High-performance zinc oxide piezoresistor ceramic material, preparation method thereof and zinc oxide piezoresistor

Abstract

The invention provides a high-performance zinc oxide piezoresistor ceramic material, a preparation method thereof and a zinc oxide piezoresistor. The ceramic material comprises the following components in percentage by mass: 85-90% of large-particle ZnO, 1-6% of an auxiliary material and 4-14% of a modified additive. The auxiliary material is NixCoyMnZ (OH) 2 with the specific surface area larger than 20 m < 2 > / g, the value ranges of x, y and z are all 0.1-0.8, and x + y + z = 1. The preparation method comprises the following steps: carrying out wet ball milling on an auxiliary material and a modified additive to obtain mixed slurry, adding the mixed slurry into large-particle ZnO, mixing, and drying to obtain the high-performance zinc oxide piezoresistor ceramic material with good dispersibility, uniformity and stability. The ZnO of the material forms a coating layer, and the piezoresistor obtained by pressing can be sintered into ceramic in an air atmosphere in a wide sintering temperature range of 1020-1250 DEG C, has good surge performance, has a voltage gradient of more than 190 V / mm, can pass a 385AC loading * 125 DEG C * 1000 H test, and has a wide market application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pressure sensitive resistance ceramic materials, and particularly relates to a high-performance zinc oxide pressure sensitive resistance ceramic material, a preparation method thereof and a zinc oxide pressure sensitive resistor. BACKGROUND

[0002] With the rapid development of the fields of electric power, electronics, new energy and high-end manufacturing, overvoltage protection scenarios of 'high energy, high frequency and wide temperature range' are used more and more frequently. Therefore, higher requirements are put forward for the performance of the pressure sensitive resistance element.

[0003] The pressure sensitive resistance ceramic material is a ceramic material composed of multiple components. The current raw material process is usually to mix the raw materials of the pressure sensitive resistance ceramic material in multiple components once and to sinter once. However, when the raw material process is used, the specific gravity, morphology and surface state of the materials are greatly different, so that the mixing is difficult and the uniformity is difficult to guarantee. SUMMARY

[0004] The present application aims to provide a high-performance zinc oxide pressure sensitive resistance ceramic material, which has good dispersibility, uniformity and stability.

[0005] Another object of the present application is to provide a preparation method of the high-performance zinc oxide pressure sensitive resistance ceramic material, which refines the auxiliary material and the modified additive in advance, and mixes the large particle ZnO to prepare the high-performance zinc oxide pressure sensitive resistance ceramic material. The method is simple in operation and controllable in parameters, and is suitable for industrial large-scale production.

[0006] A third object of the present application is to provide a zinc oxide pressure sensitive resistor and a preparation method thereof. The pressure sensitive resistor can be sintered at 1020-1250℃, and has a wide sintering temperature.

[0007] The technical problem of the present application is solved by using the following technical scheme.

[0008] The present application provides a high-performance zinc oxide pressure sensitive resistance ceramic material, which comprises 85-90% large particle ZnO, 1-6% auxiliary material and 4-14% modified additive by mass fraction. The auxiliary material is NiCoMn(OH)2 with a specific surface area greater than 20m2 / g, wherein the value range of x, y and z is 0.1-0.8, and x+y+z=1. 2 x y Z (OH)2, wherein the value range of x, y and z is 0.1-0.8, and x+y+z=1.

[0009] The present application provides a preparation method of the high-performance zinc oxide pressure sensitive resistance ceramic material, which comprises the following steps:

[0010] ​​​S1. The modified additive and the auxiliary material are subjected to wet ball milling to obtain a mixed slurry;

[0011] S2. The large-particle ZnO and the mixed slurry are wet-mixed and then dried to obtain the high-performance zinc oxide varistor ceramic material.

[0012] This invention proposes a method for preparing a zinc oxide varistor, comprising the following steps:

[0013] The high-performance zinc oxide varistor ceramic material is pressed into a blank and sintered at 1020℃~1250℃ to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 650℃~680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, a zinc oxide varistor is obtained.

