Carbon ceramic composite material, preparation method and resistor disc

Abstract

This invention belongs to the field of electrical ceramics technology, and relates to a carbon ceramic composite material, its preparation method, and a resistor sheet. The composite material uses clay and kaolin as the ceramic matrix, introduces submicron graphite as the conductive phase, and incorporates nano-ceramic reinforcing powder. It is prepared through multi-stage wet mixing, spray drying granulation, and pressureless sintering under an inert atmosphere. The preparation method involves first pre-treating the material at medium temperature under vacuum to remove moisture and organic matter, followed by high-temperature sintering under inert gas protection to obtain a uniform and dense carbon ceramic composite matrix, on which electrodes and a high-resistivity layer are formed. Through the dispersion strengthening effect of the nano-ceramic reinforcing powder and the synergistic control of process parameters, the microstructure of the material is effectively improved, significantly increasing the compressive and flexural strength of the resistor sheet, reducing the risk of mechanical failure caused by electro-thermal-mechanical shocks during transportation and service, and making it suitable for use in high-voltage and ultra-high-voltage circuit breaker closing resistors.

Description

Technical Field

[0001] This invention belongs to the field of electrical ceramics, specifically relating to a carbon ceramic composite material, its preparation method, and a resistor sheet. Background Technology

[0002] In high-voltage and ultra-high-voltage power transmission and transformation systems, circuit breakers are key equipment for ensuring the safe opening and closing of power systems, and their operational reliability directly affects the safety and stability of the power grid. At the moment of circuit breaker closing, large inrush currents and overvoltages often occur in the system. If not effectively limited, these can easily cause impacts or even damage to the main circuit equipment, insulation systems, and related electrical components. Therefore, closing resistors are typically installed in high-voltage and ultra-high-voltage circuit breakers. By introducing a certain resistance value for a short period during the initial closing phase, current and voltage changes are suppressed, thereby ensuring the safe operation of the circuit breaker and the power grid system. The closing resistor operates for an extremely short time during connection and disconnection, but it needs to withstand high current density, temperature rise shocks, and complex mechanical stresses under instantaneous conditions, placing high demands on its material properties.

[0003] Carbon ceramic resistor materials have long been widely used in the field of high-voltage circuit breaker closing resistors due to their combination of certain conductivity, high temperature resistance, corrosion resistance, and relatively controllable cost. These materials typically use a ceramic phase as the structural framework and carbonaceous materials as the conductive phase, forming a multiphase composite structure through processes such as sintering, thereby achieving adjustable resistance and a certain mechanical support capacity. However, under current technological conditions, carbon ceramic composite resistor sheets still have some shortcomings in terms of structure and performance.

[0004] On the one hand, traditional carbon ceramic resistors are mostly prepared using simple mixing or single-process routes, resulting in limited uniformity of the conductive phase distribution at the microscale between the conductive phase and the ceramic matrix. This easily leads to the formation of enriched or depleted regions within the material, causing local performance differences. When the material is subjected to thermal shock, electrical shock, or mechanical vibration during actual use, these non-uniform regions can easily become stress concentration sources, inducing the generation and propagation of microcracks. On the other hand, the ceramic matrix itself has a certain degree of brittleness. If the microstructure of traditional carbon ceramic composite materials is not sufficiently dense or the pore structure is not ideally controlled during sintering, it will also weaken its overall load-bearing capacity, causing the resistor to break or experience performance degradation during transportation, installation, or repeated switching impacts.

[0005] Furthermore, in the preparation process of existing carbon ceramic resistance materials, the sintering atmosphere and heating regime have a significant impact on the internal structure of the material. If the organic components are not sufficiently removed or the conductive phase undergoes adverse changes at high temperatures, abnormal pores or micro-defects may form within the material, thereby affecting its mechanical properties and service stability. In practical engineering applications, mechanical failure of the closing resistor not only affects the normal closing function of the circuit breaker but may also lead to more serious equipment damage and operational risks.

