Preparation method of high dielectric constant small line width yttrium iron garnet ferrite material

Abstract

A method for preparing high dielectric constant, small linewidth yttrium iron garnet ferrite material belongs to the field of ferrite material preparation technology. This invention utilizes the dodecahedral Y-axis in the garnet structure... 3+ octahedral Fe 3+ Instead of using a traditional method, this invention employs a two-stage pre-calcination process and a three-stage ball milling process (low speed followed by high speed), requiring only three ball milling operations, one granulation operation, and one sintering operation to produce yttrium iron garnet ferrite materials. The two-stage pre-calcination process results in better powder activity, a higher degree of solid-state reaction completion during sintering, and superior material properties. The three-stage ball milling process, using a low-speed followed by a high-speed process, enhances the particle size uniformity of the milled powder. The resulting ferrite exhibits a high dielectric constant ε' > 20, a low ferromagnetic resonance linewidth ΔH ≤ 25Oe, and a low dielectric loss tanδ. ε <1×10 ‑4 .

Description

Technical Field

[0001] This invention belongs to the field of ferrite material preparation technology, specifically relating to a method for preparing yttrium iron garnet ferrite material with high dielectric constant and small linewidth. Background Technology

[0002] Microwave ferrite devices play a crucial role in microwave technology, finding wide application in aerospace, satellite communications, electronic warfare, mobile communications, and medical fields. Microwave ferrite materials are used in devices such as circulators, isolators, and phase shifters, performing functions such as isolation, path selection, phase shifting, polarization control, switching, modulation, frequency doubling, and amplification in microwave systems. Yttrium iron garnet ferrite (YIG) has advantages such as small linewidth and low dielectric loss; however, conventional YIG ferrite has a low dielectric constant (approximately 13-16). According to ferrite device design theory, the higher the dielectric constant of a ferrite material, the smaller the size of the ferrite device. This makes it difficult to achieve miniaturization and integration of devices. Therefore, high-dielectric-constant yttrium iron garnet ferrite materials have gradually become an important research topic in the field of microwave ferrite research.

[0003] On March 7, 2022, CN114436637B disclosed a high-dielectric-constant, high-power microwave ferrite material, belonging to the field of microwave and magnetic materials technology, with the chemical formula: Y. 3-x-y-a-b-c-d-e-f Bi x La y Lu z Gd a Nd b Sm c Dy d Ca e+ f Sn e Zr f Fe 5-δ-e-f O 12 Where 0.8≤x≤1.6, 0≤y+z≤0.2, 0≤a≤0.7, 0≤b+c≤0.06, 0.005≤d≤0.05, 0.25≤e+f≤0.55, δ is the iron deficiency, 0.03≤δ≤0.1, the dielectric constant of the material ε'>20, and the dielectric loss tanδ ε <2×10 -4 Spin wave linewidth ΔH k >5Oe, ferromagnetic resonance linewidth ΔH≤40Oe, 4πM s ≥1700G, Curie temperature T c >270℃. Although the material has a high Curie temperature, it also has high dielectric loss, high ferromagnetic resonance linewidth, and introduces a large number of rare earth ions, which significantly increases the cost.

[0004] On April 13, 2023, CN116514535A disclosed a high-dielectric, low-linewidth garnet ferrite material and its preparation method, as well as a microstrip circulator, relating to microwave magnetic materials and device technology. The chemical formula is: Bi. a Ca b Y c Zr d In e Fe 5-d-e-δ O 12 The dielectric constant of the material is 28-30, where 0 ≤ a ≤ 1.4, 0 ≤ b ≤ 0.6, 0 ≤ c ≤ 3, 0 ≤ d ≤ 0.6, 0 ≤ e ≤ 1.4, and 0 ≤ δ ≤ 0.06. s =1855G, ΔH=28Oe, tanδ ε <2×10 -4 Curie temperature T c =232℃. Although the chemical formula does not introduce rare earth ions and has good magnetic properties, the preparation process requires three ball millings, two granulations, and two sinterings, which is quite complex. In contrast, the preparation process of this invention only requires three ball millings, one granulation, and one sintering, making it simpler. Furthermore, Bi... 3+ It requires less substitution and has good process stability. Summary of the Invention

[0005] The purpose of this invention is to address the problems existing in the background technology by proposing a method for preparing yttrium iron garnet ferrite materials with high dielectric constant and small linewidth. This invention utilizes the dodecahedral Y-axis in the garnet structure... 3+ octahedral Fe 3+ The replacement process employs a two-stage pre-sintering process and a three-stage ball milling process, first at low speed and then at high speed, resulting in ferrites with higher dielectric constant (dielectric constant ε'>20), lower ferromagnetic resonance linewidth (ferromagnetic resonance linewidth ΔH≤25Oe), and lower dielectric loss (tanδ). ε <1×10 -4 ).

