CN104947194B - A kind of magnetostriction materials and preparation method thereof - Google Patents

Abstract

The invention provides a magnetostrictive material and a preparation method thereof. The composition of the magnetostrictive material is (Fe _1‑x Ga _x ) _100‑y RE _y , wherein 0.17≤x≤0.19, 0.01≤y≤0.2, and RE is selected from Tb, La, Sm, Dy, Lu, Ho, Er and one or more of Tm. After smelting Fe, Ga and RE prepared according to the composition requirements into master alloy ingots and making master alloy rods, the master alloy rods and <100> oriented FeGa single crystal seeds were placed in the directional solidification equipment, and the orientation After the solidification equipment is evacuated and filled with protective gas, it is heated to completely melt the master alloy rod and the upper part of the FeGa single crystal seed crystal, and the molten material is pulled along the lower part of the FeGa single crystal seed crystal into the cooling liquid for directional solidification, and The temperature gradient is controlled to be 1×10 ⁵ -9×10 ⁵ K/m, and the growth rate is 1000-20000 mm/h. The magnetostrictive material prepared by this method is a <100> oriented single crystal material, the rare earth elements are completely dissolved in the FeGa matrix, the saturation magnetic field is only 100-500Oe, the magnetostriction coefficient is as high as 300-1500ppm, and the comprehensive usability is good. , the application prospect is broad.

Description

A kind of magnetostrictive material and preparation method thereof

technical field

The invention relates to a magnetic material, in particular to a magnetostrictive material and a preparation method thereof.

Background technique

As an important class of ferromagnetic functional materials, magnetostrictive materials will reversibly change their geometric dimensions in all directions with changes in the magnetization state. This reversible deformation induced by a magnetic field is called magnetostriction. Since Joule proposed the magnetostrictive effect in 1842, magnetostrictive materials have been widely used in aviation, navigation, robotics, new energy, biomedicine and many other fields, playing an important role in the national economy and industrial production. FeGa alloy, as the latest generation of magnetostrictive material, has attracted widespread attention due to its low saturation magnetic field, good mechanical properties, and large magnetostriction. It has become a strategic new material in the 21st century.

Although the comprehensive performance of FeGa alloy is good, the saturation magnetostriction coefficient of traditional FeGa binary alloy is only 1/5 of that of Terfenol-D alloy. The substrate has a larger magnetostrictive coefficient, which becomes an inevitable choice to further improve the magnetostrictive performance of the FeGa substrate. At present, research on FeGa alloys at home and abroad is mainly focused on improving the magnetostrictive properties and optimizing the material preparation process.

The Chinese patent with publication number CN101086912A discloses a FeGa-RE system magnetostrictive material and its manufacturing process. The magnetostrictive material is polycrystalline. Its main components are Fe, Ga and RE, wherein one or more of La, Ce, Pr, Nd, Tb and Dy is added, and the content is 0.01-20at%. The manufacturing process of the magnetostrictive material includes casting the alloy after refining the raw material into the required round rod, and using the high temperature gradient rapid solidification method or the pulling method or the Bridgman method on the alloy rod to perform crystal directional growth, and finally obtain <100 > and <110> orientation magnetostrictive materials. However, the magnetostriction coefficient of this material is only about 300ppm, and the magnetostrictive performance of the material prepared by this method has not been significantly improved. The reason may be that the rare earth atoms are precipitated and pinned at the grain boundary in the form of a second phase No solid solution into the FeGa matrix.

The Chinese patent with the publication number CN103556045A discloses a novel magnetostrictive material designed based on the principle of FeGa- _RFe2 magnetocrystalline anisotropy compensation and its preparation method. The composition of the magnetostrictive polycrystalline material is (Fe _100-X Ga _X ) _Y (RFe ₂ ) _Z , where 10≤X≤40, Y and Z adjust the ratio of compensation components in the pseudo-binary system Y:Z=1～20, RFe ₂ is TbFe ₂ , SmFe ₂ , DyFe ₂ , One or more of HoFe ₂ , ErFe ₂ , TmFe ₂ . This patent adds rare earth elements such as Tb and Sm to the FeGa alloy, and uses a vacuum spinning process to prepare <100>-oriented single-phase uniform polycrystalline strips. However, the thickness of polycrystalline strips prepared by the vacuum stripping process is only tens of microns, and the low-field (<500Oe) magnetostrictive properties of the strip samples are extremely poor (<50ppm) due to the special shape anisotropy, which cannot meet Magnetostrictive devices such as high-power transducers require the use of low-field high-performance three-dimensional crystal materials.

Contents of the invention

The invention provides a magnetostrictive material, which is a <100>-oriented single crystal material, and the rare earth elements in the material are completely dissolved into the FeGa matrix, so that not only the magnetostrictive coefficient is obviously improved, but also the saturation magnetic field is relatively low, comprehensively Good usability.

The invention also provides a preparation method of the magnetostrictive material, which has simple operation, easy process control, and can produce the magnetostrictive material with good magnetostrictive performance and comprehensive usability.

The invention provides a magnetostrictive material whose composition is (Fe _1-x Ga _x ) _100-y RE _y , wherein 0.17≤x≤0.19, 0.01≤y≤0.2, and RE is selected from Tb, La, Sm, Dy , one or more of Lu, Ho, Er and Tm.

