5326results about "Soldering media" patented technology

The invention provides a pre-buried brazing flux aluminum alloy brazing filler metal plate blank and a preparation method thereof, a pre-buried brazing flux composite aluminum alloy brazing plate strip and a preparation process and application thereof. After the mixed powder of the aluminum-silicon alloy and the brazing flux is pressed into the cylinder, the cylinder is extruded into the aluminum alloy brazing filler metal plate blank with the pre-embedded brazing flux through the semi-continuous extruding machine, the production efficiency is high, the yield is high, and the prepared aluminum alloy brazing filler metal plate blank with the pre-embedded brazing flux is uniform in component and good in extensibility. The prepared pre-buried brazing flux aluminum alloy brazing filler metal plate blank and an aluminum alloy core material are easy to roll and compound, the obtained pre-buried brazing flux composite aluminum alloy brazing plate strip has a good compound interface, does not have obvious defects such as slag inclusion, bubbles, layering and peeling, has the mechanical property meeting the requirements, has excellent ductility and good brazing performance, and is suitable for large-scale production. And the brazing effect with other aluminum components is good, the surface of a workpiece is bright, and soldering flux traces are not left. The technology can greatly simplify the manufacturing process of the aluminum heat exchanger, and can be used for large-scale industrial production.

A component includes a body and an additively manufactured (AM) metal coupon that includes at least one first porous region having a first porosity and may include any number of second porous regions having a second porosity different than the first porosity. A braze material couples the metal coupon in a coupon opening in the body. The braze material infiltrates into at least one of the first porous region based at least on a characteristic of the first porosity or any second porous region based at least on a characteristic of the second porosity. The different porosities can be customized to provide the first porous region and the second porous region with the braze material therein with different physical characteristic(s).

A metal coupon for repairing a component includes an additively manufactured (AM) metal member having a low porosity region in an interior of the AM metal member, and a porous region around the low porosity region. The low porosity region may have a porosity in a range of 0% to 5%, so is solid or nearly solid. The porous metal coupon with low porosity region allows braze material to be directed based on characteristics of the porous region.

The invention relates to a metal sample block with a porous area for a component and the component with the metal sample block. A component (202) includes a body (206) and an additive manufactured (AM) metal sample block (200) that includes at least one first porous region (300A) having a first porosity and can include any number of second porous regions (300B) having a second porosity different from the first porosity. A braze material (310) couples the metallic sample block (200) in a sample block opening (204) in the body (206). The braze material (310) is infiltrated into at least one of the first porous region (300A) and any second porous region (300B) based at least on a characteristic of the first porosity and at least on a characteristic of the second porosity. Different porosities can be tailored to provide different physical characteristics for the first porous region (300A) and the second porous region (300B) having the braze material (310) therein.

The invention relates to the technical field of welding wire preparation, in particular to a nickel-based alloy flux-cored wire for 9Ni steel welding and a preparation method of the nickel-based alloy flux-cored wire. A nickel-based alloy flux-cored wire for 9Ni steel welding comprises a flux core, and the flux core comprises, by weight, 26%-34% of titanium dioxide, 3%-5% of ferrozirconium, 8%-12% of ferrotitanium, 1%-3% of rare earth ferrosilicon, 15%-20% of tungsten powder, 1%-2% of polytetrafluoroethylene and the balance pretreated mixed powder. The nickel-based alloy flux-cored wire for 9Ni steel welding has the advantages that low-melting-point eutectic is not prone to being formed, the hot crack sensitivity is reduced, the nickel-based alloy flux-cored wire is suitable for welding of restrained large structures, the deoxidation and denitrification capacity is enhanced, and the pore sensitivity is reduced.

The invention discloses a high-strength silver-free copper-based brazing filler metal which is composed of P, Sn, Ni and Cu. The high-strength silver-free copper-based brazing filler metal is low in cost, safe, environmentally friendly and good in welding effect; through the adding of Sn and Ni, the melting point of brazing filler metal alloy is reduced, and the tensile strength and wettability of the brazing filler metal alloy are enhanced.

