High-strength corrosion-resistant flux-cored wire and method for manufacturing the same

Abstract

The application discloses a kind of high-strength corrosion-resistant flux-cored wire and preparation method thereof, it is related to welding wire technical field.The application uses potassium hexatitanate whisker as carrier, carbon nanotube, silicon carbide, rare earth metal oxide are deposited on the surface in turn, can improve weld strength, refine grain;Then the surface is fluorinated, it is favorable to improve the strength of welding wire;Then the core, composite whisker is wrapped in titanium shell, by first drawing, forms nail boundary, improves the strength of welding wire, then titanium shell, nano copper powder are modified in turn, can be mutually electrostatic adsorption, form nano copper layer, improve the conductivity and rust prevention ability of welding wire surface, then carry out second drawing treatment, make nano copper powder further embed in titanium shell, improve the conductivity and corrosion resistance effect of welding wire.The flux-cored wire prepared by the application has the effects of high strength, corrosion resistance and conductivity.

Description

Technical Field

[0001] This invention relates to the field of welding wire technology, specifically to a high-strength, corrosion-resistant flux-cored welding wire and its preparation method. Background Technology

[0002] Flux-cored welding wire is made by wrapping flux powder inside a thin steel strip and rolling it into different cross-sectional shapes, or by rolling a coil into a "U" shape, filling the flux powder into a groove, and then processing it through rolling and drawing. Compared with solid welding wire, flux-cored welding wire has the following characteristics: it is suitable for welding various types of steel, has good process performance, fast deposition speed, and can be used for all-position welding with a larger welding current.

[0003] In welding, the welding wire material determines the welding quality and efficiency, and plays a crucial role in the strength of the welded metal. Furthermore, to prevent corrosion and rust on the welding wire surface, the traditional method is to copper-plat it. However, the wastewater and slag generated during the traditional copper plating process pose a significant threat to the already fragile natural environment, which is inconsistent with the national advocacy of "sustainable development" and "green economy." Additionally, the welding wire uses a titanium tube shell, but the poor conductivity of titanium severely affects the welding quality. Therefore, this invention treats the titanium tube shell to make it conductive and corrosion-resistant, and uses composite whiskers as the main raw material for the flux core, which effectively improves the strength of the welding wire. Summary of the Invention

[0004] The purpose of this invention is to provide a high-strength, corrosion-resistant flux-cored welding wire and its preparation method, so as to solve the problems existing in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a high-strength corrosion-resistant flux-cored welding wire, wherein the high-strength corrosion-resistant flux-cored welding wire comprises a composite titanium tube, flux powder, and composite whiskers.

[0006] Furthermore, the composite titanium tube is obtained by secondary modification and drawing treatment of titanium tube.

[0007] Furthermore, the first modification treatment involves mixing anhydrous ethanol and distilled water, heating the mixture in a water bath to a certain temperature, adding bromobutyltrimethoxysilane and nano copper powder, reacting for a period of time, removing, washing, and drying to obtain pre-modified copper powder; the second modification treatment involves mixing the pre-modified copper powder and triethylamine, heating and reacting the mixture, adding petroleum ether, stirring, filtering, immersing in an ethanol / ethyl acetate solution, filtering, and drying to obtain modified copper powder.

[0008] Furthermore, the core powder is composed of aluminum oxide, ferric oxide, magnesium carbonate, nickel, manganese, boron, and tungsten powder.

[0009] Furthermore, the composite whiskers are prepared by the following method: using potassium hexatitanate whiskers as a carrier, carbon nanotube whiskers are electrodeposited; silicon carbide whiskers are obtained by vapor deposition in a mixed atmosphere; rare earth whiskers are obtained by plasma-assisted laser deposition of silicon carbide whiskers in a pulsed laser device; and the rare earth whiskers are modified by plasma fluorination to obtain composite whiskers.

[0010] Furthermore, a method for preparing a high-strength, corrosion-resistant flux-cored welding wire includes the following preparation steps:

[0011] (1) Mix aluminum oxide, ferric oxide, magnesium carbonate, nickel, manganese, boron and tungsten powder in a mass ratio of 5:5:1:8:2:0.2 to 10:10:8:11:5:0.5 and grind to 200 mesh to obtain core powder; mix core powder and composite whiskers in a mass ratio of 1:0.6 to 1:1.2, stir at 1000 rpm for 3 to 8 minutes, fill titanium tube, seal both ends of titanium tube, draw wire to 1.4 to 2.0 mm, anneal at 630 to 650℃ for 45 to 53 minutes to obtain welding wire blank;

