Preparation method of TbSmFe magnetostrictive material and TbSmFe magnetostrictive material
By constructing a (1-x)TbFe2-xSmFe2 alloy system and combining it with a heat treatment process, TbSmFe magnetostrictive materials with high Curie temperature and large magnetostrictive strain were prepared, which solved the problem of insufficient performance of traditional materials in high-temperature environments and achieved stable operation and excellent magnetostrictive properties at high temperatures.
Patent Information
- Application Number
- CN202510582215.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-07
- Publication Date
- 2025-09-12
AI Technical Summary
Traditional rare earth-based magnetostrictive materials have a low Curie temperature, which limits their application in high-temperature environments.
By constructing a (1-x)TbFe2-xSmFe2 alloy system and combining it with a heat treatment process, TbSmFe magnetostrictive material with high Curie temperature and large magnetostrictive strain was prepared.
The material's Curie temperature was significantly increased to 725K, enabling stable operation in high-temperature environments and improving magnetostrictive performance in the temperature range from room temperature to 150°C.
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Figure CN120637068A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of magnetostrictive materials, and in particular to a preparation method and material of a TbSmFe magnetostrictive material. Background Art
[0002] Giant magnetostrictive materials have excellent properties such as large output strain, low sound velocity, high energy density, extremely fast response speed and large unit output area. They are widely used in geophysical exploration, precision machining, intelligent robots, biomedicine and other fields, and are one of the most important strategic functional materials in my country.
[0003] With the increasing demand for materials that can work stably in high-temperature environments in scenarios such as aerospace and oil and gas exploration, rare earth-based magnetostrictive materials have received widespread attention due to their excellent physical properties. However, traditional rare earth-based magnetostrictive materials often face the problem of low Curie temperature, which limits their application range under high-temperature conditions. In order to overcome this challenge, researchers are committed to improving the thermal stability and magnetostrictive properties of materials through alloying strategies. By mixing Tb and Dy with transition metals, the Curie temperature of their intermetallic compounds is significantly increased. TbFe2 and DyFe2 have good room-temperature magnetostrictive properties, but they still cannot meet the application requirements in high-temperature scenarios.
[0004] It is of great significance to develop a magnetostrictive material with higher Curie temperature and magnetostrictive properties and the ability to work stably in high temperature environments.
[0005] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the Invention
[0006] The present invention provides a method for preparing a TbSmFe magnetostrictive material and the material. By constructing a (1-x)TbFe2-xSmFe2 alloy system and combining it with a heat treatment process, a TbSmFe magnetostrictive material with a high Curie temperature and a large magnetostrictive strain is successfully developed, and the material can also work stably in a high-temperature environment.
[0007] A method for preparing a TbSmFe magnetostrictive material comprises:
[0008] Step 1: Mix the ingredients and weigh the raw materials to satisfy (1-x)TbSm2-xSmFe2, where x is (0-1).
[0009] Step 2: High vacuum arc melting. Place the prepared raw materials and titanium balls in the melting furnace and pump the cavity to a high vacuum state with an air pressure of less than 5×10 -3 pa, then fill with argon as a protective gas and start melting to obtain the sample;
[0010] Step 3: Diamond cutting: using a diamond cutting machine to cut it into discs with parallel upper and lower surfaces;
[0011] Step 4: polishing: polishing the surface of the sample after wire-cutting to a metallic luster;
[0012] Step 5: Seal the tube and place the cut and cleaned sample into a quartz tube, wrap it with molybdenum foil, and add 1g of titanium wire to absorb the residual oxygen in the tube;
[0013] Step 6, heat treatment, placing the sealed sample in a muffle furnace for heat treatment to obtain a TbSmFe magnetostrictive material with uniform structure.
[0014] In the method for preparing a TbSmFe magnetostrictive material, in step 1, the purity of the rare earth raw materials Tb and Sm is not less than 99.9%, and the purity of the transition metal Fe is not less than 99.95%. The surface oxide layer is removed before weighing. After the rare earth raw materials are removed from the kerosene, their flat surface is first polished with 800-grit sandpaper until the raw material surface is bright silver, and uneven parts are polished with a grinding wheel.