The cavitation-erosion-resistant martensite welding wire comprises powder and a welding skin, and the powder comprises, by mass, 20.0%-25.0% of Cr powder, 25.0%-30.0% of Ni powder, 5.0%-8.0% of Mo powder, 3.0%-5.0% of Nb powder, 3.0%-5.0% of W powder, 0.5%-1.0% of C powder, 4.0%-6.0% of B powder, 0.8%-1.0% of Y2O3 powder and the balance Fe powder. The welding wire is specially used for solving the problem of frequent cavitation failure of the turbine runner. The invention further discloses a preparation method of the cavitation-erosion-resistant martensite welding wire for the water turbine runner.

The invention belongs to the technical field of nickel-based alloy welding wires, and discloses a corrosion-resistant nickel-based alloy welding wire and a production process thereof, and the corrosion-resistant nickel-based alloy welding wire comprises the following components in percentage by mass: 50-65% of nickel, 16-24% of chromium, 8-10% of molybdenum, 3.5-5.5% of niobium and tantalum, 3-4.5% of copper, 3-4% of tungsten, 0.5-1.0% of tin, 0.1-0.3% of rare earth element, 0.1-0.5% of grain boundary optimizer, 2-5% of nano reinforced phase and the balance of Fe and other inevitable impurities. Through multi-element alloying design, nano reinforced phase compounding and gradient coating synergistic effect, comprehensive improvement of corrosion resistance, high-temperature mechanical property and welding manufacturability is achieved; a welding wire base body is based on nickel, a compact and self-repairing gradient oxidation film is formed by accurately regulating and controlling the atomic proportion of chromium, molybdenum and tungsten, and the chloride ion permeation resistance and the high-temperature oxidation resistance are remarkably improved; therefore, the welding wire has excellent corrosion resistance, high-temperature strength and welding adaptability.

The invention relates to a crack repairing method for an additive manufacturing nickel-based high-temperature alloy part, and relates to the technical field of high-temperature alloys. According to the main technical scheme, filler powder and solder powder are adopted for conducting crack repairing on the additive manufacturing nickel-based high-temperature alloy part; wherein the solder powder comprises the following chemical components in percentage by weight: 11.0 to 17.0 weight percent of Cr, 5.0 to 9.0 weight percent of W, 1 to 4 weight percent of B, less than or equal to 0.06 weight percent of C, less than or equal to 0.1 weight percent of Co and the balance of Ni; wherein the filler comprises the following chemical components in percentage by weight: 6 to 10 weight percent of Cr, 6 to 10 weight percent of Co, 6 to 10 weight percent of W, 0.5 to 3 weight percent of Mo, 3 to 6 weight percent of Al, 0.5 to 2 weight percent of Ti, 3 to 6 weight percent of Ta, less than or equal to 0.2 weight percent of C, less than or equal to 0.1 weight percent of B, less than or equal to 2 weight percent of Hf and the balance of Ni; the additive manufacturing nickel-based superalloy comprises the following chemical components in percentage by weight: 6 to 10 percent of Cr, 6 to 10 percent of Co, 6 to 10 percent of W, 0.5 to 3 percent of Mo, 3 to 6 percent of Al, 0.5 to 2 percent of Ti, 3 to 6 percent of Ta, less than or equal to 0.2 percent of C, less than or equal to 0.1 percent of B, less than or equal to 2 percent of Hf and the balance of Ni. The method is mainly used for solving the problem of repairing and remanufacturing the cracks of the additive manufacturing nickel-based superalloy part, and has important application value.

The invention provides an aluminum alloy brazing composite material, an Al-Zn-based pre-buried brazing flux plate blank and a preparation method of the Al-Zn-based pre-buried brazing flux plate blank and relates to the technical field of aluminum alloys, and the aluminum alloy brazing composite material sequentially comprises a non-brazing filler metal layer and a brazing filler metal layer; the non-brazing filler metal layer sequentially comprises a core layer and an Al-Zn-based pre-embedded brazing flux layer, and the Al-Zn-based pre-embedded brazing flux layer is arranged close to the brazing filler metal layer; the Al-Zn-based pre-embedded brazing flux layer comprises an Al-Zn alloy and a fluorine-containing brazing flux; the Al-Zn series alloy comprises 1-12 wt% of Zn element according to the mass fraction, the Al-Zn based pre-buried brazing flux layer has dislocation, and the dislocation density of the Al-Zn based pre-buried brazing flux layer is 2.5-4.0 * 10 < 14 > / m < 2 >; and the core layer and the Al-Zn-based pre-embedded brazing flux layer cannot be melted during brazing. The problem that the yield strength after welding is insufficient due to the fact that the proportion of the core layer in the aluminum alloy brazing composite material is reduced can be solved.