[0012] (2) Mix the welding wire blank and deionized water at a mass ratio of 1:1000, sonicate at 100W for 1 to 3 hours, add 50 to 60 times the mass of the welding wire blank and 40 to 50 times the mass of the welding wire blank, mix evenly, continue sonicating for 2 to 4 hours, filter, and dry at 65℃ for 24 hours to obtain carboxylated welding wire blank;

[0013] (3) Mix pre-modified copper powder and triethylamine at a mass ratio of 1:1.5 to 1:2.0, heat to 80°C, react for 40 to 44 hours, add petroleum ether at a mass ratio of 1.2 to 1.8 times that of the pre-modified copper powder, stir at 80 rpm for 30 to 40 minutes, filter, soak in an ethanol / ethyl acetate solution at a mass ratio of 3 to 6 times that of the pre-modified copper powder, where the mass ratio of anhydrous ethanol to ethyl acetate in the ethanol / ethyl acetate solution is 1.75:1, soak for 1 to 2 hours, filter, and dry at 55°C for 18 hours to obtain modified copper powder;

[0014] (4) Mix modified copper powder, polyethylene glycol 2000 and polyethylene wax in a mass ratio of 100:1:1 to 100:5:1, heat to 92°C, keep warm for 1 to 2 hours, spray onto carboxylated welding wire blank to a thickness of 20 to 30 μm, dry at 60°C for 40 hours, draw to 0.8 to 1.2 mm, and anneal at 630 to 650°C for 45 to 53 minutes to obtain high-strength corrosion-resistant flux-cored welding wire.

[0015] Furthermore, the method for preparing the composite whiskers in step (1) is as follows:

[0016] A. Using a stainless steel plate as the cathode and potassium hexatitanate whiskers as the anode, with a plate distance of 20 mm and an electrodeposition voltage of 60 V for 40-58 min, carbon nanotube whiskers are obtained by extraction with distilled water for 24 h and drying at 48 °C for 12 h.

[0017] B. Place carbon nanotube whiskers in a deposition chamber and deposit them for 1 to 2 hours at 1050–1100℃ and 200–300Pa in a mixed atmosphere. Then, rotate the whiskers 180° and continue to deposit for 1 to 2 hours to obtain silicon carbide whiskers.

[0018] C. Place the silicon carbide whiskers in a pulsed laser device and evacuate to a vacuum level of 1×10⁻⁶. -4 At a pressure of 3 × 10⁻⁶ Pa, argon and oxygen are introduced at a flow ratio of 10:1 until the pressure reaches 3 × 10⁻⁶ Pa. -2 Pa, using a lanthanum target, with a laser wavelength of 532 nm, a pulse width of 5 ns, a repetition frequency of 10 Hz, and a laser energy density of 1 J / cm². 2 Rare earth whiskers were obtained by deposition at a radio frequency power of 60W for 52–68 minutes.

[0019] D. Place rare earth whiskers in a plasma device and modify them for 6-12 minutes under an argon / carbon tetrafluoride atmosphere at a voltage of 10kV and a discharge frequency of 50kHz. The flow ratio of argon to carbon tetrafluoride in the argon / carbon tetrafluoride atmosphere is 10:1 to obtain composite whiskers.

[0020] Furthermore, the electrodeposition solution preparation method used in step A is as follows: carbon nanotubes, hexadecyltrimethylammonium bromide, and deionized water are mixed in a mass ratio of 0.05:0.03:99 to 0.2:0.03:99 and ultrasonically dispersed at 100W for 1 to 3 hours.

[0021] Furthermore, the mixed atmosphere described in step B is hydrogen, argon, and methyltrichlorosilane in a flow rate ratio of...

[0022] Mix 1:2.5:0.04 to 1:2.5:0.2.

[0023] Further, the preparation method of the pre-modified copper powder in step (3) is as follows: anhydrous ethanol and distilled water are mixed at a mass ratio of 7.1:1, heated in a water bath to 50°C, and 0.08 to 0.3 times the mass of distilled water of bromobutyltrimethoxysilane and 0.04 to 0.3 times the mass of distilled water of nano-copper powder are added. After reacting for 2 to 4 hours, the mixture is taken out and washed with anhydrous ethanol and distilled water 3 to 5 times in sequence, and then dried at 60°C for 12 hours to obtain the pre-modified copper powder.

[0024] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0025] This invention encapsulates powdered drug cores and composite whiskers within a titanium shell, and then performs secondary drawing and secondary modification treatments to achieve high strength, corrosion resistance, and electrical conductivity.

