59 results about "Silver plate" patented technology

The invention discloses a material with a silver coating for low-temperature brazing of brazing filler metal, and particularly relates to the field of brazing welding, which comprises the following steps: silver amalgam paste is prepared by oscillating and mixing silver powder and mercury according to the mass ratio of 1: 9-0.5: 9.5 in a manner and method for plating silver on the surface of base metal (metal, semiconductor, ceramic or glass); when brazing is carried out, the surface of the silver plating layer of the to-be-welded piece is coated with brazing filler metal, and then heating and pressurizing are carried out in a low-temperature interval of 120-350 DEG C in a vacuum, protective atmosphere or atmospheric environment to complete connection. According to the method, the amalgam reaction and isothermal solidification principles are utilized, a tough welding spot mainly comprising a silver-based solid solution is finally formed, generation of a large number of brittle intermetallic compounds is avoided, a connector has high strength, high reliability and excellent thermal fatigue resistance, and therefore the problems that gold-tin brazing filler metal is high in cost, the brittleness of the welding spot is large, and the welding temperature is high are successfully solved.

The invention discloses a method for chemically plating silver on the surface of a nickel-plated ceramic copper-clad substrate, and relates to the technical field of metal surface treatment. The preparation method comprises the following steps: S1, sequentially adding nitric acid, imidazole and a surfactant into deionized water, and uniformly mixing to obtain an activating agent; s2, after the ceramic copper-clad substrate is pretreated, chemical nickel plating treatment is carried out, cleaning and drying are carried out, and a nickel-plated ceramic substrate is obtained; and S3, the nickel-plated ceramic substrate is immersed in an activating agent for activating treatment, chemical silver plating treatment and post-treatment are conducted, and a product is obtained. According to the method provided by the invention, the problem of copper ion migration in the later silver welding process of chemical silver plating on the surface of the ceramic copper-clad substrate can be solved, and the performance of the packaging module is improved.

The invention provides double-silver coated glass capable of being tempered in different places and a preparation method of the double-silver coated glass, and relates to the technical field of coated glass. The invention provides double-silver coated glass capable of being tempered in different places, which comprises a glass substrate, the bottom dielectric combination layer, the first Ag functional layer, the first metal sacrificial layer, the middle dielectric combination layer, the second metal sacrificial layer, the second Ag functional layer, the third metal sacrificial layer and the top dielectric protection combination layer are sequentially deposited on the surface of one side of the glass substrate from inside to outside. Each of the bottom dielectric combination layer and the middle dielectric combination layer is formed by laminating more than two dielectric layers; the top layer dielectric protection combination layer is formed by laminating more than two dielectric layers and a top layer protection layer, and the top layer protection layer is located at the outermost layer. The double-silver coated glass provided by the invention has excellent high-temperature resistance and supports remote tempering and laminated processing treatment, and the tempered product has excellent performance; and an excellent heat insulation effect is achieved.

The application discloses a copper wire silver plating drying equipment, and relates to the field of copper wire, which comprises a drying box, an unwinding roller and a winding roller, a wire inlet and a wire outlet are respectively arranged on the drying box at the unwinding roller and the winding roller, a tooth ring frame is reciprocatingly arranged on the outer wall of the drying box at the unwinding roller, one end of the tooth ring frame is connected with a tooth rod, a cleaning ring matched with the tooth rod is rotatably arranged in the wire inlet, and a plurality of conveying rollers are staggered arranged in the drying box. The cleaning ring is reciprocatingly rotated, so that the outer wall of the silver-plated copper wire is cleaned while the copper wire is unwound, the silver-plated copper wire does not contact each other in the conveying process, the residual heat in the drying chamber is discharged into the cooling chamber under the action of the heat exhaust pipe, so that the temperature is prevented from suddenly changing to cause cracks or stress concentration on the surface of the copper wire, and the heating power of the heating wire is greatly reduced.