A tubing assembly is provided that can comprise a plurality of tubes or lumens that can be disposed within a head of a peristaltic pump. The tubing assembly can provide a flow rate or volume capacity that is generally equal to or greater than that achieved with a comparable prior art tube while operating at higher pressures than that possible using the prior art tube. Further, in accordance with some embodiments, the tubing assembly can achieve a longer working life than a comparable prior art tube, and the load on the pump motor can be reduced such that the pump life is increased and / or a larger pump motor is not required to achieve such advantageous results.

The invention relates to the technical field of circuit substrate manufacturing, and particularly discloses a preparation method of a composite solder sheet and an AMB ceramic copper-clad plate. The composite solder sheet is composed of an active metal foil and a copper-containing layer modified on the surface of the active metal foil, and the preparation method of the copper-clad plate comprises the following steps: after the surface of the active metal foil is pretreated, the copper-containing layer is deposited to prepare the composite solder sheet, and the composite solder sheet is placed between a copper substrate and a ceramic sheet to be pressed and assembled. And performing vacuum brazing on the assembly to complete the preparation of the ceramic copper-clad plate. A composite solder sheet containing active metal is adopted, high-temperature element diffusion during vacuum brazing is utilized at the diffusion temperature to achieve alloying of a composite solder layer, and then heat preservation is conducted at the brazing temperature to achieve uniform melting of solder and wetting metallurgical reaction between the solder and copper and between the solder and a ceramic substrate. By means of the preparation method, low-cost and high-reliability preparation of the AMB ceramic copper-clad plate can be achieved, and the prepared AMB ceramic copper-clad plate also has high peel strength and lower weld porosity.

A method of manufacturing a brazing sheet includes layering at least a core-material slab composed of an aluminum material and a filler-material slab composed of an Al—Si series alloy to prepare a clad slab. At least one aluminum slab in the clad slab, which is disposed in a range from the core-material slab to the filler-material slab inclusive, contains a metal element that oxidizes more readily than Al. The clad slab is hot rolled to prepare a clad sheet that includes a core material composed of the core-material slab and a filler material composed of the filler-material slab. Then, one or more passes of cold rolling is performed on the clad sheet. Between passes of cold rolling or after completion of the cold rolling, at least one surface of the clad sheet is etched using an alkaline etching solution having a sodium hydroxide concentration of 0.05-1.0 mass %.

A tool includes a cemented carbide part and a maraging steel part, wherein the two parts are joined by brazing. The cemented carbide part has a hard phase embedded in a metallic binder phase matrix. The maraging steel part has a hardness of between 350 and 600 HV1 with a standard deviation between 0 and 20 HV1. A method of making such tool is also provided.

The present application relates to the technical field of solder paste. The present application discloses a high-precision nano solder paste and a preparation method thereof. The high-precision nano solder paste comprises solder powder, flux, glucomannan and polyethylene glycol modified aliphatic epoxy resin; the raw material composition of the flux comprises: an active agent, a surfactant, a thixotropic agent, an antioxidant, a corrosion inhibitor, a film former and a solvent. The preparation method comprises the following steps: stirring and mixing the active agent and the solvent to prepare a premixed liquid; adding a surfactant, a thixotropic agent, an antioxidant, a film former and a corrosion inhibitor to the premixed liquid in sequence, stirring and mixing to prepare a flux; mixing and stirring the solder powder, flux, glucomannan and polyethylene glycol modified aliphatic epoxy resin, grinding and preparing a high-precision nano solder paste. The high-precision nano solder paste prepared in the present application has good storage stability, long service life, high expansion rate and good wetting performance.

