CN103227020A - Powder mixture for dust cores - Google Patents
Powder mixture for dust cores Download PDFInfo
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- CN103227020A CN103227020A CN2013100207572A CN201310020757A CN103227020A CN 103227020 A CN103227020 A CN 103227020A CN 2013100207572 A CN2013100207572 A CN 2013100207572A CN 201310020757 A CN201310020757 A CN 201310020757A CN 103227020 A CN103227020 A CN 103227020A
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—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
- H01F1/20—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 in the form of particles, e.g. powder
- H01F1/22—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 in the form of particles, e.g. powder pressed, sintered, or bound together
- H01F1/24—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 in the form of particles, e.g. powder pressed, sintered, or bound together the particles being insulated
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- 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
- H01F27/255—Magnetic cores made from particles
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F3/00—Cores, Yokes, or armatures
- H01F3/08—Cores, Yokes, or armatures made from powder
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- 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
- H01F41/0246—Manufacturing of magnetic circuits by moulding or by pressing powder
Abstract
The invention provides a powder mixture for dust core, which contains an insulated skin and lubrican on the surface of soft magnetic iron-based powder. When applying a heat process for a shaping body obtained by the powder mixture, a demensional change of the shaping body before and after the heat process is reduced, especially expansion caused by the heat process is inhibited. The powder mixutre whose grain size is below 106 mu m is more than 95% of the total powder mixture by mass, and the powder mixutre whose grain size is below 45 mu m is less than 40% of the total powder mixture by mass (40% is excluded).
Description
Technical field
Employed soft magnetic iron-based powder when the present invention relates to make the compressed-core that is used for the electromagnetic component of inductor etc. for example.
Background technology
The electromagnetic component of inductor etc. is many to be used in AC magnetic field, uses magnetic core (core) in this electromagnetic component.This magnetic core is always processed stacked electromagnetic steel plate and is made.But the resulting magnetic core of processing electromagnetic steel plate is because magnetic characteristic has directivity, so design has the electromagnetic component difficulty of three-dimensional magnetic circuit.So in recent years, the technology of making dust core by the press molding soft magnetic iron-based powder obtains research.Because its magnetic characteristic of dust core is an isotropism, can design electromagnetic component with three-dimensional magnetic circuit.
Compressed-core is owing to employed frequency, and electromagnetic conversion characteristics has the tendency of deterioration.The deterioration of electromagnetic conversion characteristics is because the energy loss (iron loss) in magnetic when conversion causes, if do not follow the zone of the mitigation phenomenon (magnetic resonance etc.) of flux change in the material, is then decreased by eddy current and magnetic hysteresis is decreased and represent.When particularly excitation frequency is high frequency (for example, more than the 1kHz), compares magnetic hysteresis and decrease the influence that iron loss is caused, it is bigger that eddy current decreases the influence that iron loss is caused, and therefore requires to reduce eddy current and decrease.
Among the iron loss, decrease in order to reduce eddy current, known surface with insulating coating lining soft magnetic iron-based powder gets final product.Surface by with insulating coating lining soft magnetic iron-based powder can suppress the generation of interparticle vortex flow, because vortex flow is only in particle, so the eddy current that can reduce as a whole decreases.As insulating coating, can use the inorganic epithelium (for example, phosphoric acid system change into epithelium, waterglass epithelium, oxide epithelium etc.) of insulating properties and resin involucra (for example, silicones epithelium etc.).In addition, decrease, use the little soft magnetic iron-based powder of particle diameter also effective in order to reduce eddy current.On the other hand, decrease in order to reduce magnetic hysteresis, the known coercive force that is reduced to the formed body that forms soft magnetic iron-based powder and obtain is implemented heat treatment for formed body for this reason and is got final product.Because the strain that coercive force imports when being shaped is many more and big more, so, if after shaping, implement heat treatment (going strain annealing), discharge the strain that is imported, then the coercive force of formed body diminishes.Consequently magnetic hysteresis is decreased and is diminished.
Making eddy current damage and magnetic hysteresis decrease the compressed-core that reduces and iron loss is reduced is disclosed in the patent documentation 1.This compressed-core has and is characterised in that, is insulated the soft magnetic powder particle that layer carried out insulation-coated processing by the surface and constitutes, and this insulating barrier is made of not resiniferous inorganic matter, residual compression stress not in this soft magnetic powder particle.Recording and narrating in the document, is in the soft magnetic powder of 10～150 μ m in average grain diameter, and mixing average grain diameter is the oxide powder of 0.1～10 μ m, heats after this mixed-powder is configured as the regulation shape, makes compressed-core thus.
