CN113674984B - Preparation method of FeSiAlZrScSr magnetic powder core - Google Patents
Preparation method of FeSiAlZrScSr magnetic powder core Download PDFInfo
- Publication number
- CN113674984B CN113674984B CN202110988588.6A CN202110988588A CN113674984B CN 113674984 B CN113674984 B CN 113674984B CN 202110988588 A CN202110988588 A CN 202110988588A CN 113674984 B CN113674984 B CN 113674984B
- Authority
- CN
- China
- Prior art keywords
- powder
- magnetic
- magnetic powder
- fesial
- powder core
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- 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
-
- 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
- H01F1/147—Alloys characterised by their composition
- H01F1/14766—Fe-Si based alloys
- H01F1/14791—Fe-Si-Al based alloys, e.g. Sendust
-
- 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
-
- 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
- H01F27/34—Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
-
- 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 discloses a preparation method of a FeSiAlZrScSr magnetic powder core, wherein the FeSiAlZrScSr magnetic powder core contains the following chemical element components in percentage by mass: 9.0 to 9.6, al:5.2 to 5.6, zr: 1.2-2.0, sc:0.8 to 1.3, sr:0.2 to 0.7, and the balance of Fe. According to the invention, rare earth elements of scandium, zirconium and strontium are added into the FeSiAl powder, so that the hard brittleness of the FeSiAl magnetic powder can be reduced, and the magnetic property stability of the FeSiAl magnetic powder core is improved; secondly, by adopting a phosphate-yttrium oxide composite coating process, the coating layer enables the magnetic powder core to have strong corrosion resistance and high temperature resistance, effectively avoids the reduction of saturation magnetization and magnetic conductivity, and prepares the high-performance FeSiAl magnetic powder core under the condition of ensuring high magnetic conductivity.
Description
Technical Field
The invention belongs to the field of soft magnetic materials and rare earth elements, and particularly relates to a preparation method of a FeSiAlZrScSr magnetic powder core.
Background
With the development of the electronic information industry, the size of new power electronic devices and devices is required to be reduced, which also promotes the development of electronic components toward miniaturization, high frequency, low power consumption and high power. In the development of soft magnetic materials, the FeSiAl magnetic powder core has the advantages of high resistivity, low coercive force, high magnetic conductivity, good wear resistance and the like, so that the FeSiAl magnetic powder core is widely applied to electronic components such as transformers, inductors, choke coils and the like.
Compared with insulation coating, compression molding and heat treatment, the preparation of the magnetic powder in the first step is extremely important, and the performance of the magnetic powder is closely related to alloy components, crystal structures, grain sizes, particle morphologies and the like. The magnetic performance of the magnetic powder can be optimized by changing the alloy components of the magnetic powder. The aluminum element is added into the iron-silicon alloy, so that the composition and the crystal structure of the iron-silicon alloy phase are changed, and the soft magnetic alloy with excellent magnetic performance is obtained. However, the conventional FeSiAl magnetic powder core has high hardness and brittleness, cracks are easy to occur in the process of press forming, and the magnetic property stability of the FeSiAl magnetic powder core is deteriorated along with the deterioration of the external environment. For example, with the change of external severe environmental factors, a passive film on the surface of the coating layer can be easily damaged to cause the formation of pitting corrosion, so that Si and Fe in the magnetic powder can be more easily segregated to form a eutectic structure at a grain boundary to cause intergranular corrosion, the coating layer is cracked, the contact between powder particles can not be effectively blocked, the resistivity is reduced, the eddy current loss of the FeSiAl magnetic powder core is increased, and the superposition performance, the quality factor and the corrosion resistance of the magnetic powder core are reduced. Therefore, the FeSiAl magnetic powder prepared by the prior art has the defects of magnetic property stability, corrosion resistance and high temperature resistance of a coating layer, soft magnetic property of a magnetic powder core, loss and the like. In order to obtain the sendust soft magnetic powder core with comprehensive excellent magnetic performance, the research and development of a novel sendust magnetic powder core preparation process is urgently needed.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a preparation method of a FeSiAlZrScSr magnetic powder core.
On one hand, rare earth elements of scandium, zirconium and strontium are added into the FeSiAl powder, so that the hard brittleness of the FeSiAl magnetic powder can be reduced, and the magnetic property stability of the FeSiAl magnetic powder core is improved; on the other hand, by adopting a phosphate-yttrium oxide composite coating process, the coating layer enables the magnetic powder core to have strong corrosion resistance and high temperature resistance, improves the coating effect of the magnetic powder to a certain extent, effectively avoids the reduction of saturation magnetization and magnetic conductivity, and prepares the high-performance FeSiAl magnetic powder core under the condition of ensuring high magnetic conductivity.