The invention provides a solid welding wire for 1000 MPa high-strength steel, a preparation method and a welding method. The welding wire comprises the following chemical components in percentage by weight: 0.05-0.12 wt% of C, 1.80-2.10 wt% of Mn, 0.55-0.90 wt% of Si, less than or equal to 0.025 wt% of P, less than or equal to 0.025 wt% of S, 1.05-1.40 wt% of Cr, 2.80-3.10 wt% of Ni, 0.50-0.85 wt% of Mo, 0.030-0.085 wt% of Ti, 0.020-0.060 wt% of V, 0.20-0.30 wt% of Cu, the mass ratio of Cr to Ti + V is greater than or equal to 10, and the mass ratio of Ni to Cr + Mo is greater than or equal to 1.5. And the balance of Fe. The welding wire has good comprehensive mechanical properties and is suitable for welding of 1000MPa-grade high-strength steel.

The invention discloses coating type preformed brazing filler metal and a preparation method and application thereof, and belongs to the technical field of brazing, the coating type preformed brazing filler metal comprises brazing filler metal and brazing flux wrapping the periphery of the brazing filler metal, the brazing filler metal comprises aluminum-silicon alloy, and the brazing flux comprises fluoroaluminate; the mass ratio of the aluminum-silicon alloy to the fluoroaluminate is (75-96): (4-25). According to the method, the outer surface of the aluminum-silicon alloy is coated with the fluoroaluminate, the brazing flux can effectively remove an oxidation film on the surface of brazing filler metal and an oxidation film on a welding interface, the welding quality is improved, and then the product yield is improved.

The invention discloses a dissimilar metal friction welding interface regulation and control layer and an aluminum steel friction welding method. The dissimilar metal friction welding interface regulation and control layer comprises a micro-texture arranged on the metal surface, paste is laid at the micro-texture, and non-metal substances in the paste are completely volatilized before dissimilar metal metallurgical bonding; the welding method comprises the steps that a microstructure is prepared in a designated area on the surface of a stainless steel plate, Zn-20Al powder and ethyl alcohol are mixed and stirred into paste, then the paste is evenly laid on the microstructure area on the surface of base metal, and then friction stir welding is conducted. A welding joint obtained through the scheme is good in toughness (plasticity) and high in strength, atomic-level tight combination of a joint interface is achieved, the mechanical property of the joint is excellent, the joint is free of air hole and crack defects, the adverse effect of brittle intermetallic compounds on the mechanical property is weakened, the wetting spreading performance and the element diffusion capacity of the interface are enhanced, and the welding quality is improved. The obtained welding joint has a good mechanical embedding characteristic.

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 discloses a flux-cored wire for extra-thick marine steel high heat input EGW and a preparation method of the flux-cored wire, and relates to the technical field of metal welding, the flux-cored wire comprises an outer skin of a double-layer alloy steel strip and powder filled in the outer skin, the filling rate of the powder is 20 + / -5%, and the powder comprises Fe, Mn, Si, Cr, Ni, Mo, V, B, S, Al, MgAl2O4, MgO-TiO2, ReOx and a slag former. According to the preparation method, the metal powder is positively charged, the rare earth nanoparticles are negatively charged through an electrostatic self-assembly technology, the metal powder and the rare earth nanoparticles are mixed with a slag former after being mixed, filtered and freeze-dried, an alloy steel strip is filled with the powder, and then rolling and drawing forming is conducted. In the welding process, the composite inclusions form a core-shell structure, a weld metal structure is regulated and controlled, acicular ferrite nucleation is promoted, and grains are refined, so that the low-temperature toughness and crack arrest performance of a weld are remarkably improved, the rare earth elements are beneficial for changing irregular inclusions into spheres, nucleation sites are increased, interface energy is reduced, and the nucleation rate of acicular ferrite is increased.

The invention relates to the technical field of stainless steel flux-cored wires, in particular to a flux-cored wire for low-cost duplex stainless steel and a preparation method of the flux-cored wire. At present, no stainless steel flux-cored wire for all-position welding of the S32001 duplex stainless steel pipe is developed on the market. In order to solve the technical problems, the low-cost flux-cored wire for the duplex stainless steel is provided, a duplex stainless steel flux-cored wire all-position welding material matched with an S32001 duplex stainless steel pipe is developed through component research and analysis of the S32001 duplex stainless steel pipe and a large number of experimental researches, and the material is low in Ni content, low in cost and good in welding effect. The S32001 duplex stainless steel pipe is simple in structure, good in welding stability and excellent in comprehensive mechanical property, the innovation powerfully promotes wide application of the S32001 duplex stainless steel pipe in urban underground pipeline construction, and extremely high practical value is shown.

