CN1162184A

CN1162184A - Magnetic core of pulse transformer

Info

Publication number: CN1162184A
Application number: CN97100612A
Authority: CN
Inventors: 内藤丰; 半谷胜章; 畑内隆史; 牧野彰宏; 和田真治郎; 齐藤雄一; 井上明久; 增本健
Original assignee: Alps Electric Co Ltd; Japan Science and Technology Corp
Current assignee: Japan Science and Technology Agency; Alps Alpine Co Ltd
Priority date: 1996-03-06
Filing date: 1997-03-06
Publication date: 1997-10-15
Anticipated expiration: 2017-03-06
Also published as: EP0794541A1; DE69714103T2; KR970067403A; CN1069145C; KR100222442B1; DE69714103D1; JPH09246034A; EP0794541B1

Abstract

A pulse transformer magnetic core comprising a magnetic core main body of a soft magnetic alloy ribbon having a thickness of 25 mu m or less, the AL value of the magnetic core main body being 4.0 mu H/N<2> or more when 0.1 V is input at 10 kHz. The magnetic core main body has an outer diameter of 10 mm or less and a thickness of 1.2 mm or less. The magnetic core main body may comprises by coiling the soft magnetic alloy ribbon or by stacking rings or E-shape and I-shape pieces which are made from the soft magnetic alloy ribbon by a punching process.

Description

Magnetic core of pulse transformer

The present invention relates to a kind of magnetic core of pulse transformer with superior impedance frequency characteristic and superior pulse transmission characteristic.

Recently, the development trend of electronic device field is to make every effort to reach microminiaturization, slimming and high-performance.Specifically, the pulse transformer that is used for the interface of ISDN (integrated services digital network network) etc. must satisfy the electrical characteristic by some strict standards (for example I.430 the ITU-T suggestion waits) defined.According to a kind of like this electrical characteristic of standard code, the desired impedance of elementary winding of pulse transformer should be 1,250 Europe (Ω) at least, and should be 2,500 Europe (Ω) at least when 100 kilo hertzs (kHz) when 10 kilo hertzs (kHz).These impedances are 20 milihenries (mH) and 40 milihenries (mH) corresponding to inductance respectively.The voltage pulse output waveform must be in pulse shielding (pulse mask) scope of above-mentioned standard code.In addition, wish that the inductance characteristic of elementary winding is preferably smooth as far as possible.

In order to assemble PC card etc., be starved of the microminiaturization of pulse transformer.For example, when on the inner panel that a pulse transformer is encapsulated in a pcmcia card (a kind of Interface Standard card of notebook personal computer), because the thickness of this card itself is approximately 5 millimeters (mm), therefore, the height of pulse transformer must be not more than 3 millimeters (mm).In this case, the area of general encapsulation must be 14.0 millimeters (mm) * 14.0 millimeter (mm) or littler.

At present, in this case, mainly use the core material of the ferrite of high permeability as the pulse transformer of ISDN.Pulse transformer has the magnetic core of EI-or EE-shape, and the butting surface of magnetic core is through mirror finish.EI-shape magnetic core be core material with the core material of E-shape and I-shape by docking in aggregates making, lead then is wrapped on the E-shape core material, thereby constitutes a transformer.EE-shape magnetic core docks in aggregates making each other with the magnetic core of two E-shapes.

Though the generally acknowledged value of the ferritic initial magnetic permeability of high permeability of magnetic core that is used for the pulse transformer of ISDN is 10,000 to 12,000,, ferritic initial magnetic permeability varies with temperature and acute variation.In the time of-20 ℃, the value of ferritic initial magnetic permeability is than its generally acknowledged value about low 40%.Therefore, in the time must guaranteeing that this pulse transformer is worked in-40 ℃ to 100 ℃ temperature range, when the transformer of FERRITE CORE was used in design, essential consideration was than the initial magnetic permeability value of generally acknowledging that value reduces greatly.

In order to make pulse transformer reach the desired inductance of ISDN, the effective cross section of the magnetic core number of turn long-pending or coil must increase.Yet in the pulse transformer of common structure, because the increase of coil turn, the part (for example starting point of winding and terminal point) that has different voltages in the winding around is approaching mutually inevitably, therefore causes leakage inductance and parasitic capacitance to increase.Like this, the transmitted frequency field of transformer narrows down, and the fidelity that waveform transmits reduces.On the other hand, the long-pending increase in magnetic core effective cross section and the microminiaturization of pulse transformer itself are inconsistent.Therefore, be difficult to produce that to have highly be 3 millimeters (mm) or littler, and the pulse transformer with FERRITE CORE of superior transmission characteristic, and this superior transmission characteristic but will meet the requirement of ISDN in the limited field of above-mentioned pulse transformer package area.

Some pulse transformer can satisfy desired characteristic by using thin FERRITE CORE and coil turn being increased to 100 or more on minimum degree.Yet when coil turn is decreased to less than 100 the time, this pulse transformer just can not satisfy desired characteristic.

An object of the present invention is to provide a kind of height is 3 millimeters (mm) or littler, and the less pulse transformer of coil turn, and this transformer has superior frequency-impedance operator and superior transmission characteristic in big range of temperature.

Another object of the present invention is to provide a kind of magnetic core cross-sectional area to increase, and the pulse transformer that its stress is suppressed by resinous coat.

Magnetic core of pulse transformer according to the present invention comprises that one is the magnetic core main body that 25 microns (μ m) or littler magnetically soft alloy band are made by thickness.(v) during voltage, under 10 kilo hertzs (kHz), the AL value of this magnetic core main body is 4.0 microhenrys/newton when 0.1 volt of input ²(μ H/N ²) or bigger.

This magnetic core main body can comprise a plurality of lamination annulus.These lamination annulus are made by the magnetically soft alloy band, and its external diameter is 10 millimeters (mm) or littler, and its thickness is 1.2 millimeters (mm) or littler.

This magnetic core main body can comprise an E-shape magnetic core and an I-shape magnetic core, any compound mode of U-shape magnetic core and an I-shape magnetic core and two U-shape magnetic cores, wherein, this E-shape magnetic core, this I-shape magnetic core and this U-shape magnetic core are respectively the E-shape thin slice of being made by the magnetically soft alloy band, I-shape thin slice and U-shape thin slice are piled up and are constituted, and the thickness of this magnetic core main body is 1.2 millimeters (mm) or littler.

This magnetic core main body can comprise a toroidal annulus, and it is by being that 1.2 millimeters (mm) or littler magnetically soft alloy band coiled dish type constitute with width, and the external diameter of this toroidal core main body is 10 millimeters (mm) or littler.

This toroidal annulus preferably is encapsulated in the lid that is formed from a resin, and its encapsulation rate is 50% or more.

The magnetostrictive absolute value of this magnetically soft alloy band is preferably 1 * 10 ^-6Or it is littler.

In-40 ℃ to 100 ℃ temperature range, the AL value of this magnetic core of pulse transformer can be in ± 20% to the bias of the AL value under the room temperature.

The most handy silicone rubber dipping of this magnetic core main body.Viscosity before this silicone rubber solidifies is 1 handkerchief second (PaS) or littler, and by solidification, silicone rubber can be got up by gelling.

This magnetic core main body also before the most handy curing viscosity be 1.5 handkerchiefs second (PaS) or littler, and JISA hardness is 10 or littler silicone rubber dipping.This silicone rubber plays the effect that this magnetic core main body is fixed on the bonding agent on the magnetic core housing.

With the magnetic core main body be fixed on bonding agent on the magnetic core housing be preferably solidify before viscosity be 2 handkerchiefs second (PaS) or littler, and the JISA hardness after solidifying is 25 or littler silicone rubber.

This bonding agent preferably is coated on two to four parts on this magnetic core housing bottom surface.

