阅读说明：本技术 一种耐热冲击NiZn铁氧体材料及其制备方法 (Heat-shock-resistant NiZn ferrite material and preparation method thereof ) 是由 朱晏军 聂敏 于 2020-04-01 设计创作，主要内容包括：一种NiZn铁氧体材料及其制备方法,该NiZn铁氧体材料包括：主成分,其包括：65.0wt％～68.0wt％的Fe<Sub>2</Sub>O<Sub>3</Sub>,11.0wt％～13.0wt％NiO,16.0wt％～20.0wt％ZnO,3.0wt％～6.0wt％CuO；添加剂包括玻璃粉,占总重量0.1wt％～1.0wt％；以占玻璃粉的重量百分比计,玻璃粉包括40.0wt％～70.0wt％的SiO<Sub>2</Sub>,2.0wt％～10.0wt％B<Sub>2</Sub>O<Sub>3</Sub>,1.0wt％～10.0wt％Na<Sub>2</Sub>O,1.0wt％～10.0wt％K<Sub>2</Sub>O,2.0wt％～6.0wt％Al<Sub>2</Sub>O<Sub>3</Sub>,1.0wt％～8.0wt％BaO,0.1wt％～1.0wt％Fe<Sub>2</Sub>O<Sub>3</Sub>,0.1wt％～1.0wt％NiO,0.1wt％～1.0wt％CuO,0.1wt％～1.0wt％ZnO。本发明能够有效提升NiZn铁氧体材料的耐热冲击能力,优于同类传统NiZn铁氧体材料,尤其适用于制作大尺寸超薄产品。(A NiZn ferrite material and a preparation method thereof, the NiZn ferrite material comprises: a principal component comprising: 65.0 wt% -68.0 wt% of Fe 2 O 3 11.0 wt% -13.0 wt% of NiO, 16.0 wt% -20.0 wt% of ZnO and 3.0 wt% -6.0 wt% of CuO; the additive comprises glass powder which accounts for 0.1-1.0 wt% of the total weight; the glass powder comprises 40.0-70.0 wt% of SiO in percentage by weight of the glass powder 2 ，2.0wt％～10.0wt％B 2 O 3 ，1.0wt％～10.0wt％Na 2 O，1.0wt％～10.0wt％K 2 O，2.0wt％～6.0wt％Al 2 O 3 ，1.0wt％～8.0wt％BaO，0.1wt％～1.0wt％Fe 2 O 3 0.1 wt% -1.0 wt% of NiO, 0.1 wt% -1.0 wt% of CuO and 0.1 wt% -1.0 wt% of ZnO. The invention can effectively improve the thermal shock resistance of the NiZn ferrite material, is superior to the similar traditional NiZn ferrite material, and is particularly suitable for manufacturing large-size ultrathin products.)

1. A NiZn ferrite material is characterized by comprising a main component and an additive;

the main component comprises the following components in percentage by weight:

the additive comprises the following components in percentage by weight of the NiZn ferrite material:

0.1 to 1.0 weight percent of glass powder

The glass powder comprises the following components in percentage by weight:

2. the NiZn ferrite material of claim 1, wherein Fe is in terms of purity₂O₃≥99.5wt％，NiO≥99.5wt％，ZnO≥99.5wt％，CuO≥99.5wt％，SiO₂≥99wt％，B₂O₃≥99wt％，Na₂O≥99wt％，K₂O≥99wt％，Al₂O₃≥99wt％，BaO≥99wt％。

3. A method of preparing a NiZn ferrite material, comprising: the NiZn ferrite material is prepared by preparing the ferrite main material and the glass frit separately according to the formulation of the main component and the additive of the NiZn ferrite material as set forth in claim 1 or 2, and preparing the NiZn ferrite material using the ferrite main material and the glass frit.

4. The method of claim 3, wherein preparing the glass frit comprises the steps of:

weighing the glass powder raw material SiO according to the formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to be 1400-1500 ℃, and preserving the heat for 2-4 hours; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

5. The method of claim 3 or 4, wherein preparing the ferrite master material comprises the steps of:

weighing main component raw material Fe according to a formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 1-5 mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 200-250 rpm, carrying out ball milling for 4-10 h, and controlling the particle size of powder to be 1.0 +/-0.2 mu m when D50 is equal to 1.0 mu m to prepare slurry; drying the obtained slurry in an oven, wherein the temperature of the oven is set to be 100-200 ℃ and the time is 10-24 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 830-880 ℃, setting the temperature rise curve to be 1-4 ℃/min, preserving the temperature for 2-4 h, and then naturally cooling to obtain the presintering powder.

6. The method of any one of claims 3 to 5, wherein preparing the NiZn ferrite material using the ferrite host material and the glass frit comprises the steps of:

weighing the prepared glass powder and ferrite pre-sintering powder according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 1-4 h, and the particle size of the powder is controlled to be D50 and is 1.0 mu m +/-0.2 mu m, so as to prepare slurry; drying the slurry obtained by ball milling according to the steps for later use;

adding a binder into the powder obtained in the last step, uniformly mixing, granulating, and pressing and molding the granulated powder; preferably, 10-20 wt% of a binder with a solid content of 10% is added into the powder obtained in the last step, the mixture is uniformly mixed and granulated, and the granulated powder is pressed into a ring shape, wherein the thickness is 3-4 mm, the inner diameter is 8.5-9 mm, the outer diameter is 13-15 mm, the forming pressure is 3-5T, and the pressure maintaining time is 2-5 s;

sintering the pressed material in a high-temperature sintering furnace to obtain the NiZn ferrite material; preferably, the sintering temperature is 1020 ℃ to 1150 ℃.

