A Z-type hexagonal ferrite magnetoelectric coupling ceramic material and its preparation method

Abstract

This invention discloses a Z-type hexagonal ferrite magnetoelectric coupling ceramic material and its preparation method; belonging to the field of magnetoelectric coupling materials. This invention aims to solve the problems of existing multiferroic materials having limited ferroelectric and ferromagnetic properties, low magnetoelectric coupling strength, and low magnetoelectric coupling tolerance temperature. The chemical formula of the material of this invention is: Ba. x Sr 3‑x Co 1.25 Cu 0.75 Fe 24 O 41 Where x = 0 to 3; prepared by a staged sintering method under an oxygen atmosphere. The product of this invention possesses both ferroelectric and ferromagnetic properties, along with strong magnetoelectric coupling performance. This product can achieve magnetoelectric coupling performance induced under a small external magnetic field, and its dynamic magnetoelectric coupling performance can be controlled by changing the direction of the pre-polarized electric field and the applied sweep field. Furthermore, under a certain Ba doping ratio, it surpasses the dynamic magnetoelectric coupling performance at room temperature, and can be applied in the field of magnetoelectric coupling. This enriches and broadens the application range of magnetoelectric materials, possessing potential application advantages.

Description

Technical Field

[0001] This invention belongs to the field of magnetoelectric coupling materials technology, specifically, it relates to a Z-type hexagonal ferrite magnetoelectric coupling ceramic material and its preparation method. Background Technology

[0002] Magnetoelectric coupling materials refer to materials whose ferroelectric polarization or magnetic state changes under the influence of an external magnetic or electric field. In other words, an electric field can control the magnetic state of a material, or an external magnetic field can control its ferroelectric polarization. Among these, multiferroic materials, due to their simultaneous ferroelectric, ferromagnetic, or ferroelastic order and magnetoelectric coupling effects, show promising applications in microwave, sensing and control, and information storage fields, and are increasingly becoming a research hotspot for scientists.

[0003] Chinese patent application CN201711172802.0, entitled "Bismuth Ferrite Room Temperature Multiferroelectric Coupling Material and Preparation Method Thereof, Electronic Device", discloses a bismuth ferroelectric room temperature multiferroelectric coupling material. The structural formula of this material is AB. x O y It has a hexagonal crystal structure. A is one or more of Bi, Pb, Sb, Sn, or rare earth metals, and B is one or more of transition metals Fe, Sc, Ti, V, Cr, Mn, Co, Ni, Zn, and Cu. This material simultaneously exhibits ferroelectricity and ferrimagnetism with a transition temperature above room temperature. It is ferroelectric at 800 K or less, and ferromagnetic or ferrimagnetic at 600 K or less. Below 600 K, the ferroelectricity and ferromagnetism or ferrimagnetism of the bismuth ferrite room temperature multiferromagnetic-electric coupling material coexist. It is prepared by heating a material containing the ABO component to generate molecular beams, atomic beams, or plasma and depositing them onto a substrate. Summary of the Invention

[0004] This invention aims to address the problems of limited variety of existing multiferroic materials exhibiting both ferroelectric and ferromagnetic properties, low magnetoelectric coupling strength, and low magnetoelectric coupling tolerance temperatures that are difficult to exceed room temperature. It provides a Z-type hexagonal ferrite magnetoelectric coupling ceramic material and its preparation method. The Z-type hexagonal ferrite magnetoelectric coupling ceramic material of this invention simultaneously possesses both ferroelectric and ferromagnetic properties and exhibits a strong magnetoelectric coupling effect, while its magnetoelectric coupling tolerance temperature exceeds room temperature limitations. The Z-type hexagonal ferrite magnetoelectric coupling ceramic material of this invention can induce polarization performance in samples under a small applied magnetic field, and the polarization direction of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material can be controlled by adjusting the direction of the pre-polarization electric field and the direction of the magnetic field sweep. Furthermore, the preparation process of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material of this invention is simple, thus broadening the application of ferrite magnetoelectric coupling ceramic materials in the field of magnetoelectric coupling.

[0005] The Z-type hexagonal ferrite magnetoelectric coupling ceramic material of this invention possesses both ferroelectric and ferromagnetic properties, and its dynamic magnetoelectric coupling performance can be modulated by an applied small magnetic field. Furthermore, the dynamic magnetoelectric coupling performance of this Z-type hexagonal ferrite magnetoelectric coupling ceramic material changes with the direction of the external magnetic field. The direction of the dynamic magnetoelectric coupling performance of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material can be effectively controlled by using positive and negative polarized electric fields. The dynamic magnetoelectric coupling performance induced by the external magnetic field of this invention exceeds room temperature tolerance, breaking the bottleneck problem in the field of magnetoelectric coupling where the tolerance temperature is at or below room temperature, laying a solid foundation for the practical application of magnetoelectric coupling materials in environmental conditions at and above room temperature. The method used in this invention is the traditional solid-state sintering method, which has a simple preparation process and produces high-quality samples with excellent performance.

[0006] To address the aforementioned technical problems, the present invention adopts the following technical solution:

[0007] The purpose of this invention is to provide a Z-type hexagonal ferrite magnetoelectric coupling ceramic material with the chemical formula Ba. x Sr 3-x Co 1.25 Cu 0.75 Fe 24 O 41 , where x = 0 to 3. Specifically, it is prepared according to the following steps:

[0008] Step 1: According to the chemical formula Ba of the Z-type hexagonal ferrite x Sr 3-x Co 1.25 Cu 0.75 Fe 24 O 41 BaCO3, SrCO3, Co3O4, CuO and Fe2O3 were weighed out according to their stoichiometric ratios and then placed together in a ball mill jar for wet ball milling. After ball milling, the mixture was dried and then placed back into the ball mill jar for dry ball milling to obtain a mixed powder.

