Dysprosium oxide coated samarium cobalt permanent magnetic material composite powder, preparation method and system device thereof

Abstract

The present invention provides a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder, a preparation method and a system device thereof, wherein the preparation method comprises: mixing samarium cobalt particles in a fluidized state with a dysprosium source and a reaction gas and reacting them, and obtaining the dysprosium oxide-coated samarium cobalt permanent magnet material composite powder after gas-solid separation of the reaction product. The present invention adopts a fluidization process, which not only allows the samarium cobalt powder to fully contact the dysprosium source and the reaction gas in a fluidized bed reaction device, but also provides a kinetic basis for subsequent full reaction, realizes uniform distribution of the powder at a microscopic scale, further ensures the uniformity of the permanent magnet at a macroscopic scale, and effectively improves the coercivity of the samarium cobalt permanent magnet material.

Description

Technical Field

[0001] The invention belongs to the technical field of magnetic materials, and relates to a dysprosium oxide-coated samarium cobalt permanent magnetic material composite powder, and a preparation method and system device thereof. Background Art

[0002] Samarium cobalt permanent magnet materials have both high Curie temperature (TC can reach 923℃) and excellent magnetic stability. They are the first choice in the field of high-temperature permanent magnet applications. They play an irreplaceable role in electronic communications, electronic interference and countermeasures, precision guidance and positioning, aerospace and other national defense equipment. They are one of the hot spots for cutting-edge technology development and strategic competition in countries around the world. In recent years, samarium cobalt permanent magnets have also begun to be used in high-power traction motors for subways and high-speed railways. With the rapid development of my country's rail transit and other industries, the demand for samarium cobalt permanent magnets will continue to grow in the future. Therefore, samarium cobalt permanent magnets are increasingly valued by the permanent magnet industry, and their production scale is gradually expanding in local areas where my country's permanent magnet industry is concentrated.

[0003] Samarium cobalt permanent magnets are precipitation hardening permanent magnet materials. Their hard magnetism originates from the unique nanocellular structure. The cell wall phase pins the domain wall movement of the cellular main phase, thereby improving the coercivity. Samarium cobalt permanent magnets have an uneven remagnetization process, so their squareness is lower than that of nucleation-type permanent magnet materials, resulting in the actual coercivity of samarium cobalt permanent magnets being less than 60% of the theoretical value. Therefore, how to improve the coercivity of samarium cobalt permanent magnet materials has become a major issue in the industry research field.

[0004] At present, an effective method to improve the coercive force of a magnet is to increase the anisotropy of the magnetic field by doping dysprosium oxide into the permanent magnetic material, which can effectively improve the coercive force of the magnet.

[0005] CN111161933A discloses a method for preparing a sintered samarium-cobalt permanent magnet with high coercivity and low temperature coefficient, comprising the following steps: (1) batching (2) melting and casting ingots (3) powdering (4) mixing (5) orientation molding (6) pre-sintering, sintering, and solid solution (7) slicing (8) solution preparation: mixing and stirring a dysprosium-containing material, anhydrous ethanol, and a dispersant to obtain a mixed solution; (9) coating: placing the samarium-cobalt alloy flakes obtained in step (7) in the mixed solution obtained in step (8), soaking, and drying; (10) dysprosium infiltration: placing the samarium-cobalt alloy flakes obtained after the treatment in step (9) in a vacuum heating furnace for vacuum infiltration; (11) aging treatment: performing aging treatment on the samarium-cobalt alloy flakes obtained after the treatment in step (10), cooling, and obtaining a samarium-cobalt permanent magnet.

[0006] It can be seen that how to design and prepare high-quality dysprosium oxide-coated samarium cobalt permanent magnet material composite powders to ensure uniform distribution of components on a microscopic scale has become an urgent problem to be solved in order to improve the coercive force of samarium cobalt permanent magnet materials. Summary of the invention

[0007] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder, a preparation method and a system device thereof. The present invention adopts a fluidization process not only to allow the samarium cobalt powder to fully contact with the dysprosium source and the reaction gas in the fluidized bed reaction device, but also to provide a kinetic basis for the subsequent full reaction, thereby achieving uniform distribution of the powder at the microscopic scale, further ensuring the uniformity of the permanent magnet at the macroscopic scale, and effectively improving the coercive force of the samarium cobalt permanent magnet material.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a method for preparing a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder, the preparation method comprising:

[0010] The samarium cobalt particles in a fluidized state are mixed with a dysprosium source and a reaction gas and reacted, and the dysprosium oxide-coated samarium cobalt permanent magnet material composite powder is obtained after gas-solid separation of the reaction product.