7. The method of claim 6, wherein the sintering comprises:

a temperature rising stage: slowly heating, slowly heating to 400-500 ℃ from room temperature at a heating rate of 0.3-1.0 ℃/min, and continuously heating to 800-900 ℃ at a heating rate of 1.0-2.0 ℃/min after the binder is discharged;

and (3) a blank gradual shrinkage stage: continuously heating to 1020-1150 ℃ at a heating rate of 0.5-1.5 ℃/min;

and (3) a heat preservation stage: preserving the heat for 1 to 4 hours at the temperature of between 1020 and 1150 ℃;

and (3) cooling: after the sintering, the temperature is reduced, and the cooling rate is 0.5 ℃/min to 2.0 ℃/min.

8. A method of making a magnetic core product of a NiZn ferrite material, comprising: the method for preparing a NiZn ferrite material according to any one of claims 3 to 7, wherein the glass powder and the ferrite pre-sintering powder are prepared, then the glass powder and the ferrite pre-sintering powder are mixed and ball-milled according to a ratio to form slurry, the slurry is dried to obtain powder, then the powder is used for compression molding of a magnetic core blank, and then the compressed magnetic core blank is sintered to obtain the NiZn ferrite material magnetic core product.

9. The method of claim 8, wherein the magnetic core is manufactured by dry molding by using powder obtained after drying, and performing spray granulation.

Technical Field

The invention relates to a ferrite material, in particular to a thermal shock resistant NiZn ferrite material and a preparation method thereof.

Background

The existing large-size nickel-zinc ferrite wound magnetic core product is not ideal in thermal shock resistance, the direct cracking after tin soldering is more than 3.0% (visual before polishing), the dark cracking phenomenon also exists after tin soldering is polished, and the cracking of the tin soldering after polishing is more than 20% (visual after polishing); it is urgently needed to develop a thermal shock resistant NiZn ferrite material with better performance for large-size ultrathin products, which is mainly suitable for large-size wound magnetic ferrite cores, and the thermal shock resistance of the material is expected to be substantially improved, the electromagnetic performance of the material is required to be ensured, and the yield and the performance of magnetic core products are improved.

Disclosure of Invention

In order to solve the technical problems, the invention provides a thermal shock resistant NiZn ferrite material and a preparation method thereof.

A NiZn ferrite material comprises a main component and an additive;

the main component comprises the following components in percentage by weight:

the additive comprises the following components in percentage by weight of the NiZn ferrite material:

0.1 to 1.0 weight percent of glass powder

The glass powder comprises the following components in percentage by weight:

further, in terms of purity, Fe₂O₃≥99.5wt％，NiO≥99.5wt％，ZnO≥99.5wt％，CuO≥99.5wt％，SiO₂≥99wt％，B₂O₃≥99wt％，Na₂O≥99wt％，K₂O≥99wt％，Al₂O₃≥99wt％，BaO≥99wt％。

A method of making a NiZn ferrite material, comprising: and respectively preparing the main ferrite material and the glass powder according to the formula of the main component and the additive of the NiZn ferrite material, and preparing the NiZn ferrite material by using the main ferrite material and the glass powder.

Further, the preparation of the glass powder comprises the following steps:

weighing the glass powder raw material SiO according to the formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to be 1400-1500 ℃, and preserving the heat for 2-4 hours; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

Further, the preparation of the ferrite main material comprises the following steps:

weighing main component raw material Fe according to a formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 1-5 mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 200-250 rpm, carrying out ball milling for 4-10 h, and controlling the particle size of powder to be 1.0 +/-0.2 mu m when D50 is equal to 1.0 mu m to prepare slurry; drying the obtained slurry in an oven, wherein the temperature of the oven is set to be 100-200 ℃ and the time is 10-24 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 830-880 ℃, setting the temperature rise curve to be 1-4 ℃/min, preserving the temperature for 2-4 h, and then naturally cooling to obtain the presintering powder.

Further, the preparation of the NiZn ferrite material using the ferrite main material and the glass frit comprises the steps of:

weighing the prepared glass powder and ferrite pre-sintering powder according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 1-4 h, and the particle size of the powder is controlled to be D50 and is 1.0 mu m +/-0.2 mu m, so as to prepare slurry; drying the slurry obtained by ball milling according to the steps for later use;

adding a binder into the powder obtained in the last step, uniformly mixing, granulating, and pressing and molding the granulated powder; preferably, 10-20 wt% of a binder with a solid content of 10% is added into the powder obtained in the last step, the mixture is uniformly mixed and granulated, and the granulated powder is pressed into a ring shape, wherein the thickness is 3-4 mm, the inner diameter is 8.5-9 mm, the outer diameter is 13-15 mm, the forming pressure is 3-5T, and the pressure maintaining time is 2-5 s;

sintering the pressed material in a high-temperature sintering furnace to obtain the NiZn ferrite material; preferably, the sintering temperature is 1020 ℃ to 1150 ℃.