In addition, shaping soft magnetic iron-based powder and when making compressed-core, in order to reduce between the powder when the shaping soft magnetic iron-based powder, or the friction impedance between powder and shaping dies inwall, prevent the sticking to mould of compressed-core and the heat release when being shaped, in soft magnetic iron-based powder, form again after the hybrid lubricant (for example, patent documentation 2).
[look-ahead technique document]
[patent documentation]
[patent documentation 1] spy opens the 2003-332116 communique
[patent documentation 2] special fair 4-64441 communique
, if be formed in the mixed-powder that is combined with lubricant in the soft magnetic iron-based powder, and resulting formed body is implemented heat treatment, then before and after heat treatment, the size of formed body changes, because heat treatment causes formed body to expand.And the formed body that expands owing to heat treatment, the tendency that has magnetic characteristic to reduce.When particularly formed body is the inductor of outer iron shape, owing to expanding problems such as producing the reduction of inductance Ga.
Summary of the invention
The present invention forms in view of such situation, its purpose is, provide a kind of containing to have the powder of insulating properties epithelium and the compressed-core mixed-powder of lubricant on the surface of soft magnetic iron-based powder, wherein, when the formed body that obtains for being shaped this mixed-powder is implemented heat treatment, can reduce the change in size of the formed body of heat treatment front and back, particularly can suppress the expansion that causes by heat treatment.
Can solve the compressed-core mixed-powder so-called of the present invention of above-mentioned problem, be to contain to have the powder of insulating properties epithelium and the compressed-core mixed-powder of lubricant on the surface of soft magnetic iron-based powder, it has following some main idea: with respect to the overall quality of described mixed-powder, particle diameter is that the mass ratio of the following mixed-powder of 106 μ m is more than 95%, and particle diameter is that the mass ratio of the following mixed-powder of 45 μ m is (not contain 0%) below 40%.
The mass ratio of described lubricant, preferably overall with respect to described mixed-powder quality is 0.6～1%.As described insulating properties epithelium, for example, be preferably formed the inorganic epithelium of insulating properties.On the surface of the inorganic epithelium of described insulating properties, also can form the insulative resin epithelium again.Above-mentioned compressed-core can be used in inductor with mixed-powder.
In the present invention, also comprise the compressed-core that uses above-mentioned compressed-core to obtain with mixed-powder.Compressed-core of the present invention, for example, can be after the above-mentioned compressed-core that is shaped be with mixed-powder, by in non-oxidizing atmosphere, making to heat-treat more than 400 ℃.
According to the present invention, suitably control has the particle size distribution of the mixed-powder of the soft magnetic iron-based powder of insulating properties epithelium and lubricant, therefore if the formed body that obtains for being shaped this mixed-powder is implemented heat treatment, then lubricant volatilization and the gas componant that takes place is emitted from formed body inside can be suppressed to the expansion of body.The density that therefore can prevent the formed body that causes because of heat treatment reduces, and can suppress the deterioration of magnetic characteristic (particularly permeability).
Description of drawings
Fig. 1 is the size changing rate of expression before and after the heat treatment, with the quality overall with respect to mixed-powder, and the plot of the relation of the mass ratio (containing ratios that particle diameter 45 μ m are following) of the mixed-powder of the sieve by mesh 45 μ m.
Embodiment
Present inventors, when implementing heat treatment by the resulting formed body of mixed-powder of the soft magnetic iron-based powder of insulating properties coating film and lubricant for being shaped, in order to suppress the expansion of this formed body, make the size changing rate of the formed body before and after the heat treatment be lower than 0.001% and research with keen determination repeatedly.It found that, if suitably adjust the particle size distribution of above-mentioned mixed-powder, then can reduce the size changing rate of the formed body that causes because of heat treatment, thereby finish the present invention.Below, describe for finishing fact of the present invention.
Among the compressed-core, for example as the compressed-core that is used for inductor, when excitation frequency is high frequency, decrease in order to reduce eddy current, what generally adopt is particle diameter little (for example, particle diameter is that 150 μ m are following) soft magnetic iron-based powder.In addition, as above-mentioned, the heating in order to prevent to be shaped is deadlocked, and in soft magnetic iron-based powder hybrid lubricant, this lubricant is usually with respect to the quality of soft magnetic iron-based powder and mix more than 0.5%.
