Preparation method of YIG-M type barium ferrite mixed material for microstrip line circulator

Abstract

The invention relates to a preparation method of a YIG-M type barium ferrite mixed material for a microstrip line circulator. The preparation method comprises the following steps: firstly, preparing YIG precursor powder and barium ferrite powder; pressing the YIG precursor powder into a green body, and sintering to obtain phase-formed YIG ferrite; and crushing the YIG ferrite, mixing the crushed YIG ferrite with the barium ferrite precursor powder according to a mass ratio of 1: 2-2: 1, pressing the mixture into a green body, and carrying out sintering phase formation to obtain the YIG-M type barium ferrite mixed material. The external bias magnetic field of the prepared mixed material is far smaller than that of a traditional YIG material, a good circulation effect can be achieved only through a smaller permanent magnet, and a circulator can be further miniaturized and integrated.

Description

Technical Field

[0001] This invention belongs to the field of ferrite material technology, specifically relating to a method for preparing YIG-M type barium ferrite hybrid material for microstrip circulators. Background Technology

[0002] A circulator is a multi-port non-reciprocal microwave device whose fundamental characteristic is that electromagnetic waves can only propagate sequentially in a single direction. It is a core component of systems such as radar, communication base stations (including 5G / 6G), satellite communications, and microwave relays, used to isolate transmitted and received signals and protect sensitive power amplifiers from damage caused by reflected power. Microstrip line circulators are favored due to their planar structure, small size, and ease of integration. However, traditional microstrip line circulators require a strong external bias magnetic field to magnetize the ferrite material to saturation. This bias magnetic field is typically provided by bulky, high-cost permanent magnets such as neodymium iron boron, which severely limits the further miniaturization and integration of circulators. Summary of the Invention

[0003] M-type barium ferrite (BaFe) 12 O 19 As a high-performance permanent magnet, barium ferrite possesses a unique structure and characteristics such as high coercivity, saturation magnetization, uniaxial magnetocrystalline anisotropy, high remanence, and stable chemical properties, which can meet the required bias magnetic field, making it a highly promising circulator material. However, due to the large ferromagnetic resonance linewidth of barium ferrite, its magnetic loss is relatively high, and its limited anisotropic field also significantly restricts performance improvement. YIG ferrite (Y3Fe5O4) 12 It is one of the ferrite materials with the lowest known magnetic loss in the microwave band, which can ensure that the circulator has extremely low insertion loss and high isolation.

[0004] This research focuses on mainstream X-band applications and breaks with conventional circulator design through material innovation. The developed YIG-M type barium ferrite hybrid material retains the excellent properties of YIG while introducing the permanent magnet characteristics of barium ferrite to provide an internal bias field. Simulation results show that this design significantly reduces the field strength requirements of the external permanent magnet, providing a key basis for directly reducing magnet volume and filling the gap in small-volume, medium-performance circulator design for this frequency band. Therefore, we hybridize low-loss YIG with high-remanence M-type barium ferrite at the material level, achieving both low loss and minimizing the volume of the external permanent magnet using high remanence. Furthermore, materials with superior static magnetic properties also exhibit better stability and a wider operating bandwidth in circulators.

[0005] The purpose of this invention is to provide a hybrid material Y3Fe5O for microstrip circulators that has high remanence and low loss.12 -BaFe 12 O 19 (Y3Fe5O 12 -BaFe 12 O 19 A method for preparing YIG-M type barium ferrite (Y2B1, Y1B1, Y1B2, where the mass ratio of YIG to barium ferrite is 2:1, 1:1, 1:2) was described. A YIG-M type barium ferrite hybrid material was prepared by solid-state reaction, and the magnetic properties of the material were optimized by controlling the mass ratio of the two components.

[0006] A method for preparing a YIG-M type barium ferrite hybrid material for microstrip circulators includes the following steps:

[0007] Step 1: Dissolve Y2O3 and Fe2O3 powders in a solvent, add a certain amount of zirconium balls and ball mill to obtain solution 1; dissolve BaCO3 and Fe2O3 powders in a solvent, add a certain amount of zirconium balls and ball mill to obtain solution 2; dry solution 1 and solution 2 respectively, and then sieve them to obtain powder 1 and powder 2 respectively.

[0008] Step 2: Powder 1 and powder 2 are pre-sintered to obtain precursor powder 1 and precursor powder 2, respectively. Then, precursor powder 1 and precursor powder 2 are ball-milled twice to obtain solution 3 and solution 4, respectively.