[0015] In the method for preparing the TbSmFe magnetostrictive material, in step 1, x is 0-1, and the raw materials are weighed on an analytical balance with a weighing accuracy controlled to ±0.0005 g.
[0016] In the method for preparing the TbSmFe magnetostrictive material, in step 1, the rare earth element Tb is added in excess of 5% based on the actual weighed mass to compensate for smelting loss, and the rare earth element Sm is added in excess of 10% based on the actual weighed mass to compensate for smelting loss.
[0017] In the method for preparing a TbSmFe magnetostrictive material, in step 2, the current is adjusted to 70A to start the arc, and the arc is directed to the copper plate. Before smelting the sample, the titanium ball is melted and kept in a liquid state for 1 minute to absorb residual oxygen in the cavity. The raw material is then smelted, and the current is gradually increased to melt the raw material into a spherical shape. The shape is maintained for 60 seconds, and the water cooling system is turned on. The cavity is pumped to a high vacuum state using a vacuum pump, a mechanical pump, or a diffusion pump. Each sample is smelted four times, and the alloy ingot is used to turn the sample upside down each time. The final smelted sample is button-shaped.
[0018] In the method for preparing the TbSmFe magnetostrictive material, in step 4, the polished sample is placed in acetone and anhydrous ethanol and ultrasonically cleaned for 15 minutes in sequence to clean the impurities remaining on the surface.
[0019] In the method for preparing TbSmFe magnetostrictive material, in step 5, a mechanical pump is used to pump the gas in the tube to below 1 Pa, high-purity argon gas at 3 / 4 atmospheric pressure is introduced, and the gas is pumped to below 1 Pa using a mechanical pump again. The above process is repeated three times to complete the gas washing. After the last pumping with the mechanical pump, the molecular pump is turned on to pump the gas pressure in the tube to 1×10 -3 Below pa, finally high-purity argon gas at one-third atmospheric pressure is introduced as protective gas, and the opening is sealed by a hydrogen flame.
[0020] In the method for preparing a TbSmFe magnetostrictive material, in step 6, the holding temperature of the heat treatment is 900-1200° C., the holding time is 6-168 hours, and the cooling method is furnace cooling or air cooling to obtain a uniform RT2 phase alloy sample.
[0021] A TbSmFe magnetostrictive material is prepared by the method.
[0022] In the TbSmFe magnetostrictive material, the Curie temperature of the sample with the component x=0.1 is 725K, and the magnetostriction coefficient along the magnetic field direction is 1039-1961ppm within the temperature range of 19-150°C.
[0023] Compared with existing technologies, the present invention offers the following advantages: By designing a (1-x)TbFe2-xSmFe2 system, the present invention produces a high-Curie-temperature, homogeneous alloy through arc melting and heat treatment. The heat-treated sample with the x=0.1 component exhibits a Curie temperature of 725K, significantly higher than the 653K Curie temperature of the currently commercially available magnetostrictive alloy Terfenol-D. The parallel magnetostriction of the heat-treated sample with the x=0.1 component reaches 1961 ppm at room temperature and exceeds 1000 ppm from room temperature to 150°C. The simple preparation process and excellent material properties provide an effective solution for the application of magnetostrictive materials in high-temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Various other advantages and benefits of the present invention will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are intended only to illustrate preferred embodiments and are not to be construed as limiting the present invention. It should be understood that the drawings described below are merely examples of the present invention, and that those skilled in the art will be able to derive other drawings from these drawings without inventive effort. Throughout the drawings, identical reference numerals are used to denote identical components.
[0025] In the attached figure:
[0026] Figure 1This is the magnetization intensity-temperature curve of Example 1 of the present invention;
[0027] Figure 2 1 is the magnetostriction-magnetic field intensity curve at different temperatures of Example 1 of the present invention.
[0028] The present invention will be further explained below with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION
[0029] Specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.
[0030] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the invention. The scope of protection of the present invention shall be as defined in the attached claims.
