TIG welding wire surface treatment method based on straightening pressure

Abstract

The invention belongs to the technical field of welding wire treatment, and discloses a TIG (Tungsten Inert Gas) welding wire surface treatment method based on straightening pressure, which comprises the following steps: pretreating a round steel wire rod with a preset diameter to form a phosphate film on the surface of the round steel wire rod, and coating a dry film lubricant on the surface of the phosphate film to form a continuous lubricating layer; the round steel wire rod is sequentially subjected to multi-pass drawing treatment by utilizing the drawing die and selecting lubricating oil of a preset type, the hole diameter of the drawing die is gradually reduced in each pass of drawing treatment, and the drawn welding wire is obtained; and the drawn welding wire is fed into roller type straightening equipment, gradient pressure is applied through a plurality of straightening rollers arranged in a staggered mode of the roller type straightening equipment to conduct straightening treatment on the welding wire, and the straightened welding wire is obtained. Through multi-pass treatment of rough drawing and fine drawing, intermediate annealing, cleaning, phosphorization and lubricant supplementary coating are combined, the hardening phenomenon is effectively avoided, and the flexibility and ductility of the welding wire are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of welding wire processing, and in particular to a TIG welding wire surface processing method based on straightening pressure. Background Art

[0002] TIG welding wire is a consumable material used in tungsten inert gas (TIG) welding. Made from metals such as stainless steel or aluminum alloy, it exhibits excellent electrical conductivity and high-temperature resistance. TIG welding is a filler-free welding method in which the wire acts as a filler material, melting and forming the weld with the workpiece.

[0003] During the TIG welding wire production process, the drawing stage primarily focuses on size reduction and metal flow deformation. Consequently, the wire surface is inevitably subject to significant friction and mechanical stress, making effective surface treatment of the wire extremely difficult. Particularly during the drawing process, residual lubricant, the formation of metal microcracks, and the accumulation of surface stress can limit the effectiveness of surface treatment and severely impact the wire's surface quality. For example, failure to completely remove lubricant can lead to surface contamination, and metal microcracks can expand during subsequent processing, compromising the wire's mechanical properties and service life, ultimately impacting subsequent processing.

[0004] Therefore, how to provide a TIG welding wire surface treatment method based on straightening pressure is a problem that needs to be solved urgently. Summary of the Invention

[0005] An embodiment of the present invention provides a TIG welding wire surface treatment method based on straightening pressure to solve the problems in the prior art of lubricant residue, metal microcrack formation and surface stress accumulation, which lead to limited surface treatment effects.

[0006] To provide a basic understanding of some aspects of the disclosed embodiments, the following is a brief summary. This summary is not intended to be an extensive review, identify key or critical elements, or delineate the scope of these embodiments. Its sole purpose is to present some concepts in a simplified form as a prelude to the detailed description that follows.

[0007] According to an embodiment of the present invention, a TIG welding wire surface treatment method based on straightening pressure is provided.

[0008] In one embodiment, the TIG welding wire surface treatment method based on straightening pressure includes: Pre-treating a round steel wire rod of a preset diameter to form a phosphate film on the surface of the round steel wire rod, and coating the surface of the phosphate film with a dry film lubricant to form a continuous lubricating layer; The round steel wire rod is sequentially drawn in multiple passes using a drawing die and a preset type of lubricating oil, and the aperture of the drawing die is gradually reduced in each drawing pass to obtain a drawn welding wire; The drawn welding wire is fed into a roller-type straightening device, and a plurality of staggered straightening rollers of the roller-type straightening device apply gradient pressure to the welding wire to straighten it, thereby obtaining a straightened welding wire; The straightened welding wire is degreased, and the quality of the welding wire surface is evaluated after the degreasing treatment is completed.

[0009] In one embodiment, pre-treating a round steel wire rod of a preset diameter to form a phosphate film on the surface of the round steel wire rod, and coating the phosphate film surface with a dry film lubricant to form a continuous lubricating layer comprises: adding a corrosion inhibitor to hydrochloric acid to obtain a first mixed solution, pickling the round steel wire rod with the first mixed solution, and then ultrasonically cleaning the round steel wire rod with cold water and deionized water in sequence after the pickling is completed; adding a nitrate accelerator to the phosphate to obtain a second mixed solution, and applying the second mixed solution to the surface of the cleaned round steel wire rod to form a phosphate film; Nano-molybdenum disulfide is added to the calcium-based lubricant to obtain a third mixed solution, and the third mixed solution is sprayed onto the phosphate film by electrostatic spraying to form a continuous lubricating layer on the surface of the phosphate film.

