阅读说明：本技术 一种一体式共烧电感及其制备方法与应用 (Integrated co-fired inductor and preparation method and application thereof ) 是由 张丛 韩相华 金志洪 王林科 张宁 于 2020-12-24 设计创作，主要内容包括：本发明涉及一种一体式共烧电感及其制备方法与应用,所述制备方法包括：导体穿设于改性磁粉中部,然后在300-1000MPa下进行模压成型；保护气氛下对所述模压成型后所得产品进行热处理,得到所述一体式共烧电感。电感由磁粉经过模压成型制备,提高了直流叠加特性；且导体与磁粉一体成型,所得一体式共烧电感的体积小,空间率用率高；导体与磁粉共同进行热处理,使所得电感的结构更加稳定,功耗更低；更进一步的,本发明所述一体式共烧电感能够在300-1000MPa下模压成型,所需压力较低。(The invention relates to an integrated co-fired inductor and a preparation method and application thereof, wherein the preparation method comprises the following steps: the conductor penetrates through the middle part of the modified magnetic powder and then is subjected to compression molding under the pressure of 300-; and carrying out heat treatment on the product obtained after compression molding under a protective atmosphere to obtain the integrated co-fired inductor. The inductor is prepared by compression molding of magnetic powder, so that the direct current superposition characteristic is improved; the conductor and the magnetic powder are integrally formed, so that the obtained integrated co-fired inductor is small in size and high in space efficiency; the conductor and the magnetic powder are subjected to heat treatment together, so that the obtained inductor is more stable in structure and lower in power consumption; furthermore, the integrated co-fired inductor can be molded under the pressure of 300-1000MPa, and the required pressure is low.)

1. A preparation method of an integrated co-fired inductor is characterized by comprising the following steps:

(1) the conductor penetrates through the middle part of the modified magnetic powder and then is subjected to compression molding under the pressure of 300-;

(2) and (3) carrying out heat treatment on the product obtained after compression molding in the step (1) under a protective atmosphere to obtain the integrated co-fired inductor.

2. The method of manufacturing according to claim 1, wherein the compression molding method of step (1) includes two-way compression.

3. The production method according to claim 1 or 2, wherein the temperature rise rate of the heat treatment of step (2) is 3 to 8 ℃/min;

preferably, the temperature of the heat treatment in the step (2) is 300-900 ℃;

preferably, the heat treatment in the step (2) has the heat preservation time of 20-40 min;

preferably, the gas used in the protective atmosphere in step (2) includes any one or a combination of at least two of nitrogen, argon, helium or hydrogen.

4. The production method according to any one of claims 1 to 3, wherein the modified magnetic powder of step (1) is a soft magnetic material modified by an insulating coating;

preferably, the soft magnetic material comprises any one or a combination of at least two of a metal soft magnetic material, an amorphous soft magnetic material or a nanocrystalline soft magnetic material;

preferably, the metal soft magnetic material comprises any one or a combination of at least two of iron powder, ferrosilicon powder, iron-silicon-chromium powder, iron-silicon-aluminum powder, iron-nickel-molybdenum powder or hydroxyl iron powder;

preferably, the preparation method of the soft magnetic material comprises any one of gas atomization, water atomization or crushing;

preferably, the soft magnetic material includes a combination of at least two of an ultra fine soft magnetic material, a fine powder soft magnetic material, a medium powder soft magnetic material, or a coarse powder soft magnetic material;

preferably, the particle size D50 of the ultra-fine soft magnetic material is <3 μm;

preferably, the particle size of the fine powder soft magnetic material D10>4 μm, and D90<8 μm;

preferably, the particle size of the medium powder soft magnetic material D10 is more than 8 μm, and D90 is less than 19 μm;

preferably, the coarse powder soft magnetic material has a particle size D10>18 μm, and D90<100 μm.

5. The method of claim 4, wherein the modifying of the insulating coating comprises the steps of:

(i) passivating the soft magnetic material to obtain a passivated soft magnetic material;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i) to obtain an insulated soft magnetic material;

(iii) and (3) mixing a binder, a release agent and the insulated soft magnetic material obtained in the step (2) to complete the insulation coating modification.

6. The method according to claim 5, wherein the passivation treatment of step (i) is: mixing a soft magnetic material and a passivating agent;

preferably, the passivating agent comprises phosphoric acid and/or aluminium dihydrogen phosphate;

preferably, the addition amount of the passivating agent is 0.01-2 wt% of the soft magnetic material;

preferably, the temperature of the passivation treatment of step (i) is 100-;

preferably, the insulation treatment of step (ii) is: mixing an insulating agent with a passivated soft magnetic material;

preferably, the insulating agent comprises any one of alumina, kaolin, silica or magnesia or a combination of at least two thereof;

preferably, the addition amount of the insulating agent is 0.02-2.3 wt% of the passivated soft magnetic material;

preferably, the addition amount of the binder is 0.2 to 5 wt% of the insulating soft magnetic material;

preferably, the addition amount of the release agent is 0.1 to 1.5 wt% of the insulating soft magnetic material;

preferably, the insulating coating modification further comprises step (iv) after step (iii): granulating to obtain the modified magnetic powder;

preferably, the particle size after granulation is 30 to 200 mesh.