[0006] Therefore, under the current technological background, how to improve the structural stability and mechanical properties of carbon ceramic composite resistor sheets while meeting resistance performance requirements, and reduce the probability of breakage or failure during transportation and use, has always been a technical problem of concern to those skilled in the art. Although various attempts have been made in the prior art to adjust the formula and optimize the process, it is still necessary to conduct further research on material composition design, microstructure uniformity control, and preparation process stability in order to obtain carbon ceramic composite resistor sheets with more stable and reliable overall performance. Summary of the Invention

[0007] The purpose of this invention is to solve the problem that existing carbon ceramic resistance sheets suffer from insufficient compressive and flexural strength due to uneven material structure, microscopic defects, and inherent brittleness, and are prone to mechanical failure during transportation and high-voltage circuit breaker closing.

[0008] The objective of this invention is achieved through the following technical solution: A carbon ceramic composite material, by mass parts, comprises the following raw materials: 30-50 parts clay, 40-60 parts kaolin, 3-10 parts submicron graphite, 1-5 parts dispersant, 1-5 parts polyvinyl alcohol, and 3-15 parts nano-ceramic reinforcing powder. After sintering, the nano-ceramic reinforcing powder is dispersed in the ceramic matrix to strengthen the structure of the carbon ceramic composite material.

[0009] Preferably, the nano-ceramic reinforcing powder is selected from at least one of silicon nitride, silicon carbide, and alumina.

[0010] Preferably, the submicron graphite forms a continuous conductive network structure in the ceramic matrix.

[0011] Based on the same inventive concept, the present invention also provides a method for preparing a carbon ceramic composite material, the method comprising the following steps: A mixed slurry was prepared by multi-stage wet mixing of clay, kaolin, submicron graphite, dispersant, polyvinyl alcohol and nano-ceramic reinforcing powder. The mixed slurry was spray-dried to obtain a mixed powder; The mixed powder is shaped into a green body and then sintered under pressureless conditions under inert gas protection to obtain the aforementioned carbon ceramic composite material.

[0012] Preferably, the multi-stage wet mixing includes: Clay, kaolin and nano-ceramic reinforcing powder are wet-mixed to form a ceramic material slurry; The dispersant is wet-mixed with submicron graphite to form a conductive material slurry; The ceramic material slurry, the conductive material slurry, and polyvinyl alcohol are mixed to obtain the mixed slurry.

[0013] Preferably, the pressureless sintering includes: The billet is vacuum heated to 600-700℃ and held for 1-2 hours. Under inert gas protection, reheat to 1200-1300℃ and hold for 2-4 hours.

[0014] Preferably, the inert gas includes nitrogen.

[0015] Preferably, the heating rate of the vacuum heating is less than 20°C / min.

[0016] Preferably, the heating rate of the reheating is less than 10°C / min.

[0017] Based on the same inventive concept, the present invention also provides a resistive sheet, comprising a matrix formed of the aforementioned carbon ceramic composite material, and an electrode layer and a high-resistivity layer disposed on the surface of the matrix.

[0018] Preferably, the electrode layer and the high-resistivity layer are disposed on opposite surfaces of the carbon ceramic composite matrix to carry current and limit inrush current during the closing process.

[0019] Preferably, the resistor element is used in the closing resistor assembly of a high-voltage or ultra-high-voltage circuit breaker.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention establishes a stable causal relationship between microstructure control and macroscopic performance improvement through the synergistic design of material composition and preparation process, thereby achieving significant and repeatable beneficial technical effects. Firstly, regarding material composition, clay and kaolin are used to construct the ceramic matrix framework. These raw materials can form a continuous and stable inorganic network structure during high-temperature sintering, providing the resistor sheet with basic shape retention and load-bearing capacity. Simultaneously, submicron-sized graphite is introduced as a conductive phase. Its particle size matches that of the ceramic particles, which is beneficial for forming continuous and uniform conductive pathways within the matrix, thus theoretically avoiding localized imbalances in electrical and thermal properties caused by conductive phase agglomeration.