[0031] To facilitate understanding of the embodiments of the present invention, further explanation will be given below using specific embodiments as examples in conjunction with the accompanying drawings, and the accompanying drawings do not constitute a limitation on the embodiments of the present invention.
[0032] like Figures 1 to 2 As shown, the method for preparing TbSmFe magnetostrictive material includes the following steps:
[0033] Step 1: Mix the ingredients and weigh the raw materials to satisfy (1-x)TbSm2-xSmFe2, where x is (0-1).
[0034] Step 2: High vacuum arc melting. Place the prepared raw materials and titanium balls in the melting furnace and pump the cavity to a high vacuum state with an air pressure of less than 5×10 -3 pa, then fill with argon as a protective gas and start melting to obtain the sample;
[0035] Step 3: Diamond cutting: using a diamond cutting machine to cut it into discs with parallel upper and lower surfaces;
[0036] Step 4: polishing: polishing the surface of the sample after wire-cutting to a metallic luster;
[0037] Step 5: Seal the tube and place the cut and cleaned sample into a quartz tube, wrap it with molybdenum foil, and add 1g of titanium wire to absorb the residual oxygen in the tube;
[0038] Step 6, heat treatment, placing the sealed sample in a muffle furnace for heat treatment, heating from room temperature to 900°C at a rate of 100°C / h, keeping the temperature for 24h, and then cooling with the furnace to obtain TbSmFe magnetostrictive material.
[0039] In a preferred embodiment of the method for preparing a TbSmFe magnetostrictive material, in step 1, the purity of the rare earth raw materials Tb and Sm is not less than 99.9%, and the purity of the transition metal Fe is not less than 99.95%. The surface oxide layer is removed before weighing. After the rare earth raw material is removed from the kerosene, its flat surface is first polished with 800-grit sandpaper until the raw material surface is bright silver, and uneven parts are polished with a grinding wheel.
[0040] In a preferred embodiment of the method for preparing the TbSmFe magnetostrictive material, in step 1, x is 0-1, and the raw materials are weighed on an analytical balance with a weighing accuracy of ±0.0005 g.
[0041] In a preferred embodiment of the method for preparing TbSmFe magnetostrictive material, in step 1, the rare earth element Tb is added in excess of 5% of the actual weighed mass to compensate for melting loss, and the rare earth element Sm is added in excess of 10% of the actual weighed mass to compensate for melting loss.
[0042] In a preferred embodiment of the method for preparing a TbSmFe magnetostrictive material, in step 2, the current is adjusted to 70A to start the arc, and the arc is directed to the copper disk. Before smelting the sample, the titanium ball is melted and kept in a liquid state for 1 minute to absorb the residual oxygen in the cavity. The raw material is then smelted, and the current is gradually increased to melt the raw material into a spherical shape. The shape is maintained for 60 seconds, the water cooling system is turned on, and the cavity is pumped to a high vacuum state using a vacuum pump, a mechanical pump, or a diffusion pump. Each sample is smelted 4 times, and the alloy ingot is used to turn the sample upside down each time. The final smelted sample is button-shaped.
[0043] In a preferred embodiment of the method for preparing the TbSmFe magnetostrictive material, in step 4, the polished sample is ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes in sequence to clean any impurities remaining on the surface.
[0044] In a preferred embodiment of the method for preparing TbSmFe magnetostrictive material, in step 5, a mechanical pump is used to pump the gas in the tube to below 1 Pa, high-purity argon gas at 3 / 4 atmospheric pressure is introduced, and then the mechanical pump is used to pump the gas to below 1 Pa. The above process is repeated three times to complete the gas washing. After the last pumping with the mechanical pump, the molecular pump is turned on to pump the gas pressure in the tube to 1×10 -3 Below pa, finally high-purity argon gas at one-third atmospheric pressure is introduced as protective gas, and the opening is sealed by a hydrogen flame.
[0045] In a preferred embodiment of the method for preparing the TbSmFe magnetostrictive material, in step 6, the temperature is raised from room temperature to 900° C. at a rate of 100° C. / h, kept at this temperature for 24 hours, and then cooled in the furnace.
[0046] A TbSmFe magnetostrictive material is prepared by the method.
