CN109336586B - BFO-ReFeO3-PZT multiferroic solid solution and method for preparing the same - Google Patents

Abstract

The invention relates to the technical field of preparation of multiferroic solid solutions, and provides a BFO-ReFeO ₃ -PZT multiferroic solid solution and a preparation method thereof. The chemical composition of the multiferroic solid solution is expressed as 0.5BiFeO ₃ -0.2ReFeO ₃ -0.3Pb( Zr _0.52 Ti _0.48 )FeO ₃ . The preparation method comprises: preparing BiFeO ₃ powder; preparing ReFeO ₃ powder; preparing Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder; mixing the above three powders through ball milling, drying, sieving, granulation, blanking and sintering to obtain BFO ‑ReFeO ₃ ‑PZT multiferroic solid solution. The BFO‑ReFeO ₃ ‑PZT multiferroic solid solution has high remanent polarization, remanent magnetization and strong magneto-dielectric effect, and its remanent polarization is in the range of greater than or equal to 0.9 μC/cm ² and less than or equal to 2.5 The range of μC/cm ² and its remanent magnetization is greater than or equal to 0.025 emu/g and less than or equal to 0.21 emu/g, and the maximum magnetic permittivity can be 16.1%.

Description

BFO-ReFeO3-PZT multiferroic solid solution and preparation method thereof

technical field

The invention relates to the technical field of multiferroic solid solutions, and in particular provides a BFO-ReFeO ₃ -PZT multiferroic solid solution and a preparation method thereof.

Background technique

The phenomenon that the dielectric properties of materials change with the change of the magnetic field is called the "magneto-dielectric effect". Materials with this effect have potential applications in resonant capacitors and capacitive read heads for data storage. A large magneto-dielectric effect means that a large change in permittivity or capacitance can be obtained with a small magnetic field. Since there is a certain relationship between the magnetoelectric effect and the magneto-dielectric effect of materials, materials with strong magneto-electric effect may exhibit a large magneto-dielectric effect. On the other hand, multiferroic materials generally exhibit strong magnetoelectric effects. Therefore, it is possible to find large magneto-dielectric effects in multiferroic materials with strong magnetoelectric coupling.

Among them, BFO (BiFeO ₃ ) is the only multiferroic material with high Curie temperature (T _c ~ 1103K) and high Neal temperature (T _N ~ 643K) at the same time, and theoretically has a strong magnetoelectric coupling effect. However, BFO is an antiferromagnetic material, and its magnetization is difficult, and its magneto-dielectric effect is only about 1.1%, which limits its application value. In order to improve the magneto-dielectric effect of BFO, its magnetic and electromechanical coupling properties need to be improved. ReFeO ₃ (Re=La, Y, Dy, Gd, Ho) is called rare earth iron oxide, which is a typical antiferromagnetic material, and the interface effect formed by it and BFO can improve the magnetic properties. Meanwhile, PZT (Pb(Zr _0.52 Ti _0.48 )FeO ₃ ), as a piezoelectric material with excellent performance, has high electromechanical coupling properties. However, there is currently a lack of preparation methods for solid-dissolving ReFeO3 and PZT in BFO to significantly improve the magnetic and electromechanical coupling properties of BFO and to produce a strong magneto-dielectric effect.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a BFO-ReFeO ₃ -PZT multiferroic solid solution, which aims to solve the lack of solid solution of ReFeO ₃ and PZT in BFO in the prior art to significantly improve the magnetic and electromechanical coupling characteristics of BFO, and The problem of producing a strong magneto-dielectric effect.

For achieving the above object, the technical scheme adopted in the present invention is:

In the first aspect, the chemical composition of the BFO-ReFeO ₃ -PZT multiferroic solid solution is expressed as 0.5BiFeO ₃ -0.2ReFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ , BiFeO ₃ :ReFeO ₃ :Pb(Zr _0.52 Ti _0.48 ) ) The stoichiometric ratio of FeO ₃ is 5:2:3, wherein Re is any one of La, Y, Dy, Gd and Ho.

In the second aspect, the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution, the chemical composition of the BFO-ReFeO ₃ -PZT multiferroic solid solution is expressed as 0.5BiFeO ₃ -0.2ReFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ , the steps of the preparation method are as follows:

Step 1: Weigh Bi ₂ O ₃ and Fe ₂ O according to the mass ratio of chemical formula BiFeO ₃ , and pass the weighed Bi ₂ O ₃ and Fe ₂ O through ball milling, drying, sieving, pre-burning, and secondary BiFeO ₃ powder is obtained after ball milling, secondary drying and secondary sieving;

Step 2, weigh Re ₂ O ₃ and Fe ₂ O ₃ according to the mass ratio of chemical formula ReFeO ₃ , pass the weighed Re ₂ O ₃ and Fe ₂ O ₃ through ball milling, drying, sieving, pre-burning, _ReFeO powder is obtained after secondary ball milling, secondary drying and secondary sieving;

Step 3: Weigh PbO, ZrO ₂ and TiO ₂ according to the mass ratio of chemical formula Pb(Zr _0.52 Ti _0.48 )FeO ₃ , and pass the weighed PbO, ZrO ₂ and TiO ₂ through ball milling, drying and sieving. , pre-sintering, secondary ball milling, secondary drying and secondary sieving to obtain Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder;

Step 4, according to the chemical formula 0.5BiFeO ₃ -0.2ReFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ stoichiometric ratio, respectively weigh the BiFeO ₃ powder, ReFeO ₃ powder and Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder Stir well to form a mixed powder, and the mixed powder is subjected to ball milling, drying, sieving, granulation, compacting and sintering to obtain a BFO-ReFeO ₃ -PZT multiferroic solid solution.

