Power ferrite material, method for preparing the same and automobile electronic product

Abstract

The application provides a power ferrite material, a preparation method thereof and an automobile electronic product, and the power ferrite material is composed of a base material and an additive; the base material comprises, in terms of mole percentage, Fe2O3 52.95-53.25 mol%; MnO 36.55-37.05 mol%; and ZnO 9.7-10.5 mol%; and the additive comprises, in terms of total mass of the base material being 100%, CaCO3 0.13-0.18%; and Co2O3 0.2-0.33%. The composition of the power ferrite material is regulated, so that the alternating current resistance (ACR) value of the power ferrite material under the condition of 25 DEG C, 200 kHz and 0.5 V is reduced, and thus the UF40 product is facilitated to be applied in the automobile field.

Description

Technical Field

[0001] This invention belongs to the field of ferrite material technology, specifically relating to a power ferrite material, its preparation method, and automotive electronic products. Background Technology

[0002] In recent years, with the rapid development of the electronics and information industry, the demand for manganese-zinc ferrites has shown a steady upward trend. Especially in emerging fields such as new energy vehicles, 5G communications, and industrial automation, the application prospects of manganese-zinc ferrites are even broader. These fields have increasingly higher performance requirements for electronic components, and manganese-zinc ferrites, with their excellent magnetic properties, can meet these high demands.

[0003] Existing manganese-zinc ferrites are mainly divided into two categories: power manganese-zinc ferrites and high-conductivity manganese-zinc ferrites. Power manganese-zinc ferrite materials are mainly used in electronic transformers of various switching power supplies to achieve functions such as voltage transformation, current transformation, and impedance transformation. Switching power supply transformers need to maintain good electromagnetic performance at high frequencies and large currents, thus requiring characteristics such as low power loss, high saturation magnetic induction intensity, and wide temperature range. High-conductivity manganese-zinc ferrite materials are mainly used in broadband transformers and pulse transformers in fields such as digital networks and communication systems. Electronic transformers in these fields have high requirements for material volume and permeability, thus requiring characteristics such as wide-bandwidth high permeability, high Curie temperature, and high impedance.

[0004] For example, CN116283263A discloses that the power loss of ferrite materials is 268 kW / m under the conditions of 100℃, 100 kHz and 200 mT. 3 CN114685154A discloses a high-frequency, wide-temperature, ultra-low-loss ferrite material with power loss of 240-265 kW / m under conditions of 100℃, 200 kHz, and 125 mT. 3 .

[0005] However, in the automotive field, some special application environments require a reduction in the AC resistance (ACR) value of products (such as UF40), but none of the above-mentioned technical solutions disclosed in the prior art involve how to reduce the ACR value of manganese zinc ferrite materials.

[0006] Therefore, there is an urgent need in this field to develop a product and its preparation method for reducing the ACR value of manganese-zinc ferrite materials. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a power ferrite material, its preparation method, and automotive electronic products. This invention reduces the AC resistance (ACR) of the power ferrite material at 25°C, 200kHz, and 0.5V by controlling its composition, thereby facilitating the application of UF40 products in the automotive field.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a power ferrite material, which is composed of a matrix material and additives:

[0010] The matrix material comprises, in mole percentage:

[0011] Fe2O3 52.95-53.25 mol%.

[0012] MnO 36.55-37.05 mol%;

[0013] ZnO 9.7-10.5 mol%;

[0014] Based on the total mass of the matrix material as 100%, the additives include:

[0015] CaCO3 0.13-0.18%;

[0016] Co2O3 0.2-0.33%.

[0017] This invention adjusts the content ratio of each component in the matrix material and additives to shift the valley point towards negative temperature. As a result, the power ferrite material not only possesses high saturation magnetic induction (Bs), high magnetic permeability, and low loss performance, but also further reduces its AC resistance (ACR) value under conditions of 25°C, 200kHz, and 0.5V. This allows the UF40 product to better adapt to various special environments in the automotive field, thereby improving its application effect and reliability in automotive electronic devices.

[0018] The principle of this invention is as follows: This invention discovers that reducing the AC resistance (ACR) of a material or the AC resistance (ACR) value of a product can be achieved by reducing the inductance (L) of the material. The specific principle is based on the following formula: ACR = 2πfL / Q, where f is the frequency in Hz; L is the inductance in H; and Q is the quality factor.

