A flux and welding method suitable for welding anode aluminum guide rod and anode steel claw

Abstract

The present invention provides a flux suitable for welding an anode aluminum guide rod and an anode steel claw. The flux is composed, by weight, of 40% to 75% potassium fluoroaluminate, 20% to 40% zinc powder, and 2% to 20% superheating agent. The superheating agent is composed of 40% to 70% aluminum powder, 20% to 45% zinc oxide, and 5% to 20% barite powder. The present invention also provides a welding method, which includes first applying the flux to the surface of the anode steel claw to form a flux layer. Then, using aluminum-silicon welding wire and then pure aluminum welding wire, a first layer of weld metal and a second layer of weld metal are formed on the surface of the anode steel claw. Finally, the second layer of weld metal is welded to the anode aluminum guide rod using the pure aluminum welding wire. The anode conductive device produced by the present invention has only a single weld between the anode aluminum guide rod and the anode steel claw, significantly reducing the resistance of the transition surface and increasing the tensile strength of the transition surface. The method also features a simple manufacturing process, low energy consumption, and low cost during welding, promising broad prospects for promotion and application.

Description

Technical Field

[0001] The invention belongs to the technical field of nonferrous metal metallurgy, and particularly relates to a flux suitable for welding an anode aluminum guide rod and an anode steel claw, and also relates to a welding method suitable for welding an anode aluminum guide rod and an anode steel claw. Background Art

[0002] For most domestic 200KA-600KA electrolytic aluminum manufacturers currently using prebaked anodes, the anode conductive assembly consists of an aluminum anode guide rod and a steel anode claw. The anode assembly operates in a high-temperature, highly corrosive environment, requiring it to conduct high currents while also withstanding the weight loads of the steel claw and carbon block. Therefore, the performance requirements of the aluminum-steel joint are extremely high. Directly welding the aluminum anode guide rod to the anode claw can easily lead to the formation of brittle intermetallic compounds, significantly reducing joint strength, shortening the service life of the anode claw, and increasing production costs. Therefore, in the aluminum industry, the aluminum anode guide rod and the anode claw are often connected using an aluminum-steel explosive block transition method. Specifically, the aluminum side of the aluminum-steel explosive block is welded to the aluminum guide rod, and the steel side of the aluminum-steel explosive block is welded to the anode claw along the entire contact area. This effectively avoids the formation of brittle iron-aluminum intermetallic compounds that occur when welding aluminum to steel directly. However, the expansion coefficients of aluminum and steel are quite different. Under the action of high temperature and large current, shear force is generated at the joints of the explosive blocks, causing cracks in the weld surface, reduced conductive area, and increased resistance, further exacerbating the fracture trend at the joint.

[0003] In order to solve this problem, the anode conductive devices for aluminum electrolysis disclosed in patents CN216304001U, CN214937862U and CN 216141636 U are composed of aluminum guide rods, anode steel claws and steel-aluminum connectors. The connection between the anode aluminum guide rods and the anode steel claws is achieved by welding the lower side of the guide rods to the aluminum rods on the upper part of the steel-aluminum connectors, and welding the upper surface of the steel claw crossbeam to the lower end face of the steel rods of the steel-aluminum connectors. From the disclosed content, it can be seen that this technical solution has the problems of complex structure and high production and manufacturing costs. The conductive area is limited by welding the aluminum rods to the side of the guide rods. In order to increase the conductive area of ​​the device, the number of steel-aluminum connectors must be increased. The steel-aluminum connectors use steel sleeves to improve strength, which makes the overall weight and size of the device too large, further increasing the difficulty of maintenance and replacement of the device, which is not conducive to enterprises reducing production costs.