7. The production method according to any one of claims 1 to 6, characterized by comprising the steps of:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent comprises phosphoric acid and/or aluminum dihydrogen phosphate; the addition amount of the passivating agent is 0.01-2 wt% of the soft magnetic material; the temperature of the passivation treatment is 100-150 ℃;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): (ii) mixing an insulating agent with the passivated soft magnetic material obtained in step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 0.02-2.3 wt% of the passivated soft magnetic material;

(iii) mixing a binder, a release agent and the insulated soft magnetic material obtained in the step (2), wherein the addition amount of the binder is 0.2-5 wt% of the insulated soft magnetic material; the addition amount of the release agent is 0.1-1.5 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with particle size of 30-200 meshes;

(1) the conductor penetrates through the middle part of the modified magnetic powder and then is pressed bidirectionally under the pressure of 300-;

(2) and (3) under a protective atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 900 ℃ at the heating rate of 3-8 ℃/min, and preserving heat for 20-40min to obtain the integrated co-fired inductor.

8. An integrated co-fired inductor prepared by the preparation method of any one of claims 1 to 7.

9. The integrated co-fired inductor of claim 8, wherein the conductor comprises any one of a copper conductor, an aluminum conductor, or a silver conductor;

preferably, the shape of the conductor comprises a cylinder or a square.

10. Use of an integral co-fired inductor as claimed in claim 8 or 9 as a magnetic component.

Technical Field

The invention belongs to the technical field of electromagnetism, relates to an inductor, and particularly relates to an integrated co-fired inductor and a preparation method and application thereof.

Background

The integrally formed inductor comprises a base body and a winding body, wherein the base is formed by embedding the winding body into metal magnetic powder through die casting, the structural characteristics of the integrally formed inductor meet the development requirement of continuous miniaturization of electronic products, and the integrally formed inductor is widely applied to computer main boards, display cards, industrial personal computers, servers, collection, tablet personal computers and automobile electronic products; the integrated inductor has high saturation magnetic flux density, has the main functions of filtering, oscillating, delaying, trapping and the like in a circuit, and also has the functions of screening signals, filtering noise, stabilizing current, inhibiting interference of electromagnetic waves and the like, so that the miniature inductor becomes a key device in the high-end electronic manufacturing industry, and electronic devices are increasingly developed to miniaturization, high performance and high speed along with the progress of electronic manufacturing fields such as automation control technology, intelligent terminals and the like.

The existing integrally formed inductor comprises a base body and a winding body, wherein the base body is formed by embedding the winding body into metal magnetic powder through die-casting, the winding is usually a coil coated by a single-layer or multi-layer paint coating, the inductor prepared by the method can only be used for curing glue in magnetic powder through low-temperature baking, the strength of the inductor is improved, the internal stress during the forming of the inductor cannot be released, the power consumption is high, and the inductor is suitable for the low-frequency condition. The loss of the metal magnetic powder is mainly composed of hysteresis loss and eddy current loss, and the hysteresis loss is increased while the eddy current loss is reduced, so that the problem is difficult to solve simultaneously.

CN 104493162a discloses a ferrite inductor integrated forming process, in which ferrite material is separately sintered in a solid phase, then crushed, mixed and integrally formed with a copper conductor to form a blank, then the blank is sintered at a low temperature, and finally a rear-end processing procedure is performed to obtain a required inductor finished product. However, the inductor obtained by the ferrite inductor integrated forming process has low anti-saturation capacity, and needs to be improved by cutting an air gap, so that the volume of the obtained inductor is large, and the inductor does not accord with the trend of miniaturization of devices and the practical application of the obtained inductor.

CN 110718359a discloses a manufacturing structure and method of a surface mount integrated inductor, the method includes the following steps: pre-rolling a hollow built-in coil; preforming a mixture of magnetic powder and thermosetting numerical values into two groups of completely same pressing plate main bodies, wherein the pressing plate main bodies are provided with pressing surfaces, and the pressing surfaces are characterized in that the two sides are high, and the middle is low; in a forming die, two groups of pressing plate main bodies are respectively placed right above and right below a coil, the pressing surface of each pressing plate main body faces towards the built-in coil, two stages of the built-in coils need to exceed the range of two end parts of each pressing plate main body respectively, and then a blank body is formed by pressurization and heating; two stages of the built-in coil are exposed outside the blank after molding, and after the insulators of the two stages are removed, external electrodes are formed at two ends of the blank. The air gap is arranged between the inductance winding and the magnet, so that the whole body is not compact, and the volume utilization rate is not as high as that of the integral molding.