[0026] First, this invention uses potassium hexatitanate whiskers as a carrier for a first deposition process, where a carbon nanotube film is deposited on the whisker surface using electrophoretic deposition. Then, a second deposition process is performed using vapor deposition. The carbon nanotubes provide numerous active sites for silicon carbide deposition, allowing methyltrichlorosilane to adsorb onto the carbon nanotubes, aggregate around them, and nucleate and grow, thus forming silicon carbide. This improves weld strength, inhibits excessive grain growth during heat treatment, refines grains, reduces oxides in the weld, purifies grain boundaries, and helps improve weld wire strength. A third deposition process is then performed. The process involves using a laser to deposit a layer of rare-earth metal lanthanum on the surface. During deposition, the lanthanum combines with oxygen plasma in the air to form rare-earth metal oxides. This reduces the diffusive hydrogen in the weld metal, refines the grain size, and improves the strength of the welding wire. Furthermore, the lanthanum oxides have a strong affinity for impurity elements, altering the shape, quantity, and distribution of inclusions and reducing their detrimental effects on strength. The surface rare-earth metal oxides are then fluorinated, causing the composite whiskers to react with water vapor in the flux core to generate gases such as hydrogen fluoride. This reduces the diffusive hydrogen in the weld, further enhancing the strength of the welding wire.

[0027] Secondly, this invention encapsulates powdered flux cores and composite whiskers within a corrosion-resistant titanium shell, enhancing the welding wire's corrosion resistance. The first drawing process creates studded grain boundaries on the titanium shell surface, refining the grains and increasing the welding wire's strength. A first modification treatment is then performed, using chloroacetic acid to acidify the titanium shell, imbuing it with carboxyl groups. A second modification treatment follows, using bromobutyltrimethoxysilane to modify the nano-copper powder, grafting it onto the nano-copper powder surface. Bromine ions react with the amino groups of triethylamine to form a positively charged quaternary ammonium structure, which electrostatically adsorbs onto the negatively charged titanium shell surface, forming a nano-copper layer. This improves the welding wire's conductivity and rust resistance. A second drawing process then fuses the nano-copper powder with the titanium shell, further embedding it within the shell and enhancing the welding wire's conductivity and corrosion resistance. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0029] To more clearly illustrate the method provided by the present invention, the following embodiments are provided in detail. The test methods for various indicators of the high-strength corrosion-resistant flux-cored welding wire produced in the following embodiments are as follows:

[0030] High strength: Two pieces of Q690 grade structural steel were welded in a carbon dioxide atmosphere with a welding current of 200A, a welding voltage of 25V, a welding speed of 0.2m / min, and a gas flow rate of 20L / min. The mechanical properties were then tested in accordance with GB / T 25774.1.

[0031] Conductivity: Volume resistivity of identically sized examples and comparative examples was measured using a resistivity meter.

[0032] Corrosion resistance: Samples of the same size as the comparative example were placed in a constant temperature and humidity chamber at 40°C and 60% for 168 hours, and the surface corrosion was observed.

[0033] Example 1

[0034] (1) Carbon nanotubes, hexadecyltrimethylammonium bromide and deionized water were mixed in a mass ratio of 0.05:0.03:99 and ultrasonically dispersed at 100W for 1h to obtain carbon nanotube plating solution; stainless steel plate was used as cathode and potassium hexatitanate whiskers were used as anode. In the carbon nanotube plating solution, the distance between the plates was 20mm and the voltage was 60V for 40min. After that, the carbon nanotubes were extracted with distilled water for 24h and dried at 48℃ for 12h to obtain carbon nanotube whiskers.

[0035] (2) Carbon nanotube whiskers were placed in a deposition chamber and deposited at 1050℃ and 200Pa for 1 hour in a mixed atmosphere. Then, the whiskers were rotated 180° and deposited for another hour to obtain silicon carbide whiskers. The flow rate ratio of hydrogen, argon and methyltrichlorosilane in the mixed atmosphere was 1:2.5:0.04.

[0036] (3) Place the silicon carbide whiskers in a pulsed laser device and evacuate to 1×10⁻⁶. -4 At a pressure of 3 × 10 Pa, argon and oxygen are introduced at a flow ratio of 10:1 until the pressure reaches 3 × 10 Pa. -2 Pa, using a lanthanum target, with a laser wavelength of 532 nm, a pulse width of 5 ns, a repetition frequency of 10 Hz, and a laser energy density of 1 J / cm². 2 Rare earth whiskers were obtained by deposition at a radio frequency power of 60W for 52 minutes.