The characteristics of this magnetically soft alloy are, 50% or more magnetically soft alloy constitute by many body-centered cubic fine grains basically, the average-size of crystal grain is 30 nanometers (nm) or littler.This magnetically soft alloy comprises iron (Fe) as Main Ingredients and Appearance, and in addition, having an element at least is to select from the element set of being made up of Ti (titanium), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), molybdenum (Mo), tungsten (W) and boron (B).

The magnetic core of pulse transformer according to a second aspect of the invention comprises: a magnetic core main body and the magnetic core housing with opening of fixing this magnetic core main body that is made of the magnetically soft alloy band of coiled annular.

The two ends of the inner and outer wall of this magnetic core housing preferably have 0.05 millimeter (mm) radius of curvature to 0.4 millimeter (mm).

This magnetic core main body preferably with 50% or bigger encapsulation rate (packing rate) be encapsulated in this magnetic core housing.

The external diameter of this magnetic core housing can be 10 millimeters (mm) or littler, and internal diameter is 3.5 millimeters (mm) or bigger, highly is 1.3 millimeters (mm) or littler.And when at 0.1 volt of (V) voltage of input, its AL value under 10 kilo hertzs (kHz) is 6.0 microhenrys/newton ²(μ H/N ²) or bigger.

Fig. 1 is the installation diagram of a transformer, and this transformer has according to magnetic core of the present invention, that comprise a plurality of lamination annulus that are stamped to form by the magnetically soft alloy band;

Fig. 2 is the installation diagram of a transformer, and this transformer has according to magnetic core of the present invention, that formed by the magnetically soft alloy tape wrapping;

Fig. 3 is the installation diagram according to the magnetic core of pulse transformer of the present invention;

The cross-sectional view of Fig. 4 for being got along the A-A line of magnetic core container shown in Figure 3;

Fig. 5 has Fe for working as ₈₆Nb _3.25Zr _3.25B _6.5Cu ₁When the magnetically soft alloy annulus of composition is encapsulated in the housing, the figure of the dependency relation between encapsulation rate and the impedance;

Fig. 6 is for representing when having Fe ₈₆Nb _3.25Zr _3.25B _6.5Cu ₁When the magnetically soft alloy annulus of composition is encapsulated in the housing, the figure of the dependency relation between permeability and the impedance;

Fig. 7 is for being illustrated under 10 kilo hertzs (kHz) and 100 kilo hertzs (kHz), and the AL value is with respect to the variation figure of magnetically soft alloy annulus thickness;

Fig. 8 ought have Fe respectively for expression ₈₆Nb _3.25Zr _3.25B _6.5Cu ₁, Fe ₈₄Nb _3.5Zr _3.5B ₈Cu ₁And Fe _73.5Si _13.5B ₉Nb ₃Cu ₁When each magnetically soft alloy annulus of composition is encapsulated in the housing, the dependency relation figure between encapsulation rate and the impedance;

Fig. 9 is the permeability of each sample described in the presentation graphs 8 and the dependency relation figure between the encapsulation rate;

Figure 10 is the AL value of presentation graphs 8 described each sample and the dependency relation figure between the encapsulation rate;

Figure 11 is the permeability variation of each sample described in the presentation graphs 8 and Ferrite Material and the dependency relation figure between the temperature;

Figure 12 is the AL value temperature variant figure of expression according to sample of the present invention and comparative sample;

Figure 13 is the schematic diagram of an embodiment of alloy band process units;

Figure 14 comprises the DSC thermogram according to sample of the present invention and comparative sample;

Figure 15 is expression permeability and the dependency relation figure between the retention time;

Figure 16 is for the expression coercive force and between the retention time and saturation magnetostriction and the dependency relation figure between the retention time;

Figure 17 is expression crystallite dimension and the dependency relation figure between the retention time;

Figure 18 is the dependency relation figure between expression permeability and the maintenance temperature;

Figure 19 is expression permeability and the dependency relation figure between the retention time;

Referring now to embodiment and accompanying drawing the present invention is described.

For example, the core shapes according to pulse transformer of the present invention is an annular.This toroidal cores of pulse transformer is by the magnetically soft alloy band with following described composition is carried out Quenching Treatment, this alloy band punching press is made annulus, the annulus that will be predetermined quantity then pile up to constitute, or by this magnetically soft alloy roll coil of strip coiled toroidal is constituted.The magnetic core that forms is coated with one deck, for example, and epoxy resin or be encapsulated in the resinous housing, in case insulation, and then twine lead, obtain the magnetic core of pulse transformer.

EI-shape magnetic core is made as follows: by punching press, process the thin slice of many E-shapes and the thin slice of I-shape with above-mentioned magnetically soft alloy band, respectively each E-shape thin slice and I-shape sheet stacking are got up to constitute E-shape magnetic core and I-shape magnetic core then, again with E-shape magnetic core and the butt joint of I-shape magnetic core.Another kind method is, in utilizing resinous coat or the resin system of being encapsulated in housing, each given E-shape magnetic core and I-shape magnetic core partly insulated and finishes after the coiling lead, with the side butt joint of this E-shape magnetic core and I-shape magnetic core.The combination of magnetic core is not limited only to E-shape magnetic core and I-shape magnetic core.For example, such as two E-shape magnetic cores, any compound mode of U-shape magnetic core and an I-shape magnetic core and two U-shape magnetic core one classes all can be used as the magnetic core of this pulse transformer.

Fig. 1 and 2 represents the embodiment of annular transformer.In Fig. 1, this annular converter comprises lower house 2 and magnetic core main body 3 that is made of the annulus of many magnetically soft alloy band systems of 1, one circle of upper shell of a circle.These alloy band annulus are stacked in upper shell 1 and the lower house 2.In Fig. 2, this annular transformer comprises the lower house 2 of 1, one circle of upper shell of a circle and the magnetic core main body of being made by magnetically soft alloy band 53.This alloy band 5 is the coiled disc in this upper shell 1 and lower house 2, and uses resin-coating.This upper shell and lower house are not always will use, and like this, this magnetic core just is coated with one deck resinous coat.

Fig. 3 represents another embodiment of the magnetic core of this pulse transformer, and the cross-sectional view of Fig. 4 for being got along the A-A line of the magnetic core housing 7 of Fig. 3.This pulse transformer be shaped as annular, and comprise a circular shell 7 and a magnetic core main body 3 that has the cavity, center.And magnetic core main body 3 is to be wound into annular and to constitute by being placed on magnetically soft alloy band 5 in this circular shell 7.An opening 7a is arranged at the top of this magnetic core housing 7, and it need not cover etc. and to cover.This do not have the volume of magnetic core housing 7 of lid bigger for the size of whole magnetic core of pulse transformer.Therefore, this pulse transformer and shown in Figure 1 comprises that the pulse transformer of upper shell 1 and lower house 2 compares, owing to increased the cross-sectional area of magnetic core main body 3, inductance is improved, and the size of whole pulse transformer need not change.Another kind of way is, when the identical magnetic core main body 3 of the cross-sectional area that uses cross-sectional area and magnetic core main body shown in Figure 1, this magnetic core of pulse transformer can microminiaturization.

This magnetic core housing 7 does not have inner and outer wall.The top 7b of inwall and the top 7d of bottom 7c and outer wall and bottom 7e have 0.05 millimeter (mm) radius of curvature to 0.4 millimeter (mm).When radius of curvature during less than 0.05 millimeter (mm), then the coating of winding around 9 may be damaged, perhaps when the time around magnetic core housing 7 coiling coils 9, and top and bottom 7b, 7c, 7d and 7e may cut this coil.On the other hand, radius of curvature surpasses the thickness increase that 0.4 millimeter (mm) can make this magnetic core housing 7.As a result, the cross-sectional area of this magnetic core main body 3 and AL value reduce.

This magnetic core housing 7 is preferably by synthetic resin, and for example aldehyde resin or polyethylene terephthalate resin are made.