Further, the composition of the magnetostrictive material is (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 , (Fe _0.83 Ga _0.17 ) _99.95 Sm _0.05 , (Fe _0.83 Ga _0.17 ) _99.95 Dy _0.05 , (Fe _0.83 Ga _0.17 ) _99.95 Ho _0.05 , (Fe _0.83 GA _0.17 ) _99.95 ER _0.05 , (Fe _0.83 GA _0.17 ) _99.95 TM _0.05 , (Fe _0.81 GA _0.19 ) _99.95 TB _0.05 , (Fe _0.81 GA _0.19 ) _99.95 SM _0.05 , (Fe _0.81 GA _0.19 ) _99.95 DY _0.05 , (Fe _0.81 GA _0.19 ) _99.95 HO _0.05 , (Fe _0.81 GA _0.19 ) _99.95 ER _0.05 , (Fe _0.81 GA _0.19 ) _99.95 TM _0.05 , (Fe _0.83 GA _0.17 ) _99.97 Lu _0.03 , (Fe _0.81 GA _0.19 ) _99.96 DY _0.04 , (Fe _0.82 Ga _0.18 ) _99.98 Sm _0.02 , (Fe _0.81 Ga _0.19 ) _99.9 Tm _0.1 , (Fe _0.81 Ga _0.19 ) _99.8 La _0.2 , (Fe _0.82 Ga _0.18 ) _99.8 ( _HoEr ) Ga _0.2 , ( _HoEr ) 0.2 _99.84 (SmTm) _0.16 , (Fe _0.82 Ga _0.18 ) _99.85 (HoErTm) _0.15 or (Fe _0.81 Ga _0.19 ) _99.85 (TbDyHo) _0.15 .

Further, the magnetostrictive material is a <100> oriented single crystal material. In particular, the magnetostrictive material has a (200) diffraction peak at 2θ of 27° to 28°, and a (400) diffraction peak at 2θ of 56° to 57°; in addition, the magnetostrictive The diffraction spots of different crystal face groups of the material are four-fold symmetric.

Further, in the magnetostrictive material, RE is completely dissolved in the FeGa matrix. The present invention is not strictly limited to the complete solid solution, which may also include the situation of substantially complete solid solution. Specifically, it can be proved that RE is completely dissolved in the FeGa matrix by the appearance of no or substantially no RE element precipitates on the BSE image.

Further, there are multiple dislocation lines in the magnetostrictive material. In particular, at least two dislocation lines in the plurality of dislocation lines intersect each other; in particular, the plurality of dislocation lines intersect each other at one place to form radial lines radiating from the place to the surroundings. The length of the dislocation line may be 30-150 nm.

Further, the saturation magnetic field of the magnetostrictive material is 100-500 Oe, for example, 300-500 Oe, preferably 300-400 Oe, more preferably 300-350 Oe.

Further, the saturation magnetostriction coefficient of the magnetostrictive material is 300-1500 ppm, preferably 450-1500 ppm, more preferably 650-1500 ppm, still more preferably 1000-1500 ppm.

Further, the magnetostrictive material is a rod-shaped material with a diameter of 1-10 mm and a length of 1-20 mm, preferably a diameter of 5-10 mm and a length of 10-20 mm.

The present invention also provides a method for preparing any one of the magnetostrictive materials described above, comprising the steps of:

1) Prepare Fe, Ga and RE raw materials according to the composition requirements of magnetostrictive materials;

2) Melting the equipped Fe, Ga and RE raw materials into master alloy ingots;

3) melting the master alloy ingot, and making a master alloy rod by vacuum suction casting;

4) Place the master alloy rod and <100> oriented FeGa single crystal seed crystal in the directional solidification equipment, and immerse the lower part of the FeGa single crystal seed crystal in the cooling liquid, vacuumize the directional solidification equipment and fill it with protective gas , heating to completely melt the master alloy rod and melt the upper part of the FeGa single crystal seed crystal, draw the molten material along the lower part of the FeGa single crystal seed crystal into the cooling liquid for directional solidification, and control the temperature gradient of the directional solidification to be 1 ×10 ⁵ ~9×10 ⁵ K/m, the growth rate is 1000~20000mm/h, and the magnetostrictive material is produced.

In the present invention, directional solidification refers to the establishment of a temperature gradient (G) in a specific direction in the solidified metal (that is, unmelted metal) and the unsolidified metal melt, so that the melt solidifies along the direction opposite to the heat flow. Casting process; growth rate refers to the speed at which the melt is drawn into the cooling fluid. The specific rare earth elements selected in the present invention have large size and large magnetocrystalline anisotropy, and at the same time, directional solidification under the above-mentioned specific temperature gradient and growth rate is conducive to realizing complete solid solution and magnetostriction of rare earth elements in the FeGa matrix The single crystal orientation of the material. Furthermore, the temperature gradient is preferably 1×10 ⁵ -5×10 ⁵ K/m; the growth rate (V) is preferably 1000-10000 mm/h, more preferably 2000-8000 mm/h.

The present invention adopts the <100> orientation FeGa single crystal seed crystal as the seed crystal during directional solidification, and makes it into a partially molten state when using the seed crystal; specifically, the upper part of the seed crystal is melted by controlling heating and cooling, The lower part is solidified, so that the solid-liquid interface advances along the lower part of the seed crystal during the solid-liquid phase transition during directional solidification, so that the dominant orientation of the seed crystal is preserved, so that the newly formed crystals are stacked along the lattice of the seed crystal, and more It is easy to grow single crystal; in addition, the solid-liquid interface is flattened from concave through a faster growth rate (above 1000mm/h), and a higher temperature gradient (above 1×10 ⁵ K/m) inhibits nucleation, which eventually leads to The single crystal grows, so as to realize the complete solid solution of rare earth elements in the FeGa matrix and the <100> single crystal orientation of the magnetostrictive material.

The purity of the raw materials Fe, Ga and RE selected in the present invention are all greater than 99.99wt%.

In step 4) of the present invention, evacuating the directional solidification equipment and filling the protective gas includes implementing the following operations at least once:

Vacuum the directional solidification equipment to 1.0×10 ^-3 ~ 5.0×10 ^-3 Pa and then fill it with protective gas, and stop inflating after the vacuum degree in the directional solidification equipment rises to 1.0×10 ^-1 ~ 5×10 ^-1 Pa .

Preferably, the above operation is carried out three to four times.

Further, in step 4) of the present invention, the master alloy rod and the upper part of the FeGa single crystal seed crystal are placed inside the hollow graphite heating body, and the graphite heating body is heated by an induction coil to completely melt the master alloy rod and The upper part of the FeGa single crystal seed crystal is melted.

