A method of manufacturing an alloy steel welding wire by a cladding process

Abstract

The application provides a method for manufacturing alloy steel welding wire by a plating method, and belongs to the field of metal material welding materials, and comprises the following steps: analyzing the welding wire to obtain the original content of elements in the welding wire and giving a designed value of the alloy content of the welding wire to determine the alloy content in the plating layer; determining the preliminary thickness of the alloy plating layer of the welding wire; plating the plating layer on the surface of the welding wire according to the preliminary thickness; analyzing and testing to obtain the alloy content of the plating layer, comparing the alloy content of the plating layer with the designed value of the alloy content of the welding wire to obtain the adjustment coefficient of the alloy plating layer; determining the adjusted thickness of the alloy plating layer; and re-plating the original welding wire according to the adjusted thickness of the alloy plating layer. The application changes the thickness of the plating layer to increase the content of certain alloy elements of the existing welding wire, and meets the welding requirements of special materials and structures. The plating method is flexible, the thickness is easy to control, and the method has the advantages of low investment, green environmental protection, convenient component adjustment, low cost and short production cycle.

Description

Technical Field

[0001] This invention belongs to the field of metal welding materials technology, and specifically relates to a method for manufacturing alloy steel welding wire using a coating method. Background Technology

[0002] Welding is an essential joining method in the engineering application of steel materials, widely used in various industrial sectors and civil facilities. The manufacturing industry requires a large amount of high-performance welding materials. Solid welding wire, as one of the main types of welding materials, is widely used in many industries such as automobiles, shipbuilding, petroleum, and construction. With the widespread application of automated, semi-automated, and intelligent welding technologies, especially in the emerging additive manufacturing industry, the demand for solid welding wire will continue to grow rapidly.

[0003] Solid welding wire can be divided into two types: copper-plated and copper-free. Copper-plated welding wire involves plating a layer of copper onto the surface of the treated wire to enhance its rust resistance, improve conductivity, and reduce feeding friction. After decades of development, copper-plated welding wire technology and equipment are very mature, and copper-plated welding wire is widely used due to its superior conductivity, rust resistance, and lubrication properties, holding a market share of over 90%. Copper-free welding wire eliminates the copper plating process, using a surface coating to replace the original copper plating layer. This allows the welding wire to meet welding process requirements in terms of conductivity, rust resistance, and lubrication, and it only gained widespread recognition in the early 21st century. Copper-free welding wire is energy-saving and environmentally friendly during production and use, greatly improving the working environment. However, compared to copper-plated welding wire, domestic copper-free welding wire technology and equipment are not yet mature, exhibiting quality defects in conductivity, rust resistance, and lubrication, affecting production efficiency. Imported welding wire is expensive, increasing production costs; therefore, copper-free welding wire has not been widely accepted.

[0004] Steel materials rely on the addition of alloying elements such as nickel (Ni), chromium (Cr), and molybdenum (Mo) to iron to improve their strength and toughness, and welding wire is no exception. Traditional solid welding wire is alloyed by adding alloying elements through high-temperature smelting in a smelting furnace. However, the smelting process for welding wire involves large quantities, high costs, and long cycles.

[0005] In current welding research and production processes, difficulties are frequently encountered in selecting and procuring welding wire. For example, due to the limited variety of standardized welding wires, existing welding wires on the market cannot meet the strength, toughness, and other performance requirements of specific materials and applications. This is especially true for welding small quantities of special materials and emerging additive manufacturing (3D printing), which requires welding wires with special alloy compositions and multiple alloy elements in small batches. Commercially available welding wires are not readily available. Manufacturing them using traditional smelting and drawing processes is costly and time-consuming, severely impacting the progress of research and engineering projects. Coating (chemical plating or electroplating) is a widely used and flexible material surface treatment process, and copper-plated welding wire is one such method.

[0006] Traditional welding wire manufacturing employs a smelting-drawing method, where the alloy composition is added and measured during the smelting process. This method is time-consuming and costly. Traditional copper plating of welding wire involves coating the surface with a layer of copper metal of a certain thickness (usually 0.2-0.5μm) to prevent rust and improve welding processability (increasing conductivity and reducing friction). Commercially available welding wires are limited; widely used, high-volume products are readily available, while niche products with lower usage are difficult to find. New, specially designed steel welding wires with special alloy contents often require small laboratory furnaces for alloying, resulting in lower precision and significant differences from industrial mass production. Using large furnaces is costly, unsuitable for small quantities, and uneconomical. Summary of the Invention

[0007] In order to overcome the shortcomings of the prior art, the present invention aims to provide a method for manufacturing alloy steel welding wire by coating, so as to solve the technical problems of traditional welding wire manufacturing using the smelting-drawing method, where the alloy composition is added and measured and controlled during the smelting process, and the manufacturing cycle is long, the cost is high, and welding wires with special requirements cannot be mass-produced.

