CN104084586A - Filter-pressing preparation method for soft-magnetic composite material - Google Patents
Filter-pressing preparation method for soft-magnetic composite material Download PDFInfo
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- CN104084586A CN104084586A CN201410247670.3A CN201410247670A CN104084586A CN 104084586 A CN104084586 A CN 104084586A CN 201410247670 A CN201410247670 A CN 201410247670A CN 104084586 A CN104084586 A CN 104084586A
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Abstract
The invention discloses a filter-pressing molding preparation method for a soft-magnetic composite material. The method comprises the steps of 1) preparing a multiporous die; 2) preparing soft-magnetic powder; 3) screening the soft-magnetic powder, and detecting the performance of the soft-magnetic powder; 4) performing passivation treatment on the soft-magnetic powder; 5) mixing the soft-magnetic powder with water or an organic solvent, adding an adhesive, stirring to prepare uniformly distributed slurry, and performing pouring; 6) performing filter-pressing molding on the slurry obtained in the step 5); 7) performing drying and sintering molding. The method disclosed by the invention has the advantages that by the adoption of the filter-pressing method instead of non-conventional direct dry powder pressing molding, required equipment is simple, the working procedures are simplified, and the cost is lowered; furthermore, the prepared soft-magnetic composite material is higher in uniformity.
Description
Technical field
The present invention relates to field of magnetic material, relate in particular to a kind of preparation method to the lower soft-magnetic composite material of pressing pressure requirement.
Background technology
Soft-magnetic composite material is a kind of conventional functional material, because it has good medium-high frequency soft magnet performance and lower loss, has obtained research widely and application in fields such as electron and electricians.Conventional soft-magnetic composite material mainly contains ferrocart core, iron silica flour core sendust powder core, Hi-Fiux powder core, MPP powder core and amorphous core in recent years, nanometer crystal powder core etc. at present.Existing powder core product has feature separately in performance, and price variance is very large, and application is also had nothing in common with each other.
The processing step that the preparation method of metal current powder core mainly takes is 1. powder preparations, 2. powder sieving, and 3. Passivation Treatment, 4. mixes with megohmite insulant, 5. compressing, 6. annealing in process.In this technique, because the adhesive property between metal dust is poor, therefore need a very large pressure just can make metal dust compressing, therefore need to produce the press device of larger pressure, the hydraulic test of current industrial multi-functional large, pressure often requires more than 1.5GPa, and equipment requirement is higher; Meanwhile, because pressure is larger, the passivating film that causes powder particle surface passivation before to produce is easily broken, causes passivation incomplete, thereby the effective resistivity of powder core is reduced, and produces larger eddy-current loss under high frequency condition.On the other hand, when direct pressing powder core, be dry powder later due to what adopt, the mobility between particle is poor, easily causes the magnetic-particle skewness of the powder core of compacting, thereby affects the soft magnet performance of powder core.
Summary of the invention
The object of the invention is, for above-mentioned phenomenon, provides a kind of preparation method of pressure filtration molding of soft-magnetic composite material.
The preparation method's of the pressure filtration molding of soft-magnetic composite material step is as follows:
1) prepare porous mold
α-gypsum and β-gypsum mix with water, stir 2～10min and obtain calcium plaster, by calcium plaster solidify, hardening makes gypsum mold, in the environment that to be kept at 25～40 DEG C, relative humidity after dry be 20～40%, the mass ratio of described α-gypsum and β-gypsum is 2:1～1:2;
2) choose and sieve soft magnetic powder;
3) soft magnetic powder is carried out to insulating wrapped
Adopt phosphoric acid, nitric acid, chromic acid, phosphate, magnesia, silica or aluminium oxide to carry out insulating wrapped to soft magnetic powder;
4) slurry preparation
The soft magnetic powder that is 0.1～100 μ m by particle size adds in water or organic solvent, and making solid concentration is 40vol%～45vol%, stirs, and ultrasonic dispersion is processed 1～20min, obtains finely dispersed slurry;
5) slurries are carried out to pressure filtration molding
Slurry is placed in to gypsum mold, and under the pressure of 0.1～15Mpa, 10～120min is processed in pressurize;
6) sintering
Slurry curing after press filtration is removed to mould, and slowly dry at 35～60 DEG C, be placed in punching block, under the pressure of 0.2～1Gpa, suppress sinter molding under the protection of nitrogen or argon gas.