The preparation method of the FeSiAlZrScSr magnetic powder core comprises the following steps:
s1, pulverizing: preparing FeSiAl, sc, zr and Sr powders by adopting a gas atomization mode, mixing the prepared FeSiAl powders with Sc, zr and Sr powders together, and annealing at the high temperature of 700-850 ℃ for 1.5-3 h under protective gas;
s2, phosphate coating: diluting phosphoric acid with anhydrous ethanol, adding phosphoric acid diluent into the mixed powder obtained in S1, adding yttrium oxide powder under stirring, and performing surface treatment, wherein the addition amount of phosphoric acid is 0.3wt% (this concentration isDegree refers to H in the system after phosphoric acid is added 3 PO 4 The concentration of (3) is the same as below), the addition amount of yttrium oxide is 0.2wt%, and the mixture is heated and stirred in a constant-temperature water bath at 50-70 ℃ until the mixed powder is dried;
s3, yttrium oxide coating: mixing 200 mesh of Y 2 O 3 The powder and the magnetic powder coated by the S2 phosphate are uniformly mixed according to the proportion, and the addition amount of the yttrium oxide is 3.8 to 6.8 weight percent. Adding a binder, wherein the addition amount of the binder is 0.2-0.6 wt%, and uniformly stirring; heating the uniformly stirred powder at the temperature of between 70 and 160 ℃, and continuously stirring the powder until the powder is dried;
s4, adding a lubricant: adding a lubricant accounting for 0.6 to 1.0 percent of the weight of the powder, and uniformly mixing;
s5, press forming: pressing and molding the powder under a press machine to form a magnetic powder core;
s6, graded annealing: under protective gas, firstly putting the magnetic powder core into a furnace with the temperature of 930 +/-10 ℃ for annealing, setting the heat preservation time to be 1.5-3 h and the heating rate to be 9 ℃/min; then the temperature is reduced to 450-500 ℃, and the heat preservation time is set to 1-2 h.
The particle size distribution of the mixed powder obtained in S1 is as follows: minus 150 to plus 200 meshes, accounting for 10 plus or minus 5 percent; minus 200 to +400 meshes, accounting for 70% +/-5%; minus 300 to plus 300 meshes, accounting for 20% +/-5%.
The FeSiAlZrScSr powder obtained by S1 comprises the following components in percentage by mass: si9.0-9.6%, al5.2-5.6%, zr1.2-2.0%, sc0.8-1.3%, sr0.2-0.7%, and the balance Fe.
In the preparation process of the invention, the protective gas is argon.
In step S3, the binder is a sodium silicate solution. The amount of the binder added is defined as 0.2 to 0.6wt% as above, and this ratio refers to the ratio of sodium silicate added.
In step S3, Y 2 O 3 The ratio of powder to FeSiAl powder is 1: (22-33).
In step S4, the lubricant is zinc stearate.
The design basis of the method is as follows:
fe: iron is one of the constituent elements of the magnetic material. The alloy steel is hard and malleable and has strong ferromagnetism, and the iron and a small amount of carbon are made into the alloy steel, so the alloy steel is not easy to demagnetize after being magnetized, is an excellent hard magnetic material, is an important industrial material and is also used as a main raw material of artificial magnetism.
Si: it has the functions of solid solution strengthening, raising heat resistance and corrosion resistance, and has great chemical affinity between Si and oxygen, so that the Si added into the magnet has strong deoxidizing agent for precipitation and diffusion deoxidation, and can improve the form of inclusion, reduce the content of gas element in the magnet, prevent iron from being oxidized and reduce the magnetism of magnetic powder core. However, si is liable to embrittle the alloy, and the amount is not so large.
Al: a small amount of Al element is added to dissolve Al in alpha-Fe, so that two different types of ordered phase structures Fe3Al and FeAl can be formed, the magnetic powder core has very high resistivity and low eddy current loss, the magnetocrystalline anisotropy constant tends to zero, the magnetostriction coefficient is high, the saturation magnetic induction intensity is high, and the soft magnetic performance is improved.
Zr: zirconium is a rare metal with surprising corrosion resistance, extremely high melting point, ultra-high hardness and strength, and the addition of a small amount of zirconium can deoxidize, purify, refine grains, and improve stamping properties.
And (C) Sc: scandium can reduce harmful iron-containing phase structure, and an Al3Sc new phase can be generated by adding a few thousandths of scandium into the iron-silicon-aluminum alloy, so that the iron-silicon-aluminum alloy is modified, and the structure and the performance of the alloy are obviously changed. And the high-temperature strength, the structural stability and the corrosion resistance are all obviously improved, and can avoid the embrittlement phenomenon which is easy to generate when the device works for a long time at high temperature.
Sr: sr is added into the FeSiAl alloy, the size of primary crystal silicon particles can be reduced, the beta-AlFeSi phase in the alloy is changed into Cheng Han-shaped alpha-AlFeSi phase, the homogenization time of the alloy is reduced, and the plastic processability of the alloy is improved.