In view of the above, it is desirable to provide an inductor suitable for use under high current and high frequency conditions, and having a high space utilization.

Disclosure of Invention

The invention aims to provide an integrated co-fired inductor, a preparation method and application thereof.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the invention provides a method for preparing an integrated co-fired inductor, which comprises the following steps:

(1) the conductor penetrates through the middle part of the modified magnetic powder and then is subjected to compression molding under the pressure of 300-;

(2) and (3) carrying out heat treatment on the product obtained after compression molding in the step (1) under a protective atmosphere to obtain the integrated co-fired inductor.

The invention adopts the low pressure of 300-1000MPa to carry out compression molding on the modified magnetic powder penetrated with the conductor, thereby prolonging the service life of the grinding tool, effectively preventing the conductor from being broken and effectively avoiding the problem of short circuit between coils. And the product after compression molding is subjected to heat treatment, so that the stress generated by compression molding can be effectively eliminated, the structure is more stable, and the magnetic conductivity and the Q value of the obtained integrated co-fired inductor are improved, thereby reducing the power consumption. Furthermore, because the conductor and the magnetic powder are integrally formed, the obtained integrated co-fired inductor has small volume and high space utilization rate, and is convenient for industrial application of the integrated co-fired inductor.

Preferably, the compression molding method of step (1) comprises two-way compression.

The invention adopts a bidirectional pressing method to carry out compression molding, so that the compression molded magnet has uniform density, is not easy to crack, and has good conductor centering degree.

The pressure for the press molding in the present invention is 300-1000MPa, and may be, for example, 300MPa, 400MPa, 500MPa, 600MPa, 700MPa, 800MPa, 900MPa or 1000MPa, but is not limited to the values listed, and other values not listed in the numerical range are also applicable.

Preferably, the heating rate of the heat treatment in step (2) is 3-8 deg.C/min, such as 3 deg.C/min, 4 deg.C/min, 5 deg.C/min, 6 deg.C/min, 7 deg.C/min or 8 deg.C/min, but not limited to the values listed, and other values not listed in the range of values are equally applicable.

Preferably, the temperature of the heat treatment in step (2) is 300-900 ℃, for example, 300 ℃, 400 ℃, 500 ℃, 600 ℃, 700 ℃, 800 ℃ or 900 ℃, but not limited to the recited values, and other unrecited values within the range of values are equally applicable.

Preferably, the heat treatment in step (2) is carried out for a holding time of 20-40min, such as 20min, 25min, 30min, 35min or 40min, but not limited to the recited values, and other values not recited in the range of values are also applicable.

The invention can eliminate the stress generated during compression molding through heat treatment, thereby improving the magnetic conductivity and Q value of the obtained integrated co-fired inductor, stabilizing the structure of the integrated co-fired inductor and reducing the power consumption.

Preferably, the gas used in the protective atmosphere in step (2) comprises any one or a combination of at least two of nitrogen, argon, helium or hydrogen; typical but non-limiting combinations include a combination of nitrogen and argon, a combination of argon and helium, a combination of nitrogen and hydrogen, a combination of argon and hydrogen, a combination of helium and hydrogen, or a combination of nitrogen, argon, helium and hydrogen.

Preferably, the modified magnetic powder in the step (1) is a soft magnetic material modified by insulation coating.

Preferably, the soft magnetic material comprises any one or a combination of at least two of a metal soft magnetic material, an amorphous soft magnetic material or a nanocrystalline soft magnetic material; typical but non-limiting combinations include combinations of metallic soft magnetic materials with amorphous soft magnetic materials, amorphous soft magnetic materials with nanocrystalline soft magnetic materials, metallic soft magnetic materials with nanocrystalline soft magnetic materials, or metallic soft magnetic materials, amorphous soft magnetic materials with nanocrystalline soft magnetic materials.

Preferably, the metal soft magnetic material comprises any one or a combination of at least two of iron powder, ferrosilicon powder, iron-silicon-chromium powder, iron-silicon-aluminum powder, iron-nickel-molybdenum powder or hydroxyl iron powder; typical but non-limiting combinations include combinations of iron powder and ferrosilicon powder, ferrosilicon powder and ferrosilicon chromium powder, ferrosilicon chromium powder and ferrosilicon aluminum powder, ferrosilicon aluminum powder and ferronickel powder, ferronickel molybdenum powder and hydroxyl iron powder, ferrosilicon powder and hydroxyl iron powder, and ferrosilicon chromium powder and hydroxyl iron powder.