[0037] (4) The rare earth whiskers were placed in a plasma device and modified for 6 minutes under an argon / carbon tetrafluoride atmosphere with a voltage of 10kV and a discharge frequency of 50kHz. The flow ratio of argon to carbon tetrafluoride in the argon / carbon tetrafluoride atmosphere was 10:1 to obtain composite whiskers.

[0038] (5) Mix aluminum oxide, ferric oxide, magnesium carbonate, nickel, manganese, boron and tungsten powder in a mass ratio of 5:5:1:8:2:0.2 and grind to 200 mesh to obtain core powder; mix core powder and composite whiskers in a mass ratio of 1:0.6, stir at 1000 rpm for 3 min, fill titanium tube, seal both ends of titanium tube, draw wire to 1.4 mm, anneal at 630~650℃ for 45 min to obtain welding wire blank;

[0039] (6) Mix the welding wire blank and deionized water at a mass ratio of 1:1000, sonicate at 100W for 1 hour, add 50 times the mass of the welding wire blank sodium hydroxide and 40 times the mass of the welding wire blank monochloroacetic acid, mix evenly, continue sonicating for 2 hours, filter, and dry at 65℃ for 24 hours to obtain carboxylated welding wire blank.

[0040] (7) Mix anhydrous ethanol and distilled water at a mass ratio of 7.1:1, heat in a water bath to 50°C, add 0.08 times the mass of distilled water of bromobutyltrimethoxysilane and 0.04 times the mass of distilled water of nano copper powder, react for 2 hours, take out, wash with anhydrous ethanol and distilled water three times in sequence, and dry at 60°C for 12 hours to obtain pre-modified copper powder;

[0041] (8) Mix pre-modified copper powder and triethylamine at a mass ratio of 1:1.5, heat to 80°C, react for 40 h, add petroleum ether at a mass ratio of 1.2 times that of the pre-modified copper powder, stir at 80 rpm for 30 min, filter, soak in an ethanol / ethyl acetate solution at a mass ratio of 3 times that of the pre-modified copper powder, the mass ratio of anhydrous ethanol to ethyl acetate in the ethanol / ethyl acetate solution is 1.75:1, soak for 1 h, filter, dry at 55°C for 18 h to obtain modified copper powder;

[0042] (9) Mix modified copper powder, polyethylene glycol 2000 and polyethylene wax in a mass ratio of 100:1:1, heat to 92°C, keep warm for 1 hour, spray onto carboxylated welding wire blank to a thickness of 20 μm, dry at 60°C for 40 hours, draw to 0.8 mm, and anneal at 630°C for 45 minutes to obtain high-strength corrosion-resistant flux-cored welding wire.

[0043] Example 2

[0044] (1) Carbon nanotubes, hexadecyltrimethylammonium bromide and deionized water were mixed in a mass ratio of 0.13:0.03:99 and ultrasonically dispersed at 100W for 2h to obtain carbon nanotube plating solution; stainless steel plate was used as cathode and potassium hexatitanate whiskers were used as anode. In the carbon nanotube plating solution, the distance between the plates was 20mm and the voltage was 60V for 49min. After that, the carbon nanotubes were extracted with distilled water for 24h and dried at 48℃ for 12h to obtain carbon nanotube whiskers.

[0045] (2) Carbon nanotube whiskers were placed in a deposition chamber and deposited at 1075℃ and 250Pa for 1.5h in a mixed atmosphere. Then, the whiskers were rotated 180° and deposited for another 1.5h to obtain silicon carbide whiskers. The flow rate ratio of hydrogen, argon and methyltrichlorosilane in the mixed atmosphere was 1:2.5:0.12.

[0046] (3) Place the silicon carbide whiskers in a pulsed laser device and evacuate to 1×10⁻⁶. -4 At a pressure of 3 × 10 Pa, argon and oxygen are introduced at a flow ratio of 10:1 until the pressure reaches 3 × 10 Pa. -2 Pa, using a lanthanum target, with a laser wavelength of 532 nm, a pulse width of 5 ns, a repetition frequency of 10 Hz, and a laser energy density of 1 J / cm². 2 Rare earth whiskers were obtained by deposition at a radio frequency power of 60W for 60 minutes.

[0047] (4) The rare earth whiskers were placed in a plasma device and modified for 9 minutes under an argon / carbon tetrafluoride atmosphere with a voltage of 10kV and a discharge frequency of 50kHz. The flow ratio of argon to carbon tetrafluoride in the argon / carbon tetrafluoride atmosphere was 10:1 to obtain composite whiskers.