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for preparing a high dielectric constant, small linewidth yttrium iron garnet ferrite material includes the following steps:

[0008] Step 1, Ingredients:

[0009] Using Y₂O₃, Bi₂O₃, CaCO₃, ZrO₂, and Fe₂O₃ as raw materials, according to the chemical formula Y 3-x-y Bi x Cay Zr y Fe 5-y O 12 Calculate the stoichiometric ratio and weigh the raw materials; where 0.7≤x≤1.0, 0.3≤y≤0.45;

[0010] Step 2, First ball milling:

[0011] Add the powder weighed in step 1 to deionized water and dispersant and ball mill once. The ball mill speed is 200 rpm and the ball milling time is 4-6 hours.

[0012] Step 3, Preheating:

[0013] After drying the primary ball milling material obtained in step 2, a pre-firing is performed at a temperature of 500-600℃ for 1-2 hours.

[0014] Step 4, Secondary ball milling:

[0015] Add deionized water to the pre-calcined material obtained in step 3 for secondary ball milling. The ball mill speed is 200 rpm and the ball milling time is 4-6 hours.

[0016] Step 5, Secondary Pre-firing:

[0017] After drying the secondary ball milling material obtained in step 4, it is subjected to secondary pre-firing at a temperature of 800-900℃ for 4-6 hours.

[0018] Step 6, three rounds of ball milling:

[0019] Add deionized water to the secondary pre-calcined material obtained in step 5 and ball mill it three times. First, ball mill at 160 rpm for 1-2 hours, and then ball mill at 200 rpm for 10-20 hours.

[0020] Step 7, Granulation:

[0021] After drying the three-stage ball milling material obtained in step 6, an adhesive is added for granulation.

[0022] Step 8: Shaping

[0023] The granulated material obtained in step 7 is pressed into shape with a pressing pressure of 110 MPa.

[0024] Step 9, Sintering:

[0025] The green blank formed in step 8 is sintered at a temperature of 1000-1120℃ for more than 10 hours. After sintering, it is naturally cooled to room temperature to obtain the yttrium iron garnet ferrite material.

[0026] Furthermore, the purity of each raw material in step 1 is as follows: Y2O3 purity 99.99%, Fe2O3 purity 99.6%, CaCO3 purity 99.11%, Bi2O3 purity 99%, and ZrO2 purity 99%.

[0027] Furthermore, in step 2, the mass ratio of balls:material:deionized water:dispersant is 3.5:1:0.9:0.002.

[0028] Furthermore, in step 4, the mass ratio of balls:material:deionized water is 3.5:1:0.9, and no dispersant is added.

[0029] Furthermore, in step 6, the mass ratio of balls:material:deionized water is 3.5:1:0.8, and no dispersant is added.

[0030] Furthermore, in step 7, the adhesive is an aqueous solution of polyvinyl alcohol (PVA) with a concentration of 5wt%-15wt%.

[0031] Furthermore, the sintering process in step 9 is a multi-stage sintering process. The specific process is as follows: starting from room temperature, the temperature is raised to 80°C in 30 minutes, then raised to 250°C in 2.5 hours, then raised to 400°C in 2.5 hours, then raised to 200°C below the target sintering temperature at a rate of 2.5°C / min, held for 3 hours, and finally raised to the target sintering temperature (1000-1120°C) in 4 hours, held for more than 10 hours, and then cooled naturally after the holding period.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] 1. The present invention provides a method for preparing high dielectric constant and small linewidth yttrium iron garnet ferrite material. The preparation process adopts a two-stage pre-calcination process, which improves the activity of the powder, increases the degree of solid-phase reaction completion during the sintering stage, and results in superior material performance. The three-stage ball milling adopts a process of first low speed and then high speed to enhance the particle size uniformity of the powder. The formula without rare earth ion substitution is used, resulting in lower material cost.