If the formed body that obtains for the mixed-powder of be shaped such soft magnetic iron-based powder and lubricant is heat-treated, the situation that then has the size of situation that formed body expands after heat treatment and formed body not change or shrink.Distinguish when studying that the particle size distribution of the mixed-powder of soft magnetic iron-based powder and lubricant can impact the dimensional accuracy of heat treated formed body for its reason.Distinguish that promptly when containing the little micropowder of particle diameter in the mixed-powder in a large number, formed body expands after heat treatment.This be considered to because, if contain micropowder in a large number in the mixed-powder, then the pore that forms on formed body surface diminishes, the gas componant that takes place because of heat treatment is difficult to emit from formed body, formed body expands.Expand if form body through Overheating Treatment, then except the dimensional accuracy variation of formed body, the density of formed body also diminishes, so magnetic characteristic reduces.
Therefore present inventors further study for the particle size distribution and the relation of the size changing rate of the formed body of heat treatment front and back of above-mentioned mixed-powder.Its result as can be known, have in the mixed-powder of powder lubricant of insulating properties epithelium on the surface of containing soft magnetic iron-based powder, with respect to the overall quality of this mixed-powder, if the quality of the particle diameter mixed-powder that to be 106 μ m following is more than 95%, and particle diameter is that the quality of the following mixed-powder of 45 μ m (is not containing 0%) below 40%, the expansion of the formed body in the time of then can preventing heat treatment can be eliminated the change in size of the formed body of heat treatment front and back, or formed body is shunk.That is, in the present invention, be conceived to the phenomenon that lubricant volatilizees by heat treatment, distinguish, then can be suppressed to the expansion of body if make the lubricant external discharge of synform promptly of volatilization.
Also have, some expansions or contraction though do not change before and after being desirably in heat treatment, in fact, generally can take place in the size of formed body before and after heat treatment.If formed body expands, then as above-mentioned, because the density of formed body diminishes, so confirm the reduction of magnetic characteristic, but if formed body shrinks, then the density of formed body becomes greatly on the contrary, so magnetic characteristic can not reduce, and can increase on the contrary.Therefore in the present invention, suppressing the purpose that is expanded to of formed body that heat treatment causes, then be not considered as problem for the contraction of formed body.
Mixed-powder of the present invention, with respect to containing the powder that has the insulating properties epithelium on the surface of soft magnetic iron-based powder and the overall quality of mixed-powder of lubricant, particle diameter is that the mass ratio of the following mixed-powder of 106 μ m is more than 95%.Be suppressed at below 5% by the mass ratio that particle diameter is surpassed the thick mixed-powder of 106 μ m, can reduce eddy current and decrease.Particle diameter is that the mass ratio of the following mixed-powder of 106 μ m is preferably more than 97%, more preferably more than 98%.Also have, even use the sieve of mesh 106 μ m to sieve for mixed-powder, in fact the particle diameter thick powder that surpasses 106 μ m still has some and sneaks into, and most preferably is 100% but particle diameter is the mass ratio of the following mixed-powder of 106 μ m.
But overall quality with respect to mixed-powder, just controlling particle diameter is the mass ratio of the following mixed-powder of 106 μ m, can't suppress the expansion of the formed body that heat treatment causes, importantly overall with respect to above-mentioned mixed-powder quality, making particle diameter is that the mass ratio of the following mixed-powder of 45 μ m (is not containing 0%) below 40%.By reducing particle diameter is the mass ratio of the fine mixed-powder below the 45 μ m, use has the mixed-powder of particle diameter to a certain degree and is formed into body, when heat treatment, the formed body surface can form the to a certain degree pore of size, therefore the lubricant of volatilization is released to beyond the formed body easily, can prevent the expansion of the formed body that heat treatment causes.Particle diameter is that the mass ratio of the following mixed-powder of 45 μ m is preferably below 39%.Also have, particle diameter is that the lower limit of the mass ratio of the following mixed-powder of 45 μ m is not particularly limited, but is generally more than 30% degree.
Also have, in the present invention, so-called particle diameter is the following mixed-powders of 106 μ m, " the sieve analysis test method JPMAP02-1992 of metal powder " based on Japanese powder metallurgy industry meeting, it is mixed-powder by the sieve of mesh 106 μ m, so-called particle diameter is the following mixed-powders of 45 μ m, based on " the sieve analysis test method JPMAP02-1992 of metal powder " of Japanese powder metallurgy industry meeting, is the mixed-powder by the sieve of mesh 45 μ m.
Mixed-powder of the present invention contains the powder and the lubricant that have the insulating properties epithelium on the surface of soft magnetic iron-based powder.
Above-mentioned so-called soft magnetic iron-based powder is the iron-based powder of ferromagnetism body, specifically, can enumerate straight iron powder, iron(-)base powder (for example, Fe-Al alloy, Fe-Si alloy, sendust, permalloy etc.) and Fe-based amorphous powder etc.Above-mentioned soft magnetic iron-based powder can pass through for example atomization (gas atomization and water atomization) and comminuting method manufacturing.In addition, also can reduce for resulting powder as required.
