Preparation process of high-strength gas shielded welding wire and high-strength gas shielded welding wire

Abstract

The invention relates to the technical field of welding materials, in particular to a high-strength gas shielded welding wire preparation process and a high-strength gas shielded welding wire thereof. The high-strength gas shielded welding wire preparation process comprises the following steps of pretreatment, preparation of a first copper layer through a chemical copper plating method, preparation of a second copper layer through an electro-coppering method, hole sealing and aftertreatment. The first copper plating solution comprises copper sulfate, sodium hypophosphite, sodium hydroxide, sodium dodecyl benzene sulfonate and a stabilizer, and the stabilizer comprises 2, 2 '-bipyridine and thiourea with the mass ratio being (2-3): 1; the second copper plating solution comprises copper sulfate, sodium methanesulfonate, a boric acid-triethanolamine buffer solution, potassium perfluorooctane sulfonate and additives, and the additives comprise polyaspartic acid and thiobetaine; the blocking solution comprises an acrylic emulsion and aziridine. According to the high-strength gas shielded welding wire obtained through the preparation technology, the ideal and uniform copper plating layer thickness with good adhesive force can be obtained, and the stability of all properties of the high-strength gas shielded welding wire is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of welding materials, and in particular to a preparation process of a high-strength gas shielded welding wire, the high-strength gas shielded welding wire and applications thereof. Background Art

[0002] With the development of automatic welding, gas shielded copper-plated solid welding wire is suitable for all-position welding. It has the advantages of fast welding speed and high deposition efficiency. It is widely used in the automotive industry, shipbuilding industry, construction industry and other fields in my country. With the rapid growth of the application of gas shielded welding wire in different fields, in order to ensure the performance of welding wire, welding wire is generally copper-plated on its surface. The main component of the copper plating solution in the traditional welding wire chemical copper plating process is copper sulfate (CuSO 4 ) and sulfuric acid (H 2 SO 4 ), copper sulfate provides Cu 2+ Ions are the source of copper metal; sulfuric acid plays two roles in the copper plating process: one is to activate the surface of the welding wire; the other is to stabilize the plating solution to prevent the hydrolysis of copper sulfate and precipitation. In addition to the main chemical components, the copper plating solution sometimes also contains NaCl or some other additives to increase the brightness of the welding wire surface.

[0003] The Chinese invention patent application with publication number CN102618857A discloses a method for chemical copper plating of welding wire, and the process steps are as follows: first, the surface of the ER50-6 welding wire to be treated is degreased and activated; then the surface treated welding wire is placed in a copper plating solution for chemical copper plating; then the copper-plated welding wire is washed with water and then passivated and polished; finally, the passivated and polished welding wire is dried and coiled for packaging.

[0004] The copper plating quality of the above process is good, and it can be reliably combined with rapid plating; the copper plating of welding wire is easy to carry out flow operation on the copper plating production line, and the wire speed of copper plating welding wire can reach 1-2m / s, which greatly improves the production efficiency, and has stable quality and low energy consumption. The copper layer obtained by the chemical copper plating process is relatively thin, generally 0.1-0.5 μm, and it is easier to obtain excellent copper plating adhesion, but in the continuous production process, the Cu in the copper plating solution 2+ is consumed, the concentration is decreasing, and Fe 2+ Produced, dissolved into the copper plating solution, Fe in the plating solution 2+The concentration gradually increases, which is not conducive to obtaining uniform copper plating quality. Chemical copper plating utilizes the strength of metal activity to obtain a copper layer through a chemical replacement reaction. Therefore, it is not easy to obtain an ideal copper plating thickness for welding wires containing some inactive alloy elements. In order to ensure the stability of the welding wire's conductivity, wire feedability, corrosion resistance and other properties, it is necessary to form a uniform coating on the surface of the gas shielded welding wire. If the copper plating on the surface of the gas shielded welding wire is uneven or does not reach the ideal thickness, the friction between the welding wire and the conductive nozzle in the conductive nozzle during welding will cause tiny copper flakes to fall off the surface of the welding wire and concentrate in the conductive nozzle. This is called "conductive nozzle blockage". This conductive nozzle blockage will lead to arc instability and wire feeding instability, and increase the amount of spatter.

[0005] The Chinese invention patent application with publication number CN118773685A discloses a high-speed copper plating solution for solid welding wire and its copper plating process, wherein the high-speed copper plating solution includes 32-46 parts of water-soluble copper salt, 5-8 parts of brightener, 20-27 parts of leveler, 4-12 parts of additive, 3-6 parts of inhibitor, 2-5 parts of accelerator, and 900 parts of deionized water; the additive is a mixture of 2-thiazoline polydithiopropane sulfonate sodium and N,N-dimethyldithiocarboxamide propane sulfonate sodium; the accelerator is selected from one or two of piperazine-1,4-dithiocarboxylic acid potassium salt or 2,3-dimercaptopropane sulfonic acid sodium salt. By optimizing various parameters of the electroplating process and the formula of the copper plating solution, the electroplating rate, tensile strength and corrosion resistance of the welding wire are significantly improved.

[0006] Using the above preparation process, copper ions (Cu 2+ ) gets electrons and deposits on the surface of the welding wire, which can produce a thicker copper layer. However, electroplating copper is accompanied by a slight degree of chemical replacement reaction, which has an adverse effect on the adhesion of copper plating. 2+ After that, and the surface Cu 2+ A substitution reaction occurs to generate "substitution copper", and then the Fe below the surface also loses electrons to precipitate Fe 2+ At this time, due to the electrochemical reaction, Cu 2+ The electrons are deposited into "electrical copper" and covered on the surface of the welding wire, making Cu 2+ Unable to reach below the surface to complete the replacement reaction, this will cause Fe 2+ A "void" is formed at the location of precipitation.

[0007] In summary, it is not easy to obtain a copper plating layer with ideal thickness, uniformity, stability and good adhesion using either chemical copper plating or electrolytic copper plating, which can easily cause instability in multiple properties of gas shielded welding wire. Summary of the invention

[0008] In order to solve the above problems, the present invention provides a preparation process of high-strength gas shielded welding wire and the high-strength gas shielded welding wire. The high-strength gas shielded welding wire prepared by the preparation process of the present invention can obtain an ideal, uniform and well-adhesive copper plating layer thickness, thereby ensuring the stability of various performances of the high-strength gas shielded welding wire.