[0019] In terms of reducing the inductance of materials, this invention uses the method of moving the valley point of the material outside the required temperature point. For example, this invention requires reducing the AC resistance (ACR) value of the UF40 product under the conditions of 25°C, 200kHz and 0.5V. This invention moves the valley point to less than 25°C, for example, adjusts it to 10°C, thus reducing the inductance of the material at 25°C.

[0020] Furthermore, this invention also discovered that by increasing the iron content, the material's valley point can be shifted towards negative temperatures, but this requires the addition of a Co2O3 component to achieve the aforementioned effect. In summary, on the one hand, this invention reduces the material's resistivity; on the other hand, by shifting the material's valley point to a suitable range, it ultimately reduces the material's inductance at 25°C. Thus, the AC resistance (ACR) of the UF40 product is correspondingly reduced at 25°C, 200kHz, and 0.5V. Moreover, the material's inductance is closely related to its physical properties, such as the thickness of grain boundaries, which can affect the material's electron transport characteristics and magnetic properties. If the amount of CaCO3 component precipitated at the grain boundaries is too small, leading to an increase in the material's inductance, the AC resistance will also increase accordingly.

[0021] In this invention, the molar percentage of Fe2O3 is 52.95-53.25 mol%, for example, it can be 52.95 mol%, 53.0 mol%, 53.05 mol%, 53.08 mol%, 53.1 mol%, 53.15 mol%, 53.18 mol%, 53.2 mol%, 53.25 mol%, etc.

[0022] In this invention, the molar percentage of MnO is 36.55-37.05 mol%, for example, it can be 36.55 mol%, 36.58 mol%, 36.6 mol%, 36.65 mol%, 36.7 mol%, 36.8 mol%, 36.9 mol%, 37.0 mol%, 37.05 mol%, etc.

[0023] In this invention, the molar percentage of ZnO is 9.7-10.5 mol%, for example, it can be 9.7 mol%, 9.8 mol%, 9.9 mol%, 10.0 mol%, 10.2 mol%, 10.5 mol%, etc.

[0024] In this invention, the mass percentage of CaCO3 is 0.13-0.18% based on the total mass of the matrix material as 100%, for example, it can be 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, etc.

[0025] In this invention, based on the total mass of the matrix material as 100%, the mass percentage of Co2O3 is 0.2-0.33%, for example, it can be 0.2%, 0.22%, 0.25%, 0.28%, 0.3%, 0.33%, etc.

[0026] In this invention, the proportions of the matrix material components need to be controlled within the aforementioned range. If the iron content is too high, the material's valley point will shift to a sub-zero temperature, resulting in a smaller Q value and ultimately an increase in the material's AC resistance. If the iron content is too low, the material's ACR will also be too high, due to the material's higher inductance.

[0027] Furthermore, by adjusting the MnO content range, this invention ensures that the material's valley point is within a suitable range. If the MnO content is too low, the material's valley point will shift towards 25°C, resulting in increased inductance and a corresponding increase in ACR.

[0028] In this invention, the content of Co2O3 additive is controlled to give the material a lower AC resistance. If the amount of Co2O3 added is too high, the Q value of the material will decrease, and the AC resistance will increase accordingly; if the amount of Co2O3 added is too low, the Q value will also decrease, and the AC resistance will increase accordingly.

[0029] Preferably, the valley point of the power ferrite material is 15°C.

[0030] Preferably, the power ferrite material has an AC resistance of less than 235mΩ under the conditions of 25°C, 200kHz and 0.5V.

[0031] This invention reduces the AC resistance of power ferrite materials at 25°C, 200kHz, and 0.5V by adjusting the valley point of the power ferrite material.

[0032] In a second aspect, the present invention provides a method for preparing the power ferrite material according to the first aspect, the method comprising the following steps:

[0033] (1) The matrix material is subjected to first sand milling, first spray granulation and pre-calcination treatment in sequence according to the formula to obtain pre-calcined material;

[0034] (2) The additives and the pre-burned material obtained in step (1) are subjected to a second sand milling treatment, a second spray granulation treatment, a pressing and molding treatment and a sintering treatment in accordance with the formula amount to obtain the power ferrite material.

[0035] Preferably, the mass ratio of the first powder, the first grinding ball and the first grinding aid in the first grinding process in step (1) is 1:(6-8):(0.6-0.7), for example, it can be 1:6:0.6, 1:6.5:0.65, 1:7:0.65, 1:7.5:0.6, 1:8:0.7, etc.

