67 results about "Solderability" patented technology

The invention discloses a printed circuit board manufacturing method for improving the reliability and weldability of a buried copper block, and the method comprises the following steps: processing a depth control blind groove in a PCB core board, and processing a groove hole with a corresponding shape in a prepreg; an embedded copper block is provided, a glue flowing groove is machined in the side wall or / and the bottom of the embedded copper block, and a protective pit is machined in the welding face of the embedded copper block; a frame type carrier is provided, a plurality of positioning grooves which are distributed in an array mode and matched with the copper blocks in shape are formed in the carrier, and the copper blocks with the size smaller than 80 mm * 80 mm are correspondingly placed in the positioning grooves of the carrier to be subjected to browning treatment; laminating the core plate and the prepreg according to a design sequence, embedding the copper block into the blind groove, and ensuring that the welding surface with the protective pit faces upwards; vacuum pressing is conducted, the glue flowing groove is filled with the molten prepreg, part of the molten prepreg flows into the protective pit, and the area, except for the protective pit, of the welding face of the embedded copper block is cleaned; and drilling, copper deposition electroplating and pattern transfer are carried out. According to the manufacturing method of the printed circuit board, the problems that in the prior art, buried copper blocks are poor in combination reliability, and solderability is not guaranteed are solved.

The invention discloses a preparation method of an organic solderable protective film, which comprises the following steps: carrying out controllable micro-etching treatment on the surface of a metal substrate, so that the arithmetic mean roughness of the surface of the metal substrate is less than or equal to 0.20 mu m, and microscopic bulges on the surface of the metal substrate are of smooth hill-shaped structures; and performing preimpregnation treatment and OSP film forming treatment on the surface of the metal substrate in sequence to form the organic weldability protective film. According to the method disclosed by the invention, the uniformity of the organic weldability protective agent film layer and the reliability of high temperature resistance and chemical corrosion resistance are improved by accurately regulating and controlling the microstructure of the copper surface.

The application discloses a rare earth high-strength dual-phase steel and a forming method and application thereof, and belongs to the technical field of dual-phase steel. The forming method of the rare earth high-strength dual-phase steel comprises the following steps: converter smelting, LF refining, RH refining, adding cerium iron and yttrium iron at the end of the RH refining or before continuous casting, continuous casting, three-stage hot rolling, cold rolling and three-stage annealing. The rare earth high-strength dual-phase steel has good cold stamping formability, high weldability, no rare earth element segregation, no cracking of steel forming, high yield, and can be directly used to prepare automobile bodies after cold stamping forming at normal temperature. There is no rare earth inclusion or coarse carbon nitride brittle bulk agglomerate on the surface layer of the weld, the rare earth element is in a dispersed distribution state, has excellent dispersion strengthening effect, the weld is not prone to cracking, and the mechanical properties of the weld are superior to those of the base material.

The application discloses an aluminum nitride film circuit substrate and a preparation method thereof, and relates to the technical field of aluminum nitride substrates.The application is characterized by the following steps: a titanium film is plated on the surface of an aluminum nitride ceramic substrate by magnetron sputtering, and then a copper film is plated on the surface of the titanium film by magnetron sputtering; and a nickel film is plated on the surface of the copper film by a chemical plating method to prepare the aluminum nitride film circuit substrate.Through the titanium-copper gradient dynamic transition technology, a gradient alloy layer is formed to reduce the interface stress; the titanium and the surface of the aluminum nitride are combined through a chemical bond to form a dense transition layer, thereby relieving the difference in the thermal expansion coefficient; the copper enhances the conductive performance of the surface of the aluminum nitride ceramic substrate; the titanium compensates for the interface defects of the mismatch between the copper and the aluminum nitride ceramic lattice; the chemical nickel plating enhances the hardness and corrosion resistance of the aluminum nitride ceramic substrate, and the aluminum nitride film substrate is endowed with weldability and bondability.