[0011] The fluidization process adopted in the present invention not only allows the samarium cobalt powder to fully contact with the dysprosium source and the reaction gas in the fluidized bed reaction device, but also provides a kinetic basis for subsequent full reaction, realizes uniform distribution of the powder at a microscopic scale, further ensures the uniformity of the permanent magnet at a macroscopic scale, and effectively improves the coercive force of the samarium cobalt permanent magnet material.

[0012] As a preferred technical solution of the present invention, the samarium cobalt particles are subjected to fluidization treatment in a protective atmosphere to obtain samarium cobalt particles in a fluidized state.

[0013] Preferably, the protective gas used in the protective atmosphere includes at least one of nitrogen, argon or helium, or a combination of two of them.

[0014] The invention can keep the samarium cobalt particles in a fluidized state and isolate oxygen in the environment by carrying out the reaction in a protective atmosphere, thereby facilitating the subsequent controllable coating of dysprosium oxide.

[0015] Preferably, the particle size of the samarium cobalt particles is 0.5 to 100 μm, for example, 0.5 μm, 1 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm or 100 μm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] As a preferred technical solution of the present invention, the mixing method is: the dysprosium source and the reaction gas are independently introduced into the protective atmosphere where the samarium cobalt particles in the fluidized state are located.

[0017] Preferably, the mixing temperature is 700-800°C, for example, it can be 700°C, 710°C, 720°C, 730°C, 740°C, 750°C, 760°C, 770°C, 780°C, 790°C or 800°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0018] Preferably, the mixing time is ≥1 min, for example, it can be 1 min, 2 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 9 min or 10 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0019] As a preferred technical solution of the present invention, the dysprosium source is DyCl3.

[0020] Preferably, the dysprosium source is preheated and then mixed for reaction.

[0021] Preferably, the dysprosium source is preheated to 718-1500°C, for example, it can be 718°C, 720°C, 750°C, 800°C, 850°C, 900°C, 950°C, 1000°C, 1050°C, 1100°C, 1150°C, 1200°C, 1250°C, 1300°C, 1350°C, 1400°C, 1450°C or 1500°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0022] Preferably, the dysprosium source is delivered into the reaction device via a carrier gas for a mixing reaction.

[0023] Preferably, the gas velocity after the dysprosium source and the carrier gas are mixed is 50 to 500 mL / min, for example, it can be 50 mL / min, 100 mL / min, 150 mL / min, 200 mL / min, 250 mL / min, 300 mL / min, 350 mL / min, 400 mL / min, 450 mL / min or 500 mL / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0024] As a preferred technical solution of the present invention, the reaction gas is water vapor.

[0025] Preferably, the reaction gases are preheated and then mixed for reaction.

[0026] Preferably, the reaction gas is preheated to 0-100°C, for example, 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C or 100°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0027] Preferably, the reaction gas is delivered into the reaction device via a carrier gas for mixed reaction.

[0028] Preferably, the gas velocity after the reaction gas and the carrier gas are mixed is 75 to 500 mL / min, for example, it can be 75 mL / min, 100 mL / min, 150 mL / min, 200 mL / min, 250 mL / min, 300 mL / min, 350 mL / min, 400 mL / min, 450 mL / min or 500 mL / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0029] The preparation method provided by the present invention limits the mixing time and mixing temperature, as well as the gas velocity at which the dysprosium source and the reaction gas are introduced into the fluidized bed reaction device. By adjusting the above process parameters, the purpose of uniformly depositing dysprosium oxide on the surface of the NdFeB permanent magnet material is achieved, and the dysprosium oxide content is regulated.