Be formed with the insulating properties epithelium on the surface of above-mentioned soft magnetic iron-based powder.As above-mentioned insulating properties epithelium, for example, can enumerate inorganic epithelium of insulating properties and insulative resin epithelium.
As the inorganic epithelium of above-mentioned insulating properties, for example, can enumerate that phosphoric acid system changes into epithelium, chromium system changes into epithelium, waterglass epithelium, oxide epithelium etc., be preferably phosphoric acid system and change into epithelium.The inorganic epithelium of above-mentioned insulating properties also can stacked two or more epithelium and is formed, but is generally individual layer.
Surface at the inorganic epithelium of above-mentioned insulating properties preferably also forms the insulative resin epithelium.As above-mentioned insulative resin epithelium, for example, can enumerate silicones epithelium, phenolic resins epithelium, epoxy resin epithelium, polyamide epithelium, polyimide resin epithelium etc.Be preferably the silicones epithelium.Above-mentioned insulative resin epithelium also can stacked two or more epithelium and is formed, but is advisable with individual layer usually.
Also have, above-mentioned so-called insulating properties, in the present invention, the meaning is when measuring the resistivity of final compressed-core with four-terminal method, reach about 50 μ Ω m more than.
As above-mentioned lubricant, use always known getting final product, specifically, can enumerate the stearic metal salt powder of zinc stearate, lithium stearate, calcium stearate etc.; Port リ ヒ De ロ キ シ カ Le ボ Application acid ア ミ De), the fatty acid amide of ethylene bis stearic acid amide (ethylenebis (stearylamide): エ チ レ Application PVC ス ス テ ア リ Le ア ミ De) and the sour ア ミ of N-octadecylene base palmitamide ((N-octadecenyl) hexadecanoic acid amide:(N-オ Network タ デ セ ニ Le) ヘ キ サ デ カ Application De) etc. multi-hydroxy carboxy acid's acid amides (polyhydroxy carboxyl ic acid amide:; Paraffin, wax, natural or synthetic resin derivative etc.Wherein, preferred multi-hydroxy carboxy acid's acid amides and fatty acid amide.
Above-mentioned lubricant, preferably overall with respect to above-mentioned mixed-powder quality is 0.6～1% by quality ratio.If use above-mentioned mixed-powder of the present invention,, also can prevent the expansion of the formed body that causes because of heat treatment even then the mass ratio of above-mentioned lubricant is more than 0.6%.The mass ratio of above-mentioned lubricant is more preferably more than 0.7%.But above-mentioned lubricant blending surpasses 1%, and its effect is saturated, if the amount of lubricant is many, then the density of formed body diminishes, the magnetic characteristic deterioration in addition.Therefore, the mass ratio of above-mentioned lubricant is preferably below 1%, more preferably below 0.9%.
Mixed-powder of the present invention can use when making compressed-core, for example, as the compressed-core of outer iron shape, is making complex-shapedly, makes in a large number with lubricator and also can be fit to use when making compressed-core.This compressed-core for example can use as the constituent part of the electromagnetic component of inductor etc.As inductor, but illustration reactor, noise filter, transformer, choke etc.
Secondly, describe for the method for using mixed-powder of the present invention to make compressed-core.Above-mentioned compressed-core can be made by using extruder and the metal die above-mentioned mixed-powder that is shaped.Mixed-powder, as above-mentioned, be to contain to have the powder of insulating properties epithelium and the compressed-core mixed-powder of lubricant on the surface of soft magnetic iron-based powder, below, describe for the method for using compressed-core to make compressed-core particularly with mixed-powder, this compressed-core contains as follows with mixed-powder: on the surface of soft magnetic iron-based powder, have phosphoric acid system as the inorganic epithelium of insulating properties and change into epithelium, this external its surface also has the powder of silicones epithelium as the insulative resin epithelium; Lubricant.
Also have, below, for convenience, have the surface at above-mentioned soft magnetic iron-based powder is formed with the powder that phosphoric acid system changes into epithelium, only be called the situation of " phosphoric acid system changes into epithelium and forms powder ".In addition,, have, only be called the situation of " the silicones epithelium forms powder " being to change into the powder that also is formed with the silicones epithelium on the epithelium at above-mentioned phosphoric acid for method.
At first, inductor (particularly reactor) etc. are with the electromagnetic component of high-frequency drive, and as above-mentioned soft magnetic iron-based powder, preferably using average grain diameter is the following powder of 100 μ m, more preferably below the 75 μ m.