[0009] In a first aspect, the present invention provides a preparation process of a high-strength gas shielded welding wire, the preparation process of the high-strength gas shielded welding wire comprising the following steps: The first copper layer is prepared by chemical copper plating: the first welding wire is placed in the first copper plating solution and chemically electroplated for 3-5 minutes at a temperature of 54-56° C. and a rotation speed of 3-5 m / min to form a first copper layer on the surface of the first welding wire, the first copper layer is immersed in a silane coupling agent with a concentration of 1% for 3-5 minutes, and then dried at a temperature of 55-60° C. to obtain a second welding wire; Preparation of the second copper layer by electroplating copper: Use the second copper plating solution to electroplate the second welding wire at a current density of 13-15A / dm 2 , electroplating copper at a temperature of 40-45° C. to form a second copper layer on the surface of the second welding wire to obtain the high-strength gas shielded welding wire; The first copper plating solution comprises, by mass, 15-20 parts of copper sulfate, 30-40 parts of sodium hypophosphite, 15-18 parts of sodium hydroxide, 0.01-0.05 parts of sodium dodecylbenzene sulfonate, and 0.05-0.1 parts of a stabilizer, wherein the stabilizer comprises 2,2'-bipyridine and thiourea in a mass ratio of 2-3:1; the second copper plating solution comprises 30-50 parts of copper sulfate, 60-100 parts of sodium methane sulfonate, 15-25 parts of boric acid-triethanolamine buffer, 0.1-0.5 parts of potassium perfluorooctane sulfonate, and 0.5-1 parts of an additive, wherein the additive comprises polyaspartic acid and thiobetaine in a mass ratio of 1-1.5:1; The mass ratio of the first copper plating solution to the second copper plating solution is 1:1.5-2.

[0010] In the above technical solution, copper sulfate in the first copper plating solution provides a copper source, and sodium hypophosphite serves as a reducing agent, providing electrons to release active H under alkaline conditions. - , reducing Cu 2+ For metallic copper, sodium hydroxide is used as a pH buffer to adjust the alkalinity and maintain the reaction environment. Sodium dodecylbenzene sulfonate is used as a wetting agent to reduce the surface tension of the first copper plating solution, so that the solution can quickly spread into the micropores or grooves, improve the uniformity of the first copper plating solution, and adsorb on the surface of the wire rod to replace the residual bubbles and prevent the gas from being trapped and forming pores. 2,2'-bipyridine can inhibit the occurrence of side reactions, prevent the spontaneous decomposition of the first copper plating solution, extend the service life of the first copper plating solution, and inhibit cuprous oxide (Cu 2O), avoiding the brittleness and decreased conductivity of the coating caused by the inclusion of oxides. Thiourea can work together with 2,2'-bipyridine to stabilize the first copper plating solution, reduce the porosity of the first copper layer, and improve the surface finish of the first copper layer.

[0011] The first copper layer is immersed in a silane coupling agent. The siloxy group (Si-O-) in the silane coupling agent hydrolyzes with the metallic copper on the surface of the first copper layer to form a chemical bond. The organic functional group (such as epoxy group, amino group) at the other end combines with the second copper plating solution to achieve a "molecular bridge" connection at the inorganic-organic interface, thereby enhancing the chemical bonding strength between the second copper layer and the first copper layer and reducing the risk of peeling due to physical stress or environmental corrosion. At the same time, the use of a silane coupling agent can reduce the surface energy of the first copper layer, making it easier to wet with the second copper plating solution, reducing interface defects (such as bubbles and microcracks), thereby improving adhesion and uniformity. In the second copper plating solution, copper sulfate provides the copper source, and sodium methanesulfonate serves as the conductive salt. Sodium methanesulfonate is completely ionized in water to generate Na + and CH 3 SO 3 - ions, significantly improve the conductivity of the plating solution, improve the coating coverage in low current density areas such as deep holes and grooves, 3 SO 3 - Ions can be adsorbed on the cathode surface to form a dynamic barrier, increase the hydrogen evolution overpotential, thereby reducing hydrogen generation and avoiding loose coating caused by hydrogen retention. 3 SO 3 - Can also be used with Cu 2+ Formation of [Cu(CH 3 SO 3 )] + , moderately slowing down Cu 2+ The reduction rate of potassium perfluorooctane sulfonate is reduced, which promotes grain refinement. The perfluorooctane chain has extremely low surface energy, and its sulfonic acid group (-SO 3 - ) is directional adsorbed on the surface of the first copper layer, reducing the surface tension of the second copper plating solution, allowing the solution to quickly spread into the micropores or grooves, improving the uniformity of the second copper plating solution coverage, and at the same time forming a monolayer on the cathode surface to block the retention of hydrogen bubbles. Polyaspartic acid forms a stable chelate with Cu²⁺ through carboxyl and amino functional groups, inhibiting the hydrolysis and abnormal deposition of free copper ions, extending the service life of the plating solution, forming a physical barrier film on the surface of the coating, and inhibiting Cl - , O 2It can prevent the penetration of corrosive media such as copper and slow down the oxidation reaction of copper. It can also reduce the risk of spontaneous decomposition of the second copper plating and maintain the uniform dispersion of metal ions during the electroplating process. As an amphoteric surfactant, sulfobetaine can reduce the surface tension of the second copper plating solution, enhance the wettability of the electrode / second copper plating solution interface, reduce the defects of the second copper layer caused by bubble adhesion, and improve the uniformity of copper deposition by adsorbing on the electrode surface to form a uniform electric field distribution. It preferentially adsorbs on the microscopic protrusions of the substrate to inhibit local over-deposition, achieve surface leveling of the second copper layer, and enhance brightness. The synergistic effect of sulfobetaine and polyaspartic acid can further refine the grains and reduce the roughness of the second copper layer.

[0012] Chemical copper plating can achieve full coverage of the wire rod surface with many grooves and microcracks after drawing through self-catalytic reaction. The chemical copper plating layer as the base layer can ensure the uniform growth of the subsequent electroplated copper layer, avoid electroplating leakage caused by uneven current distribution, and form a uniform copper layer. The electroplated copper can achieve rapid thickening on the basis of the chemical copper thin layer. The electroplated copper layer further enhances the surface hardness and wear resistance on the basis of the chemical copper layer, prolongs the service life of the workpiece in a friction environment, improves the arc stability and wire feeding stability of the gas shielded welding wire, and avoids a large amount of spatter.‌ Optionally, the preparation method of the first welding wire is: drawing the wire rod to a diameter of 1.0-1.2 mm and a surface roughness of Ra≤0.6 μm, then using a neutral enzyme cleaner to clean the wire rod for 10-15 minutes at a temperature of 55-60°C and a pH of 7.0-7.5 to remove surface grease, and then using a mixed solution of citric acid and hydrogen peroxide in a mass ratio of 2-3:1 to acidify the wire rod under ultrasonic assistance, and finally using Pd-Sn colloid catalysis to obtain the first welding wire.