[0021] Furthermore, this invention introduces a certain proportion of nano-ceramic reinforcing powder, which exists in a dispersed manner in the ceramic matrix and its grain boundary region. These nanoparticles can pin the grain boundaries and inhibit abnormal grain growth during the sintering process, thereby improving the integrity and density of the matrix structure at the microscopic level. This effectively disperses the external load when subjected to stress, significantly improving the compressive strength and flexural strength of the material.

[0022] At the manufacturing process level, this invention employs a multi-stage wet mixing method to process different functional components stepwise. By preparing the ceramic phase, conductive phase, and binder system into slurries and thoroughly mixing them under liquid phase conditions, highly uniform dispersion of each component at the microscale is achieved. This process fundamentally reduces the risk of component stratification and local enrichment caused by direct dry mixing of powders, laying the foundation for uniform microstructure evolution during subsequent sintering. Subsequently, a spray drying process transforms the mixed slurry into granulated powder with uniform particle size and good flowability, effectively improving the filling consistency and green body density distribution during molding, thereby reducing the possibility of internal stress and structural defects after sintering.

[0023] During the sintering stage, this invention employs a pressureless sintering process involving vacuum followed by inert atmosphere protection. Preheating and holding in the low-to-medium temperature range allows residual moisture and organic components in the green body to be fully expelled, preventing their rapid decomposition at high temperatures and the formation of abnormal pores or microcracks. Subsequently, high-temperature sintering is completed in an inert gas environment, effectively suppressing the oxidation and degradation of the conductive phase and ensuring the continuity and stability of the conductive network. From the perspective of material formation mechanism, this staged sintering method promotes uniform grain growth and controllable evolution of the pore structure, resulting in a more balanced stress distribution within the composite material. The carbon-ceramic composite matrix obtained in this way is less prone to localized stress concentration or rapid crack propagation when subjected to multiple electrical, thermal, and mechanical impacts.

[0024] Based on the above technical features and mechanisms of action, the carbon ceramic composite resistive sheet prepared by this invention significantly improves the compressive and flexural strength of the material while maintaining its existing resistive performance, reducing the risk of mechanical failure during transportation, installation, and repeated closing impacts. This technical effect has been verified by performance test results from examples and comparative examples, demonstrating the overall improvement in material structural stability and service reliability of this invention. It is suitable for application in high-voltage and ultra-high-voltage circuit breaker closing resistor scenarios where high safety and reliability requirements are present. Detailed Implementation

[0025] The technical solution will be further described below with reference to specific embodiments to help understand the content of the present invention.

[0026] Example 1 The present invention provides a carbon ceramic composite material, wherein the raw material composition of the carbon ceramic composite material comprises, by mass parts: 30-50 parts of clay, 40-60 parts of kaolin, 3-10 parts of submicron graphite, 1-5 parts of dispersant, 1-5 parts of polyvinyl alcohol, and 3-15 parts of nano-ceramic reinforcing powder.

[0027] The nano-ceramic reinforcing powder is at least one of silicon nitride, silicon carbide, and aluminum oxide.

[0028] In a specific embodiment, the raw material composition, by mass parts, is shown in Table 1: Table 1: Raw material ratios for Example 1

[0029] The preparation process of the carbon ceramic composite material and the resistor sheet in this embodiment includes the following steps: S1. A mixed slurry is prepared by multi-stage wet mixing of clay, kaolin, dispersant, submicron graphite and polyvinyl alcohol; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The blank is subjected to pressureless sintering under inert gas protection, vacuum heating at <20℃ / min to 600℃, holding for 2 hours, and then heated again under nitrogen protection at <10℃ / min to 1200℃, holding for 4 hours, and then cooled with the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0030] The carbon ceramic composite material of this embodiment is composed of clay, kaolin, submicron graphite, dispersant, polyvinyl alcohol and nano-ceramic reinforcing powder. By introducing nano-ceramic reinforcing powder, it plays a role in dispersion strengthening and second phase strengthening, thereby enhancing the strength of the carbon ceramic composite material skeleton.