For magnetic core main body 3 is fixed on the magnetic core housing 7, on two positions of the bottom of this magnetic core housing 7 7f, coat bonding agent 4.In order to firmly fix magnetic core main body 3, must be coated with bonding agent 4 in two positions of bottom 7f at least, and excessive bonding agent can make the AL value reduce.Therefore, be preferably on 2 to 4 positions and be coated with bonding agent 4.Preferred bonding agent example is that viscosity is 2 handkerchiefs second (PaS) or littler before solidifying, and is 25 or littler silicone rubber and solidify back JISA hardness.When the viscosity of solidifying front attachment agent 4 was higher than this limiting value, this magnetic core main body 3 may be drawn together from the bottom of magnetic core housing 7, and highlights from this magnetic core housing 7.When the hardness of bonding agent 4 was higher than this limiting value when cured, because the influence of bonding agent shrinkage stress, the AL value reduced.Therefore, be preferably in the amount that reduces bonding agent 4 in the scope that magnetic core main body 3 can be fixed on the magnetic core housing 7, as much as possible.

In this embodiment, magnetic core main body 3 is made as follows: the magnetically soft alloy band 5 with following composition is wound into toroidal through Quenching Treatment, and the most handy then silicone rubber dipping then is cured.

By increasing the height of magnetic core main body 3, can improve the inductance of this pulse transformer.Yet, when the excessive height of this magnetic core main body 3, with the coiling coil 9 of the last end in contact of this magnetic core main body 3, because the rubbing action of this coiling coil 9 and may damaging.Therefore, preferably make the height low 0～0.05 millimeter (mm) of these magnetic core housing 7 inside of aspect ratio of this magnetic core main body 3.Be preferably in the scope that magnetic core main body 3 can be placed in the magnetic core housing 7, make the external diameter of this magnetic core main body 3 big as far as possible, and its internal diameter be as far as possible little.

Preferably making the viscosity before the silicone rubber that is immersed in the magnetic core main body 3 solidifies is 1 handkerchief second (PaS) or littler, and can gelling get up by curing.When the viscosity of silicone rubber was higher than this limiting value before solidifying, silicone rubber was immersed between each winding layer of magnetic core main body 3 hardly.When curing made the hardness of silicone rubber too high, because the distortion of silicone rubber, AL value can reduction.

Being immersed in silicone rubber in the magnetic core main body 3 also can be used as the bonding agent that this magnetic core main body 3 is fixed on this magnetic core housing 7 and uses.In this case, viscosity is 1.5 handkerchiefs second (PaS) or littler before preferably use solidifying, and is 10 or littler silicone rubber and solidify back JISA hardness.

Magnetic core main body 3 can not comprise silicone rubber.Yet an amount of silicone rubber that is immersed in the magnetic core main body 3 can be restrained the stress influence that produces and add the AL value reduction that thermal impact causes when being fixed on magnetic core main body 3 on the magnetic core housing 7.

In this embodiment, the magnetic core main body 3 of annular is formed by coiling magnetically soft alloy band.Also the magnetically soft alloy band can be struck out many annulus, the annulus with given number piles up then, forms magnetic core main body 3.

The shape of this magnetic core main body 3 can be EI shape.The magnetic core main body of EI-shape is made as follows: by punching press, process many E-shape thin slices and I-shape thin slice from the magnetically soft alloy band, respectively each E-shape thin slice and I-shape sheet stacking are got up to form an E-shape magnetic core and an I-shape magnetic core then, again with this E-shape magnetic core and the butt joint of this I-shape magnetic core.This magnetic core main body is placed in the magnetic core housing that has open end face, has just constituted the magnetic core of pulse converter.The combination of magnetic core is not limited only to E-shape magnetic core and I-shape magnetic core.For example, can adopt such as two E-shape magnetic cores any compound mode of U-shape magnetic core and an I-shape magnetic core and two U-shape magnetic core one classes for the magnetic core main body.

The most preferred magnetically soft alloy that is used for above-mentioned magnetically soft alloy band with iron (Fe) as its Main Ingredients and Appearance, and having an element at least is to select from the element set of being made up of titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), molybdenum (Mo), tungsten (W) and boron (B), and its microstructure has a large amount of fine grains to separate out mutually with noncrystal.This magnetically soft alloy comprises the fine grain of many body-centered cubic lattics, and its crystallite dimension is 30 nanometers (nm) or littler, and its crystal grain quantity is not less than 50% of whole magnetically soft alloy microstructure.

Best, magnetically soft alloy has any composition in the following composition:

Fe _bB _xM _y，

Fe _bB _xM _yX _z，

Fe _bB _xM _yT _d, or

Fe _bB _xM _yT _dX _z, wherein, M is to be an element of selecting from the element set of being made up of titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), molybdenum (Mo) and tungsten (W) at least; The element of T for selecting in the element set of forming by copper (Cu), silver (Ag), gold (Au), palladium (Pd) and platinum (Pt) at least; X is to be an element of selecting from the element set of being made up of silicon (Si), aluminium (Al), germanium (Ge) and gallium (Ga) at least; And subscript b, x, y, d and z represent stoichiometry, they satisfy 75≤b≤93 atomic percentages, and 0.5≤X≤18 atomic percentage, 4≤y≤9 atomic percentage, d is not more than 4.5 atomic percentages and z is not more than 4 atomic percentages.

The content of the numeric representation of b iron (Fe) in magnetically soft alloy, it must be 93 atomic percentages or littler.When the b value surpassed 93 atomic percentages, liquid hardening is handled may obtain noncrystal phase hardly, and the alloy microstructure after the annealing is uneven, caused permeability to reduce.In addition, in order to reach 10 kilogauss (KG) or bigger saturation flux density, the value of b is preferably 75 atomic percentages or bigger.Therefore, the b value is preferably in 75～93 atomic percentage scopes and changes.

Boron (B) can impel the formation of noncrystal phase in the magnetically soft alloy, prevents the crystal structure chap, and minimizing forms the compound phase that magnetic properties is had adverse effect in annealing process.

Though zirconium (Zr), hafnium (Hf), niobium (Nb) etc. can not be dissolved as α-Fe in fact, the amorphous alloy that forms in the quenching process can dissolve these elements by the supersaturation effect.The dissolved element of a part can pass through annealing and crystallization, and separates out as fine grain.The magneto-striction phenomenon of formed alloy band can reduce, and soft magnetic property can improve.In order to separate out fine grain and to restrain the compact grained chap, this is noncrystal must still stay on the grain boundary mutually.Because noncrystal on the grain boundary can be dissolved the M element mutually, for example zirconium (Zr), hafnium (Hf) and niobium (Nb), because temperature raises and is removed from α-Fe, this has just restrained the formation that can worsen the Fe-M compound of soft magnetic property to these elements in annealing process.Therefore, (Hf, it is very important Nb) adding boron (B) in the alloy at Fe-Zr.

When the stoichiometric X value of expression boron (B) during less than 0.5 atomic percentage, the noncrystal instability mutually on the grain boundary.On the other hand, when X value during, can form the boride that B-M system and Fe-B are greater than 18 atomic percentages.Like this, for the annealing conditions that obtains the fine crystallization structure is restricted, and can not obtain superior soft magnetic property.By the content of suitable adjustment boron (B), can be adjusted to 30 nanometers (nm) or littler to the compact grained average-size.

Have any one element in high noncrystal zirconium (Zr), hafnium (Hf) and the niobium (Nb) that forms ability mutually by adding, can the noncrystal phase of easier formation.Part zirconium (Zr), hafnium (Hf) and niobium (Nb) can be with the arbitrary element replacements in titanium (Ti), vanadium (V), tantalum (Ta), molybdenum (Mo) and the tungsten (W) of another element set 4A to the element set 6A.

Because these M elements with low diffusivity can delay the growth of thin nucleus, so these elements are being effective aspect the refinement microstructure.