Further, the sintering comprises:

a temperature rising stage: slowly heating, slowly heating to 400-500 ℃ from room temperature at a heating rate of 0.3-1.0 ℃/min, and continuously heating to 800-900 ℃ at a heating rate of 1.0-2.0 ℃/min after the binder is discharged;

and (3) a blank gradual shrinkage stage: continuously heating to 1020-1150 ℃ at a heating rate of 0.5-1.5 ℃/min;

and (3) a heat preservation stage: preserving the heat for 1 to 4 hours at the temperature of between 1020 and 1150 ℃;

and (3) cooling: after the sintering, the temperature is reduced, and the cooling rate is 0.5 ℃/min to 2.0 ℃/min.

A method of making a NiZn ferrite material core product, comprising: according to the method for preparing the NiZn ferrite material, the glass powder and the ferrite pre-sintering powder are firstly prepared, then the glass powder and the ferrite pre-sintering powder are mixed according to the proportion and are ball-milled to prepare slurry, the slurry is dried to obtain powder, then the powder is used for pressing and molding a magnetic core blank, and then the pressed magnetic core blank is sintered to obtain the NiZn ferrite material magnetic core product.

Further, the powder obtained after drying is used for spray granulation, and the magnetic core is manufactured by dry molding.

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

the NiZn ferrite material has compact microstructure, lower thermal expansion coefficient, contribution to improvement of mechanical impact performance and thermal shock resistance of the material, uniform crystallization of the material and obvious crystal boundary, the uniform crystallization can ensure that the heat conduction is faster, the thermal stress generated by thermal shock is relatively reduced, and the obvious crystal boundary can be used as a buffer zone for thermal shock crack expansion to inhibit the expansion of cracks, so that the thermal shock resistance of the material is effectively improved, the comprehensive performance is obviously superior to that of the similar traditional NiZn ferrite material, and the NiZn ferrite material is particularly suitable for manufacturing large-size ultrathin products.

Drawings

FIG. 1 is a flow chart of the preparation of NiZn ferrite material according to the embodiment of the present invention.

FIG. 2 is a microstructure view of a NiZn ferrite material according to an embodiment of the present invention.

Fig. 3 is a microstructure view of a conventional NiZn ferrite material.

Detailed Description

The invention will be further described with reference to the accompanying drawings and preferred embodiments.

The embodiment of the invention provides a NiZn ferrite material with thermal shock resistance, which comprises a main component and an additive;

the main component comprises the following components in percentage by weight:

the additive comprises the following components in percentage by weight of the NiZn ferrite material:

0.1 to 1.0 weight percent of glass powder

The glass powder comprises the following components in percentage by weight:

further, in terms of purity, Fe₂O₃≥99.5wt％，NiO≥99.5wt％，ZnO≥99.5wt％，CuO≥99.5wt％，SiO₂≥99wt％，B₂O₃≥99wt％，Na₂O≥99wt％，K₂O≥99wt％，Al₂O₃≥99wt％，BaO≥99wt％。

The embodiment of the invention also provides a manufacturing method of the NiZn ferrite material, which comprises the following steps:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1400-1500 ℃, and preserving the heat for 2-4 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 1 mm-5 mm and deionized water into a sand mill tank, setting the rotating speed of the sand mill to be 200-250 rpm, ball-milling for 4-10 h, controlling the particle size of powder to be 1.0 mu m +/-0.2 mu m after D50,preparing slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 100-200 ℃, and the time is 10-24 hours; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 830-880 ℃, setting the temperature rise curve to be 1-4 ℃/min, preserving the temperature for 2-4 h, and then naturally cooling to obtain the presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 1-4 h, and the particle size of the powder is controlled to be 1.0 micron +/-0.2 micron under D50, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

And 4, evaluating the performance of the NiZn thermal shock resistant material prepared in the step 3. And (3) adding 10-20 wt% of a binder with a solid content of 10% into the powder obtained in the step (4), uniformly mixing, granulating, pressing the granulated powder into a ring shape, wherein the thickness is 3-4 mm, the inner diameter is 8.5-9 mm, the outer diameter is 13-15 mm, the molding pressure is 3-5T, and the pressure maintaining time is 2-5 s.

And 5, sintering the annular ferrite material pressed in the step 4 in a high-temperature sintering furnace at the sintering temperature of 1020-1150 ℃, wherein the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating to 400-500 ℃ from room temperature at a heating rate of 0.3-1.0 ℃/min, and continuously heating to 800-900 ℃ at a heating rate of 1.0-2.0 ℃/min after the binder is discharged;

and (3) a blank gradual shrinkage stage: continuously heating to 1020-1150 ℃ at a heating rate of 0.5-1.5 ℃/min;

and (3) a heat preservation stage: preserving the heat for 1 to 4 hours at the temperature of between 1020 and 1150 ℃;

and (3) cooling: after the sintering, the temperature is reduced, and the cooling rate is 0.5 ℃/min to 2.0 ℃/min.

FIG. 1 is a flow chart of the preparation of a NiZn ferrite material according to an embodiment of the present invention.

In the aspect of raw material selection, the embodiment of the invention avoids the introduction of impurities as much as possible by adopting high-purity materials, thereby ensuring the quality of the raw materials. In the aspect of the formula, special purpose-made glass powder is adopted.

In the embodiment of the invention, in terms of grinding materials, zirconia balls and zirconia linings are preferably adopted for ball milling, so that metal Fe impurities are not easily mixed.