[0031] Example 2 This invention also provides a method for preparing a carbon ceramic composite resistive sheet, comprising the following steps: A mixed slurry was prepared by multi-stage wet mixing of clay, kaolin, dispersant, submicron graphite, polyvinyl alcohol and nano-ceramic reinforced powder; The mixed slurry is prepared into a mixed powder using a spray drying device; Weigh the mixed powder according to the required powder mass, put it into the molding mold, and perform pressureless sintering under inert gas protection to obtain a carbon ceramic composite matrix. Using the carbon ceramic composite material as a matrix, electrodes and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite resistive sheet.

[0032] The multi-stage wet mixing process for preparing the mixed slurry specifically includes the following steps: S1. Clay, kaolin and nano-ceramic reinforcing powder are wet-mixed with distilled water to obtain ceramic material slurry; S2. The dispersant and submicron graphite are wet-mixed with distilled water to obtain a conductive material slurry; S3. The ceramic material slurry, the conductive material slurry, and the polyvinyl alcohol are wet-mixed to obtain a mixed slurry.

[0033] The pressureless sintering under atmosphere protection specifically includes: vacuum heating the formed green body to 600~700℃, holding it at that temperature for 1~2 hours, and then heating it again under inert gas protection to 1200~1300℃ for a second holding for 2~4 hours.

[0034] Preferably, the inert protective gas is nitrogen.

[0035] The carbon ceramic composite material of this embodiment has the following raw material composition by mass parts: Table 2: Table 2: Raw material ratios for Example 2

[0036] The preparation process of the carbon ceramic composite material and the resistor sheet in this embodiment includes the following steps: S1. A mixed slurry is prepared by multi-stage wet mixing of clay, kaolin, dispersant, submicron graphite, polyvinyl alcohol and nano-silicon carbide; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The blank is subjected to pressureless sintering under inert gas protection, vacuum heating at <20℃ / min to 600℃, holding for 2 hours, and then heated again under nitrogen protection at <10℃ / min to 1200℃, holding for 4 hours, and then cooled with the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0037] The method for preparing carbon ceramic composite resistive sheets provided in this invention employs multi-stage wet powder mixing and pressureless sintering under inert gas protection, which improves the quality of carbon ceramic composite materials in terms of both material microstructure uniformity and sintering stress control. During sintering, the uniformly mixed powder exhibits similar composition and similar grain growth processes in different regions, reducing the likelihood of localized stress. Inert gas protection during sintering effectively reduces the oxidation of the conductive phase, while vacuum heating to 600-700℃ facilitates the removal of moisture and organic matter from the powder, preventing the formation of abnormal pores and microcracks during grain growth, thereby improving the compressive and flexural strength of the carbon ceramic composite material.

[0038] Example 3 This embodiment provides a carbon ceramic composite material, the raw material composition of which is shown in Table 3 by mass parts: Table 3: Raw material ratios for Example 3

[0039] The preparation process of the carbon ceramic composite material and the resistor sheet in this embodiment includes the following steps: S1. A mixed slurry is prepared by multi-stage wet mixing of clay, kaolin, dispersant, submicron graphite, polyvinyl alcohol and nano-silicon nitride; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The blank is subjected to pressureless sintering under inert gas protection, vacuum heating at <20℃ / min to 600℃, holding for 2 hours, and then heated again under nitrogen protection at <10℃ / min to 1200℃, holding for 4 hours, and then cooled with the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0040] Example 4 This embodiment provides a carbon ceramic composite material, the raw material composition of which is shown in Table 4 by mass parts: Table 4: Raw material ratios for Example 4

[0041] The preparation process of the carbon ceramic composite material and the resistor sheet in this embodiment includes the following steps: S1. A mixed slurry is prepared by multi-stage wet mixing of clay, kaolin, dispersant, submicron graphite, polyvinyl alcohol and nano-silicon carbide; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The blank is subjected to pressureless sintering under inert gas protection, vacuum heating at <20℃ / min to 600℃, holding for 2 hours, and then heated again under nitrogen protection at <10℃ / min to 1300℃, holding for 3 hours, and then cooled with the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0042] Example 5 This embodiment provides a carbon ceramic composite material, the raw material composition of which is shown in Table 5 by mass parts: Table 5: Raw material ratios for Example 5