A cadmium-free, low-silver solder is characterized by its composition, by mass percentage, of 4.0% to 5.0% Ag, 40.0% to 45.0% Zn, 11.0% to 13.0% Sn, 0.5% to 1.5% In, 0.5% to 1.5% Ga, 0.5% to 1.5% Ni, 0.01% to 0.05% nano-CeO2, 0.01% to 0.05% nano-Y2O3, and the balance being Cu. Silver plates, cathode copper, zinc ingots, tin ingots, metallic indium, metallic gallium, and metallic nickel are added in the appropriate proportions and smelted using a medium-frequency smelting process. Before casting, trace amounts of nano-CeO2 and nano-Y2O3 powders are added, thoroughly stirred, and then cast into an ingot. The desired solder wire is then obtained through extrusion and drawing. The solder has a solidus temperature of ≤735°C and a liquidus temperature of ≤780°C. When used with the commercially available FB102 flux, the brazing performance of the brazing filler metal is close to that of the commercially available BAg25CuZn filler metal. When brazing copper-stainless steel, copper-brass, brass-stainless steel, and Q235 steel-stainless steel, the shear strength of the brazed joints is superior to that of the commercially available BAg25CuZn filler metal.

The production process of the photovoltaic V-shaped composite welding strip comprises the steps of prefabrication of an alloy copper strip, prefabrication of an alloy aluminum strip, prefabrication of alloy calcium powder and synthesis and mold pressing processes. The prefabricated alloy calcium powder, the alloy aluminum strip and the alloy copper strip are compounded and subjected to mould pressing through a synthesis mould pressing process, and the inclined grain V-shaped composite welding strip with inclined grains on the A surface is synthesized; the sloping grain V-shaped composite welding strip is subjected to surface cleaning, tin plating on the surface B and silver plating on the surface A to obtain the photovoltaic V-shaped composite welding strip. The photovoltaic V-shaped composite solder strip has the beneficial effects that the photovoltaic V-shaped composite solder strip manufactured by adopting the production process is low in cost, high in conductivity, low in failure rate, low in use and maintenance cost and long in service life; the cost of photovoltaic products can be reduced, application and popularization of the photovoltaic products are promoted, and immeasurable beneficial effects are brought to development of ecological energy and environmental protection.

The utility model relates to the field of rhinestone production and processing, and provides a surface silver plating device for rhinestone production, and the surface silver plating device for rhinestone production comprises: a conveying rack for conveying plastic uptake sheets; the conveying frame is provided with a telescopic hook used for hanging the blister sheet. The silver plating mechanism is arranged under the conveying frame and used for plating silver on the surfaces of the rhinestones on the blister sheets; the draining mechanism is arranged under the conveying frame and used for draining the blister sheets and the rhinestones; the draining mechanism is provided with an air blowing piece used for air-drying the rhinestones. The device further comprises a heating part used for heating and drying rhinestones and an exhaust part used for absorbing harmful substances in air of the draining mechanism and the silver plating mechanism. According to the surface silver plating device for rhinestone production, the draining efficiency after silver plating can be improved, and meanwhile harmful substances are prevented from volatilizing, polluting the environment and affecting the health of workers.

This utility model discloses a selective silver plating device for terminal components, belonging to the field of silver plating technology. The key technical features include a U-shaped base with a liquid storage component fixedly connected to its top. Positioning rods are fixedly connected to the front and rear sides of the U-shaped base. The liquid storage component includes a storage tank, with vibrating cylinders fixedly connected to both sides inside the tank. A cover plate is movably connected to the top of the storage tank. A spraying component is slidably connected to the surface of the positioning rods. This invention solves the problem that existing silver plating devices struggle to guide the flow of the silver plating solution. In actual use, due to the lack of a spraying device, it is difficult to accurately adjust the flow direction of the silver plating solution according to the actual situation, resulting in the terminal components still needing to be completely immersed in the plating solution. This causes parts that do not need silver plating to be plated with silver, which not only wastes silver material and increases production costs but may also affect the quality of the finished product, reducing the practicality of the device.