[0010] In one embodiment, the method of sequentially drawing the round steel wire rod using a drawing die and a preset type of lubricating oil, and gradually reducing the diameter of the drawing die aperture in each drawing process to obtain the drawn welding wire includes: The round steel wire rod is roughly drawn using a drawing die with a preset taper angle, and the compression rate of each drawing die is 15-20%; After several rough drawing, the surface of the welding wire is checked for hardening. If hardening is found, the welding wire is subjected to intermediate annealing. After annealing, secondary cleaning, phosphating and lubricant re-coating are carried out in sequence. Otherwise, the wire enters the finishing drawing stage. The round steel wire rod is finely drawn using a drawing die with a preset taper angle, and the compression rate of each pass of the drawing die is 10-12%; After fine drawing, ultrasonic assisted electrolytic polishing technology is used to remove micro cracks on the surface of the drawn welding wire.

[0011] In one embodiment, the preset taper angle of the drawing die in the rough drawing stage is 10°~12°, and the lubricating oil is high-viscosity mineral oil; the preset taper angle of the drawing die in the fine drawing stage is 6°~8°, and the lubricating oil is nanographite lubricant.

[0012] In one embodiment, the method of removing surface microcracks of the drawn welding wire by using ultrasonic assisted electrolytic polishing technology after fine drawing comprises: Immerse the fine-drawn welding wire in alkaline degreasing solution for 5 to 10 minutes to remove residual lubricant on the surface; A preset amount of phosphoric acid, sulfuric acid, glycerin, and deionized water are mixed and stirred to prepare an electrolyte. The welding wire is then passed through the electrolytic cell at a constant speed. The ultrasonic equipment and electrolytic power supply are activated to simultaneously perform electrochemical dissolution and mechanical cavitation to remove microcracks on the surface of the drawn welding wire. The welding wire with surface microcracks removed is taken out of the electrolytic cell and the residual electrolyte is removed using deionized water.

[0013] In one embodiment, the mass ratio of phosphoric acid, sulfuric acid, glycerol and deionized water in the electrolyte is 8:4:1:7.

[0014] In one embodiment, the drawn welding wire is fed into a roller-type straightening device, and a plurality of staggered straightening rollers of the roller-type straightening device are used to apply gradient pressure to the welding wire to straighten the welding wire, thereby obtaining the straightened welding wire. The drawn welding wire is fed into the roller straightening device through the guide wheel group, and the deviation between the welding wire axis and the center line of the straightening roller is calibrated using a laser alignment sensor; The roller-type straightening equipment uses several staggered straightening rollers to apply different gradient pressures step by step, and the pressure applied by each straightening roller decreases in sequence to correct the welding wire to a straight shape; A residual stress detector pre-installed between the straightening rollers is used to monitor the axial stress changes of the welding wire during the straightening process in real time. The axial stress changes are compared with a preset threshold. If the axial stress change is greater than the preset threshold, the wire springback compensation algorithm is triggered to adjust the straightening roller spacing. Wherein, the straightening roller group includes a coarse straightening roller group and a fine straightening roller group.

[0015] In one embodiment, applying different gradient pressures step by step through a plurality of staggered straightening roller groups in a roller-type straightening device includes: The coarse straightening rollers in the roller-type straightening equipment are used to apply high pressure to eliminate the large curvature of the welding wire, and the pressure direction of the coarse straightening rollers is vertically staggered; The fine-adjusting straightening roller group in the roller-type straightening equipment is switched to low pressure, and the pressure direction of the fine-adjusting straightening roller group applying low pressure is horizontally staggered.