Secondly, on the surface of this soft magnetic iron-based powder, form phosphoric acid system in order and change into epithelium and silicones epithelium.Below, change into epithelium and the silicones epithelium describes for phosphoric acid system.
＜phosphoric acid system changes into epithelium 〉
Phosphoric acid system changes into epithelium, so long as use the glass epithelium of the compound formation that contains P, then its composition is not particularly limited, above-mentioned phosphoric acid is to change into epithelium, except P, also can contain one or more the element of selecting among Ni, Co, Na, K, S, Si, B, the Mg etc.These elements have and suppress that oxygen forms semiconductor with Fe and the effect that makes the resistivity reduction when carrying out heat treatment step described later.
Above-mentioned phosphoric acid is that the thickness that changes into epithelium is preferably about 1～250nm.If Film Thickness Ratio 1nm is thin, then insulation effect can't embody.If thickness surpasses 250nm, then insulation effect is saturated in addition, and also is not preferred from the densification this point of compressed-core.Preferred thickness is 10～50nm.
＜phosphoric acid system changes into the formation method of epithelium 〉
The phosphoric acid system that uses among the present invention changes into epithelium and forms powder, can with which kind of form manufacturing.For example, can in the solvent that constitutes by water and/or organic solvent, have after the solution and soft magnetic iron-based powder that contains P-compound by mixed dissolution, make described solvent evaporation as required and obtain.As the employed solvent of this operation, can enumerate the hydrophilic organic solvent of water, pure and mild ketone etc., and their mixture.Also can add known surfactant in the solvent.As the above-mentioned compound that contains P, can enumerate for example orthophosphoric acid (H
3PO
4) or its salt etc.
In addition also can be as required, after above-mentioned mixed processes, in atmosphere, under the decompression or under the vacuum, carry out drying with 150～250 ℃.After the drying, also can make it by the sieve about mesh 200～500 μ m.Through above-mentioned operation, can access and be formed with phosphoric acid system that phosphoric acid system changes into epithelium and change into epithelium and form powder.
＜silicones epithelium 〉
In the present invention, be to change on the epithelium at above-mentioned phosphoric acid, also can also have the silicones epithelium.Thus, when the crosslinked/cured reaction of silicones finishes (during compression), combination securely between the powder.In addition, form the Si-O key of excellent heat resistance, can improve the thermal stability of insulating coating.The thickness of above-mentioned silicones epithelium is preferably 1～200nm, more preferably 20～150nm.In addition, above-mentioned phosphoric acid is that the aggregate thickness that changes into epithelium and above-mentioned silicones epithelium is preferably below the 250nm.If thickness surpasses 250nm, then there is the reduction of magnetic flux density to become big situation.
The formation method of＜silicones epithelium 〉
The formation of above-mentioned silicones epithelium, for example, can carry out in the following way: mix the oil make silicones be dissolved in alcohols, toluene, dimethylbenzene etc. and be the silicon resin solution in the organic solvent etc., with having phosphoric acid is the soft magnetic iron-based powder (phosphoric acid system changes into epithelium and forms powder) that changes into epithelium, then makes described organic solvent evaporation as required.
Then, will be on the surface of soft magnetic iron-based powder, being formed with phosphoric acid in order is that insulating coating lining soft magnetic iron-based powder and the lubricant that changes into epithelium and silicones epithelium mixes the modulation mixed-powder.Under the effect of lubricant, between the powder in the time of can reducing the shaping soft magnetic iron-based powder, or the friction impedance between powder and shaping dies inwall, can prevent the sticking to mould of compressed-core and the heat release when being shaped.
Based on " the sieve analysis test method JPMAP02-1992 of metal powder " of Japanese powder metallurgy industry meeting, use the sieve of mesh 106 μ m, sieve for resulting mixed-powder, reclaim mixed-powder by sieve.
Then, the above-mentioned mixed-powder of shaping (press molding) screening and recovery is made compressed-core.Manufacturing process is not particularly limited, and can adopt known method always.The suitable condition that is shaped is that face is pressed 490～1960MPa.Forming temperature is that room temperature is shaped, warm working (100～250 ℃) all can.
Then, in the present invention, implement heat treatment (heat treatment step) for the formed body after being shaped.The strain that is imported into when being shaped obtains discharging thus, can reduce the magnetic hysteresis of compressed-core and decrease.At this moment heat treatment temperature is preferably more than 400 ℃, more preferably more than 450 ℃, more preferably more than 500 ℃.If this operation does not make the resistivity deterioration, then preferably carry out with higher temperature.But if heat treatment temperature surpasses 700 ℃, then insulating coating can be destroyed.Therefore heat treatment temperature is preferably below 700 ℃, more preferably below 650 ℃.
