High-coercivity samarium-iron-based rare earth permanent magnet material and preparation method thereof

Abstract

The invention belongs to the technical field of rare earth permanent magnet materials, and relates to a high-coercivity samarium-iron-based rare earth permanent magnet material and a preparation method thereof. The chemical formula of the samarium-iron-based rare earth permanent magnet material is SmaFebCocTidMe, 0.5 < = a < = 1, 7.5 < = b < = 9, 0 < = c < = 3.0, 0.5 < = d < = 1.5, 0.1 < = e < = 2.0, and M is selected from one or more of Zr, Y, Gd, Ho and Ce; the high-coercivity samarium-iron-based rare earth permanent magnet material comprises a samarium-iron matrix main phase and a (Fe, Co) 2Ti phase. The invention also discloses a preparation method of the high-coercivity samarium-iron-based rare earth permanent magnet material, an amorphous precursor is enabled to inhibit massive precipitation of alpha-Fe through a melting and rapid quenching process, then short-time vacuum heat treatment is performed, and then a key element M is added, so that the grain size can be further refined, and the coercivity of the samarium-iron-based rare earth permanent magnet material is improved. The saturation magnetization and coercive force of the samarium-iron-based rare earth permanent magnet material are improved to different extents.

Description

Technical Field

[0001] The present invention belongs to the technical field of rare earth permanent magnet materials, and relates to a samarium-iron-based rare earth permanent magnet material with high coercivity and a preparation method thereof. Background Art

[0002] Permanent magnets are one of the key materials in green energy technologies such as electric vehicles and wind turbines. With the development of green technologies, the requirement for high-efficiency power conversion is further improved, and the demand for magnetic materials is further increased. Although neodymium-iron-boron-based rare earth permanent magnet materials solve the above problems to a certain extent, they will demagnetize when working at high temperatures, resulting in a significant reduction in coercivity and making it difficult to meet certain special requirements. Therefore, there is an urgent need to develop a new rare earth permanent magnet material that is superior to neodymium-iron-boron-based materials at high temperatures. The ThMn 12 -type Fe-rich SmFe 12 -based compounds have long been widely concerned due to their low rare earth usage and excellent intrinsic properties.

[0003] The crystal structure of ThMn 12 compounds belongs to the tetragonal space group I4 / mmm. Since binary SmFe 12 is thermodynamically unstable, elements such as Ti, V, Cr, and Mn need to be introduced to stabilize the ReFe 12 phase. The current difficulty in preparation is that the actual coercivity of the samarium-iron-based permanent magnet with ThMn 12 -type structure is quite different from the theoretical coercivity, and the coercivity has not reached 10% of the anisotropy field. Therefore, how to convert excellent intrinsic properties into extrinsic properties remains a difficult problem. Generally, high coercivity in rare earth permanent magnet materials is achieved through the following methods: (1) reducing the grain size; (2) performing exchange decoupling by forming a non-ferromagnetic intergranular phase; (3) eliminating interface defects that cause local reduction of magnetic crystal anisotropy at grain boundaries and interfaces; However, the current preparation process of samarium-iron-based permanent magnets with ThMn 12 -type structure still faces technical difficulties. Summary of the Invention

[0004] The purpose of the present invention is to address the above problems existing in the prior art and propose a samarium-iron-based rare earth permanent magnet material with a small grain size and high coercivity prepared by combining the rapid quenching method and the heat treatment method.

[0005] One object of the present invention is achieved by the following technical solutions:

[0006] A samarium-iron-based rare earth permanent magnet material with high coercivity, with the chemical formula Sm a Fe b Co c Ti d M e, where 0.5 ≤ a ≤ 1, 7.5 ≤ b ≤ 9, 0 ≤ c ≤ 3.0, 0.5 ≤ d ≤ 1.5, 0.1 ≤ e ≤ 2.0, and M is selected from one or more of Zr, Y, Gd, Ho, Ce;

[0007] The high coercivity samarium-iron-based rare earth permanent magnet material includes a samarium-iron matrix main phase and a (Fe,Co)2Ti phase.

