45 results about "Arc erosion" patented technology

The invention discloses high-voltage wiring harness connector terminal fretting wear test equipment which comprises an equipment base, a high-frequency vibration exciter and a lifting platform are mounted on the equipment base, and a mounting platform is arranged at the top of the lifting platform; a left test piece mounting loading mechanism and a right test piece mounting force measuring device are arranged on the mounting platform. The device can realize a multi-physics field coupling test, current-carrying friction and arc erosion of an electric contact surface in a real working condition are simulated by combining a current load with high-frequency mechanical wear, and the electric-mechanical coupling wear characteristic of a new energy automobile charging terminal is accurately reproduced. The device supports the dynamic adjustment of normal load, simulates the contact pressure change of the left and right test samples of the test terminal in the plugging process through the test sample pin and the test sample jack, can be used for researching the relevance between the fretting wear and the contact resistance of the test terminal under different loads, and realizes the test of the terminal under complex working conditions in a laboratory environment. The test process is convenient, efficient and accurate, and the test cost and the test period are greatly reduced.

The invention relates to the technical field of high-voltage electric power, and particularly discloses a high-voltage electric mechanical part wear state evaluation method and system.The method comprises the steps that multi-sensor time sequence signals, operation overshoot mechanical kinetic energy and contact surface temperature are collected, a normalized wear signal sequence is obtained through kinetic energy compensation, and multi-dimensional features are extracted; a comprehensive feature vector is generated through lightweight attention mechanism fusion, a thermal coupling factor correction wear mode is calculated based on temperature, a real-time state and lubrication dielectric characteristics are fused to obtain an evaluation aggressive coefficient, levels are mapped, and the arc erosion cumulant after environment correction is combined to obtain a high-precision arc erosion model. And generating an evaluation report of the content index, the composite fault and the residual life. According to the method, accurate decoupling of a concurrent wear mode and self-adaption of an evaluation strategy working condition can be realized, evaluation precision and embedded deployment requirements are considered, the problems of rough evaluation, neglect of multi-factor coupling and poor adaptability in the prior art are effectively solved, and reliable support is provided for predictive maintenance of high-voltage electric mechanical parts.

This invention provides a weldable, lightweight, long-life arc-initiating electrode and welding method, including an anode head, a cathode head, an anode column, and a cathode column. The anode head and cathode head are made of single or composite metal conductor materials resistant to arc erosion; the anode column and cathode column are also made of single or composite metal conductor materials. The current path is as follows: the arc igniter is connected to both ends of the track in the muzzle region of a high-speed electromagnetic propulsion device, powered by an external power source. Current flows through the track and armature path of the high-speed electromagnetic propulsion device. The armature, under electromagnetic force, accelerates and slides from the muzzle towards the muzzle. When the armature exits the muzzle, it disengages from the track. Simultaneously, the metal or plasma medium in the gap between the bypass electrodes of the arc igniter induces gap breakdown discharge, achieving arc initiation. This invention meets requirements for conductivity and high tensile strength.

The invention discloses a copper-chromium contact surface laser remelting rotating device. The copper-chromium contact surface laser remelting rotating device comprises a working table, a rotating clamping table, an adjusting assembly and a laser, wherein the rotating clamping table and the adjusting assembly are arranged on the working table; the rotary clamping table comprises a mounting seat, a rotary seat rotationally clamped on the mounting seat, a movable clamping block arranged on the rotary seat and a rotary motor for providing power for the rotary seat; the adjusting assembly comprises a first arc-shaped frame and an adjusting seat; the laser is arranged on the lower bottom surface of the adjusting seat; the device is reasonable in structural design, the laser is arranged on the adjusting seat capable of freely moving along the first arc-shaped frame, so that the laser can be matched with the curved surface radian of the R chamfer of the copper-based contact, it is ensured that a laser beam can'follow 'each point of the chamfer surface, the machining blind area of the curved surface radian in the circumferential direction is completely eliminated, and the machining efficiency is improved. The microstructure of a copper-chromium alloy remelting layer is refined, alloy elements are distributed more evenly, and the hardness, abrasion resistance, arc erosion resistance and other performance of the surface of the copper-chromium contact are remarkably improved.

