CN101824512A - Electromagnet type transverse magnetic field heat treatment equipment and method for preparing permanent magnet iron corepermanent magnet - Google Patents
Electromagnet type transverse magnetic field heat treatment equipment and method for preparing permanent magnet iron corepermanent magnet Download PDFInfo
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- CN101824512A CN101824512A CN 201010179832 CN201010179832A CN101824512A CN 101824512 A CN101824512 A CN 101824512A CN 201010179832 CN201010179832 CN 201010179832 CN 201010179832 A CN201010179832 A CN 201010179832A CN 101824512 A CN101824512 A CN 101824512A
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Abstract
The invention discloses electromagnet type transverse magnetic field heat treatment equipment comprising a heating furnace and an electromagnet, wherein the magnetic field direction generated by the electromagnet is parallel to the vertical direction of the heating furnace; the heating furnace comprises a furnace casing and a hearth formed by the furnace casing; and a heating element is arranged at the inner side of a furnace wall. In the process of preparing a permanent magnet iron core by using the equipment, an iron core to be treated is placed in the hearth of the transverse magnetic field heat treatment equipment; the temperature in the hearth is adjusted in the range of +/-10 DEG C of the Curie temperature of the iron core to be treated by using the heating element; a magnetic filed is applied to the direction vertical to the circumference of the iron core to be treated by using the magnet; and the magnetic filed intensity at the central point of the hearth is 0-800Gs and can be continuously adjusted. The process and the equipment can be used for treating crystalline or amorphous magnetically soft alloy iron cores, the Curie temperatures of which are lower than 600 DEG C; the magnetic filed intensity in the center of the hearth is as high as 800Gs; and the invention has the advantages of low construction cost, high production efficiency as well as low cost and energy consumption.
Description
Technical field
The present invention relates to the material field, be specially a kind of preparation technology and equipment of permanent magnetic core, particularly utilize transverse magnetic field thermal treatment to prepare the technology of permanent magnetic core and electromagnet type transverse magnetic field heat treatment furnace.
Background technology
Soft magnetic materials all is widely used in modern electric power industry, power electronics industry and electronic industry.To the requirement of soft magnetic device, it is to need iron core under the effect of big magneticstrength H that a class is arranged, and has constant magnetic permeability μ, looks the use occasion difference, and its numerical value requires not wait from 10～200,000.
The present situation of permanent magnetoconductivity material is as follows:
(1) the permanent magnetoconductivity material that occurs the earliest is a magnetic powder core, and its magnetic permeability μ is generally 2～200, and material has straight iron powder, iron nickel powder, iron nickel molybdenum powder and iron aluminum silicon powder etc., closely during the last ten years, iron copper niobium silicon boron powder also occurred.
(2) utilize the demagnetization effects principle, offer an air gap in the heart, make magnetic permeability μ unshakable in one's determination reduce to 10～1000 and do not wait according to service requirements at the soft magnet of a closed magnetic circuit.
(3) producing permanent magnetic permeability iron core with the crystallization method, under crystallization temperature, is the trickle crystal grain of easy magnetization axis perpendicular to zone face with the iron-based non-crystalline alloy crystallization promptly, and its magnetic permeability μ is generally 500～4000.
(4) iron core is applied transverse magnetic field thermal treatment, for having horizontal preferably magnetic heat treatment effect, the magnetocrystalline anisotropy constant K of core material and magnetostriction coefficient λ s should go to zero, so magnetic permeability μ is higher, between 1000～200,000.Its treatment process is perpendicular to being added a magneticstrength H by the direction of heat treated closed magnetic circuit girth unshakable in one's determination, because iron core is opened a way with respect to the direction of the action of a magnetic field, has therefore produced a demagnetizing field H opposite with externally-applied magnetic field H at upper and lower ends unshakable in one's determination
N, then act on the true magnetic field H on the iron core
iFor
H
i＝H-H
N＝H-Nd×J
Wherein, Nd is a demagnetizing factor unshakable in one's determination, and J is a magneticpolarization unshakable in one's determination under the treatment temp, and the J value of nanocrystalline iron core under 500 ℃ is generally more than the 1000Gs, therefore requires externally-applied magnetic field H high more good more, do not make squareness ratio B unshakable in one's determination otherwise reach
r/ B
sThe effect that goes to zero.