[0030] As a preferred technical solution of the present invention, the gas-solid separation method includes gravity sedimentation, centrifugal sedimentation or filtration.

[0031] As a preferred technical solution of the present invention, the preparation method comprises:

[0032] (I) fluidizing samarium-cobalt particles with a particle size of 0.5 to 100 μm in a protective atmosphere to obtain fluidized samarium-cobalt particles, wherein the protective atmosphere uses a protective gas comprising at least one of nitrogen, argon or helium, or a combination of two of these;

[0033] (II) preheating the dysprosium source to 718-1500°C, mixing the preheated dysprosium source with a carrier gas and introducing the mixture into the protective atmosphere of the fluidized samarium-cobalt particles at a gas velocity of 50-500 mL / min; at the same time, preheating the reaction gas to 0-100°C, mixing the preheated reaction gas with a carrier gas and introducing the mixture into the protective atmosphere of the fluidized samarium-cobalt particles at a gas velocity of 75-500 mL / min, the mixing temperature of the fluidized samarium-cobalt particles, the dysprosium source and the reaction gas being 700-800°C, and the mixing time being ≥1 min;

[0034] (III) After the reaction is completed, the reaction product is subjected to gravity sedimentation, centrifugal sedimentation or filtration to obtain a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder.

[0035] In a second aspect, the present invention provides a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder prepared by the preparation method described in the first aspect, wherein the mass fraction of dysprosium oxide in the dysprosium oxide-coated samarium cobalt permanent magnet material composite powder is 0.1 to 3.0 wt.%.

[0036] The dysprosium oxide coated samarium cobalt permanent magnet material composite powder provided by the present invention uses the chemical vapor deposition principle combined with fluidized bed process technology to uniformly coat the surface of samarium cobalt particles with a dysprosium oxide shell. The uniform distribution at the microscopic scale ensures the uniformity at the macroscopic scale, so as to improve the coercive force of the samarium cobalt permanent magnet material and ensure the uniformity of the macroscopic permanent magnet motor composition.

[0037] In a third aspect, the present invention provides a system device for preparing the dysprosium oxide-coated samarium cobalt permanent magnet material composite powder described in the first aspect, the system device comprising a fluidized bed reaction device, the bottom of the fluidized bed reaction device is externally connected to a protective gas inlet pipe, the lower part of the reaction device is independently externally connected to a dysprosium source generating device and a reaction gas inlet pipe, and the upper part of the fluidized bed reaction device is externally connected to a material bin.

[0038] As a preferred technical solution of the present invention, the top of the fluidized bed reaction device is externally connected to a tail gas treatment device.

[0039] Preferably, a vaporization device is provided on the reaction gas inlet pipe.

[0040] Preferably, the fluidized bed reaction device is externally connected to a product collecting device.

[0041] The system refers to an equipment system, a system device or a production device.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] (1) The fluidization process adopted in the present invention not only allows the samarium cobalt powder to fully contact with the dysprosium source and the reaction gas in the fluidized bed reaction device, but also provides a kinetic basis for subsequent full reaction, realizes uniform distribution of the powder at the microscopic scale, further ensures the uniformity of the permanent magnet at the macroscopic scale, and effectively improves the coercive force of the samarium cobalt permanent magnet material;

[0044] (2) The method for preparing the dysprosium oxide-coated samarium-cobalt composite powder of the present invention is simple, the coating layer is uniform, the thickness is controllable, the cost is low, and it is easy to mass produce on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A schematic diagram of the structure of a system device for preparing dysprosium oxide-coated samarium cobalt magnetic material composite powder provided in a specific embodiment of the present invention;

[0046] Among them, 1-silo; 2-fluidized bed reaction device; 3-dysprosium source generation device; 4-vaporization device; 5-product collection device; 6-tail gas treatment device;

[0047] Figure 2 This is a SEM image of the dysprosium oxide-coated samarium cobalt composite powder prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0048] It should be understood that, in the description of the present invention, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0049] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0050] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0051] In a specific embodiment, the present invention provides a system device for preparing a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder, the system device is as follows Figure 1 As shown, it includes a fluidized bed reaction device 2, the bottom of the fluidized bed reaction device 2 is externally connected to a protective gas inlet pipe, the lower part of the reaction device is independently externally connected to a dysprosium source generating device 3 and a reaction gas inlet pipe, and a vaporizing device 4 is arranged on the reaction gas inlet pipe. The upper part of the fluidized bed reaction device 2 is externally connected to a silo 1, the top of the fluidized bed reaction device 2 is externally connected to an exhaust gas treatment device 6, and the fluidized bed reaction device 2 is externally connected to a product collecting device 5.

