CN111009405A - Magnetic powder preparation process - Google Patents
Magnetic powder preparation process Download PDFInfo
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- CN111009405A CN111009405A CN201911094035.5A CN201911094035A CN111009405A CN 111009405 A CN111009405 A CN 111009405A CN 201911094035 A CN201911094035 A CN 201911094035A CN 111009405 A CN111009405 A CN 111009405A
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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
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Abstract
The invention discloses a magnetic powder preparation process, which comprises the following steps: putting the mixture into a metal powder grinding device to grind a metal powder preparation raw material; putting the powder into a metal powder screening device, and screening impurities and oversize powder in various powdery metal powder preparation raw materials; putting the mixture into a metal powder stirring and heating device to uniformly distribute the low-hardness plastic metal powder in the sendust powder; adding a passivating agent into the prepared mixed powder for passivation treatment; sealing the metal powder stirring and heating device, vacuumizing the stirring barrel, and then filling argon; heating the sendust magnetic powder; the metal powder stirring and heating device stops heating. The method has small limitation on equipment and high production efficiency, and can improve the production quality of magnetic powder by grinding and screening the powder; the hardness and brittleness of the powder particles can be reduced through heating treatment, and the material of the inner wall of the barrel is the same as that of the processed material, so that pollution is prevented.
Description
Technical Field
The invention relates to the technical field of magnetic powder processing, in particular to a magnetic powder preparation process.
Background
Modern switching power supplies are widely used in various active electrical appliances, such as computers, LED televisions, communication hardware, household appliances, etc., due to their high energy conversion efficiency and high stability. It has become, so to speak, an indispensable key device for modern life and production.
The efficiency is high, on one hand, the wide application of the metal oxide semiconductor field effect transistor is realized, so that the electric energy loss caused by the electric inertia when the traditional switching device is changed in an on state and an off state is reduced; another important reason is that the capacitance and inductance are effectively used together so that energy can be efficiently transferred in the circuit.
Capacitors and inductors are reactive components, have a unique energy storage function, do not consume energy like resistive components, and are therefore essential components of modern switching power supplies. The inductor plays a key role in a related power supply as a power factor correction inductor, an output filter inductor, a resonance inductor, an EMI inductor and the like; however, in the actual use process, the magnetic material inevitably has energy losses such as hysteresis loss, eddy current loss at high frequency, and copper loss, and the inductance causes more or less energy transfer loss. It is therefore critical and essential to investigate how to reduce this inevitable loss for switching power supplies; relevant practical data demonstrate that: the service life of the switching power supply is reduced by 50% when the service temperature of the switching power supply is increased by 10 ℃. In addition, the inductor has a dc bias problem in an operating state, and therefore, it is very critical and necessary to research how to improve the dc bias resistance of the switch power supply.
The inductors are mainly divided into differential mode inductors and common mode inductors, and the common differential mode inductors comprise permalloy magnetic powder cores, iron-silicon-aluminum magnetic powder cores and the like. The iron powder core has higher direct current bias capability but high loss, and is only suitable for working at lower frequency; the permalloy can obtain two magnetic powder cores by adjusting the components, one is MPP, the other is HighFlux, and the two magnetic powder cores respectively have the characteristics of high frequency, low loss and high saturation magnetic induction intensity, and are only suitable for equipment with higher requirements due to expensive price.
The Fe-Si-Al alloy consists of Al-Si-Fe, has magnetic core loss far lower than that of an iron powder core and high magnetic flux, has low magnetostriction (low noise), is an energy storage material with low cost, does not have thermal aging, can be used for replacing the iron powder core, and has very stable performance at high temperature. The soft magnetic iron-silicon-aluminum powder is prepared mainly by an atomization method and a mechanical crushing method, the powder prepared by the atomization method has good performance, the powder is spherical in shape, but the production cost is high, and the yield is limited by conditions; the powder prepared by the mechanical crushing method has low production cost, but the produced powder particles have obvious sharp corners, and after the insulation coating is carried out by the later surface treatment, the sharp corners are easy to puncture the insulation coating layer when the powder core is pressed; the original appearance treatment uses an air flow mill and a Hammette shaping, and has large power consumption, complex equipment and low yield.