When the stoichiometric Y value of expression M element during less than 4 atomic percentages, the retarding action of thin nucleus growth is lost, so grain coarsening, and can not obtain superior soft magnetic property.In the Fe-Hf-B alloy, when Hf=5 atomic percentage, average grain size is 13 nanometers (nm), but when Hf=3 atomic percentage, average grain size increases to 39 nanometers (nm).On the other hand, as Y during, can form M-B and Fe-M compound greater than 9 atomic percentages.The formation of these compounds worsens magnetic property, and causes the embrittlement of alloy band later at liquid hardening.Like this, be difficult to this alloy band is made the core shapes that is predetermined.Therefore, preferably the Y value changes in 4～9 atomic percentage scopes.In these elements, because the absolute value of the free energy of niobium (Nb) and molybdenum (Mo) formation oxide is less, so they are heat-staple, and in process of production hardly can be oxidized.Add these elements and can form existing working condition with lower production cost.

Preferably add at least one element of selecting from the element set of being made up of silicon (Si), aluminium (Al), germanium (Ge) and gallium (Ga), its amount is 4 atomic percentages or littler.These elements that are called metalloid element can strengthen the formation ability of noncrystal phase.Their solubilized become bcc (body-centered cubic lattic) phase that is made of iron (Fe) basically, and change the resistivity and the magneto-striction phenomenon of this alloy.When the content of these elements surpassed 4 atomic percentages, magnetostriction increased, and saturation flux density or permeability reduce.

When adding 4.5 atomic percentages or littler at least one element of from the element set of forming by copper (Cu), gold (Au), palladium (Pd) and platinum (Pt), selecting, the soft magnetic characteristic improvement.This element (for example copper (Cu)) that is not dissolved in iron (Fe) of trace promptly causes the change of amorphous alloy composition after quenching.In the primary crystallization stage, copper (Cu) forms many atomic groups in alloy, and like this, because the zone that occurs being rich in Fe in this alloy, therefore, the speed that α-Fe nucleus forms increases.Differential scanning is calorimetric result show, the crystallization temperature of this alloy reduces slightly along with the adding of this element (for example copper (Cu) and/or silver (Ag)).Because this element can cause the stability of noncrystal phase to reduce, therefore, noncrystal mutually may not can being homogenized.In the crystallization process of uneven noncrystal phase, the zone of mass part crystallization forms uneven nucleus, thereby has also just formed the compact grained microstructure.Like this, except given element, any element that can reduce crystallization temperature also all has same effect.

In order to improve the corrosion resistance of this alloy, can add at least a element in the platinum group element, for example chromium (Cr), ruthenium (Ru), rhodium (Rh) and iridium (Ir).But the amount of these elements must be 5 atomic percentages or littler, can significantly reduce saturation flux density because add these elements that surpass 5 atomic percentages.

The magneto-striction phenomenon of the magnetically soft alloy that generates in order to adjust, vacation if required, can also add other elements, for example yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), zinc (Zn), cadmium (Cd), indium (In), tin (Sn), plumbous (Pb), arsenic (As), antimony (Sb), bismuth (Bi), selenium (Se), tellurium (Te), lithium (Li), beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr) and barium (Ba).

Can comprise the impurity of some contingency according to magnetically soft alloy of the present invention, (for example H, N, O and S), but should be in the scope of the soft magnetic characteristic of unlikely deterioration alloy.

When as required when the nozzle tip of crucible is carried inert gas, quench in atmosphere by alloy to fusion, can produce according to magnetically soft alloy of the present invention.Be preferably in and produce this magnetically soft alloy in the vacuum chamber that to regulate its protective atmosphere.By will in crucible, being ejected on the quenching apparatus (for example rotary drum) by the alloy of fusion, and on this quenching apparatus, this alloy is quenched, can produce the magnetically soft alloy band at an easy rate.

Basically constitute mutually by noncrystal through the magnetically soft alloy band after quenching, and then annealing, to separate out a large amount of fine grains.Resulting alloy band has high saturation flux density and superior soft magnetic characteristic.

Utilize this magnetically soft alloy band of forcing press punching press, can make many annulus, again these annulus are piled up, be placed in the container such as resinous housing.Another kind of way is, this magnetically soft alloy band of directly reeling becomes disc, and it is placed in the container (for example resinous housing) or with resin is fixed up.Utilize this method can produce magnetic core with high permeability.The thickness of employed magnetically soft alloy band can suitably decision in 10～40 microns (μ m) scopes.Any quenching process now all may be produced the magnetically soft alloy band of thickness less than 10 microns (μ m) hardly.On the other hand, may form the compact grained microstructure of noncrystal phase hardly above the thickness of 40 microns (μ m).

Through such soft magnetic core that process obtains, when input 0.1V voltage, even when the outside dimension of this soft magnetic core be 10 millimeters (mm) or littler, it highly is 1.2 millimeters (mm) or more hour, its AL value can reach 4.0 microhenrys/newton down at 10 kilo hertzs (kHz) ²(μ H/N ²) or bigger, and under 100 kilo hertzs (kHz), can reach 2.0 microhenrys/newton ²(μ H/N ²) or bigger.Like this, this soft magnetic core can satisfy the fundamental characteristics requirement of pulse converter.

In the magnetic core that uses according to alloy of the present invention, in-40 ℃ to+100 ℃ temperature range, controlled being made as of bias ± 20% of the value of AL value during to room temperature.Because the magnetostrictive absolute value of magnetically soft alloy band is 1 * 10 ^-6Or littler, therefore, when covering with resin or being encapsulated in the resinous housing, can produce hardly because the magnetic characteristic that magnetostriction causes worsens.In addition, package area is not more than 14.0 millimeters (mm) and takes advantage of 14.0 millimeters (mm), and the pulse converter that highly is not more than 3 millimeters (mm) can be according to above-mentioned manufacturing and designing.In addition, be easy to obtain composition in above-mentioned scope, the permeability under 10 kilo hertzs (kHz) is 40,000 or bigger alloy.This alloy is fit to high performance pulse converter to be used.

Above-mentioned AL value is meant the inductance on each circle of coil, can be represented by the formula: AL value=μ o μ ' (S/1), in the formula: S represents the cross-sectional area of toroidal cores, 1 the expression length of magnetic path, μ o represents the permeability in the vacuum, the specific permeability of μ ' expression material.

Can transmit distortionless rectangular wave pulse at 100 kilo hertzs (kHz) or the magnetic core that has stable high inductance below it.In the toroidal cores of making by coiling magnetically soft alloy band, because the restriction of the alloy bandwidth that can make is difficult to produce the magnetic core of thickness less than 1.0 millimeters (mm).On the contrary, in the magnetic core that comprises a plurality of stacked annulus that draw by punching press magnetically soft alloy band, can be easy to make thickness, thereby produce microminiaturized magnetic core less than 1.0 millimeters (mm).

The magnetically soft alloy band is preferably annealed as follows.The magnetically soft alloy band at the first crystallization temperature height of separating out mutually than first crystal, and was annealed 0～20 minute under the low temperature of second crystallization temperature of separating out than second crystalline phase.In order to simplify production process, preferably there is not annealing time, promptly annealing time is 0 minute.

Alloy band after the quenching is basically by noncrystal phase composition.Heat this alloy band can separate out comprise basically bcc (body-centered cubic) crystal grain formed by iron (Fe) and average grain size be 30 nanometers (nm) or littler thin crystalline solid mutually.In the present invention, have the temperature that iron (Fe) the fine crystallization body of bcc structure separates out mutually and be called first crystallization temperature.First crystallization temperature changes with alloy composition, generally in 480 ℃～550 ℃ scopes.

When temperature is higher than first crystallization temperature, the compound phase or second crystal phase, for example Fe ₃Zr (when alloy contains Zr) separates out, and soft magnetic characteristic worsens.In the present invention, this temperature is called second crystallization temperature.Second crystallization temperature also changes with alloy composition, generally in 740 ℃～810 ℃ scopes.