[0009] Step 2: Place the mixed powder obtained in Step 1 into an alumina crucible, then transfer it to a box furnace, heat it to 1000℃-1140℃ at a rate of 5℃ / min and hold it for 10h, then cool it down to 500℃ at a rate of 5℃ / min and stop the sintering process; allow it to cool naturally to room temperature to obtain pre-calcined powder.

[0010] Step 3: Place the pre-calcined powder obtained in Step 2 into a ball mill jar for wet ball milling; after ball milling, dry it, and then place it into a ball mill jar for dry ball milling to obtain coarse material powder.

[0011] Step 4: Add polyvinyl alcohol (PVA) solution dropwise to the coarse material powder obtained in Step 3, grind evenly, sieve, and press into sheets to obtain block green bodies;

[0012] Step 5: Place the block blank obtained in Step 4 into a box furnace, heat it to a certain temperature and hold it for a certain time to remove the glue, and obtain a glue-removed blank.

[0013] Step 6: Place the debonded preform obtained in Step 5 into a box furnace. In an air atmosphere, heat the box furnace to 1000℃ at a rate of 5℃ / min. Then, heat the sample to 1100℃-1140℃ at a rate of 2℃ / min and hold for 10 hours. Then, cool it down to 1000℃ at a rate of 2℃ / min. Finally, cool it down to 500℃ at a rate of 5℃ / min and turn off the program. Allow it to cool naturally to room temperature to obtain Z-type hexagonal ferrite.

[0014] Step 7: Place the Z-type hexagonal ferrite obtained in Step 6 into a tube furnace. Under an oxygen atmosphere, heat the tube furnace to 950°C at a rate of 5°C / min and hold for 14 days. Then, cool it down to 500°C at a rate of 5°C / min and stop the sintering process. Allow it to cool naturally to room temperature to obtain the Z-type hexagonal ferrite magnetoelectric coupling ceramic material.

[0015] To further specify, the wet ball milling described in step one involves adding the raw materials BaCO3, SrCO3, Co3O4, CuO and Fe2O3 into the ball mill jar of a planetary ball mill, then adding 140 mL of 95% ethanol, and the ball mill jar contains approximately 30 balls. The mixture is then ball-milled at a speed of 400 r / min for 12 hours.

[0016] To further specify, the drying process described in step one involves maintaining the oven at a temperature of 90°C for 8 hours.

[0017] To further specify, the dry ball milling described in step one involves adding the material into the grinding jar of a planetary ball mill, with 30 balls in the grinding jar, and milling at a speed of 500 r / min for 10 min.

[0018] To further specify, step four involves passing the material through a 100-mesh sieve.

[0019] Further specifying, in step four, the sieved powder is compressed into tablets using a tablet press under a pressure of 6 MPa.

[0020] Further specifying, the mass percentage concentration of the polyvinyl alcohol (PVA) solution mentioned in step four is 5%; the material is added according to the ratio of 10 drops of 5% polyvinyl alcohol (PVA) solution to 5g of crude material powder.

[0021] Further specifying, in step five, the temperature is raised to 500℃ and maintained for 10 hours for glue removal.

[0022] Further specifying, in step seven, oxygen is introduced into the furnace tubes of the tubular furnace at a flow rate of 100 mL / min to obtain an oxygen atmosphere.

[0023] The Z-type hexagonal ferrite magnetoelectric coupling ceramic material Ba of the present invention x Sr 3-x Co 1.25 Cu 0.75 Fe 24 O 41 (x=0~3) exhibits good magnetoelectric coupling performance, especially when x=0.2-1.8, Ba x Sr 3-x Co 1.25 Cu 0.75 Fe 24 O 41 (x = 0.2–1.8) exhibits a phenomenon where the dynamic magnetoelectric coupling coefficient signal response flips with the applied sweep field under low-temperature conditions of 78K, and the pre-polarized electric field can effectively control the dynamic magnetoelectric coupling coefficient signal response of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material. Especially when x = 0.2–1.0, Ba… x Sr 3-x Co 1.25 Cu 0.75 Fe 24 O 41 (x=0.2~1.0) It still exhibits dynamic magnetoelectric coupling response at room temperature (300K) and above, and its maximum withstand temperature reaches 350K. Ba x Sr 3- x Co 1.25 Cu 0.75 Fe 24 O 41 (x=0.2~1.0) exhibits a phenomenon where the dynamic magnetoelectric coupling coefficient signal response flips with the applied sweep field at room temperature (300K), and the pre-polarized electric field can effectively regulate the dynamic magnetoelectric coupling coefficient signal response of the sample.

[0024] The innovation of this application lies in achieving the desired Ba-Sr ratio in the Z-type hexagonal ferrite magnetoelectric coupling ceramic material by adjusting the ratio of Ba and Sr in the Z-type hexagonal ferrite. x Sr 3-x Co 1.25 Cu 0.75 Fe 24 O 41By regulating the magnetoelectric coupling performance of (x=0~3), Z-type hexagonal ferrite magnetoelectric coupling ceramic materials with dynamic magnetoelectric coupling performance were screened and prepared. The magnetoelectric coupling performance of some Z-type hexagonal ferrite magnetoelectric coupling ceramic materials exceeded the room temperature (300K), and even the highest temperature reached 350K, which broadened the application of the material in the field of magnetoelectric coupling.

[0025] The Z-type hexagonal ferrite magnetoelectric coupling ceramic material of the present invention is prepared by a traditional solid-state sintering method, which is simple and has low equipment requirements.

[0026] The Z-type hexagonal ferrite magnetoelectric coupling ceramic material of this invention possesses both ferroelectric and ferromagnetic properties, along with strong magnetoelectric coupling performance. This Z-type hexagonal ferrite magnetoelectric coupling ceramic material can induce dynamic magnetoelectric coupling performance under a small applied magnetic field. Furthermore, the dynamic magnetoelectric coupling coefficient signal of this Z-type hexagonal ferrite magnetoelectric coupling ceramic material can be modulated by changing the direction of the pre-polarized electric field and the magnetic field sweep. Some Z-type hexagonal ferrite magnetoelectric coupling ceramic materials have achieved dynamic magnetoelectric coupling response at room temperature and above, and can be applied in the field of magnetoelectric coupling. This enriches and broadens the application range of magnetoelectric materials and has potential application advantages.