The embodiment of the invention also provides a preparation method of a magnetic core product (such as 4012 magnetic core), which comprises the following steps:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1400-1500 ℃, and preserving the heat for 2-4 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 1-5 mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 200-250 rpm, carrying out ball milling for 4-10 h, and controlling the particle size of powder to be 1.0 +/-0.2 mu m when D50 is equal to 1.0 mu m to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 100-200 ℃, and the time is 10-24 hours; then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 830-880 ℃, the temperature rise curve to be 1-4 ℃/min, and preserving the heat for 2-4 hAnd naturally cooling to obtain the pre-sintered powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 1-4 h, and the particle size of the powder is controlled to be 1.0 micron +/-0.2 micron under D50, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

Step 4, performing spray granulation on the powder obtained in the step 3, and manufacturing a magnetic core (such as 4012 magnetic core) by dry forming;

and 5, placing the magnetic core product manufactured in the step 4 into a high-temperature sintering furnace for sintering, wherein the sintering temperature is 1020-1150 ℃, and preferably, the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating to 400-500 ℃ from room temperature at a heating rate of 0.3-1.0 ℃/min, and continuously heating to 800-900 ℃ at a heating rate of 1.0-2.0 ℃/min after the binder is discharged;

and (3) a blank gradual shrinkage stage: continuously heating to 1020-1150 ℃ at a heating rate of 0.5-1.5 ℃/min;

and (3) a heat preservation stage: preserving the heat for 1 to 4 hours at the temperature of between 1020 and 1150 ℃;

and (3) cooling: after the sintering, the temperature is reduced, and the cooling rate is 0.5 ℃/min to 2.0 ℃/min.

Sintering directly determines the final composition of the ferrite material and the core, the distribution of the phases, grain size, compactness, size, appearance and properties. The sintering process includes determining proper sintering temperature and sintering curve based on the sintering apparatus, the pre-sintering temperature, the shrinkage of the pre-sintered material, the kind and adding proportion of the adhesive, the product performance requirement, shape, size, blank loading weight, mode, etc. the present inventors obtain the optimal scheme based on experiments to improve the performance of ferrite material and magnetic core product. The temperature rise stage mainly comprises the volatilization process of moisture and a binder in the blank, the temperature rise needs to be slowly carried out at the moment so as to avoid the blank from cracking, and then the blank gradually shrinks, and the temperature rise rate is proper at the moment because the sintering of the section influences the size, the uniformity, the porosity, the distribution and the like of the magnetic core grains; after reaching the highest sintering temperature, keeping the temperature for 1 to 4 hours; in the cooling stage, the cooling rate also has great influence on the electromagnetic performance and the qualification rate of the product.

Through the preferable sintering process, the product has no adhesion, deformation and cracking, and the consistency of the external dimension and the performance of the product meets the requirement.

The ferrite material sample prepared by the embodiment of the invention is tested, the inductance L and Q of a magnetic ring are tested by an E4991A +16454A radio frequency impedance analyzer, an oven and the like, and the magnetic permeability mui and the Curie temperature T of the material are calculated_c(ii) a A SY-8218 type hysteresis loop instrument is adopted to test the saturation magnetic induction intensity Bs of the material; testing the thermal expansion rate and the thermal expansion coefficient of the material by using a DIL4021PC/471 type thermal expansion instrument; and observing the microscopic morphology of the material by adopting a VEGA3EPH scanning electron microscope. And (3) evaluating the performance of the manufactured magnetic core, testing the core breaking strength and the swing breaking strength of the magnetic core by using a digital display push-pull dynamometer, and testing the thermal shock resistance of the magnetic core by using a soldering tin furnace.

In the frequency range of 10 KHz-1 MHz, the initial magnetic conductivity mui is 400 +/-25%; the saturation magnetic induction Bs (4000A/m) is 430 +/-5% mT; the Curie temperature Tc is more than or equal to 200 ℃.

Specific temperature coefficient α_{μir(20℃～60℃)}Is in the absolute value of (1 +/-0.5) × 10^-5Within.

Wherein, α_{μir(20℃～60℃)}＝[(μi_60℃-μi_20℃)/μi_20℃ ²]*[1/(T_60℃–T_20℃)]

μi_60℃: initial permeability at 60 ℃;

μi_20℃: initial permeability at 20 ℃.

The material has a coefficient of thermal expansion of 0.46% (400 ℃) and a coefficient of thermal expansion of 12.3 x 10^-6(400℃)。

And (3) testing conditions are as follows: RT-400 deg.C, 5 deg.C/min, no nitrogen.

Temperature/. degree.C.: 25 ℃/400 ℃.

Formula for calculating thermal expansion change rate of △ L/L₀％

Wherein:

△L/L₀％＝(L₁-L₀)/L₀％

L₀: length of 25 ℃ sample

L₁: length of sample at 400 ℃.