Therefore, according to the difference of alloy composition, the annealing temperature of amorphous alloy band determines that in 500 ℃ to 800 ℃ scopes like this, the bcc fine crystallization body of being made up of iron (Fe) is separated out mutually basically, and above-mentioned compound is not separated out mutually.

Can be in 20 minutes or littler scope according to the annealing time of amorphous alloy band of the present invention.According to the difference of alloy composition, annealing time is 0 minute, i.e. cooling immediately after heating also can obtain high permeability.The composition that does not contain copper (Cu) and silicon (Si), particularly silicon (Si) can obtain high permeability in 10 minutes or littler short annealing time.When adding silicon (Si), be dissolved in the iron (Fe) in order to make Si fully, need long annealing time.Prolong annealing time again and can cause productivity ratio to reduce, and magnetic characteristic can't be improved.

The amorphous alloy band is heated to the rate of heat addition of annealing temperature in 20 ℃/minute～200 ℃ of/minute scopes from room temperature, be preferably in 40 ℃/minute～200 ℃ of/minute scopes to change.Though, higher in order to shorten the best rate of heat addition of production time, be difficult to reach than 200 ℃ of/minute high again rates of heat addition with common heater.After the annealing, the alloy band cools off in media such as air.

The result of annealing can obtain the amorphous alloy band, promptly comprise 50% or more, basically form by iron (Fe), and average grain size is the alloy of 30 nanometers (nm) or littler thin bcc crystal grain phase, and can makes the compound phase that magnetic characteristic worsens (Fe for example ₃B) can not separate out.The microstructure that the result obtains is made of with the border that exists on the grain boundary is noncrystal mutually mutually the compact grained crystal basically.This microstructure has superior soft magnetic characteristic.

This annealed alloy has the reasons are as follows of superior soft magnetic characteristic: because the magnetic interaction of thin bcc intergranule, make the crystalline material anisotropy that becomes a factor that causes common crystalline material soft magnetic characteristic deterioration be flattened, and apparent magnetic anisotropy obviously reduce.If average grain size is greater than 30 nanometers (nm), then owing to the magnetic anisotropy planarization fully of crystal, soft magnetic characteristic can worsen.On the other hand, the fine crystallization body is less than 50% mutually makes the magnetic interaction of intergranule lower, and therefore, soft magnetic characteristic also can worsen.

Embodiment 1

Punching press thickness is 15～25 microns (μ m), has Fe ₈₆Nb _3.25Zr _3.25B _6.5Cu ₁It is that 7.8 millimeters (mm) and internal diameter are the annulus of 4.8 millimeters (mm) that the magnetically soft alloy band of composition is made external diameter, and this annulus is annealed under 510～540 ℃ temperature.It is 9 millimeters (mm) that the annealed annulus that is predetermined quantity is put into external diameter, internal diameter is 4 millimeters (mm), highly be that making magnetic core height (annulus thickness * annulus number) is 0.3～0.95 millimeter (nm) in circular PET (polyethylene terephthalate) resin-case of 1.5 millimeters (mm).Need decision impedance and permeability.The used enclosure interior degree of depth is 1.0 millimeters (mm).

(result of the test 1)

Fig. 5 for the expression impedance (| the Z|) figure that (%) changes with encapsulation rate (packing rate), this encapsulation rate are to be 15 microns (μ m) from thickness, have the internal depth of above-mentioned composition and housing, use the magnetic core high computational of 20 circle leads to come out.The figure that Fig. 6 changes with encapsulation rate (%) for expression permeability (μ ').

In each annulus is layered in this version in the housing, the vertical stress of annulus and material therefor intrinsic magneto-striction phenomenon permeability is reduced.Yet, because have Fe ₈₆Nb _3.25Zr _3.25B _6.5Cu ₁The magnetostriction constant of the magnetically soft alloy band of composition is very little, promptly is approximately-0.3 * 10 in annealing under 540 ℃ after 30 minutes ^-6, therefore, even be approximately in the encapsulation rate under 90% the situation, stress can not make permeability reduce yet, and impedance increases and increases along with the encapsulation rate, and as shown in Figure 5 and Figure 6.Therefore, in order to obtain high impedance, preferably encapsulation rate is high as far as possible.

Table 1 expression encapsulation rate is 92～93% o'clock, the thickness of magnetically soft alloy band and when importing 0.1 volt of (V) voltage, viewed AL value (inductance of each circle of AL value representation coil).

When 100 kilo hertzs (kHz) during table 1 thickness (μ m) 10 kilo hertzs (kHz)

AL value microhenry/newton ²(μ H/N ²) AL value microhenry/newton ²(μ H/N ²) 15.2 5.73 3.3315.7,6.09 3.2716.3,5.73 3.0416.6,5.58 3.0019.5 5.93 2.77

Fig. 7 is the figure that the AL value when representing 10 kilo hertzs (kHz) and 100 kilo hertzs (kHz) changes with the magnetically soft alloy tape thickness.As everyone knows, in the magnetic core that uses the magnetically soft alloy band, general eddy current loss is along with the thickness of magnetically soft alloy band increases and increases, and therefore, high frequency permeability and inductance reduce.Use is according to the magnetic core of magnetically soft alloy band of the present invention, and the AL value when 100 kilo hertzs (kHz) also reduces with the thickness increase of this magnetically soft alloy band, as shown in Figure 7.Yet the AL value when 10 kilo hertzs (kHz) reaches 25 microns (μ m) at this magnetically soft alloy tape thickness and before, does not change basically.

For the pulse transformer of above-mentioned isdn standard, its AL value when 100 kilo hertzs (kHz) is preferably 2.0 microhenrys/newton ²(μ H/N ²) or bigger.When as mentioned above, by having Fe ₈₆Nb _3.25Zr _3.25B _6.5Cu ₁Composition, thickness be 25 microns (μ m) or littler magnetically soft alloy band to make external diameter be 7.8 millimeters (mm), internal diameter is 4.8 millimeters (mm), when highly being the toroidal cores of 0.92～0.93 millimeter (mm), can obtain such AL value.Though, the thickness of magnetically soft alloy band can suitably determine in 10～25 microns (μ m) scopes, but consider the working condition of this magnetically soft alloy band of simplification and the stack thickness of pulse transformer, the thickness of magnetically soft alloy band is preferably in 15～20 microns (μ m) scopes.

Embodiment 2

Utilization has Fe ₈₄Nb _3.5Zr _3.5B ₈Cu ₁Composition, thickness are the magnetically soft alloy band of 16 microns (μ m).Through punching press and 520 ℃ of manufacturing external diameters of annealing down is 7.8 millimeters (mm), and internal diameter is the annulus of 4.8 millimeters (mm).The magnetostriction constant of alloy band is approximately+and 0.6 * 10 ^-6It is that 9 millimeters (mm), internal diameter are 4 millimeters (mm), highly are the resin-case of 1.5 millimeters (mm) that the annulus of given number is put into external diameter, require its impedance of decision (| Z|) and magnetic permeability mu ', the height that makes magnetic core is 0.5～0.9 millimeter (mm).

(result of the test 2)

The figure that Fig. 8 changes with encapsulation rate (%) for the expression impedance, this encapsulation rate is to calculate from the magnetic core height that uses 20 circle leads and the internal depth of housing.The figure that Fig. 9 changes with encapsulation rate (%) for the expression permeability.Fig. 8 and Fig. 9 have also represented to have Fe used among the embodiment 1 ₈₆Nb _3.25Zr _3.25B _6.5Cu ₁The result of the magnetically soft alloy band of composition.The permeability of the magnetic core in this example is higher than at 60% o'clock in the encapsulation rate and reduces gradually, and when the encapsulation rate is higher than 75% and since material intrinsic magnetostriction and the influence of encapsulation stress, the permeability of magnetic core reduces greatly.Impedance when 10 kilo hertzs (kHz) that is directly proportional with magnetic core permeability and cross-sectional area and 100 kilo hertzs (kHz) is approximately at 70% o'clock in the encapsulation rate and reaches maximum.