[0009] Step 3: Dry solutions 3 and 4 to obtain YIG precursor powder and barium ferrite powder; press the YIG precursor powder into a green compact and sinter it to obtain YIG ferrite with phase formation.

[0010] Step 4: After crushing the YIG ferrite, mix it with barium ferrite precursor powder in a mass ratio of 1:2 to 2:1, press it into a green blank, and sinter it to obtain YIG-M type barium ferrite mixed material.

[0011] Preferably, in step 1, the mass parts of Y2O3, Fe2O3, zirconium spheres and anhydrous ethanol are 16.953 parts, 20.164 parts, 18.5 parts and 55.23 parts, respectively.

[0012] Preferably, in step 1, the ball milling is performed in a planetary ball mill with a rotation speed of 280 r / min set in unidirectional operation mode for 16 hours.

[0013] Preferably, in step 1, drying solution 1 and solution 2 separately includes: placing solution 1 and solution 2 in different ovens and drying them at a temperature of 100°C for 1 day.

[0014] Preferably, in step 2, the sintering temperature of powder 1 is 1200℃, the heating rate is set to 2℃ / min, and the temperature is held at 1200℃ for 4 hours.

[0015] Preferably, in step 2, the sintering temperature of the powder 2 pre-sintering is 1100℃, the heating rate is set to 2℃ / min, and the temperature is held at 1100℃ for 3h.

[0016] Preferably, in step 3, pressing the YIG precursor powder into a green embryo specifically includes:

[0017] PVA was added to the YIG precursor powder to ensure uniform mixing and fluidity of the mixture; the mass fraction of PVA in the mixture was 15%.

[0018] The pressure is applied using a hydraulic press, with a pressure of 10-15 MPa and a holding time of approximately 5 seconds.

[0019] Preferably, in step 3, the final sintering temperature of YIG is 1420℃, the heating rate is 2℃ / min, the temperature is first held at 450℃ for 3h for debinding, then the temperature is raised to 1420℃ at a rate of 2℃ / min and held for 6h, and finally the cooling rate is controlled at 1-1.2℃ / min to slowly reduce to room temperature.

[0020] Preferably, in step 4, the crushing specifically includes: grinding into granules using a grinding mortar.

[0021] Preferably, in step 4, the sintering phase formation specifically includes: the sintering temperature is 1250℃, the heating rate is 2℃ / min, first holding at 450℃ for 3h to perform debinding treatment, then continuing to raise to 1250℃ at a rate of 2℃ / min and holding for 3h, and finally controlling the cooling rate to slowly lower to room temperature at 1-1.2℃ / min.

[0022] Beneficial effects:

[0023] (1) The YIG-M type barium ferrite calcined in this invention combines the advantages of both, wherein the Y2B1 sample has a strength of 1.66 × 10⁻⁶ at a resonant frequency of 11.301 GHz. -3 The dielectric loss tangent of the Y1B2 sample is much lower than that of barium ferrite; the saturation magnetization of the Y1B2 sample is as high as 51.1 emu / g, the remanence is about 950 Gs, and the coercivity is 2290 Oe, which far exceeds the static magnetic properties of YIG ferrite.

[0024] (2) The hybrid material Y1B1 prepared in this invention has a relative permittivity of 13.632, a ferromagnetic resonance linewidth of 202.73 Oe at 9.65 GHz, and a dielectric loss of 18.218 × 10⁻⁶.-4 The saturation magnetization of 4πMs, 2396 Gs, was solved in HFSS 2023R1 simulation software at a working frequency of 10 GHz. It was found to exhibit good circumduction in the X-band, and its high remanence also provides a partial bias magnetic field for the ferrite substrate. Its isolation performance is even better in the -20 dB bandwidth: traditional YIG materials require only about 1 GHz, while the hybrid material jumps to over 2 GHz. Traditional YIG materials require an external bias magnetic field of 180 kA / m to achieve this performance, while our prepared Y1B1 hybrid material only requires 92 kA / m, a reduction of half. This means that we only need a smaller permanent magnet to achieve a good circumduction effect.

[0025] (3) This invention does not require the use of highly toxic chemical reagents, and the preparation method does not require complex synthesis equipment. The process is simple and low-cost, and can be used for large-scale industrial production. Attached Figure Description

[0026] The features described in one aspect or implementation may also be applicable to other aspects and implementations. Specific implementations will now be described in conjunction with the accompanying drawings and embodiments, which are provided merely as examples to further illustrate the invention.

[0027] In the attached diagram:

[0028] Figure 1 The X-ray diffraction pattern of the YIG-M type barium ferrite in the embodiment is shown below.