[0048] (5) Mix aluminum oxide, ferric oxide, magnesium carbonate, nickel, manganese, boron and tungsten powder in a mass ratio of 7.5:7.5:4.5:9.5:3.5:0.35, grind to 200 mesh to obtain core powder; mix core powder and composite whiskers in a mass ratio of 1:0.9, stir at 1000 rpm for 5 min, fill titanium tube, seal both ends of titanium tube, draw wire to 1.7 mm, anneal at 640℃ for 49 min to obtain welding wire blank;

[0049] (6) Mix the welding wire blank and deionized water at a mass ratio of 1:1000, sonicate at 100W for 2 hours, add sodium hydroxide at 55 times the mass of the welding wire blank and monochloroacetic acid at 45 times the mass of the welding wire blank, mix evenly, continue sonicating for 3 hours, filter, and dry at 65℃ for 24 hours to obtain carboxylated welding wire blank.

[0050] (7) Mix anhydrous ethanol and distilled water at a mass ratio of 7.1:1, heat in a water bath to 50°C, add 0.19 times the mass of distilled water of bromobutyltrimethoxysilane and 0.17 times the mass of distilled water of nano copper powder, react for 3 hours, take out, wash with anhydrous ethanol and distilled water 4 times in sequence, and dry at 60°C for 12 hours to obtain pre-modified copper powder;

[0051] (8) Mix pre-modified copper powder and triethylamine at a mass ratio of 1:1.8, heat to 80°C, react for 42 hours, add petroleum ether at a mass ratio of 1.5 times that of the pre-modified copper powder, stir at 80 rpm for 35 minutes, filter, soak in an ethanol / ethyl acetate solution at a mass ratio of 4.5 times that of the pre-modified copper powder, where the mass ratio of anhydrous ethanol to ethyl acetate in the ethanol / ethyl acetate solution is 1.75:1, soak for 1.5 hours, filter, and dry at 55°C for 18 hours to obtain modified copper powder;

[0052] (9) Mix modified copper powder, polyethylene glycol 2000 and polyethylene wax in a mass ratio of 100:3:1, heat to 92°C, keep warm for 1.5h, spray onto carboxylated welding wire blank to a thickness of 25μm, dry at 60°C for 40h, draw to 1.0mm, anneal at 640°C for 49min to obtain high-strength corrosion-resistant flux-cored welding wire.

[0053] Example 3

[0054] (1) Carbon nanotubes, hexadecyltrimethylammonium bromide and deionized water were mixed in a mass ratio of 0.2:0.03:99 and ultrasonically dispersed at 100W for 3h to obtain carbon nanotube plating solution; stainless steel plate was used as cathode and potassium hexatitanate whiskers were used as anode. In the carbon nanotube plating solution, the distance between the plates was 20mm and the voltage was 60V for 58min. After that, the carbon nanotubes were extracted with distilled water for 24h and dried at 48℃ for 12h to obtain carbon nanotube whiskers.

[0055] (2) Carbon nanotube whiskers were placed in a deposition chamber and deposited at 1100℃ and 300Pa for 2 hours in a mixed atmosphere. Then, the whiskers were rotated 180° and deposited for another 2 hours to obtain silicon carbide whiskers. The flow rate ratio of hydrogen, argon and methyltrichlorosilane in the mixed atmosphere was 1:2.5:0.2.

[0056] (3) Place the silicon carbide whiskers in a pulsed laser device and evacuate to 1×10⁻⁶. -4 At a pressure of 3 × 10 Pa, argon and oxygen are introduced at a flow ratio of 10:1 until the pressure reaches 3 × 10 Pa. -2 Pa, using a lanthanum target, with a laser wavelength of 532 nm, a pulse width of 5 ns, a repetition frequency of 10 Hz, and a laser energy density of 1 J / cm². 2 Rare earth whiskers were obtained by deposition at a radio frequency power of 60W for 68 minutes.

[0057] (4) The rare earth whiskers were placed in a plasma device and modified for 12 minutes under an argon / carbon tetrafluoride atmosphere with a voltage of 10kV and a discharge frequency of 50kHz. The flow ratio of argon to carbon tetrafluoride in the argon / carbon tetrafluoride atmosphere was 10:1 to obtain composite whiskers.

[0058] (5) Mix aluminum oxide, ferric oxide, magnesium carbonate, nickel, manganese, boron and tungsten powder in a mass ratio of 10:10:8:11:5:0.5 and grind to 200 mesh to obtain core powder; mix core powder and composite whiskers in a mass ratio of 1:1.2, stir at 1000 rpm for 8 min, fill titanium tube, seal both ends of titanium tube, draw wire to 2.0 mm, anneal at 650℃ for 53 min to obtain welding wire blank;

[0059] (6) Mix the welding wire blank and deionized water at a mass ratio of 1:1000, sonicate at 100W for 3 hours, add 60 times the mass of the welding wire blank sodium hydroxide and 50 times the mass of the welding wire blank monochloroacetic acid, mix evenly, continue sonicating for 4 hours, filter, and dry at 65℃ for 24 hours to obtain carboxylated welding wire blank.