[0008] To achieve the above objectives, the present invention employs the following technical solution:

[0009] This invention provides a method for manufacturing alloy steel welding wire using a coating method, comprising the following steps:

[0010] S1: A coating is applied to the surface of the welding wire according to a preliminary thickness to obtain a coated welding wire; the preliminary thickness is determined based on the analysis of the welding wire to obtain the original content of elements in the welding wire and the given design value of the welding wire alloy content, and the alloy content in the coating is determined; then the preliminary thickness of the welding wire alloy coating is determined according to the alloy content in the coating.

[0011] S2: Analyze and test to obtain the alloy content of the welding wire after coating, compare the alloy content of the welding wire after coating with the design value of the welding wire alloy content, and obtain the adjustment coefficient of the alloy coating.

[0012] S3: Determine the adjusted thickness of the alloy coating based on the adjustment coefficient of the alloy coating;

[0013] S4: Adjust the thickness of the alloy coating and re-coat the welding wire.

[0014] Furthermore, in step S1, the method for determining the alloy content in the coating is as follows:

[0015] X t =X i -X a

[0016] Among them, X t X represents the alloy content in the coating. i X is the design value for the alloy content of the welding wire. a This represents the original element content in the welding wire.

[0017] Furthermore, in step S1, the method for determining the preliminary thickness of the welding wire alloy coating is as follows:

[0018]

[0019] Among them, X t δ is the alloy content in the coating; δ1 is the initial thickness of the alloy coating on the welding wire; d0 is the diameter of the steel welding wire; ρ0 is the density of the steel; ρ1 is the density of the alloy.

[0020] In a further step of the present invention, in step S1, the coating on the surface of the welding wire according to the preliminary thickness is performed by chemical plating.

[0021] Furthermore, the chemical plating method of the present invention involves passing the welding wire sequentially through an alkaline washing tank, a water washing tank, a surface acidification tank, a chemical plating tank, a hot water cleaning tank, and a cold water washing tank, and finally drying it to obtain a welding wire with a bright surface coating.

[0022] In a further step of this invention, in step S2, the method for comparing the alloy content of the welding wire after coating with the designed value of the welding wire alloy content is as follows:

[0023] k=(X i -X s ) / X s ;

[0024] Where k is the adjustment coefficient; X i X is the design value for the alloy content of the welding wire; s This represents the measured value of the alloy content of the welding wire after coating.

[0025] Furthermore, in step S3, the method for determining the thickness adjustment of the alloy coating is as follows:

[0026] δ = δ1(1+k);

[0027] Where δ is the adjusted thickness of the alloy coating; δ1 is the initial thickness of the alloy coating on the welding wire; and k is the adjustment coefficient.

[0028] Furthermore, in step S3, the method for determining the thickness of the alloy coating further includes:

[0029] If the adjustment factor is 0, no adjustment is needed, and the coating thickness is the final required thickness.

[0030] If the adjustment coefficient is greater than or equal to 0, the coating thickness is too small, and it is adjusted and increased according to δ, i.e., the adjustment thickness of the alloy coating.

[0031] If the adjustment coefficient is less than 0, the coating thickness is too large, and it is adjusted to reduce the thickness according to δ, i.e., the adjustment thickness of the alloy coating.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] This invention provides a method for manufacturing alloy steel welding wire using a coating method. The method adjusts the thickness of the alloy coating through calculation and experimental analysis. By coating one or more layers of a specific alloy layer of a certain thickness onto the surface of existing welding wire, the alloy content in the steel welding wire is increased. This achieves the goal of controlling the alloy content in the welding wire and weld metal, meeting the requirements for weld metallization in welding special structures and materials. Compared with traditional welding wire manufacturing processes such as smelting, forging, and drawing, this method utilizes readily available welding wire from the market and manufactures alloy welding wire with a set content using this invention's technology. By changing the coating thickness, the content of a certain alloy element in the existing welding wire is increased. The coating method of this invention is flexible, and thickness control is easily achieved. Welding wire manufactured using this technology requires less investment, is environmentally friendly, allows for convenient composition adjustment, has low cost, and a short production cycle. It can economically and efficiently solve the problem of special welding material needs in scientific research and production. The alloy coating on the welding wire also has rust-proofing properties. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the cross-section of the two-coated welding wire of the present invention;

[0035] Figure 2 This is a schematic diagram of the cross-section of the three-coated welding wire of the present invention;

[0036] Wherein: 1-steel welding wire; 2-first coating layer; 3-second coating layer; 4-third coating layer. Detailed Implementation

[0037] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.