Atmosphere during above-mentioned heat treatment is non-oxidizing atmosphere.As atmosphere gas, can enumerate the rare gas of nitrogen or helium and argon etc. etc.In addition, also can under vacuum, heat-treat.Heat treatment time only otherwise the resistivity deterioration just is not particularly limited is preferably more than 20 minutes, more preferably more than 30 minutes, more preferably more than 1 hour.
If heat-treat with above-mentioned condition, then can not make eddy current decrease (being equivalent to coercive force) increase, have high electric insulation and can produce, i.e. the compressed-core of high resistivity.
Compressed-core of the present invention can cool off after heat treated above-mentioned, is returned to normal temperature and obtains.
[embodiment]
Below, enumerate embodiment and be described more specifically the present invention, but the present invention not being limited by following embodiment certainly, can certainly suitably be changed enforcement in the scope that can meet the front/rear aim of stating, these all are included in the scope of technology of the present invention.Also have, unless otherwise indicated, otherwise " part " meaning is " mass parts ", and " % " meaning is " quality % ".
As soft magnetic iron-based powder, prepare straight iron powder (Kobe Steel made " ア ト メ Le (registered trade mark) 300NH ") 10 kinds, " the sieve analysis test method JPMAP02-1992 of metal powder " based on Japanese powder metallurgy industry meeting, use the sieve of mesh 75 μ m respectively it to be sieved, use the powder that has passed through sieve.
On the surface of resulting soft magnetic iron-based powder,, form inorganic epithelium of insulating properties and insulative resin epithelium in order as the insulating properties epithelium.
Form phosphoric acid system as the inorganic epithelium of insulating properties and change into epithelium, form the silicones epithelium as the insulative resin epithelium.
System changes in the formation of epithelium at phosphoric acid, and system changes into the epithelium treatment fluid as phosphoric acid, uses following treatment fluid, that is, mixing water: 50 parts, NaH
2PO
4: 30 parts, H
3PO
4: 10 parts, (NH
2OH)
2H
2SO
4: 10 parts, Co
3(PO
4)
2: 10 parts, be diluted with water to 20 times again.The thickness that phosphoric acid system changes into epithelium is 10～100nm.
In the formation of silicones epithelium, using silicones " SR2400 " (eastern Li Daokangningshe system) is dissolved in that toluene is modulated, resin solid content concentration is 5% resin solution.The thickness of silicones epithelium is 100～500nm.
The soft magnetic iron-based powder (below, be called insulating coating lining soft magnetic iron-based powder) and the lubricant that will be formed with insulating coating are mixed manufacturing compressed-core mixed-powder.
As lubricant, use the ethylene bis stearic acid amide (" WXDBS (trade name) ", formal name: N, N '-ethylene bis stearic acid amide, fusing point: 143 ℃) of big day chemical society system.The granularity of lubricant, with respect to the overall quality of lubricant, the ratio of the quality of the lubricant of the sieve by mesh 45 μ m is more than 90%, the about 10 μ m of average grain diameter.Above-mentioned lubricant mixes with the ratio of 0.8g with respect to above-mentioned insulating coating lining soft magnetic iron-based powder 100g.
Based on " the sieve analysis test method JPMAP02-1992 of metal powder " of Japanese powder metallurgy industry meeting, use the sieve of mesh 106 μ m, sieve with mixed-powder for resulting compressed-core, reclaim the mixed-powder that has passed through sieve.Use the sieve of mesh 180 μ m, mesh 150 μ m, mesh 106 μ m, mesh 75 μ m, mesh 63 μ m and mesh 45 μ m, sieve, implement classification and measure particle size distribution for the mixed-powder that reclaims.The particle size distribution of measuring is presented in the following table 1.In following table 1, also show the quality overall with respect to mixed-powder, passed through the ratio (particle diameter is the following total quality of 106 μ m) of quality of mixed-powder of the sieve of mesh 106 μ m.
Then, using extruder, under room temperature (25 ℃), is 785MPa (8ton/cm with the face pressure
2) mode, form with mixed-powder for resulting compressed-core and manufacture body.Formed body be shaped as the tabular of wide 12.7mm * long 31.75mm * thick 5mm.
For resulting tabular formed body, under blanket of nitrogen,, remove strain annealing with 520 ℃ of heat treatments of implementing 30 minutes.Also have, about 10 ℃/minute of the programming rate when room temperature is heated to 520 ℃, it is cold to carry out stove after the heat treatment.