[0060] (7) Mix anhydrous ethanol and distilled water at a mass ratio of 7.1:1, heat in a water bath to 50°C, add 0.3 times the mass of distilled water of bromobutyltrimethoxysilane and 0.3 times the mass of distilled water of nano copper powder, react for 4 hours, take out, wash with anhydrous ethanol and distilled water 5 times in sequence, and dry at 60°C for 12 hours to obtain pre-modified copper powder.

[0061] (8) Mix pre-modified copper powder and triethylamine at a mass ratio of 1:2, heat to 80°C, react for 44 hours, add petroleum ether at a mass ratio of 1.8 times that of the pre-modified copper powder, stir at 80 rpm for 40 minutes, filter, soak in an ethanol / ethyl acetate solution at a mass ratio of 6 times that of the pre-modified copper powder, the mass ratio of anhydrous ethanol to ethyl acetate in the ethanol / ethyl acetate solution is 1.75:1, soak for 2 hours, filter, dry at 55°C for 18 hours to obtain modified copper powder;

[0062] (9) Mix modified copper powder, polyethylene glycol 2000 and polyethylene wax in a mass ratio of 100:5:1, heat to 92°C, keep warm for 2 hours, spray onto carboxylated welding wire blank to a thickness of 30 μm, dry at 60°C for 40 hours, draw to 1.2 mm, and anneal at 650°C for 53 minutes to obtain high-strength corrosion-resistant flux-cored welding wire.

[0063] Comparative Example 1

[0064] The difference between Comparative Example 1 and Example 2 is that step (1) is omitted, and step (2) is changed to: placing potassium hexatitanate whiskers in a deposition chamber, depositing them for 1.5 h at 1075 °C and 250 Pa in a mixed atmosphere, then rotating them 180 ° and continuing to deposit them for another 1.5 h to obtain silicon carbide whiskers. The flow rate ratio of hydrogen, argon, and methyltrichlorosilane in the mixed atmosphere is 1:2.5:0.12. The remaining steps are the same as in Example 2.

[0065] Comparative Example 2

[0066] The difference between Comparative Example 2 and Example 2 is that step (2) is omitted, and step (3) is changed to: placing carbon nanotube whiskers in a pulsed laser device and evacuating to 1×10⁻⁶. -4 At a pressure of 3 × 10 Pa, argon and oxygen are introduced at a flow ratio of 10:1 until the pressure reaches 3 × 10 Pa. -2 Pa, using a lanthanum target, with a laser wavelength of 532 nm, a pulse width of 5 ns, a repetition frequency of 10 Hz, and a laser energy density of 1 J / cm². 2 Rare earth whiskers were deposited at a radio frequency power of 60W for 60 minutes. The remaining steps were the same as in Example 2.

[0067] Comparative Example 3

[0068] The difference between Comparative Example 3 and Example 2 is that step (3) is omitted, and step (4) is changed to: placing silicon carbide whiskers in a plasma device, modifying them for 9 minutes under an argon / carbon tetrafluoride atmosphere at a voltage of 10kV and a discharge frequency of 50kHz, with an argon to carbon tetrafluoride flow ratio of 10:1 to obtain composite whiskers. The remaining steps are the same as in Example 2.

[0069] Comparative Example 4

[0070] The difference between Comparative Example 4 and Example 2 is that step (4) is omitted, and step (3) is changed to: placing silicon carbide whiskers in a pulsed laser device and evacuating to 1×10⁻⁶. -4 At a pressure of 3 × 10 Pa, argon and oxygen are introduced at a flow ratio of 10:1 until the pressure reaches 3 × 10 Pa. -2 Pa, using a lanthanum target, with a laser wavelength of 532 nm, a pulse width of 5 ns, a repetition frequency of 10 Hz, and a laser energy density of 1 J / cm². 2 The composite whiskers were deposited at a radio frequency power of 60W for 60 minutes. The remaining steps were the same as in Example 2.

[0071] Comparative Example 5

[0072] The difference between Comparative Example 5 and Example 2 is that step (6) is omitted, and step (9) is changed to: mixing modified copper powder, polyethylene glycol 2000, and polyethylene wax in a mass ratio of 100:3:1, heating to 92°C, holding at that temperature for 1.5 hours, spraying the mixture onto the welding wire blank to a thickness of 25 μm, drying at 60°C for 40 hours, drawing to 1.0 mm, and annealing at 640°C for 49 minutes to obtain a high-strength corrosion-resistant flux-cored welding wire. The remaining steps are the same as in Example 2.

