High frequency induction brazing device for aluminum-steel dissimilar metal anode structure of electrolytic cell

Abstract

An electrolytic cell anode structure aluminum steel dissimilar metal high-frequency induction brazing device, including: connecting piece, set in the steel bar to be welded surface, the connecting piece is hollow ring structure, and the connecting piece can accommodate the insertion of the aluminum bar to be welded end; screw, provided with a plurality of, evenly fixed in the steel bar to be welded end in the form of ring array, and located in the hollow structure of the connecting piece; high-frequency electromagnetic induction heating coil, set in the steel bar and aluminum bar to be welded area side, for heating the steel bar and aluminum bar, wherein, the steel bar and aluminum bar to be welded end, the connecting piece inside and the aluminum bar between the side are provided with aluminum-based filler layer.

Description

Technical Field

[0001] This application relates to the field of aluminum / steel dissimilar metal welding technology, and more particularly to a high-frequency induction brazing device for aluminum / steel dissimilar metals with an anode structure in an electrolytic cell. Background Technology

[0002] With the development of the electrolytic aluminum industry, the joining technology of aluminum / steel dissimilar metals in the anode structure of electrolytic cells has become a key factor affecting electrolysis efficiency and equipment operational stability. However, aluminum and steel have significantly different physicochemical properties, with melting points differing by about 800℃ and thermal expansion coefficients differing by more than 2 times. Furthermore, their metallurgical compatibility is extremely poor. Direct welding easily leads to the formation of brittle Fe-Al intermetallic compounds Fe2Al5 and FeAl3 at the interface, resulting in low joint strength and easy cracking, which severely restricts the high-performance joining of dissimilar materials.

[0003] Traditional welding methods such as fusion welding and arc welding face challenges: premature melting of aluminum and insufficient melting of steel during fusion welding can easily lead to an excessively thick interfacial IMC (Intermetallic Compound) layer; although low-temperature brazing can inhibit IMC growth, it has problems such as poor wettability and insufficient joint strength. Utility Model Content

[0004] The embodiments of this application provide a high-frequency induction brazing device for aluminum-steel dissimilar metals in an electrolytic cell anode structure. This device can significantly reduce the resistivity at the connection between the aluminum anode guide rod and the steel claw, improve conductivity and structural strength, and further improve the efficiency of fusion brazing while reducing equipment investment costs.

[0005] The embodiments of this application employ the following technical solutions:

[0006] In a first aspect, embodiments of this application provide a method for high-frequency induction brazing of dissimilar metals, aluminum and steel, in an electrolytic cell anode structure. The method includes: setting an internally hollow annular connector at the end of the steel rod to be welded, the connector being able to accommodate the insertion of the end of the aluminum rod to be welded; performing deoxidation and sandblasting treatment on the areas to be welded of the steel and aluminum rods and the connector; after fixing multiple screws to the treated end of the steel rod to be welded, placing aluminum-based brazing filler metal inside the connector, wherein the aluminum-based brazing filler metal includes Al, Cu, Mg, Si, La, and Ce metal elements; after inserting the end of the aluminum rod to be welded into the connector, arranging high-frequency electromagnetic induction heating coils around the areas to be welded of the steel and aluminum rods; using the induced current generated by the high-frequency electromagnetic induction heating coils to heat the steel claw to a preset temperature, controlling the heating time to a preset time, and utilizing the skin effect and proximity effect to achieve melting on the aluminum side and solid bonding on the steel side, forming a multi-faceted stable joint.

[0007] In this embodiment, the differences between aluminum and steel, such as their large differences in melting points and thermal expansion coefficients, are difficult to overcome by traditional welding methods. High-frequency induction brazing, however, utilizes the characteristics of precise heating and localized heating to effectively avoid the formation of brittle intermetallic compounds by connecting the molten aluminum side to the solid steel side. Traditional welding methods, such as fusion welding and low-temperature brazing, suffer from long heating times and relatively low joint strength in practical applications. High-frequency induction brazing, on the other hand, can achieve precise heating in a shorter time and form a stable weld joint. This significantly improves work efficiency. Through a reasonable welding process, especially the application of high-frequency induction heating at the aluminum-steel joint, the resistivity of the aluminum-steel joint can be effectively reduced, and the conductivity of the anode structure of the electrolytic cell can be increased, thereby improving overall electrolysis efficiency and equipment stability. Compared with traditional welding equipment, high-frequency induction heating devices have higher thermal efficiency and lower energy consumption, increasing production efficiency while reducing energy consumption. This helps to reduce overall equipment investment costs. High-frequency induction heating technology can precisely control the heating area and temperature, avoiding the overheating or uneven heating problems commonly found in traditional welding. This results in more stable weld joint quality, meeting the requirements of demanding engineering applications. By precisely controlling the heating process and selecting appropriate brazing filler metal, the mechanical properties of the joint can be effectively improved, especially the durability and strength of the connection area. Compared with traditional welding methods, welded joints have higher reliability and a longer service life.