Provided is a brazing sheet exhibiting excellent brazing properties where an aluminum material is brazed in an inert gas atmosphere such as a nitrogen gas atmosphere without using a flux. The aluminum alloy brazing sheet used for brazing in an inert gas atmosphere without using a flux, the aluminum alloy brazing sheet comprises: a core material; and a brazing material cladded on one side surface or both side surfaces of the core material, in which the core material is formed of aluminum or an aluminum alloy, the brazing material comprises 4.00 mass % to 13.00 mass % of Si and comprises 0.10 mass % to 2.00 mass % of Mg, with the balance being Al and inevitable impurities, and an integral value of Mg from a surface of the brazing material to a depth of 60 nm is 30 at %×nm to 600 at %×nm.

The invention relates to the technical field of welding, in particular to a lead-free solder composition and a preparation method thereof. The composition comprises brazing filler metal and a brazing flux, wherein the brazing filler metal comprises 55 to 65 parts of copper, 30 to 40 parts of zinc, 0.5 to 1 part of silver, 0.1 to 1 part of tin, 0.1 to 0.5 part of nickel, 0.02 to 0.15 part of lanthanum, 0.03 to 0.15 part of cerium and 0.05 to 0.2 part of indium; the brazing flux comprises 18-22 parts of borax, 13-17 parts of boric acid, 25-32 parts of a potassium fluoride and potassium fluoborate compound, 3-5 parts of calcium fluoride, 12-16 parts of aluminum oxide and 8-11 parts of magnesium oxide. The lead-free solder composition does not contain toxic lead elements, pollution to the environment and the ecological system is little, the wettability, corrosion resistance, strength, stability and the like of the lead-free solder composition are improved, and the welding quality is comprehensively improved. According to the preparation method, uniform distribution and accurate control of the brazing filler metal and the brazing flux are guaranteed, stability and consistency of product quality are guaranteed, and the preparation method is easy and convenient to operate and suitable for mass production.

The invention discloses preformed coating brazing filler metal and a preparation method and application thereof, and belongs to the technical field of brazing, the preformed coating brazing filler metal comprises brazing filler metal and brazing flux wrapping the periphery of the brazing filler metal, the brazing filler metal comprises zinc-aluminum alloy, and the brazing flux comprises an active agent and a film forming matter; the active agent comprises fluoroaluminate; the mass ratio of the zinc-aluminum alloy to the fluoroaluminate is 100: (4-12); the film forming substance comprises a self-crosslinking emulsion, and the mass ratio of the self-crosslinking emulsion to the active agent is (0.3-1): 100. The preformed coating brazing filler metal can well fill a battery cell tab structure, the production yield is improved, the brazing flux wrapping the outer surface in advance is used for improving the production efficiency and the yield, the self-crosslinking emulsion is added to serve as a film forming substance, the welding quality can be effectively improved, the brazing flux is prevented from falling off, and the welding quality is improved. And the welding void rate is effectively reduced.

The invention belongs to the technical field of stainless steel surface processes, and particularly relates to a 430 stainless steel surface defect prevention method which comprises the following steps: (1) adjusting the pressure of a side guide head part according to the thickness of a steel belt; (2) adding a program to enable the coiling tension to identify the coiling weight; (3) the rigidity precision of the pinch roll is improved; (4) additionally arranging vertical wheels on the working side and the transmission side of the side guide; (5) pre-treating the new wrapper roller by adopting a roller ironing process after the new wrapper roller is put on a machine; (6) a welding rod made of a 1Cr13 material cannot be used, and a W-shaped staggered welding process is adopted between welding beads; (7) the head CT precision in the coiling process is precisely controlled by adjusting the heat conduction coefficient of each cooling section and the target temperature of the cooling section; (8) controlling the roll gap of the wrapper roll to display the actually measured deviation; (9) the blocked water nozzle is found in time, and the water nozzle with the small flow is still replaced after manual dredging; and (10) a powder wear-resistant lining plate is adopted as the lining plate. According to the method, the surface defect problems of pinch roll scratches and wrapper roll marks are reduced, and the product percent of pass is increased.