After the heat treatment, at the width of the center position measurement formed body of length direction, based on the width of the formed body of before heat treatment, measuring, according to following formula driven dimension rate of change (%).The size changing rate that calculates is presented in the following table 1.In the present invention, it is qualified that size changing rate is lower than 0.001% situation, and size changing rate is defective in the situation more than 0.001%.When size changing rate is negative value, mean that formed body shrinks through heat treatment, size changing rate be on the occasion of the time, mean that formed body expands through heat treatment.
Size changing rate (%)=[width of the formed body after (width of the formed body before the width-heat treatment of the formed body after the heat treatment)/heat treatment] * 100
In addition, the size changing rate before and after the heat treatment is presented among Fig. 1 with the relation of the mass ratio (containing ratios that particle diameter 45 μ m are following) of the mixed-powder of the sieve that has passed through mesh 45 μ m with respect to the overall quality of mixed-powder.
Can carry out following investigation by following table 1 and Fig. 1.The example of the important document of the present invention regulation is satisfied in No.1～7th, and the particle size distribution of the mixed-powder of insulating coating lining soft magnetic iron-based powder and lubricant satisfies defined terms.Therefore as can be known,, implement heat treatment, then can reduce the size changing rate of the formed body of heat treatment front and back if use this mixed-powder to manufacture body.No.6,7 particularly, the size changing rate of the formed body before and after the heat treatment is 0%.Therefore if use mixed-powder of the present invention, then the size changing rate of formed body is little, can improve the density of formed body, thinks the magnetic characteristic that can improve compressed-core.
On the other hand, No.8～10th, the example of the important document of discontented unabridged version invention regulation, the particle size distribution of the mixed-powder of insulating coating lining soft magnetic iron-based powder and lubricant does not satisfy defined terms.Therefore,, implement heat treatment if use this mixed-powder to manufacture body, then the size changing rate of the formed body before and after the heat treatment be on the occasion of, heat treatment causes the formed body expansion as can be known.Therefore if use these mixed-powders, then therefore the density step-down of formed body thinks that the magnetic characteristic of compressed-core reduces.
As above as can be known, the particle size distribution of the mixed-powder of insulating coating lining soft magnetic iron-based powder and lubricant is by satisfying defined terms, and the size changing rate of the formed body before and after the heat treatment diminishes.Therefore think, implement heat treatment and the magnetic characteristic of the compressed-core that obtains improves.
Table 1
Claims (9)
1. a compressed-core mixed-powder is characterized in that, be to contain on the surface of soft magnetic iron-based powder to have the powder of insulating properties epithelium and the compressed-core mixed-powder of lubricant, wherein,
With respect to the overall quality of described mixed-powder, particle diameter be the mass ratio of the following mixed-powder of 106 μ m more than 95%, and particle diameter is that the mass ratio of the following mixed-powder of 45 μ m is below 40% but do not contain 0%.
2. compressed-core mixed-powder according to claim 1, wherein, with respect to the overall quality of described mixed-powder, the mass ratio of described lubricant is 0.6～1%.
3. compressed-core mixed-powder according to claim 1 wherein, is formed with the inorganic epithelium of insulating properties as described insulating properties epithelium.
4. compressed-core mixed-powder according to claim 3 wherein, also is formed with the insulative resin epithelium on the surface of the inorganic epithelium of described insulating properties.
5. according to each described compressed-core mixed-powder in the claim 1～4, it is used to the manufacturing of the magnetic core of inductor.
6. a compressed-core is characterized in that, each described compressed-core obtains with mixed-powder in the use claim 1～4.
7. the manufacture method of a compressed-core is characterized in that, each described compressed-core in the claim 1～4 is formed with mixed-powder.
8. the manufacture method of compressed-core according to claim 7 wherein, after shaping, is being heat-treated formed body more than 400 ℃ in non-oxidizing atmosphere.
9. the manufacture method of compressed-core according to claim 7, wherein, described compressed-core is the magnetic core of inductor.