[0047] In a preferred embodiment of the TbSmFe magnetostrictive material, the Curie temperature of the heat-treated sample with the x=0.1 component is 725K, which is significantly higher than the Curie temperature (653K) of the commercial magnetostrictive material Terfenol-D. In the temperature range of 19-150°C, the magnetostriction coefficient along the magnetic field direction is 1039-1961ppm, the parallel magnetostriction at room temperature reaches 1961ppm, and the parallel magnetostriction from room temperature to 150°C is greater than 1000pmm.
[0048] In one embodiment, the method includes:
[0049] Step 1, ingredients, use a high-precision analytical balance to accurately weigh the required various high-purity metal elements, including rare earth elements terbium (Tb) and samarium (Sm) with a purity of not less than 99.9%, and transition metal iron (Fe) with a purity of up to 99.95%.
[0050] Optionally, in step 1, the raw materials need to be strictly cleaned before weighing to remove oxides or other impurities that may exist on the surface. For the rare earth elements extracted from kerosene, first use 800-grit sandpaper to polish their flat surface, and use a grinder to polish the uneven parts until the surface of the raw material is bright silver.
[0051] Preferably, in step 1, seven different component ratios are selected, namely the (1-x)TbFe2-xSmFe2 system (x=0-1), and the total mass of each sample is precisely controlled to be 6.0000g on an analytical balance, with an allowable error range of no more than ±0.0005g.
[0052] Preferably, in step 1, the rare earth element Tb is added in excess of 5% based on the actual weighed mass to compensate for smelting loss, and the rare earth element Sm is added in excess of 10% based on the actual weighed mass to compensate for smelting loss.
[0053] Step 2: Arc melting. Place the prepared raw materials and titanium balls in the melting furnace, turn on the water cooling system, and use a vacuum pump (mechanical pump and diffusion pump) to pump the cavity to a high vacuum state (pressure less than 5×10 -3 pa), then fill in argon as a protective gas and start smelting.
[0054] Optionally, in step 2, the current is adjusted to about 70A to start the arc, and the arc is directed to the copper plate. Before melting the sample, the titanium ball needs to be melted and kept in liquid state for about 1 minute to absorb the residual oxygen in the cavity, and then the raw material is melted. The current is gradually increased to melt the raw material into a ball, and it is kept for about 60 seconds for sufficient mixing.
[0055] Preferably, in step 2, each sample needs to undergo four melting processes, and the sample needs to be turned over after each melting to ensure that the components are evenly distributed, and finally a button-shaped sample is formed.
[0056] Step 3: Diamond cutting: Use a low-speed diamond cutting machine to cut it into discs with parallel upper and lower surfaces to meet the requirements of subsequent testing and application.
[0057] Step 4: Polishing: Use 800-grit sandpaper to polish the sample surface with oil stains and oxide layer after wire-cutting to obtain metallic luster.
[0058] Optionally, in step 4, the polished sample is immersed in acetone and anhydrous ethanol for ultrasonic cleaning for 15 minutes each to ensure that the surface is clean and free of contamination.
[0059] Step 5: Seal the tube, place the cut and cleaned sample into a quartz tube, wrap it with molybdenum foil, and add about 1g of high-purity titanium wire to absorb the residual oxygen in the tube.
[0060] Optionally, in step 5, use a mechanical pump to pump the gas in the tube to below 1 Pa, introduce high-purity argon gas at three-quarters atmospheric pressure, and then use a mechanical pump to pump the gas to below 1 Pa. Repeat the above process three times to complete the gas washing. After the last round of pumping with the mechanical pump, turn on the molecular pump to pump the gas pressure in the tube to 1×10 -3 Below pa, and finally high-purity argon gas at one-third atmospheric pressure is introduced as protective gas.
[0061] Preferably, in step 5, after vacuuming and introducing protective gas, the opening is sealed by passing a hydrogen flame.
[0062] Step 6: Heat treatment: Place the sealed sample together with the quartz tube into a muffle furnace for heat treatment.
[0063] Preferably, in step 6, the temperature is raised from room temperature to 900° C. at a rate of 100° C. / h, kept at this temperature for 24 hours, and then cooled in the furnace.