[0004] Brazing is an important method for directly joining steel and aluminum. Patent CN201911251370.1, for example, discloses a process for laser brazing of dissimilar aluminum and steel with filler wire. The process involves inserting a brazing filler metal between the duplex steel and aluminum alloy at the weld interface. The filler metal is coated with a flux and then laser brazing is performed under a protective gas atmosphere, ultimately forming a steel / aluminum joint composed of an iron-aluminum-zinc phase at the brazed interface. Patent CN201210089338.X utilizes acetone to clean the surfaces of the steel and aluminum plates. A paste consisting of a mixed powder and a binder is then applied to the steel plates using a brush. After the steel plates dry, the steel and aluminum plates are joined to form a lap joint with the aluminum plate on top and the steel plate on the bottom. A MIG welder is used to weld the lap joint by melting the aluminum plate while maintaining the steel plate in a solid state, forming a self-brazing joint on the steel plate side and a fusion weld joint on the aluminum plate side. The fluxes used in these inventions are all composed of various metal powders, activators, salts, etc. such as potassium fluoroaluminate, nickel, zinc, and copper. The composition is too complex, and the material itself does not react to release heat and therefore cannot provide additional heat during welding. The protection effect is poor, and the welding quality has defects such as porosity and poor fusion. In actual production, in order to increase the heat to eliminate defects, it is often necessary to take process measures such as preheating, which increases production costs and process complexity.

[0005] Based on this, how to provide a flux with both high heat and welding performance to simplify the process flow of welding of anode aluminum guide rods and anode steel claws, reduce the energy consumption and cost of the welding process, and obtain an anode aluminum guide rod and anode steel claw welded joint with excellent comprehensive performance is a technical problem that needs to be solved urgently. Summary of the Invention

[0006] One of the purposes of the present invention is to provide a flux which has both high heat capacity and excellent welding performance and is suitable for welding anodized aluminum guide rods and anode steel claws.

[0007] The second purpose of the present invention is to provide a welding method suitable for welding anode aluminum guide rods and anode steel claws, which has a simple process flow, can reduce energy consumption and costs in the welding process, and has high weld connection strength.

[0008] The third object of the present invention is to provide an anode conductive device with a simple manufacturing process, low transition surface resistance formed by welding, and high tensile strength.

[0009] The technical solution adopted by the present invention to achieve one of the objectives is: providing a flux suitable for welding an anode aluminum guide rod and an anode steel claw, wherein the flux is composed of 40% to 75% potassium fluoroaluminate, 20% to 40% zinc powder and 2% to 20% high-temperature agent by weight; the high-temperature agent is composed of 40% to 70% aluminum powder, 20% to 45% zinc oxide and 5% to 20% barite powder by weight.

[0010] The flux provided by the present invention consists of three parts: potassium fluoroaluminate, zinc powder and a high-heat agent. Among them, after potassium fluoroaluminate melts, it reacts with the oxide on the metal surface, removes the oxide film, and exposes fresh metal, thereby improving the weldability of the welding material and the base material; the zinc in the flux melts, further promoting the wettability of the weld and the interface, alloying the interface structure, and controlling the composition and quantity of the Fe3Al intermetallic compound; the high-heat agent provides heat during the welding process, which can increase the welding heat input, and the welding process does not require preheating. At the same time, the amount of heat input increase can be adjusted according to the amount of the high-heat agent. Furthermore, the high-heat agent in the present invention consists of aluminum powder, zinc oxide powder and barite powder. Among them, aluminum powder and zinc oxide powder can provide enough heat for the welding process on the one hand, and on the other hand, the excess aluminum powder is melted and mixed with liquid potassium fluoroaluminate, spread on the surface of the base material, further promoting the film removal performance and welding performance of liquid potassium fluoroaluminate and improving arc stability. The main component of barite powder is barium sulfate, which can continue to react with aluminum powder to further release heat; the reaction products can adjust the slag composition and melting point, protect the liquid metal, and improve the purity and performance of the weld metal.

[0011] The flux provided by the present invention can enhance heat input and improve interfacial wettability. When used in the welding of anodized aluminum guide rods and anode steel claws, it can avoid welding defects such as lack of fusion caused by the heavy and bulky steel claws, resulting in welded joints with aesthetically pleasing welds, no cracks, and minimal porosity. Furthermore, the flux is simple in composition, easy to prepare, and inexpensive. It can be used with conventional welding equipment and materials without incurring additional costs, offering convenient and flexible operation and significantly reducing production costs during the electrolysis process.