Preferably, the composition of the amorphous soft magnetic material and the nanocrystalline soft magnetic material includes but is not limited to any one of FeSiBCr, FeCuNbSiB or FeSiB.

Preferably, the preparation method of the soft magnetic material comprises any one of gas atomization, water atomization or crushing or a combination of at least two of the gas atomization, the water atomization and the crushing.

The soft magnetic material can be prepared by gas atomization, water atomization or crushing, so that the preparation method has low requirement on the morphology of the soft magnetic iron powder.

Preferably, the soft magnetic material includes a combination of at least two of an ultra fine soft magnetic material, a fine powder soft magnetic material, a medium powder soft magnetic material, or a coarse powder soft magnetic material.

Preferably, the particle size D50 of the ultra-fine soft magnetic material is <3 μm, and may be, for example, 1 μm, 1.2 μm, 1.5 μm, 1.8 μm, 2 μm, 2.4 μm, 2.5 μm, 2.7 μm or 2.8 μm, but is not limited to the recited values, and other values not recited in the numerical range are equally applicable.

Preferably, the particle size D10 of the fine powder soft magnetic material is more than 4 μm, for example, 4.2 μm, 4.5 μm, 4.8 μm, 5 μm, 5.2 μm or 5.5 μm, but is not limited to the values recited, and other values not recited in the range of values are equally applicable; and D90<8 μm, for example 6.5 μm, 6.8 μm, 7 μm, 7.2 μm, 7.5 μm, 7.7 μm or 7.9 μm, but is not limited to the values recited, and other values not recited in the range of values are equally applicable.

Preferably, the particle size of the medium powder soft magnetic material D10 is more than 8 μm, and D90 is less than 19 μm;

preferably, the coarse powder soft magnetic material has a particle size D10>18 μm, and D90<100 μm.

Preferably, the superfine soft magnetic material accounts for 15-37 wt% of the soft magnetic material, and may be, for example, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt%, 35 wt%, 36 wt%, or 37 wt%, but is not limited to the recited values, and other values in the range of values are also applicable.

The proportion of the fine powder soft magnetic material in the soft magnetic material is 20 to 60 wt%, and may be, for example, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, or 60 wt%, but is not limited to the recited values, and other values not recited in the range of values are also applicable.

The proportion of the medium-powder soft magnetic material in the soft magnetic material is 3 to 50 wt%, and may be, for example, 3 wt%, 5 wt%, 10 wt%, 15 wt%, 20 wt%, 30 wt%, 40 wt%, or 50 wt%, but is not limited to the recited values, and other values not recited in the range of values are also applicable.

The proportion of the coarse powder soft magnetic material in the soft magnetic material is 10 to 30 wt%, for example 10 wt%, 15 wt%, 20 wt%, 25 wt% or 30 wt%, but is not limited to the recited values, and other values not recited in the range of values are also applicable.

The invention grades the soft magnetic material according to the grain size of the soft magnetic material, so that the soft magnetic material with smaller grain size can be filled into the pores of the soft magnetic material with larger grain size, thereby improving the magnetic density; and the magnetic conductivity is in direct proportion to the magnetic density, so that the gaps of the soft magnetic material are reduced, and the magnetic conductivity of the obtained inductor is effectively improved. And the eddy current loss can be effectively reduced by reasonably reducing the particle size of the soft magnetic material.

Preferably, the insulating coating modification comprises the following steps:

(i) passivating the soft magnetic material to obtain a passivated soft magnetic material;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i) to obtain an insulated soft magnetic material;

(iii) and (3) mixing a binder, a release agent and the insulated soft magnetic material obtained in the step (2) to complete the insulation coating modification.

Preferably, the passivation treatment of step (i) is: mixing the soft magnetic material with a passivating agent.

Preferably, the passivating agent comprises phosphoric acid and/or aluminium dihydrogen phosphate.

Preferably, the passivating agent is added in an amount of 0.01 to 2 wt.%, for example 0.01 wt.%, 0.05 wt.%, 0.1 wt.%, 0.5 wt.%, 1 wt.%, 1.2 wt.%, 1.5 wt.%, 1.8 wt.% or 2 wt.%, based on the soft magnetic material, but not limited to the recited values, and other values not recited in the numerical range are equally applicable.

Preferably, the temperature of the passivation treatment in step (i) is 100-.

Preferably, the insulation treatment of step (ii) is: an insulator is mixed with the passivated soft magnetic material.

Preferably, the insulating agent comprises any one of alumina, kaolin, silica or magnesia or a combination of at least two thereof; typical but non-limiting combinations include combinations of alumina and silica, silica and magnesia, alumina and magnesia, or alumina, kaolin, silica and magnesia.