Disclosure of Invention
The invention aims to provide a magnetic powder preparation process to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: a process for preparing magnetic powder comprises the following steps:
step one, respectively putting a plurality of metal powder preparation raw materials into a metal powder grinding device, and respectively grinding the metal powder preparation raw materials for 20 minutes to 3 hours;
step two, respectively putting the various powdered metal powder preparation raw materials into a metal powder screening device, respectively screening the various powdered metal powder preparation raw materials, screening impurities and oversize powder in the powdered metal powder preparation raw materials, and collecting the qualified powdered metal powder preparation raw materials;
step three, putting the ground and screened low-hardness plastic metal powder and the iron-silicon-aluminum metal powder into a metal powder stirring and heating device, and uniformly distributing the low-hardness plastic metal powder in the iron-silicon-aluminum powder, wherein the weight ratio of the low-hardness plastic metal powder to the iron-silicon-aluminum metal powder is 1: 100-6000;
step four, adding a passivating agent into the prepared mixed powder for passivation treatment, wherein the dosage of the passivating agent is 0.2-0.35% of the weight of the mixed powder;
step five, sealing the metal powder stirring and heating device, vacuumizing the stirring barrel to-100 kpa to-200 kpa, then filling argon, and adjusting the pressure to 1.2kpa to 3 kpa;
sixthly, heating the sendust magnetic powder to 260-320 ℃, operating at the rotating speed of 15-25rpm for 1-5 hours, then adjusting the rotating speed to 40-80 rpm, keeping the temperature at 260 ℃, and stirring for 2.5-5 hours;
and step seven, stopping heating the metal powder stirring and heating device, adjusting the rotating speed to 15-25rpm, and operating for 1-5 hours.
Preferably, the material of the inner wall of the metal powder stirring and heating device is the same as that of the sendust.
Preferably, the low-hardness plastic metal powder is one or a mixture of two of iron powder and permalloy powder, the powder is flat, the planar width is 20-100um, the thickness is 1-5um, and the surface oxygen content is less than 1000 ppm.
Preferably, the passivating agent is a phosphoric acid diluent, and the preparation method comprises the following steps: firstly, weighing the weight of phosphoric acid on an electronic balance, and then adding a diluent which is 15 times of the weight of the phosphoric acid into the phosphoric acid for uniform mixing, wherein the diluent is alcohol, water or a mixed solution of the alcohol and the water.
Preferably, the lateral wall of metal powder stirring heating device embeds there is condenser tube, condenser tube is connected with coolant tank, can force the cooling to the powder after the heating is accomplished through condenser tube.
Preferably, a battery coil is built in the bottom of the metal powder stirring and heating device.
Preferably, metal powder grinder, metal powder screening plant and metal powder stirring heating device respectively with PLC switch board electric connection, can set for and control metal powder grinder, metal powder screening plant and metal powder stirring heating device through production line PLC switch board.
Compared with the prior art, the invention has the beneficial effects that: the method has the advantages that the limitation on equipment is small, the production efficiency is high, and the production quality of the magnetic powder can be improved by grinding and screening the powder; the hardness and brittleness of the powder particles can be reduced through heating treatment, and the shaping efficiency is improved; the material of the inner wall of the barrel is the same as the processed material, so that pollution is prevented.
Drawings
FIG. 1 is a process flow diagram of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Referring to fig. 1, the present invention provides a technical solution: a process for preparing magnetic powder comprises the following steps:
step one, respectively putting a plurality of metal powder preparation raw materials into a metal powder grinding device, and respectively grinding the metal powder preparation raw materials for 30 minutes;
step two, respectively putting the various powdered metal powder preparation raw materials into a metal powder screening device, respectively screening the various powdered metal powder preparation raw materials, screening impurities and oversize powder in the powdered metal powder preparation raw materials, and collecting the qualified powdered metal powder preparation raw materials;
step three, putting the ground and screened low-hardness plastic metal powder and the iron-silicon-aluminum metal powder into a metal powder stirring and heating device, and uniformly distributing the low-hardness plastic metal powder in the iron-silicon-aluminum powder, wherein the weight ratio of the low-hardness plastic metal powder to the iron-silicon-aluminum metal powder is 1: 100-6000, taking 100g of low-hardness plastic metal powder and 20kg of-200-mesh ferrosilicon aluminum metal powder;
step four, adding a passivating agent into the prepared mixed powder for passivation treatment, wherein the using amount of the passivating agent is 0.25 percent of the weight of the mixed powder;
step five, sealing the metal powder stirring and heating device, vacuumizing the stirring barrel to-120 kpa, then filling argon, and adjusting the pressure to 1.6 kpa;
sixthly, heating the sendust to 300 ℃, operating at the rotating speed of 18rpm for 2.5 hours, then adjusting the rotating speed to 50rpm, keeping the temperature at 260 ℃, and stirring for 3 hours;
and step seven, stopping heating the metal powder stirring and heating device, adjusting the rotating speed to 18rpm, and operating for 3 hours.
Specifically, the material of the inner wall of the metal powder stirring and heating device is the same as that of the sendust magnetic powder.
Specifically, the low-hardness plastic metal powder is one or a mixture of two of iron powder or permalloy powder, the powder is flat, the planar width is 20-100um, the thickness is 1-5um, and the surface oxygen content is less than 1000 ppm.