[0008] As one possible implementation, the method further includes: the aluminum-based brazing filler metal comprising, by weight percentage: Al 80-85%, Cu 5-10%, Mg 1-3%, Si 3-6%, La 1%, and Ce 1%.

[0009] As one feasible implementation, the deoxidation includes: using 400-grit coarse sandpaper to polish the areas of the steel and aluminum rods to be welded to remove the surface oxide layer and scratches, polishing until the surface to be welded reveals a silvery-white metallic luster, and then further smoothing and flattening the surfaces of the steel plate and aluminum rods to be welded.

[0010] As one feasible implementation, the method further includes: weighing Al 80-85%, Cu 5-10%, Mg 1-3%, Si 3-6%, La 1%, and Ce 1% by weight, stirring evenly, and then melting the molten metal to obtain aluminum-based brazing filler metal for welding.

[0011] As one feasible implementation, the stirring time of the aluminum-based brazing filler metal is not less than 120s; the melting temperature is 700-800℃, the melting time is 60-120s, and the cooling method is room temperature molding.

[0012] As one feasible implementation, the number of screws is 4, the length is 2cm, and the 4 screws are evenly fixed in a ring array to the end of the steel rod to be welded, and are located in the hollow structure of the connector.

[0013] As one feasible implementation, the aluminum rod has a diameter of 5cm and a length of 5cm, the steel rod has a diameter of 5cm and a length of 5cm, and the connecting piece on one side of the steel rod has a length of 2cm.

[0014] As one feasible implementation, the preset temperature is 700°C and the preset time is 300 seconds.

[0015] As a feasible implementation method, the high-frequency electromagnetic induction heating coil is a hollow tube made of copper with a diameter of 8cm.

[0016] Secondly, this application also provides a high-frequency induction brazing device for aluminum-steel dissimilar metals in an electrolytic cell anode structure, comprising: a connector disposed on the surface of the steel rod to be welded, the connector being a hollow annular structure capable of accommodating the insertion of the end of the aluminum rod to be welded; multiple screws disposed in a circular array uniformly fixed to the end of the steel rod to be welded, and located within the hollow structure of the connector; and a high-frequency electromagnetic induction heating coil disposed on the periphery of the area to be welded on the steel rod and aluminum rod, for heating the steel rod and aluminum rod, wherein an aluminum-based brazing filler layer is disposed between the end of the steel rod and aluminum rod to be welded, the interior of the connector, and the periphery of the aluminum rod.

[0017] In this embodiment, the tight fixing design of the connectors and screws effectively prevents relative displacement between the aluminum and steel rods during welding, thus ensuring the stability and accuracy of the welded joint. The hollow annular connector design provides an accurate positioning space for the aluminum-steel joint, contributing to improved welding quality. High-frequency electromagnetic induction heating technology offers higher heating efficiency and precision compared to traditional welding methods. The induction heating coil can heat the surface of the steel claw to a preset temperature in a short time, and generate localized heat accumulation during welding through the skin effect and proximity effect, thereby ensuring uniform heat distribution during welding. High-frequency induction brazing can effectively control the temperature distribution in the welding area, avoiding the problem of brittle Fe-Al intermetallic compounds easily forming at the aluminum-steel interface during fusion welding. This significantly improves the strength and toughness of the aluminum-steel joint, reducing the risk of cracking and brittleness. The aluminum-based brazing filler metal melts rapidly during heating and fills the gaps in the joint area, enhancing the electrical conductivity and mechanical strength of the aluminum-steel joint. Compared with traditional low-temperature brazing, the aluminum-based brazing filler metal provides better wettability and connection, reducing weak points at the joint. Compared to traditional welding equipment, this high-frequency induction heating method can complete the heating and joining process much faster, thus significantly improving production efficiency. The high-frequency induction heating device has high energy efficiency, effectively saving energy and equipment investment costs. By precisely controlling the heating process and welding parameters, the strength and stability of the aluminum-steel joint can be guaranteed. This allows the welding method to meet the high requirements for joint strength and conductivity in the anode structure of electrolytic cells, improving the long-term service life and stability of the equipment. In summary, this high-frequency induction brazing device overcomes the difficulties in joining dissimilar metals like aluminum and steel through precise control of the welding process and optimization of the joint structure, exhibiting significant advantages and achieving efficient, stable, and low-cost welding results.