Preferably, the insulating agent is added in an amount of 0.02-2.3 wt.%, for example 0.02 wt.%, 0.05 wt.%, 0.1 wt.%, 0.3 wt.%, 0.5 wt.%, 0.8 wt.%, 1 wt.%, 1.2 wt.%, 1.5 wt.%, 1.8 wt.%, 2 wt.%, 2.1 wt.% or 2.3 wt.% of the passivated soft magnetic material, but not limited to the recited values, and other values not recited within the numerical ranges are equally applicable.

Preferably, the binder is added in an amount of 0.2 to 5 wt% of the insulating soft magnetic material, for example, may be 0.2 wt%, 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, or 5 wt%, but is not limited to the recited values, and other values not recited within the range of values are also applicable.

The adhesive is a conventional adhesive in the field, and the performance of the obtained integrated co-fired inductor is slightly influenced by different types of adhesives, so that the invention is not particularly limited.

Preferably, the release agent is added in an amount of 0.1 to 1.5 wt% of the insulating soft magnetic material, and may be, for example, 0.1 wt%, 0.3 wt%, 0.5 wt%, 0.7 wt%, 0.8 wt%, 1 wt%, 1.2 wt%, or 1.5 wt%, but is not limited to the enumerated values, and other values not enumerated within the numerical range are equally applicable.

Preferably, the insulating coating modification further comprises step (iv) after step (iii): and (4) granulating to obtain the modified magnetic powder.

Preferably, the obtained granules have a particle size of 30 to 200 mesh, for example, 30 mesh, 40 mesh, 50 mesh, 80 mesh, 100 mesh, 120 mesh, 150 mesh, 160 mesh, 180 mesh or 200 mesh, but not limited to the values listed, and other values not listed in the numerical range are also applicable.

The particle size of the granulated powder is 30-200 meshes, which means that the particle size of the obtained modified magnetic powder is 30-200 meshes.

As a preferable technical solution of the preparation method of the first aspect of the present invention, the preparation method comprises the steps of:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent comprises phosphoric acid and/or aluminum dihydrogen phosphate; the addition amount of the passivating agent is 0.01-2 wt% of the soft magnetic material; the temperature of the passivation treatment is 100-150 ℃;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): (ii) mixing an insulating agent with the passivated soft magnetic material obtained in step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 0.02-2.3 wt% of the passivated soft magnetic material;

(iii) mixing a binder, a release agent and the insulated soft magnetic material obtained in the step (2), wherein the addition amount of the binder is 0.2-5 wt% of the insulated soft magnetic material; the addition amount of the release agent is 0.1-1.5 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with particle size of 30-200 meshes;

(1) the conductor penetrates through the middle part of the modified magnetic powder and then is pressed bidirectionally under the pressure of 300-;

(2) and (3) under a protective atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 900 ℃ at the heating rate of 3-8 ℃/min, and preserving heat for 20-40min to obtain the integrated co-fired inductor.

In a second aspect, the invention provides the integral co-fired inductor prepared by the preparation method of the first aspect.

Preferably, the conductor includes any one of a copper conductor, an aluminum conductor, or a silver conductor.

Preferably, the shape of the conductor comprises a cylinder or a square.

The conductor of the integrated co-fired inductor is positioned in the middle of the integrated co-fired inductor, and a magnetic field is generated when the conductor is electrified. The magnitude and direction of the magnetic field and current determine the magnitude of the inductance value, and therefore, those skilled in the art can reasonably select the material and cross section of the conductor according to actual needs.

In a third aspect, the invention provides a use of the integrated co-fired inductor according to the second aspect as a magnetic element.

Compared with the prior art, the invention has the following beneficial effects:

the invention adopts the low pressure of 300-1000MPa to carry out compression molding on the modified magnetic powder penetrated with the conductor, thereby prolonging the service life of the grinding tool, effectively preventing the conductor from being broken and effectively avoiding the problem of short circuit between coils. And the product after compression molding is subjected to heat treatment, so that the stress generated by compression molding can be effectively eliminated, the structure is more stable, and the magnetic conductivity and the Q value of the obtained integrated co-fired inductor are improved, thereby reducing the power consumption. Furthermore, because the conductor and the magnetic powder are integrally formed, the obtained integrated co-fired inductor has small volume and high space utilization rate, and is convenient for industrial application of the integrated co-fired inductor.

Drawings

Fig. 1 is a schematic structural diagram of the integrated co-fired inductor obtained in the present invention.

Wherein: 1, a magnet; 2, a conductor.

