High-voltage switch contact and preparation method and application thereof

Abstract

The invention relates to a high-voltage switch contact and a preparation method and application thereof. The high-voltage switch contact comprises a copper substrate, a protective coating is arranged on the surface of the copper substrate; and the protective coating is made of a silver-copper oxide composite material. The high-voltage switch contact has relatively good electrical conductivity, wear resistance and heat-conducting property, and can be prepared by a relatively simple preparation process.

Description

Technical Field

[0001] This application relates to the field of switch contact technology, and in particular to high-voltage switch contacts, their manufacturing methods, and applications. Background Technology

[0002] In high-voltage electrical systems, high-voltage switch contacts are crucial components, responsible for connecting, carrying, and disconnecting circuits. Their performance directly impacts the safe and stable operation of the entire high-voltage power system. Traditionally, high-voltage switch contacts are made of pure copper. Pure copper has good electrical and thermal conductivity, meeting basic circuit transmission requirements. However, under high-voltage, high-current, and frequent operation conditions, the shortcomings of pure copper high-voltage switch contacts become increasingly apparent. Firstly, pure copper has low hardness and poor wear resistance, making it prone to wear during contact and disconnection. This increases surface roughness and contact resistance, leading to localized overheating, accelerating contact damage, and shortening its service life. Secondly, pure copper lacks sufficient resistance to arc erosion. When the contacts disconnect the circuit, a strong arc is generated. The high temperature of the arc melts and evaporates the surface of the pure copper contacts, forming molten metal droplets that splash. This not only causes material loss but can also lead to serious faults such as phase-to-phase short circuits, affecting the normal operation of the power system.

[0003] To improve the performance of pure copper contacts, silver plating technology can be used. Plating a layer of silver on the surface of the pure copper contact can improve its conductivity and resistance to arc erosion. Although pure silver coating has excellent conductivity, it still has many problems, such as its softness and poor wear resistance. Existing copper-based composite materials, such as copper-tungsten (CuW) alloys, although possessing high strength, hardness, and good arc erosion resistance, have complex manufacturing processes, requiring multiple steps such as high-temperature smelting and powder metallurgy, resulting in high energy consumption and high costs, making it difficult to meet the needs of large-scale, low-cost production. Therefore, there is an urgent need to develop a high-performance high-voltage switch contact with a simple manufacturing process. Summary of the Invention

[0004] Therefore, it is necessary to provide a high-voltage switch contact, its manufacturing method, and its application. The high-voltage switch contact of this application achieves a good balance of conductivity, wear resistance, and thermal conductivity, and can be manufactured through a relatively simple process. In other words, the high-voltage switch contact of this application has excellent performance and a simple manufacturing process.

[0005] In a first aspect, this application provides a high-voltage switch contact, including a copper substrate; a protective coating is disposed on the surface of the copper substrate; the material of the protective coating includes a silver-copper oxide composite material.

[0006] In some embodiments, the protective coating is a silver-copper oxide composite coating.

[0007] In some embodiments, the mass percentage of copper oxide in the protective coating is 3% to 8% of the total mass of the protective coating.

[0008] In some embodiments, the copper oxide phase in the protective coating is uniformly distributed in a semi-continuous framework within the silver matrix.

[0009] In some embodiments, the copper oxide in the protective coating accounts for 5% of the total mass of the protective coating.

[0010] Secondly, this application provides a method for manufacturing a high-voltage switch contact, comprising the following steps:

[0011] Provide copper substrate;

[0012] A mixed raw material is obtained by mixing silver raw material and copper oxide raw material. A protective coating is prepared by using the mixed raw material to sinter it onto the surface of the copper substrate by spark plasma sintering. The material of the protective coating includes a silver-copper oxide composite material.

[0013] In some embodiments, mixing silver raw material and copper oxide raw material to obtain a mixed raw material includes the following steps:

[0014] The silver raw material and the copper raw material were cleaned sequentially using alkaline solution and acid solution;

[0015] The cleaned silver and copper raw materials are ball-milled and mixed.

[0016] In some embodiments, the holding temperature of the discharge plasma sintering is 920℃~940℃, the holding time of the discharge plasma sintering is 25min~35min, and the holding pressure of the discharge plasma sintering is 19MPa~21MPa.