[0012] Preferably, the flux is composed of 40% to 50% potassium fluoroaluminate, 40% zinc powder and 10% to 20% high temperature agent by weight; the high temperature agent is composed of 50% to 70% aluminum powder, 20% to 30% zinc oxide and 10% to 20% barite powder by weight.

[0013] Preferably, the mesh size of the potassium fluoroaluminate, zinc powder and high temperature agent is 50-500 mesh; the purity of the potassium fluoroaluminate and zinc powder is above 99%.

[0014] Preferably, the purity of aluminum powder and zinc oxide is above 99%, and the purity of barite powder is above 97%.

[0015] Preferably, the flux preparation method includes: first, uniformly mixing aluminum powder, zinc oxide, and barite powder to prepare a high-temperature agent; then, uniformly mixing the high-temperature agent with potassium fluoroaluminate and zinc powder; and then, maintaining the temperature at 180-220°C under a vacuum environment for 2-12 hours. This operation is intended to dehydrate the raw material powders and prevent defects such as pores in the weld during welding. Furthermore, the powder after the thermal insulation treatment is sealed and stored.

[0016] The technical solution adopted by the present invention to achieve the second purpose is to provide a welding method suitable for welding anodized aluminum guide rods and anode steel claws, comprising the following steps:

[0017] S1. Cleaning the surface of the anode steel claw, applying a mixture obtained by mixing the flux described in one of the objectives of the present invention with anhydrous ethanol to the surface of the anode steel claw, and drying to form a flux layer;

[0018] S2. Using MIG welding to form a first layer of weld metal on the surface of the flux layer using aluminum-silicon welding wire;

[0019] S3, using a MIG welding method to form a second layer of weld metal on the surface of the first layer of weld metal using a pure aluminum welding wire;

[0020] S4. Using MIG welding, a K-shaped or J-shaped groove is formed at the end of the anodized aluminum guide rod, and a pure aluminum welding wire is used to melt-weld the second layer of weld metal to the end.

[0021] In the aforementioned welding methods, applying flux can be done manually, while the overlay welding process and aluminum-aluminum welding can be automated and robotically produced to improve welding efficiency and facilitate mass production. The subsequent MIG welding process uses aluminum-silicon wire for the first layer of weld metal. The aluminum and silicon in the wire, when melted, form a multi-element eutectic with the zinc and other components in the flux, improving fluidity and ensuring a good welding process. The second layer of weld metal uses pure aluminum wire, which has a lower resistivity and helps improve the conductivity of the overall weld joint.

[0022] Furthermore, in step S1, the cleaning of the surface of the anode steel claw includes: firstly using a laser or a water jet to clean the surface of the anode steel claw to reveal the metallic luster.

[0023] Furthermore, in step S1, the mass ratio of the flux to anhydrous ethanol in the mixture is 1:(5-15); the purity of the anhydrous ethanol is analytical grade. Preferably, the mass ratio of the flux to anhydrous ethanol is 1:(8-12).

[0024] Furthermore, the coating method can be brushing, spraying, or other methods. Preferably, the mixture is applied to a thickness of 0.1 to 0.3 mm on the surface of the anode steel claw. The soldering layer can be dried by airing, for example, for 10 to 120 minutes.

[0025] Preferably, in step S2, the diameter of the aluminum-silicon welding wire is 0.8-1.2 mm, and the aluminum-silicon welding wire is selected from the welding wire model ER4043, and its composition is as follows by weight percentage: Si 5%, Mg≤0.10%, Fe≤0.04%, Cu≤0.05%, and Al balance.

[0026] Preferably, in step S3 and step S4, the diameter of the pure aluminum welding wire is 1.6-2.0 mm, and the pure aluminum welding wire is selected from the welding wire model ER1100, and its aluminum content is higher than 99%.