[0034] 2. The high dielectric constant and small linewidth yttrium iron garnet ferrite material prepared by this invention has a dielectric constant ε' > 20 and a dielectric loss tanδ ε <1×10 -4 Ferromagnetic resonance linewidth ΔH≤25Oe, saturation magnetization 4πM s >1900G, Curie temperature T c Temperatures above 240℃ can effectively reduce the design size of microwave ferrite devices, meet miniaturization requirements, and reduce device insertion loss. Attached Figure Description

[0035] Figure 1The image shows the XRD results of the phase analysis of the ferrite material in Example 1.

[0036] Figure 2 The image shows the SEM results of the phase analysis of the ferrite material in Example 1.

[0037] Figure 3 The image shows the XRD results of the phase analysis of the ferrite material in Example 2.

[0038] Figure 4 The image shows the SEM results of the phase analysis of the ferrite material in Example 2.

[0039] Figure 5 The image shows the XRD results of the phase analysis of the ferrite material in Example 3.

[0040] Figure 6 The image shows the SEM results of the phase analysis of the ferrite material in Example 3. Detailed Implementation

[0041] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0042] Example 1

[0043] A method for preparing a high dielectric constant, small linewidth yttrium iron garnet ferrite material includes the following steps:

[0044] Step 1, Ingredients:

[0045] Using Y₂O₃ with a purity of 99.99%, Bi₂O₃ with a purity of 99%, CaCO₃ with a purity of 99.11%, ZrO₂ with a purity of 99%, and Fe₂O₃ with a purity of 99.6% as raw materials, according to the chemical formula Y 3-x-y Bi x Ca y Zr y Fe 5-y O 12 The stoichiometric ratio was calculated and the raw materials were weighed; where x = 0.7 and y = 0.3;

[0046] Step 2, First ball milling:

[0047] Add the powder weighed in step 1 to deionized water and dispersant and ball mill once. The ball mill speed is 200 rpm and the ball milling time is 5 hours.

[0048] Step 3, Preheating:

[0049] After drying the primary ball milling material obtained in step 2, it is pre-fired at a temperature of 550℃ for 1 hour.

[0050] Step 4, Secondary ball milling:

[0051] The pre-calcined material obtained in step 3 was added to deionized water for secondary ball milling at a speed of 200 rpm for 5 hours.

[0052] Step 5, Secondary Pre-firing:

[0053] After drying the secondary ball milling material obtained in step 4, it is subjected to secondary pre-firing at a temperature of 800℃ for 4 hours.

[0054] Step 6, three rounds of ball milling:

[0055] The secondary pre-calcined material obtained in step 5 was added to deionized water and ball-milled three times, first at 160 rpm for 1 hour, and then at 200 rpm for 15 hours.

[0056] Step 7, Granulation:

[0057] After drying the three-stage ball milling material obtained in step 6, a 7.5 wt% polyvinyl alcohol (PVA) aqueous solution was added for granulation.

[0058] Step 8: Shaping

[0059] The granulated material obtained in step 7 is pressed into shape with a pressing pressure of 110 MPa.

[0060] Step 9, Sintering:

[0061] Starting from room temperature, the temperature is increased to 80℃ over 30 minutes, then to 250℃ over 2.5 hours, then to 400℃ over another 2.5 hours, then increased to 920℃ at a rate of 2.5℃ / min, held for 3 hours, and finally increased to 1120℃ over 4 hours, held for more than 10 hours, and then allowed to cool naturally after the holding period.

[0062] Example 2

[0063] A method for preparing a high dielectric constant, small linewidth yttrium iron garnet ferrite material includes the following steps:

[0064] Step 1, Ingredients:

[0065] Using Y₂O₃ with a purity of 99.99%, Bi₂O₃ with a purity of 99%, CaCO₃ with a purity of 99.11%, ZrO₂ with a purity of 99%, and Fe₂O₃ with a purity of 99.6% as raw materials, according to the chemical formula Y 3-x-y Bi x Ca y Zr y Fe 5-y O 12 The stoichiometric ratio was calculated and the raw materials were weighed; where x = 1.0 and y = 0.3;

[0066] Step 2, First ball milling:

[0067] Add the powder weighed in step 1 to deionized water and dispersant and ball mill once. The ball mill speed is 200 rpm and the ball milling time is 5 hours.

[0068] Step 3, Preheating:

[0069] After drying the primary ball milling material obtained in step 2, it is pre-fired at a temperature of 600℃ for 2 hours.