Specifically, in step 1, the ball milling time of one ball milling is less than or equal to 7h and more than or equal to 5h; the temperature of one drying is less than or equal to 100°C and more than or equal to 80°C, and the time of one drying is less than or equal to 7h and more than or equal to 5h; The particle size is less than or equal to 100 mesh and more than or equal to 70 mesh; the pre-sintering temperature is less than or equal to 800 ℃ and greater than or equal to 700 ℃ and the pre-sintering time is less than or equal to 1.5h and more than or equal to 2.5h; the ball milling time of the secondary ball milling is less than or equal to 7h and more than or equal to 5h; The temperature of the primary drying is less than or equal to 100°C and greater than or equal to 80°C and the time of the secondary drying is less than or equal to 1h and greater than or equal to 2h; the particle size of the secondary sieving is less than or equal to 150 mesh and greater than or equal to 100 mesh.

Specifically, in step 2, the ball milling time of one ball milling is less than or equal to 7h and more than or equal to 5h; the temperature of one drying is less than or equal to 100°C and greater than or equal to 80°C and the time of one drying is less than or equal to 7h and more than or equal to 5h; The particle size is less than or equal to 100 mesh and greater than or equal to 70 mesh; the pre-sintering temperature is less than or equal to 900 ℃ and greater than or equal to 800 ℃ and the pre-sintering time is less than or equal to 6h and greater than or equal to 4h; the ball milling time of the secondary ball milling is less than or equal to 7h and greater than or equal to 5h; The drying temperature is less than or equal to 100°C and greater than or equal to 80°C and the secondary drying time is less than or equal to 1h and greater than or equal to 2h; the particle size of the secondary sieving is less than or equal to 150 mesh and greater than or equal to 100 mesh.

Specifically, in step 2, Re is any one of La, Y, Dy, Gd and Ho.

Specifically, in step 3, the ball milling time of one ball milling is less than or equal to 7h and more than or equal to 5h; the temperature of one drying is less than or equal to 100°C and greater than or equal to 80°C and the time of one drying is less than or equal to 7h and more than or equal to 5h; The particle size is less than or equal to 100 mesh and greater than or equal to 70 mesh; the pre-sintering temperature is less than or equal to 950°C and greater than or equal to 850°C and the pre-sintering time is less than or equal to 1.5h and greater than or equal to 2.5h; the ball milling time of the secondary ball milling is less than or equal to 7h and greater than or equal to 5h; The temperature of the primary drying is less than or equal to 100°C and greater than or equal to 80°C and the time of the secondary drying is less than or equal to 1h and greater than or equal to 2h; the particle size of the secondary sieving is less than or equal to 150 mesh and greater than or equal to 100 mesh.

Specifically, in step 4, the time of ball milling is less than or equal to 7h and more than or equal to 5h; the drying temperature is less than or equal to 100°C and more than or equal to 80°C and the drying time is less than or equal to 14h and more than or equal to 10h; the particle size of sieving is less than or equal to 100 mesh and more than Equal to 70 mesh.

Specifically, in step 4, the granulation process is as follows: add polyvinyl alcohol with a concentration of 5-10 wt% to the mixed powder, grind uniformly, and then sieve to obtain granular powder.

Specifically, in step 4, the process of making the compact is as follows: the granular powder is pressed into a cake-shaped green compact under a pressure of 30-50 MPa.

Specifically, in step 4, the sintering process is as follows: in the degumming period, the temperature is raised to 500-600°C at a heating rate of 180-220°C/h, and kept for 20-40 minutes; in the calcination period, the temperature is 2-15°C/min The heating rate is increased to 1000-1100 °C, and the temperature is kept for 1.5-3 hours; in the cooling period, after the sintering is completed, air-cooled to room temperature.

The beneficial effects of the present invention: the BFO-ReFeO ₃ -PZT multiferroic solid solution and the preparation method thereof of the present invention, the chemical composition of the BFO-ReFeO ₃ -PZT multiferroic solid solution is expressed as 0.5BiFeO ₃ -0.2ReFeO ₃ -0.3Pb (Zr _0.52 Ti _0.48 )FeO ₃ . The BFO-RFO-PZT ternary solid solution system is used, in which ReFeO ₃ is a rare earth iron oxide, which is a typical antiferromagnetic material. The interface effect formed by it and BFO improves the overall magnetic properties. As a piezoelectric material with excellent performance, PZT has high electromechanical coupling properties. The BFO-ReFeO ₃ -PZT multiferroic solid solution prepared by the preparation method provided in the embodiment of the present invention has high remanent polarization and remanent magnetization, and the remanent polarization range is greater than or equal to 0.9 μC/cm ² It is less than or equal to 2.5μC/cm ² and its remanent magnetization range is greater than or equal to 0.025emu/g and less than or equal to 0.21emu/g. At the same time, it has a strong magneto-dielectric effect, and the maximum magneto-dielectric coefficient can be 16.1%.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only for the present invention. In some embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without any creative effort.

Fig. 1 is the flow chart of the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided by the embodiment of the present invention;

Fig. 2 is the electroporation of 0.5BiFeO ₃ -0.2LaFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution obtained by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 1 of the present invention hysteresis loop diagram;

FIG. 3 is the magnetic properties of the 0.5BiFeO ₃ -0.2LaFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the method for preparing the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 1 of the present invention hysteresis loop diagram;

FIG. 4 is the magnetic properties of the 0.5BiFeO ₃ -0.2LaFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 1 of the present invention Dielectric effect diagram;

Fig. 5 is the electroporation of the 0.5BiFeO ₃ -0.2YFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution obtained by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the second embodiment of the present invention hysteresis loop diagram;

FIG. 6 is the magnetic properties of 0.5BiFeO ₃ -0.2YFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 2 of the present invention hysteresis loop diagram;