[0016] In one embodiment, comparing the axial stress change with a preset threshold, and triggering a wire springback compensation algorithm to adjust the straightening roller spacing if the axial stress change is greater than the preset threshold, includes: Compare the axial stress change with a preset threshold value, and if the axial stress change is greater than the preset threshold value, reduce the hydraulic pressure of the straightening roller group proportionally; The hydraulic pressure of the straightening roller group after reduction and the elastic modulus of the welding wire are input into the predefined welding wire springback compensation model to calculate the welding wire springback compensation amount, and the spacing of the straightening roller group is compensated according to the welding wire springback compensation amount; After the straightening roller group spacing is compensated, the axial stress change is re-detected and compared with the preset threshold value for a second time. If it is less than or equal to the preset threshold value, it indicates that the compensation is successful. Otherwise, the compensation amount is increased by 10% through secondary compensation, and the pressure of the straightening roller group is extended for 3 seconds.

[0017] In one embodiment, proportionally reducing the hydraulic pressure of the straightening roller set includes: Reduce the pressure of the coarse straightening roller group from 15MPa to 12MPa, and reduce the pressure of the fine straightening roller group from 8MPa to 6.4MPa.

[0018] The technical solution provided by the embodiment of the present invention may have the following beneficial effects: 1. The present invention adopts hydrochloric acid with added corrosion inhibitor for pickling, which can effectively remove the oxide scale, rust and attached impurities on the surface of the wire rod. At the same time, the introduction of the corrosion inhibitor reduces the corrosion damage of the substrate during the pickling process, ensuring the integrity of the wire rod matrix. The second mixed solution prepared by adding a nitrate accelerator to the phosphate can accelerate the formation process of the phosphate film, so that the phosphate film is quickly deposited on the surface of the steel to form a fine and uniform crystalline structure. At the same time, the calcium-based lubricant with added nano-molybdenum disulfide is evenly coated on the surface of the phosphate film by electrostatic spraying to form a dense dry film lubrication layer, thereby significantly reducing the friction coefficient in the subsequent drawing process and slowing down the wear of the mold.

[0019] 2. The present invention effectively avoids hardening through multiple processes of rough drawing and fine drawing, combined with intermediate annealing, cleaning, phosphating and lubricant re-coating, ensuring the flexibility and ductility of the welding wire. Nano-graphite lubricant and small cone-angle mold are used in the fine drawing stage to reduce friction, improve efficiency, and ensure a smooth surface. Ultrasonic-assisted electrolytic polishing is combined to remove microcracks, improve the surface flatness and corrosion resistance of the welding wire, and ensure its high quality, long life and excellent welding performance.

[0020] 3. The present invention realizes gradient straightening of the welding wire after drawing by setting coarse straightening and fine straightening roller groups, effectively eliminating large curvature bending and ensuring the straightness of the welding wire, and adopts vertical and horizontal staggered roller group arrangement to improve straightening accuracy. At the same time, combined with laser centering and stress monitoring system, the straightening pressure and roller spacing are regulated in real time, and the parameters are dynamically adjusted through the welding wire springback compensation model to ensure that the axial stress is controlled within the preset range, effectively preventing springback deformation, and thus improving the straightening accuracy and the quality of the finished welding wire.

[0021] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0023] Figure 1 The figure is a flow chart showing a TIG welding wire surface treatment method based on straightening pressure according to an exemplary embodiment. DETAILED DESCRIPTION

[0024] The following description and accompanying drawings sufficiently illustrate the specific embodiments herein to enable those skilled in the art to practice them. Portions and features of some embodiments may be included in or substituted for portions and features of other embodiments. The scope of the embodiments herein includes the entire scope of the claims, including all available equivalents thereof. Herein, the terms "first," "second," and the like are used solely to distinguish one element from another and do not require or imply any actual relationship or order between these elements. In practice, the first element can also be referred to as the second element, and vice versa. Furthermore, the terms "comprise," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a structure, device, or apparatus comprising a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such structure, device, or apparatus. Without further limitation, an element defined by the phrase "comprising a..." does not preclude the presence of other identical elements in the structure, device, or apparatus comprising the element. The various embodiments herein are described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. Similar or identical parts between the various embodiments can be referenced to each other.

[0025] The terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like used herein to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are intended only to facilitate the description of this document and simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present invention. In the description herein, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, they can be mechanical or electrical connections, or they can be internal connections between two elements, they can be directly connected, or they can be indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0026] As used herein, unless otherwise specified, the term "plurality" means two or more.

[0027] In this document, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B means: A or B.

[0028] In this article, the term "and / or" is used to describe the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0029] It should be understood that, although the various steps in the flowchart are shown in sequence as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps may be performed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but may be performed at different times. The execution order of these sub-steps or stages is not necessarily to be performed in sequence, but may be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0030] In the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0031] Figure 1 An embodiment of the TIG welding wire surface treatment method based on straightening pressure of the present invention is shown.