Magnetic field H is generally produced by the current coil of energising, can lead to direct current or low frequency ac.
Along with the electronic technology development, constantly increase for the demand unshakable in one's determination of magnetic permeability μ between 1000～200,000, as employed current transformer iron core, split hair caccuracy current transformer iron core, wideband common mode inductance iron core, high-power IGBT invertor iron core and unidirectional pulse transformer core etc. in the antitheft electric watt-hour meter.Therefore, need improve raising,, enlarge turnout to reduce cost to the transverse magnetic field heat treatment technics.
Be used for the heat treated equipment of transverse magnetic field at present mainly by vacuum heat treatment or by the heat treatment furnace of protective atmosphere and can form to Magnetic Field Source two portions that closed circuit iron core applies transverse field strength H.Solenoid type transverse magnetic field heat treatment furnace is at the outside sheathed solenoid coil of heat treatment furnace, places pending iron core at the burner hearth center.By prior heat treatment process, make iron core have best magnetic property, near Curie temperature unshakable in one's determination, add enough magneticstrength H simultaneously, the magnetic domain in the iron core is arranged along the externally-applied magnetic field direction, and maintain this direction all the time along with temperature descends.
For satisfying batch production requirements, the burner hearth of this equipment needs enough spaces, as Φ 400mm * 600mm; And required magneticstrength should be more than 1000Gs; Like this, the minimum outer diameter size of heat treatment furnace will be at Φ 800mm * 1000mm, and then solenoidal volume is very big, and the general magnetic field kinetic potential F that produces is not less than 180KATs, so cost cost height.If will reduce cost, then necessary minification, furnace volume also can reduce like this, and each quantity of handling unshakable in one's determination of producing also greatly reduces, and production efficiency is not high.
In addition, will the solenoid coil that apply magnetic field being cooled off when thermal treatment, is to use cooled with liquid nitrogen generally speaking, also needs to cause the raising of equipment manufacturing cost and production cost with the liquid nitrogen retrieving arrangement.
The Curie temperature of Al-Ni-Co permanent magnet is many more than 780 ℃, and the Curie temperature of amorphous alloy is at 200 ℃～370 ℃, nanometer crystal alloy is about 570 ℃, therefore in experiment, should adopt permanent magnet as Magnetic Field Source, be added in pending two ends unshakable in one's determination, put into heat treatment furnace together and process; But this is not suitable for scale operation, especially to amorphous alloy, because under the permanent the action of a magnetic field of fixed, the operation that picks and places iron core is very dangerous.
Therefore, need make improvements,, cut down the consumption of energy, reduce cost to enhance productivity to prior art.
Summary of the invention
The present invention aims to provide a kind of method of utilizing transverse magnetic field thermal treatment to prepare permanent magnetic core.
The present invention also provides the electromagnet type transverse magnetic field heat treatment furnace of implementing aforesaid method.
A kind of transverse magnetic field heat treatment furnace comprises process furnace and electro-magnet, and the field direction that electro-magnet produced is parallel to the vertical direction with process furnace; The structure of process furnace comprises furnace shell and the formed burner hearth of furnace shell; The furnace shell inboard is provided with heating element.
The structure of electro-magnet comprises yoke and coil, and coil encircling is outside yoke.
Aforesaid device can be used for preparing permanent magnetic core, and step comprises: pending iron core is put into the burner hearth of transverse magnetic field heat treatment furnace, carry out thermal treatment earlier and make the excellent soft magnetic performance that obtains unshakable in one's determination; Utilizing heating element temperature in the burner hearth to be heated in the scope of pending Curie temperature unshakable in one's determination ± 10 ℃ again, apply magnetic field with electro-magnet to the direction perpendicular to the girth of pending iron core, is 0～800Gs in burner hearth central spot magneticstrength, adjustable continuously.