[0013] In the above technical solution, Pd-Sn colloid is adsorbed on the surface of the wire rod through van der Waals force to form high-density catalytic sites, which promotes the grain refinement of the first copper layer formed by chemical copper plating, significantly reduces the porosity, and can also accelerate the speed of chemical copper plating.

[0014] Optionally, the preparation process of the high-strength gas shielded welding wire also includes sealing and post-processing steps, and the sealing and post-processing steps are: placing the high-strength gas shielded welding wire in a sealing solution and soaking it at a temperature of 75-80°C for 2-3 minutes to quickly form a film, and then passivating and drying; the sealing solution includes acrylic emulsion and aziridine in a mass ratio of 10-20:1.

[0015] In the above technical solution, the acrylic emulsion and aziridine in the sealing solution are cross-linked to form an acrylic resin polymer, which forms a film on the surface of the copper layer to seal the pores. The carboxyl groups contained in the resin can coordinate with metal ions to enhance the adsorption force with the copper layer.

[0016] Optionally, the first copper plating solution comprises 30-40 parts by weight of a first composite complexing agent, wherein the first composite complexing agent comprises sodium citrate and potassium sodium tartrate in a mass ratio of 1-1.5:1.

[0017] In the above technical solution, sodium citrate can react with Cu through carboxyl and hydroxyl groups. 2+ Forming a stable complex [Cu(C 6 H 5 O 7 )] 3- , prevent copper ions from hydrolyzing or precipitating, ensure the uniform release of copper ions in the plating solution, and improve the deep plating ability. At the same time, sodium citrate is environmentally friendly and non-toxic. Potassium sodium tartrate combines with copper ions in alkaline solutions to form soluble complexes, which prevent copper ions from forming copper hydroxide precipitation and maintain the stability of the plating solution. Optionally, the first copper plating solution comprises 0.1-0.2 parts by weight of carboxylated carbon nanotubes, wherein the carboxylated carbon nanotubes are obtained by oxidizing carbon nanotubes in a mixture of concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 3:1.

[0018] In the above technical scheme, the carboxyl functional groups (-COOH) introduced on the surface of the carboxylated carbon nanotubes significantly enhance the hydrophilicity of the first copper plating solution, making it easier to evenly disperse in the first copper plating solution, avoiding the problem of uneven coating caused by hydrophobic agglomeration. The carboxyl functional groups maintain the stable suspension state of the carbon nanotubes in the plating solution through electrostatic repulsion, ensuring their uniform distribution in the coating. The active sites on the surface of the carboxylated carbon nanotubes can form coordination bonds with copper ions, promote the chemical bonding between the copper coating and the carbon nanotubes, and enhance the overall mechanical properties of the coating. By coating the surface of the carbon nanotubes with a copper layer through chemical copper plating, the wettability of the carbon nanotubes and the metal matrix can be improved, the interface defects can be reduced, and the bonding strength of the coating can be improved. As a conductive enhancer, the carboxylated carbon nanotubes can construct a three-dimensional conductive network in the plating solution, accelerate the copper ion reduction process, and improve the deposition rate and density of the coating. The carboxyl functional groups can serve as active sites to adsorb copper ions, optimize the distribution of copper ions in the plating solution, inhibit the agglomeration of copper particles, and refine the grain size of the coating. ‌‌‌ Optionally, the second copper plating solution comprises 15-25 parts by weight of a second composite complexing agent, wherein the second composite complexing agent comprises sodium gluconate and aminosulfonic acid in a mass ratio of 1.2-1.5:1.

[0019] In the above technical solution, sodium gluconate can be combined with Cu 2+ Forming a stable [Cu(C 6 H 11 O 7 )] 2-Complexes can prevent copper ions from hydrolyzing or abnormally depositing in the second copper plating solution, maintain the uniformity of the second copper plating solution, and adjust the pH value of the second copper plating solution to maintain the acid-base environment of the electroplating reaction, improve the uniformity of the crystallization of the coating, maintain corrosion inhibition performance under high temperature conditions, reduce the porosity of the coating, and improve corrosion resistance. Aminosulfonic acid can promote the grain refinement of the second copper layer, form a dense and ductile copper coating, reduce the internal stress of the coating, adsorb on the metal surface in the second copper plating solution, inhibit dendrite growth, and improve the uniformity and bonding strength of the second copper layer. Sodium gluconate can also synergistically enhance the deep plating ability of the second copper plating solution with sodium methanesulfonate, thereby improving the uniformity of the thickness of the second copper layer.

[0020] Optionally, the second copper plating solution comprises 0.1-0.2 parts by mass of nitrogen-doped carbon quantum dots, and the nitrogen-doped carbon quantum dots are prepared by hydrothermal reaction using citric acid as a carbon source and ethylenediamine as a nitrogen source.

[0021] In the above technical solution, the surface of nitrogen-doped carbon quantum dots is rich in amino groups (-NH 2 ) and carboxyl (-COOH) functional groups, which can react with Cu 2+ It forms a stable coordination complex, inhibits the hydrolysis or abnormal deposition of free copper ions, and maintains the uniformity of the second copper plating solution. The high specific surface area and hydrophilicity of nitrogen-doped carbon quantum dots can adsorb copper particles, prevent agglomeration, improve the dispersion stability of the plating solution, and reduce the porosity of the coating. The nitrogen-doped characteristics give it electrocatalytic activity, which can reduce the activation energy of the copper ion reduction reaction, accelerate the electrochemical deposition rate, and improve the electroplating efficiency. Through the optimization of interfacial charge transfer, it promotes the uniform nucleation of copper crystal nuclei to form a dense coating. The nitrogen-doped carbon quantum dots adsorbed on the electrode surface can serve as nucleation sites to inhibit the coarsening of copper grains and improve the hardness and wear resistance of the coating. The internal stress of the coating is reduced through surface adsorption, reducing the risk of cracks and warping. In a second aspect, the present invention provides a high-strength gas shielded welding wire, which includes a wire rod and a copper plating layer, and the copper plating layer includes a first copper layer and a second copper layer.

[0022] Optionally, the thickness of the first copper layer is 1-3 μm, and the thickness of the second copper layer is 5-15 μm.

[0023] In the third aspect, the present invention provides a high-strength gas shielded welding wire prepared by a preparation process thereof and its application in the petrochemical industry, shipbuilding industry, aerospace industry, food machinery and medical equipment manufacturing industry, and energy storage and transportation equipment industry.