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| JP2012017711A JP5814809B2 (en) | 2012-01-31 | 2012-01-31 | Powder mixture for dust core |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105161239A (en) * | 2015-09-16 | 2015-12-16 | 广州齐达材料科技有限公司 | Composite half-hard magnetic material and preparation method thereof |
| CN112912976A (en) * | 2018-10-30 | 2021-06-04 | 阿尔卑斯阿尔派株式会社 | Powder molded core, method for producing powder molded core, inductor provided with powder molded core, and electronic/electrical device equipped with inductor |
| CN113543908A (en) * | 2019-03-22 | 2021-10-22 | 日本特殊陶业株式会社 | Dust core |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP7441113B2 (en) | 2019-08-02 | 2024-02-29 | 国立大学法人東海国立大学機構 | powder magnetic core |
| CN111974987B (en) * | 2020-08-14 | 2022-09-13 | 泉州天智合金材料科技有限公司 | Insulating coating layer of Fe-based soft magnetic powder and coating method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1122527A (en) * | 1994-07-22 | 1996-05-15 | Tdk株式会社 | Iron core of pressed powder |
| JP2006283166A (en) * | 2005-04-04 | 2006-10-19 | Jfe Steel Kk | Coated iron based powder for powder magnetic core, and powder magnetic core |
| CN101511511A (en) * | 2006-09-11 | 2009-08-19 | 株式会社神户制钢所 | Powder magnetic core and iron-base powder for powder magnetic core |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0464441A (en) * | 1990-07-04 | 1992-02-28 | Achilles Corp | Ionomer multilayer seat material |
| JPH06120046A (en) * | 1992-09-25 | 1994-04-28 | Tokin Corp | Dust core |
| JP2001358005A (en) | 2000-06-13 | 2001-12-26 | Daido Steel Co Ltd | Atomized soft magnetic powder and dust core using it |
| JP2003224017A (en) * | 2002-01-28 | 2003-08-08 | Kobe Steel Ltd | Powder magnetic core and method of manufacturing the same |
| JP2003332116A (en) | 2002-05-15 | 2003-11-21 | Hitachi Powdered Metals Co Ltd | Dust core and its manufacturing method |
| JP4134111B2 (en) * | 2005-07-01 | 2008-08-13 | 三菱製鋼株式会社 | Method for producing insulating soft magnetic metal powder compact |
| JP4044591B1 (en) * | 2006-09-11 | 2008-02-06 | 株式会社神戸製鋼所 | Iron-based soft magnetic powder for dust core, method for producing the same, and dust core |
| JP2008248306A (en) * | 2007-03-30 | 2008-10-16 | Daido Steel Co Ltd | Powder for powder compaction, powder-compacted magnetic core, and method for producing the same |
| JP5022999B2 (en) * | 2008-06-17 | 2012-09-12 | 株式会社タムラ製作所 | Powder magnetic core and manufacturing method thereof |
| JP2010272604A (en) * | 2009-05-20 | 2010-12-02 | Nec Tokin Corp | Soft magnetic powder and dust core using the same, and inductor and method of manufacturing the same |
-
2012
- 2012-01-31 JP JP2012017711A patent/JP5814809B2/en active Active
-
2013
- 2013-01-09 TW TW102100698A patent/TWI478184B/en active
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1122527A (en) * | 1994-07-22 | 1996-05-15 | Tdk株式会社 | Iron core of pressed powder |
| JP2006283166A (en) * | 2005-04-04 | 2006-10-19 | Jfe Steel Kk | Coated iron based powder for powder magnetic core, and powder magnetic core |
| CN101511511A (en) * | 2006-09-11 | 2009-08-19 | 株式会社神户制钢所 | Powder magnetic core and iron-base powder for powder magnetic core |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105161239A (en) * | 2015-09-16 | 2015-12-16 | 广州齐达材料科技有限公司 | Composite half-hard magnetic material and preparation method thereof |
| CN105161239B (en) * | 2015-09-16 | 2018-08-24 | 广州齐达材料科技有限公司 | A kind of compound half-hard magnetic material and preparation method thereof |
| CN112912976A (en) * | 2018-10-30 | 2021-06-04 | 阿尔卑斯阿尔派株式会社 | Powder molded core, method for producing powder molded core, inductor provided with powder molded core, and electronic/electrical device equipped with inductor |
| CN112912976B (en) * | 2018-10-30 | 2024-01-12 | 阿尔卑斯阿尔派株式会社 | Powder compact core, method for manufacturing the same, inductor provided with the same, and electronic/electrical device provided with the inductor |
| CN113543908A (en) * | 2019-03-22 | 2021-10-22 | 日本特殊陶业株式会社 | Dust core |
| CN113543908B (en) * | 2019-03-22 | 2023-05-23 | 日本特殊陶业株式会社 | Powder magnetic core |
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| JP2013155414A (en) | 2013-08-15 |
| TWI478184B (en) | 2015-03-21 |
| TW201346946A (en) | 2013-11-16 |
| KR20130088801A (en) | 2013-08-08 |
| KR101436720B1 (en) | 2014-09-01 |
| CN103227020B (en) | 2016-04-27 |
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