[0052] In another specific embodiment, the present invention provides a method for preparing a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder, the preparation method comprising:

[0053] (1) Fluidizing samarium-cobalt particles with a particle size of 0.5 to 100 μm in a protective atmosphere to obtain fluidized samarium-cobalt particles, wherein the protective atmosphere uses a protective gas comprising at least one of nitrogen, argon or helium, or a combination of two of these;

[0054] (2) preheating the dysprosium source to 718-1500° C., mixing the preheated dysprosium source with a carrier gas, and introducing the preheated dysprosium source into the protective atmosphere of the fluidized samarium cobalt particles at a gas rate of 50-500 mL / min; at the same time, preheating the reaction gas to 0-100° C., mixing the preheated reaction gas with a carrier gas, and introducing the preheated reaction gas into the protective atmosphere of the fluidized samarium cobalt particles at a gas rate of 75-500 mL / min, the mixing temperature of the fluidized samarium cobalt particles, the dysprosium source, and the reaction gas is 700-800° C., and the mixing time is ≥1 min;

[0055] (3) After the reaction is completed, the reaction product is subjected to gravity sedimentation, centrifugal sedimentation or filtration to obtain a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder.

[0056] Example 1

[0057] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1 The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0058] (1) nitrogen is introduced into the fluidized bed reactor as a protective gas, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0059] (2) preheating the dysprosium source DyCl3 to 850°C and then feeding it into the fluidized bed reaction device 2 by the carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 60 mL / min; preheating the reaction gas to 60°C and then feeding it into the fluidized bed reaction device 2 by the carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 80 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 700°C, and the mixing time is 30 min;

[0060] (3) After the reaction is completed, the gas and solid are separated by gravity sedimentation to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 0.2 wt.%.

[0061] Figure 2 The SEM image of the dysprosium oxide-coated samarium-cobalt magnetic material composite powder prepared in this example is shown in FIG. Figure 2 It can be seen that the surface of the samarium cobalt powder is evenly coated with a layer of dysprosium oxide film.

[0062] Example 2

[0063] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0064] (1) introducing argon as a protective gas into a fluidized bed reaction chamber, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0065] (2) preheating the dysprosium source DyCl3 to 900°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 80 mL / min; preheating the reaction gas to 70°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 120 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 720°C, and the mixing time is 90 min;

[0066] (3) After the reaction is completed, centrifugal sedimentation is performed to separate the gas and solid to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 0.3 wt.%.

[0067] Example 3

[0068] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1 The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0069] (1) introducing helium as a protective gas into a fluidized bed reaction chamber, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0070] (2) preheating the dysprosium source DyCl3 to 1100°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 60 mL / min; preheating the reaction gas to 60°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 100 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 750°C, and the mixing time is 60 min;

[0071] (3) After the reaction is completed, the gas and solid are separated by filtration to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 0.5 wt.%.

[0072] Example 4

[0073] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0074] (1) nitrogen is introduced into the fluidized bed reactor as a protective gas, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0075] (2) preheating the dysprosium source DyCl3 to 1300°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 120 mL / min; preheating the reaction gas to 80°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 240 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 800°C, and the mixing time is 90 min;

[0076] (3) After the reaction is completed, the gas and solid are separated by gravity sedimentation to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 2.1 wt.%.

[0077] Example 5

[0078] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1 The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0079] (1) introducing argon as a protective gas into a fluidized bed reaction chamber, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0080] (2) preheating the dysprosium source DyCl3 to 900°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 100 mL / min; preheating the reaction gas to 60°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 200 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 770°C, and the mixing time is 90 min;

[0081] (3) After the reaction is completed, centrifugal sedimentation is performed to separate the gas and solid to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 1.5 wt.%.