[0027] In the present invention, a thinner aluminum-silicon welding wire is first used to form the first layer of weld metal. This allows for lower welding current and heat input, reducing the severity of the steel-aluminum interface reaction, thereby reducing the formation of poorly performing iron-aluminum intermetallic compounds and improving interfacial bonding performance. The aluminum and silicon in the welding wire, along with components such as zinc in the flux, form a multicomponent eutectic when melted, enhancing fluidity and ensuring a good welding process. A thicker pure aluminum welding wire is then used to form the second layer of weld metal, improving welding efficiency. The pure aluminum also enhances the electrical conductivity of the weld. The final weld, using the same pure aluminum welding wire as the second weld metal, achieves the same results.

[0028] Preferably, in step S2, the MIG welding parameters include: welding current 60~180A, welding voltage 16~24V, and welding speed 10~20mm / s; in steps S3 and S4, the MIG welding parameters include: welding current 200~400A, welding voltage 25~32V, and welding speed 5~12mm / s.

[0029] Furthermore, the thickness of the first layer of weld metal is 0.2 to 2 mm, and the thickness of the second layer of weld metal is 1 to 4 mm. The total weld thickness achieved using the welding method provided by the present invention is approximately 6 to 16 mm, which is much smaller than the total weld thickness of 20 to 32 mm for three existing welds. This significantly reduces the overall welding pressure drop, significantly contributing to energy conservation and emission reduction.

[0030] Furthermore, the welding method further comprises: grinding and polishing the metal surfaces of each weld in the fully welded connection structure, and the obtained new anode conductive device can be put into industrial application.

[0031] The technical solution adopted by the present invention to achieve the third purpose is to provide an anode conductive device, including an anode aluminum guide rod and an anode steel claw, and the anode aluminum guide rod and the anode steel claw are connected using the welding method described in the second purpose of the present invention.

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

[0033] (1) The present invention provides a flux suitable for welding an anode aluminum guide rod and an anode steel claw, which is composed of three parts: potassium fluoroaluminate, zinc powder and a high-heat agent. The high-heat agent is composed of aluminum powder, zinc oxide and barite powder. The flux can improve the heat input performance during the welding process of the anode aluminum guide rod and the anode steel claw, and improve the wettability of the interface. It can avoid welding defects such as welding failure caused by the heavy weight and large volume of the steel claw, and obtain a weld joint with beautiful weld shape, no cracks and few pores. Furthermore, the flux has a simple composition, is easy to prepare, and has low cost. It uses conventional welding equipment and welding materials for welding, is convenient and flexible to operate, and greatly reduces the production cost during the electrolysis process.

[0034] (2) The present invention provides a welding method suitable for welding an anode aluminum guide rod to an anode steel claw. First, flux is applied to the surface of the anode steel claw, and then a first layer of weld metal and a second layer of weld metal are formed in sequence using a MIG welding method. The first layer of weld metal uses aluminum-silicon welding wire. When the aluminum and silicon in the welding wire and the zinc and other components in the flux melt, they form a multi-element eutectic, which improves fluidity and ensures a good welding process. The second layer of weld metal uses pure aluminum welding wire. Pure aluminum welding wire has a low resistivity, which helps to improve the conductivity of the overall weld joint. The above-mentioned surfacing process and aluminum-aluminum welding can be produced by automation and robots to improve welding efficiency, and are easy to implement industrial operation and mass production.

[0035] (3) Compared with the conventional connection structure formed by aluminum-steel explosive blocks, the anode conductive device produced by the present invention has only one weld between the anode aluminum guide rod and the anode steel claw, which can significantly reduce the transition surface resistance and improve the tensile strength of the transition surface. According to tests, the transition surface resistance of the anode conductive device produced by the present invention is 0.72~0.95μΩ, and the tensile strength of the transition surface is 95~120kN / cm 2 It is significantly superior to the welded steel claw structure obtained by conventional welding methods, can effectively extend the service life of the anode conductive device, and has important promotion and application prospects in the electrolytic aluminum industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Comparison diagram of welds formed by the welding method provided by an embodiment of the present invention and conventional connection using aluminum-steel explosive blocks; wherein (a) is the conventional method; (b) is the method provided by an embodiment of the present invention;

[0037] Figure 2 This is the EDS spectrum of the first layer of weld metal prepared in Example 1 of the present invention;