Thermal treatment comprises the steps: pending iron core vertically is placed in the burner hearth, under the vacuum or add dew-point temperature at-25～-50 ℃ nitrogen or argon gas, temperature in the stove is heated to below the Curie temperature 60 ℃～100 ℃, insulation 0.5～2hr; Speed with 30～60 ℃/hr is warming up to following 30 ℃～60 ℃ of Curie temperature, insulation 1～3hr; Be warming up in the scope of Curie temperature ± 10 ℃ insulation 0.5～2hr again with the speed of 30～60 ℃/hr; Cooling.
Iron core can be crystalline state or amorphous non-retentive alloy, and its Curie temperature is 100～600 ℃
Technology of the present invention and equipment can be used to handle crystalline state or the amorphous soft magnetic alloy iron core that Curie temperature is lower than 600 ℃, and the magneticstrength height of equipment center point reaches as high as 800Gs, and magneticstrength is adjustable continuously; Preparation-obtained permanent magnetic core magnetic permeability is 1000～200,000.Compare with solenoid type transverse magnetic field heat treatment furnace, cost reduces by more than 50, and reaches the same needed electric energy of magneticstrength and can be reduced to 1/5th of solenoid type transverse magnetic field heat treatment furnace, does not also need Magnetic Field Source is lowered the temperature; In addition, this equipment has bigger furnace volume, and the treatable quantity unshakable in one's determination of single production is increased, and can enhance productivity.Therefore, the present invention can save equipment and production cost greatly, cuts down the consumption of energy.
Description of drawings
Fig. 1 is the structural representation of electromagnet type transverse magnetic field heat treatment furnace among the embodiment 1
Fig. 2 is the longitudinal diagram of solenoid type transverse magnetic field heat treatment furnace among the comparative example
The 1-iron core, 2-process furnace, 201-furnace shell, 202-burner hearth, 203-heating element, 3-electro-magnet, 301-yoke, 302-coil, 303-magnetic pole, 501-furnace shell, 502-burner hearth, 503-heating element, 504-thermal insulation layer, 505-solenoid coil
Embodiment
As shown in Figure 1, the electromagnet type transverse magnetic field heat treatment equipment, its structure comprises process furnace 2 and electro-magnet 3, the field direction that two magnetic poles 303 of electro-magnet are produced is parallel with the vertical direction of process furnace.
The structure of process furnace comprises the formed burner hearth 202 in furnace wall 201 and furnace wall; The inboard, furnace wall is provided with heating element 203.The size of burner hearth is Φ 400mm * 600mm.
So-called electro-magnet comprises yoke 301 and coil 302, and coil encircling is outside yoke.The material of yoke is a pure iron.
The magneticstrength H calculating formula that electro-magnet produced is:
H＝N×I/L＝k×I
Wherein N is the number of turn of hot-wire coil, and I is a magnetzation current, and L is the electro-magnet gas length.Constant k value in the present embodiment is 38.30e/A.
Being added in magneticstrength H on the iron core is by the mmf that current coil produces the yoke of pure iron to be magnetized, and presses B=μ H, and magnetizer (being pure iron) is magnetized to the B value, if μ 5, then the magneticstrength of its generation is about 5 times of solenoid type.
The material unshakable in one's determination that uses is nano-crystal soft magnetic alloy, and as the nanocrystalline Shu Hejin band of 1K107, typical chemical molecular formula is Fe
73.5Cu
1Nb
3Si
13.5B
9Its Curie temperature is at 570 ℃.
Pending iron core vertically is placed in the burner hearth, carries out prior heat treatment process earlier, make iron core have best soft magnetic performance: promptly under vacuum, perhaps add dew-point temperature, temperature in the stove is heated to 470 ℃, insulation 1.5hr at-40 ℃ nitrogen or argon gas; Speed with 50 ℃/hr is warming up to 520 ℃, insulation 1.5hr; Speed with 50 ℃/hr is warming up to 560 ℃ again, insulation 1hr; Be cooled to 90 ℃.
Temperature in the burner hearth being readjusted in 560 ℃～580 ℃ the scope and be incubated 1hr, apply magnetic field with electro-magnet to the direction perpendicular to the girth of pending iron core, is 600Gs in burner hearth central spot magneticstrength.Applying neglecting greatly of magneticstrength magnetic permeability unshakable in one's determination reaches required numerical value and decides.Magneticstrength as required, and is from 0～800Oe, adjustable continuously.
