A method for preparing high-performance permanent magnet ferrite

Abstract

This invention discloses a method for preparing high-performance permanent magnet ferrites. The method includes the following steps: placing pre-calcined permanent magnet ferrite powder in a ball mill jar, adding calcium carbonate, sodium bicarbonate, tungsten oxide, barium carbonate, and silicon micropowder, mixing evenly to form a mixture, adding water to the mixture, and ball milling to prepare a slurry. The slurry is then filtered through sedimentation to prepare a molding slurry. The molding slurry is then molded to obtain a green blank. The green blank is then sintered to obtain a permanent magnet ferrite magnet blank. This invention provides a method for preparing high-performance permanent magnet ferrites that improves the remanence of permanent magnet ferrites while maintaining high intrinsic coercivity.

Description

Technical Field

[0001] This invention belongs to the field of magnetic materials technology, and in particular relates to a method for preparing high-performance permanent magnet ferrite. Background Technology

[0002] In recent years, with the miniaturization, lightweighting, and thinning of permanent magnet motors, and the increasing demands for environmental protection and energy conservation, higher requirements have been placed on the magnetic properties of permanent magnet ferrites, a key magnetic source component of permanent magnet motors. Exploring and developing high-performance permanent magnet ferrite materials and their preparation technologies is of significant innovative importance for improving the structural composition of current high-end ferrite products and has always been a key focus in the field of magnetic materials research.

[0003] Currently, the preparation method of permanent magnet ferrite usually includes the following steps: (1) adding the pre-burned permanent magnet ferrite material into a ball mill, and adding additives such as calcium carbonate, quartz sand, metallic chromium powder and calcium gluconate into the ball mill; (2) adding water into the ball mill and ball milling to obtain a permanent magnet ferrite slurry; (3) precipitating and filtering the permanent magnet ferrite slurry obtained in step (2) to obtain a permanent magnet ferrite filter slurry; (4) injecting the permanent magnet ferrite filter slurry obtained in step (3) into a mold and pressing it under a magnetic field to obtain a permanent magnet ferrite green body; (5) heating and sintering the permanent magnet ferrite green body obtained in step (4) to obtain a permanent magnet ferrite product.

[0004] Several challenges exist in the preparation process, such as how to improve the magnetic properties of permanent magnet ferrites. Current technologies have limited research on the effects of additive types and content, as well as ball milling time, on the magnetic properties of permanent magnet ferrites, and the optimal combination of these factors remains undetermined. Therefore, further research and optimization of methods to improve the magnetic properties of permanent magnet ferrites are necessary. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned problems in the prior art and provide a method for preparing high-performance permanent magnet ferrites that can both improve the remanence of permanent magnet ferrites and maintain high intrinsic coercivity.

[0006] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0007] A method for preparing high-performance permanent magnet ferrite includes the following steps: placing pre-calcined permanent magnet ferrite powder in a ball mill jar, adding calcium carbonate, sodium bicarbonate, tungsten oxide, barium carbonate, and silicon micro powder respectively, mixing evenly to form a mixture, adding water to the mixture, and ball milling to prepare a mixed slurry, filtering the mixed slurry through sedimentation to prepare a molding slurry, molding the molding slurry through injection molding to prepare a molded green body, and sintering the molded green body to prepare a permanent magnet ferrite magnet blank;

[0008] The amount of calcium carbonate added is 0.05-1.2 wt% of the pre-sintered permanent magnet ferrite powder, the amount of sodium bicarbonate added is 0.1-1.0 wt% of the pre-sintered permanent magnet ferrite powder, the amount of tungsten oxide added is 0.01-0.5 wt% of the pre-sintered permanent magnet ferrite powder, the amount of barium carbonate added is 0.05-2.0 wt% of the pre-sintered permanent magnet ferrite powder, and the amount of silicon micropowder added is 0.1-0.9 wt% of the pre-sintered permanent magnet ferrite powder.

