nanocrystalline thin strips.
• Figures 9A, 9B, and 9C are schematic views showing three successive phases of the implementation of a treatment method according to the invention comprising a chemical cutting step.
• Figure 10 is a top view showing a set of parts obtained by a method according to the invention implementing a chemical cutting.
• Figures 11 A, 11 B, 11 C, 11 D and 11 E are schematic views showing the successive phases of the implementation of the method of the invention for the manufacture of a transformer integrated or not integrated into a printed circuit .
• the magnetic material is a soft magnetic material, generally consisting of an alloy containing mainly iron or, optionally, a mixture of iron and a ferromagnetic metal such as nickel and cobalt, as well as copper, silicon, boron and a metal such as niobium.
• the magnetic material could also contain iron, zirconia and boron and possibly copper and silicon.
• the magnetic alloys to which the invention applies are therefore for example Fe-Cu-Nb-B-Si or Fe-Zr- (Cu) -B- (Si) alloys (the brackets around the symbols Cu and Si indicating that these elements may possibly be absent).
• an iron-based alloy has been developed having the following atomic composition: Fe 73 , 5 Cui Nb 3 Si ⁇ 3 , s B 9 .
• the numbers given in index of the elements of the alloy correspond to the atomic percentages of these elements in the alloy.
• the iron alloy in the liquid state is poured onto a cylinder which is a good conductor of heat and is effectively cooled, so as to obtain strips or ribbons in the amorphous state with a thickness of the order of 20 ⁇ m and d '' a width greater than 5 mm.
• the bands or ribbons in an amorphous state are then subjected to an annealing heat treatment at a temperature in the region of 550 ° C.
• a structure with fine crystals or nanocrystalline structure in a large volume fraction of the strip, for example a structure made up, by volume, of at least 50% of grains of a size less than 100 ⁇ m.
• the treatment according to the invention is implemented in order to obtain, by cutting the strip, shaped magnetic pieces, avoiding a break in the metal strip during cutting.
• the treatment method according to the invention is generally implemented on the strip in the nanocrystalline state.
• the treatment according to the invention can be implemented on a strip in the amorphous state, a heat treatment then making it possible to develop the nanocrystalline structure.
• the strip wound in an amorphous state can be introduced into a heat treatment oven, so that a nanocrystalline strip wound on a mandrel is obtained, at the end of the heat treatment.
• This heat treatment can be carried out under a magnetic field.
• the treatment according to the invention consists firstly in covering one face of the strip of nanocrystalline alloy with a coating layer comprising a polymer.
• the strip covered on one of its faces by a layer of material containing a polymer can be handled without risk of breakage.
• the strip can then be covered on its second face by a layer of material containing a polymer and the two layers covering the strip are made adherent on the faces of the strip, by application of pressure and / or by a heat treatment. It is then possible to superimpose and assemble, for example by gluing, pressure or heat treatment, several metal strips covered on one or two faces by a layer containing a polymer, so as to obtain laminated composite products comprising several superimposed metal layers separated by layers containing a polymeric material.
• the treatment according to the invention comprises an additional operation, for example machining or forming the metal strip coated on its two faces or the laminated composite strip, to obtain shaped parts, for example by cutting the strip.
• the covering of a nanocrystalline strip 1 is carried out on a first and on a second face successively with an adhesive material consisting of a pre-glued plastic film.
• the nanocrystalline alloy strip 1 is wound on a mandrel 2 having a radius of curvature sufficient to avoid deformation or excessive stressing of the strip 1.
• the winding on the mandrel 2 was carried out on the cast strip and cooled in the amorphous state which was then heat treated at about 550 ° C. in the wound state on the mandrel.
• bonding on a first face of the strip 1 unwound from the mandrel 2 is carried out with a strip of pre-glued polymer material 3.
• the strip 3 of pre-glued polymeric material is unwound from a reel, then applied and pressed against the strip 1 of nanocrystalline alloy by a pressing roller in an arrangement opposite the reel constituted by the strip in nanocrystalline alloy 1 wound on the mandrel 2.