Detailed Description

The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

Example 1

The embodiment provides a preparation method of an integrated co-fired inductor, which comprises the following steps:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent is phosphoric acid; the addition amount of the passivating agent is 1 wt% of the soft magnetic material; the temperature of the passivation treatment is 120 ℃;

the soft magnetic material is gas atomized iron nickel powder (FeNi 50); the proportion of the superfine soft magnetic material in the soft magnetic material is 20 wt%, the proportion of the fine soft magnetic material is 50 wt%, and the proportion of the medium soft magnetic material is 30 wt%;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): (ii) mixing an insulating agent with the passivated soft magnetic material obtained in step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 0.4 wt% of the passivated soft magnetic material; the insulating agent is kaolin;

(iii) mixing a binder and a release agent with the insulated soft magnetic material obtained in the step (2); the adhesive is organic silicon resin (KX605), and the addition amount of the adhesive is 1.5 wt% of the insulating soft magnetic material; the release agent is calcium stearate, and the addition amount of the release agent is 0.3 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with the particle size of 100 meshes;

(1) the conductor 2 penetrates through the middle part of the modified magnetic powder and then is subjected to bidirectional pressing under 800 MPa; the conductor 2 is a cuboid copper sheet, and the length, the width and the height are 20 multiplied by 2.2 multiplied by 0.35 mm; the size of the magnet 1 obtained by punching is 13.5 × 4.9 × 3 mm;

(2) and (3) under a hydrogen atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 730 ℃ at a heating rate of 5 ℃/min, and preserving heat for 30min to obtain the integrated co-fired inductor shown in the figure 1.

Example 2

The embodiment provides a method for preparing an integrated co-fired inductor, which is the same as the embodiment 1 except that the pressure of the bidirectional pressing in the step (1) is 300 MPa.

Example 3

The embodiment provides a method for preparing an integrated co-fired inductor, which is the same as the embodiment 1 except that the pressure of the bidirectional pressing in the step (1) is 1000 MPa.

Example 4

The embodiment provides a preparation method of an integrated co-fired inductor, which comprises the following steps:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent is aluminum dihydrogen phosphate; the addition amount of the passivating agent is 0.01 wt% of the soft magnetic material; the temperature of the passivation treatment is 150 ℃;

the composition of the soft magnetic material is the same as that of example 1;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): (ii) mixing an insulating agent with the passivated soft magnetic material obtained in step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 0.02 wt% of the passivated soft magnetic material; the insulating agent is kaolin;

(iii) mixing a binder and a release agent with the insulated soft magnetic material obtained in the step (2); the adhesive is organic silicon resin (KX605), and the addition amount of the adhesive is 0.2 wt% of the insulating soft magnetic material; the release agent is calcium stearate, and the addition amount of the release agent is 0.1 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with the particle size of 200 meshes;

(1) the conductor 2 penetrates through the middle part of the modified magnetic powder and then is subjected to bidirectional pressing under 600 MPa; the conductor 2 is a cuboid copper sheet, and the length, the width and the height are 20 multiplied by 2.2 multiplied by 0.35 mm; the size of the magnet 1 obtained by punching is 13.5 × 4.9 × 3 mm;

(2) and (3) under a hydrogen atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 600 ℃ at a heating rate of 3 ℃/min, and preserving heat for 40min to obtain the integrated co-fired inductor shown in the figure 1.

Example 5

The embodiment provides a preparation method of an integrated co-fired inductor, which comprises the following steps:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent is aluminum dihydrogen phosphate; the addition amount of the passivating agent is 2 wt% of the soft magnetic material; the temperature of the passivation treatment is 100 ℃;

the composition of the soft magnetic material is the same as that of example 1;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): (ii) mixing an insulating agent with the passivated soft magnetic material obtained in step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 2.3 wt% of the passivated soft magnetic material; the insulating agent is kaolin;

(iii) mixing a binder and a release agent with the insulated soft magnetic material obtained in the step (2); the binder is organic silicon resin (HJY686), and the addition amount of the binder is 5 wt% of the insulating soft magnetic material; the release agent is calcium stearate, and the addition amount of the release agent is 1.5 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with the particle size of 30 meshes;

(1) the conductor 2 penetrates through the middle part of the modified magnetic powder and then is subjected to bidirectional pressing under 400 MPa; the conductor 2 is a cuboid copper sheet, and the length, the width and the height are 20 multiplied by 2.2 multiplied by 0.35 mm; the size of the magnet 1 obtained by punching is 13.5 × 4.9 × 3 mm;

(2) and (3) under a hydrogen atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 900 ℃ at a heating rate of 8 ℃/min, and preserving heat for 20min to obtain the integrated co-fired inductor shown in the figure 1.