[0009] Furthermore, the amount of calcium carbonate added is 0.20-1.0 wt% of the pre-sintered permanent magnet ferrite powder, the amount of sodium bicarbonate added is 0.3-0.6 wt% of the pre-sintered permanent magnet ferrite powder, the amount of tungsten oxide added is 0.25-0.45 wt% of the pre-sintered permanent magnet ferrite powder, the amount of barium carbonate added is 0.15-0.35 wt% of the pre-sintered permanent magnet ferrite powder, and the amount of silica powder added is 0.2-0.6 wt% of the pre-sintered permanent magnet ferrite powder.

[0010] Furthermore, the amount of calcium carbonate added is 0.60 wt% of the pre-sintered permanent magnet ferrite powder, the amount of sodium bicarbonate added is 0.45 wt% of the pre-sintered permanent magnet ferrite powder, the amount of tungsten oxide added is 0.35 wt% of the pre-sintered permanent magnet ferrite powder, the amount of barium carbonate added is 0.25 wt% of the pre-sintered permanent magnet ferrite powder, and the amount of silicon micropowder added is 0.40 wt% of the pre-sintered permanent magnet ferrite powder.

[0011] Furthermore, the specific process of ball milling is as follows: deionized water is added to the mixture in the ball milling jar, and the mixture is ball milled until the average particle size is 0.60-1.10 μm to prepare a mixed slurry.

[0012] Furthermore, the amount of deionized water added is 130-250 wt% of the mixture.

[0013] Furthermore, the specific process of the sedimentation filtration is as follows: the mixed slurry is sedimented for 0.5-1h, the supernatant is removed, and the sediment is squeezed and filtered until the water content is 28-32wt% to prepare the shaped slurry.

[0014] Furthermore, the specific process of injection molding is as follows: the molding slurry is injected into the mold, and pressure is applied at 7-10MPa under a magnetic field strength of 10000-15000Gs to obtain the molded green blank.

[0015] Furthermore, the specific sintering process is as follows: the formed green blank is placed in an electric kiln for sintering to obtain a permanent magnet ferrite blank.

[0016] Furthermore, during the sintering process, the sintering temperature is 1180-1230℃ and the sintering time is 0.5-2h.

[0017] Furthermore, in step a, the permanent magnet ferrite pre-sintered powder is SM12 pre-sintered material produced by Longci Technology.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] 1. This invention provides a method for preparing high-performance permanent magnet ferrite. By designing a reasonable formula and determining the types and amounts of additives, the remanence of the permanent magnet ferrite can be improved while maintaining a high intrinsic coercivity.

[0020] 2. This invention adds calcium carbonate and silicon micropowder to the pre-sintered ferrite powder of permanent magnets. At high temperature, the powder decomposes into calcium silicate, which has a melting effect and is conducive to solid-phase reaction. This increases the density of the sintered body and thus improves remanence and intrinsic coercivity. Carbon dioxide is generated during the reaction, and the release of carbon dioxide increases the reactivity between particles.

[0021] 3. The present invention also adds sodium bicarbonate to the pre-sintered powder of permanent magnet ferrite. Sodium bicarbonate will continuously decompose carbon dioxide during the sintering process. The release of carbon dioxide will increase the interparticle reaction activity. Sodium oxide has high activity, which promotes the stability of the M-type hexagonal crystal phase and makes the microstructure of the particles present a more standard hexagon.

[0022] 4. The present invention adds tungsten oxide to the pre-calcined powder of permanent magnet ferrite, which can quickly fill the particle surface, improve the density and increase the micro-binding effect, that is, increase the difficulty of deflection after particle orientation and increase the intrinsic force.

[0023] 5. The present invention reduces the gap between grains by adding barium carbonate to the pre-calcined ferrite powder of permanent magnets, which is conducive to the shrinkage and convergence of grains, increases density, and thus improves remanence and intrinsic coercivity.