[0073] Comparative Example 6

[0074] The difference between Comparative Example 6 and Example 2 is that step (7) is omitted, and step (8) is changed to: mixing nano-copper powder and triethylamine at a mass ratio of 1:1.8, heating to 80°C, reacting for 42 hours, adding petroleum ether at 1.5 times the mass of nano-copper powder, stirring at 80 rpm for 35 minutes, filtering, immersing in an ethanol / ethyl acetate solution at 4.5 times the mass of nano-copper powder (the mass ratio of anhydrous ethanol to ethyl acetate in the ethanol / ethyl acetate solution is 1.75:1), immersing for 1.5 hours, filtering, and drying at 55°C for 18 hours to obtain modified copper powder. The remaining steps are the same as in Example 2.

[0075] Comparative Example 7

[0076] The difference between Comparative Example 7 and Example 2 is that step (8) is omitted, and step (7) is changed to: anhydrous ethanol and distilled water are mixed at a mass ratio of 7.1:1, heated in a water bath to 50°C, and 0.19 times the mass of distilled water of bromobutyltrimethoxysilane and 0.17 times the mass of distilled water of nano-copper powder are added. After reacting for 3 hours, the mixture is taken out, washed 4 times with anhydrous ethanol and distilled water, and then dried at 60°C for 12 hours to obtain modified copper powder. The remaining steps are the same as in Example 2.

[0077] Comparative Example 8

[0078] The difference between Comparative Example 8 and Example 2 lies in step (9). Step (9) is changed to: mixing modified copper powder, polyethylene glycol 2000, and polyethylene wax in a mass ratio of 100:3:1, heating to 92°C, holding at that temperature for 1.5 hours, and then spraying the mixture onto the carboxylated welding wire blank to a thickness of 25 μm. The mixture is then dried at 60°C for 40 hours to obtain a high-strength, corrosion-resistant flux-cored welding wire. The remaining steps are the same as in Example 2.

[0079] Example of effect

[0080] Table 1 below shows the performance analysis results of the high-strength corrosion-resistant flux-cored welding wires used in Examples 1 to 3 and Comparative Examples 1 to 8 of the present invention.

[0081] Table 1

[0082]

[0083]

[0084] A comparison of the tensile strength and yield strength experimental data of the embodiments and comparative examples shows that the present invention uses potassium hexatitanate whiskers as a carrier. Through multiple deposition processes, a layer of carbon nanotube film is first deposited on the surface of the whiskers, and silicon carbide gathers and grows around the carbon nanotubes, which can improve the weld strength, prevent excessive grain growth during heat treatment, refine the grains, reduce oxides in the weld, purify the grain boundaries, and help improve the strength of the welding wire. Then, a layer of rare earth fluoride metal oxide is deposited on the surface to further refine the grain size, while also changing the shape and number of inclusions. The distribution of impurities reduces their harmful effects on strength, thus improving the strength of the welding wire. A comparison of corrosion and volume resistivity experimental data from the examples and comparative examples reveals that the present invention uses a titanium shell to improve the corrosion resistance of the welding wire. Then, the titanium shell and nano-copper powder are modified sequentially to carry positive and negative charges respectively, causing them to electrostatically adsorb together to form a nano-copper layer. This improves the conductivity and rust prevention of the welding wire surface. Through drawing treatment, the nano-copper powder is fused with the titanium shell and further embedded within it, further enhancing the conductivity and corrosion resistance of the welding wire.