FIG. 7 is the magnetic properties of the 0.5BiFeO ₃ -0.2YFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ multiferroic solid solution prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the second embodiment of the present invention Dielectric effect diagram;

FIG. 8 is the electroporation of 0.5BiFeO ₃ -0.2DyFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 3 of the present invention hysteresis loop diagram;

FIG. 9 is the magnetic properties of 0.5BiFeO ₃ -0.2DyFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 3 of the present invention hysteresis loop diagram;

Fig. 10 is the magnetic properties of 0.5BiFeO ₃ -0.2DyFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 3 of the present invention Dielectric effect diagram;

11 is the hysteresis of 0.5BiFeO ₃ -0.2GdFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the fourth embodiment of the present invention return line graph;

Fig. 12 is the magnetic properties of the 0.5BiFeO ₃ -0.2GdFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 4 of the present invention hysteresis loop diagram;

Fig. 13 is the magnetic properties of 0.5BiFeO ₃ -0.2GdFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 4 of the present invention Dielectric effect diagram;

Fig. 14 is the electroporation of 0.5BiFeO ₃ -0.2HoFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution obtained by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 5 of the present invention hysteresis loop diagram;

Fig. 15 is the magnetic properties of the 0.5BiFeO ₃ -0.2HoFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ multiferroic solid solution prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 5 of the present invention hysteresis loop diagram;

FIG. 16 is the magnetic properties of 0.5BiFeO ₃ -0.2HoFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ multiferroic solid solution prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 5 of the present invention Dielectric effect diagram.

Detailed ways

The following describes in detail the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to explain the present invention and should not be construed as limiting the present invention.

Please refer to FIG. 1. FIG. 1 is a flow chart of a method for preparing a BFO-ReFeO ₃ -PZT multiferroic solid solution provided in an embodiment of the present invention. The chemical composition of the BFO-ReFeO ₃ -PZT multiferroic solid solution is represented as 0.5BiFeO ₃ - The stoichiometric ratio of 0.2ReFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 )FeO ₃ , BiFeO ₃ : ReFeO ₃ : Pb(Zr _0.52 Ti _0.48 )FeO ₃ is 5:2:3, wherein Re is La, Y, Dy, Either Gd or Ho.

The steps of the preparation method are as follows:

Step 1: Weigh Bi ₂ O ₃ and Fe ₂ O according to the mass ratio of chemical formula BiFeO ₃ , and pass the weighed Bi ₂ O ₃ and Fe ₂ O through ball milling, drying, sieving, pre-burning, and secondary BiFeO ₃ powder is obtained after ball milling, secondary drying and secondary sieving;

Step 2, weigh Re ₂ O ₃ and Fe ₂ O ₃ according to the mass ratio of chemical formula ReFeO ₃ , pass the weighed Re ₂ O ₃ and Fe ₂ O ₃ through ball milling, drying, sieving, pre-burning, _ReFeO powder is obtained after secondary ball milling, secondary drying and secondary sieving;

Step 3: Weigh PbO, ZrO ₂ and TiO ₂ according to the mass ratio of chemical formula Pb(Zr _0.52 Ti _0.48 )FeO ₃ , and pass the weighed PbO, ZrO ₂ and TiO ₂ through ball milling, drying and sieving. , pre-sintering, secondary ball milling, secondary drying and secondary sieving to obtain Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder;

Step 4, according to the chemical formula 0.5BiFeO ₃ -0.2ReFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ stoichiometric ratio, respectively weigh the BiFeO ₃ powder, ReFeO ₃ powder and Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder Stir well to form a mixed powder, and the mixed powder is subjected to ball milling, drying, sieving, granulation, compacting and sintering to obtain a BFO-ReFeO ₃ -PZT multiferroic solid solution.

The preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided by the embodiment of the present invention adopts the BFO-RFO-PZT ternary solid solution system, wherein ReFeO ₃ is a rare earth iron oxide, which is a typical antiferromagnetic material, Its interfacial effect with BFO improves the overall magnetic properties. As a piezoelectric material with excellent performance, PZT has high electromechanical coupling properties. The BFO-ReFeO ₃ -PZT multiferroic solid solution prepared by the preparation method provided in the embodiment of the present invention has high remanent polarization and remanent magnetization, and the remanent polarization range is greater than or equal to 0.9 μC/cm ² It is less than or equal to 2.5μC/cm ² and its remanent magnetization range is greater than or equal to 0.025emu/g and less than or equal to 0.21emu/g. At the same time, it has a strong magneto-dielectric effect, and the maximum magneto-dielectric coefficient can be 16.1%.

Example 1

Weigh Bi ₂ O ₃ and Fe ₂ O respectively according to the mass ratio of chemical formula BiFeO ₃ , add 100 ml of absolute ethanol to Bi ₂ O ₃ and Fe ₂ O for ball milling and mixing, and the time of one ball milling is 6h; take out the slurry after ball milling The material was kept in an oven at 90 °C for 6 hours; after drying, it was sieved, and the particle size of the first sieving was 80 mesh; the sieved powder was placed in an alumina crucible, and preheated at 750 °C in an air atmosphere. The pre-fired BiFeO _{3 powder was formed by firing for 2h; the pre-fired BiFeO 3 powder} was added to anhydrous ethanol again for secondary ball milling, and the secondary ball milling time was 6h. The slurry of the secondary ball milling was kept at 90° C. for 1.5 h, and then sieved for a second time, and the particle size of the secondary sieving was 120 meshes.