[0032] In this optional embodiment, the TIG welding wire surface treatment method based on straightening pressure includes: S101, pre-treating a round steel wire rod of a preset diameter to form a phosphate film on the surface of the round steel wire rod, and coating the surface of the phosphate film with a dry film lubricant to form a continuous lubricating layer; S102, using a drawing die and a preset type of lubricating oil to sequentially draw the round steel wire rod in multiple passes, and gradually reducing the diameter of the drawing die in each drawing pass to obtain a drawn welding wire; S103, feeding the drawn welding wire into a roller-type straightening device, and applying gradient pressure to the welding wire by a plurality of staggered straightening rollers of the roller-type straightening device to straighten the welding wire, thereby obtaining a straightened welding wire; S104, degreasing the straightened welding wire, and evaluating the quality of the welding wire surface after the degreasing is completed.

[0033] In this optional embodiment, pre-treating the round steel wire rod of a preset diameter to form a phosphate film on the surface of the round steel wire rod, and coating the phosphate film surface with a dry film lubricant to form a continuous lubricating layer includes: adding a corrosion inhibitor to hydrochloric acid to obtain a first mixed solution, pickling the round steel wire rod with the first mixed solution, and then ultrasonically cleaning the round steel wire rod with cold water and deionized water in sequence after the pickling is completed; adding a nitrate accelerator to the phosphate to obtain a second mixed solution, and applying the second mixed solution to the surface of the cleaned round steel wire rod to form a phosphate film; Nano-molybdenum disulfide is added to the calcium-based lubricant to obtain a third mixed solution, and the third mixed solution is sprayed onto the phosphate film by electrostatic spraying to form a continuous lubricating layer on the surface of the phosphate film.

[0034] In this optional embodiment, the method of sequentially drawing the round steel wire rod using a drawing die and selecting a preset type of lubricating oil, and gradually reducing the diameter of the drawing die aperture in each drawing process to obtain the drawn welding wire includes: The round steel wire rod is roughly drawn using a drawing die with a preset taper angle, and the compression rate of each drawing die is 15-20%; After several rough drawing, the surface of the welding wire is checked for hardening. If hardening is found, the welding wire is subjected to intermediate annealing. After annealing, secondary cleaning, phosphating and lubricant re-coating are carried out in sequence. Otherwise, the wire enters the finishing drawing stage. The round steel wire rod is finely drawn using a drawing die with a preset taper angle, and the compression rate of each pass of the drawing die is 10-12%; After fine drawing, ultrasonic assisted electrolytic polishing technology is used to remove micro cracks on the surface of the drawn welding wire.

[0035] In this optional embodiment, the preset taper angle of the drawing die in the rough drawing stage is 10° to 12°, and the lubricating oil is high-viscosity mineral oil; The preset taper angle of the drawing die in the fine drawing stage is 6°~8°, and the lubricating oil is nanographite lubricant.

[0036] It should be noted that in the rough drawing stage, the preset larger cone angle (10°~12°) makes the welding wire more evenly stressed during the drawing process, which helps to eliminate large bending deformation. At the same time, high-viscosity mineral oil as a lubricant can effectively reduce friction, reduce drawing force, prevent scratches or damage on the welding wire surface, and maintain good surface quality; entering the fine drawing stage, the smaller cone angle (6°~8°) makes the drawing process more refined, which can further improve the dimensional accuracy of the welding wire. At the same time, the addition of nano-graphite lubricant enhances the lubrication effect, reduces the friction coefficient, reduces the surface temperature, improves the drawing efficiency, and effectively improves the surface finish of the welding wire, preventing micro-cracks on the surface and ensuring high-quality welding wire products.

[0037] In this optional embodiment, the use of ultrasonic assisted electrolytic polishing technology to remove surface microcracks of the drawn welding wire after fine drawing includes: Immerse the fine-drawn welding wire in alkaline degreasing solution for 5 to 10 minutes to remove residual lubricant on the surface; A preset amount of phosphoric acid, sulfuric acid, glycerin, and deionized water are mixed and stirred to prepare an electrolyte. The welding wire is then passed through the electrolytic cell at a constant speed. The ultrasonic equipment and electrolytic power supply are activated to simultaneously perform electrochemical dissolution and mechanical cavitation to remove microcracks on the surface of the drawn welding wire. The welding wire with surface microcracks removed is taken out of the electrolytic cell and the residual electrolyte is removed using deionized water.