[0017] In some embodiments, the preparation of a protective coating on the surface of the copper substrate using the mixed raw materials by spark plasma sintering includes the following steps:

[0018] Heating stage: The temperature is raised to the insulation temperature, and the pressure is first increased to the maximum pressure, and then reduced to the insulation pressure; the maximum pressure is 44MPa~46MPa;

[0019] Insulation stage: The temperature is controlled at the insulation temperature and the pressure is controlled at the insulation pressure to carry out insulation treatment;

[0020] Cooling stage: After the temperature is reduced from the holding temperature to the cooling temperature, the sample is taken out. The cooling temperature is 0℃~2℃.

[0021] Thirdly, this application provides a high-voltage switchgear, comprising the high-voltage switch contact as described in any one of the above-mentioned methods, or a high-voltage switchgear prepared by the method described in any one of the above-mentioned methods.

[0022] The aforementioned high-voltage switch contact achieves a good balance of conductivity, wear resistance, and thermal conductivity, and can be manufactured using a relatively simple process. In other words, the high-voltage switch contact of this application exhibits excellent performance and a simple manufacturing process. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the high-voltage switch contacts prepared in Examples 1 to 3 of this application, wherein, from left to right, they are samples from Example 1, Example 2, and Example 3;

[0024] Figure 2 This is a comparative schematic diagram showing the conductivity of the high-voltage switch contacts prepared in Examples 1 to 3 of this application;

[0025] Figure 3 This is a comparative schematic diagram of the Vickers hardness of the high-voltage switch contacts prepared in Examples 1 to 3 of this application;

[0026] Figure 4 This is a comparative schematic diagram showing the friction coefficients of the high-voltage switch contacts prepared in Examples 1 to 3 of this application;

[0027] Figure 5 This is a comparative schematic diagram showing the thermal conductivity of the high-voltage switch contacts prepared in Examples 1 to 3 of this application. Detailed Implementation

[0028] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, a detailed description of specific embodiments of this application is provided below. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0030] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0032] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0033] One embodiment of this application provides a high-voltage switch contact, including a copper substrate; a protective coating is disposed on the surface of the copper substrate; the material of the protective coating includes a silver-copper oxide composite material.

[0034] The aforementioned high-voltage switch contact achieves a good balance of conductivity, wear resistance, and thermal conductivity, and can be manufactured using a relatively simple process. In other words, the high-voltage switch contact of this application exhibits excellent performance and a simple manufacturing process.

[0035] In some embodiments, the protective coating is a silver-copper oxide composite coating.

[0036] In some embodiments, the protective coating completely covers the copper substrate.

[0037] In some embodiments, the mass of copper oxide in the protective coating accounts for 3% to 8% of the mass of the protective coating.

[0038] Understandably, with increasing CuO content, the microstructure of the CuO phase in the silver matrix changes from an isolated island structure to a semi-continuous, continuous framework structure. Furthermore, the density, electrical conductivity, Vickers hardness, coefficient of friction, and thermal conductivity of the protective coating all change accordingly with variations in the mass of copper oxide. Within the aforementioned range of percentages of copper oxide mass in the protective coating, it is convenient to achieve excellent performance for high-voltage switch contacts.

[0039] Optionally, the percentage of copper oxide in the protective coating is 3%, 4%, 5%, 6%, 7% or 8%, or the percentage of copper oxide in the protective coating may be within any two of the above percentages.

[0040] In some embodiments, the copper oxide phase in the protective coating is uniformly distributed in a semi-continuous framework within the silver matrix.

[0041] It is understandable that "semi-continuous skeleton uniform distribution" in composite materials refers to a typical distribution state of the reinforcing phase or filler phase in the matrix phase, and is also an ideal structural morphology in composite materials. In this application, copper oxide is the reinforcing phase and silver is the matrix phase. Specifically: in the protective coating, the copper oxide phases overlap and connect to form a three-dimensional continuous network skeleton matrix, but the gaps in this skeleton are completely filled by the silver matrix phase; and the entire three-dimensional network skeleton is macroscopically free of agglomeration, pores, and segregation. When sampling any micro-region of the composite material, the proportions of the two phases, the porosity of the skeleton, and the overlap density are basically consistent, that is, the continuity of the skeleton is semi-continuous, and the spatial distribution is uniform. It should be noted that the semi-continuous description in this application is not the same as discontinuous, but a specific definition for composite materials, different from completely continuous and discrete distributions, and is an intermediate state among the three.