[0064] In one embodiment, a TbSmFe material with excellent high-temperature magnetostrictive properties and a preparation method thereof are provided. The TbSmFe material is prepared by heat-treating a (1-x)TbFe2-xSmFe2 alloy. The heat-treated sample exhibits a Curie temperature significantly higher than the Curie temperature (653K) of the commercial magnetostrictive material Terfenol-D. The material also exhibits excellent high-temperature magnetostrictive properties, with a parallel magnetostriction of 1961 ppm at room temperature and greater than 1000 ppm from room temperature to 150°C. The magnetostrictive material provided by the present invention has a simple preparation process and is amenable to industrial production. It has broad application prospects in aerospace, oil drilling, and other fields.
[0065] Example
[0066] The present invention is further described below through specific examples, but these examples are merely exemplary and do not constitute any limitation to the scope of protection of the present invention.
[0067] Example 1
[0068] Preparation of a heat-treated magnetostrictive material having a composition of (1-x)TbFe2-xSmFe2 (x=0.1) specifically comprises the following steps:
[0069] Step 1:
[0070] The ingredients are prepared using a high-precision analytical balance to accurately weigh the various high-purity metal elements required, including rare earth elements terbium (Tb) and samarium (Sm) with a purity of not less than 99.9%, and transition metal iron (Fe) with a purity of up to 99.95%. The raw materials are strictly cleaned before weighing to remove any oxides or other impurities that may be present on the surface. For the rare earth elements extracted from kerosene, their smooth surfaces are first polished with 800-mesh sandpaper, and any uneven areas are polished with a grinder until the surface of the raw material is bright silver. Seven different component ratios are selected, namely the (1-x)TbFe2-xSmFe2 system (x=0-1), and the total mass of each sample is precisely controlled on an analytical balance to be 6.0000g, with an allowable error range of no more than ±0.0005g. The rare earth element Tb is weighed at an excess of 5% based on the actual weighed mass to compensate for smelting losses, and the rare earth element Sm is weighed at an excess of 10% based on the actual weighed mass to compensate for smelting losses.
[0071] Step 2:
[0072] Arc melting: Place the prepared raw materials and titanium balls in the melting furnace, turn on the water cooling system, and use a vacuum pump (mechanical pump and diffusion pump) to pump the cavity to a high vacuum state (pressure less than 5×10 -3 pa), then fill with argon as a protective gas and start melting; adjust the current to about 70A to start the arc, and lead the arc to the copper plate. Before melting the sample, it is necessary to melt the titanium ball and keep it in liquid state for about 1 minute to absorb the residual oxygen in the cavity, and then melt the raw material. Gradually increase the current to melt the raw material into a ball, and keep it for about 60 seconds to fully mix it; each sample needs to go through four melting processes, and the sample needs to be turned over after each melting to ensure that the components are evenly distributed, and finally a button-shaped sample is formed.
[0073] Step 3:
[0074] Diamond cutting: Use a low-speed diamond cutting machine to cut it into discs with parallel upper and lower surfaces to meet the requirements of subsequent testing and application.
[0075] Step 4:
[0076] Polishing: Use 800-grit sandpaper to polish the sample surface with oil stains and oxide layer after diamond cutting until it has a metallic luster; immerse the polished sample in acetone and anhydrous ethanol for ultrasonic cleaning for 15 minutes each to ensure that the surface is clean and free of pollution.
[0077] Step 5:
[0078] Seal the tube, place the cut and cleaned sample into a quartz tube, wrap it with molybdenum foil, and add about 1g of high-purity titanium wire to absorb the residual oxygen in the tube; use a mechanical pump to pump the gas in the tube to below 1Pa, introduce high-purity argon gas at three-quarters of an atmosphere, and then use a mechanical pump to pump the gas to below 1Pa. Repeat the above process three times to complete the gas washing. After the last pumping with the mechanical pump, turn on the molecular pump and pump the gas pressure in the tube to 1×10 -3 Below pa, finally high-purity argon gas at one-third atmospheric pressure is introduced as protective gas; after vacuuming and introducing protective gas, the opening is sealed by a hydrogen flame.