The invention adds rare earth elements of Zr, sc and Sr, and the Al in the Zr, sc and Sr and FeSiAl magnetic powder to form AlSr5 and Al 3 Zr and Al 3 The new Sc phase has the function of modifying FeSiAl magnetic powder, and the grain size of the magnetic powder is refined to ensure that the magnetic powder is modifiedThe grain boundary area of the steel is increased, when plastic deformation occurs, the deformation is more uniform, and the stress concentration is small; sr is a surface active element, and can change the behavior of an intermetallic compound phase in crystallography, so that the beta-AlFeSi in the FeSiAl alloy is transformed into Cheng Han-shaped alpha-AlFeSi phase, the homogenization time of the alloy is reduced by 60-70%, the tensile strength of the FeSiAl alloy is improved from 233MPa to 336MPa, the yield strength is improved from 204MPa to 310MPa, and the elongation is improved from 9% to 22%. Therefore, the hardness and brittleness of the FeSiAl alloy are reduced, magnetic powder particles are prevented from cracking in the process of press forming, and the mechanical property and the cold pressing formability of the FeSiAl magnetic powder core are improved. In addition, due to the addition of Zr and Sc, eutectic compounds can be formed with Fe, the harmful ferrous phase structure is reduced, magnetic powder particles are arranged along the easy magnetization axis in an oriented mode, the arrangement trend of the magnetic moment directions of internal magnetic domains of the magnet is consistent, and the magnetic permeability of the soft magnetic material is arranged along the orientation of the magnetic moment direction of the magnetic domains in the external magnetic field direction, so that the magnetic permeability of the FeSiAl magnetic powder core can be kept stable regardless of the change of other external factors such as external temperature. Due to the addition of Zr, sc and Sr, the rare earth elements have the functions of purifying and modifying FeSiAl magnetic powder particles, so that the size and distribution of the magnetic powder particles are more uniform. Thus, after pressing the FeSiAl magnetic powder, the distributed air gaps between the magnetic powder particles are reduced, an effective two-dimensional material is presented, in which the eddy current losses are limited to the thickness between the magnetic powder particles, rather than within the particles, so that the grain boundary resistivity between the particles is increased, and the power loss of the FeSiAl magnetic powder core is reduced, as can be seen from P = U2/R.
According to the phosphate-yttrium oxide composite coating process, due to the fact that yttrium oxide has surface hydroxyl groups, the surface of yttrium oxide is immediately combined with water after the yttrium oxide is contacted with water molecules in a phosphate aqueous solution, and charged ion transfer occurs at a phase interface, so that the surface of yttrium oxide is hydroxylated, and the yttrium oxide can react with ligands in the solution. Under acidic conditions, the surface hydroxyl groups of yttrium oxide are protonated with H 2 PO 4 - And
generating single-tooth mononuclear and double-tooth pairsThe complex on the surface of the core improves the regularity of the molecular chain of the original phosphate coating layer, and causes the thermal stability of the phosphate film layer to be increased. And the thermal stability of the yttrium oxide is good, and the yttrium oxide has a large specific surface area and a porous structure when annealed at high temperature, so that the yttrium oxide can be better adsorbed on the surface of the phosphate coating layer, the coating insulating layer can not be decomposed at the annealing temperature lower than 1200 ℃, and the thermal stability of the phosphate-yttrium oxide composite coating layer is greatly improved. And the phosphate-yttria composite coating has higher resistivity than that of a phosphate/yttria single coating, and is formed by P = U 2 the/R shows that the power loss of the magnetic powder core is lower than that of the phosphate/yttrium oxide single coating layer.
The invention adopts a graded annealing process, firstly, the temperature is raised to 930 +/-10 ℃, the heat preservation time is set to 1.5-3 h, on one hand, the internal stress is completely released, and on the other hand, a part of Zr, sc and Sr enters a phosphate-yttrium oxide composite coating insulating layer through diffusion; then the temperature is reduced to 450-500 ℃ for annealing, the heat preservation time is set to 1.5-3 h, so that a small amount of Zr, sc and Sr is diffused to the interface of the phosphate-yttria coating layer to stop, and the enrichment of second phases such as FeAl3, siSc and the like on the interface is promoted and the second phases are distributed discontinuously. On one hand, the addition of the rare earth Sc, zr and Sr promotes the enrichment of a second phase on a grain boundary and the discontinuous distribution to form discontinuous corrosion channels, so that the initiation of micro-galvanic corrosion is reduced; on the other hand, the method is beneficial to the formation and thickening of an interface passive film of a phosphate-yttrium oxide coating, improves the self-repairing capacity of the passive film of the magnetic powder core in the environment with rare earth elements, reduces the content of Fe in a matrix along with the increase of the rare earth elements, promotes Fe to form intermetallic (FeSi) Al6 between dendrites, and the rare earth elements have a spheroidizing effect on intermetallic compounds containing iron and silicon to form compounds with iron, reduce the content of the Fe in an alpha (Al) matrix, improve the corrosion resistance of the passive film between dendrites and further improve the corrosion resistance of the magnetic powder core.
The invention adds 0.8-1.3% of Sc, 1.2-2.0% of Zr and 0.2-0.7% of Sr into the FeSiAl powder, reduces the hard brittleness of the FeSiAl powder and improves the magnetic property stability of the FeSiAl powder; through a phosphate-yttrium oxide composite coating process, the coating layer has strong corrosion resistance and high temperature resistance; the FeSiAlZrScSr magnetic powder core can obtain excellent soft magnetic performance by adopting a graded annealing heat treatment process at 450-500 ℃ and 930 +/-10 ℃.
Compared with the prior art, the invention has the beneficial effects that:
(1) The magnetic powder of the invention is added with rare earth elements of Zr, sc and Sr, and the Al in the Zr, sc and Sr and FeSiAl magnetic powder forms AlSr5 and Al 3 Zr and Al 3 The Sc new phase plays a certain role in modification and purification of the FeSiAl magnetic powder, can reduce the hard brittleness of the FeSiAl magnetic powder and improves the stability of the magnetic performance of the FeSiAl magnetic powder core.