This invention discloses a conductive paste for metallization of electronic ceramics, belonging to the field of electronic materials technology. The conductive paste for metallization of electronic ceramics of this invention includes copper alloy powder, glass powder, and an organic carrier. By controlling the ratio of copper, aluminum, and zinc in the copper alloy, the thermal expansion coefficient of the alloy is adjusted, making it compatible with electronic ceramic substrates such as alumina ceramics and zinc oxide varistors, achieving metallization through sintering under air conditions. The addition of tin improves the solderability of the metallized layer, meeting the process requirements of electronic components. The glass powder added in this invention has a low initial melting temperature, high bonding strength with the copper alloy, and strong adhesion to the ceramic substrate; combined with a specific ratio of organic carrier, it effectively improves the conductivity of the metallized layer after sintering.

The application discloses a semiconductor device solderability test device and a test method, which comprises an experimental box body, an experimental table is arranged in the experimental box body, a solder furnace and a flux furnace are arranged at the top end of the experimental table, and a lifting and rotating mechanism is arranged at the bottom end of the experimental table; an experimental clamp is arranged, a scale column is arranged at the top end of the experimental clamp, the scale column is attracted to the top end of the experimental clamp through an electromagnet, a weighing mechanism is connected to the top end of the scale column, and proximity switches corresponding to the solder furnace are arranged on the two sides of the experimental clamp; wherein a cleaning mechanism is arranged at the top end in the experimental box body. The weighing reading of the weighing mechanism is prevented from changing due to collision, and the accuracy of experimental results is affected; meanwhile, the depth of the semiconductor device immersed in the solder can be observed through the scale column, the lifting height of the solder furnace is adjusted, and the depth of the semiconductor device immersed in the solder is facilitated to be controlled in the experiment.

There is provided a bonding wire for semiconductor devices that exhibits a favorable bondability even when being applied to wedge bonding at the room temperature, and also achieves an excellent bond reliability. The bonding wire includes a core material of Cu or Cu alloy (hereinafter referred to as a “Cu core material”), and a coating containing a noble metal formed on a surface of the Cu core material. A concentration of Cu at a surface of the wire is 30 to 80 at %.

The invention belongs to the technical field of metal material surface treatment, and discloses a production process of a weldable electroplated chromium plate. According to the process, cluster-shaped peak morphology is transferred on the surface of a cold-rolled steel coil through a laser texturing roller, and staged double-layer chromium electroplating is combined, specifically, a discontinuous chromium layer is formed on the top of a micro convex peak through first-time high-current pulse electroplating, and local iron leakage points are reserved; the second low current direct current plating covers an ultrathin continuous chromium film to maintain macro passivation. According to the invention, a composite functional structure with both macroscopic passivation integrity and microcosmic conductive selectivity is constructed on the surface of chromium-plated iron by accurately controlling the microstructure of the surface of a base material and double-layer chromium plating process parameters, so that the technical bottleneck of the chromium-plated plate in resistance welding application is effectively solved, collaborative optimization of weldability and corrosion resistance is realized, and the application range of the chromium-plated plate in resistance welding is widened. And a reliable technical path is provided for comprehensive replacement of chromium-plated iron in the field of metal packaging.

The utility model relates to the technical field of photovoltaic power generation, in particular to a solar cell and a photovoltaic assembly, and aims to solve the problem that a secondary grid welding area of the conventional solar cell is easy to cause welding grid breakage. Therefore, the solar cell comprises an auxiliary grid line and an auxiliary grid welding area, the auxiliary grid line is printed by adopting first metal slurry, the auxiliary grid welding area is printed by adopting second metal slurry, and the welding tension of the second metal slurry is greater than that of the first metal slurry. According to the utility model, the auxiliary grid lines and the auxiliary grid welding areas on the solar cell are printed through two different metal pastes, and the welding tension of the second metal paste used for printing the auxiliary grid welding areas is greater than that of the first metal paste used for printing the auxiliary grid lines, namely, the welding tension of the second metal paste is greater than that of the first metal paste used for printing the auxiliary grid lines. The weldability of the second metal slurry is better than the weldability of the first metal slurry, so that the welding quality of the auxiliary grid welding area can be improved, the probability of welding broken grids can be effectively reduced, and the situation of welding broken grids is avoided.