The present invention provides a copper surface chemical silver plating solution, comprising 0.1-100 g / L of silver (II) pyridine-2-carboxylate, 0.1-10 g / L of a complexing agent, 0.1-100 mL / L of an organic acid, 0.5-10 g / L of a surfactant, 0.2-8 g / L of an accelerator, 5-100 g / L of a corrosion inhibitor, and water. The present invention improves the chemical silver plating solution formula and adopts divalent silver ions Ag. 2+ It has a higher redox potential and a fast oxidation deposition speed, which makes the silver ion deposition rate fast and the silver plating layer can be deposited thicker. At the same time, the deposition rate is fast, and the attack on the circuit side corrosion position is small, which can avoid side corrosion. By combining with other additives, the deposition rate of silver ions can be further accelerated, the deposition thickness can be increased, and side corrosion can be avoided, thereby solving the side corrosion problems of thin silver thickness and strong acid corrosion of copper surface in chemical silver plating in the existing technology.

The application specifically relates to a preparation method of a low-gas-content silver plate, comprising the following steps: S1, adding silver powder into a crucible to smelt into a silver liquid; S2, adding a blocky silver graphite solid into the silver liquid, the blocky silver graphite solid is dispersed into silver graphite powder at high temperature, the smelting temperature is reduced and heating is performed; S3, pouring the silver liquid into a mold, and cooling to obtain the silver plate. The blocky silver graphite scrap is used as a deoxidizer to remove oxygen in the molten silver liquid, one is that when the blocky silver graphite is placed on the surface of the high-temperature silver liquid, the blocky silver graphite is broken into silver graphite powder and covers the surface of the molten silver liquid, the silver graphite powder is in full contact with the silver liquid and continuously consumes oxygen in the silver liquid; two is that no impurity ions are introduced, and the purity of the silver plate is maintained; three is that the broken silver graphite powder of the blocky silver graphite scrap, since the graphite powder is micron-level or even nanometer-level powder, air gas is difficult to penetrate the silver graphite powder layer and enter the molten silver liquid, and further plays a role of air isolation.

1. Name of the designed product: Medallion (rotating tennis - brass plated with silver). 2. Use of the designed product: for collection and commemoration. 3. Design points of the designed product: in shape. 4. Picture or photo that best shows the design points: perspective view 1.

The utility model discloses a magnetic stirring device for a glass ornament silver plating tank in the technical field of magnetic stirring equipment, which comprises a magnetic stirring machine body and side plates, the side plates are fixedly connected to the front side wall and the rear side wall of the magnetic stirring machine body, and the upper sides of the inner side walls of the side plates are fixedly connected with springs. A first telescopic rod is connected to an inner cavity of the spring in a sleeved mode, a silver plating groove is fixedly connected to the tail end of the spring, a pushing rod is fixedly connected to the middle of the rear side wall of the silver plating groove, the tail end of the pushing rod penetrates through the side plate and extends to the rear side wall of the side plate, and a fixing table is fixedly connected to the rear side of the rear side wall of the side plate; the magnetic stirring device for the glass ornament silver plating tank is reasonable in structural design, the stirring effect can be improved, the stirring duration can be shortened, the production efficiency of glass products can be improved, solution splashing can be prevented, and solution waste is avoided.

The utility model discloses a ceramic pulse forming line, and relates to the field of electronic components. The problems that an existing ceramic pulse forming line is formed by multi-stage parallel connection of a plurality of capacitors and inductance elements, and the requirements for internal resistance, inductive reactance and the like of electronic elements are very strict are solved. Comprising a rectangular ceramic chip, the upper surface of the ceramic chip is provided with a rectangular silver sheet, the lower surface of the ceramic chip is provided with a rectangular silver sheet, and the length and the width of the rectangular silver sheet are smaller than those of the rectangular ceramic chip; and two ends of the rectangular silver sheet are respectively welded with a copper sheet terminal, the copper sheet terminals extend to the outer side of the ceramic chip, and the width of the copper sheet terminals is smaller than that of the rectangular silver sheet.