(2) According to the invention, a phosphate-yttrium oxide composite coating process is adopted, the advantages of single coating of phosphate and yttrium oxide are taken into consideration, the thermal stability of a phosphate film layer is improved, and the hardness and brittleness of the yttrium oxide film layer are reduced; mixing 200 mesh of Y 2 O 3 Mixing the powder and phosphate-coated magnetic powder according to the proportion of 1: (22-33) the coating layers are uniformly mixed in proportion, so that the coating layers are uniformly coated on the surfaces of the magnetic powder, the insulating coating films are compact and have no cracking phenomenon, the resistivity of the magnetic powder core is effectively increased, and the power loss of the magnetic powder core is further reduced.
(3) The invention adopts a graded annealing process, so that the rare earth element forms a spheroidization effect on the intermetallic compound containing iron and silicon, and can form a compound with iron, thereby reducing the content of the iron element in an alpha (Al) matrix, improving the corrosion resistance of a passive film and further improving the corrosion resistance of the magnetic powder core.
Detailed Description
Exemplary embodiments, features and aspects of the invention are described below in conjunction with specific embodiments.
Specifically, the invention provides a FeSiAlZrScSr magnetic powder core and a preparation method thereof, and the preparation method comprises the following steps:
s1, pulverizing: preparing FeSiAl, sc, zr and Sr powders by adopting a gas atomization mode, mixing the prepared FeSiAl powders with the Sc, zr and Sr powders together, and annealing at high temperature of about 700-850 ℃ for 1.5-3 h under protective gas;
preparing materials: the grain size distribution of the alloy powder is-150 to +200 meshes, accounting for 10 +/-5 percent; minus 200 to plus 400 meshes, accounting for 70% +/-5%; and-300- +300 mesh, accounting for 20% +/-5%.
S2, phosphate coating: diluting phosphoric acid by absolute ethyl alcohol, adding a phosphoric acid diluent into mixed powder of FeSiAl and Sc, zr and Sr, adding yttrium oxide powder while stirring, performing surface treatment, wherein the adding amount of the phosphoric acid is 0.3wt%, the adding amount of the yttrium oxide is 0.2wt%, and heating and stirring are performed in a constant-temperature water bath at 50-70 ℃ until the mixed powder is dried;
s3, yttrium oxide coating: will Y 2 O 3 The powder and the phosphate-coated magnetic powder are uniformly mixed according to the proportion, and the addition amount of the yttrium oxide is 3.8 to 6.8 weight percent. Adding a binder, wherein the addition amount of the binder is 0.2-0.6 wt%, and uniformly stirring; heating the uniformly stirred powder at the temperature of between 70 and 160 ℃, and continuously stirring the powder until the powder is dried;
s4, adding a lubricant: adding a lubricant accounting for 0.6-1.0% of the weight of the powder, and uniformly mixing;
s5, press forming: pressing and molding the coated powder under a press machine to form a magnetic powder core;
s6, graded annealing: under protective gas, firstly putting the magnetic powder core into a furnace at 930 +/-10 ℃ for annealing, setting the heat preservation time to be 1.5-3 h and the heating rate to be 9 ℃/min; then reducing the temperature to 450-500 ℃, and setting the heat preservation time to 1-2 h;
the protective gas is argon.
The FeSiAlZrScSr powder comprises the following components in percentage by mass: si:9.0 to 9.6%, al:5.2 to 5.6%, zr: 1.2-2.0%, sc:0.8 to 1.3 percent, sr:0.2 to 0.7 percent, and the balance being Fe. The grain size distribution of the alloy powder is-150 to +200 meshes, accounting for 10 +/-5 percent; minus 200 to +400 meshes, accounting for 70% +/-5%; and-300- +300 mesh, accounting for 20% +/-5%.
The binder in step S3 is a sodium silicate solution.
The lubricant in step S4 is zinc stearate.
Table 1 raw materials of alloys in examples 1 to 9 are constituted by mass percentage
* The amount of yttrium oxide in Table 1 is the sum of the amounts of yttrium oxide added S2 and S3.
Example 1:
adopting a gas atomization mode to prepare FeSiAl powder, wherein the FeSiAl powder comprises the following components: si9.4%, al5.5% and the balance of Fe; under the protection gas, feSiAl powder is annealed for 1.5 to 3 hours at a high temperature of between 700 and 850 ℃, 200g of powder is weighed after annealing, and the particle size distribution of the alloy powder is required to be between-150 and +200 meshes and accounts for 10 +/-5 percent; minus 200 to plus 400 meshes, accounting for 70% +/-5%; and-300- +300 mesh, accounting for 20% +/-5%.
Adding phosphoric acid into the powder, wherein the addition amount of the phosphoric acid is 0.6g and accounts for 0.3 percent of the weight of the powder, and diluting with 100ml of absolute ethyl alcohol before use; adding the diluted phosphoric acid solution into FeSiAl powder, heating and stirring in a constant-temperature water bath at 50 ℃ until the powder is dried;
after the powder is cooled to room temperature, 0.6% zinc stearate lubricant is added, and the mixture is uniformly mixed by a screen to prepare pressed powder.
And pressing and molding the composite coating powder. The pressure is 12.5t/cm < 2 >, and the size of the magnetic ring blank is as follows: 20.30mm in outer diameter, 12.70mm in inner diameter and 5.50mm in height.
And (3) placing the magnetic powder core in an argon heat treatment furnace, and keeping the temperature at 850 ℃ for 1h.