[0024] 6. This invention, by simultaneously adding calcium carbonate, sodium bicarbonate, tungsten oxide, barium carbonate, and silicon micropowder during ball milling, obtains a product with superior magnetic properties compared to products obtained by adding calcium carbonate, sodium bicarbonate, tungsten oxide, barium carbonate, and silicon micropowder alone. Furthermore, the magnetic properties of the permanent magnet ferrite are significantly improved, resulting in a high-performance permanent magnet ferrite with a remanence (Br) of 4520-4760 GS and an intrinsic coercivity (Hcj) of 5100-5850 e. Attached Figure Description

[0025] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0026] Figure 1 This is a flowchart of the preparation method of high-performance permanent magnet ferrite provided by the present invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1

[0029] like Figure 1 As shown in the figure, this embodiment provides a method for preparing high-performance permanent magnet ferrite, which includes the following steps:

[0030] Step 1.1:

[0031] Ingredients: Select 1 kg of permanent magnet ferrite pre-sintered powder. The permanent magnet ferrite pre-sintered powder is SM12 pre-sintered powder produced by Longci Technology (main component is Fe2O3). Place 1 kg of permanent magnet ferrite pre-sintered powder as the main raw material in a ball mill jar, and add 6.1 g of calcium carbonate, 4.1 g of sodium bicarbonate, 3.7 g of tungsten oxide, 2.4 g of barium carbonate and 4.1 g of silicon micro powder in sequence to obtain a mixture.

[0032] Step 1.2:

[0033] Ball milling: Add 2 kg of water to the mixture obtained in step 1.1 and ball mill until the average particle size is 0.72 μm to obtain a mixed slurry;

[0034] Step 1.3:

[0035] Sedimentation and filtration: The mixed slurry obtained in step 1.2 is settled in a sedimentation tower for 0.8 hours and dehydrated to a water content of 30 wt% to obtain a shaped slurry;

[0036] Step 1.4:

[0037] Injection molding: The molding slurry obtained in step 1.3 is injected into the mold, and the mold is subjected to a magnetic field strength of 12000.

[0038] Under the condition of Gs, the green blank is formed into a round cake with a diameter of Φ40.2mm by applying a pressure of 9MPa in a 100T wet forming press.

[0039] Step 1.5:

[0040] Sintering: The green blank obtained in step 1.4 is placed in an electric kiln and sintered at 1210℃ for 1 hour to obtain a permanent magnet ferrite blank.

[0041] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this embodiment were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0042] Example 2

[0043] This embodiment provides a method for preparing high-performance permanent magnet ferrite, the method comprising the following steps:

[0044] Step 2.1: Batching: Select 1 kg of permanent magnet ferrite pre-sintered powder. The permanent magnet ferrite pre-sintered powder is SM12 pre-sintered powder produced by Longci Technology (main component is Fe2O3). Place 1 kg of permanent magnet ferrite pre-sintered powder as the main raw material in a ball mill jar, and add 5.3 g of calcium carbonate, 3.2 g of sodium bicarbonate, 1.5 g of tungsten oxide, 1.5 g of barium carbonate and 3.2 g of silicon micro powder in sequence to obtain a mixture.

[0045] Step 2.2:

[0046] Ball milling: Add 2 kg of water to the mixture obtained in step 2.1 and ball mill until the average particle size is 0.93 μm to obtain a mixed slurry;

[0047] Step 2.3:

[0048] Sedimentation and filtration: The mixed slurry obtained in step 2.2 is settled in a sedimentation tower for 0.5 hours and dehydrated to a water content of 29 wt% to obtain a shaped slurry;

[0049] Step 2.4:

[0050] Injection molding: The molding slurry obtained in step 2.3 is injected into the mold, and the mold is then subjected to a magnetic field strength of 10000.

[0051] Under the condition of Gs, the green blank is formed into a round cake with a diameter of Φ40.2mm by applying a pressure of 9MPa in a 100T wet forming press.

[0052] Step 2.5:

[0053] Sintering: The green blank obtained in step 2.4 is placed in an electric kiln and sintered at 1200℃ for 1 hour to obtain a permanent magnet ferrite magnet blank.

[0054] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this embodiment were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0055] Example 3

[0056] This embodiment provides a method for preparing high-performance permanent magnet ferrite, the method comprising the following steps:

[0057] Step 3.1:

[0058] Ingredients: Select 1 kg of permanent magnet ferrite pre-sintered powder. The permanent magnet ferrite pre-sintered powder is SM12 pre-sintered powder produced by Longci Technology (main component is Fe2O3). Place 1 kg of permanent magnet ferrite pre-sintered powder as the main raw material in a ball mill jar, and add 7.5 g of calcium carbonate, 2.4 g of sodium bicarbonate, 10 g of tungsten oxide, 4 g of barium carbonate and 5.4 g of silicon micro powder in sequence to obtain a mixture.