α formula for calculating coefficient of thermal expansion_T＝△L/(L₀*△T)％

Wherein:

△L/(L₀*△T)％＝(L1-L₀)/L₀*(T₁-T₀)％

L₀: length of 25 ℃ sample

L₁: length of 400 ℃ sample

T₁：400℃

T₀：25℃。

Through tests, the ferrite material provided by the embodiment of the invention has the initial permeability mu i of 400 +/-25%, the saturation magnetic induction Bs (4000A/m) of 430 +/-5% mT, the Curie temperature Tc of more than or equal to 200 ℃ and the specific temperature coefficient α at 20-60 ℃ in the frequency range of 10 KHz-1 MHz_μirHas an absolute value of (1 +/-0.5) × 10^-5(ii) a The material has a coefficient of thermal expansion of 0.46% (400 ℃) and a coefficient of thermal expansion of 12.3 x 10^-6(400 ℃ C.); the folding strength of a ripe blank core of a 4012 magnetic core pressed by the material is more than 80N, the folding strength of an electrode surface of the ripe blank is more than 8N, the testing is carried out at the soldering tin temperature of 370 ℃/3S, the magnetic core is not damaged before and after being polished visually, the testing is carried out at the soldering tin temperature of 390 ℃/0.9S, the magnetic core is not damaged before being polished visually, and the visual damage rate of the magnetic core after being polished is less than 5%. The material has compact microstructure and lower thermal expansion coefficient, is helpful for improving the mechanical impact performance and the thermal shock resistance of the material, has uniform crystallization and obvious crystal boundary, ensures that the heat conduction is quicker due to the uniform crystallization, relatively reduces the thermal stress generated by thermal shock, and can be used as a buffer zone for thermal shock crack expansion to inhibit the crack expansion, thereby improving the thermal shock resistance of the material and being superior to similar traditional materials in the industry.

The invention is further illustrated by the following more specific examples.

Example 1

A NiZn ferrite material with heat shock resistance comprises a main component and an additive component according to a formula;

the main components are as follows according to the weight of oxides:

the additive is specially-made glass powder, and accounts for the following main materials in weight:

0.5 percent of glass powder

The glass powder mainly contains SiO₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO, the components of which are calculated according to the total weight percentage of the glass powder,

the main components of the raw materials and the additive components are high-purity raw materials, and the purity is Fe₂O₃≥99.5wt％，NiO≥99.5wt％，ZnO≥99.5wt％，CuO≥99.5wt％，SiO₂≥99wt％，B₂O₃≥99wt％，Na₂O≥99wt％，K₂O≥99wt％，Al₂O₃≥99wt％，BaO≥99wt％。

A method for manufacturing a thermal shock resistant NiZn ferrite material for large-size ultrathin products comprises the following steps:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 830 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after heat preservation for 2 hours to obtain the presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

And 4, evaluating the performance of the NiZn thermal shock resistant material prepared in the step 3. Adding 15 wt% of a binder with a solid content of 10% into the powder obtained in the step 4, uniformly mixing, granulating, pressing the granulated powder into a ring shape, wherein the thickness is 3.3mm, the inner diameter is 9mm, the outer diameter is 14.7mm, the forming pressure is 3.5T, and the pressure maintaining time is 3 s.

And 5, sintering the annular ferrite material pressed in the step 4 in a high-temperature sintering furnace at 1050 ℃, wherein the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 830 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1050 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1050 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

Testing the prepared ferrite material sample, testing inductance L and Q of a magnetic ring by using an E4991A +16454A radio frequency impedance analyzer, an oven and the like, and calculating magnetic permeability mui and Curie temperature T of the material_c(ii) a A SY-8218 type hysteresis loop instrument is adopted to test the saturation magnetic induction intensity Bs of the material; testing the thermal expansion rate and the thermal expansion coefficient of the material by using a DIL4021PC/471 type thermal expansion instrument; the microscopic morphology of the material was observed by VEGA3EPH scanning electron microscope, and the test results are shown in Table 1.

A method of manufacturing a magnetic core product (e.g., 4012 core) using a thermal shock resistant NiZn ferrite material, comprising the steps of:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenchingVitrification, sanding the granular and blocky materials in a sand mill, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 830 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after heat preservation for 2 hours to obtain the presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

Step 4, performing spray granulation on the powder obtained in the step 3, and manufacturing a magnetic core (such as 4012 magnetic core) by dry forming;

and 5, placing the magnetic core product manufactured in the step 4 into a high-temperature sintering furnace for sintering, wherein the sintering temperature is 1050 ℃, and preferably, the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 830 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1050 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1050 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

And (3) evaluating the performance of the manufactured magnetic core, testing the core breaking strength and the swing breaking strength of the magnetic core by using a digital display push-pull dynamometer, and testing the thermal shock resistance of the magnetic core by using a soldering tin furnace, wherein the test results are shown in table 2.

The material has uniform crystallization and obvious crystal boundary, the heat conduction is faster due to the uniform crystallization, the thermal stress generated by thermal shock is relatively reduced, and the obvious crystal boundary can be used as a buffer zone for thermal shock crack expansion to inhibit the crack expansion, so that the thermal shock resistance of the material is improved.

Example 2

A NiZn ferrite material with heat shock resistance comprises a main component and an additive component according to a formula;

the main components are as follows according to the weight of oxides:

the additive is specially-made glass powder, and accounts for the following main materials in weight:

0.6 percent of glass powder

The glass powder mainly contains SiO₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO, the components of which are calculated according to the total weight percentage of the glass powder,

the main components of the raw materials and the additive components are high-purity raw materials, and the purity is Fe₂O₃≥99.5wt％，NiO≥99.5wt％，ZnO≥99.5wt％，CuO≥99.5wt％，SiO₂≥99wt％，B₂O₃≥99wt％，Na₂O≥99wt％，K₂O≥99wt％，Al₂O₃≥99wt％，BaO≥99wt％。

A method for manufacturing a thermal shock resistant NiZn ferrite material for large-size ultrathin products comprises the following steps:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 850 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after preserving the heat for 2 hours to obtain presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

And 4, evaluating the performance of the NiZn thermal shock resistant material prepared in the step 3. Adding 15 wt% of a binder with a solid content of 10% into the powder obtained in the step 4, uniformly mixing, granulating, pressing the granulated powder into a ring shape, wherein the thickness is 3.3mm, the inner diameter is 9mm, the outer diameter is 14.7mm, the forming pressure is 3.5T, and the pressure maintaining time is 3 s.