[0079] Step 6:
[0080] Heat treatment: The sealed sample was placed in a muffle furnace for heat treatment, heating from room temperature to 900°C at a rate of 100°C / h, keeping the temperature for 24h, and cooling with the furnace.
[0081] Performance Testing
[0082] (1) Magnetization intensity-temperature curve
[0083] The heat-treated samples were polished with 800-grit sandpaper to remove any oil stains and oxide layers from the diamond-cut samples until they had a metallic luster. The polished samples were ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each to ensure a clean surface. The cleaned samples were cut into small particles of 30 to 50 mg using clean pliers. The MT curves of the samples at 300 K to 800 K were measured using a Dynacool VSM magnetometer developed and produced by Quantum Design, USA, and a magnetic field of 100 Oe was applied. The test results are shown in Figure 2. Figure 1 shown.
[0084] (2) Magnetostriction test
[0085] The semicircular sample before and after heat treatment was tested. The sample surface should be as flat as possible before testing. The sample was first polished. The sample surface was polished clean with 400 mesh and 800 mesh sandpaper in turn. The strain gauge was pasted on the sample surface with 502 adhesive. Note that the pasting direction is parallel to the magnetic field direction and at a 45° angle to the polished scratch. The magnetostrictive properties of the sample were tested at room temperature, 50℃, 75℃, 100℃, 125℃, and 150℃. The external magnetic field change value was set to -20000Oe~20000Oe, and the measurement step was 400Oe. The test results are as follows: Figure 2 shown.
[0086] according to Figure 2 , the parallel magnetostriction coefficient of Example 1 under 20kOe conditions is shown in Table 1.
[0087] Table 1
[0088] Temperature / ℃ Example 1 Parallel magnetostriction / ppm 19 1961.4 50 1637.4 75 1539.8 100 1359.6 125 1259.8 150 1039.3
[0089] Example 2
[0090] A (1-x)TbFe2-xSmFe2 alloy was prepared in a manner similar to Example 1, except that in step 1, the ingredients were prepared according to an atomic ratio of x=0.2.
[0091] After the preparation is completed, the tube sealing and heat treatment steps are performed in the same manner as in Example 1.
[0092] The TbSmFe magnetostrictive material finally obtained had a parallel magnetostriction coefficient of Example 2 under 20 kOe conditions as shown in Table 2.
[0093] Table 2
[0094] Temperature / ℃ Example 2 Parallel magnetostriction / ppm 25 1040.5 50 990.8 75 910.7 100 526.9 125 447.8 150 396.0
[0095] Example 3
[0096] A (1-x)TbFe2-xSmFe2 alloy was prepared in a manner similar to Example 1, except that in step 1, the ingredients were prepared according to an atomic ratio of x=0.25.
[0097] After the preparation is completed, the tube sealing and heat treatment steps are performed in the same manner as in Example 1.
[0098] The TbSmFe magnetostrictive material finally obtained had a parallel magnetostriction coefficient of Example 3 under 20 kOe conditions as shown in Table 3.
[0099] Table 3
[0100] Temperature / ℃ Example 3 Parallel magnetostriction / ppm 25 1262.9 50 1222.5 75 951.6 100 475.7 125 438.4 150 379.6
[0101] analyze:
[0102] The magnetization intensity-temperature curve shows that Example 1 has the highest Curie temperature and the best high-temperature magnetostrictive performance among the examples. The Curie temperature of Example 1 is 725K, which is significantly higher than the Curie temperature (653K) of the commercial magnetostrictive material Terfenol-D, which is beneficial to improving the high-temperature stability of the material's magnetic properties.
[0103] The magnetostriction test results show that the sample of Example 1 has a parallel magnetostriction of 1961 ppm at room temperature under a magnetic field of 20 kOe, and a parallel magnetostriction greater than 1000 pmm at 19°C to 150°C.
[0104] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments and application fields. The above-mentioned specific embodiments are merely illustrative and instructive, and are not restrictive. A person skilled in the art, guided by this specification and without departing from the scope of protection of the claims of the present invention, may also devise various forms, all of which fall within the scope of protection of the present invention.