[0024] In summary, the present invention includes at least one of the following beneficial technical effects: By immersing the first copper layer in a silane coupling agent, the siloxy group (Si-O-) in the silane coupling agent hydrolyzes with the metallic copper on the surface of the first copper layer to form a chemical bond, and the organic functional group (such as epoxy group, amino group) at the other end combines with the second copper plating solution to achieve a "molecular bridge" connection at the inorganic-organic interface, thereby enhancing the chemical bonding strength between the second copper layer and the first copper layer and reducing the risk of peeling due to physical stress or environmental corrosion. At the same time, the use of a silane coupling agent treatment can reduce the surface energy of the first copper layer, making it easier to wet with the second copper plating solution, reducing interface defects, and thus improving the adhesion and uniformity of the coating.

[0025] By combining the chemical copper plating process with the electroplating copper process, the chemical copper plating can achieve full coverage of the wire rod surface with many surface grooves and microcracks after drawing through self-catalytic reaction. The chemical copper plating layer as the bottom layer can ensure the uniform growth of the subsequent electroplated copper layer, avoid electroplating leakage caused by uneven current distribution, and form a uniform copper layer. The electroplated copper achieves rapid thickening on the basis of the chemical copper thin layer. The electroplated copper layer further enhances the surface hardness and wear resistance on the basis of the chemical copper layer, prolongs the service life of the workpiece in the friction environment, improves the arc stability and wire feeding stability of the gas shielded welding wire, and avoids a large amount of spatter. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below with reference to the embodiments.

[0027] The materials used in the following examples can all be purchased from the market.

[0028] Example 1: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0029] S1. Prepare the first copper layer by chemical copper plating: put the first welding wire into the first copper plating solution and perform chemical electroplating for 5 minutes at a temperature of 55° C. and a rotation speed of 5 m / min to form a first copper layer on the surface of the first welding wire. After immersing the first copper layer in a silane coupling agent with a concentration of 1% for 5 minutes, the first copper layer is dried at a temperature of 60° C. to obtain a second welding wire; S2. Electroplating copper to prepare the second copper layer: Use the second copper plating solution to electroplate the second welding wire at a current density of 15A / dm 2 The copper is electroplated at a temperature of 45°C to form a second copper layer on the surface of the second welding wire to obtain a high-strength gas shielded welding wire #1.

[0030] In this embodiment, the first welding wire is obtained by removing oil from the surface of the wire rod and activating it. The silane coupling agent is KH-550, and in other embodiments, other silane coupling agents such as KH-560 may also be used.

[0031] In parts by mass, the first copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, and 0.08 parts of a stabilizer, wherein the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1; the second copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, and 0.3 parts of an additive, wherein the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0032] The high-strength gas shielded welding wire #1 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0033] Example 2: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0034] S1. Pretreatment: drawing the wire rod to a diameter of 1.0-1.2 mm and a surface roughness of Ra≤0.6 μm, then using a neutral enzyme cleaning agent to clean the wire rod for 15 min at a temperature of 60°C and a pH of 7.5 to remove surface grease, then using a mixed solution of citric acid and hydrogen peroxide in a mass ratio of 2-3:1 to acidify the wire rod under ultrasound assistance, and finally using Pd-Sn colloid catalysis to obtain a first welding wire; S2. Prepare the first copper layer by chemical copper plating: put the first welding wire into the first copper plating solution and perform chemical electroplating for 5 minutes at a temperature of 55° C. and a rotation speed of 5 m / min to form a first copper layer on the surface of the first welding wire. After immersing the first copper layer in a silane coupling agent with a concentration of 1% for 5 minutes, the first copper layer is dried at a temperature of 60° C. to obtain a second welding wire. S3, electroplating copper to prepare the second copper layer: using the second copper plating solution to the second welding wire at a current density of 15A / dm 2 The copper is electroplated at a temperature of 45°C to form a second copper layer on the surface of the second welding wire to obtain a high-strength gas shielded welding wire #2.

[0035] In this embodiment, the wire rod is a low alloy steel wire rod, and in other embodiments, the wire rod may also be a low carbon steel wire rod. The rest is the same as in Embodiment 1.

[0036] The high-strength gas shielded welding wire #2 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0037] Example 3: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0038] S1. Prepare the first copper layer by chemical copper plating: put the first welding wire into the first copper plating solution and perform chemical electroplating for 5 minutes at a temperature of 55° C. and a rotation speed of 5 m / min to form a first copper layer on the surface of the first welding wire. After immersing the first copper layer in a silane coupling agent with a concentration of 1% for 5 minutes, the first copper layer is dried at a temperature of 60° C. to obtain a second welding wire; S2. Electroplating copper to prepare the second copper layer: Use the second copper plating solution to electroplate the second welding wire at a current density of 15A / dm 2 , electroplating copper at a plating temperature of 45° C. to form a second copper layer on the surface of the second welding wire to obtain a third welding wire; S3, sealing and post-processing: the third welding wire is placed in a sealing solution and immersed at a temperature of 80° C. for 3 minutes to form a film quickly, and then passivated and dried to obtain the high-strength gas shielded welding wire #3.

[0039] In this embodiment, the first welding wire is obtained by performing surface degreasing and activation treatment on the wire rod. The sealing solution includes acrylic emulsion and aziridine in a mass ratio of 15:1. The rest is the same as in embodiment 1.

[0040] The high-strength gas shielded welding wire #3 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0041] Example 4: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0042] S1. Pretreatment: drawing the wire rod to a diameter of 1.0-1.2 mm and a surface roughness of Ra≤0.6 μm, then using a neutral enzyme cleaning agent to clean the wire rod for 15 min at a temperature of 60°C and a pH of 7.5 to remove surface grease, then using a mixed solution of citric acid and hydrogen peroxide in a mass ratio of 2-3:1 to acidify the wire rod under ultrasound assistance, and finally using Pd-Sn colloid catalysis to obtain a first welding wire; S2. Prepare the first copper layer by chemical copper plating: put the first welding wire into the first copper plating solution and perform chemical electroplating for 5 minutes at a temperature of 55° C. and a rotation speed of 5 m / min to form a first copper layer on the surface of the first welding wire. After immersing the first copper layer in a silane coupling agent with a concentration of 1% for 5 minutes, the first copper layer is dried at a temperature of 60° C. to obtain a second welding wire. S3, electroplating copper to prepare the second copper layer: using the second copper plating solution to the second welding wire at a current density of 15A / dm 2 , electroplating copper at a plating temperature of 45° C. to form a second copper layer on the surface of the second welding wire to obtain a third welding wire; S4, sealing and post-processing: the third welding wire is placed in a sealing solution and immersed at a temperature of 80° C. for 3 minutes to form a film quickly, and then passivated and dried to obtain the high-strength gas shielded welding wire #4.

[0043] In parts by mass, the first copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, and 0.08 parts of a stabilizer, wherein the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1; the second copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, and 0.3 parts of an additive, wherein the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution includes an acrylic emulsion and aziridine in a mass ratio of 15:1; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0044] The high-strength gas shielded welding wire #4 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0045] Example 5: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0046] The preparation process is the same as that of Example 4.