[0038] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0039] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0040] In this article, unless otherwise specified, “contains,” “includes,” “containing,” “has,” or similar terms cover the meanings of “composed of” and “mainly composed of,” for example, “A contains a” covers the meanings of “A contains a and others” and “A contains only a.”

[0041] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0042] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0043] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.

[0044] This invention provides a method for manufacturing alloy steel welding wire using a coating method, comprising the following steps:

[0045] S1: A coating is applied to the surface of the welding wire according to a preliminary thickness to obtain a coated welding wire; the preliminary thickness is determined based on the analysis of the welding wire to obtain the original content of elements in the welding wire and the given design value of the welding wire alloy content, and the alloy content in the coating is determined; then the preliminary thickness of the welding wire alloy coating is determined according to the alloy content in the coating.

[0046] S2: Analyze and test to obtain the alloy content of the welding wire after coating, compare the alloy content of the welding wire after coating with the design value of the welding wire alloy content, and obtain the adjustment coefficient of the alloy coating.

[0047] S3: Determine the adjusted thickness of the alloy coating based on the adjustment coefficient of the alloy coating;

[0048] S4: Adjust the thickness of the alloy coating and re-coat the welding wire.

[0049] The method for determining the alloy content in the coating is as follows:

[0050] X t =X i -X a

[0051] Among them, X t X represents the alloy content in the coating. i X is the design value for the alloy content of the welding wire. a This represents the original element content in the welding wire.

[0052] The method for determining the preliminary thickness of the welding wire alloy coating is as follows:

[0053]

[0054] Among them, X t δ is the alloy content in the coating; δ1 is the initial thickness of the alloy coating on the welding wire; d0 is the diameter of the steel welding wire; ρ0 is the density of the steel; ρ1 is the density of the alloy.

[0055] The method for comparing the alloy content of the welding wire after coating with the designed value of the welding wire alloy content is as follows:

[0056] k=(X i -X s ) / X s

[0057] Where k is the adjustment coefficient; X i X is the design value for the alloy content of the welding wire; s This represents the measured value of the alloy content of the welding wire after coating.

[0058] The method for determining the adjusted thickness of the alloy coating is as follows:

[0059] δ=δ1(1-k);

[0060] Where δ is the adjusted thickness of the alloy coating; δ1 is the initial thickness of the alloy coating on the welding wire; and k is the adjustment coefficient.

[0061] The method for determining the thickness of the alloy coating further includes:

[0062] If K=0, no adjustment is needed, and the coating thickness is the final required thickness;

[0063] If K > 0, the coating thickness is too small and needs to be increased. The increase is made according to δ, which is the adjustment thickness of the alloy coating.

[0064] If K < 0, the coating thickness is too large and needs to be reduced. The reduction is made according to δ, which is the adjustment thickness of the alloy coating.

[0065] A certain alloy coating is applied to the surface of the welding wire using a chemical plating method, the chemical plating comprising the following steps:

[0066] The welding wire is passed through an alkaline washing tank, a water washing tank, a surface acidification tank, a chemical plating tank, a hot water cleaning tank, and a cold water washing tank in sequence, and finally dried to obtain a welding wire with a bright surface coating.

[0067] The thickness of the coating is controlled by adjusting the concentration, temperature and time of the plating solution.

[0068] Example

[0069] The CHW-50C2 welding wire produced by Atlantic Welding Materials Co., Ltd. has a diameter of 1.0 mm and conforms to GB / T8110 ER50S-2. Copper plating is not required. Its chemical composition standard requirements and typical values ​​are shown in Table 1.

[0070] When using CO2 gas shielded welding, the standard guaranteed value of impact toughness of the weld metal at -30℃ is ≥27J, which does not meet the requirement of ≥54J required by a certain project.

[0071] Nickel (Ni) is an alloying element that can significantly improve the low-temperature toughness of welds and also has rust-preventive properties. This welding wire actually contains very little Ni (generally <0.15%). Therefore, a welding wire with a Ni content of 1.0% is designed to meet the requirement that the weld formed by the welding wire has a low-temperature impact toughness of ≥54J at -30℃.

