965 results about "Solder material" patented technology

The invention discloses an intelligent welding forming method and system for a green building steel heating radiator, and the method comprises the following steps: carrying out the surface defect recognition of a steel heating radiator base material based on an AI visual inspection system, recognizing a qualified base material, and automatically matching the type of a welding material from a material database according to the material and thickness parameters of the qualified base material. Welding parameters are intelligently matched through AI visual inspection and a neural network model, a laser and friction stir hybrid welding process is combined, traditional manual operation is replaced, the welding efficiency and precision are improved, and the problems of uneven welding seams and the like are solved; welding data are analyzed in real time through a multi-mode AI model, parameters are dynamically adjusted, intelligent defect recognition and repair welding are achieved in cooperation with 3D visual inspection, and the quality stability is improved through whole-process monitoring; smoke dust is treated through an environment-friendly process, acid pickling is replaced with mechanical rust removal, efficient recycling of materials is achieved through waste recycling, a green manufacturing system is constructed, and the sustainable development requirement of green buildings is met.

The invention discloses a welding material, a welding material, application and a preparation method, and the welding material comprises the following raw materials by weight percent: 1%-3% of Si, 1.2%-3.2% of Mg, 1%-3.6% of Zn, 0.6%-1.6% of Cu, 0.5%-0.8% of Mn, 0.2%-0.45% of Cr, 0.1%-0.25% of Ti, 0.05%-0.1% of Zr, 0.05%-0.1% of Sc, and the balance of Fe. 0.2%, and the balance being Al and inevitable impurities. By regulating and controlling the contents of Zn, Cu, Mg and Si elements, the precipitation enthalpy of a nanoscale strengthening phase is reduced, so that the bake hardening effect of a welding seam is improved, and the problem that the welding seam is excessively softened due to melting of the nanoscale precipitation phase is solved. In addition, the Fe-containing brittle phase characteristic in the weld joint is improved by adding Mn and Cr elements, and the hot crack tendency of the weld joint is reduced by combining Zr, Sc, Ti and other grain refinement elements, so that the strength and toughness of the weld joint are further improved.

The invention belongs to the field of metal material processing, and particularly relates to a nuclear power nickel base alloy welding wire and a preparation method thereof.The nuclear power nickel base alloy welding wire comprises, by weight, 0.01%-0.05% of C, 0.10%-0.30% of Si, 28.5%-30.5% of Cr, 7.0%-11.0% of Fe, smaller than or equal to 0.10% of Co, 0.50%-1.00% of W, 3.0%-4.0% of Mo, 0.005%-0.010% of B, 0.1%-0.3% of Al, 0.1%-0.2% of Ti, 0.005%-0.020% of Zr, 2.0%-2.5% of Nb, 0.1%-0.5% of Ta, 0.20%-0.30% of RE, smaller than 0.005% of S, smaller than 0.005% of P, 2.0%-4.0% of nano ceramic materials and the balance Ni, the nickel-based alloy welding material is prepared through the steps of smelting, high-low temperature refining, annealing, forging, rolling, multi-pass drawing, annealing, solid solution-aging treatment, acid pickling, coating and plating, and the problems that in the prior art, when used for welding, a nickel-based alloy welding material is prone to cracks, and the strength is low due to hot corrosion can be effectively solved.

The invention provides multi-element alloy silver-free copper-based brazing filler metal and a preparation method thereof.The brazing filler metal comprises, by mass, 30%-40% of zinc, 4%-11% of manganese, 1%-4% of tin, 0.2%-0.6% of silicon, 0.2%-1% of rare earth elements and the balance copper, the rare earth elements comprise cerium, praseodymium and rhenium, and the mass ratio of cerium to praseodymium to rhenium is (0.8-1.2): (0.8-1.2): (0.6-1.0). According to the multi-element alloy silver-free copper-based brazing filler metal, the performance of a brazed joint is improved, the strength, toughness, fatigue resistance and the like of the joint are improved, and the reliability and stability of connection under various working conditions are ensured.