[0038] Figure 3 This is an EPMA surface scan of the first layer of weld metal produced in Example 1 of the present invention;

[0039] Figure 4This is the EDS spectrum of the second layer of weld metal prepared in Example 1 of the present invention;

[0040] Figure 5 This is an EPMA surface scan of the second layer of weld metal prepared in Example 1 of the present invention;

[0041] Among them, 1-anodized aluminum guide rod; 2-aluminum-steel weld; 21-aluminum guide rod explosion block weld; 22-explosion block steel claw weld; 3-anode steel claw. DETAILED DESCRIPTION

[0042] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0043] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0044] The present invention will be further described below with reference to specific examples, but they are not intended to limit the present invention.

[0045] The compositions (wt.%) of the flux and high-heat agent used in various embodiments of the present invention are shown in Table 1 below.

[0046] Table 1

[0047]

[0048] In the above table, the mesh size of each component is 50~500 mesh, among which the purity of potassium fluoroaluminate and zinc powder is above 99%, the purity of aluminum powder and zinc oxide is above 99%, and the purity of barite powder is above 97%.

[0049] Example 1

[0050] A method for welding an anodized aluminum guide rod and an anode steel claw comprises the following steps:

[0051] Step 1: Weigh the raw materials according to the formula shown in Table 1, use a powder mixer to fully mix potassium fluoroaluminate, zinc powder and high temperature agent, and then place it in a vacuum heating furnace and keep it at 200 degrees for 3 hours. After keeping it warm, take out the powder and seal it for storage.

[0052] Step 2: Before welding, clean the anode steel claw surface with a laser or water jet to reveal a metallic luster. Mix the prepared flux powder and alcohol (analytical grade) in a ratio of 1:10. Apply the flux to the anode steel claw surface using a brush to a thickness of 0.2mm. Allow to air dry for 30 minutes before beginning welding.

[0053] Step 3: Using the MIG method, with a welding current of 100A, a welding voltage of 16V, a welding speed of 18mm / s, and an aluminum-silicon welding wire of 1.2mm in diameter (model ER4043, composition: Si 5%, Mg≤0.10, Fe≤0.04, Cu≤0.05, Al balance), perform surfacing welding on the surface of the steel plate to obtain the first layer of weld metal;

[0054] Step 4: Use MIG welding method, welding current 280A, welding voltage 25V, welding speed 10mm / s, and pure aluminum welding wire with a diameter of 1.6mm (its model is: ER1100, aluminum content is higher than 99%) to perform surfacing welding on the surface of the first layer of aluminum-silicon metal to obtain the second layer of weld metal.

[0055] Step 5: Use MIG welding method, welding current 320A, welding voltage 28V, welding speed 6mm / s, J-shaped groove, and pure aluminum welding wire with a diameter of 2.0mm (its model is: ER1100, with an aluminum content higher than 99%) to melt and weld the second layer of weld metal and the lower end of the aluminum guide rod.

[0056] Step 6: Grind and polish the metal surface of the fully welded weld, and the obtained new anode conductive device can be put into industrial application.

[0057] Figure 1 Comparison diagram of the weld formed by the welding method provided by the embodiment of the present invention and the conventional welding method using aluminum-steel explosive blocks; wherein (a) is the conventional method; (b) is the method provided by the embodiment of the present invention. Figure 1 It can be seen that for the conventional connection method, the anode aluminum guide rod 1 and the aluminum steel explosion block are connected by the aluminum guide rod explosion block weld 21, and the anode steel claw 3 and the aluminum steel explosion block are connected by the explosion block steel claw weld 22, with the aluminum steel weld 2 of the explosion block in the middle, for a total of three welds. Figure 1 The welding method provided by the present invention shown in (b) ultimately forms only one weld.

[0058] Figure 2 This is the EDS spectrum of the first layer of weld metal obtained in Example 1 of the present invention. Figure 3 This is an EPMA surface scanning image of the first layer of weld metal prepared in Example 1 of the present invention. It can be seen that the first layer of weld metal is a typical aluminum-silicon composition.