[0070] Step 4, Secondary ball milling:

[0071] The pre-calcined material obtained in step 3 was added to deionized water for secondary ball milling at a speed of 200 rpm for 5 hours.

[0072] Step 5, Secondary Pre-firing:

[0073] After drying the secondary ball milling material obtained in step 4, it is subjected to secondary pre-firing at a temperature of 800℃ for 4 hours.

[0074] Step 6, three rounds of ball milling:

[0075] The secondary pre-calcined material obtained in step 5 was added to deionized water and ball-milled three times, first at 160 rpm for 2 hours, and then at 200 rpm for 20 hours.

[0076] Step 7, Granulation:

[0077] After drying the three-stage ball milling material obtained in step 6, a 7.5 wt% polyvinyl alcohol (PVA) aqueous solution was added for granulation.

[0078] Step 8: Shaping

[0079] The granulated material obtained in step 7 is pressed into shape with a pressing pressure of 110 MPa.

[0080] Step 9, Sintering:

[0081] Starting from room temperature, the temperature is increased to 80℃ over 30 minutes, then to 250℃ over 2.5 hours, then to 400℃ over another 2.5 hours, then increased to 820℃ at a rate of 2.5℃ / min, held for 3 hours, and finally increased to 1020℃ over 4 hours, held for more than 10 hours, and then allowed to cool naturally after the holding period.

[0082] Example 3

[0083] A method for preparing a high dielectric constant, small linewidth yttrium iron garnet ferrite material includes the following steps:

[0084] Step 1, Ingredients:

[0085] Using Y₂O₃ with a purity of 99.99%, Bi₂O₃ with a purity of 99%, CaCO₃ with a purity of 99.11%, ZrO₂ with a purity of 99%, and Fe₂O₃ with a purity of 99.6% as raw materials, according to the chemical formula Y 3-x-y Bi x Ca y Zr y Fe 5-y O 12 The stoichiometric ratio was calculated and the raw materials were weighed; where x = 1.0 and y = 0.45;

[0086] Step 2, First ball milling:

[0087] Add the powder weighed in step 1 to deionized water and dispersant and ball mill once. The ball mill speed is 200 rpm and the ball milling time is 5 hours.

[0088] Step 3, Preheating:

[0089] After drying the primary ball milling material obtained in step 2, it is pre-fired at a temperature of 600℃ for 2 hours.

[0090] Step 4, Secondary ball milling:

[0091] The pre-calcined material obtained in step 3 was added to deionized water for secondary ball milling at a speed of 200 rpm for 5 hours.

[0092] Step 5, Secondary Pre-firing:

[0093] After drying the secondary ball milling material obtained in step 4, it is subjected to secondary pre-firing at a temperature of 800℃ for 4 hours.

[0094] Step 6, three rounds of ball milling:

[0095] The secondary pre-calcined material obtained in step 5 was added to deionized water and ball-milled three times, first at 160 rpm for 2 hours, and then at 200 rpm for 20 hours.

[0096] Step 7, Granulation:

[0097] After drying the three-stage ball milling material obtained in step 6, a 7.5 wt% polyvinyl alcohol (PVA) aqueous solution was added for granulation.

[0098] Step 8: Shaping

[0099] The granulated material obtained in step 7 is pressed into shape with a pressing pressure of 110 MPa.

[0100] Step 9, Sintering:

[0101] Starting from room temperature, the temperature is increased to 80℃ over 30 minutes, then to 250℃ over 2.5 hours, then to 400℃ over another 2.5 hours, then increased to 840℃ at a rate of 2.5℃ / min, held for 3 hours, and finally increased to 1040℃ over 4 hours, held for more than 10 hours, and then allowed to cool naturally after the holding period.

[0102] Comparative Example 1

[0103] Step 1, Ingredients:

[0104] Using Y₂O₃ with a purity of 99.99%, Bi₂O₃ with a purity of 99%, CaCO₃ with a purity of 99.11%, ZrO₂ with a purity of 99%, and Fe₂O₃ with a purity of 99.6% as raw materials, according to the chemical formula Y 3-x-y Bi x Ca y Zr y Fe 5-y O 12 The stoichiometric ratio was calculated and the raw materials were weighed; where x = 0.7 and y = 0.3;

[0105] Step 2, First ball milling:

[0106] Add the powder weighed in step 1 to deionized water and dispersant and ball mill once. The ball mill speed is 200 rpm and the ball milling time is 5 hours.