[0029] Figure 2 SEM images of three groups of YIG-M type barium ferrite hybrid materials with different mass ratios obtained in the examples;

[0030] Figure 3 The effect of the mass ratio of M-type barium ferrite on the magnetic properties of the prepared hybrid material;

[0031] Figure 4 The three groups of Y obtained in the example x B x Ferromagnetic resonance (FMR) spectrum of the sample;

[0032] Figure 5 This is a schematic diagram of the S-parameters in the HFSS 2023R1 simulation software when the Y1B1 sample and the conventional YIG material are used as ferrite substrates in the examples. Detailed Implementation

[0033] To make the above-mentioned objectives, technical solutions, and advantages of the present invention clearer and more easily understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Those skilled in the art can make various modifications or additions to the following specific embodiments or use similar methods to replace them, as long as they do not depart from the concept or example of the present invention, or do not exceed the scope defined by the claims, all of which should fall within the protection scope of the present invention.

[0034] General Example

[0035] A method for preparing a YIG-M type barium ferrite hybrid material for microstrip circulators includes the following steps:

[0036] (1) Step 1: Dissolve Y2O3 and Fe2O3 powders in anhydrous ethanol, add a certain amount of zirconium balls and ball mill to obtain solution 1; dissolve BaCO3 and Fe2O3 powders in anhydrous ethanol, add a certain amount of zirconium balls and ball mill to obtain solution 2; place solution 1 and solution 2 in an oven to dry, and then sieve them through a 40-mesh sieve to obtain fine powder 1 and powder 2.

[0037] (2) Step 2: The fine powder 1 and powder 2 from step 1 are pre-sintered in a muffle furnace at 1200℃ and 1100℃ respectively, so that they can react fully to obtain precursor powder 1 and precursor powder 2; the precursor powder 1 and powder 2 are placed in a ball mill jar again, anhydrous ethanol and zirconium balls are added, and the mixture is ball-milled a second time to obtain solution 3 and solution 4 respectively.

[0038] (3) Step 3: Place the solution 3 and solution 4 after the second ball milling in step 2 in an oven to dry to obtain YIG precursor powder and barium ferrite powder. Then, further refine the powder by passing it through a 60-mesh sieve. Mix the YIG precursor powder with a certain amount of PVA, grind it in a grinding bowl, and then press it into a round cake shape under a hydraulic press using a special mold. Finally, sinter it in a muffle furnace at 1420℃ to obtain YIG ferrite.

[0039] (4) Step 4: Crush the YIG ferrite disc that has already formed phase in step 3 and set it aside. Mix the barium ferrite precursor powder in step 3 with it in a certain mass ratio, add PVA and grind it, press it into a green material of the mixture, and finally sinter it in a muffle furnace at 1250℃ to obtain the YIG-M type barium ferrite mixture.

[0040] In step 1, the amounts of anhydrous ethanol added to solution 1 and solution 2 are 70 ml and 20 ml, respectively.

[0041] In step 1, the amounts of Y2O3, BaCO3, and Fe2O3 added are 16.953g, 7.973g, and 20.164g (used for preparing YIG) and 38.715g (used for preparing barium ferrite), respectively.

[0042] In step 1, the mass of zirconium spheres added to the YIG is 18.5g, and the mass of zirconium spheres added to the barium ferrite is 140g.

[0043] In step 1, the ball milling speeds are 250 r / min and 280 r / min, respectively.

[0044] In step 1, the oven temperature is 100℃ and the time is 1 day.

[0045] In step 2, the heating rate of the heat treatment is 3 ℃ / min.

[0046] In step 2, the heat preservation time for pre-sintering is 3-4 hours.

[0047] In step 3, the mass fraction of PVA added is 15%.

[0048] In step 4, the pressure applied by the hydraulic press is between 10 and 15 MPa.

[0049] Example:

[0050] A method for preparing a YIG-M type barium ferrite hybrid material for microstrip circulators includes the following steps:

[0051] (1) Step 1: Weigh 16.953g of Y2O3 and 20.164g of Fe2O3 powder and dissolve them together in 70 ml of anhydrous ethanol. Then add 18.5g of zirconium balls and continuously ball mill the solution in a planetary ball mill at a running speed of 280 r / min for 16 h to form solution 1. Weigh 7.973g of BaCO3 and 38.715g of Fe2O3 powder and dissolve them together in 20 ml of anhydrous ethanol. Then add 140g of zirconium balls and continuously ball mill the solution in a planetary ball mill at a running speed of 250 r / min for 12 h to form solution 2. Place solutions 1 and 2 in an oven and dry them at 100℃ for 1 day. Then pass them through a 40-mesh sieve to obtain powders 1 and 2.