The invention discloses a high-strength steel welding rod for 1000 MPa water and electricity and a preparation method and application of the high-strength steel welding rod. The invention belongs to the technical field of welding materials. The technical problems that the low-temperature impact toughness of an existing welding material for 1000 MPa-grade high-strength steel needs to be improved, and the welding cold crack sensitive index is too large are solved. The welding rod is composed of a core wire and a coating wrapping the surface of the core wire. Powder of the coating is formed by mixing marble, fluorite, rutile, silica powder, electrolytic manganese, ferrosilicon, graphite, ferromolybdenum, chromium metal, iron powder, nickel powder, sodium carbonate and sodium alginate. The welding rod has the advantages of good all-position welding process performance, stable electric arc, small flying speed, uniform coating melting, beautiful weld joint forming and good operability of welders. And weld metal has good mechanical properties. And the method is used for welding the high-strength steel for the 1000MPa-grade water

The utility model discloses a marine lean leveling tool for segmented welding. The marine lean leveling tool comprises a flat-bulb steel leveling device, a T-shaped profile leveling device and an angle steel leveling device, the three devices are optimized, so that the use is more convenient, the original limitation is overcome, and the requirements of an actual production field are met; the three devices achieve leveling and butt joint of steel plates such as flat-bulb steel, T-shaped profiles and angle steel on a ship body, plate stacking and folding are omitted, steel structures in the steel plates are not damaged, base metal is protected, operation is easy, a large number of welding materials and polishing working hours are saved, working efficiency is improved, and the working environment of workers is improved; the tool is long in service life and convenient to disassemble and maintain, the work efficiency is improved, the hull structure is effectively protected, and all leveling work can be completed through single-person operation.

To provide a technique that can determine whether a gap has occurred between materials to be welded and whether welding is defective.SOLUTION: An estimating method for a nugget diameter of materials welded by spot welding includes: an expansion amount calculating step of calculating expansion amounts of the welded materials being energized, using amounts of displacement and amounts of applied voltages in an electrode; an inclination calculating step of dividing a characteristic line showing a temporal change having the expansion amounts set as a vertical axis and time set as a lateral axis into a plurality of time sections, and calculating respective inclinations of the characteristic line in the plurality of time sections; a discriminating step of discriminating whether spot welding is defective or not, when a minimum expansion amount of the calculated expansion amounts is below or equal to a predetermined threshold, using a discriminant created from historic data showing a temporal change of expansion amounts in spot welding performed in the past including the inclination in an input variable; and an estimating step of estimating a nugget diameter by correcting the expansion amounts, when it is discriminated that the spot welding is not defective.SELECTED DRAWING: Figure 2

The invention belongs to the technical field of welding materials, and relates to a welding wire for aluminum-based or aluminum-silicon-based coating hot stamping steel and a preparation and use method of the welding wire. The welding wire for the aluminum-based or aluminum-silicon-based coating hot stamping steel is composed of the following chemical components of, by weight, 0.12%-0.28% of C, 0.6%-1.2% of Si, 1.9%-2.7% of Mn, 0.4%-2.0% of Cr, 0.5%-1.0% of Mo, 1.6%-3.5% of Ni, 0.05%-0.1% of Zr + Ti + Nb, 0%-0.02% of RE, smaller than or equal to 0.010% of P and the balance Fe and inevitable impurities. The welding wire can prevent a welding seam from forming high-temperature delta ferrite, and meanwhile complete austenitizing of the welding seam during hot stamping is achieved by precisely regulating and controlling the content of the elements. The invention further provides a preparation method and a use method of the welding wire for the aluminum-based or aluminum-silicon-based coating hot stamping steel.

The invention discloses a high-entropy alloy system high-temperature brazing filler metal and a preparation method and application thereof, and relates to the technical field of welding materials.The preparation method comprises the following steps that iron powder, cobalt powder, nickel powder, copper powder and molybdenum powder are weighed and evenly mixed, and mixed metal powder is obtained; the mixed metal powder is put into a first ball milling tank, argon is introduced, ball milling is conducted for at least 15 h, and alloyed powder is obtained; the alloyed powder is put into a mold and sintered in the hydrogen atmosphere at the temperature of 1000-1200 DEG C, and a sintered blank is obtained; the sintered briquette is crushed into particles, the particles are put into a second ball milling tank, ball milling is conducted for at least 20 h in the argon atmosphere, and high-entropy alloy powder is obtained; and weighing the high-entropy alloy powder, borax and polyvinyl alcohol, and uniformly mixing to obtain the high-entropy alloy system high-temperature brazing filler metal. The prepared high-entropy alloy system high-temperature brazing filler metal has the advantages of being good in component uniformity, high in performance stability and excellent in wettability and filling performance, and the welding quality of a brazed joint can be effectively guaranteed.