[0107] Step 3, Preheating:

[0108] After drying the primary ball milling material obtained in step 2, it is pre-fired at a temperature of 800℃ for 4 hours.

[0109] Step 4, Secondary ball milling:

[0110] The pre-calcined material obtained in step 3 was added to deionized water and ball-milled a second time at 200 rpm for 16 hours.

[0111] Step 5, Granulation:

[0112] After drying the secondary ball milling material obtained in step 4, a 7.5 wt% polyvinyl alcohol (PVA) aqueous solution was added for granulation.

[0113] Step 6, Shaping:

[0114] The granulated material obtained in step 5 is pressed into shape with a pressing pressure of 110 MPa.

[0115] Step 7, Sintering:

[0116] The green blank formed in step 6 is sintered at a temperature of 1120℃ for more than 10 hours. After sintering, it is naturally cooled to room temperature.

[0117] Comparative Example 2

[0118] Step 1, Ingredients:

[0119] Using Y₂O₃ with a purity of 99.99%, Bi₂O₃ with a purity of 99%, CaCO₃ with a purity of 99.11%, ZrO₂ with a purity of 99%, and Fe₂O₃ with a purity of 99.6% as raw materials, according to the chemical formula Y 3-x-y Bi x Ca y Zr y Fe 5-y O 12 The stoichiometric ratio was calculated and the raw materials were weighed; where x = 1.0 and y = 0.3;

[0120] Step 2, First ball milling:

[0121] Add the powder weighed in step 1 to deionized water and dispersant and ball mill once. The ball mill speed is 200 rpm and the ball milling time is 5 hours.

[0122] Step 3, Preheating:

[0123] After drying the primary ball milling material obtained in step 2, it is pre-fired at a temperature of 600℃ for 2 hours.

[0124] Step 4, Secondary ball milling:

[0125] The pre-calcined material obtained in step 3 was added to deionized water for secondary ball milling at a speed of 200 rpm for 5 hours.

[0126] Step 5, Secondary Pre-firing:

[0127] After drying the secondary ball milling material obtained in step 4, it is subjected to secondary pre-firing at a temperature of 800℃ for 4 hours.

[0128] Step 6, three rounds of ball milling:

[0129] The secondary pre-calcined material obtained in step 5 was added to deionized water and ball-milled three times at 200 rpm for 22 hours.

[0130] Step 7, Granulation:

[0131] After drying the three-stage ball milling material obtained in step 6, a 7.5 wt% polyvinyl alcohol (PVA) aqueous solution was added for granulation.

[0132] Step 8: Shaping

[0133] The granulated material obtained in step 7 is pressed into shape with a pressing pressure of 110 MPa.

[0134] Step 9, Sintering:

[0135] The green blank formed in step 8 is sintered at a temperature of 1020℃ for more than 10 hours. After sintering, it is naturally cooled to room temperature.

[0136] Comparative Example 3

[0137] Step 1, Ingredients:

[0138] Using Y₂O₃ with a purity of 99.99%, Bi₂O₃ with a purity of 99%, CaCO₃ with a purity of 99.11%, ZrO₂ with a purity of 99%, and Fe₂O₃ with a purity of 99.6% as raw materials, according to the chemical formula Y 3-x-y Bi x Ca y Zr y Fe 5-y O 12 The stoichiometric ratio was calculated and the raw materials were weighed; where x = 1.0 and y = 0.45;

[0139] Step 2, First ball milling:

[0140] Add the powder weighed in step 1 to deionized water and dispersant and ball mill once. The ball mill speed is 200 rpm and the ball milling time is 5 hours.

[0141] Step 3, Preheating:

[0142] After drying the primary ball milling material obtained in step 2, it is pre-fired at a temperature of 600℃ for 2 hours.

[0143] Step 4, Secondary ball milling:

[0144] The pre-calcined material obtained in step 3 was added to deionized water for secondary ball milling at a speed of 200 rpm for 5 hours.

[0145] Step 5, Secondary Pre-firing:

[0146] After drying the secondary ball milling material obtained in step 4, it is subjected to secondary pre-firing at a temperature of 800℃ for 4 hours.

[0147] Step 6, three rounds of ball milling:

[0148] The secondary pre-calcined material obtained in step 5 was added to deionized water and ball-milled three times at 200 rpm for 22 hours.