This invention discloses a stainless steel welding wire for repair welding of martensitic stainless steel turbine runners, its preparation method, and its application, belonging to the field of metal welding material preparation technology. The chemical composition of the welding wire provided by this invention, expressed as a percentage by weight, is: C≤0.03%, Si: 0%~0.6%, Mn: 5.0%~8.0%, S≤0.010%, P≤0.020%, Cr: 12.5%~15.5%, Ni: 5.0%~7.0%, Mo: 1.0%~2.0%, with the balance being Fe and impurities. The welding wire provided by this invention is suitable for repair welding of Cr13Ni4~6 type martensitic stainless steel, and post-weld heat treatment is not required. The weld metal produced by this welding wire exhibits good strength, plasticity, and toughness, with a tensile strength ≥750MPa, elongation after fracture ≥35%, and impact absorption energy at -40℃ ≥120J.

The invention discloses low-silver lead-free tin-based solder paste and a preparation method thereof, and belongs to the field of welding materials. The soldering paste is composed of 85 wt%-87.5 wt% of tin-based powder brazing filler metal and 12.5 wt%-15 wt% of scaling powder, wherein the tin-based powder brazing filler metal comprises 0.35 wt%-0.6 wt% of Ag, 0.5 wt%-0.8 wt% of Cu, 1.0 wt%-4.0 wt% of Bi, 0.05 wt%-0.08 wt% of Ni and the balance Sn; the soldering flux is composed of rosin, a solvent, an active agent, a thixotropic agent, a film-forming agent, a PH regulator, a surfactant, a phenolic antioxidant and a corrosion inhibitor. The soldering paste has excellent low residue, good wettability and welding reliability, and is especially suitable for surface mount technology (SMT) in the electronic and electric appliance industry.

Provided is a flux that can suppress the generation of voids when an indium alloy sheet is used to perform a continuous reflow under different temperature conditions. The present invention employs a flux that contains a rosin ester, an organic acid (A), and a solvent (S). The organic acid (A) includes a dimer acid (A1) that demonstrates a weight reduction rate of not more than 1 mass % in a thermogravimetric analysis in which the dimer acid is heated up to 260° C. at a temperature rising rate of 10° C. / min. The solvent (S) includes a solvent (S1) that demonstrates the weight reduction rate of at least 99 mass % in a thermogravimetric analysis in which the solvent (S1) is heated up to 150° C. at a temperature rising rate of 6° C. / min.

The invention belongs to the field of nickel-based alloy materials, and discloses a precipitation hardening type nickel-based alloy welding wire and a preparation method thereof.The precipitation hardening type nickel-based alloy welding wire comprises, by mass, 50%-60% of nickel, 15%-20% of chromium, 15%-20% of iron, 2%-4% of molybdenum, 2%-5% of niobium, 0.01%-2% of tantalum, 0.2%-2% of aluminum, 0.5%-1.2% of titanium, 0.03%-0.08% of carbon, 0.1%-0.5% of manganese, 0.1%-0.5% of silicon, 0.01%-0.05% of magnesium, 0.01%-0.05% of yttrium, 0.5%-2% of tungsten, 0.1%-0.6% of cobalt, 0.001%-0.02% of boron and the balance impurities; according to the precipitation hardening type nickel-based alloy welding wire and the preparation method thereof, through component optimization and process innovation, the nickel-based alloy welding wire with high-temperature strength, excellent hot crack resistance and welding toughness is provided.

The invention provides a high-hardness cobalt-based alloy welding wire and a preparation method thereof, and the high-hardness cobalt-based alloy welding wire comprises the following components in percentage by mass: less than or equal to 0.5% of C, 3-4% of Si, 15-20% of Cr, 1-4% of Ni, 25-30% of Mo, 45-55% of Co, less than or equal to 1% of Fe, less than or equal to 0.02% of La, less than or equal to 0.02% of B, less than or equal to 0.01% of S and less than or equal to 0.01% of P. According to the cobalt-based welding wire, through regulation and control of alloy elements, the hardness of the cobalt-based welding wire is remarkably improved, the uniformity of components of the welding wire is improved, the welding strength is improved, the size of the welding wire is extremely thin, and the welding manufacturability of the welding wire is improved.