In order to compare, Fig. 8 and Fig. 9 have represented to have Fe _73.5Si _13.5B ₉Nb ₃Cu ₁The result of the fine crystallization body magnetically soft alloy band of composition.Thickness is this magnetically soft alloy band of 19.6 microns (μ m), and the magnetostriction constant after annealing under 530 ℃ is+1.3 * 10 ^-6, and the magnetic permeability mu when 1 kilo hertz (kHz) ' be 80,000.This magnetically soft alloy band is highly brittle, and permeability reduces when low frequency, and thickness is the sample of 15 microns (μ m), the magnetic permeability mu when 1 kilo hertz (kHz) ' be approximately 50,000.Therefore, the sample with this thickness is not used in and tests.

Supply the relatively impedance of this alloy of usefulness when lower encapsulation rate, to begin to reduce.This may be because, when the encapsulation rate in the housing increased, magnetostriction caused the tremendous influence of permeability.On the contrary, in using the magnetic core of making according to magnetically soft alloy band of the present invention, impedance just begins to reduce when very high encapsulation rate.

Figure 10 is the AL value of the same sample shown in presentation graphs 8 and Fig. 9 and the dependency relation figure between the encapsulation rate.Figure 10 points out, two lower limiting values when removing 10 kilo hertzs (kHz) and 100 kilo hertzs (kHz), when magnetic core has when comprising the structure that is encapsulated in a plurality of magnetically soft alloy annulus in the resin-case, the encapsulation rate is preferably 50% or bigger, and 55～80% is just better.

Embodiment 3

(result of the test 3)

Figure 11 is the figure of expression permeability with the magnetic core variations in temperature, and this magnetic core can be 80% magnetic core and FERRITE CORE for employed in embodiment 1 and embodiment 2, encapsulation rate.Figure 11 shows, employing is according to magnetically soft alloy of the present invention, and be encapsulated in transformer (: embodiment 1, C: embodiment 2) in the resin-case, in-20～+ 100 ℃ large-temperature range, permeability changes minimum, specifically, in-20～+ 70 ℃ of scopes, approximately change ± 5%, and in-20～100 ℃ of scopes, change+5～-10%.Therefore, compare with comparative example's permeability variation, less significantly according to the permeability variation of transformer of the present invention.

Embodiment 4

With width is 0.9 millimeter (mm), has Fe ₈₄Nb _3.5Zr _3.5B ₃Cu ₁The magnetically soft alloy band of composition is rolled into the magnetic core main body that dish type is made an annular, this magnetic core main body is annealed under 650～690 ℃ temperature, the external diameter that makes this magnetic core main body is 8.8 millimeters (mm), and internal diameter is 4.2 millimeters (mm), highly is 0.9 millimeter (mm).Annealed magnetic core main body viscosity is silicone rubber (TSE3051 that silicone company of the Toshiba produces) dipping of 0.7 handkerchief second (Pas), and heats under 110～140 ℃ temperature, and silicone rubber is solidified.

The magnetic core housing that has the described opening of Fig. 3 is made by aldehyde resin.Viscosity is 1.5 handkerchiefs second (Pas) before will solidifying, and solidifies back JISA hardness and be two positions that 19 silicone rubber (TSE3991 that silicone company of Toshiba produces) is coated in the bottom surface, and the area at every place is 1 millimeter ²(mm ²).The external diameter of magnetic core housing is 9.5 millimeters (mm), and internal diameter is 3.5 millimeters (mm), highly is 1.15 millimeters (mm), and thickness is 0.15 millimeter (mm).Inwall two ends and outer wall two ends of magnetic core housing have the radius of curvature of 0.1 millimeter (mm) respectively.

The magnetic core main body is placed in the magnetic core housing, and the silicone rubber on the magnetic core housing bottom surface at room temperature solidifies, with the fixed magnetic core main body.So just made pulse transformer.

Embodiment 5

Except magnetic core floods without silicone rubber, as embodiment 4, make pulse transformer.

(result of the test 4)

The magnetic core main body of coiling around embodiment 4 and embodiment 5 is rolled into dish type and makes transformer, and this magnetic core main body is not placed in the magnetic core housing.Also coiling can be rolled into dish type and make transformer around the magnetic core main body in the magnetic core housing that is placed on embodiment 4 and embodiment 5.When input during 0.1 volt (V) voltage, measure the AL value of these transformers when 10 kilo hertzs (kHz), and determine after the magnetic core main body is fixed on the magnetic core housing with putting into this housing before the rate of change of AL value.The results are shown in the table 2, the unit of AL value is microhenry/newton in the table ²(μ H/N ²).

Table 2

Resin impregnation is put into the fixing rate of change afterwards of housing

The AL value embodiment 4 of preceding AL value has flooded 6.98 6.87-1.58 embodiment 5 and has not flooded 6.70 6.48-3.28

(result of the test 5)

Coiling is centered on the magnetic core of preparing among embodiment 4 and the embodiment 5 to be rolled into dish type and to make pulse transformer.When 0.1 volt of (V) voltage of input, when in-50～100 ℃ of scopes, changing atmospheric temperature simultaneously, measure the AL value of the pulse transformer under 10 kilo hertzs (kHz).Determine AL value under each temperature to the rate of change of the AL value under 20 ℃.The result is illustrated among Figure 12, and solid line is represented the magnetic core of the pulse transformer among the embodiment 4 among the figure, and dotted line is represented the magnetic core of pulse transformer among the embodiment 5.Experimental result 4 shows, though can reach the little rate of change of big AL value and AL value among the embodiment 5, yet by the magnetic core main body being immersed in after the curing in the silicone rubber that can gelling gets up, can relax the magnetic core main body and be fixed on the stress that is produced on the magnetic core housing, the result can make the deterioration of AL further improve.

As testing as described in the result 5, with embodiment 5 relatively, with the magnetic core main body be immersed in by solidify can the silicone rubber of gelling in, can further suppress the deterioration of AL under the high temperature.

Embodiment 6

Except the size of magnetic core main body and magnetic core housing changes, make the magnetic core of pulse transformer as embodiment 4 as described in the following table 3.

Embodiment 7

Make a use comprise as shown in Figure 2 upper shell and the magnetic core of pulse transformer of the magnetic core housing of lower house.The size of magnetic core housing and magnetic core main body is as shown in table 3.

With width is 0.7 millimeter (mm), has Fe ₈₄Nb _3.5Zr _3.5B ₈Cu ₁The magnetically soft alloy band of composition is rolled into dish type, and anneals under 650～690 ℃ temperature and make the magnetic core of an annular.Annealed magnetic core main body is placed in the magnetic core housing by aldehyde resin system.

(result of the test 6)

Coiling is centered on the magnetic core of pulse transformer of preparing among embodiment 6 and the embodiment 7 be rolled into dish type and make transformer, and when 0.1 volt of (V) voltage of input, measure the AL value under 10 kilo hertzs (kHz).The AL value rate of change result of decision embodiment 7 to embodiment 6 is illustrated in the table 3.In embodiment 6, as the mean value of 10 magnetic core main bodys,, to put into to the magnetic core housing when input during 0.1 volt of (V) voltage, the AL value of this magnetic core main body under 10 kilo hertzs (kHz) is 8.6 microhenrys/newton ²(μ H/N ²).