[0042] In some embodiments, the mass of copper oxide in the protective coating accounts for 5% of the mass of the protective coating.

[0043] In the above embodiments, the mass percentage of copper oxide in the protective coating is 5%, which facilitates the formation of a semi-continuous skeleton of copper oxide in the protective coating, thereby obtaining a high-voltage switch contact with better overall performance.

[0044] Another embodiment of this application provides a method for preparing a high-voltage switch contact, comprising the following steps:

[0045] Provide copper substrate;

[0046] A mixed raw material is obtained by mixing silver raw material and copper oxide raw material. A protective coating is prepared by sintering the mixed raw material onto the surface of a copper substrate by spark plasma. The material of the protective coating includes silver-copper oxide composite material.

[0047] Understandably, spark plasma sintering (SPS, also known as plasma-activated sintering or plasma-assisted sintering) is a novel pressure sintering technology, belonging to the category of rapid sintering processes. Its core principle is that a DC pulsed current is directly passed through the mold and the sintering powder, simultaneously applying axial pressure. Utilizing Joule heating and the plasma activation effect, the powder achieves rapid densification and sintering, representing a cutting-edge technology in powder metallurgy. Unlike traditional sintering, which involves external heating and pressurization, with heat transferred from outside the mold to the powder, spark plasma sintering utilizes internal self-heating and pressurization. The current directly passes through the sample or mold to generate heat, significantly improving heating efficiency and uniformity.

[0048] Spark plasma sintering has the following advantages:

[0049] The rapid heating rate and short sintering time of spark plasma sintering (SPSS) allow for lower sintering temperatures compared to traditional sintering. Because plasma activates the particle surface, it lowers the activation energy for sintering, enabling densification without high temperatures and effectively suppressing grain growth. Simultaneously, the relative density of the final sintered body can reach 95%–99.9%, with extremely low porosity, resulting in significantly improved mechanical and physicochemical properties. Furthermore, the rapid heating, low-temperature sintering, and short holding time suppress abnormal grain growth, leading to ultrafine grains. These ultrafine grains and high density result in sintered bodies with superior hardness, strength, toughness, electrical conductivity, and thermal conductivity compared to samples obtained through traditional sintering processes; they also reduce component segregation and improve microstructure uniformity. Protective coatings prepared by SPSS achieve a balance of good electrical conductivity, wear resistance, and thermal conductivity.

[0050] In some embodiments, mixing silver raw material and copper oxide raw material to obtain a mixed raw material includes the following steps:

[0051] The silver and copper raw materials were cleaned sequentially using alkaline and acidic solutions.

[0052] The cleaned silver and copper raw materials were ball-milled and mixed.

[0053] It is understandable that cleaning silver and copper raw materials with alkaline and acid solutions in sequence means cleaning silver raw materials with alkaline and acid solutions respectively, and cleaning copper raw materials with alkaline and acid solutions respectively.

[0054] In some embodiments, the silver material is silver powder.

[0055] In some embodiments, the copper raw material is copper powder.

[0056] In some embodiments, the copper powder has a particle size of 3 μm to 5 μm.

[0057] Optionally, the particle size of the copper powder is 3μm, 3.2μm, 3.5μm, 3.8μm, 4μm, 4.2μm, 4.5μm, 4.8μm or 5μm, or the particle size of the copper powder may be within the range of any two of the above particle sizes.

[0058] In some embodiments, the alkaline solution includes a NaOH solution.

[0059] In some embodiments, the concentration of the NaOH solution is 50 g / L to 70 g / L.

[0060] Optionally, the concentration of the NaOH solution is 50 g / L, 52 g / L, 55 g / L, 58 g / L, 60 g / L, 62 g / L, 65 g / L, 68 g / L, or 70 g / L, or the concentration of the NaOH solution may be within any two of the above concentrations.

[0061] In some embodiments, the acid solution includes an HNO3 solution.

[0062] In some embodiments, the concentration of the HNO3 solution is 180 g / L to 220 g / L.

[0063] Optionally, the concentration of the HNO3 solution is 180 g / L, 190 g / L, 200 g / L, 210 g / L or 220 g / L, or the concentration of the HNO3 solution may be within any two of the above concentrations.

[0064] In some embodiments, during the ball milling process, the ball-to-material ratio is set to 10:1, and the ratio of large, medium, and small balls is 5:3:1.

[0065] In some embodiments, the ball mill rotates at a speed of 600 r / min to 800 r / min.