[0052] (2) Step 2: Place the powder 1 obtained in Step 1 into an alumina crucible, heat it to 1200℃ in a muffle furnace at a rate of 2℃ / min and hold it for 4 hours to obtain fluffy powder 1; place the powder 2 obtained in Step 1 into an alumina crucible, heat it to 1100℃ in a muffle furnace at a rate of 2℃ / min and hold it for 3 hours to obtain fluffy powder 2. Ball mill the fluffy powder 1 and fluffy powder 2 again according to the ball-to-powder ratio in Step 1.

[0053] (3) Step 3: Place the solution after the second ball milling in Step 2 in an oven and dry it at 100℃ for 1 day. Then pass it through a 60-mesh sieve to obtain fine precursor powder and barium ferrite precursor powder. Mix the YIG precursor powder with 15% PVA by mass and grind it in a grinding bowl until it is fluid. Then, in a special mold, apply a pressure of 10-15 MPa through a hydraulic press and hold the pressure for about 5 seconds to remove the YIG sample green. Place the disc-shaped YIG green in a corundum crucible and heat it to 450℃ in a muffle furnace at a heating rate of 2℃ / min. Hold it at this temperature for 3 hours to remove the binder. Then, continue to heat it to 1420℃ at a rate of 2℃ / min and hold it for 6 hours. Finally, control the cooling rate to slowly cool it to room temperature at a rate of 1-1.2℃ / min to obtain pure YIG ferrite.

[0054] (4) Step 4: Crush the pure YIG ferrite sample prepared in Step 3 in a grinding mortar until it becomes powder and sieve it for later use. Mix the barium ferrite precursor powder from Step 3 with the pure YIG powder, wherein the mass ratio of YIG powder to barium ferrite precursor powder is 2:1, 1:1, and 1:2, respectively. Then add 15% PVA by mass and mix. Grind in a grinding mortar until it becomes fluid. Take a special mold and press it under a hydraulic press at a pressure of 10-15 MPa for about 5 seconds to form a round green cake, which is then placed in a corundum crucible. In a muffle furnace, heat the temperature to 450℃ at a heating rate of 2℃ / min and hold for 3 hours for debinding. Then continue to heat the temperature to 1250℃ at a rate of 2℃ / min and hold for 3 hours. Finally, control the cooling rate to slowly reduce the temperature to room temperature at a rate of 1-1.2℃ / min to obtain YIG-M type barium ferrite mixed materials with different mass ratios. The produced samples were labeled as Y2B1, Y1B1, and Y1B2, respectively.

[0055] Table 1 Comparison of performance parameters of each sample

[0056]

[0057] Table 1 shows the dielectric loss and relative permittivity of different YIG-M type barium ferrite samples at their respective resonant frequencies. It can be observed that as the mass ratio of YIG gradually increases, the relative permittivity of the samples decreases, and the dielectric loss also gradually decreases. In particular, the dielectric loss of Y1B1 decreases by 40.272 × 10⁻⁶ compared to Y1B2. -4 .

[0058] Figure 1 The X-ray diffraction pattern of the YIG-M type barium ferrite in the examples shows that all samples have similar diffraction peaks, and BaFe can be observed in all of them. 12 O 19Phase with Y3Fe5O 12 The presence of a complete phase indicates that the mixed material is structurally sound and the proposed solution is feasible.

[0059] Figure 2 The images show three sets of SEM images of YIG-M type barium ferrite mixed materials with different mass ratios obtained in the example. As can be seen from the images, with the increase of M type barium ferrite content, the number of hexagonal grains on the sample surface increases significantly, and the number of large pores on the sample surface decreases.

[0060] Figure 3 The graph shows the effect of the mass percentage of M-type barium ferrite on the magnetic properties of the prepared hybrid material. The horizontal axis represents the mass percentage of M-type barium ferrite, the left vertical axis represents the saturation magnetization (Ms) in emu / g, and the right vertical axis represents the coercivity (Hc) in kOe. As can be seen from the graph, both the saturation magnetization and coercivity increase significantly with the increase of the mass percentage of M-type barium ferrite.

[0061] Figure 4 The three groups of Y obtained in the example x B x The ferromagnetic resonance (FMR) spectra of the samples were obtained by fitting nonlinear curves to determine the ferromagnetic resonance linewidths. It was observed that with the increase of M-type barium ferrite, the linewidth did not increase significantly and remained slightly greater than 200 Oe, which is consistent with the porosity observed in SEM.