Example 6

The embodiment provides a preparation method of an integrated co-fired inductor, which comprises the following steps:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent is aluminum dihydrogen phosphate; the addition amount of the passivating agent is 2 wt% of the soft magnetic material; the temperature of the passivation treatment is 120 ℃;

the soft magnetic material is gas atomized iron-silicon-aluminum powder (sendust) and gas atomized iron-nickel powder (FeNi 50); the proportion of the superfine air-atomized iron-nickel powder in the soft magnetic material is 15 wt%, the proportion of the fine powder air-atomized iron-nickel powder is 25 wt%, and the proportion of the medium powder air-atomized iron-silicon-aluminum powder is 50 wt%; the proportion of the coarse powder gas atomized ferro-silicon-aluminum powder is 10 wt%;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): mixing an insulating agent with the passivated soft magnetic material (HJY686) obtained in the step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 0.1 wt% of the passivated soft magnetic material; the insulating agent consists of kaolin and magnesium oxide in a mass ratio of 1: 1;

(iii) mixing a binder and a release agent with the insulated soft magnetic material obtained in the step (2); the binder is organic silicon resin, and the addition amount of the binder is 0.3 wt% of the insulating soft magnetic material; the release agent is calcium stearate, and the addition amount of the release agent is 0.3 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with the particle size of 100 meshes;

(1) the conductor 2 penetrates through the middle part of the modified magnetic powder and then is subjected to bidirectional pressing under 600 MPa; the conductor 2 is a cuboid copper sheet, and the length, the width and the height are 20 multiplied by 2.2 multiplied by 0.35 mm; the size of the magnet 1 obtained by punching is 13.5 × 4.9 × 3 mm;

(2) and (3) under the nitrogen atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 700 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 35min to obtain the integrated co-fired inductor shown in the figure 1.

Example 7

The embodiment provides a preparation method of an integrated co-fired inductor, which comprises the following steps:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent is aluminum dihydrogen phosphate; the addition amount of the passivating agent is 1.6 wt% of the soft magnetic material; the temperature of the passivation treatment is 120 ℃;

the soft magnetic material is gas atomized ferrosilicon aluminum powder (sendust), gas atomized ferrosilicon powder (72 ferrosilicon powder) and gas atomized ferronickel powder (FeNi 50); the soft magnetic material contains 25 wt% of superfine air-atomized iron-silicon powder, 20 wt% of fine powder air-atomized iron-silicon-aluminum powder and 40 wt% of medium powder air-atomized iron-silicon-aluminum powder; the proportion of the coarse powder gas atomized iron-nickel powder is 15 wt%;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): (ii) mixing an insulating agent with the passivated soft magnetic material obtained in step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 0.3 wt% of the passivated soft magnetic material; the insulating agent consists of kaolin and alumina in a mass ratio of 1: 1;

(iii) mixing a binder and a release agent with the insulated soft magnetic material obtained in the step (2); the adhesive is organic silicon resin (KX605), and the addition amount of the adhesive is 1.8 wt% of the insulating soft magnetic material; the release agent is talcum powder, and the addition amount of the release agent is 0.3 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with the particle size of 100 meshes;

(1) the conductor 2 penetrates through the middle part of the modified magnetic powder and then is subjected to bidirectional pressing under 600 MPa; the conductor 2 is a cuboid copper sheet, and the length, the width and the height are 20 multiplied by 2.2 multiplied by 0.35 mm; the size of the magnet 1 obtained by punching is 13.5 × 4.9 × 3 mm;

(2) and (3) under the argon atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 700 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 35min to obtain the integrated co-fired inductor shown in the figure 1.

Example 8

The embodiment provides a preparation method of an integrated co-fired inductor, which comprises the following steps:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent is phosphoric acid; the addition amount of the passivating agent is 1 wt% of the soft magnetic material; the temperature of the passivation treatment is 120 ℃;

the soft magnetic material is gas atomized iron-silicon-chromium powder, gas atomized hydroxyl iron powder and gas atomized amorphous FeCuNbSiB powder. In the soft magnetic material, the superfine gas atomization hydroxyl iron powder accounts for 20 wt%, the fine powder gas atomization iron silicon chromium powder accounts for 20 wt%, the medium powder gas atomization amorphous FeCuNbSiB powder accounts for 30 wt%, and the coarse powder gas atomization amorphous FeCuNbSiB powder accounts for 30 wt%;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): (ii) mixing an insulating agent with the passivated soft magnetic material obtained in step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 0.4 wt% of the passivated soft magnetic material; the insulating agent is kaolin;

(iii) mixing a binder and a release agent with the insulated soft magnetic material obtained in the step (2); the adhesive is organic silicon resin (KX605), and the addition amount of the adhesive is 1.5 wt% of the insulating soft magnetic material; the release agent is calcium stearate, and the addition amount of the release agent is 0.3 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with the particle size of 100 meshes;

(1) the conductor 2 penetrates through the middle part of the modified magnetic powder and then is subjected to bidirectional pressing under 600 MPa; the conductor 2 is a cuboid copper sheet, and the length, the width and the height are 20 multiplied by 2.2 multiplied by 0.35 mm; the size of the magnet 1 obtained by punching is 13.5 × 4.9 × 3 mm;

(2) and (3) under a hydrogen atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 450 ℃ at a heating rate of 5 ℃/min, and preserving heat for 30min to obtain the integrated co-fired inductor shown in the figure 1.