And (3) soaking the prepared magnetic ring in a saturated NaCl solution for 2 hours, drying the magnetic ring in a vacuum furnace, and heating the magnetic ring at the high temperature of 800 ℃ for 10min.
Example 2:
the ingredients of this example are shown in Table 1, and FeSiAl, sc, zr and Sr powders were prepared by gas atomization. Mixing FeSiAl powder and Sc, zr and Sr powder together, annealing at high temperature of 700-850 ℃ for 1.5-3 h under protective gas, and weighing 200g of powder after annealing, wherein the particle size distribution of the alloy powder is required to be-150 to +200 meshes and accounts for 10 +/-5%; minus 200 to +400 meshes, accounting for 70% +/-5%; and-300- +300 mesh accounting for 20% +/-5%.
Phosphoric acid was added to the powder. The addition amount of phosphoric acid is 0.6g, which accounts for 0.3% of the weight of the powder, and the phosphoric acid is diluted by 100ml of absolute ethyl alcohol before use; adding the phosphoric acid diluent into FeSiAl powder, heating in a constant-temperature water bath at 50 ℃, adding yttrium oxide powder while stirring, wherein the addition amount of yttrium oxide is 0.2wt%, until the mixed powder is dried;
adding-150- +200 mesh Y to the powder coated with phosphoric acid 2 O 3 The powder, the addition of which is 7.6g and accounts for 3.8 percent of the weight of the powder, is mixed evenly; adding 1.2g of sodium silicate into the mixed powder, wherein the adding amount of the sodium silicate accounts for 0.60 percent of the weight of the powder, and diluting the powder with deionized water before use; will be added with Y 2 O 3 Uniformly stirring the mixed powder and sodium silicate, and reacting for 10 minutes; heating the mixed powder to 80 ℃ and continuously stirring until the mixed powder is dried;
and cooling the mixed powder to room temperature, adding 0.6% of zinc stearate lubricant, and uniformly mixing by using a screen to obtain pressed powder.
And pressing and molding the composite coating powder. The pressure is 12.5t/cm < 2 >, and the size of the magnetic ring blank is as follows: 20.30mm in outer diameter, 12.70mm in inner diameter and 5.50mm in height.
And (3) placing the magnetic powder core in an argon heat treatment furnace, and keeping the temperature at 850 ℃ for 1h.
And (3) soaking the prepared magnetic ring in a saturated NaCl solution for 2 hours, drying the magnetic ring in a vacuum furnace, and heating the magnetic ring at the high temperature of 800 ℃ for 10min.
Example 3:
the ingredients of this example are shown in Table 1.
The preparation method of the embodiment is the same as that of the embodiment 2.
Example 4:
the ingredients of this example are shown in Table 1.
The preparation method of the embodiment is the same as that of the embodiment 2.
Example 5:
the ingredients of this example are shown in Table 1.
The preparation method of the embodiment is the same as that of the embodiment 2.
Example 6:
the ingredients of this example are shown in Table 1.
The preparation method of the embodiment is the same as that of the embodiment 2.
Example 7:
the ingredients of this example are shown in Table 1.
The preparation method of the embodiment is the same as that of the embodiment 2.
Example 8:
the ingredients of this example are shown in Table 1.
The preparation method of the embodiment is the same as that of the embodiment 2.
Example 9:
the ingredients of this example are shown in Table 1.
The preparation method of the embodiment is the same as that of the embodiment 2.
In example 1, the rare earth elements Zr, sc, sr were not added, the grain sizes of Fe, si, al in the magnetic powder core were large, the grain deformation was not uniform during pressing, the movement of the magnetic domains was hindered, the coercive force was raised, and the loss of the magnetic powder core was increased. The loss after annealing is measured to be 180mW/cm 3 The magnetic permeability is 135H/m, the direct current superposition performance is 20.2A/m, and the self-corrosion potential and the current density are-220 mV and 4.765e respectively -6 uA·cm -2 。
In example 2, 1.2% of Zr, 0.8% of Sc, 0.2% of Sr, the synergistic effect of Zr, sc, sr and Fe, si, al in the magnetic powder core forms Al 3 Zr and Al 3 The new phases of Sc and the like play a certain role in modifying FeSiAl magnetic powder, reduce the resistance to movement between magnetic domains and strengthen the soft magnetic performance of the magnetic powder core, and the measured magnetic permeability is increased by 10 percent compared with that of the magnetic powder core in embodiment 1, the power loss is reduced by 22 percent compared with that of the magnetic powder core in embodiment 1, the superposition performance is increased by 15 percent, the self-corrosion potential is reduced by 13 percent, and the current density change is small.