Described soft magnetic powder is one or more in iron powder, iron silica flour, iron aluminum silicon powder, Fe-based amorphous powder, iron based nano crystal powder, iron nickel powder and iron nickel molybdenum powder.
Described binding agent is selected from respectively polyvinyl fluoride, melmac, phenolic resins, epoxy resin or silicone resin.
Described step 4) in organic solvent be ethanol, acetone or dimethylbenzene.
Filter-pressing process is the forming ceramic parts technique of extensive use in recent years, its principle is outside under pressure-acting, make the slurry that is dispersed with solid phase ceramic particle in liquid medium enter model inside by feed pipe for mortar, and leach operative liquid medium by porous filtering layer, make ceramic particle close-packed arrays be solidified into the effigurate ceramic idiosome of tool.Because pressure filtration molding adopts a small amount of organic binder bond, compact density is high, owing to adopting porous mold, is conducive to organic discharge, can not cause organic matter to be mingled with the defect causing.Pressure filtration molding adopts liquid phase medium to prepare slurry directly-forming, can adopt the methods such as precipitate and separate remove aggregate, the bulky grain in powder and be mingled with body.And drying straight forming has not been avoided new formation of the agglomerates, thereby improve the micro-uniformity of moulding idiosome.
Therefore, adopt filter press technique to prepare soft-magnetic composite material, not only can reduce the pressure when compressing, thereby reduce the requirement of production equipment, can also make the powder core uniformity of preparation better, be conducive to the further raising of soft-magnetic composite material magnetic property.
Detailed description of the invention
Soft-magnetic composite material of the present invention be by one or more soft magnetic powders as iron powder, iron silica flour, iron aluminum silicon powder, Fe-based amorphous powder, iron based nano crystal powder, iron nickel powder and iron nickel molybdenum powder and deionized water composition slurry, pour into dies cavity, carry out pressure filtration molding.The stock obtaining is made soft-magnetic composite material after curing, sintering.
The preparation method's of the pressure filtration molding of soft-magnetic composite material step is as follows:
1) prepare porous mold
α-gypsum and β-gypsum mix with the water of 15～25 DEG C, stir 2～10min and obtain calcium plaster, by calcium plaster solidify, hardening makes gypsum mold, in the environment that to be kept at 25～40 DEG C, relative humidity after dry be 20～40%, the mass ratio of described α-gypsum and β-gypsum is 2:1～1:2;
2) choose and sieve soft magnetic powder;
3) soft magnetic powder is carried out to insulating wrapped
Adopt phosphoric acid, nitric acid, chromic acid, phosphate, magnesia, silica or aluminium oxide to carry out insulating wrapped to soft magnetic powder;
4) slurry preparation
The soft magnetic powder that is 0.1～100 μ m by particle size adds in water or organic solvent, and making solid concentration is 40vol%～45vol%, stirs, and ultrasonic dispersion is processed 1～20min, obtains finely dispersed slurry;
5) slurries are carried out to pressure filtration molding
Slurry is placed in to gypsum mold, and under the pressure of 0.1～15Mpa, 10～120min is processed in pressurize;
6) sintering
Slurry curing after press filtration is removed to mould, and slowly dry at 35～60 DEG C, be placed in punching block, under the pressure of 0.2～1Gpa, suppress sinter molding under the protection of nitrogen or argon gas.
Described soft magnetic powder is one or more in iron powder, iron silica flour, iron aluminum silicon powder, Fe-based amorphous powder, iron based nano crystal powder, iron nickel powder and iron nickel molybdenum powder.Described binding agent is selected from respectively polyvinyl fluoride, melmac, phenolic resins, epoxy resin or silicone resin.
Described step 4) in organic solvent be ethanol, acetone or dimethylbenzene.
Below in conjunction with example, the present invention is described in further detail:
Embodiment 1:
α-the gypsum that is 2:1 with mass ratio and β-gypsum mix with water, and add 10wt% phenolic resins, stir 4min, build, after calcium plaster is solidified, hardens, is dried, make the circular mould that mould inside die cavity is external diameter 23.6mm internal diameter 14.4mm height 8.89mm.
After mixing, add the phosphoric acid of iron-silicon-aluminum soft magnetic powder weight 2% to carry out insulating wrapped 10wt%100 order～200 order, 80wt%200 order～400 order, 10wt%-400 object iron-silicon-aluminum soft magnetic powder.