In this embodiment, Re is La rare earth element, and La ₂ O ₃ and Fe ₂ O ₃ are respectively weighed according to the mass ratio of chemical formula LaFeO ₃ , and absolute ethanol is added to La ₂ O ₃ and Fe ₂ O ₃ for ball milling and mixing , the time of one ball milling is 6h; the slurry after ball milling is taken out and kept in an oven at 90 ℃ for 6h; after drying, it is sieved, and the particle size of one sieving is 80 mesh; the sieved powder is put into alumina In the crucible, the pre-fired LaFeO _{3 powder was pre-fired at a temperature of 850 °C for 5 hours in an air atmosphere; the pre-fired LaFeO 3 powder} was added to anhydrous ethanol for secondary ball milling, and the secondary ball milling time was 6 hours; The slurry of the secondary ball milling is kept at 90° C. for 1.5 hours, and then sieved for a second time. The particle size of the secondary sieving is 120 meshes.

Weigh PbO, ZrO ₂ and TiO ₂ respectively according to the mass ratio of Pb(Zr _0.52 Ti _0.48 ) FeO ₃ , add 100 ml of absolute ethanol to PbO, ZrO ₂ and TiO ₂ for ball milling and mixing for 6 hours; take out the slurry after ball milling The material was kept in an oven at 90 °C for 6 hours; after drying, it was sieved, and the particle size of the first sieving was 80 mesh; Sintered for 2h to generate pre-sintered powder of Pb(Zr _0.52 Ti _0.48 )FeO ₃ ; the pre-sintered Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder was added to anhydrous ethanol again for secondary ball milling, and the time of secondary ball milling was 6h; The slurry of the secondary ball milling was kept at 90° C. for 1.5 h, and then sieved for a second time, and the particle size of the secondary sieving was 120 meshes.

According to the chemical formula 0.5BiFeO ₃ -0.2LaFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ stoichiometric ratio, respectively weigh the BiFeO ₃ powder, LaFeO ₃ powder and Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder and stir to form Mix the powder, add 100ml of absolute ethanol to the mixed powder for ball milling, the ball milling time is 6h; take out the mixed slurry and keep it in an oven at 90°C for 12h; after drying, sieve, and the sieved particle size is 80 mesh; add a polyvinyl alcohol aqueous solution with a concentration of 5wt% to the mixed powder after sieving as a bonding agent for ceramics, grind evenly, sieve and granulate to obtain granular powder; apply Press it into a green body with a diameter of 10 mm and a thickness of 1 mm at a pressure of 35 MPa; place the green body in a high-temperature furnace and heat it up to 550 °C at a heating rate of 200 °C/h, hold for 30 minutes for debinding, and then heat up at 10 °C/min The rate of heating was increased to 1025°C, the temperature was maintained for 2 hours, and finally cooled to room temperature with the furnace to obtain 0.5BiFeO ₃ -0.2LaFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ ceramic sheets.

Please refer to FIG. 2. FIG. 2 shows 0.5BiFeO ₃ -0.2LaFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ obtained by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the first embodiment of the present invention Hysteresis loop diagram of a ferrous solid solution. The hysteresis loop characterizes the change of the polarization of the sample in the alternating electric field, and it can reflect the remanent polarization of the sample. Generally, the larger the remanent polarization, the better the ferroelectricity of the sample. It can be seen from the figure that the remanent polarization of the multiferroic solid solution is 0.98 μC/cm2.

Please refer to FIG. 3. FIG. 3 shows 0.5BiFeO ₃ -0.2LaFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ obtained by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the first embodiment of the present invention Hysteresis loop diagram of a ferrous solid solution. The hysteresis loop characterizes the change of the magnetization of the sample in the alternating magnetic field, and it can reflect the residual magnetization. Generally, the larger the residual magnetization, the better the ferromagnetism of the sample. As can be seen from the figure, the remanent magnetization of the multiferroic solid solution is 0.025 emu/g.

Please refer to FIG. 4 . FIG. 4 shows 0.5BiFeO ₃ -0.2LaFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ obtained by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the first embodiment of the present invention Magneto-dielectric effect diagram of a ferrous solid solution. The magneto-dielectric effect characterizes the change of the dielectric constant of the sample in the magnetic field, which can reflect the coupling strength between the magnetic and electrical properties of the sample. A large magneto-dielectric effect means that a larger dielectric can be obtained with a smaller magnetic field. Changes in constants or capacitances are used in resonant capacitors and capacitive read heads for data storage. Generally, the sample has both ferroelectricity and ferromagnetism, so that the magneto-dielectric effect can be generated. It can be seen from the figure that the maximum magnetic permittivity of the multiferroic solid solution is 0.87%.

Embodiment 2

Weigh Bi ₂ O ₃ and Fe ₂ O respectively according to the mass ratio of chemical formula BiFeO ₃ , add 100ml of absolute ethanol to Bi ₂ O ₃ and Fe ₂ O for ball milling and mixing, and the time of one ball milling is 7h; take out the slurry after ball milling The powder was kept in an oven at 100 °C for 7 hours; after drying, it was sieved, and the particle size of the first sieving was 100 mesh; Sintered for 2.5h to generate pre-sintered powder of BiFeO ₃ ; the pre-sintered BiFeO ₃ powder was added with absolute ethanol again for secondary ball milling, and the time of secondary ball milling was 7h. The slurry of the secondary ball milling was kept at 100° C. for 2 h, and then sieved for a second time. The particle size of the secondary sieving was 150 meshes.

In this embodiment, Re is Y rare earth element, Y ₂ O ₃ and Fe ₂ O ₃ are respectively weighed according to the mass ratio of chemical formula YFeO ₃ , and 100 ml of absolute ethanol is added to Y ₂ O ₃ and Fe ₂ O ₃ for ball milling Mixing, the time of one ball milling is 7 hours; the slurry after ball milling is taken out and kept in an oven at 100 ° C for 7 hours; after drying, it is sieved, and the particle size of one sieving is 100 mesh; the sieved powder is put into oxidation In an aluminum crucible, pre-sintering at a temperature of 900°C for 6 hours in an air atmosphere generates a pre-sintered powder of YFeO ₃ ; add anhydrous ethanol to the pre-sintered YFeO ₃ powder again for secondary ball milling, and the secondary ball milling time is 7 hours; The slurry of the secondary ball milling was kept at 100° C. for 2 h, and then sieved for a second time. The particle size of the secondary sieving was 150 meshes.