And 5, sintering the annular ferrite material pressed in the step 4 in a high-temperature sintering furnace at 1050 ℃, wherein the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 850 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1050 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1050 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

Testing the prepared ferrite material sample, testing inductance L and Q of a magnetic ring by using an E4991A +16454A radio frequency impedance analyzer, an oven and the like, and calculating magnetic permeability mui and Curie temperature T of the material_c(ii) a A SY-8218 type hysteresis loop instrument is adopted to test the saturation magnetic induction intensity Bs of the material; testing the thermal expansion rate and the thermal expansion coefficient of the material by using a DIL4021PC/471 type thermal expansion instrument; the microscopic morphology of the material was observed by VEGA3EPH scanning electron microscope, and the test results are shown in Table 1.

A method of manufacturing a magnetic core product (e.g., 4012 core) using a thermal shock resistant NiZn ferrite material, comprising the steps of:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; will weigh the good glassPutting the powder raw material into a roller ball mill, and mixing the following materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 850 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after preserving the heat for 2 hours to obtain presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

Step 4, performing spray granulation on the powder obtained in the step 3, and manufacturing a magnetic core (such as 4012 magnetic core) by dry forming;

and 5, placing the magnetic core product manufactured in the step 4 into a high-temperature sintering furnace for sintering, wherein the sintering temperature is 1050 ℃, and preferably, the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 850 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1050 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1050 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

And (3) evaluating the performance of the manufactured magnetic core, testing the core breaking strength and the swing breaking strength of the magnetic core by using a digital display push-pull dynamometer, and testing the thermal shock resistance of the magnetic core by using a soldering tin furnace, wherein the test results are shown in table 2.

Example 3

A NiZn ferrite material with heat shock resistance comprises a main component and an additive component according to a formula;

the main components are as follows according to the weight of oxides:

the additive is specially-made glass powder, and accounts for the following main materials in weight:

0.65 percent of glass powder

The glass powder mainly contains SiO₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO, the components of which are calculated according to the total weight percentage of the glass powder,

the main components of the raw materials and the additive components are high-purity raw materials, and the purity is Fe₂O₃≥99.5wt％，NiO≥99.5wt％，ZnO≥99.5wt％，CuO≥99.5wt％，SiO₂≥99wt％，B₂O₃≥99wt％，Na₂O≥99wt％，K₂O≥99wt％，Al₂O₃≥99wt％，BaO≥99wt％。

A method for manufacturing a thermal shock resistant NiZn ferrite material for large-size ultrathin products comprises the following steps:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 860 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after heat preservation for 2 hours to obtain presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

And 4, evaluating the performance of the NiZn thermal shock resistant material prepared in the step 3. Adding 15 wt% of a binder with a solid content of 10% into the powder obtained in the step 4, uniformly mixing, granulating, pressing the granulated powder into a ring shape, wherein the thickness is 3.3mm, the inner diameter is 9mm, the outer diameter is 14.7mm, the forming pressure is 3.5T, and the pressure maintaining time is 3 s.

And 5, placing the annular ferrite material pressed in the step 4 into a high-temperature sintering furnace for sintering, wherein the sintering temperature is 1060 ℃, and the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 860 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1060 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1060 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

Testing the prepared ferrite material sample, testing inductance L and Q of a magnetic ring by using an E4991A +16454A radio frequency impedance analyzer, an oven and the like, and calculating magnetic permeability mui and Curie temperature T of the material_c(ii) a A SY-8218 type hysteresis loop instrument is adopted to test the saturation magnetic induction intensity Bs of the material; testing the thermal expansion rate and the thermal expansion coefficient of the material by using a DIL4021PC/471 type thermal expansion instrument; the microscopic morphology of the material was observed by VEGA3EPH scanning electron microscope, and the test results are shown in Table 1.

A method of manufacturing a magnetic core product (e.g., 4012 core) using a thermal shock resistant NiZn ferrite material, comprising the steps of:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 860 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after heat preservation for 2 hours to obtain presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

Step 4, performing spray granulation on the powder obtained in the step 3, and manufacturing a magnetic core (such as 4012 magnetic core) by dry forming;

and 5, placing the magnetic core product manufactured in the step 4 into a high-temperature sintering furnace for sintering, wherein the sintering temperature is 1060 ℃, and preferably, the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 860 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1060 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1060 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

And (3) evaluating the performance of the manufactured magnetic core, testing the core breaking strength and the swing breaking strength of the magnetic core by using a digital display push-pull dynamometer, and testing the thermal shock resistance of the magnetic core by using a soldering tin furnace, wherein the test results are shown in table 2.