The above-mentioned heating method heats the graphite heating body to a specified temperature through the induction coil arranged outside the graphite heating body, and then releases heat to the material arranged inside it through the heat radiation of the graphite heating body, thereby realizing heating of the material. This heating method is easy to heat the material evenly, and can achieve greater heat, smaller radial temperature gradient, etc., which is beneficial to the single crystal orientation of the material.

Further, in step 4) of the present invention, the heating includes implementing the following operations at least once:

Heat the graphite heating body to 1550-1700°C at a heating rate of 30-40°C/min, keep the temperature for 5-15 minutes after the master alloy rod and the upper part of the FeGa single crystal seed crystal are melted, and then lower the temperature at a cooling rate of 20-30°C/min Cool the graphite heating body to 1450-1550°C and keep it warm for 3-8 minutes, then heat the graphite heating body to 1550-1700°C at a heating rate of 30-40°C/min and keep it warm for 5-15 minutes.

In the present invention, the temperature of the material exceeds its melting point by 50-200°C by heating, and heating in the above-mentioned specific way is not only conducive to the full melting of the material, but also to the passivation and failure of heterogeneous nucleation in the melt , thereby reducing heterogeneous nucleation in the melt and favoring single-crystal orientation of the material. Preferably, the above operation is carried out three to four times.

In addition, in step 4), the lower part of the FeGa single crystal seed crystal is immersed in the cooling liquid and the lower end contacts the water-cooled metal piece, and the cooling liquid is a Ga-In alloy.

That is to say, the present invention can realize the partially molten state of the seed crystal by heating the upper part of the FeGa single crystal seed crystal and cooling the lower part of the FeGa single crystal seed crystal. In particular, during directional solidification, a combination of Ga-In alloy (liquid metal cooling liquid) and water-cooled metal parts is used for cooling, in which Ga-In alloy is used to cool the side of the material, and water-cooled metal parts are used to cool the material. The lower end of the shaft is cooled, which is easy to achieve a large temperature gradient and achieve better axial cooling effect. Water-cooled metal parts refer to metal parts that use water as a cooling medium for cooling, and there are no strict restrictions on the structure and material of the metal parts, such as water-cooled copper fixtures.

Further, step 2) includes:

Put the equipped Fe, Ga and RE raw materials in the smelting equipment, vacuumize the smelting equipment to 5.0×10 ^-2 ~5.0×10 ^-3 Pa, then fill the protective gas, and wait until the vacuum degree in the smelting equipment rises to 1.0× 10 ^-1 ~ 5.0×10 ^-1 Pa, stop the inflation, carry out the above operation at least once, melt the raw material more than once under the condition of melting current of 100 ~ 150A, control the time of each melting for 3 ~ 5 minutes, and make Master alloy ingot.

Preferably, the raw material is smelted three to five times under the above conditions.

Further, step 3) includes:

Place the master alloy ingot in the smelting equipment, vacuumize the smelting equipment to 1.0×10 ^-3 ~ 5.0×10 ^{- 3} Pa, and then fill the protective gas until the vacuum degree in the smelting equipment rises to 1.0×10 ^- After ¹ to 5.0×10 ^-1 Pa, the inflation is stopped, and the master alloy ingot is melted into an alloy liquid under the condition of a melting current of 100 to 300A, and the alloy liquid is suction-cast into a mold to make a master alloy rod.

In the specific solution of the present invention, the smelting equipment can be conventional equipment in the field, such as a vacuum non-consumable arc melting furnace; the protective gas can be argon with a purity of 99.99% or more.

Implementation of the present invention has at least the following advantages:

1. The present invention realizes rare earth elements by adding a small amount of rare earth elements with large size and large magnetocrystalline anisotropy in the FeGa matrix, and at the same time combining a directional solidification process with a higher temperature gradient and a faster growth rate. Complete solid solution in FeGa matrix and <100> single crystal orientation of magnetostrictive materials.

2. The preparation method of the present invention is simple in operation, easy to control the process, less in the addition of rare earth elements, and short in the preparation cycle. In particular, the specific heating method is conducive to the full melting of the material and the passivation and failure of heterogeneous nucleation in the melt. The cooling method is easy to obtain a large temperature gradient, and the cooling effect is good. The magnetostrictive performance and comprehensive usability of the prepared magnetostrictive material are good, and the application range is wide.

3. The magnetostrictive material prepared by the preparation method of the present invention is a <100> oriented single crystal material, and the rare earth elements in the material are completely dissolved in the FeGa matrix, the saturation magnetic field is only 100-500Oe, and the magnetostriction coefficient is as high as 300 ~1500ppm, good comprehensive usability and broad application prospects.

Description of drawings

Fig. 1 is the BSE image of the master alloy ingot prepared in Example 1 of the present invention;

Fig. 2 is the XRD spectrum of the master alloy rod prepared in Example 1 of the present invention;

Fig. 3 is the BSE image of the magnetostrictive material prepared in Example 1 of the present invention;

Fig. 4 is the synchrotron radiation XRD pattern and the Laue diffraction pattern of the magnetostrictive material prepared in Example 1 of the present invention.

Fig. 5 is a TEM image of the Fe ₈₃ Ga ₁₇ single crystal seed used in Example 1 of the present invention;

Fig. 6 is the TEM image of the magnetostrictive material prepared in Example 1 of the present invention;

Fig. 7 is the magnetostriction curve of the Fe ₈₃ Ga ₁₇ single crystal seed crystal and the prepared magnetostrictive material used in Example 1 of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and embodiments of the present invention. Obviously, the described embodiments are the Some, but not all, embodiments are invented. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Preparation of Example 1 (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05

A method for preparing a magnetostrictive material whose composition is (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 comprises the following steps:

1. Ingredients

The purity of the selected raw materials Fe, Ga and Tb (RE raw materials) is greater than 99.99wt%, and in order to prevent the burning of elements during the smelting process, when the Fe, Ga and Tb raw materials are prepared according to the above composition, the burning loss of about 1wt% Add Ga and Tb respectively. Specifically, 27.72g of Fe, 7.158g of Ga and 0.048g of Tb were weighed and set aside.