An operating mechanism for a transfer switch, the operating mechanism comprising a bracket and an energy storage mechanism for driving a main shaft. The energy storage mechanism comprises a first energy storage mechanism, a second energy storage mechanism, and a turnover member. When the turnover member rotates, a corresponding connecting rod shaft is driven by means of one of side walls at two ends of a first arc-shaped sliding groove or a second arc-shaped sliding groove to drive a connecting rod mechanism of the first energy storage mechanism or the second energy storage mechanism to move, such that a corresponding energy storage spring first stores energy and releases the energy after passing a balance position so as to drive the connecting rod mechanism to drive the main shaft to rotate, and the connecting rod shaft slides to the other ends of the first arc-shaped sliding groove and the second arc-shaped sliding groove. In this way, during the energy storage process of the energy storage mechanisms, the main shaft does not move, and after the energy storage mechanisms release the energy, the main shaft is driven to quickly rotate and switch a power supply. The switching speed of an automatic transfer switch is independent of the speed of a manual operation mechanism and an automatic operation mechanism, and the automatic transfer switch can reduce arc erosion on a switch contact system.

This invention discloses a method for preparing a stationary contact, comprising: melting pure copper at high temperature and casting it into a mold to form a ring-shaped blank, wherein the blank has multiple mounting holes spaced apart circumferentially; grinding the inner surface of the blank using a grinding mechanism; cleaning the inner surface of the blank; forming a conductive layer on the inner surface of the blank, wherein the conductive layer is made of copper-tungsten alloy material and formed by high-temperature sintering using powder metallurgy technology; and grinding the mounting holes and the end face of the blank. The stationary contact obtained by the above method has improved strength, is resistant to arc erosion, and has an extended service life.

This application discloses a method for preparing silver-tin oxide electrical contact material for magnetic latching relays, comprising the following steps: depositing indium oxide and tin oxide sequentially on the surface of silver powder by physical vapor deposition to obtain a coated powder, wherein the indium oxide content is 0.3~0.8wt%, the tin oxide content is 8~10wt%, and the balance is silver; mixing the coated powder, yttrium-stabilized tetragonal zirconium oxide, and trace additives to obtain a composite powder, wherein the trace additives are copper oxide or tungsten oxide, and the mass ratio of yttrium-stabilized tetragonal zirconium oxide to coated powder is (2~5):100; hot pressing the composite powder at 25~35MPa to obtain a blank, and holding it at that temperature for 1~2h; hot extrusion processing to process the blank into a rod; multi-pass drawing to produce a wire, and performing intermediate annealing treatment during the drawing process, with each annealing time being 1~2h. The electrical contact prepared by this method has high contact resistance stability and arc erosion resistance.

The invention belongs to the technical field of composite material preparation, and particularly relates to a tungsten infiltrated copper composite material and a preparation method thereof. According to the invention, through a multi-scale through pore network formed by'prefabricated material construction ', molten copper liquid can be rapidly filled along a large pore channel and fully permeates into the tail end of a small pore, so that the defect of'black core' generated by closed pores is thoroughly avoided. According to the prepared composite material, the tungsten phase and the copper phase respectively form a stable and communicated three-dimensional network, so that the unification of high conductivity (greater than or equal to 60% IACS), high strength and toughness (hardness greater than or equal to 100 HB) and excellent arc ablation resistance is fundamentally and synergistically realized, and the long-standing limitation of'impossible performance triangle 'is effectively broken through. And the process is high in integration level, green and remarkable in strengthening effect, and process simplification, environmental protection strengthening and performance improvement are achieved at one stroke. The advantages of raw materials and process cost are outstanding, the industrialization prospect is wide, and the relationship among high performance, designability and mass productivity is perfectly balanced.

The invention discloses a conductive reinforced phase material and an in-situ preparation method thereof, and belongs to the technical field of core electric contact materials for switches. The reinforced phase material is Ti3AlC2-coated Al2O3 and is composed of an inner layer and an outer layer in the coaxial direction, the inner layer is of a hollow cylindrical structure, the component of the inner layer is Ti3AlC2, and the outer layer is an Al2O3 coating layer generated on the surface of the inner layer in situ. The in-situ preparation method comprises the following steps: by taking a carbon nanotube as a template and eutectic molten salt as a carrier, preparing the conductive reinforced phase material with the double-layer concentric cylindrical composite structure through vacuum freeze drying, molten salt shielding reaction and high-temperature and high-pressure oxidation treatment. Compared with an original MAX-phase powder reinforced metal-based electric contact composite material and a commercial metal-based electric contact composite material, the novel material is compounded with conductive metal powder such as silver and copper, the electric conduction and heat conduction performance and the arc erosion resistance of the electric contact composite material can be remarkably enhanced, and the potential of replacing a traditional electric contact material is huge.

The invention discloses a magnetic blow-out arc extinguishing structure of a GIS circuit breaker. The magnetic blow-out arc extinguishing structure comprises an arc moving contact, a magnetic blow-out coil, an arc static contact, a main moving contact and a main static contact, the main contact group and the arc contact group are respectively connected with corresponding electrodes, and current is conducted only through the main contact group during normal through-flow; the magnetic blow-out coil is poured in an insulating mode through epoxy resin and independently arranged on the outer side of the arc contact, a safe distance is kept between the magnetic blow-out coil and the arc contact to avoid arc ablation, and meanwhile the magnetic blow-out strength is regulated and controlled through an external pre-charging capacitor. When a short-circuit fault occurs, the main contact is firstly separated to transfer current to the arc contact group, after the arc contact is separated to generate an electric arc, the pre-charging capacitor discharges to the magnetic blow-out coil to generate pulse strong magnetism, the electric arc is driven to directionally extend and intensified convective heat exchange with SF6 gas, and rapid arc extinguishing is realized by combining the synergistic effect of gas blow-out and magnetic blow-out. The device is suitable for GIS systems with different voltage levels of 110 kV to 550 kV, the arc extinguishing response speed is high, the magnetic blow-out strength is adjustable, and the short-circuit fault breaking reliability of a high-voltage system is remarkably improved.

This invention discloses a main shield, its preparation method, and its application in a vacuum interrupter and circuit breaker, belonging to the technical field of vacuum switchgear. The main shield includes an inner surface, an outer surface, and an end-curled edge region extending inward from the outer surface. At least a portion of its surface is provided with an insulating ceramic functional layer. The insulating ceramic functional layer forms a spatially continuously varying structural system along the inner surface to the end-curled edge region and extending to the outer surface, giving different regions different structural characteristics. Specifically, the inner surface away from the curled edge region has a multi-layered structure, the inner surface near the curled edge region has a gradient structure with continuously varying porosity, density, and thickness, and the end-curled edge region and outer surface region have a dense and uniform structure. This invention also provides a vacuum interrupter and circuit breaker including the above-mentioned main shield. The main shield, vacuum interrupter, and circuit breaker of this invention can simultaneously meet the requirements of arc erosion resistance, stress relief, and electric field control, improving insulation reliability and operational stability.

The invention relates to the technical field of electric contact materials, in particular to a silver tungsten carbide electric contact material for a high-breaking circuit breaker and a preparation method, and the silver tungsten carbide electric contact material for the high-breaking circuit breaker comprises the following raw materials in percentage by weight: less than or equal to 70% of graphene-loaded tungsten carbide powder, 2-3.5% of an additive and the balance of silver; the additive is a mixture of titanium carbide, lanthanum oxide and silicon powder; the electric arc erosion rate of the silver tungsten carbide electrical contact material is reduced.

This invention discloses a non-disassembly repair method for 10kV vacuum circuit breakers based on nanoscale electrical conduction optimization protection in the field of high-voltage electrical equipment inspection and maintenance technology. The method includes cleaning the vacuum bubble shell, preparing a carboxylic acid aluminum oxane silsesquioxane block copolymer dispersion, spraying the dispersion into the arc-extinguishing chamber via aerosol spraying, and then applying a pulsed DC electric field to induce the directional deposition of nanoparticles after settling. Subsequently, gradient vacuum-driven anchoring and solvent removal are performed, using infrared heating combined with gradient vacuum extraction to remove the solvent. Next, the contacts are closed and AC current is applied for low-temperature sintering bonding to form a quantum tunnel conductive layer. Finally, gradient aging treatment and comprehensive performance verification are performed. This invention can effectively repair arc erosion defects, reduce contact resistance, improve insulation performance and vacuum level, and achieve high-performance recovery of circuit breakers; the process is feasible.

The application discloses a high-entropy alloy particle reinforced copper-based contact material and a preparation method and application thereof, and belongs to the technical field of contact materials. The application adds a reinforcing phase high-entropy particle into a copper base to improve the anti-ablation performance of the contact material. The application mixes powders of five different elements, ball-mills, anneals, and obtains high-entropy alloy powder, then mixes copper powder and the high-entropy alloy powder, ball-mills, and obtains Cu-HEAs composite powder, and finally adopts SPS hot-pressing sintering technology to obtain the high-entropy alloy reinforced copper-based contact material. The Cu-HEAs contact material has excellent physical and mechanical properties, enhances the anti-arc erosion performance of the copper-based contact material, and prolongs the service life of the contact.

The invention discloses a method for relieving arc ablation of a carbon slide plate by using natural airflow and a pantograph, and relates to the technical field of pantographs, and the method comprises the following steps: forming a vertical through slot in the carbon slide plate, and arranging an airflow guide device on the windward side of a pantograph head plate. The pantograph comprises a pantograph lifting device, a pantograph head plate, an airflow guide device and a carbon slide plate. The airflow guiding device is composed of a windward hole and a redirection hole. The redirection hole is designed to be a long-strip-shaped hole matched with a carbon sliding plate groove in shape, the windward hole is formed by a plurality of small holes, and the pneumatic function and the structural strength are both considered. A flow control device is introduced, a rotating shaft and flow control blades are matched with a torsion spring to achieve self-adaptive adjustment, high-speed airflow is prevented from blowing out an electric arc, it is ensured that the system dynamically maintains the controllable weakening state of the electric arc at different running speeds, the electric arc is effectively restrained, and the pantograph-catenary current collection continuity is guaranteed. No extra energy is needed, the structure is simple and reliable, and the service life of the carbon slide plate is remarkably prolonged.

The application belongs to the technical field of electric contact material preparation, and particularly relates to a silver-based graphene layered composite electric contact material, a preparation method and application thereof, a layered composite structure of the layered composite electric contact material "nickel transition layer-copper adhesive layer-silver / graphene composite layer", and a preparation method and application thereof. The composite electric contact material has a synergistic optimization of comprehensive performance, and simultaneously solves the contradiction that the conductive performance, mechanical performance and arc erosion resistance of a traditional silver plating layer are difficult to be considered at the same time, and has wide applicability in the fields of electronic devices and rail transit.

The application discloses a preparation method of a silver tin oxide electric contact material with good plasticity and arc erosion resistance, and comprises the following steps: first, taking Ag ingot, Sn ingot and X ingot of an additive element to prepare Ag-Sn alloy powder with a required particle size; the obtained powder is oxidized to obtain AgSnO2 mother powder; then, the required amounts of Ag, Sn and X elements are calculated according to the component proportion of the required preparation material, and are weighed for standby, wherein the Sn and X elements are weighed in the form of AgSnO2 mother powder, and the Ag element is weighed in the form of silver nitrate and AgSnO2 mother powder; then, an alkaline substance in excess of silver nitrate is weighed, and the alkaline substance and the silver nitrate are respectively prepared into solutions; then, the weighed AgSnO2 mother powder is added into the alkaline solution, and the silver nitrate solution is continuously added for reaction to obtain AgSnO2 powder; and finally, the obtained powder is prepared into a silver tin oxide electric contact through a conventional process. The contact prepared by adopting the method has good plasticity and arc erosion resistance.

The invention relates to the technical field of electrical contact materials, in particular to a SnO2 electrical contact material for a new energy electrical appliance and a preparation method of the SnO2 electrical contact material. The SnO2 electrical contact material comprises 8-15% of tin oxide, 0.5-3% of a composite additive, 0.1-2% of an accelerant and the balance of silver. According to the invention, yttrium ions and chromium ions can be partially dissolved in tin oxide crystal lattices, so that the thermal decomposition reaction of tin oxide at extremely high arc temperature is effectively inhibited, the material loss caused by tin element volatilization is reduced, the second additive generates a high-melting-point composite oxide phase after high-temperature calcination, and the high-melting-point composite oxide phase is uniformly distributed in a silver matrix; as a physical skeleton for resisting arc erosion, the accelerant mainly plays a role in dispersing and interface optimizing, and an interface compound containing zinc, lanthanum, boron and oxygen is formed after the accelerant is calcined, so that the wettability and binding force between tin oxide particles and a silver matrix are improved, uniform distribution of the tin oxide particles is ensured, local overheating and concentrated erosion are avoided, and the service life of the tin oxide particles is prolonged. Therefore, the mass loss of arc ablation is obviously reduced.

This application provides a copper-steel composite element for miniature circuit breakers, an electrical contact assembly, and a miniature circuit breaker. The copper-steel composite element includes: a magnetic conductor, one end of which has at least one through groove extending through the thickness direction of the magnetic conductor; and an arc-starting angle, one end of which has a fitting portion matching the shape of the through groove, the fitting portion being riveted and fitted into the through groove. This application connects the end of the arc-starting angle to the through groove of the magnetic conductor by riveting and fitting together, forming a laterally composite copper-steel composite element. This allows for the connection between the arc-starting angle and the magnetic conductor without relying on additional parts, enabling rapid arc extinguishing without reducing the conductivity of the arc-starting electrical contact assembly. This makes the electrical contacts of the miniature circuit breaker more resistant to arc erosion, thus extending the product's service life.

This invention provides a copper-based laser cladding powder and a method for preparing a copper-based alloy cladding layer on the surface of a disconnector switch contact, belonging to the field of electrical contact material technology. The copper-based laser cladding powder of this invention comprises: 6-15% Mo-Cr-Ni alloy powder; and 85-94% Cu-Ag alloy powder. The copper-based laser cladding powder provided by this invention possesses wear resistance, high conductivity, and corrosion resistance, making it suitable for laser cladding processes. It effectively avoids the problem of material failure on the surface of disconnector switch contacts. Cu's excellent electrical and thermal conductivity makes it a key component of the electrical contact material; the addition of Ag improves the conductivity of the alloy material; the addition of Mo enhances the material's wear resistance and arc erosion resistance; Ni and Cr not only improve cladding layer defects but also strengthen the overall mechanical properties of the cladding layer, improve the alloy's corrosion resistance, and extend the service life of the electrical contacts.

The invention discloses a high-carbon-content and high-strength silver graphite electric contact material and a preparation method thereof. The electric contact material comprises a three-dimensional continuous silver network formed by foamed silver and a functional phase filled in pores of the silver network, the three-dimensional isotropic foam silver network is used for replacing an anisotropic parallel fiber structure, all-directional high-strength support is provided for the material, particularly, the bonding strength in the direction perpendicular to the working face is greatly improved, and the layering risk is eradicated; the combined action of mechanical interlocking and metallurgical bonding is formed, the interface bonding strength is far better than that of a traditional process, the layering problem is fundamentally solved, the vertical bonding strength is improved, a stable three-dimensional structure is achieved, the material is evenly abraded instead of flaked stripping under arc erosion, and therefore the electric service life of a product is greatly prolonged, and the service life of the product is prolonged. The firm three-dimensional skeleton solves the process problem of easy cracking in rolling under high carbon content, so that the carbon content can be stably increased to 6% or even higher. On the premise of keeping the same performance, the consumption of precious metal silver is effectively reduced, and the material cost is remarkably reduced.