[0027] To further understand the features and technical content of this invention, please refer to the following detailed description and accompanying drawings. However, the accompanying drawings are for reference and illustration only and are not intended to limit the invention. Attached Figure Description

[0028] Figure 1 Sr3Co from Examples 1 to 12 1.25 Cu 0.75 Fe 24 O 41， Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.2 Sr 1.8 Co 1.25 Cu0.75 Fe 24 O 41， Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.2 Sr 0.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba3Co 1.25 Cu 0.75 Fe 24 O 41 Scanning electron microscope images;

[0029] Figure 2 Sr3Co from Examples 1 to 12 1.25 Cu 0.75 Fe 24 O 41， Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe24 O 41， Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.2 Sr 0.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba3Co 1.25 Cu 0.75 Fe 24 O 41 XRD patterns;

[0030] Figure 3 Example 1: Sr3Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0031] Figure 4 This is Example 2Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0032] Figure 5 This is Example 3Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0033] Figure 6 This is Example 4Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0034] Figure 7 This is Example 5Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0035] Figure 8 This is Example 6Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0036] Figure 9 This is Example 7Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0037] Figure 10 This is Example 8Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0038] Figure 11 It is Example 9Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0039] Figure 12 This is Example 10Ba 2.2 Sr 0.8 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0040] Figure 13 This is Example 11Ba 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions.

[0041] Figure 14 Example 12 Ba3Co 1.25 Cu 0.75 Fe 24 O 41 Performance of dynamic magnetoelectric coupling induced by magnetic field under positive and negative polarization electric field conditions. Detailed Implementation

[0042] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, while not limiting the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0043] Example 1: The chemical formula of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material in this example is Sr3Co. 1.25 Cu 0.75 Fe 24 O 41 It is prepared according to the following steps:

[0044] Step 1: Press Z-type hexagonal ferrite Sr3Co 1.25 Cu 0.75 Fe 24 O41 Weigh out 0 g BaCO3, 6.6433 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO and 28.7438 g Fe2O3 according to the stoichiometric ratio, then put them into a ball mill jar, add 140 mL of 95% ethanol, and ball mill at 400 r / min for 12 h. After ball milling, dry them in an oven at 90℃ for 4 hours, then put them back into the ball mill jar and ball mill at 500 r / min for 10 min. The number of balls in the ball mill jar is about 30, and a mixed powder is obtained.

[0045] Step 2: Place the mixed powder obtained in Step 1 into an alumina crucible, then transfer it to a box furnace, heat it to 1000℃ at a rate of 5℃ / min and hold it for 10 hours, then cool it down to 500℃ at a rate of 5℃ / min and then turn off the program; allow it to cool naturally to room temperature to obtain pre-calcined powder.

[0046] Step 3: Place the pre-calcined powder obtained in Step 2 into a ball mill jar, add 140 mL of 95% ethanol, and ball mill at 400 r / min for 12 h. After ball milling, place it in an oven at 90℃ for 8 h to dry. After drying, place it back into the ball mill jar with approximately 30 balls and ball mill at 500 r / min for 10 min to obtain coarse material powder.

[0047] Step 4: Add 10 drops of 5% polyvinyl alcohol (PVA) solution to 5g of the coarse material powder obtained in Step 3, grind in an agate mortar for 1 hour, then pass through a 100-mesh sieve, and use a tablet press to press the sieved powder into tablets under a pressure of 6MPa to obtain a block blank.

[0048] Step 5: Place the block blank obtained in Step 5 into a box furnace, heat it to 500℃ and keep it for 10 hours to remove the glue, and obtain the glue-removed blank.

[0049] Step 6: Place the debonded blank obtained in Step 5 into a box furnace. Heat the box furnace to 1000℃ at a rate of 5℃ / min in an air atmosphere. Then heat the debonded blank to 1100℃-1140℃ at a rate of 2℃ / min and hold for 10 hours. Then cool it down to 1000℃ at a rate of 2℃ / min. Then cool it down to 500℃ at a rate of 5℃ / min and turn off the program. Then let it cool naturally to room temperature to obtain the Z-type hexagonal ferrite sintered under air atmosphere conditions.

[0050] Step 7: Place the Z-shaped hexagonal ferrite obtained in Step 6 into a tube furnace. Introduce oxygen into the furnace tubes at a flow rate of 200 mL / min to obtain an oxygen atmosphere. Simultaneously, heat the tube furnace to 950℃ at a rate of 5℃ / min and hold for 14 days. Then, cool it down to 500℃ at a rate of 5℃ / min to shut off the program, and allow it to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Sr3Co. 1.25 Cu 0.75 Fe 24 O 41 (As a comparative example)

[0051] Example 2: The chemical formula of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material in this example is Ba. 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The preparation method differs from Example 1 in that steps one and seven are replaced by the following operations:

[0052] Step one is as follows: Press the Z-type hexagonal ferrite Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The stoichiometric ratio of 0.5920 g BaCO3, 6.2004 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 was weighed out and placed in a ball mill jar. 140 mL of 95% ethanol was added. The number of balls in the ball mill jar was 30. The mixture was ball milled at 400 r / min for 12 h. After ball milling, the mixture was dried in an oven at 90℃ for 8 h. After drying, it was placed back into the ball mill jar and ball milled at 500 r / min for 10 min to obtain a mixed powder.