• the contacting and adhesion of the strip 3 is carried out on the upper face of the strip of nanocrystalline alloy 1, at the exact point where the strip 1 is unwound. This avoids any manipulation of a strip section 1 not covered with a layer of pre-glued plastic.
• the strip of nanocrystalline alloy 1 covered on its upper face by the strip of polymer material 3 is brought into contact, on its lower face, with a second strip of pre-glued polymer material 3 'wound in the form of a coil. .
• Two pressing rollers 4 and 4 'facing each other make it possible to exert pressure on the strip 1 covered by the strips 3 and 3' made of polymer material.
• the pressure exerted by the rollers pressing 4 and 4 ′ provides good adhesion of the strips 3 and 3 ′ on the faces of the strip of nanocrystalline alloy 1.
• the strip 1, joined to the covering layers 3 and 3 ′ constitutes a laminated strip 6 whose behavior at deformation and at break is fundamentally different from the behavior of the nanocrystalline alloy strip 1 which is essentially fragile.
• the laminated strip 6 no longer exhibits a fragile behavior and its rupture modes are radically different from the fragile rupture modes of the strip 1.
• the invention can be subjected to shearing such as that implemented in a mechanical cutting process of the strip. We can thus obtain by cutting the strip 6 shaped parts without risk of rupture of the strip 1 of nanocrystalline alloy which is fixed by its two faces to the covering strips of polymer material 3 and 3 '.
• the tapes with a nanocrystalline structure To obtain magnetic parts having satisfactory properties, it is necessary for the tapes with a nanocrystalline structure to have low internal stresses, these stresses being as low as possible.
• This can be achieved by heat treating amorphous strips on a mandrel or core with a large radius of curvature, as described above, or by using an oven for heat treatment of the non-wound strip and in an unstressed state. , for example in an oven allowing the treatment of the strip laid flat on a support.
• the operations carried out on the nanocrystalline strip covered with two adhesive layers of polymer practically do not create constraints in the nanocrystalline strip, even if these operations tions result in significant external stresses, such as shear stresses.
• the films of polymeric material 3 and 3 ′, pre-glued, which are used to cover the two faces of the strip 1, may consist of a film of a polymeric material such as polyester, polytetrafluoroethylene (PTFE) or a polyimide, the film being associated with a layer of self-adhesive material allowing the film to be glued onto the strip.
• Certain self-adhesive materials can be crosslinked inside a heat treatment installation such as installation 5 shown in FIG. 1. It is then possible to manufacture, from laminated strips 6 comprising a nanocrystalline strip covered on its two faces by strips of polymer material, a laminated composite material comprising several laminated strips 6 superimposed and made adherent to each other, by pressure and / or by heat treatment.
• such composites can be obtained from laminated strips 6 consisting of the nanocrystalline strip 1 covered on its two faces or on one side only by double-sided polymer strips, that is to say strips having self-adhesive layers. -adhesive on both sides.
• any magnetic part for example in the form of U or in E shape, or any complex shaped magnetic part used in watchmaking, as will be explained below.
• the layers of polymer material used to cover the nanocrystalline strip are chosen so as to avoid degrading the magnetic characteristics of the nanocrystalline strips by the stresses induced during the adhesion of the polymer strip to the nanocrystalline strip or during the crosslinking operation of polymers in contact with the nanocrystalline strip.
• the strip should not be placed under strong tension or compression stress during the adhesion or crosslinking phase.
• the magnetic components obtained by the process of the invention must be able to withstand a relatively high temperature, for example at a temperature of 150 ° vs.
• the polymers constituting the covering layers of the nanocrystalline strip which remain fixed on the magnetic parts obtained after cutting, must withstand the temperature of use of the magnetic parts.
• a hot-melt polymer film which only becomes adhesive during a heat treatment.
• Such a hot-melt film is said to be “non-tacky”, because its hot-melt part is not adhesive at ambient temperature.
• FIG. 2 there is shown a phase of a treatment according to the invention, during which a cutable composite is formed consisting of nanocrystalline strips and covering layers of polymeric material bonded together by a material which is hot-meltable. 'resulting from a heat treatment.