Handle the resulting permanent magnetic core in back with aforesaid method, its magnetic permeability μ can reach 1000～200,000.
The comparative example
As shown in Figure 2, a kind of solenoid type transverse magnetic field heat treatment furnace, its structure comprises outer field furnace shell 501, and iron core 1 vertically is placed on burner hearth 502 centers, radially outwards sets gradually heating element 503, thermal insulation layer 504 and solenoid coil 505.
Carry out prior heat treatment process earlier, make iron core have best magnetic property; When temperature reaches near the unshakable in one's determination Curie temperature (± 10 ℃) in stove, apply magneticstrength H, magnetic domain unshakable in one's determination is arranged along the externally-applied magnetic field direction, and maintains this direction all the time along with temperature descends, and then Tie Xin magnetization characteristic can form flat magnetic hysteresis loop.
0 at center at solenoid coil axis A-A ' is located, and magneticstrength is calculated as follows:
Wherein N is the number of turn of institute's coiling on the solenoid coil, and I is the solenoidal electric current (ampere) of flowing through, R
1Be pore radius in the solenoid coil, R
2Be the solenoid coil exradius, L is a solenoid length, α=R
1/ R
2, β=L/R
1
At size of burner hearth is under the situation of Φ 400mm * 600mm, if will reach the magnetic field of 600Gs, this equipment minimum outer diameter size will be at Φ 800mm * 1000mm, and then solenoidal volume is very big, and the general magnetic field kinetic potential F that produces is not less than 180KATs.In addition, also need cooling apparatus that solenoid coil is lowered the temperature.
From embodiment 1 and comparative example, among the embodiment 1, the magneticstrength H that is added on the iron core magnetizes the pure iron yoke by the mmf that current coil produces, press B=μ H, iron core is magnetized to the B value, if μ 5, then the magneticstrength of its generation is about 5 times of solenoid type (comparative example), therefore, embodiment 1 and comparative example are if will obtain identical magneticstrength, embodiment 1 required strength of current and energy consumption is comparative example's 1/5th, and do not need cooling apparatus that electro-magnet is lowered the temperature.
Claims (7)
1. an electromagnet type transverse magnetic field heat treatment equipment is characterized in that, comprises process furnace (2) and electro-magnet (3), and the field direction that electro-magnet (3) is produced is parallel with the vertical direction of process furnace (2);
The structure of process furnace (2) comprises furnace shell (201) and the formed burner hearth of furnace shell (201) (202); Furnace shell (201) inboard is provided with heating element (203).
2. the described a kind of electromagnet type transverse magnetic field heat treatment equipment of claim 1 is characterized in that, the structure of described electro-magnet (3) comprises yoke (301) and coil (302), and coil (302) is looped around outside the yoke (301).
3. claim 1 or 2 described a kind of electromagnet type transverse magnetic field heat treatment equipments is characterized in that described electro-magnet (3) has air gap.
4. a method for preparing permanent magnetic core is characterized in that step comprises: pending iron core is placed in the burner hearth (202) of the described transverse magnetic field heat treatment equipment of claim 1～3, carry out thermal treatment earlier and make the soft magnetic performance that obtains unshakable in one's determination; Just the interior temperature of burner hearth (202) is adjusted in the scope of pending Curie temperature unshakable in one's determination ± 10 ℃ again, applies magnetic field with electro-magnet to the direction perpendicular to the girth of pending iron core, is 0～800Gs in burner hearth central spot magneticstrength.
5. the method for the permanent magnetic core of the described preparation of claim 4 is characterized in that, described iron core is crystalline state or amorphous non-retentive alloy, and its Curie temperature is 100～600 ℃.