[0036] Preferably, the first grinding aid comprises water.

[0037] Preferably, the time for the first sand milling process in step (1) is 60-70 minutes, for example, 60 minutes, 62 minutes, 65 minutes, 68 minutes, 70 minutes, etc.

[0038] Preferably, the average particle size of the powder after the first sand milling process in step (1) is 0.65μm-0.9μm, for example, it can be 0.66μm, 0.68μm, 0.72μm, 0.78μm, 0.81μm, 0.85μm, 0.9μm, etc.

[0039] Preferably, the mass concentration of the first adhesive used in the first spray granulation process in step (1) is 5%-15%, for example, it can be 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 11%, 12%, 13%, 14%, 15%, etc.

[0040] Preferably, the first adhesive has a mass percentage of 10%, based on the total mass of the pre-fired material in step (1) being 100%.

[0041] Preferably, the temperature of the pre-firing treatment in step (1) is 850°C and the time is 1-5 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, etc.

[0042] Preferably, the mass ratio of the second powder, the second grinding ball and the second grinding aid in the second grinding process in step (2) is 1:(6-8):(0.6-0.7), for example, it can be 1:6:0.6, 1:6.5:0.65, 1:7:0.65, 1:7.5:0.6, 1:8:0.7, etc.

[0043] Preferably, the second grinding aid comprises water.

[0044] Preferably, the time for the second sand milling process in step (2) is 150-240 min, for example, 150 min, 165 min, 185 min, 200 min, 220 min, 240 min, etc.

[0045] Preferably, the average particle size of the powder after the second sand milling process in step (2) is 0.95μm-1.15μm, for example, it can be 0.98μm, 1.01μm, 1.05μm, 1.1μm, 1.12μm, 1.15μm, etc.

[0046] Preferably, the mass concentration of the second adhesive used in the second spray granulation process in step (2) is 5%-15%, for example, it can be 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 11%, 12%, 13%, 14%, 15%, etc.

[0047] Preferably, the mass percentage of the second adhesive is 10%, based on the total mass of the powder in the second sand milling process described in step (2) being 100%.

[0048] Preferably, the sintering temperature in step (2) is 1260℃-1300℃, for example, 1260℃, 1270℃, 1280℃, 1290℃, 1300℃, etc.; and the time is 5-7h, for example, 5h, 6h, 7h, etc.

[0049] Thirdly, the present invention provides an automotive electronic product comprising the power ferrite material according to the first aspect.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] This invention provides a power ferrite material. By adjusting the content ratio of each component in the matrix material and additives, the valley point is shifted towards the negative temperature direction. As a result, the power ferrite material not only has high saturation magnetic induction intensity (Bs), high magnetic permeability, and low loss performance, but also further reduces its AC resistance (ACR) value under the conditions of 25°C, 200kHz, and 0.5V. This allows UF40 products to better adapt to various special environments in the automotive field, thereby improving their application effect and reliability in automotive electronic devices.

[0052] The principle of this invention is as follows: This invention discovers that reducing the AC resistance (ACR) of a material or the AC resistance (ACR) value of a product can be achieved by reducing the inductance (L) of the material. The specific principle is based on the following formula: ACR = 2πfL / Q, where f is the frequency in Hz; L is the inductance in H; and Q is the quality factor.

[0053] In terms of reducing the inductance of materials, this invention uses the method of moving the valley point of the material outside the required temperature point. For example, this invention requires reducing the AC resistance (ACR) value of the UF40 product under the conditions of 25°C, 200kHz and 0.5V. This invention moves the valley point to less than 25°C, for example, adjusts it to 10°C, thus reducing the inductance of the material at 25°C.

[0054] Furthermore, this invention also discovered that by increasing the iron content, the material's valley point can be shifted towards negative temperatures, but this requires the addition of a Co2O3 component to achieve the aforementioned effect. In summary, on the one hand, this invention reduces the material's resistivity; on the other hand, by shifting the material's valley point to a suitable range, it ultimately reduces the material's inductance at 25°C. Thus, the AC resistance (ACR) of the UF40 product is correspondingly reduced at 25°C, 200kHz, and 0.5V. Moreover, the material's inductance is closely related to its physical properties, such as the thickness of grain boundaries, which can affect the material's electron transport characteristics and magnetic properties. If the amount of CaCO3 component precipitated at the grain boundaries is too small, leading to an increase in the material's inductance, the AC resistance will also increase accordingly. Detailed Implementation

[0055] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0056] Unless otherwise specified, the raw materials and equipment used in this invention can be purchased from the market or are commonly used in the field.