[0082] Example 6

[0083] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0084] (1) introducing helium as a protective gas into a fluidized bed reaction chamber, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0085] (2) preheating the dysprosium source DyCl3 to 1400°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 160 mL / min; preheating the reaction gas to 80°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 80 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 300°C, and the mixing time is 120 min;

[0086] (3) After the reaction, the gas and solid are separated by filtration to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder. The dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 2.2 wt.%.

[0087] Example 7

[0088] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1 The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0089] (1) nitrogen is introduced into the fluidized bed reactor as a protective gas, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0090] (2) preheating the dysprosium source DyCl3 to 800°C and then feeding it into the fluidized bed reactor 2 by carrier gas, the mixed gas rate of the dysprosium source and the carrier gas being 150 mL / min; preheating the reaction gas to 60°C and then feeding it into the fluidized bed reactor 2 by carrier gas, the mixed gas rate of the reaction gas and the carrier gas being 320 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reactor 2, mixed with the samarium cobalt particles in the fluidized state, the mixing temperature being 730°C, and the mixing time being 90 min;

[0091] (3) After the reaction is completed, the gas and solid are separated by gravity sedimentation to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 1.4 wt.%.

[0092] Example 8

[0093] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0094] (1) introducing argon as a protective gas into a fluidized bed reaction chamber, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0095] (2) preheating the dysprosium source DyCl3 to 1200°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 80 mL / min; preheating the reaction gas to 50°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 140 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 760°C, and the mixing time is 30 min;

[0096] (3) After the reaction is completed, centrifugal sedimentation is performed to separate the gas and solid to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 0.3 wt.%.

[0097] Example 9

[0098] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1 The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0099] (1) introducing helium as a protective gas into a fluidized bed reaction chamber, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0100] (2) preheating the dysprosium source DyCl3 to 1000°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 100 mL / min; preheating the reaction gas to 50°C and then feeding it into the fluidized bed reaction device 2 by carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 200 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 800°C, and the mixing time is 45 min;

[0101] (3) After the reaction, the gas and solid are separated by filtration to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 0.7 wt.%.

[0102] Example 10

[0103] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0104] (1) introducing argon as a protective gas into a fluidized bed reaction chamber, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0105] (2) preheating the dysprosium source DyCl3 to 718°C and then feeding it into the fluidized bed reactor 2 by carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 50 mL / min; preheating the reaction gas to 10°C and then feeding it into the fluidized bed reactor 2 by carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 75 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reactor 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 700°C, and the mixing time is 60 min;

[0106] (3) After the reaction is completed, centrifugal sedimentation is performed to separate the gas and solid to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 0.1 wt.%.

[0107] Embodiment 11

[0108] This embodiment provides a method for preparing a dysprosium oxide-coated samarium-cobalt magnetic material composite powder. The preparation method is provided in the present invention as follows Figure 1 The preparation method is carried out in the system device shown in the figure, and the preparation method comprises the following steps:

[0109] (1) introducing argon as a protective gas into a fluidized bed reaction chamber, so that samarium cobalt particles with a particle size of 1 to 3 μm are in a fluidized state in the protective atmosphere;

[0110] (2) preheating the dysprosium source DyCl3 to 1500°C and then feeding it into the fluidized bed reaction device 2 by the carrier gas, and the mixed gas rate of the dysprosium source and the carrier gas is 500 mL / min; preheating the reaction gas to 100°C and then feeding it into the fluidized bed reaction device 2 by the carrier gas, and the mixed gas rate of the reaction gas and the carrier gas is 500 mL / min; the dysprosium source and the reaction gas are simultaneously introduced into the fluidized bed reaction device 2, and mixed with the samarium cobalt particles in the fluidized state, the mixing temperature is 800°C, and the mixing time is 1 min;

[0111] (3) After the reaction is completed, centrifugal sedimentation is performed to separate the gas and solid to obtain a dysprosium oxide-coated samarium cobalt magnetic material composite powder, wherein the dysprosium oxide content of the dysprosium oxide-coated samarium cobalt magnetic material composite powder is 0.3 wt.%.