In example 3, zr and Sc were increased by 50% and 37%, respectively, compared with those in example 2, and Sr was increased by two times. The purification and modification effects are further improved, the annealing temperature is increased to be beneficial to strengthening the soft magnetic performance of the magnetic powder core, the magnetic permeability is up to 160H/m, and the loss is as low as 128mW/cm 3 The direct current superposition performance is 28.1A/m, and the self-corrosion potential and the current density are-160 mV, 4.410e -6 uA·cm -2 。
In example 4, although the addition amount of each element was the largest as compared with the first three examples, the soft magnetic performance of the magnetic powder core was not the best. This is because when the amount of the rare earth element added exceeds a certain value, coarse AlSr5 and Al 3 Zr and Al 3 The Sc phase is greatly precipitated, so that the solid solubility of Zr, sc and Sr in an alloy matrix is reduced, and the soft magnetic performance and the corrosion performance of the magnetic powder core are reduced. The measured loss is 135mW/cm 3 Magnetic permeability of 153H/m, direct current superposition performance of 22.5A/m, self-corrosion potential and current density of-180 mV, 4.512e -6 uA·cm -2 。
In example 5, the yttrium oxide content was increased by 3% as compared with example 2, the thickness of the insulating layer of the magnetic powder core after coating treatment was increased, and the power loss was reduced as compared with example 2, and the loss of the magnetic powder core after powder selection, insulating coating, press molding, and graded annealing treatment was 130mW/cm 3 The magnetic permeability is 155H/m, the direct current superposition performance is 24.2A/m, and the self-corrosion potential and the current density are-170 mV and 3.432e respectively -6 uA·cm -2 。
In example 6, the contents of Zr, sc and Sr are increased compared with that in example 5, zr and Sc are respectively increased by 50% and 37% compared with that in example 5, and Sr is increased by two times. The purifying and modifying effects on the magnetic powder core are further improved, the crystal grains are obviously refined, and the loss of the magnetic powder core is 127mW/cm after the magnetic powder core is subjected to powder selection, insulating coating, compression molding and graded annealing treatment 3 The magnetic permeability is 160H/m, the direct current superposition performance is 27.8A/m, and the self-corrosion potential and the current density are-165 mV and 3.265e-6uA cm -2 。
In example 7, although the contents of Zr, sc, sr were increased as compared with example 6, the excessive addition of the rare earth element coarsened the magnetic powder crystal grain size to reduce the grain boundary area thereof, and when plastic deformation occurred, the deformation was not uniform, stress concentration was easily caused, and the magnetic performance of the magnetic powder core was lowered. The magnetic permeability is up to 152H/m and the loss is as low as 133mW/cm 3 The direct current superposition performance is 25.6A/m, and the self-corrosion potential and the current density are-168 mV and 3.382e respectively -6 uA·cm -2 。
In example 8Compared with the embodiment 6, the graded annealing process of firstly preserving heat for 1.5h at 930 ℃ and reducing the temperature to 450 ℃ for 1.5h is adopted, the process not only completely releases the internal stress in the magnetic powder core, but also promotes the enrichment of the second phase on the grain boundary and forms discontinuous corrosion channels in discontinuous distribution, so that the initiation of the micro-couple corrosion is reduced. After the magnetic powder core is subjected to powder selection, insulating coating, compression molding and graded annealing treatment, the loss is 128mW/cm 3 Magnetic permeability of 168H/m, direct current superposition performance of 28.1A/m, self-corrosion potential and current density of-160 mV and 3.110e- 6 uA·cm -2 。
In example 9, the low temperature heating temperature was increased by 50 ℃ as compared with example 8, and the grains easily coarsened at the low temperature holding temperature, and the purification and modification effects were further reduced, and the alignment of the magnetic moment direction of the magnetic domain in the magnet was disturbed, which was very detrimental to the magnetic properties of the magnetic powder core. The magnetic powder core is subjected to powder selection, insulating coating, press forming and graded annealing treatment, and the loss is 130mW/cm 3 The magnetic permeability is 163H/m, the direct current superposition performance is 27.5A/m, and the self-corrosion potential and the current density are-170 mV and 3.306e respectively -6 uA·cm -2 。
The magnetic properties of the samples prepared according to the present invention are shown in table 2 below.
TABLE 2 magnetic Properties of magnetic powder core
The present invention reduces the hard brittleness of FeSiAl powder by adding 0.8 to 1.3% of Sc, 1.2 to 2.0% of Zr and 0.2 to 0.7% of Sr to the FeSiAl powder, the tensile strength of the FeSiAl alloy is increased from 233MPa to 336MPa, and the elongation is increased from 4% to 22%; the magnetic property stability of the FeSiAl magnetic powder is improved, and the magnetic conductivity is stabilized to be about 160H/m; through a phosphate-yttrium oxide composite coating process, the corrosion resistance of the magnetic powder core is enhanced, the self-corrosion potential is increased from-220 mV to-160 mV, and the self-corrosion current density is increased from 4.765e -6 uA·cm -2 Reduced to 3.110e -6 uA·cm -2 (ii) a The high temperature resistance is enhanced, and a phosphate-yttrium oxide composite coating layer is 12No decomposition occurs at a high temperature of 00 ℃; the resistivity of the magnetic powder core is obviously improved, and the power loss is 128mW/cm 3 The loss is lower than that of the magnetic powder core without Zr, sc and Sr; the FeSiAlZrScSr magnetic powder core can obtain excellent soft magnetic performance after graded annealing at 930 +/-10 ℃ and 450-500 ℃.
Finally, it should be noted that the above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; various process schemes that are insubstantial different from the inventive concept are within the scope of the invention.