[0038] In this optional embodiment, the mass ratio of phosphoric acid, sulfuric acid, glycerol and deionized water in the electrolyte is 8:4:1:7.

[0039] It should be noted that the electrolyte should be prepared according to the mass ratio of phosphoric acid, sulfuric acid, glycerol and deionized water of 8:4:1:7. That is, when preparing every 20g of total mass of electrolyte, weigh 8g of phosphoric acid, 4g of sulfuric acid, 1g of glycerol and 7g of deionized water, and add them to the stirring container in sequence. First add phosphoric acid and sulfuric acid and mix them evenly, then add glycerol and continue stirring, and finally slowly add deionized water to dilute to the target concentration. Stir continuously throughout the process to ensure that all components are fully dissolved to form a uniform and stable electrolyte.

[0040] In this optional embodiment, the drawn welding wire is fed into a roller-type straightening device, and a plurality of staggered straightening rollers of the roller-type straightening device are used to apply gradient pressure to the welding wire to straighten the welding wire, thereby obtaining the straightened welding wire. The drawn welding wire is fed into the roller straightening device through the guide wheel group, and the deviation between the welding wire axis and the center line of the straightening roller is calibrated using a laser alignment sensor; The roller-type straightening equipment uses several staggered straightening rollers to apply different gradient pressures step by step, and the pressure applied by each straightening roller decreases in sequence to correct the welding wire to a straight shape; A residual stress detector pre-installed between the straightening rollers is used to monitor the axial stress changes of the welding wire during the straightening process in real time. The axial stress changes are compared with a preset threshold. If the axial stress change is greater than the preset threshold, the wire springback compensation algorithm is triggered to adjust the straightening roller spacing. Wherein, the straightening roller group includes a coarse straightening roller group and a fine straightening roller group.

[0041] In this optional embodiment, applying different gradient pressures step by step through a plurality of staggered straightening roller groups in the roller-type straightening device includes: The coarse straightening roller group in the roller straightening equipment is used to apply high pressure to eliminate the large curvature of the welding wire, and the pressure direction of the coarse straightening roller group applying high pressure is vertically staggered.

[0042] The fine-adjusting straightening roller group in the roller-type straightening equipment is switched to low pressure, and the pressure direction of the fine-adjusting straightening roller group applying low pressure is horizontally staggered.

[0043] In this optional embodiment, comparing the axial stress change with a preset threshold value, and triggering the wire springback compensation algorithm to adjust the straightening roller spacing if the axial stress change is greater than the preset threshold value, includes: Compare the axial stress change with a preset threshold value, and if the axial stress change is greater than the preset threshold value, reduce the hydraulic pressure of the straightening roller group proportionally; The hydraulic pressure of the straightening roller group after reduction and the elastic modulus of the welding wire are input into the predefined welding wire springback compensation model to calculate the welding wire springback compensation amount, and the spacing of the straightening roller group is compensated according to the welding wire springback compensation amount.

[0044] It should be noted that the hydraulic pressure of the straightening roller group after reduction and the elastic modulus of the welding wire are input into the predefined welding wire springback compensation model to calculate the welding wire springback compensation amount, and the straightening roller group spacing is compensated according to the welding wire springback compensation amount, including: The hydraulic pressure of the straightening roller group after the current reduction and the elastic modulus data of the corresponding welding wire are collected, and these two parameters are imported into the predefined welding wire springback compensation model as input variables; the model calculates the theoretical springback compensation amount of the welding wire under the current straightening force based on the welding wire material properties, stress-strain relationship and springback behavior during the straightening process; the control system accurately adjusts the spacing of the straightening roller group according to the calculated springback compensation amount, and fine-tunes the position of the roller group through the electric actuator or servo drive system to match the actual straightening pressure with the compensation requirement; after the adjustment is completed, the axial stress state of the welding wire is continuously monitored to verify the compensation effect. If the stress recovers to the threshold range, the current setting is maintained. If it is still abnormal, secondary compensation is performed until the welding wire reaches a stable straight line state.