The utility model belongs to the technical field of electroplating devices, and relates to a combined type electroplating device for cavity type parts with locally-silvered excircles, which comprises a protective sleeve, a protective plug and a tool, the tool comprises a conductive contact piece, a bearing support and a main frame, the conductive contact piece is connected with the main frame, and the main frame is connected with the bearing support; the bearing support comprises a main shaft and supporting frames symmetrically connected to the two ends of the main shaft. The main shaft is vertically connected with the main frame, and the supporting frame is vertically connected with the main shaft and is parallel to the main frame; during use, a to-be-plated part is placed on the supporting frame, the protective sleeve is arranged on the middle outer circle face area of the to-be-plated part in a sleeving mode, and the protective plug is embedded into an upper end hole of the to-be-plated part. The mode of dip-coating peelable rubber for insulation protection is replaced, protection of the inner cavity and the middle outer circle face area of the cavity type outer circle local silver plating part is achieved, and local silver plating is conducted on the outer circle faces at the two ends.

The utility model discloses an intelligent silver plating tank for new energy automobile parts, and relates to the field of new energy automobile part processing, the intelligent silver plating tank comprises a plate surface, the two sides of the upper end of the plate surface are fixedly connected with mounting racks, the upper ends of the mounting racks are provided with drying assemblies, and the surface of the plate surface is provided with a silver plating box; and a circulating assembly is arranged in the mounting frame and comprises synchronous wheels rotationally connected to the inner side of the mounting frame, and the outer surfaces of the synchronous wheels are in transmission connection through a synchronous belt. By the adoption of the structure, parts enter the plating solution in the silver plating box along with the synchronous belt, silver plating is completed in the circulating moving process, and then the parts leave the silver plating box, so that the circulating moving silver plating process of the parts is achieved, and the parts can make uniform contact with the plating solution through circulating moving; the problems of different silver plating thickness, rough surface and the like caused by non-uniform flowing of the plating solution during silver plating at a fixed position are avoided, the silver plating quality is greatly improved, and the defective rate is reduced.

The invention relates to the technical field of stainless steel fastener surface machining, in particular to a nickel plating process which comprises the steps of S01, abrasive paper wiping and hanging; step S02, performing high-temperature ultrasonic oil removal; step S03, washing with water and electrolyzing; s04, water washing, copper polishing and first hydrochloric acid activation are carried out; s05, washing with water and ammonia nickel; s06, water washing, drying, secondary cathode electrolysis and secondary hydrochloric acid activation are carried out; s07, silver pre-plating and bright silver plating are carried out; s08, silver protection, water washing and drying; and step S09, appearance inspection and packaging. A nanoscale nickel crystal nucleus is formed through ammonia nickel treatment, so that the problem of plating layer cracking caused by stress concentration of a workpiece can be effectively avoided; by plating silver outside the nickel plating layer, the nickel plating layer can be effectively protected from being corroded, and the salt spray resistance of the workpiece is improved; the problems that in the prior art, a plating layer is extremely prone to falling off in a bending test, and the salt spray resistance is poor are solved.

The present invention relates to the technical field of material plating, and in particular to a contact support chemical silver plating device, comprising a bracket, a liquid cylinder and a silver plating mechanism. The liquid cylinder is mounted on the bracket, and is filled with silver liquid; the silver plating mechanism comprises a plurality of blades and a plurality of plating cylinders, wherein the plurality of blades can revolve and rotate in a vertical direction, and the blades and the plating cylinders are arranged in a one-to-one correspondence, and the plating cylinders can revolve and rotate in a vertical direction along with the blades arranged in correspondence therewith, and can rotate around their own axes. The contact support chemical silver plating device of the present invention is provided with a silver plating mechanism, and the rotation of the blades will stir the silver liquid in the liquid cylinder, and cause the plating cylinder rotatably mounted on the blades to rotate, and as the blades rotate, the silver liquid in the liquid cylinder will be subjected to the action of centrifugal force, so that the accumulated and blocked contact support surfaces can also be evenly plated, thereby achieving batch plating while improving the efficiency and quality of plating.