[0047] In parts by mass, the first copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, 0.08 parts of a stabilizer, and 30 parts of a first composite complexing agent, wherein the first composite complexing agent includes sodium citrate and potassium sodium tartrate in a mass ratio of 1.5:1, and the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1; the second copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, and 0.3 parts of an additive, wherein the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution includes an acrylic emulsion and aziridine in a mass ratio of 15:1; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0048] The high-strength gas shielded welding wire #5 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0049] Example 6: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0050] The preparation process is the same as that of Example 4.

[0051] In parts by mass, the first copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, 0.08 parts of a stabilizer, 30 parts of a first composite complexing agent, and 0.15 parts of carboxylated carbon nanotubes, wherein the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1, and the first composite complexing agent includes sodium citrate and potassium sodium tartrate in a mass ratio of 1.5:1; the second copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, and 0.3 parts of an additive, wherein the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution includes an acrylic emulsion and aziridine in a mass ratio of 15:1; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0052] The high-strength gas shielded welding wire #6 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0053] Example 7: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0054] The preparation process is the same as that of Example 4.

[0055] In parts by mass, the first copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, and 0.08 parts of a stabilizer, wherein the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1; the second copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, 0.3 parts of an additive, and 20 parts of a second composite complexing agent, wherein the second composite complexing agent includes sodium gluconate and aminosulfonic acid in a mass ratio of 1.3:1, and the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution includes an acrylic emulsion and aziridine in a mass ratio of 15:1; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0056] The high-strength gas shielded welding wire #7 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0057] Example 8: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0058] The preparation process is the same as that of Example 4.

[0059] In parts by mass, the first copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, and 0.08 parts of a stabilizer, wherein the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1; the second copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, 0.3 parts of an additive, 20 parts of a second composite complexing agent, and 0.1 parts of nitrogen-doped carbon quantum dots, wherein the second composite complexing agent includes sodium gluconate and aminosulfonic acid in a mass ratio of 1.3:1, and the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution includes an acrylic emulsion and aziridine in a mass ratio of 15:1; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0060] The high-strength gas shielded welding wire #8 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0061] Example 9: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0062] The preparation process is the same as that of Example 4.

[0063] In parts by mass, the first copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, 0.08 parts of a stabilizer, and 30 parts of a first composite complexing agent, wherein the first composite complexing agent includes sodium citrate and potassium sodium tartrate in a mass ratio of 1.5:1, and the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1; the second copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, 0.3 parts of an additive, and 20 parts of a second composite complexing agent, wherein the second composite complexing agent includes sodium gluconate and aminosulfonic acid in a mass ratio of 1.3:1, and the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution includes 15:1 acrylic emulsion and aziridine; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0064] The high-strength gas shielded welding wire #9 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0065] Example 10: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0066] The preparation process is the same as that of Example 4.

[0067] In parts by mass, the first copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, 0.08 parts of a stabilizer, and 30 parts of a first composite complexing agent, wherein the first composite complexing agent includes sodium citrate and potassium sodium tartrate in a mass ratio of 1.5:1, and the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1; the second copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, 0.3 parts of an additive, 20 parts of a second composite complexing agent, and 0.1 parts of nitrogen-doped carbon quantum dots, wherein the second composite complexing agent includes sodium gluconate and aminosulfonic acid in a mass ratio of 1.3:1, and the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution includes 15:1 acrylic emulsion and aziridine; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0068] The high-strength gas shielded welding wire #10 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0069] Example 11: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0070] The preparation process is the same as that of Example 4.

[0071] In parts by mass, the first copper plating solution comprises 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, 0.08 parts of a stabilizer, 30 parts of a first composite complexing agent, and 0.15 parts of carboxylated carbon nanotubes, wherein the stabilizer comprises 2,2'-bipyridine and thiourea in a mass ratio of 2:1, and the first composite complexing agent comprises sodium citrate and potassium sodium tartrate in a mass ratio of 1.5:1; the second copper plating solution comprises 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, 0.3 parts of an additive, and 20 parts of a second composite complexing agent, wherein the second composite complexing agent comprises sodium gluconate and aminosulfonic acid in a mass ratio of 1.3:1, and the additive comprises polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution comprises 15:1 acrylic emulsion and aziridine; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0072] The high-strength gas shielded welding wire #11 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0073] Example 12: A preparation process of a high-strength gas shielded welding wire and the high-strength gas shielded welding wire.

[0074] The preparation process is the same as that of Example 4.

[0075] The first copper plating solution comprises, by weight, 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, 0.08 parts of a stabilizer, 30 parts of a first composite complexing agent, and 0.15 parts of a carboxylated carbon nanotube, wherein the stabilizer comprises 2,2'-bipyridine and thiourea in a mass ratio of 2:1, and the first composite complexing agent comprises sodium citrate and potassium sodium tartrate in a mass ratio of 1.5:1; the second copper plating solution comprises: The solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, 0.3 parts of additives, 20 parts of a second composite complexing agent, and 0.1 parts of nitrogen-doped carbon quantum dots, wherein the second composite complexing agent includes sodium gluconate and aminosulfonic acid in a mass ratio of 1.3:1, and the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1; the sealing solution includes an acrylic emulsion and aziridine in a mass ratio of 15:1; the mass ratio of the first copper plating solution to the second copper plating solution is 1:2.

[0076] The high-strength gas shielded welding wire #12 includes a wire rod and a copper-plated layer, wherein the copper-plated layer includes a first copper layer with a thickness of 1.5 μm and a second copper layer with a thickness of 10 μm.

[0077] Comparative Example 1: This comparative example provides a comparison of a preparation process of a high-strength gas shielded welding wire and a comparison of a high-strength gas shielded welding wire D1, which is the same as Example 4, except that step S2, a first copper layer is prepared by chemical copper plating: the first welding wire is placed in a first copper plating solution and chemically electroplated for 3-5 minutes at a temperature of 54-56°C and a rotation speed of 3-5m / min, forming a first copper layer on the surface of the first welding wire to obtain a second welding wire.

[0078] Comparative Example 2: This comparative example provides a comparison of a preparation process of a high-strength gas shielded welding wire and a comparison of a high-strength gas shielded welding wire D2, which is the same as Example 4, except that step S4, post-treatment: the third welding wire is passivated and dried to obtain the high-strength gas shielded welding wire D2.