[0018] As one feasible implementation, the number of screws is 4, the length is 2cm, and the 4 screws are evenly fixed in a ring array to the end of the steel rod to be welded, and are located in the hollow structure of the connector.

[0019] As one feasible implementation, the aluminum rod has a diameter of 5cm and a length of 5cm, the steel rod has a diameter of 5cm and a length of 5cm, and the connecting piece on one side of the steel rod has a length of 2cm.

[0020] As one feasible implementation, the high-frequency electromagnetic induction heating coil is a hollow tube made of copper.

[0021] As one feasible implementation, the high-frequency electromagnetic induction heating coil has a diameter of 8 cm.

[0022] As one feasible implementation, the high-frequency electromagnetic induction heating coil is processed to have an shape consistent with the welding area of ​​the aluminum rod and the steel rod, and the high-frequency electromagnetic induction heating coil is 20mm away from the outer peripheral surface of the steel rod.

[0023] As one possible implementation, the high-frequency electromagnetic induction heating coil includes an arc-shaped induction coil and a square induction coil.

[0024] As one feasible implementation, the induction power of the high-frequency electromagnetic induction heating coil is 0-40kW.

[0025] As one feasible implementation, the induced current of the high-frequency electromagnetic induction heating coil is 70-90A.

[0026] As one feasible implementation, the induction heating time of the high-frequency electromagnetic induction heating coil is 90-300s.

[0027] As one feasible implementation, the distance between the surfaces of the aluminum rod and the steel rod to be welded is 80-120 mm.

[0028] In summary, this application has the following beneficial effects:

[0029] First, the aluminum-based brazing filler metal prepared in this invention uses Al, Cu, Mg, Si metallic elements and Ce and La rare elements. Cu improves conductivity and increases the connection strength of the weld joint; Mg reduces the oxidation tendency of the filler metal and improves its wettability; Si and Al form a eutectic structure, significantly lowering the melting point of the filler metal, while Si also improves its ductility; and the rare elements Ce and La purify the molten pool, refine the grains, and improve wettability. The resulting filler metal exhibits excellent wettability and can inhibit the excessive growth of intermetallic compounds (IMCs) at the metallurgical interface, thereby improving the mechanical properties of the dissimilar metal weld joint between the aluminum anode guide rod and the steel claw, achieving efficient and reliable connection between the aluminum anode guide rod and the steel claw, and enabling wider application in the brazing industry.

[0030] Secondly, the high-frequency induction brazing method for dissimilar metals, including the anode aluminum guide rod and steel claw, provided by this invention achieves induction brazing of steel / steel and induction fusion welding of aluminum / steel in stages. This method is simple, convenient, low-cost, and easy to operate, overcoming the problems of complex processes, high costs, and difficulty in control associated with aluminum-steel fusion welding and pressure welding. Attached Figure Description

[0031] The accompanying drawings used in the description of the embodiments are briefly introduced below.

[0032] In the various figures, the same elements are represented by similar reference numerals. For clarity, the various parts in the figures are not drawn to scale, and certain features may be exaggerated or omitted to more clearly illustrate and explain this application.

[0033] Figure 1 A schematic flowchart of a high-frequency induction brazing method for aluminum-steel dissimilar metals in an electrolytic cell anode structure, provided in an embodiment of this application, is shown.

[0034] Figure 2 A schematic flowchart of a high-frequency induction brazing method for aluminum-steel dissimilar metals in an electrolytic cell anode structure, provided in an embodiment of this application, is shown.

[0035] Figure 3 A schematic diagram of the structure showing a screw fixed to the end of a steel bar to be welded is shown;

[0036] Figure 4 This paper presents a schematic diagram of the structure of a high-frequency induction brazing device for aluminum and steel dissimilar metals with an anode structure in an electrolytic cell, as provided in an embodiment of this application.

[0037] In the diagram, 1 is an aluminum rod; 2 is a high-frequency electromagnetic induction heating coil; 3 is a connector; and 4 is a steel rod. Detailed Implementation

[0038] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0039] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0041] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0042] In the description of this specification, the references to terms such as "some implementations," "some embodiments," "exemplary," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0043] The term "room temperature" as used in this specification has a meaning known in the art and generally refers to 24-28°C.