• nanocrystalline alloy strips are used which are generally wound in the form of coils and which are obtained by treatment of an alloy coil in the amorphous state.
• Each of the nanocrystalline alloy strips used for the manufacture of the composite is covered, on its upper face and on its lower face, by a pre-glued hot-melt polymer film.
• the bands 7a, 7b and 7c are brought to pass inside a heating enclosure 8 at a temperature below 400 ° C. which makes it possible to bring the temperature of the hot-melt films of the covering layers of the laminated strips 7a, 7b, 7c above.
• the strips 7a, 7b and 7c are bonded between two pressing rollers 9a and 9b. After cooling in a cooling enclosure 10, a composite strip 11 is obtained which can be cut in the form of shaped magnetic pieces.
• thermofusible films allowing the adhesion of the covering layers may consist of one of the following polymers: modified polyethylene (by acrylic acid, maleic anhydride or others), grafted polypropylene, polyamide, polyurethane.
• the properties of the laminated composite 11 obtained by the process used according to the second embodiment allow cutting without breaking and without forming undesirable stresses in the strips of nanocrystalline material.
• laminates or composites according to the invention can be produced by a process of coating or sizing the faces of one or more nanocrystalline strips.
• a non-tacky reactivatable adhesive material with a thickness of between 1 and 50 microns is then used.
• An adhesive is said to be reactivable or bistable when it is possible to carry out on this adhesive two successive polymerizations or reticulatio ⁇ s. Such a material is said to be non-tacky because it does not stick after the first crosslinking.
• This adhesive can be chosen from thermosetting or thermoplastic polymers, depending on the magnetic performance sought for the magnetic component to be produced from the laminate or composite. These magnetic performances may indeed depend on the thermal conditions imposed on the laminate or the composite, during its manufacture.
• Figure 3 there is shown schematically an installation for manufacturing a laminated material comprising a nanocrystalline strip by a process of direct coating of the faces of the nanocrystalline strip using a reactivatable adhesive.
• the nanocrystalline strip 1 which preferably comes from a coil, is deposited on a support strip 12 preferably formed in the form of a flexible flexible strip, in the direction indicated by the arrow 12 '.
• a first coating installation 14a and a first drying and crosslinking installation 15a inside which the strip of nanocrystalline alloy 1 supported by the support strip 12 is moved in the direction of the arrow 12 '.
• a coating layer 13 is deposited on the upper face of the nanocrystalline strip 1 inside the first induction installation 14a. This coating layer 13 is dried and crosslinked inside the first drying and crosslinking installation 15a.
• the strip of nanocrystalline alloy 1, coated with the plastic layer 13 which is adherent on its upper face, can be handled without risk of breakage. It is then possible to pass the strip 1 coated with the coating layer 13 of the support strip 12 into a second coating installation 14b ensuring deposition on the second face, or lower face of the strip 1, d 'a second coating layer 13' which is dried and crosslinked in a second drying and crosslinking installation 15b in which the strip coated on its two faces is brought to pass. There is obtained, at the outlet of the installation shown in FIG. 3, a laminated strip 16 comprising the central nanocrystalline strip 1 coated on its two faces with coating layers of crosslinked polymer material 13 and 13 ′.
• the nanocrystalline strip coated on both sides with perfectly adhesive layers of plastic, no longer exhibits fragile behavior and can be cut in the form of magnetic pieces of complex shapes.
• a laminated composite strip could also be obtained by stacking strips of nanocrystalline alloy covered on one side.
• the strips 16a, 16b and 16c can be passed through a heating enclosure 18 allowing them to be brought to a temperature below 400 ° C.
• the heated strips 16a, 16b and 16c are then pressed between two pressing rollers 19a and 19b, which makes it possible to obtain bonding one on the other of the strips 16a, 16b and 16c which comprise hot-melt polymers.
• the composite strip 17 obtained is cooled in a cooling installation 20.
• a subsequent step of the treatment process according to the invention it is possible to produce, by cutting out the composite strip 17, magnetic parts without breaking the nanocrystalline strips constituting the composite 17.