[0008] Preferably, (a + e):(b + c + d) = 1:12.

[0009] Preferably, a + e + d < c.

[0010] Preferably, the volume fraction of the samarium-iron matrix main phase in the high coercivity samarium-iron-based rare earth permanent magnet material is 70 - 99%;

[0011] The volume fraction of the (Fe,Co)2Ti phase in the high coercivity samarium-iron-based rare earth permanent magnet material is 1 - 30%.

[0012] More preferably, the volume content of the samarium-iron matrix main phase in the high coercivity samarium-iron-based rare earth permanent magnet material is 80 - 95%;

[0013] The volume content of the (Fe,Co)2Ti phase in the high coercivity samarium-iron-based rare earth permanent magnet material is 5 - 20%.

[0014] Preferably, the average grain size of the samarium-iron matrix main phase is 10 - 70 nm.

[0015] More preferably, the average grain size of the samarium-iron matrix main phase is 20 - 50 nm.

[0016] Even more preferably, the average grain size of the samarium-iron matrix main phase is 30 - 40 nm.

[0017] Preferably, the high coercivity samarium-iron-based rare earth permanent magnet material is prepared by crystallization annealing heat treatment of an amorphous rapid quenching strip.

[0018] More preferably, the amorphous rapid quenching strip is prepared by melt spinning of a master alloy ingot; the melt spinning includes: melting the master alloy ingot at 1000 - 1700 °C to obtain an alloy solution, and spraying the alloy solution onto the surface of a copper roller rotating at a high speed of 10 - 100 m / s to rapidly cool and obtain the amorphous rapid quenching strip.

[0019] More preferably, the temperature of the crystallization annealing heat treatment is 600 - 900 °C, and the time is 5 - 60 min.

[0020] Even more preferably, the temperature of the crystallization annealing heat treatment is 760 - 830 °C, and the time is 10 - 20 min.

[0021] The second object of the present invention is achieved by the following technical solutions:

[0022] A method for preparing a high coercive force samarium iron-based rare earth permanent magnetic material,

[0023] (1) According to the chemical formula Sm a Fe b Co c Ti d M e The alloy raw materials are mixed, smelted and cast to obtain a master alloy ingot; in the chemical formula, 0.5≤a≤1, 7.5≤b≤9, 0≤c≤3.0, 0.5≤d≤1.5, 0.1≤e≤2.0, and M is selected from one or more of Zr, Y, Gd, Ho and Ce;

[0024] (2) subjecting the master alloy ingot to melting and rapid quenching to obtain an amorphous rapid quenching strip;

[0025] (3) The amorphous rapid-quenching strip is subjected to a crystallization annealing heat treatment, and then rapidly cooled by water quenching to obtain a samarium-iron-based rare earth permanent magnet material with high coercivity.

[0026] Preferably, the smelting in (1) is carried out in a smelting furnace, and the operating power of the smelting furnace is 5 to 20 kw.

[0027] Preferably, the casting power in (1) is 5 to 9 kw.

[0028] Preferably, the smelting and casting in (1) comprises: placing the alloy raw material in a smelting furnace, evacuating the furnace to a vacuum degree of less than 10 -2 Pa, carry out preliminary smelting at a power of 5-10kw, then fill in high-purity argon, increase the power of the smelting furnace to 12-20kw for secondary smelting, wait for the alloy raw materials to be completely melted, reduce the power of the smelting furnace to 10-8kw for tertiary smelting, and then reduce to 5-9kw for casting to obtain the master alloy ingot.

[0029] More preferably, the temperature of the preliminary smelting is 400-900° C. and the time is 1-60 min.

[0030] More preferably, the power of the preliminary smelting is 1-10 kW.

[0031] More preferably, the secondary smelting is carried out at a temperature of 1200 to 1900° C. and for a time of 5 to 30 minutes.

[0032] More preferably, the power of the secondary smelting is 13-17 kW.

[0033] More preferably, the power of the secondary smelting is 15kw.

[0034] Further preferably, the temperature of the third melting is 1200-1800 °C, and the time is 1-5 min.