[0057] Example 1

[0058] This embodiment provides a power ferrite material with a valley point of 15°C. The AC resistance of the power ferrite material is less than 235mΩ under the conditions of 25°C, 200kHz, and 0.5V. The power ferrite material is composed of a matrix material and additives.

[0059] The matrix material comprises, by mole percentage: 52.95 mol% Fe2O3, 36.55 mol% MnO and 10.5 mol% ZnO; the additives comprise, by total mass of the matrix material: 0.13% CaCO3 and 0.3% Co2O3.

[0060] This embodiment also provides a method for preparing the above-mentioned power ferrite material, which includes the following steps:

[0061] (1) The matrix material was subjected to a first sand milling treatment according to the formula. The powder, sand milling balls and water were subjected to a first sand milling treatment for 70 min in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.75 μm. Based on the total mass of the pre-fired material as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) was added and subjected to a first spray granulation treatment and a pre-fired treatment at 850℃ in a rotary kiln for 3 h to obtain the pre-fired material.

[0062] (2) The additives and the pre-calcined material obtained in step (1) are subjected to a second sand milling treatment according to the formula amount. The powder, sand milling ball and water are subjected to a second sand milling treatment for 200 min in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.98 μm. Taking the total mass of the powder in the second sand milling treatment as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) is added and subjected to a second spray granulation treatment, compression molding treatment and sintering treatment at 1280℃ for 6 h in sequence to obtain the power ferrite material.

[0063] Comparative Example 1

[0064] This comparative example provides a power ferrite material, which is composed of a matrix material and additives:

[0065] The matrix material comprises, by mole percentage: 52.3 mol% Fe2O3, 37.2 mol% MnO and 10.5 mol% ZnO; the additives comprise, by total mass of the matrix material: 0.13% CaCO3 and 0.3% Co2O3.

[0066] This comparative example also provides a method for preparing the above-mentioned power ferrite material, which includes the following steps:

[0067] (1) The matrix material was subjected to a first sand milling treatment according to the formula. The powder, sand milling balls and water were milled for 70 minutes in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.78 μm. Based on the total mass of the pre-fired material as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) was added and the material was subjected to a first spray granulation treatment and a pre-fired treatment at 850°C in a rotary kiln for 3 hours to obtain the pre-fired material.

[0068] (2) The additives and the pre-calcined material obtained in step (1) are subjected to a second sand milling treatment according to the formula amount. The powder, sand milling ball and water are subjected to a second sand milling treatment for 200 min in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.99 μm. Taking the total mass of the powder in the second sand milling treatment as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) is added and subjected to a second spray granulation treatment, compression molding treatment and sintering treatment at 1280℃ for 6 h in sequence to obtain the power ferrite material.

[0069] The AC resistance of the power ferrite materials obtained in Example 1 and Comparative Example 1 was measured, and the results are shown in Table 1:

[0070] Table 1

[0071]

[0072] As shown in Table 1, the low iron content leads to a higher AC resistance of the power ferrite material at 25℃, 200kHz and 0.5V.

[0073] Example 2

[0074] This embodiment provides a power ferrite material with a valley point of 15°C. The AC resistance of the power ferrite material is less than 235mΩ under the conditions of 25°C, 200kHz, and 0.5V. The power ferrite material is composed of a matrix material and additives.

[0075] The matrix material comprises, by mole percentage: 53.25 mol% Fe2O3, 37.05 mol% MnO and 9.7 mol% ZnO; the additives comprise, by total mass of the matrix material: 0.18% CaCO3 and 0.25% Co2O3.

[0076] This embodiment also provides a method for preparing the above-mentioned power ferrite material, which includes the following steps:

[0077] (1) The matrix material was subjected to a first sand milling treatment according to the formula. The powder, sand milling balls and water were subjected to a first sand milling treatment for 60 min in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.82 μm. Based on the total mass of the pre-fired material as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) was added and subjected to a first spray granulation treatment and a pre-fired treatment at 850℃ in a rotary kiln for 4 h to obtain the pre-fired material.