[0072] Table 1 Chemical composition of welding wire (wt.%)

[0073] C Mn Si S P Ti Cu Al Zr other Standard value ≤0.07 0.90-1.40 0.40-0.70 ≤0.025 ≤0.025 0.05-0.15 ≤0.50 0.05-0.15 0.02-0.12 - Typical value 0.05 1.20 0.60 0.010 0.016 0.11 0.20 0.080 0.080 ≤0.50

[0074] The method of increasing the Ni content in welding wire to 1.0% using a single-layer plating method, while keeping other components unchanged, is as follows:

[0075] S1: Welding wire selection. Easily procurable non-copper-plated welding wire is selected as the basic raw material for the coated welding wire. Its basic chemical composition (C, Si, Mn, S, P) and the content of non-coated alloying elements meet the requirements. The original content of elements in the welding wire is obtained and the design value of the welding wire alloy content is given to determine the alloy content in the coating.

[0076] S2: Determine the initial thickness of the coating by calculation using the formula;

[0077] S3: Plate an alloy layer of initially determined thickness onto the surface of the basic raw material welding wire;

[0078] S4: Conduct tests to determine whether the alloy content in the welding wire meets the expected requirements, and make adjustments if necessary;

[0079] S5: Determine the final thickness of the coating.

[0080] Other coating methods can also be used to apply a certain alloy coating to the surface of the welding wire.

[0081] Step 1: Calculate the Ni coating content in the welding wire.

[0082] Analysis of the actual Ni content X of the purchased CHW-50C2 welding wire a =0.09, calculate the Ni content of the welding wire coating using formula 1).

[0083] X t =X i -X a =1.0-0.09=0.91 1)

[0084] In the formula: X t —Alloy content in the coating, %.

[0085] X i —Designed content of a certain element in the welding wire or the designed value of the welding wire alloy content, %.

[0086] X a —The original content of a certain element in the welding wire, %.

[0087] Step 2: Calculate the preliminary thickness of the welding wire coating.

[0088] Given the diameter d0 of the steel welding wire, the density ρ0 of the steel, the density ρ1 of the nickel, and the Ni content X of the coating in the welding wire. t By solving equation 2), the initial thickness of the Ni coating δ1 = 0.002 mm (2 μm) was calculated.

[0089]

[0090] Table 2 Calculation parameters and results for the thickness of the welding wire coating

[0091]

[0092] In the formula: X t The alloy content in the coating; %.

[0093] δ1 is the initial thickness of the alloy coating on the welding wire; mm.

[0094] d0 is the diameter of the steel welding wire; mm.

[0095] ρ0 is the density of steel; g / cm³ 3 .

[0096] ρ1 is the density of the alloy; g / cm³ 3 .

[0097] Step 3: Apply Ni coating to the original welding wire.

[0098] Ni is plated onto the surface of the original welding wire using a chemical plating method with low-phosphorus or phosphorus-free plating solution, and the initial thickness of the Ni plating layer is controlled to be 2 μm, which is the thickness calculated in step 2.

[0099] The chemical plating method involves passing the welding wire sequentially through an alkaline washing tank, a water washing tank, a surface acidification tank, a chemical plating tank, a hot water cleaning tank, and a cold water washing tank, and finally drying it to obtain a welding wire with a bright surface coating.

[0100] Step 4: Ni content testing and comparison of the coated welding wire

[0101] According to the test method specified in the standard, the Ni content X in the welding wire after coating was tested. s Testing was conducted to determine the Ni content X in the welding wire design. i Compare the values ​​and calculate the adjustment factor according to formula 3). For example, X i =1.0, X s =0.85, k1=0.176; X i =1.0, X s =1.10, k2=-0.091.

[0102] k=(X i -X s ) / X s 3)

[0103] Where: k—adjustment coefficient;

[0104] X i —Design value for Ni content in welding wire;

[0105] X s —Measured value of Ni content in the welding wire after coating.

[0106] Step 5: Adjusting the Ni coating thickness

[0107] Analyze the adjustment coefficient in step 4. If k = 0, no adjustment is needed. The coating thickness δ1 = 2 μm determined in step 2 is the final required thickness δ.

[0108] If k > 0, it indicates that the coating thickness determined in step 2 is too small and needs to be increased. The final required thickness is calculated and adjusted according to formula 4). For example, if k = 0.176 and δ1 = 2μm in step 4, then the final required coating thickness δ = 2.4μm.

[0109] If k < 0, it indicates that the coating thickness determined in step 2 is too large and needs to be reduced. The final required thickness is calculated and adjusted according to formula 4). For example, if k = -0.091 and δ1 = 2μm in step 4, then the final required coating thickness δ = 1.82μm.