[0053] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba. 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0054] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0055] Example 3: The chemical formula of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material in this example is Ba. 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The preparation method differs from Example 1 in steps one and seven, which are replaced by the following operations:

[0056] Step one is as follows: Press the Z-type hexagonal ferrite Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 Weigh out 1.7760 g BaCO3, 5.3146 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 according to the stoichiometric ratio, then place them in a ball mill jar, add 140 mL of 95% ethanol, and add approximately 30 balls to the ball mill jar. Ball mill at 400 r / min for 12 h. After ball milling, place the mixture in an oven at 90℃ for 8 h to dry, then place it back in the ball mill jar, with approximately 30 balls, and ball mill at 500 r / min for 10 min to obtain a mixed powder.

[0057] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba. 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0058] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0059] Example 4: The chemical formula of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material in this example is Ba. 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41The preparation method differs from Example 1 in that steps one and seven are replaced by the following operations:

[0060] Step one is as follows: Press the Z-type hexagonal ferrite Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 Weigh out 2.9600 g BaCO3, 4.4289 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 according to the stoichiometric ratio, then place them in a ball mill jar, add 140 mL of 95% ethanol, and add approximately 30 balls to the ball mill jar. Ball mill at 400 r / min for 12 h. After ball milling, place the mixture in an oven at 90℃ for 8 h to dry, then place it back in the ball mill jar, with approximately 30 balls, and ball mill at 500 r / min for 10 min to obtain a mixed powder.

[0061] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of approximately 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950°C at a rate of 5°C / min and held at that temperature for 14 days. Then, the temperature is lowered to 500°C at a rate of 5°C / min to shut down the process, and the furnace is allowed to cool naturally to room temperature, yielding the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba1Sr2Co. 1.25 Cu 0.75 Fe 24 O 41 .

[0062] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0063] Example 5: The chemical formula of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material in this example is Ba. 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The preparation method differs from Example 1 in that steps one and seven are replaced by the following operations:

[0064] Step one is as follows: Press the Z-type hexagonal ferrite Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41The stoichiometric ratio of 3.5520 g BaCO3, 3.9859 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 was weighed out and placed in a ball mill jar. 140 mL of 95% ethanol was added, and the number of balls in the ball mill jar was approximately 30. The mixture was ball milled at 400 r / min for 12 h. After ball milling, the mixture was placed in an oven at 90 °C for 8 h to dry. After drying, the mixture was placed back into the ball mill jar, and the number of balls in the ball mill jar was approximately 30. The mixture was ball milled at 500 r / min for 10 min to obtain a mixed powder.

[0065] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba. 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0066] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0067] Example 6: The chemical formula of the Z-type hexagonal ferrite magnetoelectric coupling ceramic material in this example is Ba. 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The preparation method differs from Example 1 in that steps one and seven are replaced by the following operations:

[0068] Step one is as follows: Press the Z-type hexagonal ferrite Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41The stoichiometric ratio of 4.1440 g BaCO3, 3.5431 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 was weighed out and placed in a ball mill jar. 140 mL of 95% ethanol was added, with approximately 30 balls in the jar. The mixture was ball-milled at 400 r / min for 12 h. After ball milling, the mixture was dried in an oven at 90℃ for 8 h. After drying, the mixture was placed back into the ball mill jar, with approximately 30 balls in the jar, and ball-milled at 500 r / min for 10 min to obtain a mixed powder.

[0069] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tubes at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite Ba annealed under an oxygen atmosphere. 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0070] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0071] Example 7: This example differs from Example 1 in that steps one and seven are replaced by the following operations:

[0072] Step one is as follows: Press the Z-type hexagonal ferrite Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The stoichiometric ratio of 4.4400 g BaCO3, 3.3217 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 was weighed out and placed in a ball mill jar. 140 mL of 95% ethanol was added, with approximately 30 balls in the jar. The mixture was ball-milled at 400 r / min for 12 h. After ball milling, the mixture was dried in an oven at 90 °C for 8 h. After drying, the mixture was placed back into the ball mill jar, with approximately 30 balls in the jar, and ball-milled at 500 r / min for 10 min to obtain a mixed powder.

[0073] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba. 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0074] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0075] Example 8: This example differs from Example 1 in that steps one and seven are replaced by the following operations:

[0076] Step one is as follows: Press the Z-type hexagonal ferrite Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The stoichiometric ratio of 4.7360 g BaCO3, 3.1002 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 was weighed out and placed in a ball mill jar. 140 mL of 95% ethanol was added, with approximately 30 balls in the jar. The mixture was ball-milled at 400 r / min for 12 h. After ball milling, the mixture was dried in an oven at 90℃ for 8 h. After drying, the mixture was placed back into the ball mill jar, with approximately 30 balls in the jar, and ball-milled at 500 r / min for 10 min to obtain a mixed powder.

[0077] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of approximately 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950°C at a rate of 5°C / min and held at that temperature for 14 days. Then, the temperature is lowered to 500°C at a rate of 5°C / min to shut down the process, and the furnace is allowed to cool naturally to room temperature, yielding the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba. 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0078] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0079] Example 9: This example differs from Example 1 in that steps one and seven are replaced by the following operations:

[0080] Step one is as follows: Press the Z-type hexagonal ferrite Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The stoichiometric ratio of 5.3280 g BaCO3, 2.6573 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 was weighed out and placed in a ball mill jar. 140 mL of 95% ethanol was added, and the number of balls in the ball mill jar was approximately 30. The mixture was ball milled at 400 r / min for 12 h. After ball milling, the mixture was placed in an oven at 90℃ for 8 h to dry. After drying, the mixture was placed back into the ball mill jar, and the number of balls in the ball mill jar was approximately 30. The mixture was ball milled at 500 r / min for 10 min to obtain a mixed powder.