[0035] Even more preferably, the temperature of the second melting ≥ the temperature of the third melting > the temperature of the preliminary melting.

[0036] Further preferably, the power of the third melting is 9 kw.

[0037] Further preferably, the temperature of the casting is 1200-1400 °C, and the flow rate is 1-40 cm 3 / s.

[0038] Further preferably, the vacuum degree is lower than 6×10 -3 Pa.

[0039] Further preferably, the pressure of the high-purity argon is 0.04-0.1 MPa.

[0040] Even more preferably, the pressure of the high-purity argon is 0.05-0.07 MPa.

[0041] Preferably, the melt spinning in (2) includes: melting the master alloy ingot at 1000-1700 °C, spraying the alloy solution onto the surface of a copper roller rotating at a high speed of 10-100 m / s, and rapidly cooling to obtain an amorphous quenched ribbon.

[0042] Preferably, before the melt spinning in (2), the master alloy ingot is pretreated, and the pretreatment includes at least one of polishing, crushing, and grinding into powder.

[0043] Preferably, the temperature of the crystallization annealing treatment in (3) is 600-900 °C, and the time is 5-60 min.

[0044] Further preferably, the temperature of the crystallization annealing treatment in (3) is 760-830 °C, and the time is 10-20 min.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] 1. The samarium-iron-based rare earth permanent magnet material with high coercivity of the present invention includes a samarium-iron matrix main phase and a (Fe,Co)2Ti phase.

[0047] 2. By regulating the alloy composition and the quenching process, the present invention significantly affects the grain size and the microstructure morphology of the amorphous quenched ribbon.

[0048] 3. By means of the melt-spinning quenching process, the amorphous precursor inhibits the massive precipitation of α-Fe. Subsequently, short-time vacuum heat treatment is carried out, and then the key element M is added, which can further refine the grain size while achieving different degrees of improvement in the saturation magnetization intensity and coercivity of the samarium-iron-based rare earth permanent magnet material. Description of the Drawings

[0049] Figure 1 It is a transmission electron microscope photograph of the microstructure of the high-coercivity samarium-iron-based rare earth permanent magnet material in Example 1 of the present invention.

[0050] Figure 2 It is an XRD diffraction refinement fitting diagram of the high-coercivity samarium-iron-based rare earth permanent magnet material in Example 1 of the present invention.

[0051] Figure 3 It is a statistical graph of the main phase particle size distribution of the high-coercivity samarium-iron-based rare earth permanent magnet material in Example 1 of the present invention.

[0052] Figure 4 It is an element detection result diagram of the high-coercivity samarium-iron-based rare earth permanent magnet material in Example 1 of the present invention.

[0053] Figure 5 It is a transmission electron microscope photograph of the microstructure of the samarium-iron-based rare earth permanent magnet material in Comparative Example 1 of the present invention.

[0054] Figure 6 It is an element detection result diagram of the samarium-iron-based rare earth permanent magnet material in Comparative Example 1 of the present invention.

[0055] Figure 7 It is a statistical graph of the particle size distribution of the samarium-iron-based rare earth permanent magnet material in Comparative Example 1 of the present invention. Detailed Embodiments

[0056] The technical solutions of the present invention will be further described and illustrated below through specific examples and drawings. It should be understood that the specific examples described herein are only used to help understand the present invention and do not specifically limit the present invention. And the drawings used herein are only for better illustrating the content disclosed by the present invention and do not limit the protection scope.

[0057] If there is no special description, the raw materials used in the embodiments of the present invention are all common raw materials in the art, and the methods used in the embodiments are all conventional methods in the art.

[0058] Example 1

[0059] (1) Weigh the alloy raw materials according to the chemical formula Sm 0.9 Gd 0.1 Fe 8.8 Co 2.2 Ti1.