[0112] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder, characterized in that: The preparation method comprises: The samarium cobalt particles in a fluidized state are mixed with a dysprosium source and a reaction gas and reacted, and the reaction product is separated into gas and solid to obtain the dysprosium oxide-coated samarium cobalt permanent magnet material composite powder; The particle size of the samarium cobalt particles is 0.5-100 μm; The mixing temperature is 700-800°C; The dysprosium source is sent into the reaction device through a carrier gas for mixed reaction, and the gas velocity after the dysprosium source and the carrier gas are mixed is 50-500 mL / min; The reaction gas is sent into the reaction device through the carrier gas for mixed reaction; the gas velocity after the reaction gas and the carrier gas are mixed is 75-500 mL / min; The samarium-cobalt particles are subjected to fluidization treatment in a protective atmosphere to obtain samarium-cobalt particles in a fluidized state; The dysprosium source is DyCl3; The dysprosium source is preheated and then mixed for reaction; The dysprosium source is preheated to 718-1500°C; The reaction gas is water vapor.

2. The preparation method according to claim 1, characterized in that: The protective gas used in the protective atmosphere includes at least one of nitrogen, argon or helium, or a combination of two of them.

3. The preparation method according to claim 1, characterized in that: The mixing method is: the dysprosium source and the reaction gas are independently introduced into the protective atmosphere where the samarium cobalt particles in the fluidized state are located.

4. The preparation method according to claim 1, characterized in that: The mixing time is ≥1 min.

5. The preparation method according to claim 1, characterized in that: The reaction gases are mixed and reacted after being preheated.

6. The preparation method according to claim 5, characterized in that: The reaction gas is preheated to 0-100°C.

7. The preparation method according to claim 1, characterized in that: The gas-solid separation method includes gravity sedimentation, centrifugal sedimentation or filtration.

8. The preparation method according to claim 1, characterized in that: The preparation method comprises: (I) fluidizing samarium cobalt particles with a particle size of 0.5 to 100 μm in a protective atmosphere to obtain fluidized samarium cobalt particles, wherein the protective atmosphere uses a protective gas comprising at least one of nitrogen, argon or helium, or a combination of two of these; (II) preheating the dysprosium source to 718-1500°C, mixing the preheated dysprosium source with a carrier gas and introducing the mixture into the protective atmosphere of the fluidized samarium-cobalt particles at a gas velocity of 50-500 mL / min; at the same time, preheating the reaction gas to 0-100°C, mixing the preheated reaction gas with a carrier gas and introducing the mixture into the protective atmosphere of the fluidized samarium-cobalt particles at a gas velocity of 75-500 mL / min, the mixing temperature of the fluidized samarium-cobalt particles, the dysprosium source and the reaction gas being 700-800°C, and the mixing time being ≥1 min; (III) After the reaction is completed, the reaction product is subjected to gravity sedimentation, centrifugal sedimentation or filtration to obtain a dysprosium oxide-coated samarium cobalt permanent magnet material composite powder.

9. The preparation method according to claim 1, characterized in that: The reaction device comprises a fluidized bed reaction device, the bottom of the fluidized bed reaction device is externally connected to a protective gas inlet pipe, the lower part of the reaction device is independently externally connected to a dysprosium source generating device and a reaction gas inlet pipe, and the upper part of the fluidized bed reaction device is externally connected to a material bin.

10. The preparation method according to claim 9, characterized in that: The top of the fluidized bed reaction device is externally connected to a tail gas treatment device.

11. The preparation method according to claim 9, characterized in that: The reaction gas inlet pipe is provided with a vaporization device.

12. The preparation method according to claim 9, characterized in that: The fluidized bed reaction device is externally connected to a product collecting device.

13. A dysprosium oxide-coated samarium cobalt permanent magnet material composite powder prepared by the preparation method according to any one of claims 1 to 12, characterized in that: The mass fraction of dysprosium oxide in the dysprosium oxide-coated samarium cobalt permanent magnet material composite powder is 0.1-3.0wt.%.

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