Powder after insulating wrapped is added to deionized water, and solid concentration reaches 45vol%, fully stirs 4h, and adopts ultrasonic wave to carry out dispersion processing, obtains building slurry, and slurry is injected to gypsum mold, the 0.1MPa that exerts pressure, and pressurize 120min.
Idiosome after solidifying is dried and is placed in punching block at the temperature of 40 DEG C, under the pressure of 1GPa, suppresses, and under argon shield, under 600 DEG C of conditions, is incubated 0.5h, air cooling, and spraying, obtains sendust powder core.
After testing, the associated electrical magnetic parameter of target product is as follows:
Embodiment 2:
α-the gypsum that is 1:1 with mass ratio and β-gypsum mix with water, and add 10wt% polyvinyl fluoride, stir 4min, build, after calcium plaster is solidified, hardens, is dried, make the circular mould that mould inside die cavity is external diameter 23.6mm internal diameter 14.4mm height 8.89mm.
Be Fe17wt% by composition ratio, Ni79wt%, Mo2wt%, Cu1wt%, Al, Si<1wt% size are that 10%100 order～200 orders, 80%200 order～400 orders, 10%-400 object iron nickel molybdenum soft magnetic powder mix the rear chromic acid solution with 1wt% and carry out insulating wrapped.
Powder after insulating wrapped is added to absolute ethyl alcohol, reach 45vol% to solid concentration, fully stir 6h, and adopt ultrasonic wave to carry out dispersion processing, obtain building slurry, slurry is injected to gypsum mold, the 5MPa that exerts pressure, and pressurize 40min.
Idiosome after solidifying is dried and is placed in punching block at the temperature of 40 DEG C, under the pressure of 1GPa, suppresses, and under argon shield, under 690 DEG C of conditions, is incubated 1h, air cooling, and spraying, obtains iron nickel-molybdenum alloy powder core.
After testing, the associated electrical magnetic parameter of target product is as follows:
Embodiment 3:
α-the gypsum that is 1:2 with mass ratio and β-gypsum mix with water, and add 10wt% epoxy resin, stir 4min, build, and after calcium plaster is solidified, is dried, make the circular mould that mould inside die cavity is external diameter 23.6mm internal diameter 14.4mm height 8.89mm.
Be Fe by composition
90si
2b
4cu
1p
2y
1size is that 15%100 order～200 orders, 70%200 order～300 orders, 15%300 order～400 object nano-crystal soft-magnetic powder mix the rear magnesia with 0.4wt% and carry out insulating wrapped.
Powder after insulating wrapped is added to acetone solvent, reach 40vol% to solid concentration, fully stir 4h, and adopt ultrasonic wave to carry out dispersion processing, obtain building slurry, slurry is injected to gypsum mold, the 0.6MPa that exerts pressure, and pressurize 80min.
Idiosome after solidifying is dried and is placed in punching block at the temperature of 35 DEG C, under the pressure of 0.5GPa, suppresses, and under argon shield, under 500 DEG C of conditions, is incubated 1h, air cooling, and spraying, obtains nanocrystalline alloy magnetic powder core.
After testing, the associated electrical magnetic parameter of target product is as follows:
Embodiment 4:
α-the gypsum that is 1:1 with mass ratio and β-gypsum mix with water, and add gypsum quality 10% melmac, stir 4min, build, after calcium plaster is solidified, hardens, is dried, make the circular mould that mould inside die cavity is external diameter 23.6mm internal diameter 14.4mm height 8.89mm.
Be Si6.4wt% by composition, V0.4wt%, Nb0.2wt%, all the other are-200 orders for Fe is big or small: the iron silicon soft magnetic powder of-100 orders :-60 orders=3:3:1 mixes the rear ferric phosphate with 30wt% and carries out insulating wrapped.
Mixed-powder is added to dimethyl benzene, reach 40vol% to solid concentration, fully stir 5h, and adopt ultrasonic wave to carry out dispersion processing, obtain building slurry, slurry is injected to gypsum mold, the 0.6MPa that exerts pressure, and pressurize 80min.
Idiosome after solidifying is dried and is placed in punching block at the temperature of 60 DEG C, under the pressure of 0.2GPa, suppresses, and under argon shield, under 720 DEG C of conditions, is incubated 1h, air cooling, and spraying, obtains ferrum-silicon alloy magnetic powder core.