[0066] Optionally, the rotational speed of the ball mill is 600 r / min, 620 r / min, 650 r / min, 680 r / min, 700 r / min, 720 r / min, 750 r / min, 780 r / min or 800 r / min, or the rotational speed of the ball mill can be within the range of any two of the above rotational speeds.

[0067] In some embodiments, the ball milling time is 15 min to 25 min.

[0068] Optionally, the ball milling time is 15 min, 17 min, 19 min, 21 min, 23 min or 25 min, or the ball milling time can be within any two of the above times.

[0069] In some embodiments, the holding temperature of the spark plasma sintering is 920℃~940℃, the holding time of the spark plasma sintering is 25min~35min, and the holding pressure of the spark plasma sintering is 19MPa~21MPa.

[0070] Optionally, the holding temperature for spark plasma sintering is 920℃, 922℃, 925℃, 928℃, 930℃, 932℃, 935℃, 938℃ or 940℃, or the holding temperature for spark plasma sintering can be within the range of any two of the above temperatures.

[0071] Optionally, the holding time for spark plasma sintering is 25 min, 27 min, 29 min, 31 min, 33 min, or 35 min, or the holding time for spark plasma sintering can be within any two of the above-mentioned times.

[0072] Optionally, the holding pressure for spark plasma sintering is 19 MPa, 19.2 MPa, 19.5 MPa, 19.8 MPa, 20 MPa, 20.2 MPa, 20.5 MPa, 20.8 MPa or 21 MPa, or the holding pressure for spark plasma sintering can be within any two of the above pressures.

[0073] In some embodiments, the preparation of a protective coating on the surface of a copper substrate by spark plasma sintering using a mixed raw material includes the following steps:

[0074] Heating phase: The temperature is raised to the holding temperature, and the pressure is first increased to the maximum pressure, and then reduced to the holding pressure; the maximum pressure is 44MPa~46MPa;

[0075] Insulation stage: The temperature is controlled at the insulation temperature and the pressure is controlled at the insulation pressure to carry out insulation treatment;

[0076] Cooling stage: After the temperature is reduced from the holding temperature to the cooling temperature, the sample is taken out. The cooling temperature is 0℃~2℃.

[0077] Optionally, the maximum pressure is 44 MPa, 44.2 MPa, 44.5 MPa, 44.8 MPa, 45 MPa, 45.2 MPa, 45.5 MPa, 45.8 MPa or 46 MPa, or the maximum pressure may be within the range of any two of the above pressures.

[0078] Optionally, the cooling temperature is 0℃, 0.2℃, 0.5℃, 0.8℃, 1℃, 1.2℃, 1.5℃, 1.8℃ or 2℃, or the cooling temperature may be within the range of any two of the above temperatures.

[0079] In some embodiments, the heating time during the heating phase is 35 min to 40 min.

[0080] Optionally, the heating time of the heating stage is 35 min, 36 min, 37 min, 38 min, 39 min or 40 min, or the heating time of the heating stage can be within any two of the above times.

[0081] Another embodiment of this application provides a high-voltage switchgear, including a high-voltage switch contact of any one of the above claims, or a high-voltage switchgear prepared by any one of the above claims' high-voltage switch contact preparation methods.

[0082] For example, high-voltage switchgear can be a circuit breaker, disconnector, load switch or grounding switch.

[0083] The following are specific examples:

[0084] Example 1

[0085] Method for manufacturing high-voltage switch contacts:

[0086] (1) Copper oxide powder with a particle size of 4μm was selected as copper oxide raw material and silver powder was selected as silver raw material. In this embodiment, the mass of the silver-copper oxide composite coating is 10g and the mass percentage of copper oxide is 3%, which is 0.3g.

[0087] (2) To remove oil stains from the surface of the materials, copper oxide powder and silver powder were subjected to alkaline washing and acid washing. The alkaline washing used a 60 g / L NaOH solution, and the acid washing used a 200 g / L HNO3 solution. Subsequently, the copper oxide powder and silver powder were thoroughly mixed using a high-energy ball mill. During the ball milling process, the ball-to-material ratio was set to 10:1, and the ratio of large, medium and small balls was 5:3:1. The milling was carried out at a speed of 700 r / min for 20 min.