[0081] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba. 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0082] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0083] Example 10: This example differs from Example 1 in that steps one and seven are replaced by the following operations:

[0084] Step one is as follows: Press the Z-type hexagonal ferrite Ba 2.2 Sr 0.8 Co 1.5 Cu 0.5 Fe 24 O 41The stoichiometric ratio of 6.5121 g BaCO3, 1.7715 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 was weighed out and placed in a ball mill jar. 140 mL of 95% ethanol was added, with approximately 30 balls in the jar. The mixture was ball-milled at 400 r / min for 12 h. After ball milling, the mixture was dried in an oven at 90℃ for 8 h. After drying, the mixture was placed back into the ball mill jar, with approximately 30 balls in the jar, and ball-milled at 500 r / min for 10 min to obtain a mixed powder.

[0085] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba. 2.2 Sr 0.8 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0086] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0087] Example 11: This example differs from Example 1 in that steps one and seven are replaced by the following operations:

[0088] Step one is as follows: Press the Z-type hexagonal ferrite Ba 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O 41 Weigh out 7.6961 g BaCO3, 0.8857 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 according to the stoichiometric ratio, place them in a ball mill jar, and add 140 mL of 95% ethanol. The number of balls in the ball mill jar should be approximately 30. Ball mill at 400 r / min for 12 h. After ball milling, place the mixture in an oven at 90℃ for 8 h to dry. After drying, place it back in the ball mill jar, with approximately 30 balls in the jar, and ball mill at 500 r / min for 10 min to obtain a mixed powder.

[0089] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba. 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O 41 .

[0090] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0091] Example 12: This example differs from Example 1 in that steps one and seven are replaced by the following operations:

[0092] Step one is as follows: Press the Z-type hexagonal ferrite Ba3Co 1.25 Cu 0.75 Fe 24 O 41 Weigh out 8.8801 g BaCO3, 0 g SrCO3, 1.5049 g Co3O4, 0.9155 g CuO, and 28.7438 g Fe2O3 according to the stoichiometric ratio, place them in a ball mill jar, and add 140 mL of 95% ethanol. The number of balls in the ball mill jar is approximately 30. Ball mill at 400 r / min for 12 h. After ball milling, place the mixture in an oven at 90℃ for 8 h to dry. After drying, place it back in the ball mill jar, with approximately 30 balls in the jar, and ball mill at 500 r / min for 10 min to obtain a mixed powder.

[0093] Step seven is performed as follows: The Z-shaped hexagonal ferrite sintered in the box furnace is placed into a tube furnace. Oxygen is introduced into the furnace tube at a flow rate of 100 mL / min to obtain an oxygen atmosphere. Simultaneously, the tube furnace is heated to 950℃ at a rate of 5℃ / min and held at that temperature for 14 days. Then, it is cooled to 500℃ at a rate of 5℃ / min to shut down the program, and then allowed to cool naturally to room temperature to obtain the Z-shaped hexagonal ferrite magnetoelectric coupling ceramic material Ba3Co. 1.25 Cu 0.75 Fe 24 O 41 .

[0094] The other steps and parameters in this embodiment are the same as in Embodiment 1.

[0095] Scanning electron microscopy (SEM) was performed on the Z-type hexagonal ferrites prepared in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12. Examples 1 to 12 (Sr3Co) were also examined. 1.25 Cu 0.75 Fe 24 O 41， Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.2 Sr 0.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O41， Ba3Co 1.25 Cu 0.75 Fe 24 O 41 Scanning electron microscope images such as Figure 1 As shown.

[0096] from Figure 1 It can be seen that the test sample exhibits a hexagonal plate-like structure, which conforms to the typical characteristics of Z-type hexagonal ferrite.

[0097] XRD analysis was performed on the Z-type hexagonal ferrites prepared in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12. The obtained XRD spectra are shown below. Figure 2 As shown, from Figure 2 It can be seen that Sr3Co 1.25 Cu 0.75 Fe 24 O 41， Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.8 Sr1.2 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.2 Sr 0.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba3Co 1.25 Cu 0.75 Fe 24 O 41 They all exhibit a characteristic Z-shaped hexagonal ferrite spatial configuration.

[0098] Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 of Sr3Co 1.25 Cu 0.75 Fe 24 O 41， Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.6 Sr1.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.2 Sr 0.8 Co 1.25 Cu 0.75 Fe 24 O 41， Ba 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O 41， Ba3Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric current induced by the magnetic field under positive and negative polarized electric fields obtained by the test is as follows: Figure 3-14 As shown.

[0099] from Figure 3 , Figure 12 , Figure 13 and Figure 14 It can be seen that the magnetoelectric coupling coefficients of Examples 1, 10, 11, and 12 are all 0, regardless of whether they are under a forward-polarized electric field or a reverse-polarized electric field. This indicates that Example 1 (Sr3Co) 1.25 Cu 0.75 Fe 24 O 41 Example 10 (Ba) 2.2 Sr 0.8 Co 1.25 Cu 0.75 Fe 24 O 41 Example 11 (Ba) 2.6 Sr 0.4 Co 1.25 Cu 0.75 Fe 24 O 41 Example 12 (Ba3Co) 1.25 Cu 0.75 Fe 24 O 41 Z-type hexagonal ferrites do not exhibit magnetoelectric coupling performance, whether at low temperatures or at room temperature and above.

[0100] from Figure 4As can be seen, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 It exhibits magnetoelectric coupling performance under both low temperature and room temperature and above conditions.

[0101] Under a positively polarized electric field, during the process of the swept field changing from 2 kOe to 0 and then to -2 kOe, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a shape symmetrical about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, by changing the direction of the sweep field, it is possible to achieve the desired effect on Example 2 (Ba). 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the sample's magnetoelectric coupling coefficient is controlled.

[0102] Under reverse polarization electric field conditions, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a symmetrical shape about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, under reverse polarization electric field conditions, the direction of the sweep field can be changed to achieve the desired effect on the sample (Ba). 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The control of the sample's magnetoelectric coupling coefficient.