Claims (7)
1. A preparation method of FeSiAlZrScSr magnetic powder core is characterized in that:
firstly, rare earth elements of scandium, zirconium and strontium are added into FeSiAl powder, so that the hard brittleness of the FeSiAl magnetic powder can be reduced, and the magnetic property stability of a FeSiAl magnetic powder core is improved; secondly, by adopting a phosphate-yttrium oxide composite coating process, the coating layer enables the magnetic powder core to have strong corrosion resistance and high temperature resistance, effectively avoids the reduction of saturation magnetization and magnetic conductivity, and prepares the high-performance FeSiAl magnetic powder core under the condition of ensuring high magnetic conductivity;
the method specifically comprises the following steps:
s1, milling: preparing FeSiAl, sc, zr and Sr powders by adopting a gas atomization mode, mixing the prepared FeSiAl powders with Sc, zr and Sr powders together, and annealing at the high temperature of 700-850 ℃ for 1.5-3 h under protective gas;
s2, phosphate coating: diluting phosphoric acid by absolute ethyl alcohol, adding phosphoric acid diluent into the mixed powder obtained in the step S1, adding yttrium oxide powder while stirring, carrying out surface treatment, heating in a constant-temperature water bath at 50-70 ℃ while stirring until the mixed powder is dried;
s3, yttrium oxide coating: y of 200 meshes 2 O 3 Uniformly mixing the powder with the magnetic powder coated with the S2 phosphate according to a proportion, adding a binder, and uniformly stirring; heating the uniformly stirred powder at the temperature of between 70 and 160 ℃, and continuously stirring the powder until the powder is dried;
s4, adding a lubricant: adding a lubricant accounting for 0.6 to 1.0 percent of the weight of the powder, and uniformly mixing;
s5, press forming: pressing and molding the powder under a press machine to form a magnetic powder core;
s6, graded annealing: under protective gas, firstly putting the magnetic powder core into a furnace with the temperature of 930 +/-10 ℃ for annealing, setting the heat preservation time to be 1.5-3 h and the heating rate to be 9 ℃/min; then the temperature is reduced to 450-500 ℃, and the heat preservation time is set to 1-2 h.
2. The method of claim 1, wherein:
the particle size distribution of the mixed powder obtained in S1 is as follows: minus 150 to +200 meshes, accounting for 10 plus or minus 5 percent; minus 200 to +400 meshes, accounting for 70% +/-5%; minus 300 to plus 300 meshes, accounting for 20% +/-5%.
3. The production method according to claim 1 or 2, characterized in that:
the mixed powder obtained in the step S1 comprises the following components in percentage by mass: si9.0-9.6%, al5.2-5.6%, zr1.2-2.0%, sc0.8-1.3%, sr0.2-0.7%, and the balance Fe.
4. The method of claim 1, wherein:
in S2, the amount of phosphoric acid added was 0.3wt%, and the amount of yttrium oxide added was 0.2wt%.
5. The method of claim 1, wherein:
in S3, the addition amount of yttrium oxide is 3.8-6.8 wt%.
6. The method of claim 1, wherein:
the binder is sodium silicate solution; the lubricant is zinc stearate.
7. The method of claim 1, wherein:
in S3, Y 2 O 3 The mass ratio of the powder to the mixed powder obtained in S1 is1：(22-33)。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110988588.6A CN113674984B (en) | 2021-08-26 | 2021-08-26 | Preparation method of FeSiAlZrScSr magnetic powder core |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110988588.6A CN113674984B (en) | 2021-08-26 | 2021-08-26 | Preparation method of FeSiAlZrScSr magnetic powder core |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113674984A CN113674984A (en) | 2021-11-19 |
| CN113674984B true CN113674984B (en) | 2023-03-21 |
Family
ID=78546644
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110988588.6A Active CN113674984B (en) | 2021-08-26 | 2021-08-26 | Preparation method of FeSiAlZrScSr magnetic powder core |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113674984B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023223826A1 (en) * | 2022-05-18 | 2023-11-23 | 日本特殊陶業株式会社 | Insulated covered soft magnetic metal powder, magnetic dust core, electronic element, electronic device, electric motor and power generator |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010219359A (en) * | 2009-03-18 | 2010-09-30 | Dowa Electronics Materials Co Ltd | Metallic magnetic powder and method for manufacturing the same |
| CN102240802A (en) * | 2010-05-12 | 2011-11-16 | 亚利桑那大学董事会 | Metallic magnetic powder and manufacturing method of the same, magnetic painting, magnetic powder for magnetic therapy, and magnetic recording medium |
| JP2012104573A (en) * | 2010-11-08 | 2012-05-31 | Hitachi Chem Co Ltd | Powder for core, manufacturing method of the same, dust core using the same, and electromagnetic device |
| CN104217835A (en) * | 2013-06-05 | 2014-12-17 | 宋艳 | Method for manufacturing sendust core with effective magnetic permeability of 125 Henrys per meter |
| CN104505209A (en) * | 2014-12-22 | 2015-04-08 | 合肥工业大学 | Metal soft magnetic composite powder cores and preparation method thereof |
| CN105304308A (en) * | 2015-11-18 | 2016-02-03 | 临沂银凤电子科技股份有限公司 | Fe-Si-Al magnetic core preparation method and inorganic composite insulation coating material for magnetic core |