Weigh PbO, ZrO ₂ and TiO ₂ respectively according to the mass ratio of Pb(Zr _0.52 Ti _0.48 ) FeO ₃ , add 100 ml of absolute ethanol to PbO, ZrO ₂ and TiO ₂ for ball milling and mixing for 7 hours; take out the ball-milled slurry The powder was kept in an oven at 100 °C for 7 hours; after drying, it was sieved, and the particle size of the first screening was 100 mesh; Sintered for 2.5h to generate the pre-sintered powder of Pb(Zr _0.52 Ti _0.48 )FeO ₃ ; the pre-sintered Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder was added to anhydrous ethanol again for secondary ball milling, and the secondary ball milling time was 7h ; The slurry of the second ball mill is kept at 100 ℃ for 2h, and then sieved for a second time, and the particle size of the second sieve is 150 mesh.

According to the chemical formula 0.5BiFeO ₃ -0.2YFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ stoichiometric ratio, respectively weigh the BiFeO ₃ powder, YFeO ₃ powder and Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder and stir to form To mix the powder, add 100ml of absolute ethanol to the mixed powder for ball milling, and the ball milling time is 7h; take out the mixed slurry and keep it in an oven at 100°C for 14h; after drying, sieve, and the sieved particle size is 100 mesh; add a polyvinyl alcohol aqueous solution with a concentration of 5wt% to the sieved mixed powder as a bonding agent for ceramics, grind evenly, sieve and granulate to obtain granular powder; apply 30MPa pressure, press it into a green body with a diameter of 10mm and a thickness of 1mm; place the green body in a high temperature furnace and heat it up to 500°C at a heating rate of 180°C/h, hold it for 20 minutes for degumming, and then heat up at 5°C/min The rate of heating was increased to 1055°C, the temperature was maintained for 2.5 hours, and finally cooled to room temperature with the furnace to obtain 0.5BiFeO ₃ -0.2YFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ ceramic sheets.

Please refer to FIG. 5 . FIG. 5 shows 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic obtained by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the second embodiment of the present invention Hysteresis loop diagram of a solid solution. It can be seen from the figure that the remanent polarization of the multiferroic solid solution is 2.09 μC/cm2.

Please refer to FIG. 6 . FIG. 6 shows 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic obtained by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the second embodiment of the present invention Hysteresis loop diagram of a solid solution. It can be seen from the figure that the remanent magnetization of the multiferroic solid solution is 0.209 emu/g.

Please refer to FIG. 7. FIG. 7 shows 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic obtained by the preparation method of the BBFO-ReFeO ₃ -PZT multiferroic solid solution provided in the second embodiment of the present invention A diagram of the magneto-dielectric effect of a solid solution. It can be seen from the figure that the maximum magnetic permittivity of the multiferroic solid solution is 6.67%.

Embodiment 3

Weigh Bi ₂ O ₃ and Fe ₂ O respectively according to the mass ratio of chemical formula BiFeO ₃ , add 100 ml of absolute ethanol to Bi ₂ O ₃ and Fe ₂ O for ball milling and mixing, and the time of one ball milling is 5h; take out the slurry after ball milling The powder was kept in an oven at 80 °C for 5 hours; after drying, it was sieved, and the particle size of the first sieving was 70 mesh; the sieved powder was placed in an alumina crucible, and pre-heated at a temperature of 700 °C in an air atmosphere. Sintered for 1.5h to generate pre-sintered powder of BiFeO ₃ ; add anhydrous ethanol to the pre-sintered BiFeO ₃ powder again for secondary ball milling, and the secondary ball milling time is 5h. The slurry of the secondary ball milling was kept at 80° C. for 1 hour, and then sieved for a second time, and the particle size of the secondary sieving was 100 meshes.

In this embodiment, Re is the rare earth element Dy, and Dy ₂ O ₃ and Fe ₂ O ₃ are weighed according to the mass ratio of the chemical formula DyFeO ₃ respectively, and 100 ml of anhydrous ethanol is added to the Dy ₂ O ₃ and Fe ₂ O ₃ for ball milling. Mixing, the time of one ball milling is 5 hours; the slurry after ball milling is taken out and kept in an oven at 80 °C for 5 hours; after drying, it is sieved, and the particle size of one sieving is 70 mesh; the sieved powder is put into oxidation In an aluminum crucible, pre-sintered at a temperature of 800 °C for 4 hours in an air atmosphere to generate pre-sintered powder of DyFeO ₃ ; add anhydrous ethanol to the pre-sintered DyFeO ₃ powder again for secondary ball milling, and the secondary ball milling time is 5 hours; The slurry of the secondary ball milling was kept at 80° C. for 1 hour, and then sieved for a second time, and the particle size of the secondary sieving was 100 meshes.

Weigh PbO, ZrO ₂ and TiO ₂ respectively according to the mass ratio of Pb(Zr _0.52 Ti _0.48 ) FeO ₃ , add 100 ml of absolute ethanol to PbO, ZrO ₂ and TiO ₂ for ball milling and mixing for 5 hours; take out the slurry after ball milling The material was kept in an oven at 80 °C for 5 hours; after drying, it was sieved, and the particle size of one sieving was 70 mesh; Sintered for 1.5h to generate pre-sintered powder of Pb(Zr _0.52 Ti _0.48 )FeO ₃ ; add the pre-sintered Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder again to anhydrous ethanol for secondary ball milling, and the secondary ball milling time is 5h ; The slurry of the secondary ball milling is kept at 80°C for 1 hour, and then sieved for a second time. The particle size of the secondary sieving is 100 meshes.