[0085] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A high-strength, corrosion-resistant flux-cored welding wire, characterized in that, The preparation steps include the following: (1) Mix aluminum oxide, ferric oxide, magnesium carbonate, nickel, manganese, and boron powder in the following mass ratios. Mix 5:5:1:8:2:0.2~10:10:8:11:5:0.5 and grind to 200 mesh to obtain core powder; mix the core powder and composite whiskers at a mass ratio of 1:0.6~1:1.2, stir at 1000 rpm for 3~8 min, fill the titanium tube, seal both ends of the titanium tube, draw the wire to 1.4~2.0 mm, anneal at 630~650℃ for 45~53 min to obtain welding wire blank; the composite whiskers are prepared by the following method: using potassium hexatitanate whiskers as a carrier, carbon nanotube whiskers are electrodeposited; silicon carbide whiskers are obtained by vapor deposition in a mixed atmosphere; rare earth whiskers are obtained by plasma-assisted laser deposition of silicon carbide whiskers in a pulsed laser device; and composite whiskers are obtained by plasma fluorination modification of rare earth whiskers. (2) Mix the welding wire blank and deionized water at a mass ratio of 1:1000, sonicate at 100W for 1 to 3 hours, add 50 to 60 times the mass of the welding wire blank and 40 to 50 times the mass of the welding wire blank, mix evenly, continue sonicating for 2 to 4 hours, filter, and dry at 65℃ for 24 hours to obtain carboxylated welding wire blank; (3) Mix pre-modified copper powder and triethylamine at a mass ratio of 1:1.5 to 1:2.0, heat to 80°C, react for 40 to 44 hours, add petroleum ether at a mass ratio of 1.2 to 1.8 times that of the pre-modified copper powder, stir at 80 rpm for 30 to 40 minutes, filter, soak in an ethanol / ethyl acetate solution at a mass ratio of 3 to 6 times that of the pre-modified copper powder, where the mass ratio of anhydrous ethanol to ethyl acetate in the ethanol / ethyl acetate solution is 1.75:1, soak for 1 to 2 hours, filter, and dry at 55°C for 18 hours to obtain modified copper powder; (4) Mix modified copper powder, polyethylene glycol 2000 and polyethylene wax in a mass ratio of 100:1:1 to 100:5:1, heat to 92°C, keep warm for 1 to 2 hours, spray onto carboxylated welding wire blank to a thickness of 20 to 30 μm, dry at 60°C for 40 hours, draw to 0.8 to 1.2 mm, and anneal at 630 to 650°C for 45 to 53 minutes to obtain high-strength corrosion-resistant flux-cored welding wire.

2. The high-strength, corrosion-resistant flux-cored welding wire according to claim 1, characterized in that, The method for preparing the composite whiskers in step (1) is as follows: A. Using a stainless steel plate as the cathode and potassium hexatitanate whiskers as the anode, with a plate distance of 20 mm and an electrodeposition voltage of 60 V for 40-58 min, carbon nanotube whiskers are obtained by extraction with distilled water for 24 h and drying at 48 °C for 12 h. B. Place carbon nanotube whiskers in a deposition chamber and deposit them for 1 to 2 hours at 1050–1100℃ and 200–300Pa in a mixed atmosphere. Then, rotate the whiskers 180° and continue to deposit for 1 to 2 hours to obtain silicon carbide whiskers. C. Place the silicon carbide whiskers in a pulsed laser device and evacuate to a vacuum level of 1×10⁻⁶. -4 At a pressure of 3 × 10 Pa, argon and oxygen are introduced at a flow ratio of 10:1 until the pressure reaches 3 × 10 Pa. -2 Pa, using a lanthanum target, with a laser wavelength of 532 nm, a pulse width of 5 ns, a repetition frequency of 10 Hz, and a laser energy density of 1 J / cm². 2 Rare earth whiskers were obtained by deposition at a radio frequency power of 60W for 52-68 minutes. D. Place rare earth whiskers in a plasma device and modify them for 6-12 minutes under an argon / carbon tetrafluoride atmosphere at a voltage of 10kV and a discharge frequency of 50kHz. The flow ratio of argon to carbon tetrafluoride in the argon / carbon tetrafluoride atmosphere is 10:1 to obtain composite whiskers.

3. The high-strength, corrosion-resistant flux-cored welding wire according to claim 2, characterized in that, The electrodeposition solution used in step A is prepared by mixing carbon nanotubes, hexadecyltrimethylammonium bromide, and deionized water in a mass ratio of 0.05:0.03:99 to 0.2:0.03:99 and ultrasonically dispersing at 100W for 1 to 3 hours.

4. The high-strength, corrosion-resistant flux-cored welding wire according to claim 2, characterized in that, The mixed atmosphere in step B is a mixture of hydrogen, argon, and methyltrichlorosilane at a flow rate ratio of 1:2.5:0.04 to 1:2.5:0.

2.

5. The high-strength, corrosion-resistant flux-cored welding wire according to claim 1, characterized in that, The preparation method of the pre-modified copper powder in step (3) is as follows: Anhydrous ethanol and distilled water are mixed at a mass ratio of 7.1:1, heated in a water bath to 50°C, and 0.08 to 0.3 times the mass of distilled water of bromobutyltrimethoxysilane and 0.04 to 0.3 times the mass of distilled water of nano-copper powder are added. After reacting for 2 to 4 hours, the mixture is taken out and washed with anhydrous ethanol and distilled water 3 to 5 times in sequence. Then, it is dried at 60°C for 12 hours to obtain the pre-modified copper powder.

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