[0103] In summary, under both forward and reverse polarization electric fields, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The variation of the magnetoelectric coupling coefficient of the sample with the scanned field reveals that, under the same scanned field conditions, the coefficients of the sample in Example 2 (Ba) vary with different polarization electric fields. 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The directions of the magnetoelectric coupling coefficients of the samples are opposite. (Based on Example 2 (Ba)) 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature of the sample shows that Example 2 (Ba) 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature reaches 320K, breaking through the performance limitations of magnetoelectric coupling under room temperature conditions. Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample under low-temperature conditions reached a maximum of 0.12 mV / cm Oe.

[0104] Therefore, Example 2 (Ba 0.2 Sr 2.8 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling coefficient of the sample can be modulated by the direction of the applied sweep field and the direction of the pre-polarized electric field. This has potential application advantages in the field of non-volatile memory based on magnetoelectric coupling devices.

[0105] from Figure 5 As can be seen, Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 It exhibits magnetoelectric coupling performance under both low temperature and room temperature and above conditions.

[0106] Under a positively polarized electric field, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a shape symmetrical about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, by changing the direction of the sweep field, it is possible to achieve the desired effect on Example 3 (Ba). 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the sample's magnetoelectric coupling coefficient is controlled.

[0107] Under reverse polarization electric field conditions, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 3 (Ba0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a symmetrical shape about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, under reverse polarization electric field conditions, the direction of the sweep field can be changed to achieve the desired effect on the sample (Ba). 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The control of the sample's magnetoelectric coupling coefficient.

[0108] In summary, under both forward and reverse polarization electric fields, Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The variation of the magnetoelectric coupling coefficient of the sample with the scanned field reveals that, under the same scanned field conditions, the coefficients of the sample in Example 3 (Ba) vary with different polarization electric fields. 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The directions of the magnetoelectric coupling coefficients of the sample are opposite.

[0109] Therefore, Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41The magnetoelectric coupling coefficient of the sample can be modulated by the direction of the applied sweep field and the direction of the pre-polarized electric field. This has potential application advantages in the field of non-volatile memory based on magnetoelectric coupling. Through Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature of the sample shows that, in Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature reaches 350K, breaking through the performance limitations of magnetoelectric coupling under room temperature conditions. Example 3 (Ba 0.6 Sr 2.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample under low-temperature conditions reached a maximum of 4.11 mV / cm Oe.

[0110] from Figure 6 As can be seen, Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 It exhibits magnetoelectric coupling performance under both low temperature and room temperature and above conditions.

[0111] Under a positively polarized electric field, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a shape symmetrical about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 4 (Ba 1.0 Sr 2.0 Co1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, by changing the direction of the sweep field, it is possible to achieve the desired effect on Example 4 (Ba). 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the sample's magnetoelectric coupling coefficient is controlled.

[0112] Under reverse polarization electric field conditions, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a symmetrical shape about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, under reverse polarization electric field conditions, the direction of the sweep field can be changed to achieve the desired effect on the sample (Ba). 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The control of the sample's magnetoelectric coupling coefficient.

[0113] In summary, the variation of the magnetoelectric coupling coefficient of the sample with the scanned field under both forward and reverse polarization electric fields reveals that, under the same scanned field conditions, the magnetoelectric coupling coefficient of Example 4 (Ba) varies with the scanned field conditions under different polarization electric fields. 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The directions of the magnetoelectric coupling coefficients of the sample are opposite.

[0114] Therefore, Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling coefficient of the sample can be modulated by the direction of the applied sweep field and the direction of the pre-polarized electric field. This has potential application advantages in the field of non-volatile memory based on magnetoelectric coupling. Through Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature of the sample shows that, in Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature reaches 330K, breaking through the performance limitations of magnetoelectric coupling under room temperature conditions. Example 4 (Ba 1.0 Sr 2.0 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample under low-temperature conditions reached a maximum of 4.84 mV / cm Oe.

[0115] from Figure 7 As can be seen, Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 It exhibits magnetoelectric coupling performance under both low temperature and room temperature and above conditions.

[0116] Under a positively polarized electric field, during the process of the swept field changing from 2 kOe to 0 and then to -2 kOe, Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a shape symmetrical about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, by changing the direction of the sweep field, it is possible to achieve the desired effect on Example 5 (Ba). 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the sample's magnetoelectric coupling coefficient is controlled.

[0117] Under reverse polarization electric field conditions, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a symmetrical shape about the origin (0, 0); similarly, during the sweep field change from -2kOe to 0 and then back to 2kOe, Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, under reverse polarization electric field conditions, the direction of the sweep field can be changed to achieve the desired effect on the sample (Ba). 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The control of the sample's magnetoelectric coupling coefficient.

[0118] In summary, under both forward and reverse polarization electric fields, Example 5 (Ba 1.2 Sr 1.8 Co1.25 Cu 0.75 Fe 24 O 41 The variation of the magnetoelectric coupling coefficient of the sample with the scanned field reveals that, under the same scanned field conditions, the coefficients of the sample in Example 5 (Ba) vary with different polarization electric fields. 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The directions of the magnetoelectric coupling coefficients of the sample are opposite.

[0119] Therefore, Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling coefficient of the sample can be modulated by the direction of the applied sweep field and the direction of the pre-polarized electric field. This has potential application advantages in the field of non-volatile memory based on magnetoelectric coupling. Through Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature of the sample shows that, in Example 5 (Ba 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature reaches 330K, breaking through the performance limitations of magnetoelectric coupling under room temperature conditions. Example 5 (Ba) 1.2 Sr 1.8 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample under low-temperature conditions reached a maximum of 5.07 mV / cm Oe.

[0120] from Figure 8 As can be seen, Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 It exhibits magnetoelectric coupling performance under both low temperature and room temperature and above conditions.

[0121] Under a positively polarized electric field, during the process of the swept field changing from 2 kOe to 0 and then to -2 kOe, Example 6 (Ba1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a shape symmetrical about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, by changing the direction of the sweep field, it is possible to achieve the desired effect on Example 6 (Ba). 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the sample's magnetoelectric coupling coefficient is controlled.