The invention discloses a fixture for electronic device solderability test, which is used for being detachably connected with solderability test equipment, the solderability test equipment comprises a working table, and the working table is provided with a solder groove capable of lifting and moving. The base is detachably connected with the working table top, the support is connected with the base in a sliding mode and can move back and forth along the base, the clamping mechanism is connected with the support through a universal connecting assembly, the clamping mechanism is used for clamping a to-be-tested device, and the position of the clamping mechanism can correspond to that of the welding flux groove. The clamping mechanism comprises a clamping space used for clamping the device and a clamping adjusting mechanism used for adjusting the size of the clamping space and clamping the device, a test is completed through the clamp, the device is directly held by hand instead of manual work, safety accidents caused by handheld operation are avoided, the size of the clamping space can be adjusted, and the device is convenient to use. And more devices with different sizes and different shapes can be clamped, and the universality is higher.

The invention relates to the technical field of metal material welding, in particular to a low-deformation high-fatigue-performance welding method for a high-strength 6-series thin-wall aluminum alloy, which comprises the following steps: S1, precision pretreatment before welding: carrying out surface cleaning and weldability protection on a groove and an adjacent area of a to-be-welded workpiece; s2, low-heat-damage double-source collaborative welding is conducted, specifically, welding is conducted through double-wire pulse consumable electrode inert gas shielded welding, and welding-following local chilling is conducted on the back face of a welding seam in the welding process; and S3, after-welding active performance regulation and control treatment is conducted, specifically, high-frequency mechanical shock treatment is conducted on the weld toe area of the weld joint cooled to the room temperature, and then local solid solution and aging composite heat treatment is conducted on the area containing the weld joint and the heat affected zone. According to the method, the welding stability is guaranteed through pretreatment, the total heat input is reduced through double-wire welding, a high-temperature area is shrunk along with welding chilling, cooperative control over welding deformation and residual stress is achieved, pressure stress is introduced through weld toe impact, a softening area is repaired through local heat treatment, and the fatigue performance of a connector is improved.

The invention relates to a manufacturing method of a selective chemical nickel ceramic-based printed circuit board for a power module, and aims to solve the technical problems that a chemical nickel layer is easy to yellow and a copper surface is easy to oxidize in a subsequent process in the prior art. The method comprises the following steps: pasting a protective film and performing laser windowing on a ceramic-based copper-clad plate with a manufactured circuit for the first time, exposing an area needing chemical nickel plating, and performing chemical nickel plating; after the film is torn off, the second time of protection film pasting and laser windowing are carried out, the copper surface area needing to be treated is accurately exposed, and meanwhile the plated nickel layer is tightly covered with the protection film; and finally, carrying out anti-oxidation treatment on the exposed copper surface. The core of the invention lies in a collaborative process of two-time film pasting and laser windowing, and a film is pasted again after chemical nickel plating to protect a nickel layer, so that the nickel layer is completely isolated from acid and alkali liquid medicine in the subsequent copper surface treatment, the yellowing phenomenon of the nickel layer is fundamentally avoided, and the cleanness and weldability of the copper surface are ensured.

The invention provides conductive silver paste special for a glass-based circuit board and a preparation method of the conductive silver paste. The conductive silver paste comprises, by weight, 60-90 parts of silver powder, 4-30 parts of polymer resin, 1.5-5 parts of inorganic filler, 0.05-0.5 part of auxiliaries and 5-20 parts of solvent. The silver powder is spherical and nano silver powder; the glass powder is lead-free glass powder, and the inorganic additive filler is glass powder, indium-tin alloy powder and an expansion coefficient adjusting material (nickel sulfide); the special conductive silver paste for the glass-based circuit board, provided by the invention, has the characteristics of easiness in printing, good solderability by using a lead-free solder after sintering, long service life of a finished product, high and low temperature climate resistance, acid, alkali and salt chemical corrosion resistance, and firm adhesion with a glass substrate without falling after long-term use.