[0059] Step 3.2:

[0060] Ball milling: Add 1.8 kg of water to the mixture obtained in step 3.1 and ball mill until the average particle size is 0.75 μm to obtain a mixed slurry;

[0061] Step 3.3:

[0062] Sedimentation and filtration: The mixed slurry obtained in step 3.2 is settled in a sedimentation tower for 1 hour and dehydrated to a water content of 31 wt% to obtain a shaped slurry;

[0063] Step 3.4:

[0064] Injection molding: The molding slurry obtained in step 3.3 is injected into the mold, and the mold is then subjected to a magnetic field strength of 11000.

[0065] Under the condition of Gs, the material is pressed at 8.5MPa in a 100T wet forming press to form a round cake with a diameter of Φ40.2mm, thus obtaining the formed green blank;

[0066] Step 3.5:

[0067] Sintering: The green blank obtained in step 3.4 is placed in an electric kiln and sintered at 1210℃ for 1 hour to obtain a permanent magnet ferrite magnet blank.

[0068] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this embodiment were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0069] Example 4

[0070] This embodiment provides a method for preparing high-performance permanent magnet ferrite, the method comprising the following steps:

[0071] Step 4.1:

[0072] Ingredients: Select 1 kg of permanent magnet ferrite pre-sintered powder, which is SM12 pre-sintered powder (main component is Fe2O3) produced by Longci Technology. Place 1 kg of permanent magnet ferrite pre-sintered powder as the main raw material in a ball mill jar, and then add 10.1 g of calcium carbonate, 1.6 g of sodium bicarbonate, 1.16 g of tungsten oxide, 6.2 g of barium carbonate and 3.0 g of silicon micro powder in sequence to obtain a mixture.

[0073] Step 4.2:

[0074] Ball milling: Add 1.8 kg of water to the mixture obtained in step 4.1 and ball mill until the average particle size is 0.75 μm to obtain a mixed slurry;

[0075] Step 4.3:

[0076] Sedimentation and filtration: The mixed slurry obtained in step 4.2 is settled in a sedimentation tower for 1 hour and dehydrated to a water content of 30 wt% to obtain a shaped slurry;

[0077] Step 4.4:

[0078] Injection molding: The molding slurry obtained in step 4.3 is injected into the mold, and the mold is then subjected to a magnetic field strength of 11500.

[0079] Under the condition of Gs, the green blank is formed into a round cake with a diameter of Φ40.2mm by applying a pressure of 9MPa in a 100T wet forming press.

[0080] Step 4.5:

[0081] Sintering: The green blank obtained in step 4.4 is placed in an electric kiln and sintered at 1200℃ for 1 hour to obtain a permanent magnet ferrite magnet blank.

[0082] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this embodiment were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0083] Comparative Example 1

[0084] This comparative example uses the same main raw materials and process as Example 1, the only difference being that no ingredients are added to 1 kg of pre-calcined permanent magnet ferrite powder during ball milling.

[0085] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this comparative example were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0086] Comparative Example 2

[0087] This comparative example uses the same main raw materials and basically the same process as Example 1. The only difference is that only calcium carbonate is added to 1 kg of permanent magnet ferrite pre-calcined powder during ball milling, and the amount of calcium carbonate added is 8 g.

[0088] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this comparative example were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0089] Comparative Example 3

[0090] This comparative example uses the same main raw materials and basically the same process as Example 1. The only difference is that sodium bicarbonate is added to 1 kg of permanent magnet ferrite pre-calcined powder during ball milling, and the amount of sodium bicarbonate added is 5 g.

[0091] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this comparative example were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0092] Comparative Example 4

[0093] This comparative example uses the same main raw materials and basically the same process as Example 1. The only difference is that tungsten oxide is added to 1 kg of permanent magnet ferrite pre-calcined powder during ball milling, and the amount of tungsten oxide added is 2 g.