[0122] Under reverse polarization electric field conditions, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a symmetrical shape about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, under reverse polarization electric field conditions, the direction of the sweep field can be changed to achieve the desired effect on the sample (Ba). 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The control of the sample's magnetoelectric coupling coefficient.

[0123] In summary, under both forward and reverse polarization electric fields, Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The variation of the magnetoelectric coupling coefficient of the sample with the scanned field reveals that, under the same scanned field conditions, the coefficients of the sample in Example 6 (Ba) vary with different polarization electric fields. 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The directions of the magnetoelectric coupling coefficients of the sample are opposite.

[0124] Therefore, Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling coefficient of the sample can be modulated by the direction of the applied sweep field and the direction of the pre-polarized electric field. This has potential application advantages in the field of non-volatile memory based on magnetoelectric coupling. Through Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature of the sample shows that Example 6 (Ba 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling tolerance temperature of the sample failed to exceed room temperature, indicating that it did not exhibit magnetoelectric coupling performance at room temperature. Example 6 (Ba) 1.4 Sr 1.6 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample under low-temperature conditions reached a maximum of 5.29 mV / cm Oe.

[0125] from Figure 9 As can be seen, Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 It exhibits magnetoelectric coupling performance under both low temperature and room temperature and above conditions.

[0126] Under a positively polarized electric field, during the process of the swept field changing from 2 kOe to 0 and then to -2 kOe, Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a shape symmetrical about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, by changing the direction of the sweep field, it is possible to achieve the desired effect on Example 7 (Ba). 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the sample's magnetoelectric coupling coefficient is controlled.

[0127] Under reverse polarization electric field conditions, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a symmetrical shape about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 7 (Ba 1.5 Sr1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, under reverse polarization electric field conditions, the direction of the sweep field can be changed to achieve the desired effect on the sample (Ba). 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The control of the sample's magnetoelectric coupling coefficient.

[0128] In summary, under both forward and reverse polarization electric fields, Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The change in magnetoelectric coupling coefficient with the swept field reveals that, under the same swept field conditions, the coefficient varies with different polarization electric field conditions. Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The directions of the magnetoelectric coupling coefficients of the sample are opposite.

[0129] Therefore, Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling coefficient of the sample can be modulated by the direction of the applied sweep field and the direction of the pre-polarized electric field. This has potential application advantages in the field of non-volatile memory based on magnetoelectric coupling. Through Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature of the sample shows that, in Example 7 (Ba 1.5 Sr 1.5 Co 1.25 Cu0.75 Fe 24 O 41 The magnetoelectric coupling tolerance temperature of the sample failed to exceed room temperature, indicating that it did not exhibit magnetoelectric coupling performance at room temperature. Example 7 (Ba) 1.5 Sr 1.5 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample under low-temperature conditions reached a maximum of 9.13 mV / cm Oe.

[0130] from Figure 10 As can be seen, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 It exhibits magnetoelectric coupling performance under both low temperature and room temperature and above conditions.

[0131] Under a positively polarized electric field, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a shape symmetrical about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, by changing the direction of the sweep field, it is possible to achieve the desired effect on Example 8 (Ba). 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the sample's magnetoelectric coupling coefficient is controlled.

[0132] Under reverse polarization electric field conditions, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a symmetrical shape about the origin (0, 0); similarly, during the sweep field change from -2kOe to 0 and then back to 2kOe, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, under reverse polarization electric field conditions, the direction of the sweep field can be changed to achieve the desired effect on the sample (Ba). 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The control of the sample's magnetoelectric coupling coefficient.

[0133] In summary, under both forward and reverse polarization electric fields, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The variation of the magnetoelectric coupling coefficient of the sample with the scanned field reveals that, under the same scanned field conditions, the coefficients of the sample in Example 8 (Ba) vary with different polarization electric fields. 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The directions of the magnetoelectric coupling coefficients of the sample are opposite.

[0134] Therefore, Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41The magnetoelectric coupling coefficient of the sample can be modulated by the direction of the applied sweep field and the direction of the pre-polarized electric field. This has potential application advantages in the field of non-volatile memory based on magnetoelectric coupling. Through Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature of the sample shows that, in Example 8 (Ba 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling tolerance temperature of Example 8 (Ba) failed to exceed room temperature, indicating that it does not exhibit magnetoelectric coupling performance at room temperature. 1.6 Sr 1.4 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample under low-temperature conditions reached a maximum of 7.2 mV / cm Oe.

[0135] from Figure 11 As can be seen, Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 It exhibits magnetoelectric coupling performance under both low temperature and room temperature and above conditions.

[0136] Under a positively polarized electric field, during the process of the swept field changing from 2 kOe to 0 and then to -2 kOe, Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a shape symmetrical about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 9 (Ba 1.8 Sr 1.2 Co1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, by changing the direction of the sweep field, it is possible to achieve the desired effect on Example 9 (Ba). 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the sample's magnetoelectric coupling coefficient is controlled.

[0137] Under reverse polarization electric field conditions, during the process of the swept field changing from 2kOe to 0 and then to -2kOe, Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample exhibits a symmetrical shape about the origin (0, 0); similarly, during the process of the swept field changing from -2kOe to 0 and then back to 2kOe, Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample also exhibits a symmetrical shape about the origin (0, 0); the difference is that when the sweep direction changes, Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The direction of the magnetoelectric coupling coefficient of the sample changes, therefore, under reverse polarization electric field conditions, the direction of the sweep field can be changed to achieve the desired effect on the sample (Ba). 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The modulation of the magnetoelectric coupling coefficient of the product.