| CN106057460A (en) * | 2016-05-12 | 2016-10-26 | 横店集团东磁股份有限公司 | Preparation method for gas atomized metal magnetic powder core |
| CN108002703A (en) * | 2017-11-28 | 2018-05-08 | 贵州威顿晶磷电子材料股份有限公司 | A kind of lead-free glass powder with low melting point for amorphous powder core insulating wrapped and preparation method thereof |
| CN109273235A (en) * | 2018-09-26 | 2019-01-25 | 鲁东大学 | A kind of bivalve layer insulating coating method of metal soft magnetic composite material |
| CN111370214A (en) * | 2019-11-20 | 2020-07-03 | 横店集团东磁股份有限公司 | Method for preparing magnetic powder core from alloy composite powder |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP7124342B2 (en) * | 2018-02-28 | 2022-08-24 | セイコーエプソン株式会社 | Insulator-coated soft magnetic powder, method for producing insulator-coated soft magnetic powder, powder magnetic core, magnetic element, electronic device and moving object |
-
2021
- 2021-08-26 CN CN202110988588.6A patent/CN113674984B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010219359A (en) * | 2009-03-18 | 2010-09-30 | Dowa Electronics Materials Co Ltd | Metallic magnetic powder and method for manufacturing the same |
| CN102240802A (en) * | 2010-05-12 | 2011-11-16 | 亚利桑那大学董事会 | Metallic magnetic powder and manufacturing method of the same, magnetic painting, magnetic powder for magnetic therapy, and magnetic recording medium |
| JP2012104573A (en) * | 2010-11-08 | 2012-05-31 | Hitachi Chem Co Ltd | Powder for core, manufacturing method of the same, dust core using the same, and electromagnetic device |
| CN104217835A (en) * | 2013-06-05 | 2014-12-17 | 宋艳 | Method for manufacturing sendust core with effective magnetic permeability of 125 Henrys per meter |
| CN104505209A (en) * | 2014-12-22 | 2015-04-08 | 合肥工业大学 | Metal soft magnetic composite powder cores and preparation method thereof |
| CN105304308A (en) * | 2015-11-18 | 2016-02-03 | 临沂银凤电子科技股份有限公司 | Fe-Si-Al magnetic core preparation method and inorganic composite insulation coating material for magnetic core |
| CN106057460A (en) * | 2016-05-12 | 2016-10-26 | 横店集团东磁股份有限公司 | Preparation method for gas atomized metal magnetic powder core |
| CN108002703A (en) * | 2017-11-28 | 2018-05-08 | 贵州威顿晶磷电子材料股份有限公司 | A kind of lead-free glass powder with low melting point for amorphous powder core insulating wrapped and preparation method thereof |
| CN109273235A (en) * | 2018-09-26 | 2019-01-25 | 鲁东大学 | A kind of bivalve layer insulating coating method of metal soft magnetic composite material |
| CN111370214A (en) * | 2019-11-20 | 2020-07-03 | 横店集团东磁股份有限公司 | Method for preparing magnetic powder core from alloy composite powder |
Non-Patent Citations (1)
| Title |
|---|
| 铁硅铬合金磁粉表面包覆及其对磁粉芯性能的影响;王东等;《磁性材料及器件》(第03期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113674984A (en) | 2021-11-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111101057B (en) | Soft magnetic alloy strip for ultralow-temperature magnetic shielding and preparation method thereof | |
| WO2010104067A1 (en) | Non-oriented magnetic steel sheet and method for producing the same | |
| CN112962028B (en) | Strong magnetic orientation high-silicon steel ultra-thin strip and preparation method thereof | |
| CN109727742A (en) | A kind of low heavy rare earth NdFeB material and preparation method thereof | |
| EP3572548B1 (en) | Iron-based amorphous alloy and preparation method therefor | |
| CN113674984B (en) | Preparation method of FeSiAlZrScSr magnetic powder core | |
| CN111564273A (en) | FeNi soft magnetic alloy with low cost and high saturation magnetic induction intensity and preparation method thereof | |
| CN111020131A (en) | Annealing process of silicon steel iron core | |
| JPS62180014A (en) | Non-oriented electrical sheet having low iron loss and superior magnetic flux density and its manufacture | |
| KR920004678B1 (en) | METHOD FOR MANUFACTURING Ni-Fe ALLOY SHEET HAVING EXCELLENT DC MAGNETIC PROPERTY AND EXCELLENT AC MAGNETIC PROPERTY | |
| JP2011202213A (en) | Soft magnetic powder for magnetic green compact, magnetic green compact using the same and method for producing the same | |
| JP7381123B2 (en) | Multi-component FeCoSiM soft magnetic alloy and its manufacturing method | |
| CN108950434B (en) | Iron-based amorphous strip with low excitation power and preparation method thereof | |
| JP2560579B2 (en) | Method for manufacturing high silicon steel sheet having high magnetic permeability | |
| JP6191774B2 (en) | Raw powder for soft magnetic powder and soft magnetic powder for dust core | |
| JP3094727B2 (en) | Powder for magnetic shielding | |
| CN113838620A (en) | Rare earth permanent magnetic material and preparation method thereof | |
| KR950013285B1 (en) | Process for production thin magnetic steel plate having high ptrmeability | |
| CN111341513B (en) | High-magnetic-performance neodymium iron boron magnet and preparation method thereof | |
| JP3094728B2 (en) | Powder for magnetic shielding | |
| JP5826284B2 (en) | Wire rods, steel wires having excellent magnetic properties, and methods for producing them | |
| JPH0477067B2 (en) | ||
| JP2004146563A (en) | Compound magnetic material | |
| JPH03122236A (en) | Ni-fe serite high permeability magnetic alloy | |
| JPH0580122B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |