183 results about "Electrolytic corrosion" patented technology

To provide an electric corrosion preventing electric conductive cover and a rolling bearing which can prevent electric corrosion to lengthen a service life thereof.SOLUTION: An electric corrosion preventing electric conductive cover 1 has: a bearing fitting part 9 having a cylindrical part fitted in a first bearing ring 3 of a rolling bearing 2 and having electric conductivity; and an electric conductive part 10 radially extending from the bearing fitting part 9 to come into contact with a second bearing ring 4 of the rolling bearing 2 and having electric conductivity. A rolling bearing 2 includes the electric corrosion preventing electric conductive cover 1.SELECTED DRAWING: Figure 2

The invention discloses a method and system for regulating and controlling the volume fraction of variants in high-temperature alloy and a medium, and relates to the field of material science and engineering.The method comprises the steps that grain orientation data of any target high-temperature alloy sample is obtained, and a finite element model is constructed; obtaining the volume fraction of each variant in the target high-temperature alloy sample after electrolytic corrosion; performing a tensile experiment on any target high-temperature alloy sample at different temperatures and different tensile rates to obtain material attributes and a real stress-strain curve of the target high-temperature alloy; performing tensile simulation and creep simulation on the target high-temperature alloy in sequence by utilizing finite element software imported with a finite element model and a crystal plasticity constitutive model, and determining an optimal working condition corresponding to an expected variant volume fraction in the target high-temperature alloy; and under the optimal working condition, the target metal alloy is subjected to heat treatment through a creep stretching machine, and the target high-temperature alloy with the expected variant volume fraction is obtained. The volume fraction of the variants in the high-temperature alloy can be accurately regulated and controlled.

The invention discloses a vibration-CO2 corrosion coupling effect real-time monitoring system and monitoring method for a well cementation cement sheath of an oil and gas well in a high-temperature and high-pressure environment. The system comprises a kettle system which is fixed with a base of an axial loading system, and a push rod of the axial loading system extends into the kettle system from the center of a kettle cover and is pressed on a detected body; the CT detection system is mounted below a jack supporting plate of the axial loading system; the electrolytic corrosion system is connected with the lower end of a first embedded axial pipeline on the side wall of a kettle body in the kettle system so as to apply an experimental environment; the gas pressurization system is divided into two paths, one path is led into the kettle system from the lower part, and the other path is connected with the lower end of the second embedded axial pipeline; a sleeve of the kettle system is fixed in the kettle system, the nondestructive testing system is installed in the middle of the sleeve, and the vibration system in the sleeve is installed on the lower portion of the sleeve. According to the invention, axial loading, gas pressurization and heating devices are integrated, and an underground high-temperature and high-pressure environment is simulated; and CT and ultrasonic waves cooperate to realize multi-dimensional dynamic monitoring of the corrosion process.

The invention relates to the technical field of advanced manufacturing of metal materials. A metallographic analysis method for detecting fine Laves phases in homogenized GH4169 alloy can clearly display the average particle size, the area proportion and the spatial distribution characteristics of the fine and dispersively distributed Laves phases by performing homogenizing heat treatment on as-cast GH4169 alloy and combining an optimized sample preparation process and an electrolytic corrosion technology. Compared with a traditional chemical erosion method, the method provided by the invention has higher detection precision, analysis efficiency, imaging quality and statistical reliability, and can realize accurate identification and quantitative analysis of trace Laves phases. The method is simple and convenient to operate, is suitable for evaluating the homogenization treatment effect and predicting the subsequent processing performance of the material, and provides a reliable basis for quality control and process optimization of the high-temperature alloy.

The invention relates to a corrosive agent and a corrosion method for displaying a 32CrNi3MoVE crystal boundary of alloy steel, which are characterized in that a common chemical product is used as an electrolytic corrosive agent after being simply proportioned, and the 32CrNi3MoVE steel quenched and tempered state original austenite crystal boundary is clearly displayed by a proper corrosion method. Chemical reagents used by the corrosive are economical and applicable, the corrosive is composed of alum, oxalic acid, dishwashing liquid, distilled water and the like which are existing in a laboratory, the proportioning of the corrosive is the key, the electrolytic corrosion method is simple to operate, alum can effectively display the grain boundary, oxalic acid provides a weak acid environment for oxidation reduction, and the corrosion effect is good. The dishwashing liquid slows down the corrosion rate of weak acid electrolyte to a metallographic specimen, weakens structure display, and improves the definition of crystal boundary display. The corroded sample is lightly polished in a polishing machine, and the corrosive agent ratio and the electrolytic corrosion method are combined to form an efficient novel corrosion method. The traditional corrosive agent capable of completely replacing saturated picric acid and a proper amount of detergent and the corrosion method effectively solve the problem of 32CrNi 3MoVE steel quenched and tempered state original austenite grain boundary display.

To provide a compact current-carrying unit suitable for use in an oil bath, and to provide a bearing unit with an electrolytic corrosion preventive effect.SOLUTION: A current-carrying unit 2 includes a conductive annular case body part 6, a conductive energization member 7 that protrudes radially inward from the case body part 6, and an elastic member 8 that biases the energization member 7 radially inward. The case body part 6 is configured such that oil holes 15 and 16 are formed to allow a lubricant to flow in an axial direction. The bearing unit 1 includes the current-carrying unit 2, and a bearing 3 having an outer ring 22, an inner ring 23 disposed on an inner diameter side of the outer ring 22, rolling elements 24 provided between the outer ring 22 and the inner ring 23, and a retainer 25 that holds the rolling elements 24 at predetermined intervals in a circumferential direction. The current-carrying unit 2 and the bearing 3 are both integrally configured by having the former fitted into the latter.SELECTED DRAWING: Figure 1

This product is a bearing plate that is installed at the intersections of rope materials such as wire ropes arranged in a grid pattern on a slope to prevent surface collapse. It consists of a round washer with a reinforcing tube, a rope material external slippage prevention body, and a pressure receiving body. The product is attached to a rock bolt driven into the intersection of the rope material, and the rope material is wound around the pressure receiving body. The rope material external slippage prevention body and pressure receiving body are made of resin material, which prevents electrolytic corrosion caused by contact with the rope material and makes the product lightweight.

The application provides a flat POGO PIN female head connector, which comprises a stainless steel back shell, a plastic front cover and a plastic upper cover arranged at the lower end and the upper end of the front side of the stainless steel back shell respectively, three upper stretch terminals equidistantly arranged on the plastic upper cover, three lower stretch terminals equidistantly arranged on the plastic front cover, and a plastic body integrally injection molded on the upper stretch terminals and the lower stretch terminals; the surface of the upper stretch terminals is sequentially plated with a nickel base layer, a palladium-nickel alloy layer and a gold layer, the surface of the contact area of the lower stretch terminals is sequentially plated with a nickel base layer, a gold layer, a platinum alloy layer, a palladium-nickel alloy layer and a platinum alloy layer to form an anti-electrolytic corrosion plating layer; the end of the upper stretch terminal is provided with a cantilever, and the ends of the three cantilevers are stacked and riveted with a flat plate part; and the front side of the plastic front cover is a flat surface. The flat POGO PIN female head connector realizes quick mutual matching, high-reliability power supply and signal transmission.

The invention discloses a method for establishing an inclusion-containing metal rotation bending fatigue life prediction model. A certain metal is selected, a fatigue life model directly related to the actual width or diameter of the inclusion is established through metallographic sample preparation, electrolytic corrosion, SEM / EDS detection, a rotating bending fatigue test and the like, and gaps which are neglected by a traditional metallographic inclusion detection method all the time and are formed around the inclusion and are also unfavorable for the fatigue performance of the metal are considered. By adopting the model, the actual width or diameter of the inclusion obtained by a traditional metallographic inclusion detection method can be used for directly predicting the rotating bending fatigue life of the metal, so that more convenient and accurate guidance is provided for selection of a smelting process in a metal production process and control of the inclusion.

The invention relates to a pretreatment process for accurate measurement of a metal element of a cooling water system through an electrochemical corrosion weight loss method and application of the pretreatment process, and the pretreatment process comprises the following steps: S1, placing a sample in flowing distilled water, and carrying out mechanical cleaning by using a banister brush; s2, vertically immersing the sample into an acid solution for a set time, wherein the set time is determined according to the material of the sample; and S3, washing the surface of the sample by using distilled water and alcohol in sequence, drying the sample, cooling to room temperature, and weighing. Compared with the prior art, system errors caused by product residues, film layer differences or excessive acid pickling can be remarkably reduced, and weight loss data are closer to the real electrolytic corrosion amount.

The invention discloses an unsealing method for a commercial plastic package device containing a Cu lead. The unsealing method specifically comprises the following steps: determining the highest position of the Cu lead of the plastic package device and a bonding point distribution area by adopting X rays; grooving the positioning window area of the plastic package material on the upper surface of the device by adopting a laser ablation method; controlling the thickness of the molding compound above the highest part of the Cu lead within a proper range by combining X rays; performing electrolytic corrosion on the plastic package material at the bottom of the slotted window area by adopting a mixed solution of fuming nitric acid and concentrated sulfuric acid, decomposing the epoxy resin, and retaining the ceramic filler; dissolving the residual mixed solution of fuming nitric acid and concentrated sulfuric acid with acetone; removing the ceramic filler by using deionized water; isopropanol is adopted to keep the device dry; and an SEM scanning electron microscope is adopted to judge the reliability of the Cu lead and the Cu lead / Al bonding pad after electrolytic corrosion. According to the invention, the corrosion to the plastic package material is accelerated, and the problem that the commercial plastic package device containing the Cu lead cannot be efficiently etched under the standard requirement in the prior art is solved.

The invention discloses a method for accurately measuring the phase content in stainless steel. The method is suitable for stainless steel containing at least one phase of ferrite, austenite, cementite and martensite. The method comprises the following steps: S1, cutting, grinding and polishing a stainless steel sample to obtain a bright surface; s2, pre-judging the type and the number of contained phases through metallographic structure observation in combination with component analysis and a heat treatment process; and S3, directional detection is conducted according to the pre-judgment result, ferrite is measured through metallographic software after being subjected to electrolytic corrosion through a KOH electrolyte, austenite is measured through an X-ray diffraction technology, cementite is measured through a laser confocal microscope after being subjected to acid etching, and martensite is obtained by subtracting the sum of the measured phase content by 100%. The method integrates various technical advantages, is simple and convenient to operate, wide in detection range and high in precision, and can provide accurate data support for stainless steel process optimization and material development.

Provided are: an automotive structural material that makes it possible to prevent chipping and electrolytic corrosion without using protection tape, obviates having to adjust unevenness for the purpose of painting, and moreover can be manufactured in a short time; and a method for manufacturing the automotive structural material. The present invention pertains to an automotive structural material that contains carbon-fiber-reinforced plastic, the automotive structural material having a base layer 3 composed of a cured sheet-molding compound 1 containing staple carbon fiber and a thermosetting resin, and a protective layer 4 that is laminated on the base layer 3 and is composed of a cured glass paper prepreg 2 or a glass cloth prepreg containing glass fiber and a thermosetting resin, the base layer 3 and the protective layer 4 being integrally cured.

To provide a bearing which can maintain an excellent electric corrosion suppression effect for a long period of time compared to the case where an insulation film is formed on an outer ring or an inner ring.SOLUTION: A rolling bearing for preventing an electric corrosion according to the invention includes: an outer ring 101; an inner ring 102; a rolling element 103; and an insulation cover 111 covering an outer side of the outer ring 101 and an insulation cover 121 covering an inner side of the inner ring 102. An alumite coating is formed on surfaces of the insulation covers 111, 121, and includes: cylindrical parts 111a, 121a along an outer peripheral surface 101a of the outer ring 101 and an inner peripheral surface 102a of the inner ring 102; annular parts 111b, 121b curved along one end faces 101b, 102b of the outer ring 101 and the inner ring 102 respectively by a press molding on one end of the cylindrical parts 111a, 121a; and caulking parts 111c, 121c curved by caulking along the other end faces 101c, 102c of the outer ring 101 and the inner ring 102 from the other end of the cylindrical parts 111a, 121a.SELECTED DRAWING: Figure 1

To suppress the current flowing between an outer ring and an inner ring via rolling elements in a rolling bearing, thereby preventing the occurrence of electrical corrosion.SOLUTION: A first rolling bearing 10A includes an outer ring 11, an inner ring 12, rolling elements 13, a conductive member 15 fixed to the outer ring 11 and slidingly contacting the inner ring 12, and a covering member 50 that covers an outer circumferential surface 11a and an end face 11b of the outer ring 11 and an annular groove 23 in the outer ring 12 serving as a mounting portion for the conductive member 15. The covering member 50 includes an insulating layer 51 in contact with the outer ring 11, and a conductive layer 52 arranged on the side opposite to the side of the insulating layer 51 that contacts the outer ring 11. The insulating layer 51 is insulating, and the conductive layer 52 is conductive.SELECTED DRAWING: Figure 2

The invention provides a large-shaft-diameter motor grounding carbon brush device. The large-shaft-diameter motor grounding carbon brush device comprises a rotor main shaft; the grounding ring is arranged on the outer side of the rotor main shaft, and the grounding ring is provided with at least one mounting hole; the carbon brush assembly is arranged between the outer ring of the rotor main shaft and the inner ring of the grounding ring, the carbon brush assembly comprises at least one carbon fiber bundle, two end parts of the carbon fiber bundle are overlapped and connected in the same direction to form a fixing part, a bending part and a connecting part for connecting the bending part and the fixing part, and the fixing part is fixedly connected to the mounting hole and externally connected with the grounding end; at least part of the bending part is used for being in contact and conductive connection with a rotor spindle, and spindle current is introduced into the grounding end through the connecting part and the fixing part in sequence. The shaft electric corrosion prevention device can be in stable contact with a rotor main shaft for electric conduction, can reduce shaft voltage to realize a shaft electric corrosion prevention function, and is particularly suitable for large-shaft-diameter high-linear-speed motors.

The invention belongs to the technical field of three-dimensional atomic probes, and specifically is a stirring device for electrolytic polishing of a three-dimensional atomic probe, comprising a stirring base, a motor, a vertical rod, a synchronous wheel, a synchronous belt, a turntable, a driving magnet, an electrolytic barrel, a tempered glass half shell, a sealing ring and a driven magnet; the motor drives the synchronous wheel to rotate, and through the transmission of the synchronous belt, a plurality of synchronous wheels are synchronously rotated, which drives a plurality of vertical rods to rotate synchronously, drives the turntable to rotate, and causes two driving magnets on the turntable to rotate, and through the mutual attraction between the driving magnet and the driven magnet, drives a stirring bar to rotate in the middle of the bottom surface of the electrolytic barrel, drives the electrolyte inside the electrolytic barrel to rotate, so that the electrolyte always keeps a moving mixed state, so that the concentration of each part of the electrolyte is kept consistent, and then the electrolytic corrosion degree of the surface of the sample is kept consistent, thereby reducing the probability of burrs on the surface of the three-dimensional atomic probe and improving the quality of the three-dimensional atomic probe.

This disclosure provides an electrolytic corrosion method for martensitic structures in FeMnSi alloys, relating to the field of materials processing technology. The method includes: pretreatment operations such as grinding and polishing the FeMnSi alloy; mixing sodium hydroxide, sulfuric acid, and water to obtain an electrolyte for electrolytic corrosion; placing the pretreated FeMnSi alloy as the anode and a stainless steel plate as the cathode in an electrolytic cell containing the electrolyte to perform the electrolytic corrosion process; after the electrolytic corrosion process, removing the FeMnSi alloy, cleaning, and drying it. This disclosure can obtain a well-defined microstructure, meeting the needs of microscopic observation and analysis.

To provide a method for evaluating the electrical corrosion resistance of a rolling bearing, the method making it possible to easily and appropriately evaluate whether the rolling bearing has electrical corrosion resistance capable of preventing occurrence of ridge marks under certain operating conditions.SOLUTION: The method includes: a test step (S1) of applying a predetermined voltage to a rolling bearing in a state where an inner ring and an outer ring rotate relative to each other; an investigation step (S2) of searching a first raceway surface and a second raceway surface after completion of the test step for an abnormal surface portion generated when a single discharge occurs between the first raceway surface or the second raceway surface and rolling elements; and an evaluation step (S4) of determining that the rolling bearing is capable of generating ridge marks due to electrical corrosion on one of the first raceway surface and the second raceway surface when the abnormal surface portion consisting of discharge marks formed in an uneven pattern is found in the investigation step, and determining that the rolling bearing does not generate ridge marks when the discharge marks are not found in the investigation step.SELECTED DRAWING: Figure 1

A motor device prevents electrolytic corrosion of a bearing. The motor device is mounted on a vehicle and has a stator installed in a housing and provided with a concentrated winding coil, a rotor housed in the center of the stator and provided with a permanent magnet, a bearing installed in the housing and supporting a rotating shaft of the rotor, an inverter provided between the stator and a power storage body and controlling an energization state of the concentrated winding coil, and an energization control section that outputs a control signal to the inverter and executes field weakening control that generates a magnetic flux of the concentrated winding coil in a direction to weaken a magnetic flux of the permanent magnet. The energization control section executes the field weakening control to make a potential difference between the housing and the rotating shaft, i.e., shaft voltage Va1, lower than a withstand voltage Vb1 of the bearing when a motor revolution number Nm is greater than a threshold value Nx.

The utility model discloses an electrode for low-voltage micro-arc machining of a square hole, and particularly relates to the technical field of non-traditional machining, the electrode comprises a clamping part and a machining part, the machining part is fixedly communicated with the center position of the bottom end of the clamping part, a center through hole is formed in the center axis of the machining part, and the top end diameter of the center through hole is larger than the bottom end diameter. A spiral groove is formed in the center through hole, and a chip groove is formed in the outer side of the machining part. Scraps and waste residues generated in the machining process can be discharged through the three chip discharging grooves, meanwhile, the three chip discharging grooves can assist in heat dissipation and prevent a machining area from being overheated, and therefore a machining part and a workpiece are protected, the flow path of fluid can be changed through the special geometrical shape of the spiral grooves, and the machining efficiency is improved. Therefore, the fluid speed is increased to strengthen the fluid dynamic arc breaking effect, the discharging effect of the inner flushing liquid on interelectrode electric corrosion products is improved, the structure is simple, the electric corrosion products can be conveniently discharged, and the loss of a machining part is effectively reduced.

The utility model discloses ultrahigh-voltage corrosion foil production equipment based on an aluminum electrolytic capacitor. The ultrahigh-voltage corrosion foil production equipment comprises a workbench and a guide mechanism, seven transmission rollers are rotationally connected into the workbench, an electrolytic tank is arranged at the lower end of the workbench, graphite electrodes are arranged at the front end and the rear end of the electrolytic tank, conductive rollers which are symmetrically distributed are rotationally connected to the middle of the electrolytic tank, and a support is arranged at the rear end of the upper surface of the workbench; the guide mechanism is arranged between the workbench and the support; the ultrahigh-voltage corrosion foil production equipment further comprises a control switch set, the control switch set is arranged in the middle of the right side surface of the workbench, the input end of the graphite electrode and the input end of the conductive roller are both electrically connected with the output end of the control switch set, and the graphite electrode is a cathode. Efficient drying after electrolytic corrosion of the ultrahigh-pressure corrosion foil can be achieved, water vapor is effectively prevented from falling back to the upper end of the ultrahigh-pressure corrosion foil, and the product effect of the ultrahigh-pressure corrosion foil is effectively improved.

The application discloses a kind of corrosion methods for revealing alloy sample metallographic structure, comprising: step S1, preparation electrolytic etchant: using oxalic acid, sodium bicarbonate and concentrated nitric acid preparation final concentration is 0.25-0.5mol / L sodium oxalate and 0.15-0.3mol / L nitric acid mixed aqueous solution;Step S2, electrolytic etching of corrosion piece: electrolytic etchant is poured into electrolytic etching instrument, and the alloy sample to be corroded is placed in electrolytic etching liquid and electrolytic etching is carried out.The electrolytic etchant of the application uses oxalic acid, sodium bicarbonate and concentrated nitric acid as reactant, and is prepared by chemical ion reaction.After the preparation of etchant is finished, a small amount of carbonate ions and hydrogen ions are still stored in the etchant, so that a small amount of carbonate ions and hydrogen ions will continue to react when the alloy sample is electrolyzed, and micro-bubbles are attached to the alloy sample, so that the metallographic photo taken has stereoscopic imaging effect, and the grain boundary is clear and identifiable.

The invention discloses an austenite grain size display method of Cr-Mo-V series hot work die steel, and belongs to the technical field of metal material metallographic inspection. The austenite grain size display method of the Cr-Mo-V series hot work die steel is provided for solving the problem that grains of the Cr-Mo-V series hot work die steel in a spheroidizing annealing state are difficult to clearly and completely display, and comprises the steps that low-temperature austenitizing treatment is conducted; performing high-temperature tempering treatment; grinding, mechanical polishing, electrolytic corrosion and light polishing are carried out; and gradient circulation treatment is conducted, and the electrolytic corrosion voltage, the electrolytic corrosion time and the light polishing time are controlled to be gradually reduced. According to the method, the oxalic acid aqueous solution is adopted for electrolytic corrosion, the contrast difference between the grain boundary and the matrix is strengthened through the stepped circulating electrolytic corrosion and light polishing method, the austenite grain boundary is displayed more clearly, the clear and high-contrast grain boundary morphology is obtained, and accurate grain size rating is facilitated.

The utility model provides a battery pack, which is characterized in that the peripheral parts of a conductive shell and a conductive cover are connected with each other, a battery module is accommodated in a space defined in the shell and the cover in a state of being insulated from the shell and the cover, and the shell and the cover are connected through a conductive component to be conducted. The periphery of the housing and the periphery of the cover are sealed by an insulating sealing member over the entire periphery at a position closer to the outer peripheral side than the connection portion of the housing and the cover to the conductive member. Thus, when the case and the cover are short-circuited with the battery module, the case and the cover can be electrically conducted to achieve equipotential, and electrolytic corrosion of the conductive portion of the case and the cover can be suppressed.

To provide a rolling bearing that achieves high performance in resistance to electrical corrosion.SOLUTION: A rolling bearing 1 has a metallic inner ring 2, a metallic outer ring 3, rolling elements 4 arranged between the inner ring 2 and the outer ring 3, and a conductive seal 6 for sealing the internal space between the inner ring 2 and the outer ring 3. The conductive seal 6 comprises a conductive rubber 61 and a plate-like core metal 62, wherein an end on the inner ring 2 side and an end on the outer ring 3 side of the conductive rubber 61 are held against the inner ring 2 and the outer ring 3 by the restoring force of the conductive rubber 61. The core metal 62 is fixed to the rolling element 4 side of the conductive rubber 61, and at a bent portion 621 formed by bending an end of the core metal 62 on the outer ring 3 side, a plate face of the core metal 62 directly contacts the outer ring 3.SELECTED DRAWING: Figure 1

The invention provides an electrolytic corrosion liquid and a display method of maraging steel original austenite grain boundaries, and relates to the technical field of physicochemical metallographic detection.The method comprises the steps that firstly, component design is conducted on the basis of a CALPHAD method, maraging steel is prepared through an injection molding method, and the original austenite grain boundaries are represented through electrolytic corrosion; the electrolytic corrosion liquid comprises the following components: 5-6 ml of absolute ethyl alcohol, 2-3 ml of concentrated nitric acid, 1.5-2.5 ml of hydrochloric acid, 2-2.5 ml of deionized water, 1-2 g of copper sulfate and 1-2 g of copper chloride, the electrolysis voltage is 8-10 V, the electrolysis current is 2-5 A / cm < 2 >, electrolysis is performed 2-4 times, and the electrolysis time is 8-12 s each time. According to the method, the grain boundary of the original austenite can be accurately and clearly observed by preparing the components of the corrosive liquid, so that the grain size of the austenite is further determined, and the method has important significance in counting the grain size of the austenite and efficiently and accurately obtaining experimental data.

A fuel cell includes an anode separator and a cathode separator each including a coating on its surface. Each of the anode and cathode separators includes: a body; a coolant manifold that is an opening in the body and that is configured to allow a coolant to flow therethrough; an intra-cell sealing portion that provides a seal between the anode and cathode separators within the fuel cell and that is provided by the body being bonded to the insulating sheet so as to surround the coolant manifold; and a sacrificial electrolytic corrosion portion disposed between the coolant manifold and the intra-cell sealing portion and including a plurality of exposed portions where a base material is exposed without being covered with the coating. The sacrificial electrolytic corrosion portion includes at least one of the exposed portions on a straight line connecting the coolant manifold and the intra-cell sealing portion.

The invention discloses an electric-corrosion-resistant tungsten alloy contact material. The electric-corrosion-resistant tungsten alloy contact material comprises tungsten powder, copper powder and an additive, wherein the substance mass ratio of the tungsten powder to the copper powder to the additive is (93-97): (4.9-2.1): (2.1-0.9). The tungsten alloy contact material is prepared by blending tungsten powder, copper powder and an additive, meanwhile, scandium-cerium continuous effect liquid in the additive and a titanium boride agent are subjected to stirring improvement treatment, and carbon nanotubes, zirconium oxide, a silane coupling agent KH550 and a dopamine hydrochloride solution in the continuous effect liquid are blended and matched; according to the titanium boride agent obtained by blending titanium boride with samarium chloride and graphene, through synergistic improvement and co-coordination of the raw materials, the obtained additive optimizes the ablation resistance, strength performance and hardness coordination of the product in a system, and the temperature change resistance stability effect of the product is remarkable.

To provide a gear device that restrains electrolytic corrosion.SOLUTION: A gear device 1 is installed in a railroad vehicle, and transmits a turning force transmitted from an electric motor, to an axle. The gear device 1 comprises a gear wheel 12, and a first insulation member 13 having insulation performance. A through hole 12a into which the axle is inserted is formed in the gear wheel 12. The gear wheel 12 rotates integrally with the axle when the turning force is transmitted from the electric motor. The first insulation member 13 is provided on a wall surface 12b of the through hole 12a of the gear wheel 12, and electrically insulates the gear wheel 12 and the axle.SELECTED DRAWING: Figure 3