[0045] After the straightening roller group spacing is compensated, the axial stress change is re-detected and compared with the preset threshold value for a second time. If it is less than or equal to the preset threshold value, it indicates that the compensation is successful. Otherwise, the compensation amount is increased by 10% through secondary compensation, and the pressure of the straightening roller group is extended for 3 seconds.

[0046] In this optional embodiment, proportionally reducing the hydraulic pressure of the straightening roller group includes: Reduce the pressure of the coarse straightening roller group from 15MPa to 12MPa, and reduce the pressure of the fine straightening roller group from 8MPa to 6.4MPa.

[0047] It should be noted that the straightened welding wire is degreased and the quality assessment of the welding wire surface is carried out after the degreasing treatment is completed, including: The straightened welding wire is passed through the degreasing tank in sequence. The degreasing liquid can be an alkaline degreasing agent and the processing temperature is controlled within the range of 50~70℃. The immersion time is controlled within 5~10 minutes to fully dissolve and remove the lubricant, oil stains and particulate impurities remaining on the surface of the welding wire; after degreasing, the welding wire is rinsed with clean water or deionized water in multiple stages to ensure that the degreasing agent is completely removed; then the surface of the welding wire is dried using a drying device to prevent water residue from causing oxidation; finally, the quality of the welding wire surface is evaluated by an automatic optical inspection system or manual combined visual inspection.

[0048] Example 1 High-strength stainless steel alloy is selected as the welding wire raw material. The surface treatment of the welding wire includes the following steps: Step 1: Pre-treat a round steel wire rod of a preset diameter by preparing a phosphate solution and coating it to form a phosphate film on the surface of the round steel wire rod. Subsequently, apply a dry film lubricant to form a continuous lubricating layer, providing good lubrication conditions for the drawing process. Step 2: Using the selected drawing die and high-viscosity mineral oil lubricant, the round steel wire rod is drawn in multiple passes. The diameter of the drawing die is gradually reduced in each pass, and finally a welding wire that meets the preset size requirements is obtained; Step 3: The drawn welding wire is fed into a roller-type straightening device. The straightening device applies gradient pressure step by step through multiple staggered straightening rollers to gradually adjust the welding wire to a straight shape, thereby obtaining a straightened welding wire. Step 4: Degrease the straightened wire by soaking it in alkaline degreasing solution at 70°C for 5 minutes to remove residual lubricant on the surface. Then rinse it with deionized water. Finally, evaluate the surface quality of the wire through visual inspection and optical detection equipment to ensure that the surface is free of defects and meets the standard requirements.

[0049] Example 2 High-strength alloy steel is selected as the welding wire raw material, and the surface treatment of the welding wire includes the following steps: Step 1: Pre-treat the round steel wire rod by pickling it with a pickling solution containing a corrosion inhibitor to remove surface oxide scale and impurities. After cleaning, form a phosphate film with a phosphate solution, and apply a dry film lubricant to form a continuous lubricating layer. Step 2: Use high-viscosity mineral oil to lubricate the drawing machine and nano-coated die, perform multiple drawing passes, and gradually reduce the drawing die aperture to make the welding wire reach the preset size requirements and ensure a smooth surface; Step 3: The drawn welding wire is fed into the roller straightening equipment. Through a number of staggered straightening rollers, gradient pressure is applied to gradually straighten the welding wire to a straight shape, and the straightened welding wire is further straightened. Step 4: After straightening, send the welding wire into the degreasing tank for surface degreasing treatment. Soak it in alkaline degreasing solution for 3 minutes, rinse it with deionized water after cleaning, and finally evaluate the quality of the welding wire surface through surface quality inspection equipment.

[0050] Example 3 Low carbon steel alloy is selected as the welding wire raw material, and the surface treatment of the welding wire includes the following steps: Step 1: Pre-treat the round steel wire rod by using heated phosphate solution to form a phosphate film on the surface of the round steel, and then apply dry film lubricant to ensure that the welding wire is well lubricated during the subsequent drawing process; Step 2: Select a suitable drawing die and use nanographite lubricant to draw the round steel wire rod in multiple passes, gradually reducing the die aperture in each pass to obtain a welding wire of precise size; Step 3: The drawn welding wire is straightened by a roller straightening device. A plurality of staggered straightening rollers are used to apply gradient pressure to achieve the best straightness of the welding wire. Step 4: After straightening, the wire is placed in a degreasing tank and cleaned with deionized water to remove any residual lubricant on the surface. The wire surface is then evaluated for quality using high-precision testing equipment.