[0059] Figure 4 This is the EDS spectrum of the second layer of weld metal obtained in Example 1 of the present invention. Figure 5 This is an EPMA surface scanning image of the second layer of weld metal prepared in Example 1 of the present invention. It can be seen that the second layer of weld metal is a typical pure aluminum component.

[0060] Example 2

[0061] A method for welding an anodized aluminum guide rod and an anode steel claw comprises the following steps:

[0062] Step 1: Weigh the raw materials according to the formula shown in Table 1, use a powder mixer to fully mix potassium fluoroaluminate, zinc powder and high temperature agent, and then place it in a vacuum heating furnace and keep it at 200 degrees for 2.5 hours. After keeping it warm, take out the powder and seal it for storage.

[0063] Step 2: Before welding, clean the anode steel claw surface with a laser or water jet to reveal a metallic luster. Mix the prepared flux powder and alcohol (analytical grade) in a ratio of 1:10. Apply the flux to the anode steel claw surface using a brush to a thickness of 0.3mm. Allow to air dry for 30 minutes before beginning welding.

[0064] Step 3: Using the MIG method, with a welding current of 80A, a welding voltage of 20V, a welding speed of 15mm / s, and an aluminum-silicon welding wire with a diameter of 1.2mm (model ER4043, composition: Si 5%, Mg≤0.10, Fe≤0.04, Cu≤0.05, Al balance), perform surfacing welding on the surface of the steel plate to obtain the first layer of weld metal;

[0065] Step 4: Use MIG welding method, welding current 200A, welding voltage 28V, welding speed 8mm / s, and pure aluminum welding wire with a diameter of 1.6mm (its model is: ER1100, aluminum content is higher than 99.7%) to perform surfacing welding on the surface of the first layer of aluminum-silicon metal to obtain the second layer of weld metal.

[0066] Step 5: Use MIG welding method, welding current 350A, welding voltage 32V, welding speed 5mm / s, K-type groove, and pure aluminum welding wire with a diameter of 2.0mm (its model is: ER1100, with an aluminum content higher than 99.7%) to melt weld the second layer of weld metal and the lower end of the aluminum guide rod.

[0067] Step 6: Grind and polish the metal surface of the fully welded weld, and the obtained new anode conductive device can be put into industrial application.

[0068] Example 3

[0069] A method for welding an anodized aluminum guide rod and an anode steel claw comprises the following steps:

[0070] Step 1: Weigh the raw materials according to the formula shown in Table 1, use a powder mixer to fully mix potassium fluoroaluminate, zinc powder and high temperature agent, and then place it in a vacuum heating furnace and keep it at 180 degrees for 5 hours. After keeping it warm, take out the powder and seal it for storage.

[0071] Step 2: Before welding, clean the surface of the anode steel claw using a laser or water jet to reveal a metallic sheen. Mix the prepared flux powder and alcohol (analytical grade) in a ratio of 1:8. Apply the flux to the anode steel claw surface using a brush to a thickness of 0.25mm. Allow to air dry for 45 minutes before beginning welding.

[0072] Step 3: Using the MIG method, with a welding current of 120A, a welding voltage of 20V, a welding speed of 16mm / s, and an aluminum-silicon welding wire of 1.2mm in diameter (model ER4043, composition: Si 5%, Mg≤0.10, Fe≤0.04, Cu≤0.05, Al balance), perform surfacing welding on the surface of the steel plate to obtain the first layer of weld metal;

[0073] Step 4: Use MIG welding method, welding current 300A, welding voltage 28V, welding speed 8mm / s, and pure aluminum welding wire with a diameter of 1.6mm (its model is: ER1100, aluminum content is higher than 99%) to perform surfacing welding on the surface of the first layer of aluminum-silicon metal to obtain the second layer of weld metal.

[0074] Step 5: Use MIG welding method, welding current 350A, welding voltage 32V, welding speed 6mm / s, J-shaped groove, and pure aluminum welding wire with a diameter of 2.0mm (its model is: ER1100, with an aluminum content higher than 99%) to melt and weld the second layer of weld metal and the lower end of the aluminum guide rod.