Example 4

A NiZn ferrite material with heat shock resistance comprises a main component and an additive component according to a formula;

the main components are as follows according to the weight of oxides:

the additive is specially-made glass powder, and accounts for the following main materials in weight:

0.7 percent of glass powder

The glass powder mainly contains SiO₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO, the components of which are calculated according to the total weight percentage of the glass powder,

the main components of the raw materials and the additive components are high-purity raw materials, and the purity is Fe₂O₃≥99.5wt％，NiO≥99.5wt％，ZnO≥99.5wt％，CuO≥99.5wt％，SiO₂≥99wt％，B₂O₃≥99wt％，Na₂O≥99wt％，K₂O≥99wt％，Al₂O₃≥99wt％，BaO≥99wt％。

A method for manufacturing a thermal shock resistant NiZn ferrite material for large-size ultrathin products comprises the following steps:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 860 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after heat preservation for 2 hours to obtain presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

And 4, evaluating the performance of the NiZn thermal shock resistant material prepared in the step 3. Adding 15 wt% of a binder with a solid content of 10% into the powder obtained in the step 4, uniformly mixing, granulating, pressing the granulated powder into a ring shape, wherein the thickness is 3.3mm, the inner diameter is 9mm, the outer diameter is 14.7mm, the forming pressure is 3.5T, and the pressure maintaining time is 3 s.

And 5, sintering the annular ferrite material pressed in the step 4 in a high-temperature sintering furnace at 1070 ℃, wherein the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 860 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1070 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1070 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

Testing the prepared ferrite material sample, testing inductance L and Q of a magnetic ring by using an E4991A +16454A radio frequency impedance analyzer, an oven and the like, and calculating magnetic permeability mui and Curie temperature T of the material_c(ii) a A SY-8218 type hysteresis loop instrument is adopted to test the saturation magnetic induction intensity Bs of the material; testing the thermal expansion rate and the thermal expansion coefficient of the material by using a DIL4021PC/471 type thermal expansion instrument; the microscopic morphology of the material was observed by VEGA3EPH scanning electron microscope, and the test results are shown in Table 1.

A method of manufacturing a magnetic core product (e.g., 4012 core) using a thermal shock resistant NiZn ferrite material, comprising the steps of:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 860 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after heat preservation for 2 hours to obtain presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

Step 4, performing spray granulation on the powder obtained in the step 3, and manufacturing a magnetic core (such as 4012 magnetic core) by dry forming;

and 5, placing the magnetic core product manufactured in the step 4 into a high-temperature sintering furnace for sintering, wherein the sintering temperature is 1070 ℃, and preferably, the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 860 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1070 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1070 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

And (3) evaluating the performance of the manufactured magnetic core, testing the core breaking strength and the swing breaking strength of the magnetic core by using a digital display push-pull dynamometer, and testing the thermal shock resistance of the magnetic core by using a soldering tin furnace, wherein the test results are shown in table 2.

Example 5

A NiZn ferrite material with heat shock resistance comprises a main component and an additive component according to a formula;

the main components are as follows according to the weight of oxides:

the additive is specially-made glass powder, and accounts for the following main materials in weight:

0.7 percent of glass powder

The glass powder mainly contains SiO₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO, the components of which are calculated according to the total weight percentage of the glass powder,

the main components of the raw materials and the additive components are high-purity raw materials, and the purity is Fe₂O₃≥99.5wt％，NiO≥99.5wt％，ZnO≥99.5wt％，CuO≥99.5wt％，SiO₂≥99wt％，B₂O₃≥99wt％，Na₂O≥99wt％，K₂O≥99wt％，Al₂O₃≥99wt％，BaO≥99wt％。

A method for manufacturing a thermal shock resistant NiZn ferrite material for large-size ultrathin products comprises the following steps:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 850 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after preserving the heat for 2 hours to obtain presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

And 4, evaluating the performance of the NiZn thermal shock resistant material prepared in the step 3. Adding 15 wt% of a binder with a solid content of 10% into the powder obtained in the step 4, uniformly mixing, granulating, pressing the granulated powder into a ring shape, wherein the thickness is 3.3mm, the inner diameter is 9mm, the outer diameter is 14.7mm, the forming pressure is 3.5T, and the pressure maintaining time is 3 s.

And 5, sintering the annular ferrite material pressed in the step 4 in a high-temperature sintering furnace at 1080 ℃, wherein the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 850 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1080 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1080 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

Testing the prepared ferrite material sample, testing inductance L and Q of a magnetic ring by using an E4991A +16454A radio frequency impedance analyzer, an oven and the like, and calculating magnetic permeability mui and Curie temperature T of the material_c(ii) a A SY-8218 type hysteresis loop instrument is adopted to test the saturation magnetic induction intensity Bs of the material; testing the thermal expansion rate and the thermal expansion coefficient of the material by using a DIL4021PC/471 type thermal expansion instrument; the microscopic morphology of the material was observed by VEGA3EPH scanning electron microscope, and the test results are shown in Table 1.

A method of manufacturing a magnetic core product (e.g., 4012 core) using a thermal shock resistant NiZn ferrite material, comprising the steps of:

step 1, manufacturing special glass powder.

The special glass powder is prepared by a general method, namely a melting-quenching-crushing method. Firstly, weighing raw material SiO required for preparing glass powder according to a formula₂、B₂O₃、Na₂O、K₂O、Al₂O₃、BaO、Fe₂O₃NiO, CuO and ZnO for standby; putting the weighed glass powder raw materials into a roller ball mill, and mixing the raw materials: the ball mass ratio is 1: 4, performing mixed ball milling, pouring the mixture into a crucible after ball milling for 4 hours, putting the crucible into a melting furnace, setting the melting temperature to 1450 ℃, and preserving heat for 3 hours, so that the mixture becomes completely uniform and clear; then pouring the molten liquid into a water tank for quenching to vitrify, then putting the granules and the blocks into a sand mill for sand milling, controlling the granularity of D50 to be 1.0 mu m +/-0.5 mu m, and drying for later use.