[0060] Place the alloy raw materials in a melting furnace, evacuate to a vacuum degree lower than 6×10 -3 Pa, conduct preliminary melting at a power of 5 kw, then fill with high-purity argon gas at 0.06 MPa, increase the power of the melting furnace to 15 kw for secondary melting. When the alloy raw materials are completely melted, reduce the power of the melting furnace to 9 kw and keep warm for 5 min for tertiary melting, and then reduce to 7 kw for casting to obtain the master alloy ingot.

[0061] (2) After grinding the surface of the master alloy ingot, break it into small pieces, put them into a quartz tube with a pipe orifice diameter of 1 mm, and the height of the pipe orifice from the copper wheel is 2 mm. After the copper wheel speed reaches 50 m / s, increase the melting power until the temperature reaches 1600 °C for rapid melting and quenching until all the master alloy ingots are melted; open the valve connecting the gas storage tank and the quartz tube in the furnace cavity until the pressure difference between the gas storage tank and the furnace cavity is 0.08 MPa, and spray the alloy solution onto the surface of the copper roller rotating at a high speed of 50 m / s to obtain the amorphous rapid quenching strip by rapid cooling.

[0062] (3) Place the amorphous rapid quenching strip in a sealing machine for vacuum pretreatment. After evacuating to 1×10 -5 Pa, fill with high-purity argon gas to 0.7 Pa, use a blowtorch to completely seal the quartz tube, and then conduct crystallization heat treatment using a muffle furnace. The heat treatment temperature is 800 °C, the treatment time is 10 min, and immediately adopt water quenching and rapid cooling method for cooling after the heat preservation ends to obtain the samarium-iron-based rare earth permanent magnetic material with high coercivity.

[0063] The transmission electron microscope photo and XRD diffraction refinement fitting diagram of the microstructure of the samarium-iron-based rare earth permanent magnetic material with high coercivity in this example are as shown in Figure 1 、 2 It can be seen that the microstructure of the samarium-iron-based permanent magnetic material after crystallization heat treatment is composed of the samarium-iron matrix main phase and the (Fe,Co)2Ti phase, and the volume fraction ratios of the samarium-iron matrix main phase and the (Fe,Co)2Ti phase are 93.69% and 6.31% respectively. Figure 3 is the statistical chart of the main phase particle size distribution. It can be seen that the average grain size of the main phase is small, which is 35 nm.

[0064] The element detection results of the samarium-iron-based rare earth permanent magnetic material with high coercivity in this example are as shown in Figure 4 It can be seen from Figure 4 that the doping of the key Gd element causes a small amount of precipitation of the (Fe,Co)2Ti phase in the main phase, and the grain size is significantly refined.

[0065] Example 2

[0066] (1) According to the chemical formula Sm 0.8 Gd 0.2 Fe 8.8 Co 2.2Weigh alloy raw materials;

[0067] Then obtain the master alloy ingot according to step (1) of Example 1;

[0068] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 1;

[0069] (3) Obtain the high coercivity samarium-iron-based rare earth permanent magnet material according to step (3) of Example 1.

[0070] The performance data of the high coercivity samarium-iron-based rare earth permanent magnet material in this example are shown in Table 1.

[0071] Example 3

[0072] (1) According to the chemical formula Sm 0.7 Gd 0.3 Fe 8.8 Co 2.2 Weigh alloy raw materials;

[0073] Then obtain the master alloy ingot according to step (1) of Example 1;

[0074] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 1;

[0075] (3) Obtain the high coercivity samarium-iron-based rare earth permanent magnet material according to step (3) of Example 1.

[0076] The performance data of the high coercivity samarium-iron-based rare earth permanent magnet material in this example are shown in Table 1.

[0077] Example 4

[0078] (1) According to the chemical formula Sm 0.6 Gd 0.4 Fe 8.8 Co 2.2 Weigh alloy raw materials;

[0079] Then obtain the master alloy ingot according to step (1) of Example 1;

[0080] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 1;

[0081] (3) Obtain the high coercivity samarium-iron-based rare earth permanent magnet material according to step (3) of Example 1.

[0082] The performance data of the high coercivity samarium-iron-based rare earth permanent magnet material in this example are shown in Table 1.