2. Preparation of master alloy ingot

Put the above-mentioned raw materials Fe, Ga and RE into the crucible of the vacuum non-consumable arc melting furnace. When placing, put the metal elements that are easy to burn at the bottom of the crucible, and the metal elements that are not easy to burn at the top of the crucible .

After the vacuum non-consumable arc melting furnace is evacuated to 4.0×10 ^-3 Pa, high-purity argon gas is filled into the furnace body. The volume percentage (purity) of argon gas is above 99.99%. After the vacuum degree rises to 1.0×10 ^-1 Pa, stop inflating. After repeating this step three times, set the melting current to 150A to melt the raw materials. Control the time of each melting to about 4 minutes. Repeat the melting four times to produce Obtain master alloy ingot, this master alloy ingot is carried out electron probe test, its backscattered electron (BSE) image as shown in Figure 1; Known from Fig. 1, Tb element in the master alloy ingot material under as-cast state is The form of the second phase is widely distributed at the grain boundary of FeGa matrix.

3. Preparation of master alloy rods

Place the master alloy ingot prepared above in a vacuum non-consumable arc melting furnace, and after the vacuum non-consumable arc melting furnace is evacuated to 3.0×10 ^-3 Pa, fill the furnace with a volume percentage of For the high-purity argon gas with more than 99.99%, stop charging after the vacuum in the furnace rises to 1.0×10 ^-1 Pa.

Set the melting current to 150A to melt the master alloy ingot. When the master alloy ingot is about to melt, quickly adjust the melting current to 300A, aim at the center of the master alloy ingot and blow the arc at the mold hole, and open the vacuum suction casting valve at the same time, using negative pressure The instantly melted master alloy liquid was absorbed and cast into a mold to make a master alloy rod, and its XRD pattern is shown in Figure 2; the results show that the master alloy rod is a polycrystalline structure, and the polycrystalline orientation is <110>, <100> Mainly.

4. Preparation of magnetostrictive materials

Grind the outer surface of the above-prepared master alloy rod evenly, soak it in acetone together with the <100> oriented Fe ₈₃ Ga ₁₇ single crystal seed crystal, ultrasonically clean it at a frequency of 50KHz for 10min, put it in an oven after cleaning, and Dry at 120°C for 20 minutes to obtain a cleaned sample.

Directional solidification of materials is carried out in a directional solidification furnace. First, the graphite heating body is placed on the heat preservation ring, and the heat preservation ring is placed on the GaIn alloy tank; secondly, the cleaned sample is placed in an alumina crucible. The alloy rod is placed above the Fe ₈₃ Ga ₁₇ single crystal seed crystal, and the crucible is placed in the center of the cylindrical hollow graphite heating body and above the GaIn alloy tank; then the crucible is lowered into the GaIn alloy tank, so that the inside of the crucible The lower part of the Fe ₈₃ Ga ₁₇ single crystal seed crystal is immersed in the GaIn alloy in the GaIn alloy tank and the contact surface of the Fe ₈₃ Ga ₁₇ single crystal seed crystal and the master alloy rod is located above the liquid level of the GaIn alloy; at the same time, under the seed crystal A water-cooled copper jig is set, and the lower end of the seed crystal is brought into contact with the water-cooled copper jig, and the water-cooled copper jig is cooled by circulating cold water at about 5°C.

Subsequently, after vacuuming the directional solidification furnace to 3.0×10 ^-3 Pa, fill the furnace body with high-purity argon gas with a volume percentage of more than 99.99%, and wait until the vacuum degree in the furnace rises to 1.0×10 ^-1 Pa Stop inflating, repeat this step three times, and heat the graphite heating body to 1600°C at a heating rate of 35°C/min. After the master alloy rod is completely melted and the upper part of the Fe ₈₃ Ga ₁₇ single crystal seed crystal is melted, keep it warm for 10 minutes, and then use The cooling rate of 25°C/min will reduce the temperature of the graphite heating body to 1500°C, keep it at this temperature for 5 minutes, then heat the graphite heating body to 1600°C at the same heating rate and keep it warm for 10 minutes, repeat the above operation three times and then keep it warm for 30 minutes , the master alloy rod is completely melted and the Fe ₈₃ Ga ₁₇ single crystal seed crystal becomes a partially molten state in which the upper part is molten and the lower part is solidified.

Control the temperature gradient to 1×10 ⁵ K/m, and the growth rate to 20,000 mm/h. The molten material is pulled down smoothly along the lower part of the FeGa single crystal seed crystal into the GaIn alloy for directional solidification. During directional solidification, through The GaIn alloy cooling liquid cools the side of the material, and at the same time cools the lower end of the material through a water-cooled copper fixture to grow the single crystal; after the growth is completed, the temperature in the furnace is lowered to room temperature, and the grown single crystal is taken out to obtain the composition: (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 rod-shaped magnetostrictive material (size Φ7mm×20mm), its BSE image, synchrotron radiation XRD pattern and Laue diffraction pattern are shown in Figure 3 and Figure 4, respectively, Figure 3 shows that the magnetostrictive There is no RE element precipitated phase in the stretchable material. Figure 4 shows that the magnetostrictive material has a (200) diffraction peak between 2θ of 27° and 28°, and a (400) diffraction peak of 2θ of 56° to 57°. In addition, the diffraction spots of different crystal face groups of the magnetostrictive material are four-fold symmetric. This shows that the Tb element in the (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 magnetostrictive material is completely dissolved in the FeGa matrix, and the material is a <100>-oriented single crystal material.

The TEM test was carried out on the Fe ₈₃ Ga ₁₇ single crystal seed crystal and the prepared (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 magnetostrictive material, and the dark field image of the material in STEM mode was observed along the <100> crystal zone axis. The results are as follows Figure 5 and Figure 6 show. The results show that the internal microstructure of the ordinary Fe ₈₃ Ga ₁₇ single crystal is uniform (Fig. 5), while a large number of dislocation lines can be observed in the prepared (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 material, and many dislocation lines Intersect each other at one place to form radial lines radiating from this place to the surroundings, and the length of the dislocation line is 30-150nm. The reason may be that the solid solution of Tb element causes the square distortion of the FeGa matrix, and the distortion leads to the generation of dislocation in the matrix material. Internal stress, internal stress is expressed in the form of dislocation lines.