[0014] This invention proposes a zinc oxide varistor, which is prepared according to the above-described method.

[0015] The beneficial effects of the high-performance zinc oxide varistor ceramic material and its preparation method, as well as the zinc oxide varistor of the present invention, are as follows:

[0016] 1. This invention uses large-particle ZnO as the main material, taking advantage of its large particle size, small specific surface area, and low electrostatic adsorption between large ZnO particles. Simultaneously, it minimizes grinding to reduce damage to the ZnO particle structure. Then, pre-ground large-surface-area modifiers and auxiliary materials are used for modification and doping. The refined additives adhere well to the large-particle ZnO, forming a good network between the grains and spinel during the subsequent sintering and cooling process. This results in a high-performance zinc oxide varistor ceramic material with excellent dispersibility, uniformity, and stability.

[0017] 2. Employ a large specific surface area (greater than 20m²) 2 / g) of Ni x Co y Mn Z (OH)2 can ensure that Ni-Co-Mn and ZnO form the Zn(Ni,Co,Mn)2O4 spinel phase, which is concentrated at the intersection of three or more ZnO grains. It can also be embedded in the ZnO grains or squeezed between two ZnO grains, thus inhibiting the growth of ZnO grains and ensuring the performance of the varistor.

[0018] 3. The ZnO ceramic material of the present invention will form a coating layer. The varistor obtained by pressing can be sintered into ceramic in air atmosphere at a wide sintering temperature range of 1020 to 1250°C. It has good surge performance, with a voltage gradient of >190V / mm. It can pass the 385AC loading * 125°C * 1000H test and has broad market application prospects. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0020] The following provides a detailed description of the high-performance zinc oxide varistor ceramic material, its preparation method, and the zinc oxide varistor according to embodiments of the present invention.

[0021] This invention provides a high-performance zinc oxide varistor ceramic material, comprising, by mass fraction, 85-90% large-particle ZnO, 1-6% auxiliary materials, and 4-14% modifying additives, wherein the auxiliary materials have a specific surface area greater than 20 m². 2 / g of Ni x Co y Mn Z (OH)₂, where x, y, and z all range from 0.1 to 0.8, and x + y + z = 1. The varistor ceramic material of this invention uses large-particle ZnO as the core, supplemented with certain modified additives and auxiliary materials, exhibiting good dispersibility, uniformity, and stability. Its voltage gradient is >190V / mm, and it can pass the 385AC loading * 125℃ * 1000H test.

[0022] Furthermore, in a preferred embodiment of the present invention, the particle size D50 of the large ZnO particles is 1.5 to 2.5 μm.

[0023] Furthermore, in a preferred embodiment of the present invention, the modified additive is selected from three or more of bismuth oxide, silicon dioxide, antimony oxide, boron oxide, chromium oxide, magnesium carbonate, aluminum oxide, barium carbonate, strontium carbonate, and silver nitrate.

[0024] Further, in a preferred embodiment of the present invention, the high-performance zinc oxide varistor ceramic material, by mass fraction, comprises 1.0–6.0% bismuth oxide, 0.01–0.2% silicon dioxide, 1.0–6.0% antimony oxide, 0.03–0.3% boron oxide, 0.2–5% chromium oxide, 0.01–0.3% magnesium carbonate, 0.01–0.3% aluminum oxide, 0.01–0.3% barium carbonate, 0.01–0.3% strontium carbonate, and 0.01–0.2% silver nitrate.

[0025] This invention also provides a method for preparing high-performance zinc oxide varistor ceramic materials, comprising the following steps:

[0026] S1. The modified additives and the auxiliary materials are subjected to wet ball milling to obtain a mixed slurry.

[0027] Furthermore, in a preferred embodiment of the present invention, the weight ratio of the modified additive and the auxiliary material to water is 1:1 to 2.