[0138] In summary, under both forward and reverse polarization electric fields, Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The variation of the magnetoelectric coupling coefficient of the sample with the scanned field reveals that, under the same scanned field conditions, the coefficients of the sample in Example 9 (Ba) vary with different polarization electric fields. 1.8 Sr1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The directions of the magnetoelectric coupling coefficients of the sample are opposite.

[0139] Therefore, Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling coefficient of the sample can be modulated by the direction of the applied sweep field and the direction of the pre-polarized electric field. This has potential application advantages in the field of non-volatile memory based on magnetoelectric coupling. Through Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling withstand temperature of the sample shows that Example 9 (Ba 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The magnetoelectric coupling tolerance temperature of Example 9 (Ba) failed to exceed room temperature, indicating that it does not exhibit magnetoelectric coupling performance at room temperature. 1.8 Sr 1.2 Co 1.25 Cu 0.75 Fe 24 O 41 The dynamic magnetoelectric coupling coefficient of the sample under low-temperature conditions reached a maximum of 4.45 mV / cm Oe.

[0140] In summary, by controlling the Ba / Sr ratio in Z-type hexagonal ferrite, it is possible to not only regulate the magnetoelectric coupling coefficient of the sample but also effectively control its magnetoelectric coupling tolerance temperature. In this study, the Ba-doped samples exhibited dynamic magnetoelectric coupling performance in the 0.2–1.8 composition range. In particular, the samples with Ba doping in the 0.2–1 range demonstrated dynamic magnetoelectric coupling performance with a tolerance temperature exceeding room temperature, reaching a maximum of 350 K, indicating potential advantages in the field of magnetoelectric coupling. The dynamic magnetoelectric coupling coefficients of the implemented samples under low-temperature conditions are shown in Table 1.

[0141] Table 1 Dynamic magnetoelectric coupling performance of Z-type hexagonal ferrites

[0142]

[0143]

[0144] Testing of the dynamic magnetoelectric coupling performance of the prototypes revealed that when the ratio of introduced Ba to Sr was 1:1, the prototype exhibited the highest dynamic magnetoelectric coupling coefficient of 9.13 mV / cm Oe, demonstrating potential advantages in the field of magnetoelectric coupling. When the introduced Ba content was between 0.2% and 1.8%, the sample exhibited excellent magnetoelectric coupling performance at low temperatures, and the direction of the dynamic magnetoelectric coupling performance could be controlled by adjusting the direction of the pre-polarized electric field. When the introduced Ba content was between 0.2% and 1%, the magnetoelectric coupling tolerance temperature of the prototypes exceeded room temperature, demonstrating potential advantages in practical applications of magnetoelectric coupling.

[0145] The specific embodiments of the present invention have been described above. It should be noted that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A Z-type hexagonal ferrite magnetoelectric coupling ceramic material, characterized in that, Its chemical formula is Ba x Sr 3- x Co 1.25 Cu 0.75 Fe 24 O 41 Where, 0.2≤ x ≤1.0; is prepared by preparing Z-type hexagonal ferrite from BaCO3, SrCO3, Co3O4, CuO and Fe2O3, placing it in a tube furnace, heating the tube furnace to 950℃ at a rate of 5℃ / min under an oxygen atmosphere and holding it at that temperature for 14 days, then cooling it to 500℃ at a rate of 5℃ / min, and finally allowing it to cool naturally to room temperature.

2. The magnetoelectric coupling ceramic material according to claim 1, characterized in that, x =0.2、0.6、1.0。 3. The magnetoelectric coupling ceramic material according to claim 1, characterized in that, The magnetoelectric coupling performance of the magnetoelectric coupling ceramic material is resistant to temperatures of 300K~350K.

4. The method for preparing the magnetoelectric coupled ceramic material according to any one of claims 1-3, characterized in that, Includes the following steps:

1. Weigh BaCO3, SrCO3, Co3O4, CuO and Fe2O3 according to their chemical formulas, perform wet ball milling together, then dry them and perform dry ball milling.

2. Pre-sintering: First, heat to 1000 ℃ at a rate of 5 ℃ / min and hold for 10 h, then cool to 500 ℃ at a rate of 5 ℃ / min, and then cool naturally to room temperature to obtain pre-sintered powder; 3. After wet ball milling the pre-calcined powder, dry it and then dry ball mill it. Fourth, add polyvinyl alcohol solution dropwise, grind evenly, sieve, and press into sheets to obtain block green bodies; 5. Remove the glue from the block-shaped blank; VI. Then sintering in an oxygen atmosphere: heat up to 1000 ℃ at a rate of 5 ℃ / min, then heat up to 1100 ℃-1140 ℃ at a rate of 2 ℃ / min and hold for 10 h, then cool down to 1000 ℃ at a rate of 2 ℃ / min, then cool down to 500 ℃ at a rate of 5 ℃ / min and cool naturally to room temperature to obtain Z-type hexagonal ferrite; 7. Place the Z-type hexagonal ferrite obtained in step 6 into a tube furnace. Under an oxygen atmosphere, heat the tube furnace to 950°C at a rate of 5°C / min and hold for 14 days. Then, cool it down to 500°C at a rate of 5°C / min and allow it to cool naturally to room temperature to obtain the Z-type hexagonal ferrite magnetoelectric coupling ceramic material.

5. The method according to claim 4, characterized in that, In step one, wet ball milling uses 95% (volume) ethanol as the ball milling medium and ball mills at a speed of 400 r / min for 12 h; drying is carried out at 90℃ for 8 h; dry ball milling is carried out at a speed of 500 r / min for 10 min.

6. The method according to claim 4, characterized in that, In step four, the mass concentration of the polyvinyl alcohol solution is 5%; the material is added at a ratio of 5 g of solid to 10 drops of polyvinyl alcohol solution.

7. The method according to claim 4, characterized in that, In step four, the tablet is pressed at a pressure of 6 MPa.

8. The method according to claim 4, characterized in that, In step five, the adhesive is removed by maintaining the temperature at 500 ℃ for 10 hours.

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