Specifically, the passivating agent is phosphoric acid diluent, and the preparation method comprises the following steps: firstly, weighing the weight of phosphoric acid on an electronic balance, and then adding a diluent which is 15 times of the weight of the phosphoric acid into the phosphoric acid for uniform mixing, wherein the diluent is alcohol, water or a mixed solution of the alcohol and the water.
Specifically, the lateral wall of metal powder stirring heating device embeds there is condenser tube, condenser tube is connected with coolant tank, can force the cooling to the powder after the heating is accomplished through condenser tube.
Specifically, a battery coil is built in the bottom of the metal powder stirring and heating device.
Particularly, metal powder grinder, metal powder screening plant and metal powder stirring heating device respectively with PLC switch board electric connection, can set for and control metal powder grinder, metal powder screening plant and metal powder stirring heating device through production line PLC switch board.
Example 2
Referring to fig. 1, the present invention provides a technical solution: a process for preparing magnetic powder comprises the following steps:
step one, respectively putting a plurality of metal powder preparation raw materials into a metal powder grinding device, and respectively grinding the metal powder preparation raw materials for 2.5 hours;
step two, respectively putting the various powdered metal powder preparation raw materials into a metal powder screening device, respectively screening the various powdered metal powder preparation raw materials, screening impurities and oversize powder in the powdered metal powder preparation raw materials, and collecting the qualified powdered metal powder preparation raw materials;
step three, putting the ground and screened low-hardness plastic metal powder and the iron-silicon-aluminum metal powder into a metal powder stirring and heating device, and uniformly distributing the low-hardness plastic metal powder in the iron-silicon-aluminum powder, wherein the weight ratio of the low-hardness plastic metal powder to the iron-silicon-aluminum metal powder is 1: 100-6000, taking 5Kg of low-hardness plastic metal powder and 1000Kg of-200-mesh Fe-Si-Al metal powder;
step four, adding a passivating agent into the prepared mixed powder for passivation treatment, wherein the using amount of the passivating agent is 0.32 percent of the weight of the mixed powder;
step five, sealing the metal powder stirring and heating device, vacuumizing the stirring barrel to-180 kpa, then filling argon, and adjusting the pressure to 2.8 kpa;
sixthly, heating the sendust to 300 ℃, operating at the rotation speed of 22rpm for 4 hours, then adjusting the rotation speed to 70rpm, keeping the temperature at 260 ℃, and stirring for 4.5 hours;
and step seven, stopping heating the metal powder stirring and heating device, adjusting the rotating speed to 21rpm, and operating for 3.5 hours.
Specifically, the material of the inner wall of the metal powder stirring and heating device is the same as that of the sendust magnetic powder.
Specifically, the low-hardness plastic metal powder is one or a mixture of two of iron powder or permalloy powder, the powder is flat, the planar width is 20-100um, the thickness is 1-5um, and the surface oxygen content is less than 1000 ppm.
Specifically, the passivating agent is phosphoric acid diluent, and the preparation method comprises the following steps: firstly, weighing the weight of phosphoric acid on an electronic balance, and then adding a diluent which is 15 times of the weight of the phosphoric acid into the phosphoric acid for uniform mixing, wherein the diluent is alcohol, water or a mixed solution of the alcohol and the water.
Specifically, the lateral wall of metal powder stirring heating device embeds there is condenser tube, condenser tube is connected with coolant tank, can force the cooling to the powder after the heating is accomplished through condenser tube.
Specifically, a battery coil is built in the bottom of the metal powder stirring and heating device.
Particularly, metal powder grinder, metal powder screening plant and metal powder stirring heating device respectively with PLC switch board electric connection, can set for and control metal powder grinder, metal powder screening plant and metal powder stirring heating device through production line PLC switch board.