According to the chemical formula 0.5BiFeO ₃ -0.2DyFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ stoichiometric ratio, respectively weigh the BiFeO ₃ powder, DyFeO ₃ powder and Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder and stir to form To mix the powder, add 100ml of absolute ethanol to the mixed powder for ball milling, and the ball milling time is 5h; take out the mixed slurry and keep it in an oven at 80°C for 10h; after drying, sieve, and the sieved particle size is 70 mesh; add a polyvinyl alcohol aqueous solution with a concentration of 10wt% to the mixed powder after sieving as a bonding agent for ceramics, grind evenly, sieve and granulate to obtain granular powder; apply Press it into a green body with a diameter of 10mm and a thickness of 1mm at a pressure of 45MPa; place the green body in a high temperature furnace and heat it up to 600°C at a heating rate of 220°C/h, hold for 40min for debinding, and then heat up at 12°C/min The rate of heating was increased to 1000° C., the temperature was maintained for 2 hours, and finally cooled to room temperature with the furnace to obtain 0.5BiFeO ₃ -0.2DyFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ ceramic sheets.

Please refer to FIG. 8 . FIG. 8 shows 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic obtained by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the third embodiment of the present invention Hysteresis loop diagram of a solid solution. It can be seen from the figure that the remanent polarization of the multiferroic solid solution is 1.83 μC/cm2.

Please refer to FIG. 9. FIG. 9 shows 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic obtained by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 3 of the present invention Hysteresis loop diagram of a solid solution. It can be seen from the figure that the remanent magnetization of the multiferroic solid solution is 0.085 emu/g.

Please refer to FIG. 10 . FIG. 10 shows the 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the third embodiment of the present invention A diagram of the magneto-dielectric effect of a solid solution. It can be seen from the figure that the maximum magnetic permittivity of the multiferroic solid solution is 16.1%.

Embodiment 4

Weigh Bi ₂ O ₃ and Fe ₂ O respectively according to the mass ratio of chemical formula BiFeO ₃ , add 100 ml of absolute ethanol to Bi ₂ O ₃ and Fe ₂ O for ball milling and mixing, and the time of one ball milling is 6.5h; The slurry was kept in an oven at 95 °C for 5.5 hours; after drying, it was sieved, and the particle size of the first sieving was 90 mesh; the sieved powder was put into an alumina crucible, and the powder was placed in an air atmosphere at a temperature of 780 °C. Pre-sintering at a temperature of 2.5h generates pre-sintered powder of BiFeO ₃ ; the pre-sintered BiFeO ₃ powder is added to anhydrous ethanol again for secondary ball milling, and the time of secondary ball milling is 6.5 hours. The slurry of the secondary ball milling was kept at 85° C. for 1.5 hours, and then sieved for a second time. The particle size of the secondary sieving was 120 meshes.

In this embodiment, Re is a Gd rare earth element, and Gd ₂ O ₃ and Fe ₂ O ₃ are respectively weighed according to the mass ratio of chemical formula GdFeO ₃ , and 100 ml of absolute ethanol is added to Gd ₂ O ₃ and Fe ₂ O ₃ for ball milling. Mixing, the time of one ball milling is 6.5h; take out the ball-milled slurry and keep it in an oven at 95°C for 6.5h; sieve after drying, and the particle size of one sieve is 90 mesh; put the sieved powder into into an alumina crucible, and pre-sintered at 880°C for 5.5 hours in an air atmosphere to form pre-sintered GdFeO ₃ powder; add anhydrous ethanol to the pre-sintered GdFeO ₃ powder again for secondary ball milling, and the time for the secondary ball milling for 6.5h; the slurry of the secondary ball milling was kept at 95°C for 1.5h, and then sieved twice, and the particle size of the secondary sieving was 130 mesh.

Weigh PbO, ZrO ₂ and TiO ₂ respectively according to the mass ratio of Pb(Zr _0.52 Ti _0.48 ) FeO ₃ , add 100 ml of absolute ethanol to PbO, ZrO ₂ and TiO ₂ for ball milling and mixing for 5.5 hours; The slurry was kept in an oven at 85 °C for 5.5 hours; after drying, it was sieved, and the particle size of the first sieving was 80 mesh; Pre-sintering at temperature for 2h generates pre-sintered powder of Pb(Zr _0.52 Ti _0.48 )FeO ₃ ; the pre-sintered Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder is added to anhydrous ethanol again for secondary ball milling, and the time of secondary ball milling is 6.5h; keep the slurry of the secondary ball milling at 90°C for 1.5h, and then carry out a secondary sieving, and the particle size of the secondary sieving is 120 mesh.

According to the chemical formula 0.5BiFeO ₃ -0.2GdFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ stoichiometric ratio, respectively weigh the BiFeO ₃ powder, GdFeO ₃ powder and Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder and stir to form Mix the powder, add 100ml of absolute ethanol to the mixed powder for ball milling and mixing, the ball milling time is 5.5h; take out the mixed slurry and keep it in an oven at 95 ℃ for 13h; after drying, sieve, the sieved particle size It is 80 mesh; add a polyvinyl alcohol aqueous solution with a concentration of 8wt% to the mixed powder after sieving as a bonding agent for ceramics, grind evenly, sieve and granulate to obtain granular powder; Apply a pressure of 40MPa and press it into a green body with a diameter of 10mm and a thickness of 1mm; place the green body in a high temperature furnace and heat it up to 580°C at a heating rate of 190°C/h, hold for 35min for debinding, and then heat it at 15°C/min The heating rate was increased to 1000°C, kept for 2 hours, and finally cooled to room temperature with the furnace to obtain 0.5BiFeO ₃ -0.2GdFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ ceramic sheets.