Claims
1. A method for preparing a TbSmFe magnetostrictive material, characterized in that: The steps include: Step 1, ingredients, weigh the raw materials to meet (1-x)TbSm2-xSmFe2, x is 0-1; Step 2: High vacuum arc melting. Place the prepared raw materials and titanium balls in the melting furnace and pump the cavity to a high vacuum state with an air pressure of less than 5×10 -3 pa, then fill with argon as a protective gas and start melting to obtain the sample; Step 3: Diamond cutting: using a diamond cutting machine to cut it into discs with parallel upper and lower surfaces; Step 4: polishing: polishing the surface of the sample after wire-cutting to a metallic luster; Step 5: Seal the tube and place the cut and cleaned sample into a quartz tube, wrap it with molybdenum foil, and add 1g of titanium wire to absorb the residual oxygen in the tube; Step 6: heat treatment, placing the sealed sample into a muffle furnace for heat treatment.
2. The method for preparing a TbSmFe magnetostrictive material according to claim 1, wherein: Preferably, in step 1, the purity of the rare earth raw materials Tb and Sm is not less than 99.9%, and the purity of the transition metal Fe is not less than 99.95%. The oxide layer on the surface is removed before weighing. After the rare earth raw materials are taken out of kerosene, their flat surface is first polished with 800-grit sandpaper until the surface of the raw material is bright silver, and the uneven parts are polished with a grinding wheel.
3. The method for preparing a TbSmFe magnetostrictive material according to claim 1, wherein: In step 1, x is 0-1, and the raw materials are weighed on an analytical balance with a weighing accuracy of ±0.0005 g.
4. The method for preparing a TbSmFe magnetostrictive material according to claim 1, wherein: In step 1, the rare earth element Tb is added in excess of 5% based on the actual weighed mass to compensate for smelting loss, and the rare earth element Sm is added in excess of 10% based on the actual weighed mass to compensate for smelting loss.
5. The method for preparing a TbSmFe magnetostrictive material according to claim 1, wherein: In step 2, adjust the current to 70A to start the arc, and lead the arc to the copper plate. Before melting the sample, melt the titanium ball and keep it in liquid state for 1 minute to absorb the residual oxygen in the cavity, and then melt the raw material. Gradually increase the current to melt the raw material into a spherical shape, hold for 60 seconds, turn on the water cooling system, and use a vacuum pump, mechanical pump or diffusion pump to pump the cavity to a high vacuum state. Each sample is melted 4 times, and the alloy ingot is used to turn the sample up and down each time. The final melted sample is button-shaped.
6. The method for preparing a TbSmFe magnetostrictive material according to claim 1, wherein: In step 4, the polished sample was ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes in sequence to clean the impurities remaining on the surface.
7. The method for preparing a TbSmFe magnetostrictive material according to claim 1, wherein: In step 5, use a mechanical pump to pump the gas in the tube to below 1 Pa, introduce high-purity argon gas at three-quarters atmospheric pressure, and then use a mechanical pump to pump the gas to below 1 Pa. Repeat the above process three times to complete the gas washing. After the last pumping with the mechanical pump, turn on the molecular pump to pump the gas pressure in the tube to 1×10 -3 Below pa, finally high-purity argon gas at one-third atmospheric pressure is introduced as protective gas, and the opening is sealed by a hydrogen flame.
8. The method for preparing a TbSmFe magnetostrictive material according to claim 1, wherein: In step 6, the holding temperature of the heat treatment is 900-1200° C., the holding time is 6-168 hours, and the cooling method is furnace cooling or air cooling to obtain a uniform RT2 phase alloy sample.
9. A TbSmFe magnetostrictive material, characterized in that It is prepared by the method according to any one of claims 1 to 8.
10. The TbSmFe magnetostrictive material according to claim 9, characterized in that: The Curie temperature of the sample with x=0.1 component is 725K, and the magnetostriction coefficient along the magnetic field direction is 1039-1961ppm in the temperature range of 19-150°C.