[0088] (3) The sample is subjected to SPS treatment; during the heating stage, the temperature is raised to 930℃, the pressure is increased to 45MPa, and then reduced to 20MPa. The heating stage takes a total of 37 minutes. When the temperature reaches 930℃, the temperature and pressure inside the furnace are kept constant. After holding the temperature for 30 minutes, the cooling stage can be entered. When the temperature inside the furnace drops to 0℃, the cooled sample is taken out and then ground and polished.

[0089] Example 2

[0090] The preparation method of the high-voltage switch contact in Example 2 is basically the same as that in Example 1, except that the mass percentage of copper oxide in Example 2 is 5%.

[0091] Example 3

[0092] The preparation method of the high-voltage switch contact in Example 3 is basically the same as that in Example 1, except that the mass percentage of copper oxide in Example 3 is 8%.

[0093] Reference Figure 1 As shown, Figure 1 This is a schematic diagram of the high-voltage switch contacts prepared in Examples 1 to 3. Performance tests and characterization were performed on the high-voltage switch contacts prepared in Examples 1 to 3.

[0094] Performance testing and characterization methods:

[0095] 1. Microscopic tissue structure analysis:

[0096] The microstructure of the material was observed using a scanning electron microscope. In order to ensure that the elemental distribution of the sintered silver-copper oxide composite material coating is uniform and has excellent surface morphology, the microstructure of the silver-copper oxide composite material coating sample was observed using a JSM-7000F cold field emission SEM and the phase composition was analyzed by energy dispersive spectroscopy (EDS).

[0097] 2. Friction and wear properties:

[0098] High-voltage switchgear vibrates during operation, and the switch contacts, as the main connecting elements, frequently rub against the conductors. Therefore, wear resistance is one of the important performance indicators of contact coating materials, and the wear resistance of the coating directly determines the service life of the contact fingers. In this application, a 339-GSRⅡ type steel wool abrasion tester was used to conduct friction tests on the silver-copper oxide composite coating. This equipment uses a ball-and-disc friction test, with the friction ball made of 6063 aluminum alloy. A 25g load was selected for 20 minutes of friction, and the wear resistance was evaluated by analyzing the coefficient of friction and the size of the wear marks.

[0099] 3. Electrical conductivity:

[0100] As a crucial connecting element, the coating material of switch contacts must possess excellent conductivity, as the conductivity of the coating directly determines its electrical performance. This invention employs a D60K digital metal conductivity meter to measure the conductivity of a silver-copper oxide composite coating. To avoid errors, the instrument must be calibrated before testing, and the conductivity of the material is directly measured using a metal probe.

[0101] 4. Vickers hardness:

[0102] Hardness measures a metallic material's ability to resist indentation by a hard object. Switch contacts are continuously subjected to inward compressive force, and their deformation directly affects the stable transmission of electrical energy. Therefore, the coating material must possess excellent hardness. In this application, the Vickers hardness of the composite coating was tested using an HVS-1000Z Vickers hardness tester, following the method described in standard GB / T7997—2014.

[0103] 5. Thermal conductivity:

[0104] Thermal conductivity reflects a material's ability to conduct heat. Switch contact coatings need to possess good thermal conductivity to prevent increased contact resistance due to corrosion and poor contact during operation, which could lead to localized overheating and burn-out of the electrical contact material or the contacts themselves. This application uses an LFA 447 thermal conductivity meter to measure the thermal conductivity of the silver-copper oxide composite coating. To ensure accuracy, a layer of graphite is sprayed onto the sample surface before testing to improve precision.

[0105] 6. Density:

[0106] The density of the silver-copper oxide composite coating is closely related to its physical and mechanical properties. Materials with higher density generally have higher hardness, strength, rigidity, and better wear resistance. In this application, the density of the material was tested using an ET-320 electronic densitometer.

[0107] By conducting microstructure analysis, density testing, electrical conductivity testing, Vickers hardness testing, wear resistance testing, and thermal conductivity testing on three silver oxide copper coatings with different contents, the following main conclusions can be drawn:

[0108] 1. In silver-copper oxide composite coatings, with the increase of copper oxide content, the microstructure of the copper oxide phase in the silver matrix changes from an isolated island structure to a semi-continuous, continuous skeletal structure. In Example 2, the copper oxide phase is uniformly distributed in the silver matrix as a semi-continuous skeletal structure, exhibiting good strength, hardness, and wear resistance.