[0083] Example 5

[0084] (1) Obtain the master alloy ingot according to step (1) of Example 1;

[0085] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 1;

[0086] (3) Place the amorphous rapidly quenched strip in a sealing tube machine for vacuum pretreatment. After evacuating to 1×10 -5 Pa, fill it with high-purity argon gas to 0.7 Pa, use a blowtorch to completely seal the quartz tube, then perform crystallization heat treatment using a muffle furnace. The heat treatment temperature is 900 °C, the treatment time is 10 min. Immediately after the heat preservation ends, cool it by water quenching and rapid cooling to obtain a samarium-iron-based rare earth permanent magnetic material with high coercivity.

[0087] The performance data of the samarium-iron-based rare earth permanent magnetic material with high coercivity in this example are shown in Table 1.

[0088] Example 6

[0089] (1) Obtain the master alloy ingot according to step (1) of Example 2;

[0090] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 2;

[0091] (3) Place the amorphous rapidly quenched strip in a sealing tube machine for vacuum pretreatment. After evacuating to 1×10 -5 Pa, fill it with high-purity argon gas to 0.7 Pa, use a blowtorch to completely seal the quartz tube, then perform crystallization heat treatment using a muffle furnace. The heat treatment temperature is 900 °C, the treatment time is 10 min. Immediately after the heat preservation ends, cool it by water quenching and rapid cooling to obtain a samarium-iron-based rare earth permanent magnetic material with high coercivity.

[0092] The performance data of the samarium-iron-based rare earth permanent magnetic material with high coercivity in this example are shown in Table 1.

[0093] Example 7

[0094] (1) Obtain the master alloy ingot according to step (1) of Example 3;

[0095] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 3;

[0096] (3) Place the amorphous rapidly quenched strip in a sealing tube machine for vacuum pretreatment. After evacuating to 1×10 -5 Pa, fill it with high-purity argon gas to 0.7 Pa, use a blowtorch to completely seal the quartz tube, then perform crystallization heat treatment using a muffle furnace. The heat treatment temperature is 900 °C, the treatment time is 10 min. Immediately after the heat preservation ends, cool it by water quenching and rapid cooling to obtain a samarium-iron-based rare earth permanent magnetic material with high coercivity.

[0097] The performance data of the samarium-iron-based rare earth permanent magnetic material with high coercivity in this example are shown in Table 1.

[0098] Example 8

[0099] (1) Obtain the master alloy ingot according to step (1) of Example 4;

[0100] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 4;

[0101] (3) Place the amorphous rapidly quenched strip in a sealing tube machine for vacuum pretreatment. After pumping to 1×10 -5 Pa, fill with high-purity argon to 0.7 Pa, use a blowtorch to completely seal the quartz tube, then perform crystallization heat treatment using a muffle furnace. The heat treatment temperature is 900 °C, the treatment time is 10 min, and immediately after the heat preservation ends, cool it by water quenching and rapid cooling to obtain a samarium-iron-based rare earth permanent magnet material with high coercivity.

[0102] The performance data of the samarium-iron-based rare earth permanent magnet material with high coercivity in this example are shown in Table 1.

[0103] Example 9

[0104] (1) Obtain the master alloy ingot according to step (1) of Example 1;

[0105] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 1;

[0106] (3) Place the amorphous rapidly quenched strip in a sealing tube machine for vacuum pretreatment. After pumping to 1×10 -5 Pa, fill with high-purity argon to 0.7 Pa, use a blowtorch to completely seal the quartz tube, then perform crystallization heat treatment using a muffle furnace. The heat treatment temperature is 700 °C, the treatment time is 10 min, and immediately after the heat preservation ends, cool it by water quenching and rapid cooling to obtain a samarium-iron-based rare earth permanent magnet material with high coercivity.

[0107] The performance data of the samarium-iron-based rare earth permanent magnet material with high coercivity in this example are shown in Table 1.

[0108] Comparative Example 1

[0109] (1) Weigh the alloy raw materials according to the chemical formula Sm1Fe 8.8 Co 2.2 Ti1;

[0110] Then obtain the master alloy ingot according to step (1) of Example 1;

[0111] (2) Obtain the amorphous rapidly quenched strip according to step (2) of Example 1;

[0112] (3) Obtain the samarium-iron-based rare earth permanent magnet material according to step (3) of Example 1.