Example 9

The embodiment provides a preparation method of an integrated co-fired inductor, which comprises the following steps:

preparing modified magnetic powder:

(i) passivating the soft magnetic material: mixing the soft magnetic material with a passivating agent to obtain a passivated soft magnetic material; the passivating agent is phosphoric acid; the addition amount of the passivating agent is 1 wt% of the soft magnetic material; the temperature of the passivation treatment is 120 ℃;

the soft magnetic material is gas atomized iron-silicon-chromium powder and gas atomized nanocrystalline FeSiB powder. In the soft magnetic material, the superfine gas atomized iron-silicon-chromium accounts for 37 wt%, the fine powder gas atomized nanocrystalline FeSiB powder accounts for 60 wt%, the medium powder gas atomized nanocrystalline FeSiB powder accounts for 3 wt%, and the coarse powder gas atomized amorphous FeCuNbSiB powder accounts for 30 wt%;

(ii) (ii) performing insulation treatment on the passivated soft magnetic material obtained in the step (i): (ii) mixing an insulating agent with the passivated soft magnetic material obtained in step (i) to obtain an insulating soft magnetic material; the addition amount of the insulating agent is 0.4 wt% of the passivated soft magnetic material; the insulating agent is silicon dioxide;

(iii) mixing a binder and a release agent with the insulated soft magnetic material obtained in the step (2); the adhesive is organic silicon resin (KX605), and the addition amount of the adhesive is 1.5 wt% of the insulating soft magnetic material; the release agent is calcium stearate, and the addition amount of the release agent is 0.3 wt% of the insulating soft magnetic material; granulating to obtain modified magnetic powder with the particle size of 100 meshes;

(1) the conductor 2 penetrates through the middle part of the modified magnetic powder and then is subjected to bidirectional pressing under 600 MPa; the conductor 2 is a cuboid copper sheet, and the length, the width and the height are 20 multiplied by 2.2 multiplied by 0.35 mm; the size of the magnet 1 obtained by punching is 13.5 × 4.9 × 3 mm;

(2) and (3) under a hydrogen atmosphere, heating the product obtained after the bidirectional pressing in the step (1) to 450 ℃ at a heating rate of 5 ℃/min, and preserving heat for 30min to obtain the integrated co-fired inductor shown in the figure 1.

Example 10

The embodiment provides a preparation method of an integrated co-fired inductor, which is the same as that in embodiment 1 except that copper sheets are replaced by aluminum sheets with the same size.

The inductance and efficiency of the integrated co-fired inductors provided in examples 1-10 were tested using a WK3260B inductance tester. During inductance testing, the testing frequency is 100kHz, the testing voltage is 1V, and direct current superposition is respectively 0A, 40A and 60A; the frequencies in the efficiency test are respectively 500kHz, 1MHz and 1MHz, and the corresponding loads are respectively 5A, 5A and 40A. The results obtained are shown in table 1.

TABLE 1

As can be seen from Table 1, the iron-nickel material has high initial inductance and good direct current superposition characteristics, can be used in combination with other powders, improves the inductance, and can be used under the conditions of high current and low frequency; the inductance value prepared by the iron-silicon-aluminum and iron-nickel composite powder is slightly low, and the fine powder and the ultrafine powder can improve the working frequency by selecting iron and nickel under the condition of ensuring the direct current superposition characteristic, which depends on low loss of the iron-silicon-aluminum and low eddy current loss of the ultrafine iron and nickel; the pressure is controlled below 800Mpa by bidirectional pressing, higher magnetic performance can be obtained, and the inductance efficiency is even better than that of the prior art; compared with a copper conductor, the resistivity of the conductor 2 seriously influences the efficiency of the inductor under the condition of large current; amorphous and nanocrystalline materials have low inductance but good high frequency characteristics and are suitable for use at high frequencies and high currents.

In conclusion, the modified magnetic powder with the conductor penetrating through the magnetic core is subjected to compression molding by adopting the low pressure of 300-1000MPa, so that the service life of the grinding tool is prolonged, the conductor can be effectively prevented from being broken, and the problem of short circuit between coils is effectively avoided. And the product after compression molding is subjected to heat treatment, so that the stress generated by compression molding can be effectively eliminated, the structure is more stable, and the magnetic conductivity and the Q value of the obtained integrated co-fired inductor are improved, thereby reducing the power consumption. Furthermore, because the conductor and the magnetic powder are integrally formed, the obtained integrated co-fired inductor has small volume and high space utilization rate, and is convenient for industrial application of the integrated co-fired inductor.

The applicant declares that the above description is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are within the scope and disclosure of the present invention.