6. the method for the permanent magnetic core of the described preparation of claim 4, it is characterized in that, described thermal treatment comprises the steps: vertically to be placed on pending iron core in the burner hearth, under the vacuum or add dew-point temperature at-25～-50 ℃ nitrogen or argon gas, temperature in the stove is heated to below the Curie temperature 60 ℃～100 ℃, insulation 0.5～2hr; Speed with 30～60 ℃/hr is warming up to following 30 ℃～60 ℃ of Curie temperature, insulation 1～3hr; Be warming up in the scope of Curie temperature ± 10 ℃ insulation 0.5～2hr again with the speed of 50 ℃/hr; Cooling.
7. the method for the permanent magnetic core of the described preparation of claim 4 is characterized in that, described core material is a nano-crystal soft magnetic alloy.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105719826A (en) * | 2016-01-22 | 2016-06-29 | 东南大学 | Magnetic-field heat treatment method of nanocrystal magnetic core |
| CN106158344A (en) * | 2016-08-30 | 2016-11-23 | 贵州鑫湄纳米科技有限公司 | A kind of ZCT magnetic core Annealing Crystallization technique |
| CN107475496A (en) * | 2017-08-16 | 2017-12-15 | 贵州鑫湄纳米科技有限公司 | The heat treatment method of iron-based amorphous core material |
| CN108774674A (en) * | 2018-06-29 | 2018-11-09 | 华北电力大学 | A kind of magnetic heat treatment furnace |
| CN113029235A (en) * | 2021-02-25 | 2021-06-25 | 哈尔滨工业大学 | Small-stroke nanoscale motion platform and heat-related hysteresis data measuring method |
| CN113096914A (en) * | 2021-03-18 | 2021-07-09 | 钢铁研究总院 | Device and method for applying magnetic field to high-temperature heat source |
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| CN2202751Y (en) * | 1994-02-05 | 1995-07-05 | 冶金工业部钢铁研究总院 | Magnetic thermal treatment apparatus for soft-magnetic elements and devices |
| CN1760379A (en) * | 2005-11-03 | 2006-04-19 | 徐宝田 | Heat treatment method and equipment through rotating magnetic field generated from magnetic parts of an apparatus |
| CN101555544A (en) * | 2009-05-19 | 2009-10-14 | 佛山市中研非晶科技股份有限公司 | Heat treatment facility for soft magnetic winding core in transverse magnetic field and method thereof |
| CN201704357U (en) * | 2010-05-21 | 2011-01-12 | 上海世路特种金属材料有限公司 | Electromagnet type transverse magnetic field thermal processing equipment |
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Patent Citations (4)
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| CN2202751Y (en) * | 1994-02-05 | 1995-07-05 | 冶金工业部钢铁研究总院 | Magnetic thermal treatment apparatus for soft-magnetic elements and devices |
| CN1760379A (en) * | 2005-11-03 | 2006-04-19 | 徐宝田 | Heat treatment method and equipment through rotating magnetic field generated from magnetic parts of an apparatus |
| CN101555544A (en) * | 2009-05-19 | 2009-10-14 | 佛山市中研非晶科技股份有限公司 | Heat treatment facility for soft magnetic winding core in transverse magnetic field and method thereof |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105719826A (en) * | 2016-01-22 | 2016-06-29 | 东南大学 | Magnetic-field heat treatment method of nanocrystal magnetic core |
| CN106158344A (en) * | 2016-08-30 | 2016-11-23 | 贵州鑫湄纳米科技有限公司 | A kind of ZCT magnetic core Annealing Crystallization technique |
| CN107475496A (en) * | 2017-08-16 | 2017-12-15 | 贵州鑫湄纳米科技有限公司 | The heat treatment method of iron-based amorphous core material |
| CN108774674A (en) * | 2018-06-29 | 2018-11-09 | 华北电力大学 | A kind of magnetic heat treatment furnace |
| CN113029235A (en) * | 2021-02-25 | 2021-06-25 | 哈尔滨工业大学 | Small-stroke nanoscale motion platform and heat-related hysteresis data measuring method |
| CN113029235B (en) * | 2021-02-25 | 2021-09-10 | 哈尔滨工业大学 | Small-stroke nanoscale motion platform and heat-related hysteresis data measuring method |
| CN113096914A (en) * | 2021-03-18 | 2021-07-09 | 钢铁研究总院 | Device and method for applying magnetic field to high-temperature heat source |
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