After testing, the associated electrical magnetic parameter of target product is as follows:
Embodiment 5:
Mix with the water of 20 DEG C with α-gypsum and β-gypsum, and add 10wt% melmac to stir 4min, build, calcium plaster is solidified, harden, makes mould inside die cavity after dry is the highly circular mould of 8.89mm of external diameter 23.6mm internal diameter 14.4mm.
Be Fe by composition
78si
9b
13granular size is-100 orders～+ 200 order :-200 orders～+ 270 order: the amorphous soft magnet powder of-270 orders～+ 325 orders=1:4:5 mixes the rear phosphoric acid with 5w% and carries out insulating wrapped.
Mixed-powder is added in deionized water, reach 40vol% to solid concentration, fully stir 3h, and adopt ultrasonic wave to carry out dispersion processing, obtain building slurry, slurry is injected to gypsum mold, the 2MPa that exerts pressure, and pressurize 20min
Idiosome after solidifying is dried and is placed in punching block at the temperature of 40 DEG C, under the pressure of 0.6GPa, suppresses, and under argon shield, under 440 DEG C of conditions, is incubated 3h, air cooling, and spraying, obtains non-crystaline amorphous metal powder core.
After testing, the associated electrical magnetic parameter of target product is as follows:
Claims (4)
1. a preparation method for the pressure filtration molding of soft-magnetic composite material, is characterized in that its step is as follows:
1) α-gypsum and β-gypsum mix with water, and add the binding agent of gypsum gross mass 10%, stir 2min～10min and obtain calcium plaster, by calcium plaster solidify, hardening makes gypsum mold, in the environment that to be kept at 25 DEG C～40 DEG C, relative humidity after dry be 20%～40%, the mass ratio of described α-gypsum and β-gypsum is 2:1～1:2;
2) adopt phosphoric acid, nitric acid, chromic acid, phosphate, magnesia, silica or aluminium oxide to carry out insulating wrapped to soft magnetic powder;
3) by step 2) soft magnetic powder after insulating wrapped adds in water or organic solvent, and making solid concentration is 40vol%～45vol%, stirs, and ultrasonic dispersion is processed 1min～20min, obtains finely dispersed slurry;
4) slurry is placed in to gypsum mold, under the pressure of 0.1Mpa～15Mpa, 10min～120min is processed in pressurize;
5) slurry curing after press filtration is removed to mould, and slowly dry at 35～60 DEG C, be placed in punching block, under the pressure of 0.2～1Gpa, suppress sinter molding under the protection of nitrogen or argon gas.
2. the preparation method of the pressure filtration molding of a kind of soft-magnetic composite material according to claim 1, is characterized in that described soft magnetic powder is one or more in iron powder, iron silica flour, iron aluminum silicon powder, Fe-based amorphous powder, iron based nano crystal powder, iron nickel powder and iron nickel molybdenum powder.
3. the preparation method of the pressure filtration molding of a kind of soft-magnetic composite material according to claim 1, is characterized in that described binding agent is selected from respectively polyvinyl fluoride, melmac, phenolic resins, epoxy resin or silicone resin.
4. the preparation method of the pressure filtration molding of a kind of soft-magnetic composite material according to claim 1, is characterized in that described step 4) in organic solvent be ethanol, acetone or dimethylbenzene.
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Cited By (4)
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| CN107610871A (en) * | 2017-10-31 | 2018-01-19 | 国网江苏省电力公司电力科学研究院 | A kind of preparation method of low-loss iron silicon metal soft magnetic powder core towards large power reactor |
| CN109317689A (en) * | 2018-11-01 | 2019-02-12 | 江西理工大学 | A kind of permalloy magnetic Nano absorbing material of core-shell structure and preparation method thereof |
| CN111266571A (en) * | 2020-02-26 | 2020-06-12 | 北京科技大学 | Adhesive, TiAl alloy turbine injection molding preparation method and product |
| CN114576935A (en) * | 2022-04-29 | 2022-06-03 | 合肥八维七度新材料科技有限公司 | Metal powder cold pressing equipment with pressure drop eliminating function |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109317689B (en) * | 2018-11-01 | 2021-11-23 | 江西理工大学 | Permalloy magnetic nano wave-absorbing material with core-shell structure and preparation method thereof |
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