This invention relates to the field of intelligent manufacturing technology and provides a deep learning-based adaptive optimization method for welding process parameters. The method includes: acquiring the weld path and quality target of the parts to be welded; dividing the weld path into a set of weld segment units; collecting pre-welding geometric data and in-welding process data for each weld segment unit to obtain segment welding state characteristics; constructing a local weldability risk field to obtain segment risk field results; generating a segment parameter candidate set based on the welding parameter safety working window as a constraint and the segment risk field results; inputting the segment welding state characteristics, segment risk field results, and segment parameter candidate set into a pre-constructed physical constraint deep learning model to obtain segment quality prediction results; and performing rolling parameter optimization based on the segment quality prediction results to obtain a segment welding parameter sequence and sending it to the welding execution end.

The invention provides a simulation test method based on a non-collapse solder ball BGA device weldability test, and relates to the technical field of BGA device welding, and the method comprises the following steps: S1, solder ball water vapor aging; s2, solder ball drying: performing high-temperature baking in a dry environment; s3, solder paste is applied to the solder ball to prepare a sample, and reflow soldering is conducted on the prepared sample; a proper amount of soldering paste consistent in shape is directly printed on the non-collapse solder ball BGA solder ball through a soldering paste applying tool, and the soldering paste at least covers 50% of the surface of the solder ball; according to the invention, the whole preparation process is more convenient, and the problem of solderability test failure caused by solder ball adhesion and the like cannot be formed, so that the sample preparation efficiency and the solderability test success rate are improved, and the cost increased by preparing samples in multiple tests is also reduced; therefore, the success rate and the efficiency of the weldability test of the non-collapse solder ball BGA device are improved.

The present application belongs to the technical field of aluminum alloy welding wire, and relates to an in-situ nano-particle reinforced welding wire for aluminum body welding and a welding method thereof. The welding wire is prepared into a stir head and embedded into a friction stir welding device; the welding wire and a welding piece are connected with "+" and "-" poles of an electric welding machine respectively to form an arc welding. Through the combination of the friction stir welding and the arc welding, in-situ reaction of the welding wire is promoted, and binary in-situ nano-particles are generated through doping and reaction of mixed salt, rare earth and alloy elements. This method can not only ensure the weldability of the welding wire and the welding piece, but also strengthen and improve the mechanical properties and microstructure of the weld through the binary in-situ nano-particles. The in-situ reaction of the reaction salt and Al has no by-product, in addition, the in-situ reaction is beneficial to the enhancement of the wettability of the endogenous particles and the base material, the addition of the rare earth can also play an obvious grain refinement role, and can overcome the problems of serious crack tendency, alloy element burning loss, coarse structure grain, serious joint performance decline and the like.

The application provides a flexible printed circuit board prepared based on a weldable silver paste and a preparation method, and relates to the technical field of flexible printed circuit boards.The flexible printed circuit board comprises a substrate shielding composite layer, a weldable silver paste layer is arranged on the substrate shielding composite layer, a protective layer is arranged on the weldable silver paste layer, a pad area and a non-pad area are divided on the protective layer, the pad area forms a weak curing structure after light-heat synchronous curing, and the pad area is exposed after weak alkali treatment, and the non-pad area forms a complete curing structure;the weldable silver paste system is used to improve the line conductivity, the silver surface is directly exposed, the weak alkali treatment breaks through the weldability bottleneck of a traditional metal plating layer, the screen printing process is used to replace multi-step plating, and the production process is greatly simplified.Compared with an aluminum plating process, a copper plating process and a gold plating process, the application has significant advantages in conductivity, weldability and process simplification.