[0113] Figure 4 This is the transmission electron microscope test image of the samarium-iron-based rare earth permanent magnet material prepared in this comparative example; Figure 5Element detection result diagram of the samarium-iron-based rare earth permanent magnet material prepared in this comparative example; Figure 6 Particle size distribution statistical chart of the samarium-iron-based rare earth permanent magnet material prepared in this comparative example; It can be seen from Figures 4 - 6 that in the samarium-iron-based rare earth permanent magnet material without adding element M, the main phase grain size is relatively large, and the average grain size is 72 nm.

[0114] The performance of the samarium-iron-based rare earth permanent magnet material in this comparative example is shown in Table 1.

[0115] Comparative Example 2

[0116] (1) Weigh alloy raw materials according to the chemical formula Sm 0.4 Gd 0.6 Fe 8.8 Co 2.2 Ti1;

[0117] Then obtain the master alloy ingot according to step (1) of Example 1;

[0118] (2) Obtain the amorphous rapid quenching strip according to step (2) of Example 1;

[0119] (3) Obtain the samarium-iron-based rare earth permanent magnet material according to step (3) of Example 1.

[0120] The performance of the samarium-iron-based rare earth permanent magnet material in this comparative example is shown in Table 1.

[0121] Table 1. Performance data table of samarium-iron-based rare earth permanent magnet materials

[0122] Saturation magnetization (emu / g) Coercivity (Oe) Example 1 115.78 5098.03 Example 2 112.30 4632.92 Example 3 104.92 4505.24 Example 4 100.84 4313.75 Example 5 105.20 2038.30 Example 6 103.47 2021.63 Example 7 101.56 1989.93 Example 8 99.86 1721.35 Example 9 104.39 2024.62 Comparative Example 1 98.73 4304.60 Comparative Example 2 98.25 3205.12

[0123] Comparing Examples 1 to 4, it can be seen that in the samarium-iron-based rare earth permanent magnet material, as the addition amount of the key element Gd increases, the saturation magnetization intensity and coercivity show a downward trend. In Comparative Example 1, the main phase grain size in the samarium-iron-based rare earth permanent magnet material without adding Gd element is relatively large, and the coercivity is significantly inferior to that of Examples 1 to 4.

[0124] In Comparative Example 2, the content of element Gd continues to increase, resulting in the reduction of both the saturation magnetization intensity and the coercivity.

[0125] In Examples 5 to 8, the heat treatment temperature increases, and in Example 9, the heat treatment temperature drops to 700 °C. Compared with Examples 1 to 4, both the saturation magnetization intensity and the coercivity become worse.

[0126] In summary, through the melt-spinning process, the present invention enables the amorphous precursor to inhibit the massive precipitation of α-Fe, followed by short-time vacuum heat treatment and the addition of the key element M, which can significantly refine the grain size while achieving varying degrees of improvement in the saturation magnetization intensity and coercivity of the samarium-iron-based rare earth permanent magnet material.

[0127] Aspects, embodiments, and features of the present invention should be considered illustrative in all respects and not limiting of the present invention, the scope of which is defined only by the claims. Without departing from the spirit and scope of the claimed invention, those skilled in the art will appreciate other embodiments, modifications, and uses.

[0128] In the preparation method of the present invention, the order of each step is not limited to the recited order. For those of ordinary skill in the art, without creative efforts, the sequential changes of each step are also within the protection scope of the present invention. In addition, two or more steps or actions can be carried out simultaneously.

[0129] Finally, it should be noted that the specific embodiments described herein are merely illustrative of the present invention and do not limit the implementation manners of the present invention. Those skilled in the technical field to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar ways to substitute. It is not necessary and impossible to list all implementation manners here. And these obvious changes or variations derived from the essential spirit of the present invention still fall within the protection scope of the present invention. Interpreting them as any additional limitations is contrary to the spirit of the present invention.