[0051] Comparative Example 1: The difference from Examples 1-3 is that only a single type of high-viscosity mineral oil is used as a lubricant in the multi-pass drawing process, the lubrication method is not adjusted according to the different drawing stages, and the mold aperture of each pass is not finely controlled, resulting in increased local friction on the surface of the welding wire; no straightening treatment is performed after the drawing is completed, and the welding wire retains a certain degree of residual bending. The residual lubricant on the surface of the welding wire is simply rinsed with normal temperature water, and no effective degreasing treatment is performed. Finally, the welding wire has problems such as oil spots, insufficient smoothness and slight bending in the surface quality inspection, which affects its subsequent welding performance and consistency.

[0052] Table 1 Performance comparison table

[0053] As shown in Table 1, in Comparative Example 1, the lubrication method was not adjusted according to the different drawing stages, and the die aperture of each pass was not finely controlled, resulting in increased local friction on the surface of the welding wire and increased surface roughness, reaching 0.48 μm. Without straightening treatment, the welding wire maintained a large residual bend, the surface quality was poor, and the microcrack density was as high as 8 to 10 per mm. 2 In comparison, the optimization of lubrication, drawing precision control, and post-processing in Examples 1-3 significantly improved the surface quality, and the surface roughness and residual stress were significantly reduced.

[0054] The present invention is not limited to the structures described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A TIG welding wire surface treatment method based on straightening pressure, characterized in that: The method includes: Pre-treating a round steel wire rod of a preset diameter to form a phosphate film on the surface of the round steel wire rod, and coating the surface of the phosphate film with a dry film lubricant to form a continuous lubricating layer; The round steel wire rod is sequentially drawn in multiple passes using a drawing die and a preset type of lubricating oil, and the aperture of the drawing die is gradually reduced in each drawing pass to obtain a drawn welding wire; The drawn welding wire is fed into a roller-type straightening device, and a plurality of staggered straightening rollers of the roller-type straightening device apply gradient pressure to the welding wire to straighten it, thereby obtaining a straightened welding wire; The straightened welding wire is degreased, and the quality of the welding wire surface is evaluated after the degreasing treatment is completed.

2. The TIG welding wire surface treatment method based on straightening pressure according to claim 1, characterized in that: The method of pre-treating a round steel wire rod of a preset diameter to form a phosphate film on the surface of the round steel wire rod, and coating a dry film lubricant on the surface of the phosphate film to form a continuous lubricating layer comprises: adding a corrosion inhibitor to hydrochloric acid to obtain a first mixed solution, pickling the round steel wire rod with the first mixed solution, and then ultrasonically cleaning the round steel wire rod with cold water and deionized water in sequence after the pickling is completed; adding a nitrate accelerator to the phosphate to obtain a second mixed solution, and applying the second mixed solution to the surface of the cleaned round steel wire rod to form a phosphate film; Nano-molybdenum disulfide is added to the calcium-based lubricant to obtain a third mixed solution, and the third mixed solution is sprayed onto the phosphate film by electrostatic spraying to form a continuous lubricating layer on the surface of the phosphate film.

3. The TIG welding wire surface treatment method based on straightening pressure according to claim 1, characterized in that: The method of sequentially drawing the round steel wire rod by using a drawing die and selecting a preset type of lubricating oil, and gradually reducing the diameter of the drawing die aperture in each drawing process to obtain the drawn welding wire includes: The round steel wire rod is roughly drawn using a drawing die with a preset taper angle, and the compression rate of each drawing die is 15-20%; After several rough drawing, the surface of the welding wire is checked for hardening. If hardening is found, the welding wire is subjected to intermediate annealing. After annealing, secondary cleaning, phosphating and lubricant re-coating are carried out in sequence. Otherwise, the wire enters the finishing drawing stage. The round steel wire rod is finely drawn using a drawing die with a preset taper angle, and the compression rate of each pass of the drawing die is 10-12%; After fine drawing, ultrasonic assisted electrolytic polishing technology is used to remove micro cracks on the surface of the drawn welding wire.