The present invention relates to a magnetic core inclined silver dipping device and a process method thereof. The magnetic core inclined silver dipping device comprises: a silver dipping plate having a plurality of accommodating cavities, each of the accommodating cavities being provided with an adhesive, and part of the magnetic core being fixed in the accommodating cavities by the adhesive; an inclined top piece comprising an inclined top base plate and a plurality of inclined top blocks protruding from the inclined top base plate, each of the inclined top blocks corresponding to each of the magnetic cores one by one; a silver dividing piece comprising a silver dividing base plate and a first silver dividing plate, a second silver dividing plate and a third silver dividing plate protruding from the silver dividing base plate, the first silver dividing plate being able to abut and slide against the outer side surface of the left plate, the second silver dividing plate being able to abut and slide against the inner side surface of the left plate and the inner side surface of the right plate, and the third silver dividing plate being able to abut and slide against the outer side surface of the right plate, thereby forming a thicker silver layer and preventing short circuit between the two coils.

The invention discloses a tool for connecting a TFT glass kiln electrode with a power source and a connecting method, and belongs to the technical field of TFT glass kiln electric heating. The tool comprises a tool body which is of a three-face rectangular frame structure with a blank top, and inward bent plates are arranged at the top ends of the two sides of the tool body. The three-side rectangular frame structure is matched with the outer side of the electrode; a tool inserting plate is movably arranged on the top of the tool body, and a pouring groove is formed in the tool inserting plate. A plurality of electrode connecting bolts with one ends extending out are arranged in the electrodes, and the electrode connecting bolts in one row are connected and fixed through electrode connecting pin shafts; the electrode connecting bolts are used for connecting the upper plate and the lower plate with the electrodes, and wiring terminals of the electrodes are arranged on the upper plate and the lower plate. Compared with the traditional silver plate connection, the tool-assisted connection mode can prolong the service life of the connection part, reduce the maintenance frequency and replacement cost, and further improve the stability and economical efficiency of the line body operation.

The utility model relates to the technical field of ceramic chip detection, in particular to a micro-contact silver-plated ceramic chip conduction detection device, which comprises a base, a clamp and a probe fixing piece, a detection part for placing a silver-plated ceramic chip to be detected and a fixing part for fixing the clamp are formed on the base, the detection part is provided with a first probe and a second probe, and the first probe and the second probe are arranged on the base. A third probe and a fourth probe are arranged on one side of the probe fixing piece, the other side of the probe fixing piece is fixed to the clamping end of the clamp, and the clamping end of the clamp is located above the detection part; according to the device, the four probes in the device can be connected with a low-resistance measuring instrument by adopting a Kelvin four-wire method so as to detect the conduction performance of the silver-plated ceramic chip, so that the good conduction performance between the front surface and the back surface of the silver-plated ceramic chip can be detected, and the problems existing in the silver plating process can be reflected in time.

The utility model relates to cable technical field, and disclose an easy bending type flat cable, including conductor layer, the outside fixed mounting of conductor layer has insulating buffer layer, the outside fixed mounting of insulating buffer layer has silver plated copper braid, the inside of insulating buffer layer evenly distributed has a plurality of micro air cavity, the outside fixed mounting of silver plated copper braid has aluminium -plastic composite tape. The easy bending type flat cable, the conductor layer adopts the silver plated copper conductor of multiple twisted formation conductor beam, cooperates the flexible isolation strip of silicone rubber material, both strengthen the flexibility of conductor itself, and provide sufficient space for the deformation when bending, avoid the conductor and break because of extrusion, the micro air cavity in insulating buffer layer and foamed polypropylene material can absorb stress through compression and spring back when bending, the decompression groove of outer sheath and silicone grease reduce the surface friction and tension when bending, and multiple structures cooperate to make the cable can bear high frequency bending and not easily damaged, greatly prolong the service life.