Claims

1. A samarium-iron-based rare earth permanent magnet material with high coercivity, characterized in that, Its chemical formula is Sm a Fe b Co c Ti d M e , where 0.5 ≤ a ≤ 1, 7.5 ≤ b ≤ 9, 0 ≤ c ≤ 3.0, 0.5 ≤ d ≤ 1.5, 0.1 ≤ e ≤ 2.0, and M is selected from one or more of Zr, Y, Gd, Ho, and Ce; The high coercivity samarium-iron-based rare earth permanent magnet material comprises a samarium-iron matrix main phase and a (Fe,Co)2Ti phase.

2. The high coercivity samarium-iron-based rare earth permanent magnet material according to claim 1, wherein In the high coercivity samarium-iron-based rare earth permanent magnet material, the volume fraction of the samarium-iron matrix main phase accounts for 70-99%; the volume fraction of the (Fe,Co)2Ti phase in the high coercivity samarium-iron-based rare earth permanent magnet material accounts for 1-30%.

3. The high coercivity samarium-iron-based rare earth permanent magnet material according to claim 1, characterized in that, The average grain size of the samarium-iron matrix main phase is 10-70 nm.

4. The samarium-iron-based rare earth permanent magnet material with high coercivity according to claim 1, characterized in that, The high coercivity samarium-iron-based rare earth permanent magnet material is prepared by subjecting an amorphous rapidly quenched strip to crystallization annealing heat treatment.

5. The samarium-iron-based rare earth permanent magnet material with high coercivity according to claim 4, characterized in that, The temperature of the crystallization annealing heat treatment is 600-900 °C, and the time is 5-60 min.

6. A method for preparing a samarium-iron-based rare earth permanent magnet material with high coercivity as described in claim 1, characterized in that, The preparation method includes: (1) According to the chemical formula Sm a Fe b Co c Ti d M e Ingredient alloy raw materials, and obtain a master alloy ingot through melting and casting; in the said chemical formula, 0.5 ≤ a ≤ 1, 7.5 ≤ b ≤ 9, 0 ≤ c ≤ 3.0, 0.5 ≤ d ≤ 1.5, 0.1 ≤ e ≤ 2.0, M is selected from one or more of Zr, Y, Gd, Ho, Ce; (2) Melting and rapidly quenching the master alloy ingot by spinning to obtain an amorphous rapidly quenched strip; (3) Subjecting the amorphous rapidly quenched strip to crystallization annealing heat treatment, and then rapidly cooling by water quenching to obtain the high coercivity samarium-iron-based rare earth permanent magnet material.

7. The preparation method of the samarium-iron-based rare earth permanent magnet material with high coercivity according to claim 6, characterized in that, The melting in (1) is carried out in a melting furnace, and the working power of the melting furnace is 5-20 kw.

8. The preparation method of the samarium-iron-based rare earth permanent magnetic material with high coercivity according to claim 6, characterized in that The melting and casting in (1) include: placing alloy raw materials in a melting furnace, evacuating to a vacuum degree lower than 10 -2 Pa, initially melting at a power of 5 - 10 kw, then filling with high-purity argon gas, increasing the power of the melting furnace to 12 - 20 kw for secondary melting, waiting until the alloy raw materials are completely melted, reducing the power of the melting furnace to 10 - 8 kw for tertiary melting, and then reducing to 5 - 9 kw for casting to obtain a master alloy ingot.

9. The preparation method of the samarium-iron-based rare earth permanent magnetic material with high coercivity according to claim 6, characterized in that, The melting and rapid quenching by spinning in (2) includes: melting the master alloy ingot at 1000-1700 °C, spraying the alloy solution onto the surface of a copper roller rotating at a high speed of 10-100 m / s, and rapidly cooling to obtain an amorphous rapidly quenched strip.

10. The preparation method of the samarium-iron-based rare earth permanent magnet material with high coercivity according to claim 6, characterized in that, The temperature of the crystallization annealing heat treatment in (3) is 600-900 °C, and the time is 5-60 min.

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