[0043] The preparation process of the carbon ceramic composite material and the resistor sheet in this embodiment includes the following steps: S1. A mixed slurry is prepared by multi-stage wet mixing of clay, kaolin, dispersant, submicron graphite, polyvinyl alcohol and nano-silicon carbide; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The blank is subjected to pressureless sintering under inert gas protection, vacuum heating at <20℃ / min to 600℃, holding for 2 hours, and then heated again under nitrogen protection at <10℃ / min to 1300℃, holding for 3 hours, and then cooled with the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0044] Example 6 This embodiment provides a carbon ceramic composite material, the raw material composition of which is shown in Table 6 by mass parts: Table 6: Raw material ratios for Example 6

[0045] The preparation process of the carbon ceramic composite material and the resistor sheet in this embodiment includes the following steps: S1. A mixed slurry is prepared by multi-stage wet mixing of clay, kaolin, dispersant, submicron graphite, polyvinyl alcohol and nano alumina; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The blank is subjected to pressureless sintering under inert gas protection, vacuum heating at <20℃ / min to 700℃, holding for 1 hour, and then heated again under nitrogen protection at <10℃ / min to 1300℃, holding for 2 hours, and then cooled with the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0046] Example 7 This embodiment provides a carbon ceramic composite material, the raw material composition of which is shown in Table 7 by mass parts: Table 7: Raw material ratios for Example 7

[0047] The preparation process of the carbon ceramic composite material and the resistor sheet in this embodiment includes the following steps: S1. A mixed slurry is prepared by multi-stage wet mixing of clay, kaolin, dispersant, submicron graphite, polyvinyl alcohol and nano-silicon nitride; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The blank is subjected to pressureless sintering under inert gas protection, vacuum heating at <20℃ / min to 700℃, holding for 1 hour, and then heated again under nitrogen protection at <10℃ / min to 1300℃, holding for 2 hours, and then cooled with the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0048] Examples 8-12 The differences between Examples 8-12 and Example 2 are shown in Table 8 below: Table 8: Specific process parameters for Examples 8-12

[0049] Comparative Example 1 The raw material composition of the carbon ceramic composite material in this comparative example, in parts by mass, is shown in Table 9: Table 9: Raw material ratio of Comparative Example 1

[0050] The preparation process of the carbon ceramic composite material and the resistor sheet in this comparative example includes the following steps: S1. Prepare a mixed slurry by mixing clay, kaolin, dispersant, submicron graphite and polyvinyl alcohol; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The green body is subjected to nitrogen protection and pressureless sintering. The temperature is increased to 1200℃ at <10℃ / min, held for 4 hours and then cooled in the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0051] Comparative Example 2 The raw material composition of the carbon ceramic composite material in this comparative example, in parts by mass, is shown in Table 10: Table 10: Raw material ratio of Comparative Example 2

[0052] The preparation process of the carbon ceramic composite material and the resistor sheet in this comparative example includes the following steps: S1. Prepare a mixed slurry by mixing clay, kaolin, dispersant, submicron graphite and polyvinyl alcohol; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The green body is subjected to nitrogen protection and pressureless sintering. The temperature is increased to 1200℃ at <10℃ / min, held for 2 hours and then cooled in the furnace to obtain carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0053] Comparative Example 3 The raw material composition of the carbon ceramic composite material in this comparative example, in parts by mass, is shown in Table 11: Table 11: Raw material ratio of Comparative Example 3

[0054] The preparation process of the carbon ceramic composite material and the resistor sheet in this comparative example includes the following steps: S1. Prepare a mixed slurry by mixing clay, kaolin, dispersant, submicron graphite and polyvinyl alcohol; S2. The mixed slurry is prepared into a mixed powder using a spray drying device; S3. Weigh the mixed powder according to the required powder mass and put it into the molding mold to form a blank; S4. The green body is subjected to nitrogen protection and pressureless sintering. The temperature is increased to 1300℃ at a rate of <10℃ / min, held for 2 hours and then cooled in the furnace to obtain a carbon ceramic composite material. S5. Using the carbon ceramic composite material as a matrix, an electrode and a high-resistivity layer are coated on the surface of the matrix to obtain a carbon ceramic composite material resistor sheet.