[0075] Step 6: Grind and polish the metal surface of the fully welded weld, and the obtained new anode conductive device can be put into industrial application.

[0076] Example 4

[0077] A method for welding an anodized aluminum guide rod and an anode steel claw comprises the following steps:

[0078] Step 1: Weigh the raw materials according to the formula shown in Table 1, use a powder mixer to fully mix potassium fluoroaluminate, zinc powder and high temperature agent, and then place it in a vacuum heating furnace and keep it at 220 degrees for 2 hours. After keeping it warm, take out the powder and seal it for storage.

[0079] Step 2: Before welding, clean the anode steel claw surface with a laser or water jet to reveal a metallic luster. Mix the prepared flux powder and alcohol (analytical grade) in a ratio of 1:12. Apply the flux to the anode steel claw surface using a brush to a thickness of 0.3mm. Allow to air dry for 30 minutes before beginning welding.

[0080] Step 3: Using the MIG method, with a welding current of 80A, a welding voltage of 16V, a welding speed of 20mm / s, and an aluminum-silicon welding wire of 1.2mm in diameter (model ER4043, composition: Si 5%, Mg≤0.10, Fe≤0.04, Cu≤0.05, Al balance), perform surfacing welding on the surface of the steel plate to obtain the first layer of weld metal;

[0081] Step 4: Use MIG welding method, welding current 260A, welding voltage 26V, welding speed 7mm / s, and pure aluminum welding wire with a diameter of 1.6mm (its model is: ER1100, aluminum content is higher than 99%) to perform surfacing welding on the surface of the first layer of aluminum-silicon metal to obtain the second layer of weld metal.

[0082] Step 5: Use MIG welding method, welding current 340A, welding voltage 30V, welding speed 6mm / s, K-type groove, and pure aluminum welding wire with a diameter of 2.0mm (its model is: ER1100, with an aluminum content higher than 99%) to melt and weld the second layer of weld metal and the lower end of the aluminum guide rod.

[0083] Step 6: Grind and polish the metal surface of the fully welded weld, and the obtained new anode conductive device can be put into industrial application.

[0084] Example 5

[0085] A method for welding an anodized aluminum guide rod and an anode steel claw comprises the following steps:

[0086] Step 1: Weigh the raw materials according to the formula shown in Table 1, use a powder mixer to fully mix potassium fluoroaluminate, zinc powder and high temperature agent, and then place it in a vacuum heating furnace and keep it at 200 degrees for 3 hours. After keeping it warm, take out the powder and seal it for storage.

[0087] Step 2: Before welding, clean the surface of the anode steel claw using a laser or water jet to reveal a metallic luster. Mix the prepared flux powder and alcohol (analytical grade) in a ratio of 1:8. Apply the flux to the anode steel claw surface using a brush to a thickness of 0.2mm. Allow to air dry for 30 minutes before beginning welding.

[0088] Step 3: Using the MIG method, with a welding current of 140A, a welding voltage of 22V, a welding speed of 16mm / s, and an aluminum-silicon welding wire of 1.2mm in diameter (model ER4043, composition: Si 5%, Mg≤0.10, Fe≤0.04, Cu≤0.05, Al balance), perform surfacing welding on the surface of the steel plate to obtain the first layer of weld metal;

[0089] Step 4: Use MIG welding method, welding current 320A, welding voltage 26V, welding speed 12mm / s, and pure aluminum welding wire with a diameter of 1.6mm (its model is: ER1100, aluminum content is higher than 99%) to perform surfacing welding on the surface of the first layer of aluminum-silicon metal to obtain the second layer of weld metal.

[0090] Step 5: Use MIG welding method, welding current 360A, welding voltage 32V, welding speed 5mm / s, J-shaped groove, and pure aluminum welding wire with a diameter of 2.0mm (its model is: ER1100, with an aluminum content higher than 99%) to melt and weld the second layer of weld metal and the lower end of the aluminum guide rod.

[0091] Step 6: Grind and polish the metal surface of the fully welded weld, and the obtained new anode conductive device can be put into industrial application.