Please refer to FIG. 11 . FIG. 11 is the 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the fourth embodiment of the present invention Hysteresis loop diagram of a solid solution. It can be seen from the figure that the remanent polarization of the multiferroic solid solution is 0.36 μC/cm2.

Please refer to FIG. 12. FIG. 12 shows the 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the fourth embodiment of the present invention Hysteresis loop diagram of a solid solution. As can be seen from the figure, the remanent magnetization of the multiferroic solid solution is 0.038 emu/g.

Please refer to FIG. 13 . FIG. 13 shows 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in Example 4 of the present invention A diagram of the magneto-dielectric effect of a solid solution. It can be seen from the figure that the maximum magnetic permittivity of the multiferroic solid solution is 3.39%.

Embodiment 5

Weigh Bi ₂ O ₃ and Fe ₂ O respectively according to the mass ratio of chemical formula BiFeO ₃ , add 100ml of absolute ethanol to Bi ₂ O ₃ and Fe ₂ O for ball milling and mixing, and the time of one ball milling is 5.5h; The slurry was kept in an oven at 85 °C for 6.5 hours; after drying, it was sieved, and the particle size of the first sieving was 80 mesh; the sieved powder was placed in an alumina crucible, and the sieved powder was placed in an air atmosphere at a temperature of 750 °C. The pre-sintered BiFeO _{3 powder is formed by pre-sintering for 2h at a temperature; the pre-sintered BiFeO 3 powder} is added to anhydrous ethanol again for secondary ball milling, and the secondary ball milling time is 5.5h. The slurry of the secondary ball milling was kept at 90° C. for 2 hours, and then sieved for a second time, and the particle size of the secondary sieving was 100 meshes.

In this embodiment, Re is the rare earth element Ho, and respectively weigh Ho ₂ O ₃ and Fe ₂ O ₃ according to the mass ratio of the chemical formula HoFeO ₃ , add 100 ml of absolute ethanol to Ho ₂ O ₃ and Fe ₂ O ₃ for ball milling Mixing, the time of one ball milling is 6.5h; take out the ball-milled slurry and keep it in an oven at 95°C for 6.5h; sieve after drying, and the particle size of one sieve is 90 mesh; put the sieved powder into Put it into an alumina crucible, and pre-sintered it in an air atmosphere at a temperature of 830 °C for 4 hours to generate HoFeO ₃ pre-sintered powder; add anhydrous ethanol to the pre-sintered HoFeO ₃ powder again for secondary ball milling, and the secondary ball milling time is 7h; keep the slurry of the secondary ball milling at 85° C. for 1 h, and then carry out secondary sieving, and the particle size of the secondary sieving is 150 mesh.

Weigh PbO, ZrO ₂ and TiO ₂ respectively according to the mass ratio of Pb(Zr _0.52 Ti _0.48 ) FeO ₃ , add 100 ml of absolute ethanol to PbO, ZrO ₂ and TiO ₂ for ball milling and mixing for 7 hours; take out the ball-milled slurry The powder was kept in an oven at 100 °C for 7 hours; after drying, it was sieved, and the particle size of the first screening was 100 mesh; Burn for 1.5h to generate pre-fired powder of Pb(Zr _0.52 Ti _0.48 )FeO ₃ ; add anhydrous ethanol to the pre-fired Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder again for secondary ball milling, and the secondary ball milling time is 7h ; The slurry of the secondary ball milling is kept at 90 ℃ for 1.5 hours, and then sieved for a second time, and the particle size of the secondary sieving is 150 mesh.

According to the chemical formula 0.5BiFeO ₃ -0.2HoFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ stoichiometric ratio, respectively weigh the BiFeO ₃ powder, HoFeO ₃ powder and Pb(Zr _0.52 Ti _0.48 ) FeO ₃ powder and stir to form To mix the powder, add 100ml of absolute ethanol to the mixed powder for ball milling, and the ball milling time is 7h; take out the mixed slurry and keep it in an oven at 100°C for 14h; after drying, sieve, and the sieved particle size is 100 mesh; add a polyvinyl alcohol aqueous solution with a concentration of 6wt% to the mixed powder after sieving as a bonding agent for ceramics, grind evenly, sieve and granulate to obtain granular powder; apply 30MPa pressure, press it into a green body with a diameter of 10mm and a thickness of 1mm; put the green body in a high-temperature furnace and heat it up to 530°C at a heating rate of 200°C/h, hold for 30min for debinding, and then heat up at 10°C/min The rate of heating was increased to 1100° C., the temperature was maintained for 3 hours, and finally cooled to room temperature with the furnace to obtain 0.5BiFeO ₃ -0.2HoFeO ₃ -0.3Pb(Zr _0.52 Ti _0.48 ) FeO ₃ ceramic sheets.

Please refer to FIG. 14 . FIG. 14 shows 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic prepared by the preparation method of BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the fifth embodiment of the present invention Hysteresis loop diagram of a solid solution. As can be seen from the figure, the remanent polarization of the multiferroic solid solution is 2.47 μC/cm2.

Please refer to FIG. 15. FIG. 15 is the 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the fifth embodiment of the present invention Hysteresis loop diagram of a solid solution. As can be seen from the figure, the remanent magnetization of the multiferroic solid solution is 0.084 emu/g.