The invention discloses a weldability test method for simulating a BGA surface welding process. The method comprises the following steps: S01, performing water vapor aging and drying on a BGA sample; s02, basket type screens of various specifications are manufactured; s03, basket type net plates of the corresponding specifications are placed on the bearing plate; s04, printing the soldering paste on the basket type screen until each mesh is filled with the soldering paste, and removing the soldering paste on the upper surface of the basket type screen; s05, removing the basket type screen plate, checking the solder paste array pattern on the bearing plate, repeating S03 to S05 if the solder paste array pattern is stained, and otherwise, turning to S06; s06, aligning each solder ball and the solder paste array pattern of the sample subjected to water vapor absorption aging and drying, integrally moving the sample, the solder paste and the bearing plate into a reflow furnace, and heating according to a preset reflow soldering condition; s07, after simulation reflow soldering is completed, the sample, the soldering paste and the bearing plate are moved out and cooled to the room temperature, and the samples with the solder balls infiltrated by the soldering paste to different degrees are peeled off; and S08, cleaning impurities on the surfaces of the sample, the basket type screen plate and the bearing plate, and checking the infiltration and adhesion conditions of the solder balls.

The invention discloses a plating layer structure for inhibiting growth of tin plating layer whiskers and a preparation method of the plating layer structure, and belongs to the technical field of metal plating. The plating layer structure comprises a substrate, a nickel middle layer and a tin-bismuth alloy plating layer are sequentially arranged on the substrate, the thickness of the nickel middle layer is 0.3-1 micron, the thickness of the tin-bismuth alloy plating layer is 3-10 microns, and the mass fraction of bismuth in the tin-bismuth alloy plating layer is 1 wt.%-5 wt.%. According to the method, diffusion of substrate metal atoms is blocked through the nickel intermediate layer, the growth probability of tin whiskers is remarkably reduced by combining the inhibition effect of bismuth elements in the tin-bismuth alloy on tin grain growth, meanwhile, the sulfuric acid system electroplating process is low in cost and good in stability, and the plating layer has excellent weldability and binding force; the method is suitable for electronic component pads and other scenes with high reliability requirements, and the technical problem that a traditional tin plating layer is prone to generating whiskers to cause short circuit of electronic equipment is solved.

The application discloses a method for electroless nickel-palladium-gold plating on an alumina high-temperature co-fired ceramic substrate, and belongs to the technical field of electroless nickel-palladium-gold plating. The method comprises the following steps: hanging, oil removal, micro-etching, glass micro-etching, acid pickling, palladium activation, inhibition, electroless nickel-boron plating, pre-plating of palladium, electroless palladium plating and electroless gold plating. The method is used for electroless nickel-palladium-gold plating on an alumina high-temperature ceramic tungsten metal to modify the metal, so that the workpiece has good weldability and bondability, the gold wire bonding strength can reach 280 mN, the average gold ribbon bonding tension is greater than 500 mN, and the average chip shear strength reaches 5.11 Kgf, all of which reach the relevant technical standards of the national military standard.

This invention discloses a slurry for welding surfaces of ceramic dielectric filters and its preparation method. The slurry comprises, by weight, 65-90 parts silver powder, 0.5-3 parts glass powder, 0.5-3 parts inorganic additives, 3-15 parts organic carrier, and 3-15 parts solvent. The silver powder comprises, by weight, 10-50 parts spherical silver powder, 5-40 parts flake silver powder, and 10-50 parts microcrystalline silver powder. And / or the glass powder comprises, by weight, 30-70 parts bismuth oxide, 10-40 parts copper oxide, 5-20 parts boron oxide, 1-15 parts manganese oxide, 0.1-15 parts silicon oxide, 0.1-5 parts aluminum oxide, 0.1-3 parts calcium oxide, 0.1-3 parts sodium oxide, and 0.1-3 parts lithium oxide. This invention introduces flake silver powder or microcrystalline silver powder to reduce the density of the silver layer, thereby improving the silver etching phenomenon during the soldering of the filter functional surface to the PCB, effectively enhancing solderability and improving the adhesion of the paste; or introduces Bi-Cu-B-Mn glass powder to improve the solderability of the paste and improve its adhesion.