The invention relates to the technical field of silver-coated copper powder, in particular to silver-coated copper powder with excellent color migration resistance and a preparation method of the silver-coated copper powder. Comprising the steps of copper powder pretreatment, surface coating treatment, chemical silver plating, antioxidant treatment, surface modification and finished product screening. The pretreatment step provides a clean active surface for a plating layer, the silver plating step forms a continuous conductive network, the post-treatment step ensures long-term stability, and the three processes jointly achieve improvement of the color migration resistance.

The invention discloses a silver purification method which comprises the following steps: (1) taking a crude silver plate containing more than or equal to 95% of Ag as an anode and a titanium sheet as a cathode, respectively putting the anodes and the cathodes into an anode chamber and a cathode chamber of a cation diaphragm electrolytic cell, introducing an electrolyte containing nitric acid, silver nitrate and an impurity complexing agent into the anode chamber, introducing an acidic silver nitrate electrolyte into the cathode, the impurity complexing agent is one of ethylene diamine tetraacetic acid disodium salt, 1-hydroxyethylidene-1, 1-diphosphonic acid and diethylene triamine penta (methylene phosphonic acid); (2) electrolysis is started, direct current is introduced, electrolysis is started, high-purity silver is separated out from a cathode, and the purity of the high-purity silver is larger than or equal to 99.99%; compared with other conventional silver electrolysis methods, the method has the advantages that the requirement for impurities of the anode crude silver raw material is lower, the crude silver does not need to be subjected to fire refining pretreatment, and the cost is lower.

The utility model discloses a polythiocyanate silver-plated coating structure of a neodymium-iron-boron workpiece, which comprises a neodymium-iron-boron substrate, and a citrate pre-nickel-plated layer, a nickel-copper alloy coating, a nickel-cobalt alloy coating, a polythiocyanate silver-plated layer and a silver electrolysis protective film which are sequentially prepared on the neodymium-iron-boron substrate from inside to outside. The utility model discloses a polythiocyanate silver-plated coating structure of a neodymium iron boron workpiece, which is characterized in that the binding force of a coating is tested by a thermal shock method according to GB / T 5270-2005 Metal Covering Layer Electro-Deposition and Chemical Deposition Layer Adhesive Strength Test Method on Metal Substrate, and the test result meets the standard requirement; the neutral salt spray test is carried out for 158 hours according to GB / T 10125-2021 Artificial Atmosphere Corrosion Test Salt Spray Test, no corrosives are generated on the surface of a plated part, and a plated layer has good corrosion resistance.

The utility model relates to the technical field of glass ornaments, in particular to a fixing frame adjusting device for a glass ornament silver plating tank, and solves the problems that in the prior art, the fixing frame adjusting device and a fixing frame for bearing materials are inconvenient to adjust up and down, so that the materials are inconvenient to carry out immersion silver plating work at different depths, and the materials are inconvenient to stir; and the silver plating uniformity of the material is influenced. The problems directly cause the problem that the production efficiency is reduced. A fixing frame adjusting device for a glass ornament silver plating tank comprises a frame body, the inner side of the frame body is slidably connected with a bearing plate, the bottom of the bearing plate is fixedly connected with a fixing frame, and the bottom of the inner side of the frame body is fixedly connected with the silver plating tank. According to the utility model, through the up-and-down movement of the fixing frame, not only is the immersion silver plating work of glass materials in different depths in the silver plating tank realized, but also the operation process is greatly simplified, the operation complexity is reduced, the materials are stirred by the carding plate, and the silver plating uniformity is ensured.