This disclosure discloses a terminal contact spring and a switch, belonging to the field of electrical structures. The terminal contact spring includes: a contact segment, a connecting segment, a first constraint segment, and a second constraint segment connected in sequence. The contact segment is located on one side of the connecting segment, and the first and second constraint segments are located on the other side of the connecting segment. The side of the contact segment facing away from the connecting segment has a contact. The first constraint segment can constrain its own displacement in a first direction, and the second constraint segment can constrain its own displacement in a second direction. The first and second directions are located in the same plane and form an angle between them. The plane containing the first and second directions is parallel to the plane containing the elastic deformation trajectory of the contact segment. This disclosure can reduce arc erosion, ensure conductivity, and reduce safety hazards.

The invention provides a preparation method of a high-conductivity copper-based nano-composite contact material, the high-conductivity copper-based nano-composite contact material and application of the high-conductivity copper-based nano-composite contact material, the preparation method comprises the steps that a chemical co-reduction method is adopted to generate a nano-silver coating layer on the surface of copper powder in situ, graphene oxide is reduced at the same time, and silver-coated copper / reduced graphene oxide composite powder is obtained; carrying out ultrasonic-assisted ball-milling mixing with nano aluminum oxide; performing spark plasma sintering; performing hot extrusion forming; and annealing treatment. The nano silver-graphene-copper gradient interface structure is constructed, the conductive performance and the arc ablation resistance are synergistically improved, the room temperature conductivity reaches 103-107% IACS, the tensile strength reaches 350-420 MPa, and the nano silver-graphene-copper gradient interface structure is suitable for electric power fitting connection wire clamps and connectors.

The invention discloses an arc erosion resistant hard alloy and a preparation method and application thereof. The hard alloy comprises 82-88% of WC, 8-12% of Co-Ni-Mn alloy, 1.5-3% of VC, 1-2% of Al2O3 and 0.5-1.5% of TiN, and the mass ratio of Co to Ni to Mn in the Co-Ni-Mn alloy is 6: 3: 1. According to the preparation method, VC, Al2O3 and TiN multi-element strengthening phases are coordinated and complemented, Co-Ni-Mn ternary binding phases are alloyed to resist high-temperature oxidation, and a homogeneous phase preparation process of high-energy wet grinding and segmented sintering is combined, so that the three properties of wear resistance, impact resistance and electric arc resistance of the mold are synergistically improved; the problems that an existing electrode mold is poor in arc erosion resistance, and abrasion resistance and impact resistance are difficult to consider at the same time are solved.

This invention relates to the field of electricity meter testing technology and discloses an electricity meter testing device. A push spring and an elastic support pin sleeve allow the conductive terminal to be inserted into the meter's wiring socket in a de-energized state. After the conductive terminal is fully aligned with the wiring socket, a pushing unit continues to move the meter, causing the switching component to connect the circuit. This ensures that the conductive terminal remains de-energized throughout the insertion process, fundamentally eliminating tip discharge and arc erosion caused by insufficient contact. It also avoids the formation of additional contact resistance due to oxidation on the conductive terminal surface, effectively eliminating problems such as current and voltage sampling jumps and inconsistencies between the tested meter and the standard meter current. This provides accurate and reliable assurance for the detection of meter measurement errors.

The invention discloses an arc ablation copper-tungsten contact material performance evaluation method, and belongs to the field of high-voltage switch equipment material testing. The method comprises the following steps: carrying out an ablation test on a material through a high-power pulse discharge system, and measuring a melting threshold value; mass loss before and after ablation is measured, and the ablation rate is calculated; a white light interferometer is used for collecting the three-dimensional shape of an ablation area, and the average melting depth is calculated; counting the maximum crack width of the surface by using a scanning electron microscope, and obtaining the maximum depth of the crack by observing the cross section; analyzing a microstructure by using back scattering electron diffraction, and counting a large-angle grain boundary proportion; and finally, selecting the six parameters as key indexes, and calculating a comprehensive performance score in combination with weight distribution. According to the method, a multi-dimensional evaluation system covering macroscopic thermal damage, surface topography characteristics and a microstructure is constructed, the limitation of single index evaluation is overcome, and accurate quantitative evaluation of arc ablation resistance and crack resistance of the copper-tungsten contact material is realized.