[0078] (2) The additives and the pre-calcined material obtained in step (1) are subjected to a second sand milling treatment according to the formula amount. The powder, sand milling ball and water are subjected to a second sand milling treatment for 190 min in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.99 μm. Taking the total mass of the powder in the second sand milling treatment as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) is added and subjected to a second spray granulation treatment, compression molding treatment and sintering treatment at 1290℃ for 7 h in sequence to obtain the power ferrite material.

[0079] Comparative Example 2

[0080] This comparative example provides a power ferrite material, which is composed of a matrix material and additives:

[0081] The matrix material comprises, by mole percentage: 53.25 mol% Fe2O3, 37.05 mol% MnO and 9.7 mol% ZnO; the additives comprise, by total mass of the matrix material: 0.18% CaCO3 and 0.45% Co2O3.

[0082] This comparative example also provides a method for preparing the above-mentioned power ferrite material, which includes the following steps:

[0083] (1) The matrix material was subjected to a first sand milling treatment according to the formula. The powder, sand milling balls and water were subjected to a first sand milling treatment for 60 minutes in a mass ratio of 1:6:0.55 to obtain powder with an average particle size of 0.85μm. Based on the total mass of the pre-fired material as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) was added and subjected to a first spray granulation treatment and a pre-fired treatment at 850℃ in a rotary kiln for 4 hours to obtain the pre-fired material.

[0084] (2) The additives and the pre-calcined material obtained in step (1) are subjected to a second sand milling treatment according to the formula amount. The powder, sand milling ball and water are subjected to a second sand milling treatment for 190 min in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.98 μm. Taking the total mass of the powder in the second sand milling treatment as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) is added and subjected to a second spray granulation treatment, compression molding treatment and sintering treatment at 1290℃ for 7 h in sequence to obtain the power ferrite material.

[0085] The AC resistance of the power ferrite materials obtained in Example 2 and Comparative Example 2 was measured, and the results are shown in Table 2:

[0086] Table 2

[0087]

[0088] As can be seen from the results in Table 2, the Co2O3 content is not within the preferred range of the present invention, resulting in a higher AC resistance of the power ferrite material under the conditions of 25°C, 200kHz and 0.5V.

[0089] Example 3

[0090] This embodiment provides a power ferrite material with a valley point of 15°C. The AC resistance of the power ferrite material is less than 235mΩ under the conditions of 25°C, 200kHz, and 0.5V. The power ferrite material is composed of a matrix material and additives.

[0091] The matrix material comprises, by mole percentage: 53.0 mol% Fe2O3, 37.0 mol% MnO and 10.0 mol% ZnO; the additives comprise, by total mass of the matrix material: 0.15% CaCO3 and 0.2% Co2O3.

[0092] This embodiment also provides a method for preparing the above-mentioned power ferrite material, which includes the following steps:

[0093] (1) The matrix material was subjected to a first sand milling treatment according to the formula. The powder, sand milling balls and water were milled for 60 minutes in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.86μm. Based on the total mass of the pre-fired material as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) was added and the material was subjected to a first spray granulation treatment and a pre-fired treatment at 850℃ in a rotary kiln for 3 hours to obtain the pre-fired material.

[0094] (2) The additives and the pre-calcined material obtained in step (1) are subjected to a second sand milling treatment according to the formula amount. The powder, sand milling ball and water are subjected to a second sand milling treatment for 180 min in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.96 μm. Taking the total mass of the powder in the second sand milling treatment as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) is added and subjected to a second spray granulation treatment, compression molding treatment and sintering treatment at 1290℃ for 6 h in sequence to obtain the power ferrite material.

[0095] Comparative Example 3

[0096] This comparative example provides a power ferrite material, which is composed of a matrix material and additives:

[0097] The matrix material comprises, by mole percentage: 53.0 mol% Fe2O3, 37.0 mol% MnO and 10.0 mol% ZnO; the additives comprise, by total mass of the matrix material: 0.05% CaCO3 and 0.2% Co2O3.

[0098] This comparative example also provides a method for preparing the above-mentioned power ferrite material, which includes the following steps:

[0099] (1) The matrix material was subjected to a first sand milling treatment according to the formula. The powder, sand milling balls and water were subjected to a first sand milling treatment for 60 minutes in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.84μm. Based on the total mass of the pre-fired material as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) was added and subjected to a first spray granulation treatment and a pre-fired treatment at 850℃ in a rotary kiln for 3 hours to obtain the pre-fired material.