Table 3

Embodiment 6 embodiment, 7 shell dimensions (mm)

External diameter 9.5 9.5

Internal diameter 3.5 3.5

Height 1.2 1.2

Thickness 0.15 0.15 magnetic core size of main body (mm)

External diameter 8.8 8.4

Internal diameter 4.2 4.2

Height 0.9 0.8 AL value (μ H/N ²) 7.79 6.49 rates of change 20.0 0.0

Table 3 is listed result show, the AL value is bigger in embodiment 6.Magnetic core size of main body among the embodiment 6 (external diameter, internal diameter and height) is bigger than the magnetic core size of main body among the embodiment 7, because do not adopt upper shell among the embodiment 6, and the magnetic core thickness of shell reduces.As a result, compare with embodiment 7, the cross-sectional area of magnetic core main body increases, and the AL value has also improved 20% or more.

Embodiment 8

(external diameter is 9.5 millimeters (mm) will to put into the magnetic core housing with the same magnetic core main body among the embodiment 4, internal diameter is 3.5 millimeters (mm), highly be 1.15 millimeters (mm), thickness is 0.15 millimeter (mm)) in, and be 1.3 handkerchiefs second (Pas) with viscosity before solidifying, JISA hardness is 9 silicone rubber (TSE3250 that silicone company of Toshiba produces) dipping after solidifying, and then is cured.

Coiling is rolled into dish type around magnetic core makes pulse transformer, and determine its AL value.Because the characteristic of the transformer among the embodiment 8 does not have to worsen owing to the stress influence of silicone rubber, therefore, compare with embodiment 4, AL value (mean values of 10 transformers) has also been improved, and reaches 8.6～10 microhenrys/newton ²(μ H/N ²).

The preferred example of the magnetically soft alloy that is used for pulse transformer is produced in open-birth now.

Embodiment 9

As alloy embodiment according to the present invention, have a Fe ₈₄Nb _3.5Zr _3.5B ₈Cu ₁The amorphous alloy band of composition utilizes production equipment shown in Figure 13 to produce.

In process units shown in Figure 13, be provided with cooling and roll 35 and comprise the main part 13 and the retaining part 14 that is connected with this prismatic main part 13 of prismatic with the chamber 10 of crucible 12.Main part 13 and retaining part 14 utilize screw, are tightly connected each other by flange section 13a and 13b.The main part 13 in chamber 10 is provided with the blast pipe 15 that is connected with pumped vacuum systems.Gyroaxis 11 is supporting cooling and is rolling 35.Gyroaxis 11 passes two sidewalls in chamber 10, and by motor-driven (not illustrating among the motor figure).Be provided with nozzle 37 in the bottom of crucible 12, be provided with heater coil 38 in the bottom of crucible 12.Melt metal 34 is kept in the crucible 12.

The top of crucible 12 is connected with air supply source 18, for example is used for, and carries argon gas (Ar) by air duct 16.Pressure-control valve 19 and electromagnetically operated valve 20 are housed on the air duct 16.Between pressure-control valve 19 and electromagnetically operated valve 20, Pressure gauge 21 is housed.Air duct 16 is provided with a by-pass line 23, it and pressure controlled quentity controlled variable instrument 24, and flow control valve 25 is parallel with flowmeter 26.The pressure that motlten metal 34 in the crucible 12 produces by the hydrogen (Ar) that is sent to crucible from air supply source 18 is ejected into cooling by nozzle 37 and rolls on 35.The roof in chamber 10 is provided with air duct 32.Air duct 32 is equipped with the pressure-control valve 33 that is connected with air supply source 31.Air supply source 31 for example is used for, and carries hydrogen (Ar) to chamber 10.

Utilize this process units, can produce the alloy band by the following method: when air supply source 31 is sent non-oxidizing gas (for example argon gas (Ar)) into chamber 10, chamber 10 is vacuumized.Melt metal 34 is sent into the pressure of the argon gas (Ar) of crucible 12 by air supply source 31, and the cooling that is injected into high speed rotating by nozzle 37 is rolled on 35 the top.Melt metal 34 is rolled 35 surface along cooling and is rolled, and forms strip 36.

From crucible 12, melt metal 34 is injected into cooling continuously and rolls on 35, just produce long strip 36 serially.Strip 36 rolls 35 from cooling and pulls out, and remains in the retaining part 14 in chamber 10.Because chamber 10 is full of hydrogen (Ar), therefore can prevent because still red-hot strip 36 oxidations of thermal inertia.After producing strip, when being cooled to strip 36 near room temperature, with retaining part 14 from the chamber 10 main part 13 pull down, take out strip 36.

Utilizing differential scanning calorimetry (DSC), is under 40 ℃/minute in the rate of heat addition, and the decision width is 15 millimeters (mm), and thickness is the crystallization temperature of the amorphous alloy band that is drawn of 20 microns (μ m).Like this, can obtain the DSC thermogram represented with solid line among Figure 14.The result shows that under 40 ℃/minute the rate of heat addition, the first crystallization temperature Tx of this amorphous alloy band is about 508 ℃.

Comparative example 1

Produce a kind of Fe of having again _73.5Si _13.5B ₉Nb ₃Cu ₁The amorphous alloy strip of composition is as a kind of alloy example beyond the scope of the invention among the embodiment 9.Under 40 ℃/minute the rate of heat addition, utilize differential scanning calorimetry (DSC) to determine the crystallization temperature of the amorphous alloy strip that this draws.Like this, obtain a DSC thermogram dotting among Figure 14.The result shows that the first crystallization temperature Tx of this amorphous alloy strip is approximately 548 ℃.

In order to make magnetically soft alloy, the amorphous alloy strip that obtains in embodiment 9 and the comparative example 1 is carried out annealing in process in different retention time t.Utilize the magnetically soft alloy drawn to estimate magnetic characteristic, i.e. permeability under 1 kilo hertz (kHz), coercive force Hc (Oe), saturation magnetostriction λ s and average grain size D nanometer (nm).

Heating schedule is as follows: under 40 ℃/minute the rate of heat addition, each amorphous alloy strip is heated to given maintenance temperature T a, keeps keeping one given period under the temperature at this, then cooling.Keep temperature T a to be set at the temperature brighter a little, promptly at Fe than first crystallization temperature of this alloy ₈₄Nb _3.5Zr _3.5B ₈Cu ₁Be 510 ℃ in (embodiment 9), and at Fe _73.5Si _13.5B ₉Nb ₃Cu ₁It is 550 ℃ in (comparative example 1).The result is illustrated among Figure 15 to Figure 17, among the figure ● represent embodiment 9, zero to represent comparative example 1.

Figure 15 shows, in embodiment 9, in 0～20 minute short retention time, promptly reached higher permeability, and the sample of comparative example 1 and be the permeability that when the retention time is about 30 minutes, just reaches maximum, and when the short retention time, permeability sharply reduces.

Figure 16 shows that the coercive force in embodiment 9 and the comparative example 1 does not change with the retention time basically, and almost on a horizontal line.In comparative example 1, saturation magnetostriction λ s increases along with reducing of retention time, and the sample among the embodiment 9, in 0～20 minute short retention time, its saturation magnetostriction is always littler than the saturation magnetostriction in the comparative example 1.

Figure 17 shows that in embodiment 9 and comparative example 1, average diameter D does not change basically, and the sample among the embodiment 9, its average diameter is littler than the average diameter in the comparative example 1.

These results show, in 0～20 minute short retention time, the sample in embodiment 9 and the comparative example 1 has coercive force about the same, and superior than comparative example 1 of permeability and saturation magnetostriction.In addition, in embodiment 9, the less soft magnetic characteristic that makes of average grain size has such improvement.

Under different maintenance temperature T a, in 0 minute retention time, the non-crystaline amorphous metal of manufacturing among the embodiment 9 is annealed, measure the magnetic permeability mu of the magnetically soft alloy that is drawn under 1 kilo hertz (kHz) ' variation.Under 40 ℃/minute the rate of heat addition, amorphous alloy strip is heated to given maintenance temperature T a, cooling is immediately annealed so then.Keep temperature T a in 480 ℃～800 ℃ scopes, to change.The result is illustrated among Figure 18.Figure 18 shows that under 500～700 ℃ temperature, not the retention time, when annealing like this, the permeability of the amorphous alloy strip of embodiment 9 is higher.