[0028] Furthermore, in a preferred embodiment of the present invention, the particle size D50 of the mixed slurry is 0.05 to 0.15 μm.

[0029] S2. The large-particle ZnO and the mixed slurry are wet-mixed (without wet ball milling), and then dried to obtain the high-performance zinc oxide varistor ceramic material.

[0030] The combination of increased ZnO particle size and refined auxiliary materials effectively solves the problems of high mixing difficulty and difficulty in ensuring uniformity caused by the single mixing and sintering of multiple components in the raw material process. This invention avoids the defects of small particles and strong electrostatic adsorption by pre-refining auxiliary materials and modifying additives and mixing them with large ZnO particles. Then, high-speed mixing using a homogenizer achieves uniform mixing, ensuring the homogeneity of subsequent phases.

[0031] Using a large specific surface area (greater than 20m²) 2 / g) of Ni x Co y Mn Z(OH)2 ensures that Ni-Co-Mn and ZnO form the Zn(Ni,Co,Mn)2O4 spinel phase, concentrated at the intersection of three or more ZnO grains. It can be embedded within ZnO grains or squeezed between two ZnO grains, inhibiting ZnO grain growth and thus ensuring the performance of the varistor. Furthermore, because the refined auxiliary material adheres well to large ZnO particles, it forms a good network between the grains and spinel during the later sintering and cooling process. This buffers stress defects caused by asynchronous sintering of different components, reduces the concentration of grain and grain boundary cracks and point / line defects, and ensures the product's moisture resistance and current flow, thereby achieving high performance.

[0032] Furthermore, in a preferred embodiment of the present invention, the weight ratio of the large-particle ZnO and the mixed slurry to water is 1:0.6 to 1.

[0033] This invention provides a method for preparing a zinc oxide varistor, comprising the following steps:

[0034] The high-performance zinc oxide varistor ceramic material is pressed into a blank and sintered at 1020℃~1250℃ to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 650℃~680℃, a zinc oxide varistor chip is obtained. This chip is then soldered and encapsulated to obtain the zinc oxide varistor. Sintering is carried out in an air atmosphere for 3.4~4.5 hours. Preferably, the sintering time is 4 hours.

[0035] The high-performance zinc oxide varistor ceramic material of the present invention can be sintered into ceramic within a wide sintering temperature range of 1020 to 1250°C, exhibiting excellent surge performance with a voltage gradient >190V / mm. It can pass the 385AC loading * 125°C * 1000H test and has broad market application prospects.

[0036] This invention provides a zinc oxide varistor, which is prepared according to the above-described method. The varistor of this invention has a wide sintering temperature range.

[0037] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0038] Example 1

[0039] This embodiment provides a high-performance zinc oxide varistor ceramic material, comprising 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modifying additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in Formulation C1 of Table 1; the proportions of the auxiliary materials are shown in A1 of Table 2; and the proportions of the modifying additives are shown in B1 of Table 3. This high-performance zinc oxide varistor ceramic material is prepared according to the following steps:

[0040] (1) The auxiliary materials and modified additives are wet ball-milled to a particle size value of D50 = 0.05~0.15um to obtain a mixed slurry; wherein the weight ratio of the auxiliary materials and modified additives to water is 1:2.

[0041] (2) The large-particle ZnO and the mixed slurry are wet-mixed (without wet ball milling), and then dried to obtain a high-performance zinc oxide varistor ceramic material composition. The weight ratio of the material composed of large-particle ZnO and the mixed slurry to water is 1:1.

[0042] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0043] The high-performance zinc oxide varistor ceramic material obtained in Example 1 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1160℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0044] Table 1 Formulation of High-Performance Zinc Oxide Varistor Ceramic Material

[0045]

[0046]

[0047] Table 2. Auxiliary material ratios for high-performance zinc oxide varistor ceramic materials.