The invention relates to the technical field of welding materials, in particular to a high-efficiency deposited nickel-based welding wire capable of preventing welding cracks based on phase regulation and application of the high-efficiency deposited nickel-based welding wire, and the nickel-based welding wire comprises the following chemical components in percentage by weight: less than or equal to 0.03% of C, 0.10-0.20% of Si, 2.9-3.2% of Mn, and 1t of P; 0.005%, S: lt; 0.003% of Cu, 19.7-20.5% of Cr, less than or equal to 0.04% of Co, and 1t of Cu; the Ni-based alloy comprises the following components in percentage by weight: 0.10% of Ni, 0.3-0.6% of Ti, 0.4-2.0% of Fe, 2.1-2.9% of Nb, less than or equal to 0.3% of Mo, less than or equal to 0.01% of N, less than or equal to 0.005% of O, less than or equal to 0.50% of other impurity elements and the balance of Ni. The specific value of Ti to Nb is controlled to be 0.10-0.22, the specific value of C to Nb + Ti is controlled to be 0.012 or below, appropriate morphology and distribution of (Nb, Ti) C type intergranular precipitates are obtained, precipitation of grain boundary M23C6 is reduced, and the creep resistance and high-temperature deplasticity crack resistance of the material are effectively optimized.

A method of manufacturing a chip structure is provided. The method includes attaching a chip to a chip carrier using a chip attachment layer, where the chip attachment layer includes a metal having a first melting point, where the chip includes a solder layer, and the chip carrier includes a further solder layer, where the solder layer includes a metal having a second melting point. The solder layer and / or the further solder layer comprises a respective solder material having a second melting point lower than the first melting point; and forming an intermetallic phase between the solder material and the metal of the die attach layer by melting the solder material having the second melting point.

The invention discloses a halogen-free low-splashing environment-friendly solder wire and a preparation method thereof, and relates to the technical field of electronic welding materials, and the halogen-free low-splashing environment-friendly solder wire is prepared from the following raw materials in percentage by mass: 1-4wt% of halogen-free scaling powder and the balance of lead-free solder; the lead-free solder is composed of the following components of Cu, Bi, Al, Ga, Ir, Ca, In and Sn. The halogen-free scaling powder comprises the following components: (3, 6-diamino acridine-9-yl) boric acid, glycerol triabietate, 3-(N-morpholinyl)-2-hydroxy propanesulfonic acid sodium salt, 3-trihydroxymethyl methylamino-2-hydroxy propanesulfonic acid, hexahydro-1, 3-ethoxy-s-triazine, a functional copolymer, a surface active agent, a corrosion inhibitor, a halogen-free activity reinforcing agent, an antioxidant, a solvent and rosin resin. The solder wire is low in splashing rate, high in surface resistivity and welding spot reliability, free of obvious corrosivity and good in weldability.

A connector configured to connect densely disposed cables to a board. The connector may include two or more rows of terminals held by a housing such that the two or more rows of terminals are at a same height with respect to a board that the connector would be mounted to. Such a configuration enables the connector to fit into a space limited by, for example, another component mounted to the board. The terminals may include first contact portions configured to be mounted onto a surface of the board when pressure is applied to the terminals so as to avoid the use of materials that may cause undesired shorting such as soldering materials. The terminals may include second contact portions configured to receive the cables. The second contact portions of ground terminals of a same row may be connected by a strip configured to contact shields of cables attached to the row.

The invention discloses a low-temperature high-toughness austenitic stainless steel welding wire and a preparation method thereof, and relates to the technical field of welding materials, in particular to a welding wire with high-toughness mechanical properties of formed cladding metal in a low-temperature environment and a preparation method of the welding wire. The Ti element is introduced into the welding wire, the dosage relation of the Al element and the Ti element is controlled, and the mass ratio of Al to Ti is kept to be (5-10): 1; a proper amount of Al element can play a role in purifying a molten pool during welding work, a proper amount of Ti element can effectively stabilize an austenite phase, and therefore it is guaranteed that the welding wire has the basic welding capacity, and meanwhile after the welding wire is converted into cladding metal, the welding wire is not prone to deformation. The material characteristics and the like of the material can meet the use requirements at room temperature and ultralow temperature environment, that is, the material has and keeps good tensile property, impact property and the like, so that pipelines, containers and the like prepared from the material can be used for transmitting or loading special low-temperature materials such as liquid hydrogen, liquid helium and the like.