[0094] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this comparative example were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0095] Comparative Example 5

[0096] This comparative example uses the same main raw materials and basically the same process as Example 1. The only difference is that barium carbonate is added to 1 kg of permanent magnet ferrite pre-calcined powder during ball milling, and the amount of barium carbonate added is 6 g.

[0097] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this comparative example were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0098] Comparative Example 6

[0099] This comparative example uses the same main raw materials and basically the same process as Example 1. The only difference is that only silicon micropowder is added to 1 kg of permanent magnet ferrite pre-sintered powder during ball milling, and the amount of silicon micropowder added is 3.5 g.

[0100] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this comparative example were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0101] Comparative Example 7

[0102] This comparative example uses the same main raw materials and basically the same process as Example 1. The only difference is that calcium carbonate and silicon micro powder are added to 1 kg of permanent magnet ferrite pre-calcined powder during ball milling. The amount of calcium carbonate and silicon micro powder added is 6 g and 3.5 g, respectively.

[0103] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this comparative example were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0104] Comparative Example 8

[0105] This comparative example uses the same main raw materials and essentially the same process as Example 1, the only difference being that it uses the standard formula provided by the raw material manufacturer.

[0106] Specifically, 8g of calcium carbonate, 4g of silicon dioxide, 3g of sorbitol, 1.5g of strontium carbonate, and 1g of cobalt oxide are added to 1kg of permanent magnet ferrite pre-fired powder.

[0107] The upper and lower surfaces of the permanent magnet ferrite blank obtained in this comparative example were ground and polished. The magnetic properties of the product were tested using the FE-2100H-A type automatic magnetic material measuring device of Hunan Yongyi Technology. The test results are shown in Table 1.

[0108] The permanent magnet ferrite pre-sintered powders in Comparative Examples 1-8 were all SM12 pre-sintered powders (mainly Fe2O3) produced by Longci Technology.

[0109] Table 1. Comparison of magnetic properties of permanent magnet ferrite magnet blanks obtained in Examples 1-4 and Comparative Examples 1-8

[0110]

[0111] As shown in Table 1, the permanent magnet ferrites prepared by this method for high-performance permanent magnet ferrites exhibit improved remanence and intrinsic coercivity compared to the comparative example. Specifically, the product without the addition of calcium carbonate, sodium bicarbonate, tungsten oxide, barium carbonate, and silicon powder has the worst remanence and intrinsic coercivity. The product with only the addition of calcium carbonate, sodium bicarbonate, tungsten oxide, barium carbonate, and silicon powder shows improved remanence and intrinsic coercivity compared to the product without these additives. Furthermore, the product with the simultaneous addition of calcium carbonate, sodium bicarbonate, tungsten oxide, barium carbonate, and silicon powder significantly improves both remanence and intrinsic coercivity.

[0112] Calcium carbonate and silica powder were added to the pre-sintered ferrite powder for permanent magnets. Calcium carbonate decomposes into calcium oxide and carbon dioxide at high temperatures. Calcium oxide and silica powder react at high temperatures to form calcium silicate. This reaction is a solid-state reaction at high temperatures, which usually needs to be carried out above 1200℃. Calcium silicate has a melting effect, which is beneficial to the solid-state reaction and increases the density of the sintered body, thereby improving remanence and intrinsic coercivity. The carbon dioxide (CO2) released during the reaction increases the interparticle reactivity and promotes the sintering process.

[0113] Adding sodium bicarbonate to the pre-sintered powder of permanent magnet ferrite can help because sodium bicarbonate continuously decomposes into carbon dioxide during sintering. The continuously decomposed carbon dioxide (CO2) increases the interparticle reactivity. The sodium oxide (Na2O) continuously generated during the reaction has high activity, which promotes the stability of the M-type hexagonal crystal phase and makes the microstructure of the particles present a more standard hexagonal shape.

[0114] Adding tungsten oxide to the pre-sintered powder of permanent magnet ferrite can quickly fill the particle surface, improve the density and increase the micro-binding effect, that is, increase the difficulty of deflection after particle orientation, increase the intrinsic force, and further increase the corrosion resistance of permanent magnet ferrite, thereby improving its service life and stability.