[0055] Experimental Example The compressive strength test was conducted in accordance with GB / T 1964-2023 "Test Method for Room Temperature Compressive Strength of Porous Ceramics".

[0056] The bending strength test was conducted in accordance with the provisions of GB / T 1965-2023 "Test Method for Bending Strength of Porous Ceramics at Room Temperature".

[0057] The samples prepared in Examples 1-7 and Comparative Examples 1-3 were selected for compressive strength and flexural strength tests, and the results are shown in Table 12 below.

[0058] Table 12: Test Data Comparison Table

[0059] As can be seen from the table above, compared with Comparative Example 1, the compressive strength and flexural strength of the resistor sheet prepared in Example 1 are slightly improved; compared with Comparative Examples 1 to 3, the compressive strength and flexural strength of the composite materials prepared in Examples 2 to 7 are significantly improved. This shows that by optimizing the formulation and / or preparation process of the carbon ceramic composite material, the present invention can obtain a carbon ceramic composite resistor sheet with high compressive strength and flexural strength.

[0060] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of the claims of the present invention.

Claims

1. A carbon ceramic composite material, characterized by, The raw materials of the carbon ceramic composite material, by mass parts, include: 30-50 parts clay, 40-60 parts kaolin, 3-10 parts submicron graphite, 1-5 parts dispersant, 1-5 parts polyvinyl alcohol, and 3-15 parts nano-ceramic reinforcing powder.

2. A carbon ceramic composite material as claimed in claim 1, wherein, The nano-ceramic reinforcing powder is selected from at least one of silicon nitride, silicon carbide, and alumina.

3. A carbon ceramic composite material as claimed in claim 1, wherein, The submicron graphite forms a continuous conductive network structure in the ceramic matrix.

4. A method of producing a carbon ceramic composite material, characterized by, Includes the following steps: A mixed slurry was prepared by multi-stage wet mixing of clay, kaolin, submicron graphite, dispersant, polyvinyl alcohol and nano-ceramic reinforcing powder. The mixed slurry was spray-dried to obtain a mixed powder; The mixed powder is formed into a green body and sintered without pressure under inert gas protection to obtain a carbon ceramic composite material as described in any one of claims 1-3. After sintering, the nano-ceramic reinforcing powder is dispersed in the ceramic matrix to strengthen the structure of the carbon ceramic composite material.

5. The production method according to claim 4, wherein The multi-stage wet mixing includes: Clay, kaolin and nano-ceramic reinforcing powder are wet-mixed to form a ceramic material slurry; The dispersant is wet-mixed with submicron graphite to form a conductive material slurry; The ceramic material slurry, the conductive material slurry, and polyvinyl alcohol are mixed to obtain the mixed slurry.

6. The production method according to claim 4, wherein The pressureless sintering includes: The billet is vacuum heated to 600-700℃ and held for 1-2 hours. Under inert gas protection, reheat to 1200-1300℃ and hold for 2-4 hours.

7. The production method according to claim 6, wherein The inert gas includes nitrogen.

8. The preparation method according to claim 6, characterized in that, The heating rate of the vacuum heating is less than 20°C / min.

9. The production method according to claim 6, characterized by, The reheating rate is less than 10°C / min.

10. A resistance chip, characterized by It includes a matrix formed of the carbon ceramic composite material according to any one of claims 1 to 3, and an electrode layer and a high-resistivity layer disposed on the surface of the matrix.

11. The resistor disc according to claim 10, wherein The electrode layer and the high-resistivity layer are disposed on opposite surfaces of the carbon ceramic composite matrix to carry current and limit inrush current during the closing process.

12. The chip of claim 10 wherein, The resistor element is used as the closing resistor assembly in high-voltage or ultra-high-voltage circuit breakers.

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