A wave soldering machine is configured to perform a wave soldering operation on a printed circuit board. The wave soldering machine includes a housing and a conveyor coupled to the housing. The conveyor is configured to deliver a printed circuit board through the housing. The wave soldering machine further includes a wave soldering station coupled to the housing. The wave soldering station includes a solder pot having a reservoir of solder material, a flow duct positioned in the reservoir of the solder pot, and a wave soldering nozzle assembly coupled to the flow duct. The wave soldering nozzle assembly has a solder distribution baffle configured to create a solder wave. The wave soldering nozzle assembly is configured to control a width of the solder wave through the solder distribution baffle to produce a maximum width solder wave and a minimum width solder wave.

The invention discloses an austenitic stainless steel welding wire for a liquid hydrogen storage tank and a preparation method and application of the austenitic stainless steel welding wire, and belongs to the technical field of welding materials and preparation of the welding materials. The welding wire solves the problem that the low-temperature performance of a welding seam is poor when the current welding wire for the liquid hydrogen storage tank is used for welding. The welding wire comprises the following chemical components in percentage by mass: less than or equal to 0.02% of C, 0.4-1.5% of Si, 5.0-7.5% of Mn, less than or equal to 0.020% of S, less than or equal to 0.030% of P, 16.0-22.0% of Cr, 15.0-18.0% of Ni, 2.0-5.0% of Mo, 0.05-0.2% of N, less than or equal to 0.01% of O and the balance of Fe and inevitable impurities. According to the welding wire, deposited metal is low in low-temperature embrittlement tendency, high in low-temperature strength and excellent in low-temperature impact and fracture toughness. The welding wire is used for welding the austenitic stainless steel liquid hydrogen storage tank and is wide in application range, and the mechanical property of deposited metal is good.

A groove (6) is provided on an upper surface of a heat sink (5) along an outer periphery of an insulating substrate (1). A first solder joint material (7) is filled in the groove (6). A second solder joint material (8) is provided on the upper surface of the heat sink (5) and the first solder joint material (7) and joins the upper surface of the heat sink (5) and the first metal pattern (1b). The first solder joint material (7) and the second solder joint material (8) are of different types. A melting point of the first solder joint material (7) filled in the groove (6) is lower than a melting point of the second solder joint material (8).

The invention relates to the field of solder materials, and provides a non-ferrous metal solder for low-temperature brazing and application, the solder is composed of carbon-coated copper nanorods, tin-bismuth alloy-coated silver nanoparticles, 2-mercaptobenzimidazole, rosin resin, an organic active agent, a dispersing agent, ionic liquid, hydroxyethyl cellulose, indium nitrate and citric acid. The silver particles are of a core-shell structure and are coated with tin-bismuth alloy layers, and continuous carbon layers are formed on the surfaces of the copper nanorods, so that the conductivity and the interface stability of the solder are effectively improved. The non-ferrous metal solder with excellent conductivity, low melting point and good wettability is prepared through step-by-step mixing, hot press molding and low-temperature heat treatment processes, and is suitable for electronic device packaging, power device connection and flexible circuit interconnection, and the defects of existing solder in the aspects of low-temperature welding and high conductivity are overcome.

The invention provides a manufacturing method of an Al-Cu series aluminum alloy bright welding wire. The manufacturing method comprises the steps of burdening, smelting, casting, uniform heating, peeling, hot rolling, primary annealing, primary cold rolling, secondary annealing, secondary cold rolling, third annealing, intermediate drawing, fourth annealing, scraping, finish drawing, cleaning, drying and layer winding. By optimizing the composition and the processing technology of the welding wire, the prepared welding wire is high in strength and good in processing performance, welding and welding joints do not exist in the production process of the welding wire, and the consistency of the structure and overall deformation of the welding wire is ensured. A finished product can be manufactured into a disc-loaded welding wire or a barrel-loaded welding wire with a large weight, and welding materials with higher quality and higher efficiency are provided for automatic welding.

The automatic welding device comprises a base, a lifting platform, a material box, a thrust assembly, a welding nozzle, a pin conveying module and a pin box, the lifting platform is installed on the base and used for driving the material box, the thrust assembly and the welding nozzle to move up and down; the pin box is used for storing pins; the pin conveying module is used for taking out the pins stored in the pin box and conveying the pins to the position below the welding nozzle. The material box is used for storing welding materials; a plurality of welding nozzles are arranged, and each welding nozzle is communicated with the material box; according to the welding device, metal is heated to be in a molten state through the heater in the material box, then molten metal is sprayed to the welding position through the welding nozzle, and after the metal is cooled, welding of the pins and the electrodes is completed; through the mode, a plurality of pins can be simultaneously welded on a plurality of storage batteries according to a specified arrangement mode, so that the working efficiency is greatly improved.