[0048]

[0049] Table 3. Proportioning of Additives for Modifying High-Performance Zinc Oxide Varistor Ceramic Materials

[0050]

[0051] Example 2

[0052] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0053] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C2 of Table 1; the formulation of the auxiliary materials is shown in A2 of Table 2; and the formulation of the modified additives is shown in B4 of Table 3.

[0054] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0055] The high-performance zinc oxide varistor ceramic material obtained in Example 2 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1230℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0056] Example 3

[0057] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0058] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C3 of Table 1; the formulation of the auxiliary materials is shown in A1 of Table 2; and the formulation of the modified additives is shown in B5 of Table 3.

[0059] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0060] The high-performance zinc oxide varistor ceramic material obtained in Example 3 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1230℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0061] Example 4

[0062] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0063] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C4 of Table 1; the formulation of the auxiliary materials is shown in A2 of Table 2; and the formulation of the modified additives is shown in B1 of Table 3.

[0064] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0065] The high-performance zinc oxide varistor ceramic material obtained in Example 4 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1050℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0066] Example 5

[0067] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0068] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C5 of Table 1; the formulation of the auxiliary materials is shown in A2 of Table 2; and the formulation of the modified additives is shown in B3 of Table 3.

[0069] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0070] The high-performance zinc oxide varistor ceramic material obtained in Example 5 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1230℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0071] Example 6

[0072] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0073] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C6 of Table 1; the formulation of the auxiliary materials is shown in A2 of Table 2; and the formulation of the modified additives is shown in B5 of Table 3.

[0074] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0075] The high-performance zinc oxide varistor ceramic material obtained in Example 6 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1240℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0076] Example 7

[0077] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0078] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C7 of Table 1; the formulation of the auxiliary materials is shown in A3 of Table 2; and the formulation of the modified additives is shown in B2 of Table 3.

[0079] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0080] The high-performance zinc oxide varistor ceramic material obtained in Example 7 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1240℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0081] Example 8

[0082] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0083] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C8 of Table 1; the formulation of the auxiliary materials is shown in A3 of Table 2; and the formulation of the modified additives is shown in B5 of Table 3.

[0084] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0085] The high-performance zinc oxide varistor ceramic material obtained in Example 8 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1140℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0086] Example 9

[0087] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0088] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C9 of Table 1; the formulation of the auxiliary materials is shown in A4 of Table 2; and the formulation of the modified additives is shown in B4 of Table 3.

[0089] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0090] The high-performance zinc oxide varistor ceramic material obtained in Example 9 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1240℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0091] Example 10

[0092] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0093] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C10 of Table 1; the formulation of the auxiliary materials is shown in A4 of Table 2; and the formulation of the modified additives is shown in B5 of Table 3.

[0094] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0095] The high-performance zinc oxide varistor ceramic material obtained in Example 10 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1210℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0096] Example 11

[0097] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0098] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C11 of Table 1; the formulation of the auxiliary materials is shown in A5 of Table 2; and the formulation of the modified additives is shown in B2 of Table 3.

[0099] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0100] The high-performance zinc oxide varistor ceramic material obtained in Example 11 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1210℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0101] Example 12

[0102] This embodiment provides a high-performance zinc oxide varistor ceramic material, which differs from Embodiment 1 in that:

[0103] It includes 100g of large-particle ZnO, 3g of auxiliary materials, and 12g of modified additives. The formulation of the high-performance zinc oxide varistor ceramic material is shown in formulation C12 of Table 1; the formulation of the auxiliary materials is shown in A5 of Table 2; and the formulation of the modified additives is shown in B5 of Table 3.

[0104] This embodiment also provides a zinc oxide varistor, which is manufactured according to the following steps:

[0105] The high-performance zinc oxide varistor ceramic material obtained in Example 12 was pressed into a diameter of Ф16.4 mm, a thickness of 3.65 mm, and a density of 3.0 g / cm³. 3 The blank is then heated to 1210℃ in air and sintered for 4 hours to obtain a zinc oxide varistor ceramic sheet. Then, a Ф11mm silver electrode is printed on it, and after reduction at 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, the finished zinc oxide varistor is obtained.