[0110] δ=δ1(1+k) 4)

[0111] Where: δ—adjusted thickness of the alloy coating;

[0112] δ1—Initial thickness of the alloy coating;

[0113] k — Adjustment coefficient.

[0114] Step 6: Re-plating and welding test

[0115] Following step 5, the welding wire was re-coated with adjusted thickness. The Ni content in the welding wire was tested and found to be 0.98%, meeting the expected requirements. Welding tests were conducted using this coated welding wire, and the low-temperature impact toughness of the weld at -30℃ was tested to be 107J, meeting the technical requirement of ≥54J with a large margin.

[0116] This invention provides a method for manufacturing alloy steel welding wire using a coating method. The method plays a crucial role in ensuring the weld performance of the welding wire by controlling the content of added alloying elements. Commercially available, mass-produced welding wires with basic chemical compositions (C, Si, Mn, S, P, and other elements) meeting requirements are used. One or more special alloy layers of a specific thickness are added to the surface of the wire using a coating method, thereby increasing the alloy content in the steel welding wire. This achieves alloying of the solid welding wire and the weld metal, thus improving the weld performance of the welded parts and meeting the service requirements of special materials and structures (e.g., the requirement that the weld formed by the welding wire has a low-temperature impact toughness ≥54J at -30℃). Compared to traditional manufacturing methods, this invention utilizes readily available welding wire to manufacture alloy welding wires with a set content. Since the thickness of the coating depends on the time of the coating process and the concentration and temperature of the coating solution, changing the coating thickness can adjust the content of a specific alloy element in the welding wire. Therefore, adjusting the alloy composition of the welding wire only requires adjusting the time of the coating process or the concentration and temperature of the solution, thereby changing the coating thickness to meet the requirements of more special material properties, reducing production costs and saving time.

[0117] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for manufacturing alloy steel welding wire using a coating method, characterized in that, Includes the following steps: S1: A coating is applied to the surface of the welding wire according to a preliminary thickness to obtain a coated welding wire; the preliminary thickness is based on the original element content X obtained from the analysis of the welding wire. a And give the design value X of welding wire alloy content. i Determine the alloy content X in the coating. t Then, based on the alloy content X in the coating... t Determine the initial thickness δ1 of the alloy coating on the welding wire; In step S1, the method for determining the alloy content in the coating is as follows: Among them, X t X represents the alloy content in the coating. i X is the design value for the alloy content of the welding wire. a This represents the original elemental content in the welding wire; The method for determining the preliminary thickness of the welding wire alloy coating is as follows: Among them, X t δ is the alloy content in the coating; δ1 is the initial thickness of the alloy coating on the welding wire; d0 is the diameter of the steel welding wire; ρ0 is the density of the steel; ρ1 is the density of the alloy. S2: Analytical testing to obtain the alloy content X of the welding wire after coating. s The alloy content X of the welding wire after coating s Design value X of welding wire alloy content i By comparison, the adjustment coefficient k of the alloy coating is obtained; In step S2, the method for comparing the alloy content of the welding wire after coating with the designed value of the welding wire alloy content is as follows: ； Where k is the adjustment coefficient; X i X is the design value for the alloy content of the welding wire; s This is the measured value of the alloy content of the welding wire after coating; S3: Based on the adjustment coefficient k of the alloy coating, according to the formula Where δ is the adjusted thickness of the alloy coating, the adjusted thickness of the alloy coating δ is determined; S4: the welding wire is coated again according to the adjusted thickness of the alloy coating δ.

2. The method according to claim 1, characterized in that, In step S1, the coating on the surface of the welding wire according to the initial thickness is achieved by chemical plating.

3. The method according to claim 2, characterized in that, The chemical plating method involves passing the welding wire sequentially through an alkaline washing tank, a water washing tank, a surface acidification tank, a chemical plating tank, a hot water cleaning tank, and a cold water washing tank, and finally drying it to obtain a welding wire with a bright surface coating.

4. The method according to claim 1, characterized in that, In step S3, the method for determining the thickness of the alloy coating further includes: If the adjustment factor is 0, no adjustment is needed, and the coating thickness is the final required thickness. If the adjustment coefficient is greater than or equal to 0, the coating thickness is too small, and it is adjusted and increased according to δ, i.e., the adjustment thickness of the alloy coating. If the adjustment coefficient is less than 0, the coating thickness is too large, and it is adjusted to reduce the thickness according to δ, i.e., the adjustment thickness of the alloy coating.

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