In addition, the magnetostrictive strain value of the (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 material and the Fe ₈₃ Ga ₁₇ single crystal was measured using a magnetostrictive measurement system (produced by Beijing Wuke Optoelectronics Technology Co., Ltd.), where the strain gauges are from Kyowa KFG -1-120-C1-11L3M2R resistance strain gauge, the result is shown in Figure 7. The results show that: (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 material has a saturation magnetostriction coefficient of 463ppm, which is about 50% higher than that of Fe ₈₃ Ga ₁₇ single crystal; in addition, (Fe _0.83 Ga _0.17 ) _99.95 The saturation magnetic field of Tb _0.05 material is only about 300Oe, and the magnetostrictive performance and comprehensive usability are good.

Preparation of Example 2 (Fe _0.83 Ga _0.17 ) _99.97 Lu _0.03

In addition to the batching step, weigh 28.05g of Fe, 7.242g of Ga and 0.031g of Lu for later use; in the step of preparing the magnetostrictive material, heat the graphite heating body to 1575°C, and control the temperature gradient to 5×10 ⁵ K /m, except that the growth rate is 8000mm/h, other steps are the same as in Example 1, and a magnetostrictive material (dimension Φ7mm×20mm) with a composition of (Fe _0.83 Ga _0.17 ) _99.97 Lu _0.03 is produced.

After testing, the (Fe _0.83 Ga _0.17 ) _99.97 Lu _0.03 magnetostrictive material completely dissolves the Lu element in the FeGa matrix, and the material is a <100>-oriented single crystal material; in addition, the (Fe _0.83 Ga _0.17 ) _99.97 The saturation magnetostriction coefficient of Lu _0.03 material is 330ppm, the saturation magnetic field is about 350Oe, and the magnetostriction performance and comprehensive usability are good.

Preparation of Example 3 (Fe _0.81 Ga _0.19 ) _99.96 Dy _0.04

The preparation composition is the method for the magnetostrictive material of (Fe _0.81 Ga _0.19 ) _99.96 Dy _0.04 , comprises the following steps:

1. Ingredients

Weigh 27.88g of Fe, 8.25g of Ga and 0.04g of Dy for later use.

2. Preparation of master alloy ingot

Put the above-mentioned raw materials Fe, Ga and Dy into the crucible of the vacuum non-consumable arc melting furnace, vacuumize the vacuum non-consumable arc melting furnace to 1.0×10 ^-3 Pa, and fill the furnace body with For high-purity argon with a purity of more than 99.99%, stop inflating after the vacuum degree in the furnace rises to 5.0×10 ^-1 Pa. After repeating this step three times, set the melting current to 120A to melt the raw materials. The time for the first smelting is about 5 minutes, and the smelting is repeated four times to obtain the master alloy ingot.

3. Preparation of master alloy rods

Place the master alloy ingot prepared above in a vacuum non-consumable arc melting furnace, and after the vacuum non-consumable arc melting furnace is evacuated to 1.0×10 ^-3 Pa, fill the furnace body with The high-purity argon gas is used, and the gas filling is stopped after the vacuum degree in the furnace rises to 5.0×10 ^-1 Pa.

Set the melting current to 120A to melt the master alloy ingot. When the master alloy ingot is about to melt, quickly adjust the melting current to 300A, aim at the center of the master alloy ingot and blow the arc at the mold hole, and open the vacuum suction casting valve at the same time, using negative pressure The instantly melted master alloy liquid is suction-cast into a mold to make a master alloy rod, which has a polycrystalline structure, and the polycrystalline orientation is mainly <110> and <100>.

4. Preparation of magnetostrictive materials

The above-prepared master alloy rod and <100> oriented Fe ₈₁ Ga ₁₉ single crystal seed crystal were cleaned to obtain a cleaned sample.

Use a directional solidification furnace to directional solidify the material. After placing the material according to the method in Example 1, evacuate the directional solidification furnace to 1.0×10 ^-3 Pa, and fill the furnace body with high-purity argon gas with a purity of more than 99.99%. After the vacuum degree in the furnace rises to 5.0×10 ^-1 Pa, stop inflating. After repeating this step three times, heat the graphite heating body to 1575°C at a heating rate of 40°C/min. After the master alloy rod is completely melted and the Fe ₈₁ Melt the upper part of the Ga ₁₉ single crystal seed and keep it warm for 5 minutes, then lower the temperature of the graphite heating body to 1500 °C at a cooling rate of 30 °C/min, keep it at this temperature for 3 minutes, and then heat the graphite heating body at the same heating rate Heat to 1575°C and hold for 5 minutes, repeat the above operation three times and then hold for 30 minutes, the master alloy rod is completely melted and the Fe ₈₁ Ga ₁₉ single crystal seed crystal becomes a partially molten state in which the upper part is molten and the lower part is solidified.

Control the temperature gradient to 4×10 ⁵ K/m, and the growth rate to 5000mm/h. The molten material is pulled down smoothly along the lower part of the FeGa single crystal seed crystal into the GaIn alloy for directional solidification. During directional solidification, through The GaIn alloy cooling liquid cools the side of the material, and at the same time cools the lower end of the material through a water-cooled copper fixture to grow the single crystal; after the growth is completed, the temperature in the furnace is lowered to room temperature, and the grown single crystal is taken out to obtain the composition: (Fe _0.81 Ga _0.19 ) _99.96 Dy _0.04 magnetostrictive material (size Φ7mm×20mm).

It has been detected that the Dy element in the (Fe _0.81 Ga _0.19 ) _99.96 Dy _0.04 magnetostrictive material is completely dissolved in the FeGa matrix, and the material is a <100>-oriented single crystal material; in addition, the (Fe _0.81 Ga _0.19 ) _99.96 The saturation magnetostriction coefficient of the Dy _0.04 material is 454ppm, the saturation magnetic field is about 300Oe, and the magnetostriction performance and comprehensive usability are good.