[0149] Step 7, Granulation:

[0150] After drying the three-stage ball milling material obtained in step 6, a 7.5 wt% polyvinyl alcohol (PVA) aqueous solution was added for granulation.

[0151] Step 8: Shaping

[0152] The granulated material obtained in step 7 is pressed into shape with a pressing pressure of 110 MPa.

[0153] Step 9, Sintering:

[0154] The green blank formed in step 8 is sintered at a temperature of 1040℃ for more than 10 hours. After sintering, it is naturally cooled to room temperature.

[0155] The particle sizes of the tertiary ball milling materials obtained in Examples 1-3 and Comparative Examples 1-3 are shown in Table 1:

[0156] Table 1. Three-stage ball milling particle size of the examples and comparative samples.

[0157] granularity Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 D50(μm) 1.649 1.510 1.782 1.717 1.458 1.662 D90(μm) 2.768 2.527 3.329 3.845 3.134 4.048

[0158] The properties of the ferrite materials obtained in Examples 1-3 and Comparative Examples 1-3 are shown in Table 2:

[0159] Table 2. Basic performance of the examples and comparative samples

[0160]

Claims

1. A method for preparing a high dielectric constant, small linewidth yttrium iron garnet ferrite material, characterized in that, Includes the following steps: Step 1, Ingredients: Using Y₂O₃, Bi₂O₃, CaCO₃, ZrO₂, and Fe₂O₃ as raw materials, according to the chemical formula Y 3-x-y Bi x Ca y Zr y Fe 5-y O 12 Calculate the stoichiometric ratio and weigh the raw materials; where 0.7≤x≤1.0, 0.3≤y≤0.45; Step 2, First ball milling: The powder weighed in step 1 is ball-milled once at a speed of 200 rpm for 4-6 hours. Step 3, Preheating: After drying the primary ball milling material obtained in step 2, a pre-firing is performed at a temperature of 500-600℃ for 1-2 hours. Step 4, Secondary ball milling: The pre-calcined material obtained in step 3 is subjected to a second ball milling at a speed of 200 rpm for 4-6 hours. Step 5, Secondary Pre-firing: After drying the secondary ball milling material obtained in step 4, it is subjected to secondary pre-firing at a temperature of 800-900℃ for 4-6 hours. Step 6, three rounds of ball milling: The secondary pre-calcined material obtained in step 5 is ball-milled three times, first at 160 rpm for 1-2 hours, and then at 200 rpm for 10-20 hours. Step 7, Granulation: After drying, the three-stage ball milling material obtained in step 6 is granulated. Step 8: Shaping The granulated material obtained in step 7 is pressed into shape with a pressing pressure of 110 MPa. Step 9, Sintering: The green blank formed in step 8 is sintered at a temperature of 1000-1120℃ for more than 10 hours. After sintering, it is naturally cooled to room temperature to obtain the yttrium iron garnet ferrite material.

2. The method for preparing high dielectric constant, small linewidth yttrium iron garnet ferrite material according to claim 1, characterized in that, In step 2, during the first ball milling, the mass ratio of balls:material:deionized water:dispersant is 3.5:1:0.9:0.

002.

3. The method for preparing high dielectric constant and small linewidth yttrium iron garnet ferrite material according to claim 1, characterized in that, In step 4, during the secondary ball milling, the mass ratio of balls:material:deionized water is 3.5:1:0.9, and no dispersant is added.

4. The method for preparing high dielectric constant, small linewidth yttrium iron garnet ferrite material according to claim 1, characterized in that, In step 6, during the three ball milling processes, the mass ratio of balls:material:deionized water was 3.5:1:0.8, and no dispersant was added.

5. The method for preparing high dielectric constant, small linewidth yttrium iron garnet ferrite material according to claim 1, characterized in that, In step 9, the sintering process is a multi-stage sintering process. First, the temperature is raised from room temperature to 80°C in 30 minutes, then to 250°C in 2.5 hours, then to 400°C in 2.5 hours, and then raised to 200°C below the target sintering temperature at a rate of 2.5°C / min. The temperature is held for 3 hours, and finally the temperature is raised to the target sintering temperature in 4 hours. The temperature is held for more than 10 hours, and then the temperature is allowed to drop naturally after the holding period.

6. The method for preparing high dielectric constant, small linewidth yttrium iron garnet ferrite material according to claim 5, characterized in that, The target sintering temperature is 1000-1120℃.

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