• the first step consisting in producing the laminate 16 by depositing polymer layers on one or both sides of a nanocrystalline strip can be produced not only by coating, as indicated above, but also by spraying a polymeric covering product on one of the faces or each of the faces of the strip, successively. The covering product is then polymerized. It would also be possible to deposit on the two faces of the nanocrystalline strip in a single step by dipping. However, handling the nanocrystalline bands would then be more delicate.
• a polymer of one of the following types acrylic material, polyester, epoxy resin, phenolic epoxy resin, polyester / epoxy resin, phenolic resin with modifier, polyurethane resin / polyester.
• the covering layer of polymer material can have a thickness of 1 to 50 ⁇ m.
• the treatment method according to the invention which comprises a step of producing a covering layer of nanocrystalline bands can be associated with the prior method of producing nanocrystalline bands from amorphous bands.
• FIG. 5 shows an installation making it possible to carry out the first step of covering with a layer of polymeric material of the treatment according to the invention on nanocrystalline strips at the outlet of the heat treatment oven making it possible to develop nanocrystalline structures in bands of amorphous alloy.
• a heat treatment oven 22 in an inclined arrangement which can be constituted for example by a quartz tube surrounded by electric heating means as well as an inductor allowing to optionally subject the strip to a field magnetic.
• Several amorphous bands are passed inside the furnace 22, for example three bands of amorphous alloy 21 a, 21 b and 21 c.
• the amorphous bands 21a, 21b and 21c are subjected to a heat treatment at a temperature close to 550 ° C. inside the furnace 22, for a time sufficient to develop a nanocrystalline structure in these bands.
• the strips 21 a, 21 b and 21 c are cooled in a cooling installation 23 and then deposited on a movable support strip 24.
• the strips are then covered, on one or on both sides, with self-adhesive pre-glued polymer strips. , wound in the form of coils such as 24a and 25a placed on the path of each of the bands such as the band 21a.
• three laminated strips constituted by a strip of nanocrystalline alloy covered on one or on its two faces by strips of adhesive polymer material.
• the laminated strips obtained can be cut in the form of magnetic pieces or assembled by gluing to form composite strips comprising several superimposed laminated strips which can themselves be cut.
• FIGS. 6A, 6B and 6C examples of parts have been shown produced by cutting strips of laminated composite material constituted by superposition and solidahsation of laminated strips each consisting of a nanocrystalline strip covered with one or two layers of polymeric material adhering to the faces of the nanocrystalline strip.
• the laminated composite material can consist of a plurality of superimposed laminated strips and linked to each other, this number of superposed strips possibly being for example equal to three or more.
• a stack of three superimposed laminated strips has a thickness of 80 ⁇ m, ie 0.08 mm. It is of course possible to produce magnetic parts by cutting thicker laminated composite strips, for example with a thickness of 1 mm or more.
• transformer parts in the form of E, I or U it is possible to produce transformer parts in the form of E, I or U, as it is visible respectively in FIGS. 6A, 6B and 6C respectively showing a transformer part 26a in the form of E, a transformer part
• Such transformer parts have very good magnetic properties, because they consist of nanocrystalline alloy layers and very good mechanical properties, because the nanocrystalline alloy sheets are protected by plastic layers adherent over their entire surface. Additionally, as noted above, during the cutting of the laminated composite products, the risk of rupture of the nanocrystalline bands is extremely reduced.
• the cutting of parts as shown in FIGS. 6A, 6B and 6C can be carried out by any method of mechanical cutting of shaped parts, for example by punching.
• the laminated structure of the parts obtained is also favorable for limiting the losses by eddy currents in these parts, when they are used as parts of transformers.
• toroids can be produced in the form of cut-out washers 27a, as shown in FIG. 7A, or in the form of frames with a square or rectangular section 27b, hollowed out in their center, as shown in Figure 7B.
• toroids with an air gap having the form of laminated washers 27c comprising a radial slot 27'c constituting an air gap. Both the cutting of the washers 27c and the production of the slot 27'c can be carried out without risk of breaking the nanocrystalline strips constituting the laminated composite product. We thus obtain cut toroids which can be very small.
• the parts obtained as shown in FIGS. 6A to 6C and 7A to 7C can be parts of small or very small dimensions which also have a flat shape and a very small thickness.