4. The TIG welding wire surface treatment method based on straightening pressure according to claim 3, characterized in that: The preset taper angle of the drawing die in the rough drawing stage is 10°~12°, and the lubricating oil is high-viscosity mineral oil; The preset taper angle of the drawing die in the fine drawing stage is 6°~8°, and the lubricating oil is nanographite lubricant.

5. The TIG welding wire surface treatment method based on straightening pressure according to claim 3, characterized in that: The method of removing surface microcracks of the drawn welding wire by using ultrasonic assisted electrolytic polishing technology after fine drawing comprises: Immerse the fine-drawn welding wire in alkaline degreasing solution for 5 to 10 minutes to remove residual lubricant on the surface; A preset amount of phosphoric acid, sulfuric acid, glycerin, and deionized water are mixed and stirred to prepare an electrolyte. The welding wire is then passed through the electrolytic cell at a constant speed. The ultrasonic equipment and electrolytic power supply are activated to simultaneously perform electrochemical dissolution and mechanical cavitation to remove microcracks on the surface of the drawn welding wire. The welding wire with surface microcracks removed is taken out of the electrolytic cell and the residual electrolyte is removed using deionized water.

6. The TIG welding wire surface treatment method based on straightening pressure according to claim 5, characterized in that: The mass ratio of phosphoric acid, sulfuric acid, glycerol and deionized water in the electrolyte is 8:4:1:

7.

7. The TIG welding wire surface treatment method based on straightening pressure according to claim 1, characterized in that: The drawn welding wire is fed into a roller-type straightening device, and a plurality of staggered straightening rollers of the roller-type straightening device are used to apply gradient pressure to the welding wire to straighten the welding wire, thereby obtaining the straightened welding wire. The drawn welding wire is fed into the roller straightening device through the guide wheel group, and the deviation between the welding wire axis and the center line of the straightening roller is calibrated using a laser alignment sensor; The roller-type straightening equipment uses several staggered straightening rollers to apply different gradient pressures step by step, and the pressure applied by each straightening roller decreases in sequence to correct the welding wire to a straight shape; A residual stress detector pre-installed between the straightening rollers is used to monitor the axial stress changes of the welding wire during the straightening process in real time. The axial stress changes are compared with a preset threshold. If the axial stress change is greater than the preset threshold, the wire springback compensation algorithm is triggered to adjust the straightening roller spacing. Wherein, the straightening roller group includes a coarse straightening roller group and a fine straightening roller group.

8. The TIG welding wire surface treatment method based on straightening pressure according to claim 7, characterized in that: The step of applying different gradient pressures step by step by a plurality of staggered straightening roller groups in the roller-type straightening device includes: The coarse straightening rollers in the roller-type straightening equipment are used to apply high pressure to eliminate the large curvature of the welding wire, and the pressure direction of the coarse straightening rollers is vertically staggered; The fine-adjusting straightening roller group in the roller-type straightening equipment is switched to low pressure, and the pressure direction of the fine-adjusting straightening roller group applying low pressure is horizontally staggered.

9. The TIG welding wire surface treatment method based on straightening pressure according to claim 8, characterized in that: The comparing the axial stress change with a preset threshold value, and triggering the wire springback compensation algorithm to adjust the straightening roller spacing if the axial stress change is greater than the preset threshold value, includes: Compare the axial stress change with a preset threshold value, and if the axial stress change is greater than the preset threshold value, reduce the hydraulic pressure of the straightening roller group proportionally; The hydraulic pressure of the straightening roller group after reduction and the elastic modulus of the welding wire are input into the predefined welding wire springback compensation model to calculate the welding wire springback compensation amount, and the spacing of the straightening roller group is compensated according to the welding wire springback compensation amount; After the straightening roller group spacing is compensated, the axial stress change is re-detected and compared with the preset threshold value for a second time. If it is less than or equal to the preset threshold value, it indicates that the compensation is successful. Otherwise, the compensation amount is increased by 10% through secondary compensation, and the pressure of the straightening roller group is extended for 3 seconds.

10. The TIG welding wire surface treatment method based on straightening pressure according to claim 9, characterized in that: The proportional reduction of the hydraulic pressure of the straightening roller group comprises: Reduce the pressure of the coarse straightening roller group from 15MPa to 12MPa, and reduce the pressure of the fine straightening roller group from 8MPa to 6.4MPa.

Images