The invention discloses cyanide-free silver plating equipment and a cyanide-free silver plating process, relates to the technical field of cyanide-free silver plating, and aims to solve the technical problem that the uniformity of cyanide-free silver plating is difficult to control due to surface geometric structure difference of braided copper wires, and the cyanide-free silver plating equipment comprises a rack, and a plating tank, a wire inlet tank, a wire conveying mechanism, a cleaning tank and a wire adjusting mechanism which are arranged on the rack. A dip angle deflection mechanism is arranged on the inner wall of the plating tank, and variable-taper-angle jet flow mechanisms are symmetrically arranged at the moving end of the dip angle deflection mechanism. The frame bodies are driven by the switching assembly to slide and can be switched between a conical state and an inverted conical state, so that jet flow diverging at a low speed or converging at a high speed is formed, a weaving type is identified, a corresponding jet flow mode is switched, then dip angle deflection is started to enable the jet flow to swing along an arc line, and meanwhile, a moving copper wire is electroplated. According to the method, the jet flow form and the space angle are dynamically adjusted, the problems of uneven flow field coverage and insufficient deep groove permeation caused by different weaving structures are cooperatively solved, high uniformity of a plating layer is achieved, and meanwhile the environment-friendly requirement of cyanide-free silver plating is met.

The utility model discloses a PCB electroless silver board welding ring circuit teardrop structure, and relates to the circuit board production field, the teardrop structure is symmetrically arranged between two adjacent welding rings, the two welding rings are connected through a wire, the teardrop structure is arranged on two sides of the wire, the teardrop structure comprises a wire connecting part and a teardrop part, the wire connecting part is connected with the teardrop part, and the teardrop part is connected with the wire connecting part. The tear dripping parts are arranged at the included angle position of the wire and the welding ring, the two ends of each tear dripping part are connected to the wire and the welding ring respectively, the wire connecting part is arranged on one side of the wire in parallel, the two ends of the wire connecting part are connected to the two tear dripping parts respectively, and the outer surfaces of the wire and the tear dripping structure are coated with anti-corrosion layers. And the circuit copper foil is prevented from being corroded by the galvanic effect in the silver melting production process to generate a thin neck phenomenon.

The invention discloses a preparation method of micro-nano spherical nickel powder and a technological method for directly depositing silver on the surface of the micro-nano spherical nickel powder, and belongs to the field of metal powder preparation technologies and surface treatment. Mixing and stirring the nickel ion solution and the complexing agent solution to obtain a nickel ion complexing system; the method comprises the following steps: adding a certain amount of an auxiliary agent into a nickel ion complexing system, stirring and dissolving to obtain a mixed reaction system of nickel salt, then keeping the temperature of the system constant, slowly adding a reducing agent solution at a constant speed, carrying out a reduction reaction to obtain a nickel particle suspension solution, and then filtering, washing and drying to obtain the micro-nano spherical nickel powder. And carrying out gradient silver deposition reaction on the nickel particle suspension solution after the reaction and the silver plating mixed solution to obtain a suspension solution with silver coated on the surfaces of the nickel particles, and then filtering, washing and drying to obtain the micro-nano spherical nickel powder with silver coated on the micro surface. According to the method, the nucleation and growth process of powder particles can be accurately controlled, the prepared nickel powder is high in sphericity degree, narrow in particle size distribution and clean in surface, a perfect substrate is provided for subsequent high-quality silver plating, island-shaped growth of a silver layer is avoided through the gradient plating technology, and the contact resistance is reduced compared with a traditional technology.

The invention relates to a nitrided part surface silver electroplating process, which belongs to the technical field of electroplating, and specifically comprises the following steps: sequentially carrying out pretreatment, copper pre-plating treatment, nickel pre-plating treatment, silver pre-plating treatment and silver plating treatment on a nitrided part; wherein the copper pre-plating treatment is to deposit a copper plating layer on the surface of the nitriding part so as to cover the nitriding layer. The pretreatment comprises light sand blowing, electrochemical oil removal, weak corrosion and neutralization treatment which are carried out in sequence. After silver plating treatment, passivation / anti-discoloration treatment is carried out. The problem of coating binding force is solved, the high-strength and high-wear-resistance part subjected to nitriding treatment can have excellent high-temperature anti-adhesion performance and higher appearance requirements at the same time, and the application prospects of the part in the high-end fields of aerospace, precise instruments and the like are further expanded.