The invention belongs to the technical field of welding materials, and particularly relates to efficient scaling powder and a preparation method thereof. The efficient scaling powder is composed of, by mass, 4%-10% of organic acid activating agents, 1%-2% of thiourea reinforcing agents, 0.15%-0.3% of wetting agents, 0.2%-0.6% of antioxidants, 0.3%-0.5% of surfactants, 0.05%-0.2% of defoaming agents, 3%-5% of film forming agents, 10%-15% of solvents and the balance water. The prepared scaling powder has good spreadability, stability, corrosion resistance and the like.

The invention belongs to the technical field of electronic packaging and welding materials, and relates to lead-free solder powder for reflow soldering and a preparation method of the lead-free solder powder. The lead-free solder powder is based on a Sn-Ag-Cu alloy system, and melt purification, beta-Sn grain refinement and interface IMC stabilization are achieved by compositely adding trace Ce and Ni elements. The Sn-Cu-Ce alloy comprises the following components in percentage by mass: 2.9%-3.1% of Ag, 0.45%-0.55% of Cu, 0.01%-0.10% of Ce, 0.01%-0.05% of Ni and the balance of Sn and impurities. During preparation, a Ce-Ni intermediate alloy is adopted to introduce microalloy elements, and the spherical solder powder is obtained through vacuum melting, inert gas atomization and surface treatment. The obtained solder powder is low in oxygen content, good in wettability, slow in interface IMC growth after backflow, high in welding spot strength and excellent in thermal cycle reliability, and is suitable for the field of high-reliability electronic packaging.

The invention relates to low-temperature lead-free formic acid solder paste and a preparation method and application thereof, and belongs to the technical field of welding materials. The low-temperature lead-free formic acid solder paste is prepared from the following raw materials in percentage by mass: 85-90% of alloy welding powder and 10-15% of scaling powder, the soldering flux comprises the following raw materials in parts by weight: 10-15 parts of an activating agent, 1-5 parts of a rheological agent, 20-30 parts of an organic solvent, 20-30 parts of a paste forming agent, 3-5 parts of a surfactant and 0.1-0.5 part of a corrosion inhibitor, the activating agent is a composition of hydrogenated dimer acid, glycollic acid and ethylenediaminetetraacetic acid, and the organic solvent is a composition of tetrahydrofurfuryl alcohol and cyclohexanol. The paste forming agent is polyethylene glycol. The solder paste is suitable for a low-temperature welding process at the temperature of 120-150 DEG C, welding energy consumption can be reduced, the residual rate after welding is low, follow-up cleaning is not needed, the production environment can be improved, and the production cost can be reduced.

The invention relates to the technical field of welding materials, in particular to a titanium carbide reinforced iron-based wear-resistant corrosion-resistant flux-cored wire for surfacing on the surface of a conveying roller. According to the specific technical scheme, the flux core comprises, by mass, 10%-20% of graphite, 25%-35% of ferrotitanium, 2%-6% of ferrovanadium, 3%-8% of electrolytic manganese metal, 2%-10% of ferromolybdenum, 5%-15% of ferrosilicon, 2% of aluminum-magnesium alloy and the balance Fe powder. According to the flux-cored wire prepared through the flux core, the surfacing alloy obtained through electric arc surfacing is good in surfacing manufacturability, attractive in weld joint forming and small in surface air hole number, and the flux-cored wire has high hardness, high-temperature abrasion resistance and corrosion resistance.

The invention discloses an intelligent distribution system for welding material management and an operation method thereof, and relates to the technical field of welding material pretreatment equipment, and the intelligent distribution system structurally comprises a drying box, a feeding device and a material taking distribution device. A plurality of layers of sliding frames are arranged in the drying box, and material frames are arranged on the sliding frames and can slide out from one side. The feeding device comprises a transferring mechanism and a feeding table, and the transferring mechanism is used for transferring the material frame between the drying box and the feeding table. The material taking and distributing device comprises a mechanical arm and a grabbing mechanism and is used for grabbing and transferring the welding materials in the drying box. The operation method comprises the steps that 1, empty material frames in the drying box are taken out through the transferring mechanism and placed on the workpiece feeding table; 2, a welding material is supplemented into the material frame; 3, taking down the filled material frame through a transferring mechanism, and feeding the material frame into a drying box for drying; and 4, the welding materials are grabbed from the drying box through a material taking and distributing device and put in. By applying the scheme, the technical problems that in the prior art, the working intensity of workers is large, the environment is poor, and whole-process automation is difficult to achieve can be solved.