[0106] Experimental Example 1

[0107] This test example performs electrical performance tests on the zinc oxide varistors in Examples 1 to 12, respectively. The specific steps are as follows:

[0108] The zinc oxide varistors in Examples 1 to 12 were tested for varistor parameters on a CJ1001 varistor tester, and their current carrying capacity was tested using an M20 surge generator. Their electrical performance was tested using an AT2181-020-G lightning strike combined wave tester, a Y / WJS-150L high and low temperature alternating thermal test equipment, and a 2ms pulse test equipment. The electrical performance test results are shown in Table 4.

[0109] Table 4 Electrical Performance Tests

[0110]

[0111]

[0112] As can be seen from Table 4, after the zinc oxide varistor of the present invention is sintered at a temperature of 1020 to 1250°C, the product achieves high current capacity, strong combined wave characteristics, high energy tolerance, and high reliability under long-term AC loading at high temperature.

[0113] The embodiments described above are some, but not all, embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A high-performance zinc oxide varistor ceramic material, characterized in that, By mass fraction, it comprises 85–90% large-particle ZnO, 1–6% auxiliary materials, and 4–14% modified additives, wherein the auxiliary materials have a specific surface area greater than 20 m². 2 / g of Ni x Co y Mn Z (OH)2, where x, y, and z all range from 0.1 to 0.8, and x+y+z=1.

2. The high-performance zinc oxide varistor ceramic material according to claim 1, characterized in that, The particle size D50 of the large ZnO particles is 1.5 to 2.5 μm.

3. The high-performance zinc oxide varistor ceramic material according to claim 1, characterized in that, The modified additive is selected from three or more of the following: bismuth oxide, silicon dioxide, antimony oxide, boron oxide, chromium oxide, magnesium carbonate, aluminum oxide, barium carbonate, strontium carbonate, and silver nitrate.

4. The high-performance zinc oxide varistor ceramic material according to claim 3, characterized in that, By mass fraction, the high-performance zinc oxide varistor ceramic material contains 1.0–6.0% bismuth oxide, 0.01–0.2% silicon dioxide, 1.0–6.0% antimony oxide, 0.03–0.3% boron oxide, 0.2–5% chromium oxide, 0.01–0.3% magnesium carbonate, 0.01–0.3% aluminum oxide, 0.01–0.3% barium carbonate, 0.01–0.3% strontium carbonate, and 0.01–0.2% silver nitrate.

5. A method for preparing a high-performance zinc oxide varistor ceramic material as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S1. The modified additive and the auxiliary material are subjected to wet ball milling to obtain a mixed slurry; S2. The large-particle ZnO and the mixed slurry are wet-mixed and then dried to obtain the high-performance zinc oxide varistor ceramic material.

6. The preparation method according to claim 5, characterized in that, In step S1, the weight ratio of the modified additive and the auxiliary material to water is 1:1 to 2.

7. The preparation method according to claim 5, characterized in that, In step S1, the particle size D50 of the mixed slurry is 0.05 to 0.15 μm.

8. The manufacturing process according to claim 6, characterized in that, In step S2, the weight ratio of the large-particle ZnO and the mixed slurry to water is 1:0.6 to 1.

9. A method for preparing a zinc oxide varistor, characterized in that, Includes the following steps: The high-performance zinc oxide varistor ceramic material as described in any one of claims 1 to 4 is pressed into a blank and sintered at 1020℃ to 1250℃ to obtain a zinc oxide varistor ceramic sheet. Then, silver electrodes are printed on it, and after reduction at 650℃ to 680℃, a zinc oxide varistor chip is obtained. After welding and encapsulation, a zinc oxide varistor is obtained.

10. A zinc oxide varistor, characterized in that, It is prepared according to the preparation method described in claim 9.

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