[0100] (2) The additives and the pre-calcined material obtained in step (1) are subjected to a second sand milling treatment according to the formula amount. The powder, sand milling ball and water are subjected to a second sand milling treatment for 180 min in a mass ratio of 1:7:0.65 to obtain powder with an average particle size of 0.95 μm. Taking the total mass of the powder in the second sand milling treatment as 100%, a polyvinyl alcohol solution with a mass percentage of 10% (mass concentration of 7.5%) is added and subjected to a second spray granulation treatment, compression molding treatment and sintering treatment at 1290℃ for 6 h in sequence to obtain the power ferrite material.

[0101] The AC resistance of the power ferrite materials obtained in Example 3 and Comparative Example 3 was measured, and the results are shown in Table 3.

[0102] Table 3

[0103]

[0104] As can be seen from the results in Table 3, the CaCO3 content is not within the preferred range of the present invention, resulting in a higher AC resistance of the power ferrite material under the conditions of 25°C, 200kHz and 0.5V.

[0105] The applicant declares that the present invention is illustrated by the above embodiments, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A power ferrite material, characterized in that, The power ferrite material is composed of a matrix material and additives: The matrix material comprises, in mole percentage: Fe2O3 52.95-53.25 mol% MnO 36.55-37.05 mol% ZnO 9.7-10.5 mol% Based on the total mass of the matrix material as 100%, the additives include: CaCO3 0.13-0.18%; Co2O3 0.2-0.3%; The valley point of the power ferrite material is less than 25°C.

2. The power ferrite material according to claim 1, characterized in that, The valley point of the power ferrite material is 15°C.

3. The power ferrite material according to claim 1 or 2, characterized in that, The power ferrite material has an AC resistance of less than 235mΩ under the conditions of 25°C, 200kHz and 0.5V.

4. A method for preparing the power ferrite material according to claim 1, characterized in that, The method includes the following steps: (1) The matrix material is subjected to the first sand milling treatment, the first spray granulation treatment and the pre-calcination treatment in sequence according to the formula to obtain the pre-calcined material; (2) The additives and the pre-burned material obtained in step (1) are subjected to a second sand milling treatment, a second spray granulation treatment, a pressing and molding treatment and a sintering treatment in sequence according to the formula amount to obtain the power ferrite material.

5. The method according to claim 4, characterized in that, In step (1), the mass ratio of the first powder, the first grinding ball and the first grinding aid in the first sand milling process is 1:(6-8):(0.6-0.7).

6. The method according to claim 5, characterized in that, The first grinding aid includes water.

7. The method according to claim 4, characterized in that, The time for the first sand milling process in step (1) is 60-70 minutes.

8. The method according to claim 4, characterized in that, The average particle size of the powder after the first sand milling process in step (1) is 0.65μm-0.9μm.

9. The method according to claim 4, characterized in that, The mass concentration of the first adhesive used in the first spray granulation process in step (1) is 5%-15%.

10. The method according to claim 9, characterized in that, With the total mass of the pre-fired material described in step (1) being 100%, the mass percentage of the first adhesive is 10%.

11. The method according to claim 4, characterized in that, The pre-firing treatment in step (1) is carried out at a temperature of 850°C for 1-5 hours.

12. The method according to claim 4, characterized in that, In step (2), the mass ratio of the second powder, the second grinding ball and the second grinding aid in the second sand milling process is 1:(6-8):(0.6-0.7).

13. The method according to claim 12, characterized in that, The second grinding aid includes water.

14. The method according to claim 4, characterized in that, The second sand milling process in step (2) takes 150-240 minutes.

15. The method according to claim 4, characterized in that, The average particle size of the powder after the second sand milling process in step (2) is 0.95μm-1.15μm.

16. The method according to claim 4, characterized in that, The mass concentration of the second adhesive used in the second spray granulation process in step (2) is 5%-15%.

17. The method according to claim 16, characterized in that, With the total mass of powder in the second sand milling process described in step (2) being 100%, the mass percentage of the second adhesive is 10%.

18. The method according to claim 4, characterized in that, The sintering temperature in step (2) is 1260℃-1300℃, and the time is 5-7h.

19. An automotive electronic product, characterized in that, The automotive electronic product includes the power ferrite material according to any one of claims 1-3.

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