And 2, preparing a ferrite main material.

Raw material Fe is weighed according to the formula₂O₃NiO, ZnO and CuO for standby; putting the weighed main component raw materials into a sand mill, and mixing the raw materials in parts by weight: ball: the water mass ratio is 1: 4: 1.5, adding zirconia balls with the diameter of 4mm and deionized water into a sand mill tank, setting the rotation speed of the sand mill to be 250rpm, and after ball milling for 4 hours, controlling the particle size of powder to be 1.0 micron +/-0.2 micron when D50 is equal to 1.0 micron to prepare slurry; drying the slurry obtained in the step (2) in an oven, wherein the temperature of the oven is set to be 150 ℃, and the time is 15 h; and then placing the powder in a high-temperature sintering furnace for presintering, setting the temperature to be 850 ℃, setting the temperature rise curve to be 1.5 ℃/min, and naturally cooling after preserving the heat for 2 hours to obtain presintering powder.

And 3, preparing the NiZn thermal shock resistant material for the large-size ultrathin product.

Weighing the glass powder prepared in the step 1 and the ferrite pre-sintering powder prepared in the step 2 according to a formula, placing the powder into a ball mill tank for ball milling, wherein the ball milling time is 4 hours, and the particle size of the powder is controlled to be D50 within 1.0 mu m +/-0.2 mu m, so as to prepare slurry; and drying the slurry obtained by ball milling according to the steps for later use.

Step 4, performing spray granulation on the powder obtained in the step 3, and manufacturing a magnetic core (such as 4012 magnetic core) by dry forming;

and 5, placing the magnetic core product manufactured in the step 4 into a high-temperature sintering furnace for sintering, wherein the sintering temperature is 1080 ℃, and preferably, the sintering comprises the following steps:

a temperature rising stage: slowly heating, slowly heating from room temperature to 450 ℃ at a heating rate of 0.8 ℃/min, keeping the temperature for 2h, continuously heating to 850 ℃ at a heating rate of 1.5 ℃/min after the binder is discharged, and keeping the temperature for 2 h;

and (3) a blank gradual shrinkage stage: continuously heating to 1080 ℃ at the heating rate of 1.5 ℃/min;

and (3) a heat preservation stage: keeping the temperature at 1080 ℃ for 2 h;

and (3) cooling: after firing, the temperature is reduced, and the cooling rate is 1.5 ℃/min.

And (3) evaluating the performance of the manufactured magnetic core, testing the core breaking strength and the swing breaking strength of the magnetic core by using a digital display push-pull dynamometer, and testing the thermal shock resistance of the magnetic core by using a soldering tin furnace, wherein the test results are shown in table 2.

The NiZn thermal shock resistant materials produced in the five examples above were tested for properties, as compared to the properties associated with conventional materials, as shown in table 1, table 2, fig. 2 and fig. 3:

table 1 comparison of material test results

TABLE 24012 comparison of product test results

The results of the tests of the examples 1 to 5 show that the electromagnetic properties of the NiZn thermal shock resistant material are superior to those of the traditional material.

Material properties as in example 4 of the invention:

in the frequency range of 10 KHz-1 MHz, the initial magnetic permeability mui is 413, the saturation magnetic induction Bs (4000A/m) is 435mT, the Curie temperature Tc is 250 ℃, and the specific temperature coefficient α at 20-60 DEG C_μirIs 1.4 x 10^-5(ii) a MaterialHas a coefficient of thermal expansion of 0.46% (400 ℃), and a coefficient of thermal expansion of 12.3 x 10^-6(400 ℃ C.). The folding strength of a ripe blank core of a 4012 magnetic core pressed by the material is more than 80N, the folding strength of an electrode surface of the ripe blank is more than 8N, the testing is carried out at the soldering tin temperature of 370 ℃/3S, the magnetic core is not damaged before and after being polished visually, the testing is carried out at the soldering tin temperature of 390 ℃/0.9S, the magnetic core is not damaged before being polished visually, and the visual damage rate of the magnetic core after being polished is less than 5%.

Material properties of conventional materials:

in the frequency range of 10 KHz-1 MHz, the initial magnetic permeability mui is 390, the saturation magnetic induction Bs (4000A/m) is 420mT, the Curie temperature Tc is 220 ℃, and the specific temperature coefficient α at 20-60 DEG C_μirHas an absolute value of 2.1 x 10^-5(ii) a The material has a coefficient of thermal expansion of 0.51% (400 ℃) and a coefficient of thermal expansion of 14.3 x 10^-6(400 ℃ C.); the breaking strength of a wrought core blank of a 4012 magnetic core pressed by the material is 74N, the bending strength of an electrode surface of the wrought core blank is 6N, the test is carried out at the soldering tin temperature of 370 ℃/3S, the magnetic core is visually undamaged before and after being polished, the test is carried out at the soldering tin temperature of 390 ℃/0.9S, the visual damage rate of the magnetic core before being polished is more than 5%, and the visual damage rate of the magnetic core after being polished is more than 20%.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several equivalent substitutions or obvious modifications can be made without departing from the spirit of the invention, and all the properties or uses are considered to be within the scope of the invention.