In the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The standard parts used in the invention can be purchased from the market, the special-shaped parts can be customized according to the description of the specification and the accompanying drawings, the specific connection mode of each part adopts conventional means such as bolts, rivets, welding and the like mature in the prior art, the machines, the parts and equipment adopt conventional models in the prior art, and the circuit connection adopts the conventional connection mode in the prior art, so that the detailed description is omitted.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (7)
1. A process for preparing magnetic powder is characterized by comprising the following steps:
step one, respectively putting a plurality of metal powder preparation raw materials into a metal powder grinding device, and respectively grinding the metal powder preparation raw materials for 20 minutes to 3 hours;
step two, respectively putting the various powdered metal powder preparation raw materials into a metal powder screening device, respectively screening the various powdered metal powder preparation raw materials, screening impurities and oversize powder in the powdered metal powder preparation raw materials, and collecting the qualified powdered metal powder preparation raw materials;
step three, putting the ground and screened low-hardness plastic metal powder and the iron-silicon-aluminum metal powder into a metal powder stirring and heating device, and uniformly distributing the low-hardness plastic metal powder in the iron-silicon-aluminum powder, wherein the weight ratio of the low-hardness plastic metal powder to the iron-silicon-aluminum metal powder is 1: 100-6000;
step four, adding a passivating agent into the prepared mixed powder for passivation treatment, wherein the dosage of the passivating agent is 0.2-0.35% of the weight of the mixed powder;
step five, sealing the metal powder stirring and heating device, vacuumizing the stirring barrel to-100 kpa to-200 kpa, then filling argon, and adjusting the pressure to 1.2kpa to 3 kpa;
sixthly, heating the sendust magnetic powder to 260-320 ℃, operating at the rotating speed of 15-25rpm for 1-5 hours, then adjusting the rotating speed to 40-80 rpm, keeping the temperature at 260 ℃, and stirring for 2.5-5 hours;
and step seven, stopping heating the metal powder stirring and heating device, adjusting the rotating speed to 15-25rpm, and operating for 1-5 hours.
2. A process for preparing magnetic powder according to claim 1, wherein: the material of the inner wall of the metal powder stirring and heating device is the same as that of the sendust magnetic powder.
3. A process for preparing magnetic powder according to claim 1, wherein: the low-hardness plastic metal powder is one or a mixture of two of iron powder or permalloy powder, the powder is flat, the plane width is 20-100um, the thickness is 1-5um, and the surface oxygen content is less than 1000 ppm.
4. A process for preparing magnetic powder according to claim 1, wherein: the passivating agent is phosphoric acid diluent, and the preparation method comprises the following steps: firstly, weighing the weight of phosphoric acid on an electronic balance, and then adding a diluent which is 15 times of the weight of the phosphoric acid into the phosphoric acid for uniform mixing, wherein the diluent is alcohol, water or a mixed solution of the alcohol and the water.
5. A process for preparing magnetic powder according to claim 1, wherein: and a cooling water pipe is arranged in the side wall of the metal powder stirring and heating device and is connected with a cooling water tank.
6. A process for preparing magnetic powder according to claim 1, wherein: and a battery coil is arranged in the bottom of the metal powder stirring and heating device.
7. A process for preparing magnetic powder according to claim 1, wherein: and the metal powder grinding device, the metal powder screening device and the metal powder stirring and heating device are respectively electrically connected with the PLC control cabinet.
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| CN103495725A (en) * | 2013-09-27 | 2014-01-08 | 青岛联瑞精密机械有限公司 | Shape treating method for iron silicon aluminum soft magnetic powdery particles |
| JP2016033971A (en) * | 2014-07-31 | 2016-03-10 | 住友金属鉱山株式会社 | Method for manufacturing rare earth-transition metal-nitrogen based magnet powder of high weather resistance, and rare earth-transition metal-nitrogen based magnet powder of high weather resistance |
| CN105903951A (en) * | 2016-05-23 | 2016-08-31 | 苏州思创源博电子科技有限公司 | Preparation method of magnetically soft alloy powder |
| CN107675074A (en) * | 2017-08-23 | 2018-02-09 | 南京新康达磁业股份有限公司 | A kind of soft magnetic metal sendust powder and preparation method thereof |
| CN108417332A (en) * | 2018-03-13 | 2018-08-17 | 海宁市天丰磁业有限公司 | A kind of ferroalloy magnetic material preparation method |
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2019
- 2019-11-11 CN CN201911094035.5A patent/CN111009405A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102945720A (en) * | 2012-10-15 | 2013-02-27 | 广州市德珑电子器件有限公司 | Preparation method of sendust core with high direct current bias characteristic |
| CN103495725A (en) * | 2013-09-27 | 2014-01-08 | 青岛联瑞精密机械有限公司 | Shape treating method for iron silicon aluminum soft magnetic powdery particles |
| JP2016033971A (en) * | 2014-07-31 | 2016-03-10 | 住友金属鉱山株式会社 | Method for manufacturing rare earth-transition metal-nitrogen based magnet powder of high weather resistance, and rare earth-transition metal-nitrogen based magnet powder of high weather resistance |
| CN105903951A (en) * | 2016-05-23 | 2016-08-31 | 苏州思创源博电子科技有限公司 | Preparation method of magnetically soft alloy powder |
| CN107675074A (en) * | 2017-08-23 | 2018-02-09 | 南京新康达磁业股份有限公司 | A kind of soft magnetic metal sendust powder and preparation method thereof |
| CN108417332A (en) * | 2018-03-13 | 2018-08-17 | 海宁市天丰磁业有限公司 | A kind of ferroalloy magnetic material preparation method |
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