The utility model relates to the technical field of composite materials, and discloses a multi-application-scene aluminum-based composite copper aluminum foil which comprises an aluminum base body, high-frequency shielding layers attached to the two sides of the aluminum base body through the magnetron sputtering plating technology, and flexible extension layers attached to the two opposite sides of the two sets of high-frequency shielding layers through the magnetron sputtering plating technology. Thermal expansion matching layers are attached to the sides, opposite to the high-frequency shielding layer, of the two groups of flexible extension layers through a magnetron sputtering plating process; through the cooperation of the flexible extension layer, the thermal expansion matching layer, the high-conductivity copper layer, the weldability plating layer, the grain boundary strengthening layer and the gradient Cu-Cr-CrN layer, the problem that a copper-aluminum interface is fractured when the LED light bar plate is curled and bent is solved, the problem of deformation layering caused by the difference of thermal expansion coefficients of the copper-aluminum layer is solved, the thermal expansion synchronism of the copper-aluminum layer is guaranteed, and the service life of the LED light bar plate is prolonged. And the bending resistance and the shielding effectiveness of the aluminum-based composite copper-aluminum foil as well as the peel strength of a copper-aluminum bonding interface are improved.

The application discloses a kind of composite solder ball, preparation method and stacked package structure, comprising: composite core, by continuous phase matrix and strengthening phase are constituted, the strengthening phase accounts for 15%~30% of the total volume of core, the compression modulus of the composite core is ≥3GPa and thermal expansion coefficient is ≤55ppm / ℃;Metal transition layer, is coated in the polymer core;Tin silver alloy outer layer covering the metal transition layer.Composite core is constituted by continuous phase polymer matrix and strengthening phase fiber network, realizes high-temperature pressure resistance and low thermal expansion characteristics by specific volume ratio and mass ratio, maintains solid rigid characteristics in welding high temperature interval, directly bears mechanical load, completely eliminates the risk of interlayer height collapse, metal transition layer forms and the mechanical interlocking combination interface of core, tin silver alloy outer layer provides weldability and electrical connection function, realizes that composite solder ball can play the role of support and also can play the role of welding dual-functional technology fusion.

The invention belongs to the technical field of electroplating, and particularly relates to a magnesium-aluminum alloy nickel plating material and a preparation method thereof. The preparation method of the magnesium-aluminum alloy nickel plating material comprises the following steps: (1) pretreatment; (2) oil removal: the pretreated magnesium-aluminum alloy is subjected to oil removal; (3) first alkaline etching; (4) acid etching; (5) descaling for the first time; (6) secondary alkaline etching; (7) descaling for the second time; (8) zinc deposition; (9) alkaline chemical nickel plating; (10) carrying out acidic chemical nickel plating; (11) recycling; (12) secondary cleaning; and (13) drying is conducted, specifically, the magnesium-aluminum alloy is dried, and the magnesium-aluminum alloy nickel-plated material is obtained. The magnesium-aluminum alloy nickel plating material prepared through the method is high in plating layer binding force, excellent in weldability and high in heat resistance, impact resistance and salt spray resistance.

The invention discloses high-weldability aluminum-silicon coating steel containing residual element Cu for electric furnace steelmaking and a preparation method of the high-weldability aluminum-silicon coating steel, and belongs to the technical field of metal materials. Based on the innovative thought of copper alloying, the residual element Cu in waste steel is refined, the content of alloying elements Cu in the aluminum-silicon coating steel and the component content of As, Sn, Sb and Bi are precisely regulated and controlled, and the high-weldability aluminum-silicon coating steel containing the residual element Cu is obtained; the invention aims to develop the high-weldability aluminum-silicon coating steel. At present, in the prior art, a certain content of ferrite exists in the microstructure of an aluminum-silicon coating steel welding joint prepared without removing a coating, however, according to the invention, steel components are innovatively designed, and after a residual element Cu is added, the aluminum-silicon coating steel welding joint is subjected to full martensization, so that the mechanical property of the aluminum-silicon coating steel welding joint is remarkably improved. The method disclosed by the invention inherits the concept of sustainable development, realizes recycling of waste steel, and has important significance on development of novel aluminum-silicon coating steel and popularization and application of the novel aluminum-silicon coating steel in the field of laser welding.