Preparation of Example 4 (Fe _0.82 Ga _0.18 ) _99.98 Sm _0.02

In addition to the batching step, 28.12g of Fe, 7.79g of Ga and 0.019g of Sm were weighed for subsequent use; in the step of preparing magnetostrictive material, Fe ₈₂ Ga ₁₈ single crystal seed crystal was used as the seed crystal, and the temperature gradient was controlled to be 10 ×10 ⁵ K/m, except that the growth rate is 1000mm/h, the other steps are the same as in Example 1, and a magnetostrictive material (dimension Φ7mm×20mm) with a composition of (Fe _0.82 Ga _0.18 ) _99.98 Sm _0.02 is obtained.

After testing, the Sm element in the (Fe _0.82 Ga _0.18 ) _99.98 Sm _0.02 magnetostrictive material is completely dissolved in the FeGa matrix, and the material is a <100>-oriented single crystal material; in addition, the (Fe _0.82 Ga _0.18 ) _99.98 The saturation magnetostriction coefficient of the Sm _0.02 material is 315ppm, the saturation magnetic field is about 400Oe, and the magnetostriction performance and comprehensive usability are good.

Preparation of (Fe _0.81 Ga _0.19 ) _99.9 Tm _0.1 in Example 5

The method for preparing the magnetostrictive material whose composition is (Fe _0.81 Ga _0.19 ) _99.9 Tm _0.1 comprises the following steps:

1. Ingredients

Weigh 27.76g of Fe, 8.21g of Ga and 0.105g of Tm for later use.

2. Preparation of master alloy ingot

Put the above-mentioned raw materials Fe, Ga and Tm into the crucible of the vacuum non-consumable arc melting furnace, vacuumize the vacuum non-consumable arc melting furnace to 5.0×10 ^-2 Pa, and fill the furnace body with For high-purity argon gas with a purity of more than 99.99%, stop inflating after the vacuum degree in the furnace rises to 1.0×10 ^-1 Pa. After repeating this step three times, set the melting current to 100A to melt the raw materials. The time for the first smelting is about 5 minutes, and the smelting is repeated four times to obtain the master alloy ingot.

3. Preparation of master alloy rods

Place the master alloy ingot prepared above in a vacuum non-consumable arc melting furnace, and after the vacuum non-consumable arc melting furnace is evacuated to 5.0×10 ^-2 Pa, fill the furnace body with The high-purity argon gas is used, and the gas filling is stopped after the vacuum degree in the furnace rises to 1.0×10 ^-1 Pa.

Set the melting current to 100A to melt the master alloy ingot. When the master alloy ingot is about to melt, quickly adjust the melting current to 300A, aim at the center of the master alloy ingot and blow the arc at the mold hole, and open the vacuum suction casting valve at the same time, using negative pressure The instantly melted master alloy liquid is suction-cast into a mold to make a master alloy rod, which has a polycrystalline structure, and the polycrystalline orientation is mainly <110> and <100>.

4. Preparation of magnetostrictive materials

The above-prepared master alloy rod and <100> oriented Fe ₈₁ Ga ₁₉ single crystal seed crystal were cleaned to obtain a cleaned sample.

Use a directional solidification furnace to directional solidify the material. After placing the material according to the method in Example 1, vacuum the directional solidification furnace to 5.0×10 ^-2 Pa, and fill the furnace body with high-purity argon gas with a purity of more than 99.99%. After the vacuum degree in the furnace rises to 1.0×10 ^-1 Pa, stop inflating. After repeating this step three times, heat the graphite heating body to 1650°C at a heating rate of 30°C/min. After the master alloy rod is completely melted and the Fe ₈₁ Melt the upper part of the Ga ₁₉ single crystal seed crystal and keep it warm for 15 minutes, then lower the temperature of the graphite heating body to 1500 °C at a cooling rate of 20 °C/min, keep it at this temperature for 8 minutes, and then heat the graphite heating body at the same heating rate to 1650°C and keep it warm for 15 minutes, repeat the above operation three times and keep it warm for 35 minutes, the master alloy rod is completely melted and the Fe ₈₁ Ga ₁₉ single crystal seed crystal becomes a partially molten state in which the upper part is molten and the lower part is solidified.

Control the temperature gradient to 5×10 ⁵ K/m, and the growth rate to 6000mm/h. The molten material is pulled down smoothly along the lower part of the FeGa single crystal seed crystal into the GaIn alloy for directional solidification. During directional solidification, through The GaIn alloy cooling liquid cools the side of the material, and at the same time cools the lower end of the material through a water-cooled copper fixture to grow the single crystal; after the growth is completed, the temperature in the furnace is lowered to room temperature, and the grown single crystal is taken out to obtain the composition: (Fe _0.81 Ga _0.19 ) _99.9 Tm _0.1 magnetostrictive material (size Φ7mm×20mm).

After testing, the Tm element in the (Fe _0.81 Ga _0.19 ) _99.9 Tm _0.1 magnetostrictive material is completely dissolved in the FeGa matrix, and the material is a <100>-oriented single crystal material; in addition, the (Fe _0.81 Ga _0.19 ) _99.9 The saturation magnetostriction coefficient of Tm _0.1 material is 667ppm, the saturation magnetic field is about 370Oe, and the magnetostriction performance and comprehensive usability are good.

Preparation of Example 6 (Fe _0.81 Ga _0.19 ) _99.8 La _0.2

In addition to the batching step, weigh 27.55g of Fe, 8.15g of Ga, and 0.086g of La for later use; in the step of preparing magnetostrictive materials, use Fe ₈₁ Ga ₁₉ single crystal seed crystal as the seed crystal, and heat the graphite heating body to 1650°C, except that the temperature gradient is controlled to be 8×10 ⁵ K/m, and the growth rate is 7000 mm/h, the other steps are the same as in Example 1, and a magnetotropic film with a composition of (Fe _0.81 Ga _0.19 ) _99.8 La _0.2 is obtained. Telescopic material (size Φ7mm×20mm).