[0062] Figure 5 The diagram shows the S-parameters of the Y1B1 sample and the conventional YIG material as ferrite substrates in the HFSS 2023R1 simulation software. It can be observed that although the insertion loss of the circulator increases only slightly (about 0.2 dB, still below 1 dB) with the hybrid material, its isolation is significantly improved, and its isolation performance in the -20 dB bandwidth is superior: the conventional YIG material requires only about 1 GHz, while the hybrid material jumps to over 2 GHz. Most importantly, the conventional YIG material requires an external bias magnetic field of 180 kA / m to achieve this performance, while the Y1B1 hybrid material we prepared only requires 92 kA / m, a reduction of half. This means that we can achieve excellent circulator performance with a smaller permanent magnet.

[0063] Those skilled in the art related to this embodiment will understand that various changes in form and detail can be made therein without departing from the scope of the above features. Therefore, the disclosed method should be considered descriptive rather than restrictive. The scope of this disclosure is defined by the appended claims rather than the foregoing description, and all differences within the scope of their equivalents should be interpreted as included in this disclosure.

Claims

1. A method for preparing a YIG-M type barium ferrite hybrid material for microstrip circulators, characterized in that, Includes the following steps: Step 1: Dissolve Y2O3 and Fe2O3 powders in a solvent, add a certain amount of zirconium balls and ball mill to obtain solution 1; dissolve BaCO3 and Fe2O3 powders in a solvent, add a certain amount of zirconium balls and ball mill to obtain solution 2; dry solution 1 and solution 2 respectively, and then sieve them to obtain powder 1 and powder 2 respectively. Step 2: Powder 1 and powder 2 are pre-sintered to obtain precursor powder 1 and precursor powder 2, respectively. Then, precursor powder 1 and precursor powder 2 are ball-milled twice to obtain solution 3 and solution 4, respectively. Step 3: Dry solutions 3 and 4 to obtain YIG precursor powder and barium ferrite powder; press the YIG precursor powder into a green compact and sinter it to obtain YIG ferrite with phase formation. Step 4: After crushing the YIG ferrite, mix it with barium ferrite precursor powder in a mass ratio of 1:2 to 2:1, press it into a green blank, and sinter it to obtain YIG-M type barium ferrite mixed material.

2. The preparation method according to claim 1, characterized in that: In step 1, the mass fractions of Y2O3, Fe2O3, zirconium spheres, and anhydrous ethanol are 16.953 parts, 20.164 parts, 18.5 parts, and 55.23 parts, respectively.

3. The preparation method according to claim 1, characterized in that: In step 1, the ball mill is set to a rotation speed of 280 r / min in the unidirectional operation mode of the planetary ball mill and run for 16 hours.

4. The preparation method according to claim 1, characterized in that: In step 1, drying solution 1 and solution 2 separately includes placing solution 1 and solution 2 in different ovens and drying them at 100°C for 1 day.

5. The preparation method according to claim 1, characterized in that: In step 2, the pre-sintering temperature of powder 1 is 1200℃, the heating rate is set to 2℃ / min, and the temperature is held at 1200℃ for 4h.

6. The preparation method according to claim 1, characterized in that: In step 2, the pre-sintering temperature of powder 2 is 1100℃, the heating rate is set to 2℃ / min, and the temperature is held at 1100℃ for 3h.

7. The preparation method according to claim 1, characterized in that: Step 3, which involves pressing the YIG precursor powder into a green embryo, specifically includes: PVA was added to the YIG precursor powder to ensure uniform mixing and fluidity of the mixture; the mass fraction of PVA in the mixture was 15%. The pressure is applied using a hydraulic press, with a pressure of 10-15 MPa and a holding time of approximately 5 seconds.

8. The preparation method according to claim 1, characterized in that: In step 3, the final sintering temperature of YIG is 1420℃, the heating rate is 2℃ / min, and it is first held at 450℃ for 3h to remove the binder. Then, it is raised to 1420℃ at a rate of 2℃ / min and held for 6h. Finally, the cooling rate is controlled at 1-1.2℃ / min to slowly reduce to room temperature.

9. The preparation method according to claim 1, characterized in that: In step 4, the crushing specifically includes: grinding into granules using a grinding mortar.

10. The preparation method according to claim 1, characterized in that: In step 4, the sintering phase formation specifically includes: the sintering temperature is 1250℃, the heating rate is 2℃ / min, the temperature is first held at 450℃ for 3h to perform the debinding process, then the temperature is raised to 1250℃ at a rate of 2℃ / min and held for 3h, and finally the cooling rate is controlled at 1-1.2℃ / min to slowly cool down to room temperature.

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