• the method according to the invention can also be used to produce anti-theft labels made of high permeability material, the presence of which on an article or object can be identified during the passage of the object in a loop of a circuit traversed by a current.
• the passage of the object carrying the anti-theft label is then detected by the variation of the current induced in the loop.
• inductors or thin transformers 28 having a thickness which can be, for example, of the order of one millimeter, allowing the mounting of these inductors or thin transformers, against a surface of a device.
• a laminated composite strip comprising superposed laminated layers each consisting of a nanocrystalline strip surrounded by layers of polymeric material are cut, for example in the form of rectangles 28 in which openings are formed, for example of square section. From the part obtained, the primary and secondary parts of a transformer can be made by winding electrical wires 28 '.
• the magnetic parts are cut out from the laminated or composite laminated strips by a mechanical process. As shown in FIGS. 9A to 9C and 10, it is also possible to produce magnetic pieces of complex shape from thin strips of nanocrystalline alloy, by a chemical cutting process.
• a laminate 29 is first produced from a strip of nanocrystalline alloy 30 which is coated on one of its faces by a strip of polymer material 31 which is bonded with the strip 30 by a method as described above.
• the laminated strip 29 is then covered with a layer 32 of a photosensitive resin and, through a screen 33 of suitable shape, the resin layer is exposed by rays of light 34 photosensitive 32 deposited on the outer surface of the strip of nanocrystalline alloy of the laminate 29.
• a suitable solvent for example, the solvent used can be water in the case where the photosensitive layer consists of modified casein.
• FIGS. 11A to 11 E it is possible, as shown in FIGS. 11A to 11 E, to fabricate a transformer integrated into a printed circuit or a discrete transformer, by a method according to the invention.
• a laminate 36 (FIG. 11A) is produced, consisting of a strip of nanocrystalline alloy 36a and a film of polymeric material 36b adhering to one of the faces of the strip 36a.
• a product 38 comprising the plastic film 36b as a substrate and successive thin magnetic circuits 37 of nanocrystalline alloy, for example in shape of rectangular frames, adhering to the substrate ( Figure 11 B).
• the product 38 is cut into sections, each comprising a thin magnetic circuit 37 fixed to a section of substrate.
• the cut sections (39 (FIG. 11 C)) are stacked one on top of the other so that the magnetic circuits 37 are exactly superimposed and separated by the layers of plastic substrate 36b. on the other, superimposed layers 36b, for example by heating and pressing, to obtain a composite laminate product 40 (FIG. 11 D).
• the films of plastic material are pierced, as shown in FIG. 11 D. that superimposed 36b, in zones located inside and outside the superimposed magnetic circuits 37, to obtain a plurality of openings 41 passing through the composite laminate 40.
• the openings 41 are then metallized internally, so as to create continuous conductive zones between the two faces of the composite laminate 40 onto which the openings 41 open.
• electrical conductors such as 42 and 43 joining the ends of a first set of openings 41 on each of the faces of the laminate are produced (FIG. 11E), on the two faces of the composite laminate 40, for example by chemical etching. composite 40 and a second set of openings 41, respectively.
• the conductors 42 and 43 and the metallized openings 41 to which they are connected constitute the primary and secondary windings of the transformer 44 which can be used in a printed circuit.
• it would also be possible to produce other components such as inductors intended to be inserted in a printed circuit or inserted on a printed circuit and comprising at least one winding.
• the covering of one or both sides of strips of nanocrystalline alloy is carried out, that is to say of strips obtained after a heat treatment of an amorphous strip to obtain a nanocrystalline strip.
• a coating is produced on one or both sides of an amorphous strip, with a complex mixture of solvents which may consist of water, polymeric binders, aluminates, silicates and fluxes.
• a first baking of the inorganic adhesive is carried out in order to obtain an amorphous strip / cutable inorganic adhesive composite.
• the cut pieces are heat treated at a temperature allowing the germination of the nanocrystals in the amorphous strip and vitrification of the mixture of powders, aluminate, silicate and flux.