[0092] Application performance testing

[0093] The application performance tests were conducted on the novel anode conductive devices prepared in each embodiment, and an anode conductive device prepared using a conventional connection method (aluminum-steel explosive block) was used as a control group. The relevant test results are shown in Table 2 below:

[0094] Table 2

[0095]

[0096] As can be seen from the above table,

[0097] The connection structure between the anode steel claw and the anode aluminum guide rod formed by the flux and welding method provided by the present invention has only one weld seam. Compared with the connection structure obtained by conventional welding methods, it can significantly reduce the transition surface resistance and improve the tensile strength of the transition surface, thereby effectively extending the service life of the anode conductive device.

[0098] The above are only preferred embodiments of the present invention and do not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of the present invention specification should be included in the protection scope of the present invention.

Claims

1. A flux suitable for welding anodized aluminum guide rods and anode steel claws, characterized in that: The soldering flux is composed of 40% to 75% potassium fluoroaluminate, 20% to 40% zinc powder and 2% to 20% high temperature agent in terms of weight percentage; The high-heat agent consists of 40% to 70% aluminum powder, 20% to 45% zinc oxide, and 5% to 20% barite powder in terms of weight percentage.

2. The flux suitable for welding anodized aluminum guide rods and anode steel claws according to claim 1, characterized in that: The mesh numbers of potassium fluoroaluminate, zinc powder and high-temperature agent are 50-500 meshes; the purity of potassium fluoroaluminate and zinc powder is above 99%.

3. The flux suitable for welding anodized aluminum guide rods and anode steel claws according to claim 1, characterized in that: The purity of aluminum powder and zinc oxide is above 99%, and the purity of barite powder is above 97%.

4. The flux suitable for welding anodized aluminum guide rods and anode steel claws according to claim 1, characterized in that: The preparation method of the soldering flux comprises: firstly uniformly mixing aluminum powder, zinc oxide and barite powder to prepare a high-temperature agent, then uniformly mixing the high-temperature agent with potassium fluoroaluminate and zinc powder, and keeping the mixture at 180-220° C. for 2-12 hours in a vacuum environment.

5. A welding method suitable for welding anodized aluminum guide rods and anode steel claws, characterized in that: The following steps are involved: S1. Cleaning the surface of the anode steel claw, applying a mixture obtained by mixing the flux according to any one of claims 1 to 4 with anhydrous ethanol to the surface of the anode steel claw, and forming a flux layer after drying; S2. Using MIG welding to form a first layer of weld metal on the surface of the flux layer using aluminum-silicon welding wire; S3, using a MIG welding method to form a second layer of weld metal on the surface of the first layer of weld metal using a pure aluminum welding wire; S4. Using MIG welding, a K-shaped or J-shaped groove is formed at the end of the anodized aluminum guide rod, and a pure aluminum welding wire is used to melt-weld the second layer of weld metal to the end.

6. The welding method according to claim 5, characterized in that In step S1, the mass ratio of the flux to the anhydrous ethanol is 1:(5-15); and the coating thickness of the mixture on the surface of the anode steel claw is 0.1-0.3 mm.

7. The welding method according to claim 5, characterized in that In step S2, the diameter of the aluminum-silicon welding wire is 0.8-1.2 mm; in steps S3 and S4, the diameter of the pure aluminum welding wire is 1.6-2.0 mm.

8. The welding method according to claim 5, characterized in that In step S2, the MIG welding parameters include: welding current 60-180A, welding voltage 16-24V, and welding speed 10-20mm / s; in steps S3 and S4, the MIG welding parameters include: welding current 200-400A, welding voltage 25-32V, and welding speed 5-12mm / s.

9. The welding method according to claim 5, characterized in that: The thickness of the first layer of weld metal is 0.2-2 mm, and the thickness of the second layer of weld metal is 1-4 mm.

10. An anode conductive device, comprising an anode aluminum guide rod and an anode steel claw, characterized in that: The anodized aluminum guide rod and the anode steel claw are connected by the welding method according to any one of claims 5-9.

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