This invention discloses a thin-film capacitor, including a housing, a capacitor core, and an electrode assembly. The electrode assembly includes an external electrode and an internal electrode, with the internal electrode integrating solder pins. When the internal electrode is made of low-cost non-pure copper materials such as aluminum, aluminum alloy, or steel, the solder pins are partially coated to ensure the solderability of the electrode and the core, and to ensure reliable connection. When the external electrode is entirely made of low-cost non-pure copper materials such as aluminum, aluminum alloy, or steel, the exposed terminals are also coated to ensure the conductivity of the non-copper electrodes and the terminals, and to reduce contact resistance.

The application discloses a production process optimization method and system for a photovoltaic module, and relates to the technical field of photovoltaic production. The method comprises the following steps: front welding is performed on a target photovoltaic module, an infrared thermal image is used to monitor the thermal distribution of a welding head and a welding seam area, and a welding seam peak temperature distribution is obtained by analysis; the weldability of a plurality of tail ends after front welding is identified according to a preset index, and a tail end weldability distribution is obtained; based on the welding seam peak temperature distribution and the tail end weldability distribution, back stringing is positioned, compensated and matched with a secondary reflow heat curve, and a back stringing process optimization scheme is formed; and the back stringing is completed according to the scheme. The technical problems of unstable back stringing quality and electrical performance loss caused by the mismatch of front welding and back stringing process parameters are solved, the technical effect of realizing accurate positioning and heat process matching of back stringing through the data linkage of welding heat distribution and tail end weldability is achieved, and the stringing quality and the component yield are improved.

The invention discloses a trepanning shaft well type hanging tool and an assembling method thereof, and belongs to the field of heat treatment process technologies and tools. The tool comprises a hanging part (a hanging ring and a hanging seat), a connecting part (a double-layer hanging rod, a transverse pin and a plug pin) and a shaft hanging frame (a radial plate seat, a hanging frame plate and a pin). The upper portion of the double-layer hanging rod is connected with the hanging seat through a transverse pin, the lower portion of the double-layer hanging rod is connected with the wheel disk seat through a plug pin, and hanging frame plates on the two sides of the wheel disk seat are fixed to the perforated shaft through pins. The assembling method comprises the steps of tool manufacturing, assembling, shaft part installing and tool placing. According to the scheme, shaft workpiece hanging can be achieved without welding, the welding crack risk is avoided, and the method is suitable for shaft parts poor in weldability and capable of being welded; the shaft workpiece is suspended, and heat treatment distortion is reduced; the tool is stable in structure, easy and convenient to operate, labor-saving, capable of improving production efficiency and workpiece quality and suitable for shaft part heat treatment hanging scenes.

The invention discloses a protective coating for the surface of an electronic component and a preparation method thereof, and relates to the technical field of coatings. The coating is prepared from the following raw materials in parts by mass: 100 parts of epoxy modified acrylate copolymer, 8 to 9 parts of butyl acetate, 6 to 7 parts of propylene glycol methyl ether acetate, 6 to 7 parts of isododecane, 4 to 6 parts of modified boron nitride nanotube, 3 to 5 parts of synergist, 0.2 to 0.4 part of 2-methylimidazole, 0.1 to 0.3 part of defoaming agent, 0.2 to 0.4 part of flatting agent and 0.1 to 0.3 part of sterilizing agent. The epoxy modified acrylate copolymer, the modified boron nitride nanotube, the synergist and other components are introduced, so that the adhesive force, impact resistance, wear resistance, weather resistance, aging resistance, dielectric strength, volume resistivity and high-frequency signal adaptability of the protective coating are effectively improved while the weldability of a lead of an electronic component is not affected. Therefore, the method has a wider application prospect.