It has been detected that the (Fe _0.81 Ga _0.19 ) _99.8 La _0.2 magnetostrictive material completely dissolves the La element into the FeGa matrix, and the material is a <100>-oriented single crystal material; in addition, the (Fe _0.81 Ga _0.19 ) _99.8 The saturation magnetostriction coefficient of the La _0.2 material is 1316ppm, the saturation magnetic field is about 500Oe, and the magnetostriction performance and comprehensive usability are good.

Preparation of Example 7 (Fe _0.82 Ga _0.18 ) _99.8 (HoEr) _0.2

In addition to the batching step, take 27.3g of Fe, 7.55g of Ga, 0.099g of Ho and 0.1g of Er for subsequent use; in the step of preparing magnetostrictive material, adopt Fe ₈₂ Ga ₁₈ single crystal seed crystal as seed crystal, and The graphite heating body was heated to 1650°C, and the temperature gradient was controlled to be 3×10 ⁵ K/m, and the growth rate was 4000mm/h. The other steps were the same as in Example 1, and the obtained composition was (Fe _0.82 Ga _0.18 ) _99.8 (HoEr) _0.2 magnetostrictive material (size Φ7mm×20mm).

After testing, the (Fe _0.82 Ga _0.18 ) _99.8 (HoEr) _0.2 magnetostrictive material is a <100> oriented single crystal material; in addition, the saturation magnetostrictive coefficient of the (Fe _0.82 Ga _0.18 ) _99.8 (HoEr) _0.2 material It is 1120ppm, the saturation magnetic field is about 490Oe, and the magnetostrictive performance and comprehensive usability are good.

Preparation of Example 8 (Fe _0.83 Ga _0.17 ) _99.84 (SmTm) _0.16

Except in the batching step, the Fe of 28.39g, the Ga of 7.33g, the Sm of 0.075g and the Tm of 0.084g are standby; 2×10 ⁵ K/m, except that the growth rate is 10000mm/h, the other steps are the same as in Example 1 _, and the _{magnetostrictive} material (size _Φ7mm × _20mm ).

After testing, the Sm and Tm elements in the (Fe _0.83 Ga _0.17 ) _99.84 (SmTm) _0.16 magnetostrictive material are completely dissolved in the FeGa matrix, and the material is a <100>-oriented single crystal material; in addition, the (Fe _0.83 The saturation magnetostriction coefficient of Ga _0.17 ) _99.84 (SmTm) _0.16 material is 998ppm, the saturation magnetic field is about 500Oe, and the magnetostriction performance and comprehensive usability are good.

Preparation of Example 9 (Fe _0.82 Ga _0.18 ) _99.85 (HoErTm) _0.15

In addition to the batching step, weigh 28.53g of Fe, 7.63g of Ga, 0.052g of Ho, 0.052g of Er and 0.053g of Tm for later use; in the step of preparing magnetostrictive materials, use Fe _82.5 Ga _17.5 single crystal seed As a seed crystal, the graphite heating body is heated to 1675°C, and the temperature gradient is controlled to be 5×10 ⁵ K/m, and the growth rate is 3000 mm/h. The other steps are the same as in Example 1, and the obtained composition is (Fe _0.82 Ga _0.18 ) _99.85 (HoErTm) _0.15 magnetostrictive material (size Φ7mm×20mm).

After testing, the Ho, Er and Tm elements in the (Fe _0.82 Ga _0.18 ) _99.85 (HoErTm) _0.15 magnetostrictive material are completely dissolved in the FeGa matrix, and the material is a <100>-oriented single crystal material; in addition, the ( The saturation magnetostriction coefficient of Fe _0.82 Ga _0.18 ) _99.85 (HoErTm) _0.15 material is 1015ppm, the saturation magnetic field is about 500Oe, and the magnetostriction performance and comprehensive usability are good.

Preparation of Example 10 (Fe _0.81 Ga _0.19 ) _99.85 (TbDyHo) _0.15

In addition to the batching step, weigh 27.92g of Fe, 8.26g of Ga, 0.049g of Tb, 0.05g of Dy and 0.051g of Ho for later use; in the step of preparing magnetostrictive material, use Fe ₈₁ Ga ₁₉ single crystal seed As a seed crystal, the graphite heating body is heated to 1650°C. In addition, the temperature gradient is controlled to be 1×10 ⁵ K/m, and the growth rate is 15000 mm/h. The other steps are the same as in Example 1, and the obtained composition is (Fe _0.81 Ga _0.19 ) _99.85 (TbDyHo) _0.15 magnetostrictive material (size Φ7mm×20mm).

After testing, the Tb, Dy and Ho elements in the (Fe _0.81 Ga _0.19 ) _99.85 (TbDyHo) _0.15 magnetostrictive material are completely dissolved in the FeGa matrix, and the material is a <100>-oriented single crystal material; in addition, the ( The saturation magnetostriction coefficient of Fe _0.81 Ga _0.19 ) _99.85 (TbDyHo) _0.15 material is 1300ppm, the saturation magnetic field is about 490Oe, and the magnetostriction performance and comprehensive usability are good.

Comparative example 1

The master alloy rod prepared in Example 1 was cleaned to obtain a cleaned sample. Put the cleaned sample into the alumina crucible of the directional solidification furnace, and after vacuuming the directional solidification furnace to 3.0×10 ^-3 Pa, fill the furnace body with high-purity argon gas with a purity of more than 99.99%, and wait for the furnace to vacuum After the temperature rises to 1.0×10 ^-1 Pa, the inflation is stopped. After repeating this step three times, the master alloy rod is heated to a molten state at about 1600°C.

Control the temperature gradient to 1×10 ² K/m, and the growth rate to 500mm/h, draw the molten material into the GaIn alloy smoothly, and perform single crystal growth during directional solidification; after the growth is completed, lower the temperature in the furnace to After cooling down to room temperature, the grown single crystal was taken out to obtain a magnetostrictive material (diameter Φ7mm×20mm) with a composition of (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 .