The invention relates to the technical field of electrical materials, in particular to an electrical contact for a direct current contactor and a preparation method thereof. The electrical contact comprises the following raw materials in percentage by weight: 2-8% of tin ingots, 1-5% of indium ingots, 0.05-1% of rare earth ingots and the balance of silver ingots. An alloy ingot-oxidation method or an alloy powder-powder oxidation method is adopted for preparation. The alloy ingot-oxidation method comprises the steps of smelting, hot extrusion, pure silver layer compounding, oxidation and the like, the alloy powder-powder oxidation method comprises the steps of atomization powder preparation, pre-oxidation, isostatic pressing and the like, and finally the AgSnO2-In2O3-REO electrical contact is prepared. According to the electric contact, high conductivity, arc erosion resistance and balance of stable contact resistance are achieved through the ternary composite reinforced phase, the electric contact is matched with a high-power direct-current contactor, the double-process route considers precision and mass production requirements, and the industrialization prospect is wide.

This invention discloses a TaB2 / Cu composite material for electrical contacts and its preparation method. The composite material, by mass percentage, comprises 95-99.5% Cu and 0.5-5% TaB2. The preparation method includes: independently melting Cu-Ta master alloy, Cu raw material, and B raw material, followed by in-situ reaction to obtain a cast TaB2 / Cu composite material; hot forging the cast TaB2 / Cu composite material followed by cold rolling; and finally annealing the cold-rolled material. This invention introduces TaB2 ceramic particles into a copper matrix, combining the high melting point, high strength, and arc erosion resistance of the boride ceramic phase with the high conductivity of pure copper, resulting in a copper-based composite material with high conductivity, low mass loss, and stable contact resistance.

This invention discloses a thermally reduced in-situ grown graphene-reinforced silver-nickel electrical contact material and its preparation method. By adding submicron-sized nickel powder and a small amount of graphene oxide to silver powder, followed by ultrasonic-stirring synergistic pretreatment, ball milling, and vacuum hot-pressing sintering, the nickel powder spontaneously constructs a high-strength three-dimensional network framework at high temperatures, significantly improving the structural stability of the matrix. Simultaneously, it promotes the rapid thermal reduction of graphene oxide to reduced graphene oxide, which selectively adheres to the nickel surface. In this structure, the nickel framework effectively suppresses material splashing and loss under arc ablation, while the thermally reduced in-situ generated reduced graphene oxide significantly reduces contact resistance, improves charge transport efficiency, and enhances resistance to arc erosion due to its excellent thermal stability and lubricity. This invention achieves a simultaneous breakthrough in high conductivity and arc resistance through the dual synergistic mechanism of the nickel framework and reduced graphene oxide. Furthermore, the process is simple, with low industrial mass production costs, and it has promising industrial application prospects.

The application discloses an explosion-proof microswitch, which comprises a shell, a knob assembly, a contact system, a first contact leg and a second contact leg, and the knob assembly comprises a button and a push rod. A first permanent magnet ring and an arc separation plate are arranged at the bottom of the button, a second permanent magnet ring is arranged at the top of the push rod, and the two permanent magnet rings are opposite to each other and have the same polarity to form a magnetic suspension gap to realize non-contact transmission. An annular concave surface of a mounting hole of the shell is matched with the arc separation plate, and an annular stepped surface is welded with a bellows to form a static seal. In the contact system, a ceramic insulating partition plate is arranged between a movable contact and a static contact, an elastic element is connected with a transmission piece in a through hole, and the movable contact indirectly contacts the static contact through the transmission piece. The explosion-proof microswitch is provided with a magnetic suspension transmission structure, a multiple sealing arc separation structure and an elastic buffer contact structure, mechanical wear and invasion of dangerous medium are avoided, contact bounce and arc erosion are reduced, explosion-proof safety, action reliability and service life are improved, the explosion-proof microswitch is suitable for high-risk scenes and meets the miniaturization requirement.