Microelectronic assemblies, related devices and methods, are disclosed herein. In some embodiments, a microelectronic assembly may include a first die, having a first surface and an opposing second surface, in a first layer; a redistribution layer (RDL) on the first layer, wherein the RDL includes conductive vias having a greater width towards a first surface of the RDL and a smaller width towards an opposing second surface of the RDL; wherein the first surface of the RDL is electrically coupled to the second surface of the first die by first solder interconnects having a first solder; and a second die in a second layer on the RDL, wherein the second die is electrically coupled to the RDL by second solder interconnects having a second solder, wherein the second solder is different than the first solder.

The invention provides an aluminum steel friction welding method based on additive and subtractive microtexture interlocking and regulation, which comprises the following steps: constructing a surface subtractive microtexture in a to-be-welded area of an aluminum plate to obtain a to-be-welded aluminum plate, constructing an additive microtexture matched with the surface subtractive microtexture in a to-be-welded area of a steel plate by using alloy powder to obtain a to-be-welded steel plate, and welding the to-be-welded steel plate with the additive microtexture. Then, after the surface subtractive microstructure on the to-be-welded aluminum plate and the additive microstructure are matched to form an interlocking structure, welding is conducted through a friction welding technology; in the friction welding process, a friction welding tool head acts on the top face of the steel plate. Compared with traditional friction stir welding, the friction stir welding method has the advantages that under the condition that the physical form of the microstructure of the base metal is not changed, by means of continuous layered distribution of the brittle phase of the microstructure discrete interface of the high-entropy alloy, hole outlet of a welding material is avoided, and the strength of a joint is improved.

The invention provides a wind generating set tower tube weld joint optimization method based on hydrodynamics, and relates to the technical field of hydrodynamics, the wind generating set tower tube weld joint optimization method comprises the following steps: obtaining an image of a junction of to-be-welded positions of a wind generating set tower tube, and extracting a junction center line in the image of the junction; according to the extension direction of the boundary center line, a constraint condition for keeping energy continuity of the molten metal at the inflection point of the extension direction is constructed, and the heat flux density formed by the molten metal at the inflection point of the center line is calculated; according to the heat flow density needing to be met in the step S2, the welding heat needing to be absorbed by the to-be-welded material when the welding seam is formed at each inflection point of the tower barrel welding seam is calculated; and a welding parameter-inflection point heat mapping model is constructed, optimal welding parameters are output through a global optimization algorithm, the fatigue strength of a welding seam under the wind load effect is improved, and the service life of a tower drum of the wind generating set is prolonged.

The application belongs to the technical field of welding materials, and discloses a preformed soldering sheet and a preparation method thereof, the preparation method comprising: a flux preparation method, wherein benocyclobutene resin, a thixotropic agent, an active agent, a surfactant, an antioxidant, a corrosion inhibitor and a solvent are weighed, mixed and heated and stirred to mix, and then cooled to obtain the required flux; a processing method of a preformed soldering sheet body soldering strip, wherein lead-free filler metal is melted at high temperature to form a soldering strip; and a preformed soldering sheet preparation method, wherein the soldering strip is uniformly coated with the flux by a coating machine, and the flux is cured and attached to the soldering strip after baking; the preformed soldering sheet is obtained by the above preparation method. The application realizes improved welding quality of the soldering sheet coated with the flux film and solder metal oxidation resistance, and the preformed soldering sheet has high stability, good wettability and good weldability, and can meet the requirements of the market for the use of the preformed soldering sheet with low cavities.

The invention relates to the technical field of semiconductor packaging materials, and particularly discloses a water-soluble solder paste for a semiconductor chip, and the solder paste comprises the following components by taking the total mass of the solder paste as 100%: 60-70% of alloy powder, the mass content of tin powder is not less than 37.8%, and the alloy powder contains metal elements for improving the heat-conducting property; the conductive adhesive is used for enhancing the conductivity and the bonding strength of the solder paste; the solder paste comprises the following components in percentage by weight: 20%-30% of soldering flux which comprises an organic acid chelating agent, a surfactant, a corrosion inhibitor, an organic solvent and deionized water and is used for promoting the welding process and reducing residues after welding, and 0%-5% of other additives which comprise an antioxidant, a thixotropic agent and a flatting agent and are used for improving the storage stability and construction performance of the solder paste. According to the water-soluble solder paste, the high-purity alloy powder is adopted, the mass content of the tin powder is not lower than 37.8%, metal elements for improving the heat conduction performance are introduced, and high heat conduction performance and low resistivity of a welding material are guaranteed.