• a temperature above 500 ° C may be suitable depending on the type of polymer, silicate, aluminate and flux mixture used.
• the polymer is oxidized during the heat treatment.
• the following substances can be used to form the coating mixture for the amorphous strip, this mixture being in a pasty state:
• Solvents for example a mixture of aliphatic or aromatic hydrocarbons which are intended to dissolve the resin and which must be easily removed by treatment at low temperature, for example at 100 ° C;
• a mineral filler for example glasses or oxides, intended to reinforce the adhesion of the layer to the material in the nanocrystalline state, after its treatment;
• An organic filler for example consisting of organo-metallic or surface-active substances, intended to improve the dispersion, wetting and the corrosion resistance of the covering layer.
• composition of the pasty coating substance is given below: metallic filler: 40 to 70 parts by volume resin: 3 to 10 parts by volume mineral filler: 3 to 6 parts by volume organic fillers: 0.5 2 parts per solvent volume: the rest of the composition, up to 100 volume parts.
• metallic filler 40 to 70 parts by volume resin: 3 to 10 parts by volume mineral filler: 3 to 6 parts by volume organic fillers: 0.5 2 parts per solvent volume: the rest of the composition, up to 100 volume parts.
• the method according to the invention makes it possible to obtain magnetic parts of complex shapes made of nanocrystalline alloy, which was not possible until now, the only parts of nanocrystalline alloy which can be obtained being toric cores constituted by a strip rolled up.
• these bands can be manipulated and implemented in various ways and for example split in the form of bands having a width less than the width of the nanocrystalline band cast in amorphous form and treated thermally.
• the method according to the invention makes it possible to avoid the risks of rupture of the thin strips of nanocrystalline alloy or possibly of amorphous alloy, during the forming of the magnetic parts, for example by cutting or drilling.
• the invention which finds a particularly advantageous application in the case of nanocrystalline alloys, can however be used in all cases where it is necessary to manipulate or to shape thin, fragile metal strips having a thickness of less than 0, 1 mm.
• the invention is also not limited to the embodiments which have been described above.
• the invention is also not limited to the nature and composition of the layers produced on the thin metal strips, during the first phase of the process according to the invention.
• the invention is also not limited to the case where the strips are cut in a second step of the process, but applies to all cases where manipulation or machining is carried out on fragile thin metal strips. , this manipulation or machining resulting in the stressing of the fragile strip.
• the invention can be applied in different fields of the manufacture of magnetic parts.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Power Engineering (AREA)
• Physics & Mathematics (AREA)
• Crystallography & Structural Chemistry (AREA)
• Materials Engineering (AREA)
• Electromagnetism (AREA)
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• Organic Chemistry (AREA)
• Metallurgy (AREA)
• Dispersion Chemistry (AREA)
• Mechanical Engineering (AREA)
• Inorganic Chemistry (AREA)
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• Soft Magnetic Materials (AREA)
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• Hard Magnetic Materials (AREA)

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• 1999
  • 1999-01-19 FR FR9900521A patent/FR2788455B1/fr not_active Expired - Fee Related
• 2000
  • 2000-01-14 ES ES03027268T patent/ES2256651T3/es not_active Expired - Lifetime
  • 2000-01-14 ID IDW00200101572A patent/ID29815A/id unknown
  • 2000-01-14 BR BR0007607-4A patent/BR0007607A/pt not_active Application Discontinuation
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  • 2000-01-14 AU AU30547/00A patent/AU3054700A/en not_active Abandoned
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  • 2000-01-14 EP EP00900585A patent/EP1147234B1/fr not_active Expired - Lifetime
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  • 2000-01-14 EP EP03027268A patent/EP1413632B1/fr not_active Revoked
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  • 2000-01-14 CA CA002358907A patent/CA2358907A1/fr not_active Abandoned
  • 2000-01-14 KR KR1020017008997A patent/KR20010109279A/ko not_active Withdrawn
  • 2000-01-14 DE DE60013402T patent/DE60013402T2/de not_active Expired - Lifetime
  • 2000-01-14 JP JP2000594962A patent/JP3822440B2/ja not_active Expired - Fee Related
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• 2006
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