[0079] Comparative Example 3: This comparative example provides a preparation process for a high-strength gas shielded welding wire and a high-strength gas shielded welding wire D3 for comparison. The preparation process includes the following steps: S1. Pretreatment: drawing the wire rod to a diameter of 1.0-1.2 mm and a surface roughness of Ra≤0.6 μm, then using a neutral enzyme cleaning agent to clean the wire rod for 15 min at a temperature of 60°C and a pH of 7.5 to remove surface grease, then using a mixed solution of citric acid and hydrogen peroxide in a mass ratio of 2-3:1 to acidify the wire rod under ultrasound assistance, and finally using Pd-Sn colloid catalysis to obtain a first welding wire; S2, preparing a copper layer by chemical copper plating: placing the first welding wire in a copper plating solution and chemically electroplating for 5 minutes at a temperature of 55° C. and a rotation speed of 5 m / min to form a copper layer on the surface of the first welding wire, thereby obtaining a second welding wire; S3, sealing and post-processing: the second welding wire is placed in a sealing solution and immersed at a temperature of 80° C. for 3 minutes to form a film quickly, and then passivated and dried to obtain the high-strength gas shielded welding wire D3.

[0080] The copper plating solution includes 15 parts of copper sulfate, 30 parts of sodium hypophosphite, 15 parts of sodium hydroxide, 0.03 parts of sodium dodecylbenzene sulfonate, and 0.08 parts of a stabilizer, wherein the stabilizer includes 2,2'-bipyridine and thiourea in a mass ratio of 2:1, and the rest is the same as in Example 4.

[0081] Comparative Example 4: This comparative example provides a preparation process for a high-strength gas shielded welding wire and a high-strength gas shielded welding wire D4 for comparison. The preparation process includes the following steps: S1. Pretreatment: drawing the wire rod to a diameter of 1.0-1.2 mm and a surface roughness of Ra≤0.6 μm, then using a neutral enzyme cleaning agent to clean the wire rod for 15 min at a temperature of 60°C and a pH of 7.5 to remove surface grease, then using a mixed solution of citric acid and hydrogen peroxide in a mass ratio of 2-3:1 to acidify the wire rod under ultrasound assistance, and finally using Pd-Sn colloid catalysis to obtain a first welding wire; S2. Preparation of copper layer by electroplating copper: Use copper plating solution to treat the first welding wire at a current density of 15A / dm 2 , electroplating copper at a temperature of 45° C. to form a copper layer, thereby obtaining a second welding wire; S3, sealing and post-processing: the second welding wire is placed in a sealing solution and immersed at a temperature of 80° C. for 3 minutes to form a film quickly, and then passivated and dried to obtain the high-strength gas shielded welding wire D4.

[0082] The copper plating solution includes 40 parts of copper sulfate, 80 parts of sodium methane sulfonate, 20 parts of boric acid-triethanolamine buffer, 0.3 parts of potassium perfluorooctane sulfonate, and 0.3 parts of an additive, wherein the additive includes polyaspartic acid and thiobetaine in a mass ratio of 1.5:1, and the rest is the same as Example 4.

[0083] Comparative Example 5: This comparative example provides a preparation process for comparing a high-strength gas shielded welding wire and a comparative high-strength gas shielded welding wire D5, which is the same as the preparation process of Example 4, except that: 0.03 parts of sodium dodecylbenzene sulfonate are missing in the first copper plating solution.

[0084] Comparative Example 6: This comparative example provides a preparation process for a high-strength gas shielded welding wire and a comparison high-strength gas shielded welding wire D6, which is the same as the preparation process of Example 4, except that: 0.08 parts of stabilizer are missing in the first copper plating solution.

[0085] Comparative Example 7: This comparative example provides a preparation process for a high-strength gas shielded welding wire and a comparative high-strength gas shielded welding wire D7, which is the same as the preparation process of Example 4, except that: 0.3 parts of potassium perfluorooctane sulfonate are missing in the second copper plating solution.

[0086] Comparative Example 8: This comparative example provides a preparation process for a high-strength gas shielded welding wire and a comparison high-strength gas shielded welding wire D8, which is the same as the preparation process of Example 4, except that sodium chloride is used instead of sodium methanesulfonate in the second copper plating solution.

[0087] Comparative Example 9: This comparative example provides a comparison of the preparation process of a high-strength gas shielded welding wire and a comparison of the high-strength gas shielded welding wire D9, which is the same as the preparation process of Example 4, except that a mixture of 2-thiazoline polydisulfide propane sulfonate and sodium N,N-dimethyldithioamide propane sulfonate is used in the second copper plating solution instead of polyaspartic acid and thiobetaine.

[0088] Various welding tests were performed on the non-copper-plated welding wires #1-#12 of Examples 1-12 and the comparative non-copper-plated welding wires D1-D9 of Comparative Examples 1-9 as shown in Table 1. The welding performance is shown in Table 2, including salt spray test, arc stability test, welding spatter test, wire feeding performance test, copper layer adhesion test, and copper layer bonding test. The salt spray test was carried out for 96 hours according to ISO9277 standard to observe the corrosion of the copper plating surface. The copper layer adhesion test adopted the cross-cutting method. The specific test steps were as follows: fix the tested welding wire, use a cross-cutting knife with a tooth spacing of 1 mm to cut the coating at a 90° vertical angle to form a 10×10 grid (a total of 100 squares), and the incision must penetrate the copper layer to the substrate wire rod. Attach the tape tightly to the grid area, press the tape with an eraser to eliminate bubbles and enhance adhesion. After standing for 3 to 5 minutes, quickly tear off the tape at a 90° angle to avoid tilting or shaking. Use a magnifying glass or microscope to observe the grid area and count the copper layer shedding area (%). The copper layer bonding test adopted the tensile method (ASTM B571)), the specific test steps are to bond the test wire to the steel column with epoxy resin, and after curing, use a tensile testing machine to vertically stretch it until the coating is peeled off, and then calculate the bonding strength by the formula: bonding strength = maximum tension (N) / copper plating area (mm).

[0089] Table 1

[0090] Table 2

[0091] It can be seen from the test data in Table 2 that compared with Examples 2-4, Example 1 adds a pretreatment step in Example 2, adds a sealing and post-treatment step in Example 3, and adds a pretreatment, sealing and post-treatment step in Example 4. The high-strength gas shielded welding wires obtained in Examples 2-4 have better performance than Example 1, especially Example 4, which has excellent arc stability and wire feedability, low spatter rate, high tensile strength, small copper layer detachment area and copper layer corrosion area, large bonding force, and stable overall performance.