[0115] Adding barium carbonate to the pre-sintered ferrite powder of permanent magnets can reduce the gap between grains, which is conducive to the shrinkage and convergence of grains, increases density, and thus improves remanence and intrinsic coercivity.

[0116] This invention provides a method for preparing high-performance permanent magnet ferrites. By adding various additives to pre-calcined permanent magnet ferrite powder, it has been found that the type and content of additives have a significant impact on the performance of permanent magnet ferrites. Through various combinations, the type and amount of additives were determined, thereby effectively improving the remanence and intrinsic coercivity of permanent magnet ferrites. The permanent magnet ferrites prepared by this invention have effectively improved performance, quality and stability.

[0117] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0118] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A method of producing a high-performance permanent ferrite, characterized by, The method comprises the following steps: placing permanent magnet ferrite pre-fired material powder in a ball mill tank, adding calcium carbonate, sodium bicarbonate, tungsten oxide, barium carbonate and silicon powder respectively, mixing uniformly to prepare a mixture, adding water to the mixture, preparing a mixed slurry through ball milling, preparing a forming slurry through sedimentation and filtration of the mixed slurry, preparing a forming green body through injection molding of the forming slurry, and preparing a permanent magnet ferrite magnet blank through sintering of the forming green body. The adding amount of the calcium carbonate is 0.20-1.0wt% of the permanent magnet ferrite pre-fired material powder, the adding amount of the sodium bicarbonate is 0.3-0.6wt% of the permanent magnet ferrite pre-fired material powder, the adding amount of the tungsten oxide is 0.25-0.45wt% of the permanent magnet ferrite pre-fired material powder, the adding amount of the barium carbonate is 0.15-0.35wt% of the permanent magnet ferrite pre-fired material powder, and the adding amount of the silicon powder is 0.2-0.6wt% of the permanent magnet ferrite pre-fired material powder. The specific process of the injection molding is as follows: the forming slurry is injected into a mold, and pressure forming is carried out under the condition of a magnetic field intensity of 10000-15000Gs and a pressure of 7-10MPa to obtain the forming green body.

2. The method of claim 1, wherein the high-performance permanent ferrite is prepared by the steps of: The adding amount of the calcium carbonate is 0.60wt% of the permanent magnet ferrite pre-fired material powder, the adding amount of the sodium bicarbonate is 0.45wt% of the permanent magnet ferrite pre-fired material powder, the adding amount of the tungsten oxide is 0.35wt% of the permanent magnet ferrite pre-fired material powder, the adding amount of the barium carbonate is 0.25wt% of the permanent magnet ferrite pre-fired material powder, and the adding amount of the silicon powder is 0.40wt% of the permanent magnet ferrite pre-fired material powder. ​ 3. The method of claim 1, wherein the high-performance permanent ferrite is prepared by the steps of: The specific process of the ball milling is as follows: deionized water is added to the mixture in the ball mill tank, and the mixture is ball milled to an average particle size of 0.60-1.10μm to obtain the mixed slurry. ​ 4. The method of claim 3, wherein the high-performance permanent ferrite is prepared by the steps of: The adding amount of the deionized water is 130-250wt% of the mixture. ​ 5. The method of claim 1, wherein the high-performance permanent ferrite is prepared by the steps of: The specific process of the sedimentation and filtration is as follows: the mixed slurry is subjected to sedimentation treatment for 0.5-1h, the supernatant is removed, and the sediment is subjected to extrusion filtration until the water content is 28-32wt% to obtain the forming slurry. ​ 6. The method of claim 1, wherein the high-performance permanent ferrite is prepared by the steps of: The specific process of the sintering is as follows: the forming green body is placed in an electric kiln for sintering to obtain the permanent magnet ferrite magnet blank. ​ 7. The method of claim 6, wherein the high-performance permanent ferrite is prepared by the steps of: In the sintering process, the sintering temperature is 1180-1230℃, and the sintering time is 0.5-2h. ​ 8. The method of claim 1, wherein the high-performance permanent ferrite is prepared by the steps of: In step a, the permanent magnet ferrite pre-fired material powder is SM12 pre-fired material produced by Longji Science and Technology. ​

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