It was detected that the Tb element in the (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 magnetostrictive material did not completely dissolve into the FeGa matrix, but was pinned at the grain boundary by precipitation, and the material was <100> and <110> oriented polycrystalline material; in addition, the saturation magnetostriction coefficient of the (Fe _0.83 Ga _0.17 ) _99.95 Tb _0.05 material is about 300ppm, and the performance of the material has not been significantly improved.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (6)

1. a kind of magnetostriction materials, it is characterised in that its composition is (Fe_1-xGa_x)_100-yRE_y, wherein 0.17≤x≤0.19, The one or more of 0.01≤y≤0.2, RE in Tb, La, Sm, Dy, Lu, Ho, Er and Tm；

It is<100>The monocrystal material of orientation；

Saturation magnetic field is 100~500Oe, and saturation magnetostriction constant is up to 300~1500ppm.

2. magnetostriction materials according to claim 1, it is characterised in that its composition is (Fe_0.83Ga_0.17)_99.95Tb_0.05、 (Fe_0.83Ga_0.17)_99.95Sm_0.05、(Fe_0.83Ga_0.17)_99.95Dy_0.05、(Fe_0.83Ga_0.17)_99.95Ho_0.05、(Fe_0.83Ga_0.17)_99.95Er_0.05、(Fe_0.83Ga_0.17)_99.95Tm_0.05、(Fe_0.81Ga_0.19)_99.95Tb_0.05、(Fe_0.81Ga_0.19)_99.95Sm_0.05、 (Fe_0.81Ga_0.19)_99.95Dy_0.05、(Fe_0.81Ga_0.19)_99.95Ho_0.05、(Fe_0.81Ga_0.19)_99.95Er_0.05、(Fe_0.81Ga_0.19)_99.95Tm_0.05、(Fe_0.83Ga_0.17)_99.97Lu_0.03、(Fe_0.81Ga_0.19)_99.96Dy_0.04、(Fe_0.82Ga_0.18)_99.98Sm_0.02、 (Fe_0.81Ga_0.19)_99.9Tm_0.1、(Fe_0.81Ga_0.19)_99.8La_0.2、(Fe_0.82Ga_0.18)_99.8(HoEr)_0.2、(Fe_0.83Ga_0.17)_99.84 (SmTm)_0.16、(Fe_0.82Ga_0.18)_99.85(HoErTm)_0.15Or (Fe_0.81Ga_0.19)_99.85(TbDyHo)_0.15。

3. the preparation method of any magnetostriction materials of claim 1 to 2, it is characterised in that comprise the following steps：

1) Fe, Ga and RE raw material are equipped with according to the component requirements of magnetostriction materials；

2) Fe, Ga and RE raw material of outfit are smelted into mother alloy ingot；

3) mother alloy ingot is melted, and foundry alloy rod is made by suction pouring；

4) by the foundry alloy rod and<100>The FeGa single crystal seeds of orientation are placed in apparatus for directional solidification, and make FeGa monocrystalline Coolant is immersed in seed crystal bottom, and after being vacuumized to apparatus for directional solidification and being filled with protective gas, heating makes foundry alloy rod completely molten Melt and FeGa single crystal seeds top melts, the material of melting is carried out along FeGa single crystal seeds bottom pull into coolant Directional solidification, and control the directional solidification thermograde be 1 × 10⁵~9 × 10⁵K/m, the speed of growth be 1000~ 20000mm/h, the magnetostriction materials are made；

In step 4), the foundry alloy rod and FeGa single crystal seeds top are placed in the inside of hollow graphite calandria, pass through sense Graphite heating body described in coil heats is answered, so that the melting completely of foundry alloy rod and the melting of FeGa single crystal seeds top；

In step 4), the heating includes implementing following operation at least once：

Graphite heating body is heated to 1550~1700 DEG C with 30~40 DEG C/min programming rate, treats that foundry alloy rod and FeGa are mono- 5~15min is incubated after the melting of grain of crystallization crystalline substance top, is then cooled to graphite heating body with 20~30 DEG C/min cooling rate 1450~1550 DEG C and 3~8min is incubated, then graphite heating body is heated to 1550 with 30~40 DEG C/min programming rate~ 1700 DEG C and 5~15min of insulation；

In step 4), make FeGa single crystal seeds bottom immersion coolant and lower end in contact water-cooled metal part, the coolant are Ga-In alloys.

4. preparation method according to claim 3, it is characterised in that in step 4), vacuumized simultaneously to apparatus for directional solidification Being filled with protective gas includes implementing following operation at least once：

1.0 × 10 are evacuated to apparatus for directional solidification^-3~5.0 × 10^-3Protective gas is filled with after Pa, is treated in apparatus for directional solidification Vacuum rise to 1.0 × 10^-1~5 × 10^-1Stop inflation after Pa.

5. according to any described preparation method of claim 3 to 4, it is characterised in that step 2) includes：

Fe, Ga and RE raw material of outfit are placed in smelting equipment, 5.0 × 10 are evacuated to smelting equipment^-2~5.0 × 10^{- 3}Protective gas is filled with after Pa, treats that the vacuum in smelting equipment rises to 1.0 × 10^-1~5.0 × 10^-1Stop inflation after Pa, it is real After applying aforesaid operations at least once, under conditions of melting electric current is 100~150A melting raw material once more than, control molten every time The time of refining is 3~5 minutes, and mother alloy ingot is made.

6. according to any described preparation method of claim 3 to 4, it is characterised in that step 3) includes：

The mother alloy ingot is placed in smelting equipment, 1.0 × 10 are evacuated to smelting equipment^-3~5.0 × 10^-3Filled after Pa Enter protective gas, treat that the vacuum in smelting equipment rises to 1.0 × 10^-1~5.0 × 10^-1Stop inflation after Pa, in melting electricity Flow for the mother alloy ingot is fused into aluminium alloy under conditions of 100~300A, and aluminium alloy is inhaled into casting and is made into mould Foundry alloy rod.