Please refer to FIG. 16. FIG. 16 shows the 0.5BiFeO3-0.2LaFeO3-0.3Pb(Zr0.52Ti0.48)FeO3 multiferroic prepared by the preparation method of the BFO-ReFeO ₃ -PZT multiferroic solid solution provided in the fifth embodiment of the present invention A diagram of the magneto-dielectric effect of a solid solution. It can be seen from the figure that the maximum magnetic permittivity of the multiferroic solid solution is 5.57%.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (1)

1. BFO-ReFeO₃-PZT multiferroic solid solution, characterized in that the BFO-ReFeO is used in the production of a multiferroic solid solution₃Chemical composition of-PZT multiferroic solid solution expressed as 0.5BiFeO₃-0.2ReFeO₃-0.3Pb(Zr_0.52Ti_0.48)O₃The preparation method comprises the following steps:

step one, according to the chemical formula BiFeO₃Weighing Bi according to the mass ratio₂O₃And Fe₂O₃Weighing Bi₂O₃And Fe₂O₃The BiFeO is prepared by primary ball milling, primary drying, primary sieving, presintering, secondary ball milling, secondary drying and secondary sieving₃Powder;

step two, according to the chemical formula ReFeO₃Weighing Re according to the mass ratio of₂O₃And Fe₂O₃Weighing Re₂O₃And Fe₂O₃The ReFeO is prepared after primary ball milling, primary drying, primary sieving, pre-sintering, secondary ball milling, secondary drying and secondary sieving₃Powder;

step three, according to the chemical formula Pb (Zr)_0.52Ti_0.48)O₃Weighing PbO and ZrO according to the mass ratio₂And TiO₂Weighing PbO and ZrO₂And TiO₂Preparing Pb (Zr) through primary ball milling, primary drying, primary sieving, pre-sintering, secondary ball milling, secondary drying and secondary sieving_0.52Ti_0.48)O₃Powder;

step four, according to the chemical formula of 0.5BiFeO₃-0.2ReFeO₃-0.3Pb(Zr_0.52Ti_0.48)O₃Respectively weighing the BiFeO according to the stoichiometric ratio of 5:2:3₃Powder, ReFeO₃Powder and Pb (Zr)_0.52Ti_0.48)O₃The powder is stirred evenly to form mixed powder, and the mixed powder is subjected to ball milling, drying, sieving, granulation, blank making and sintering to obtain BFO-ReFeO₃-PZT multiferroic solid solution;

in the first step, the ball milling time of one-time ball milling is less than or equal to 7h and more than or equal to 5 h; the temperature of primary drying is less than or equal to 100 ℃ and more than or equal to 80 ℃, and the time of primary drying is less than or equal to 7h and more than or equal to 5 h; the granularity of the primary sieving is less than or equal to 100 meshes and more than or equal to 70 meshes; the pre-sintering temperature is less than or equal to 800 ℃ and more than or equal to 700 ℃ and the pre-sintering time is less than or equal to 1.5h and more than or equal to 2.5 h; the ball milling time of the secondary ball milling is less than or equal to 7 hours and more than or equal to 5 hours; the temperature of secondary drying is less than or equal to 100 ℃ and more than or equal to 80 ℃, and the time of secondary drying is less than or equal to 1h and more than or equal to 2 h; the granularity of the secondary sieving is less than or equal to 150 meshes and more than or equal to 100 meshes;

in the second step, the ball milling time of the primary ball milling is less than or equal to 7h and more than or equal to 5 h; the temperature of primary drying is less than or equal to 100 ℃ and is more than or equal to 80 ℃, and the time of primary drying is less than or equal to 7h and is more than or equal to 5 h; the granularity of the primary sieving is less than or equal to 100 meshes and more than or equal to 70 meshes; the pre-sintering temperature is less than or equal to 900 ℃ and more than or equal to 800 ℃, and the pre-sintering time is less than or equal to 6h and more than or equal to 4 h; the ball milling time of the secondary ball milling is less than or equal to 7 hours and more than or equal to 5 hours; the temperature of the secondary drying is less than or equal to 100 ℃ and more than or equal to 80 ℃, and the time of the secondary drying is less than or equal to 1h and more than or equal to 2 h; the granularity of the secondary sieving is less than or equal to 150 meshes and more than or equal to 100 meshes;

in the third step, the ball milling time of one ball milling is less than or equal to 7h and more than or equal to 5 h; the temperature of primary drying is less than or equal to 100 ℃ and more than or equal to 80 ℃, and the time of primary drying is less than or equal to 7h and more than or equal to 5 h; the granularity of the primary sieving is less than or equal to 100 meshes and more than or equal to 70 meshes; the pre-sintering temperature is less than or equal to 950 ℃ and more than or equal to 850 ℃, and the pre-sintering time is less than or equal to 1.5h and more than or equal to 2.5 h; the ball milling time of the secondary ball milling is less than or equal to 7 hours and more than or equal to 5 hours; the temperature of secondary drying is less than or equal to 100 ℃ and more than or equal to 80 ℃, and the time of secondary drying is less than or equal to 1h and more than or equal to 2 h; the granularity of the secondary sieving is less than or equal to 150 meshes and more than or equal to 100 meshes;

in the fourth step, the ball milling time is less than or equal to 7h and more than or equal to 5 h; the drying temperature is less than or equal to 100 ℃ and more than or equal to 80 ℃, and the drying time is less than or equal to 14h and more than or equal to 10 h; the screened granularity is less than or equal to 100 meshes and more than or equal to 70 meshes;

in the second step, Re is any one of La, Y, Dy, Gd and Ho;

in step four, the granulation process is as follows: adding 5-10 wt% of polyvinyl alcohol into the mixed powder, grinding uniformly, and sieving to obtain granular powder;

in the fourth step, the blank making process is as follows: pressing the granular powder into a cake-shaped green body under the pressure of 30-50 MPa;

in step four, the sintering process is as follows: in the glue discharging period, heating to 500-600 ℃ at the heating rate of 180-220 ℃/h, and preserving heat for 20-40 min; in the calcination period, the temperature is raised to 1000-1100 ℃ at the temperature rise rate of 2-15 ℃/min, and the temperature is kept for 1.5-3 h; and (5) cooling, namely air cooling to room temperature after sintering is finished.

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