Embodiment 10

As in Example 9, make one and have Fe ₈₄Nb ₇B ₉Composition according to amorphous alloy strip of the present invention.

Embodiment 11

As in Example 9, make one and have Fe ₉₀Zr ₇B ₃Composition according to amorphous alloy strip of the present invention.

In different retention time t, the amorphous alloy strip of making among embodiment 10 and the embodiment 11 is annealed, and estimate under 1 kilo hertz (kHz) magnetic permeability mu of first kind of magnetically soft alloy after the annealing '.

Cycle of annealing is included under 180 ℃/minute the rate of heat addition, is heated to given maintenance temperature T a, keeps one given period, then cooling.The maintenance temperature T a of each sample is arranged to the first crystallization temperature height than this sample, and than the low temperature of second crystallization temperature, promptly to Fe ₈₄Nb ₇B ₉(embodiment 10) are 650 ℃, to Fe ₉₀Zr ₇B ₃(embodiment 11) are 600 ℃.The result is illustrated among Figure 19, among the figure ● expression embodiment 10, zero represents comparative example 11.Figure 19 shows that the sample among the embodiment 10 at 1～120 minute, preferably in 2～30 minutes retention time, have bigger permeability, and the sample among the embodiment 11 at 0～120 minute, preferably has higher permeability in 2～30 minutes.

Claims

1. magnetic core of pulse transformer, it is characterized by it and comprise that one is the magnetic core main body that 25 microns (μ m) or littler magnetically soft alloy band are made by thickness, when 0.1 volt of (V) voltage of input, the AL value of the described magnetic core main body under 10 kilo hertzs (kHz) is 4.0 microhenrys/newton ²(μ H/N ²) or bigger.

2. magnetic core of pulse transformer as claimed in claim 1, it is characterized by, described magnetic core main body comprises a plurality of stacked annulus of being made by described magnetically soft alloy band, and the external diameter of described magnetic core main body is 10 millimeters (mm) or littler, and thickness is 1.2 millimeters (mm) or littler.

3. magnetic core of pulse transformer as claimed in claim 1, it is characterized by, described magnetic core main body comprises an E-shape magnetic core and an I-shape magnetic core, any compound mode in U-shape magnetic core and I-shape magnetic core and two the U-shape magnetic cores, described E-shape magnetic core, described I-shape magnetic core and described U-shape magnetic core are the E-shape thin slices that will be made by described magnetically soft alloy band respectively, and I-shape thin slice and U-shape sheet stacking constitute, the thickness of described magnetic core main body is 1.2 millimeters (mm), or littler.

4. magnetic core of pulse transformer as claimed in claim 1, it is characterized by, it is that 1.2 millimeters (mm) or littler magnetically soft alloy band are rolled into the annulus that dish type constitutes that described magnetic core main body comprises width, and the external diameter of described toroidal cores main body is 10 millimeters (mm) or littler.

5. magnetic core of pulse transformer as claimed in claim 2 is characterized by, described annulus with 50% or bigger encapsulation rate be encapsulated in the lid that is formed from a resin.

6. magnetic core of pulse transformer as claimed in claim 1 is characterized by, and the magnetostrictive absolute value of described magnetically soft alloy band is 1 * 10 ^-6Or it is littler.

7. magnetic core of pulse transformer as claimed in claim 1 is characterized by, in-40 ℃～+ 100 ℃ temperature range, the AL value of described magnetic core of pulse transformer to the bias of the AL value under the room temperature in ± 20%.

8. magnetic core of pulse transformer as claimed in claim 1 is characterized by, and described magnetic core main body is 1 handkerchief second (Pas) or littler with viscosity before solidifying, silicone rubber dipping that can gelling is got up by curing.

9. magnetic core of pulse transformer as claimed in claim 1, it is characterized by, described magnetic core main body is 1.5 handkerchiefs second (Pas) or littler with viscosity before solidifying, JISA hardness is 10 or littler silicone rubber dipping, described silicone rubber can play the bonding agent effect, is used for described magnetic core main body is fixed on the magnetic core housing.

10. magnetic core of pulse transformer as claimed in claim 9, it is characterized by, described being used for is fixed on the described magnetic core housing bonding agent for viscosity before solidifying is 2 handkerchiefs second (Pas) or littler with described magnetic core main body, solidifies back JISA hardness and be 25 or littler silicone rubber.

11. magnetic core of pulse transformer as claimed in claim 10 is characterized by, described adhesive applicating is on 2～4 parts of described magnetic core housing bottom surface.

12. magnetic core of pulse transformer as claimed in claim 1, it is characterized by, 50% or more described magnetically soft alloy form by the body-centered cubic fine grain basically, the average-size of crystal grain is 30 nanometers (nm) or littler, described magnetically soft alloy comprises that iron (Fe) is as Main Ingredients and Appearance, having an element at least is from by Ti (titanium), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta) is selected in the element set that molybdenum (Mo) and tungsten (W) and boron (B) are formed.

13. a magnetic core of pulse transformer is characterized by it and comprises: one by the magnetically soft alloy band that is rolled into annular magnetic core main body that constitutes and the magnetic core housing with the opening that is used for fixing described magnetic core main body.

14. magnetic core of pulse transformer as claimed in claim 13 is characterized by, the two ends of the inner and outer wall of described magnetic core housing have the radius of curvature of 0.05～0.4 millimeter (mm).

15. magnetic core of pulse transformer as claimed in claim 13 is characterized by, described magnetic core main body with 50% or bigger encapsulation rate be encapsulated in the described magnetic core housing.

16. magnetic core of pulse transformer as claimed in claim 13 is characterized by, the magnetostriction absolute value of described magnetic alloy band is 1 * 10 ^-6Or it is littler.

17. magnetic core of pulse transformer as claimed in claim 13 is characterized by, described magnetic core main body is 1 handkerchief second (Pas) or littler with viscosity before solidifying, can be by solidifying the silicone rubber dipping that gelling is got up.

18. magnetic core of pulse transformer as claimed in claim 13, it is characterized by, described magnetic core main body is 1.5 handkerchiefs second (Pas) or littler with viscosity before solidifying, JISA hardness is 10 or littler silicone rubber dipping, described silicone rubber plays the bonding agent effect, is used for described magnetic core main body is fixed on the magnetic core housing.

19. magnetic core of pulse transformer as claimed in claim 13, it is characterized by, the described bonding agent that is used for described magnetic core main body is fixed on the described magnetic core housing is 2 handkerchiefs second (Pas) or littler for viscosity before solidifying, and solidifies back JISA hardness and be 25 or littler silicone rubber.

20. magnetic core of pulse transformer as claimed in claim 19 is characterized by, described adhesive applicating is on 2～4 parts of described magnetic core housing bottom surface.

21. magnetic core of pulse transformer as claimed in claim 13, it is characterized by, the external diameter of described magnetic core housing is 10 millimeters (mm) or littler, internal diameter is 3.5 millimeters (mm) or bigger, highly be 1.3 millimeters (mm) or littler, when 0.1 volt of (V) voltage of input, the AL value under 10 kilo hertzs (kHz) is 6.0 microhenrys/newton ²(μ H/N ²) or bigger.

22. magnetic core of pulse transformer as claimed in claim 13, it is characterized by, 50% or more described magnetically soft alloy constitute by the body-centered cubic fine grain basically, average grain size is 30 nanometers (nm) or littler, described magnetically soft alloy comprises that iron (Fe) is as Main Ingredients and Appearance, having an element at least is from by titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta) is selected in the element set that molybdenum (Mo) and tungsten (W) and boron (B) are formed.