[0092] Compared with Example 4, in Example 5, the first copper plating solution in Example 5 is added with the first composite complexing agent, and in Example 7, the second copper plating solution in Example 7 is added with the second composite complexing agent, and the various properties of the obtained high-strength gas shielded welding wire are higher than the various properties of the high-strength gas shielded welding wire obtained in Example 4. Compared with Example 6, in Example 11, the second copper plating solution in Example 6 is added with the second composite complexing agent, and the various properties of the obtained high-strength gas shielded welding wire are better than those in Example 6. Compared with Example 5 and Example 7, in Example 9, the first copper plating solution in Example 5 is added with the first composite complexing agent, and the second copper plating solution in Example 7 is added with the second composite complexing agent, and the various properties of the obtained high-strength gas shielded welding wire are better than those in Example 5 and Example 7. That is because the sodium citrate in the first composite complex can react with Cu through carboxyl and hydroxyl groups. 2+ Forming a stable complex [Cu(C 6 H 5 O 7 )] 3- , prevent copper ions from hydrolyzing or precipitating, ensure the uniform release of copper ions in the plating solution, and improve the deep plating ability. At the same time, sodium citrate is environmentally friendly and non-toxic. Potassium sodium tartrate combines with copper ions in alkaline solution to form a soluble complex, which prevents copper ions from forming copper hydroxide precipitation and maintains the stability of the plating solution. The sodium gluconate in the second complex can react with Cu 2+ Forming a stable [Cu(C 6 H 11 O 7 )] 2-The complex prevents the copper ions from hydrolyzing or abnormally depositing in the second copper plating solution, maintains the uniformity of the second copper plating solution, and can also adjust the pH value of the second copper plating solution, maintain the acid-base environment of the electroplating reaction, improve the uniformity of the coating crystallization, maintain the corrosion inhibition performance under high temperature conditions, reduce the porosity of the coating, and improve the corrosion resistance. Aminosulfonic acid can promote the grain refinement of the second copper layer, form a dense and ductile copper coating, reduce the internal stress of the coating, adsorb on the metal surface in the second copper plating solution, inhibit the growth of dendrites, and improve the uniformity and bonding strength of the second copper layer.

[0093] Example 6 Compared with Example 5, carboxylated carbon nanotubes are added to the first copper plating solution, and the various properties of the obtained high-strength gas shielded welding wire are better than those of Example 5. The reason is that the carboxyl functional groups (-COOH) introduced on the surface of the carboxylated carbon nanotubes significantly enhance the hydrophilicity of the first copper plating solution, making it easier to disperse evenly in the first copper plating solution, avoiding the problem of uneven coating caused by hydrophobic agglomeration. The carboxyl functional groups maintain the stable suspension state of the carbon nanotubes in the plating solution through electrostatic repulsion, ensuring that they are evenly distributed in the coating. The active sites on the surface of the carboxylated carbon nanotubes can form coordination bonds with copper ions, promote the chemical bonding of the copper coating and the carbon nanotubes, and enhance the overall mechanical properties of the coating. By coating the surface of the carbon nanotubes with a copper layer through chemical copper plating, the wettability of the carbon nanotubes and the metal matrix can be improved, the interface defects can be reduced, and the bonding strength of the coating can be improved. As a conductive enhancer, the carboxylated carbon nanotubes can construct a three-dimensional conductive network in the plating solution, accelerate the reduction process of copper ions, and improve the deposition rate and density of the coating. The carboxyl functional group can serve as an active site to adsorb copper ions, optimize the distribution of copper ions in the plating solution, inhibit the agglomeration of copper particles, and refine the grain size of the coating.

[0094] Compared with Example 7, Example 10 compared with Example 9, nitrogen-doped carbon quantum dots were added to the second copper plating solution. The various properties of the high-strength gas shielded welding wire obtained in Example 8 were better than those in Example 7, and the various properties of the high-strength gas shielded welding wire obtained in Example 10 were better than those in Example 9. This is because the surface of the nitrogen-doped carbon quantum dots is rich in amino groups (-NH 2 ) and carboxyl (-COOH) functional groups, which can react with Cu 2+It forms a stable coordination complex, inhibits the hydrolysis or abnormal deposition of free copper ions, and maintains the uniformity of the second copper plating solution. The high specific surface area and hydrophilicity of nitrogen-doped carbon quantum dots can adsorb copper particles, prevent agglomeration, improve the dispersion stability of the plating solution, and reduce the porosity of the coating. The nitrogen-doped characteristics give it electrocatalytic activity, which can reduce the activation energy of the copper ion reduction reaction, accelerate the electrochemical deposition rate, and improve the electroplating efficiency. Through the optimization of interfacial charge transfer, it promotes the uniform nucleation of copper crystal nuclei to form a dense coating. The nitrogen-doped carbon quantum dots adsorbed on the electrode surface can serve as nucleation sites to inhibit the coarsening of copper grains and improve the hardness and wear resistance of the coating. The internal stress of the coating is reduced through surface adsorption, reducing the risk of cracks and warping. Compared with Example 4, Example 12 adds a first composite complexing agent and carboxylated carbon nanotubes to the first copper plating solution, and adds a second composite complexing agent and nitrogen-doped carbon quantum dots to the second copper plating solution. The obtained high-strength gas shielded welding wire has better performance than Example 4, especially the overall corrosion resistance of high-strength gas shielded welding wire #12, the adhesion and uniformity of the copper layer are much better than high-strength gas shielded welding wire #4.

[0095] Compared with Example 4, in Comparative Example 1, the first copper layer was not immersed in a silane coupling agent with a concentration of 1%. The performance of the obtained comparative high-strength gas shielded welding wire was inferior to that of the high-strength gas shielded welding wire in Example 4. This is because the first copper layer was immersed in the silane coupling agent, and the siloxy group (Si-O-) in the silane coupling agent hydrolyzed with the metallic copper on the surface of the first copper layer to form a chemical bond, and the organic functional group (such as epoxy group, amino group) at the other end combined with the second copper plating solution to achieve a "molecular bridge" connection at the inorganic-organic interface, thereby enhancing the chemical bonding strength between the second copper layer and the first copper layer and reducing the risk of peeling due to physical stress or environmental corrosion. At the same time, the use of silane coupling agent treatment can reduce the surface energy of the first copper layer, making it easier to wet with the second copper plating solution, reducing interface defects (such as bubbles and microcracks), thereby improving adhesion and uniformity. Compared with Example 4, Comparative Example 2 does not put the third welding wire into the sealing solution for rapid film formation. The performance of the high-strength gas shielded welding wire is inferior to that of the high-strength gas shielded welding wire of Example 4. This is because the acrylic emulsion and aziridine in the sealing solution are cross-linked to form an acrylic resin polymer, and the polymer forms a film on the surface of the copper layer to seal the pores. The carboxyl groups contained in the resin can coordinate with metal ions to enhance the adsorption force with the copper layer.