[0109] 2. The density of the silver-copper oxide composite coating first decreases and then increases with the increase of copper oxide mass fraction, and the silver-copper oxide composite coating sample with copper oxide mass fraction of 3% has the highest density.

[0110] 3. Reference Figure 2 As shown, the sample exhibits the highest conductivity and best electrical conductivity when the copper oxide mass fraction is 3%, while the sample exhibits the lowest conductivity, approximately 43.5 Ms / m, when the copper oxide mass fraction is 8%.

[0111] 4. Reference Figure 3As shown, the sample with a copper oxide mass fraction of 8% has the highest Vickers hardness, while the Vickers hardness values ​​of samples with copper oxide mass fractions of 3% and 5% increase with the increase of copper oxide content.

[0112] 5. Reference Figure 4 As shown, the sample with a copper oxide mass fraction of 8% has the highest coefficient of friction and relatively poor wear resistance. The samples with a copper oxide mass fraction of 3% and 5% have similar coefficients of friction and excellent wear resistance. The sample with a copper oxide mass fraction of 5% can reduce silver consumption and lower costs while ensuring excellent wear resistance and a low coefficient of friction.

[0113] 6. Reference Figure 5 As shown, the thermal conductivity of the samples decreases with increasing copper oxide mass fraction. The sample with 8% copper oxide mass fraction has the best thermal conductivity, while the sample with 3% copper oxide mass fraction has the worst thermal conductivity.

[0114] Based on the above test and analysis results, it can be concluded that among the silver-copper oxide composite coatings with copper oxide contents of 3%, 5%, and 8%, the sample with a copper oxide content of 5% exhibits the best overall performance.

[0115] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0116] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims, and the specification and drawings can be used to interpret the content of the claims.

Claims

1. A high-voltage switch contact, characterized in that, It includes a copper substrate; a protective coating is disposed on the surface of the copper substrate; the material of the protective coating includes a silver-copper oxide composite material.

2. The high-voltage switch contact according to claim 1, characterized in that, The protective coating is a silver-copper oxide composite material coating.

3. The high-voltage switch contact according to claim 2, characterized in that, In the protective coating, the mass percentage of copper oxide is 3% to 8% of the total mass of the protective coating.

4. The high-voltage switch contact according to claim 3, characterized in that, In the protective coating, the copper oxide phase is uniformly distributed in the silver matrix in a semi-continuous framework.

5. The high-voltage switch contact according to claim 3, characterized in that, In the protective coating, the mass percentage of copper oxide is 5% of the mass of the protective coating.

6. A method for manufacturing a high-voltage switch contact, characterized in that, Includes the following steps: Provide copper substrate; A mixed raw material is obtained by mixing silver raw material and copper oxide raw material. A protective coating is prepared by using the mixed raw material to sinter it onto the surface of the copper substrate by spark plasma sintering. The material of the protective coating includes a silver-copper oxide composite material.

7. The method for preparing a high-voltage switch contact according to claim 6, characterized in that, The process of mixing silver raw material and copper oxide raw material to obtain a mixed raw material includes the following steps: The silver raw material and the copper raw material were cleaned sequentially using alkaline solution and acid solution; The cleaned silver and copper raw materials are ball-milled and mixed.

8. The method for preparing a high-voltage switch contact according to any one of claims 6 to 7, characterized in that, The holding temperature of the discharge plasma sintering is 920℃~940℃, the holding time of the discharge plasma sintering is 25min~35min, and the holding pressure of the discharge plasma sintering is 19MPa~21MPa.

9. The method for preparing a high-voltage switch contact according to claim 8, characterized in that, The preparation of a protective coating on the surface of the copper substrate using the mixed raw materials by spark plasma sintering includes the following steps: Heating stage: The temperature is raised to the insulation temperature, and the pressure is first increased to the maximum pressure, and then reduced to the insulation pressure; the maximum pressure is 44MPa~46MPa; Insulation stage: The temperature is controlled at the insulation temperature and the pressure is controlled at the insulation pressure to carry out insulation treatment; Cooling stage: After the temperature is reduced from the holding temperature to the cooling temperature, the sample is taken out. The cooling temperature is 0℃~2℃.

10. A high-voltage switchgear, characterized in that, The high-voltage switchgear includes the high-voltage switch contact as described in any one of claims 1 to 5, or the high-voltage switch contact as described in any one of claims 6 to 9, and the high-voltage switchgear prepared by the same method.

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