[0096] Compared with Example 4, Comparative Example 3 only uses chemical copper plating, and compared with Example 4, Comparative Example 4 only uses electroplating. The performance of the high-strength gas shielded welding wire is far inferior to that of the high-strength gas shielded welding wire of Example 4. This is because chemical copper plating can achieve full coverage of the wire rod surface with many surface grooves and microcracks after drawing through self-catalytic reaction. The chemical copper plating layer as the bottom layer can ensure the uniform growth of the subsequent electroplated copper layer, avoid leakage caused by uneven current distribution, and form a uniform copper layer. The electroplated copper achieves rapid thickening on the basis of the chemical copper thin layer. The electroplated copper layer further enhances the surface hardness and wear resistance on the basis of the chemical copper layer, prolongs the service life of the workpiece in the friction environment, improves the arc stability and wire feeding stability of the gas shielded welding wire, and avoids a lot of spatter.‌ Comparative Examples 5-9 Compared with Example 4, the first copper plating solution in Comparative Example 3 lacks sodium dodecylbenzene sulfonate; the first copper plating solution in Comparative Example 4 lacks a stabilizer; the second copper plating solution in Comparative Example 5 lacks potassium perfluorooctane sulfonate; sodium chloride replaces sodium methane sulfonate in the second copper plating solution in Comparative Example 6; the mixture of 2-thiazoline polydisulfide propane sulfonate and sodium N,N-dimethyldithioformamide propane sulfonate in the second copper plating solution in Comparative Example 7 replaces polyaspartic acid and thiobetaine. The various properties of the high-strength gas shielded welding wire are not as good as those of Example 4. It can be seen that the missing or replaced materials cannot play a role in the high-strength gas shielded welding wire, but will reduce the role of the high-strength gas shielded welding wire. Therefore, each component cannot be arbitrarily replaced by other materials.

[0097] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A preparation process of high-strength gas shielded welding wire, characterized in that: The preparation process of the high-strength gas shielded welding wire comprises the following steps: The first copper layer is prepared by chemical copper plating: the first welding wire is placed in the first copper plating solution and chemically electroplated for 3-5 minutes at a temperature of 54-56° C. and a rotation speed of 3-5 m / min to form a first copper layer on the surface of the first welding wire, the first copper layer is immersed in a silane coupling agent with a concentration of 1% for 3-5 minutes, and then dried at a temperature of 55-60° C. to obtain a second welding wire; Preparation of the second copper layer by electroplating copper: Use the second copper plating solution to electroplate the second welding wire at a current density of 13-15A / dm 2 , electroplating copper at a temperature of 40-45° C. to form a second copper layer on the surface of the second welding wire to obtain the high-strength gas shielded welding wire; The first copper plating solution comprises, by mass, 15-20 parts of copper sulfate, 30-40 parts of sodium hypophosphite, 15-18 parts of sodium hydroxide, 0.01-0.05 parts of sodium dodecylbenzene sulfonate, and 0.05-0.1 parts of a stabilizer, wherein the stabilizer comprises 2,2'-bipyridine and thiourea in a mass ratio of 2-3:1; the second copper plating solution comprises 30-50 parts of copper sulfate, 60-100 parts of sodium methane sulfonate, 15-25 parts of boric acid-triethanolamine buffer, 0.1-0.5 parts of potassium perfluorooctane sulfonate, and 0.5-1 parts of an additive, wherein the additive comprises polyaspartic acid and thiobetaine in a mass ratio of 1-1.5:1; The mass ratio of the first copper plating solution to the second copper plating solution is 1:1.5-2.

2. The preparation process of a high-strength gas shielded welding wire according to claim 1, characterized in that: The preparation method of the first welding wire is: drawing the wire rod to a diameter of 1.0-1.2 mm and a surface roughness of Ra≤0.6 μm, then using a neutral enzyme cleaner to clean the wire rod for 10-15 minutes at a temperature of 55-60°C and a pH of 7.0-7.5 to remove surface grease, then using a mixed solution of citric acid and hydrogen peroxide in a mass ratio of 2-3:1 to acidify the wire rod under ultrasonic assistance, and finally using Pd-Sn colloid catalysis to obtain the first welding wire.

3. The preparation process of a high-strength gas shielded welding wire according to claim 1 or 2, characterized in that: The preparation process of the high-strength gas shielded welding wire also includes sealing and post-processing steps, which are: placing the high-strength gas shielded welding wire in a sealing solution and soaking it at a temperature of 75-80°C for 2-3 minutes to quickly form a film, and then passivating and drying; the sealing solution includes acrylic emulsion and aziridine in a mass ratio of 10-20:

1.

4. A process for preparing a high-strength gas shielded welding wire according to claim 1 or 2, characterized in that: The first copper plating solution comprises 30-40 parts by weight of a first composite complexing agent, wherein the first composite complexing agent comprises sodium citrate and potassium sodium tartrate in a mass ratio of 1-1.5:

1.

5. The preparation process of a high-strength gas shielded welding wire according to claim 4, characterized in that: The first copper plating solution also includes 0.1-0.2 parts by mass of carboxylated carbon nanotubes, wherein the carboxylated carbon nanotubes are obtained by oxidizing carbon nanotubes in a mixed solution of concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 3:

1.

6. A process for preparing a high-strength gas shielded welding wire according to any one of claims 1 or 2, characterized in that: The second copper plating solution comprises 15-25 parts by weight of a second composite complexing agent, and the second composite complexing agent comprises sodium gluconate and aminosulfonic acid in a mass ratio of 1.2-1.5:

1.

7. The process for preparing a high-strength gas shielded welding wire according to claim 6, characterized in that: The second copper plating solution also includes 0.1-0.2 parts by mass of nitrogen-doped carbon quantum dots, which are prepared by hydrothermal reaction using citric acid as a carbon source and ethylenediamine as a nitrogen source.

8. A high-strength gas shielded welding wire prepared by the preparation process of the high-strength gas shielded welding wire according to any one of claims 1 to 7, characterized in that: The high-strength gas shielded welding wire comprises a wire rod and a copper-plated layer, and the copper-plated layer comprises a first copper layer and a second copper layer.

9. A high-strength gas shielded welding wire according to claim 8, characterized in that: The thickness of the first copper layer is 1-3 μm, and the thickness of the second copper layer is 5-15 μm.

10. Application of a high-strength gas shielded welding wire in the aerospace industry, automobile manufacturing industry, food machinery and medical equipment manufacturing industry, and in robot welding scenarios, characterized in that: A high-strength gas shielded welding wire prepared by the method for preparing a high-strength gas shielded welding wire as described in any one of claims 1 to 7, or a high-strength gas shielded welding wire as described in any one of claims 8 to 9.

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