[0044] High-frequency induction fusion brazing (HFIFB), as a novel composite heat source joining technology, utilizes a high-frequency alternating magnetic field to generate eddy current heating in a localized area of ​​the joint, achieving precise temperature control to melt the aluminum side and solidify the steel side. It combines the high-strength bond of fusion welding with the low heat input advantage of brazing. Its core technology lies in utilizing the "skin effect" and "proximity effect" of high-frequency induction heating to selectively heat the filler metal. By adjusting welding parameters (frequency, power) and filler metal composition, the IMC layer thickness can be effectively controlled and the interfacial stress distribution improved, simultaneously achieving a high-efficiency, low-deformation connection.

[0045] This application provides a high-frequency induction brazing device for aluminum-steel dissimilar metals in an electrolytic cell anode structure. It achieves efficient bonding between aluminum and steel by utilizing the principle of high-frequency electromagnetic induction heating, overcoming a series of problems in traditional welding methods for joining dissimilar metals. The specific principle is as follows: High-performance bonding between aluminum and steel is achieved by optimizing the composition and structural process of the aluminum-based brazing filler metal. The aluminum-based brazing filler metal is composed of Al, Cu, Mg, Si, La, and Ce in a specific ratio. Cu and Si synergistically lower the melting point of the filler metal and improve wettability, while La and Ce refine the grains and enhance joint strength. During welding, the brazing filler metal and screws are placed on the steel side surface. Utilizing the skin effect and proximity effect of high-frequency induction heating, the melting of the aluminum side and the solid-state bonding of the steel side are precisely controlled, suppressing the excessive growth of brittle Fe-Al intermetallic compounds (IMCs). The mechanical anchoring effect of the screws achieves a stable multi-faceted connection. This method features low heat input, low deformation, and high joint strength. Besides being suitable for high-frequency induction brazing of aluminum-steel dissimilar metals in an electrolytic cell anode structure, it is also applicable to lightweight manufacturing of dissimilar metals in the automotive, aerospace, and other fields.

[0046] The preferred embodiments of the present invention will be described in further detail below.

[0047] Figure 1 This document illustrates a flowchart of a high-frequency induction brazing method for aluminum-steel dissimilar metals in an electrolytic cell anode structure, as provided in an embodiment of this application (the flowchart can be referenced simultaneously). Figure 2 ).like Figure 1 As shown, the method includes the following steps:

[0048] S101. A hollow annular connector is provided at the end of the steel bar to be welded, the connector being able to accommodate the insertion of the end of the aluminum bar to be welded.

[0049] In this step, the design of the annular connector involves placing a hollow annular connector at the end of the steel bar to be welded. The purpose of this connector is to provide a stable insertion space for the end of the aluminum bar to be welded. This connector design helps maintain precise positioning between the aluminum and steel bars and ensures the stability of the connection area.

[0050] Optionally, a Q235 steel bar with a diameter of 5cm and a length of 5cm can be used for welding, and an aluminum bar with a diameter of 5cm and a length of 5cm can be used for welding.

[0051] S102. Deoxidize and sandblast the areas to be welded on the steel and aluminum bars and the connecting parts.

[0052] In this step, prior to welding, the areas of the steel and aluminum bars to be welded, as well as the connectors, undergo deoxidation and sandblasting to remove the oxide layer and impurities from the surface. This process helps improve the weldability of the metal surface and reduces the impact of oxides and other contaminants on the joint quality.

[0053] In some embodiments, deoxidation includes: using 400-grit coarse sandpaper to polish the areas of the steel and aluminum bars to be welded to remove the surface oxide layer and scratches. After polishing until the surface to be welded shows a silvery-white metallic luster, the surfaces of the steel plate and aluminum bars to be welded are further smoothed and flattened. For example, an ultrasonic cleaner is used to clean the surfaces of the steel plate and aluminum bars to be welded to achieve smoothing and flattening. Afterward, sandblasting is performed on the deoxidized steel side and aluminum side.

[0054] Optionally, sandblasting specifically includes: at room temperature of 25°C, using sand particles made of at least one of silicon carbide, brown corundum, and garnet, with a spray gun pressure ≥0.3MPa and a spray gun distance ≤300mm from the material surface, thereby uniformly removing the oxide layer from the surface of the steel and aluminum rods to be welded.

[0055] S103. After fixing multiple screws to the end of the steel rod to be welded after processing, place aluminum-based brazing filler metal inside the connector, wherein the aluminum-based brazing filler metal includes Al, Cu, Mg, Si, La and Ce metal elements.

[0056] In this step, an aluminum-based brazing filler metal is placed in the joint area to be welded. The aluminum-based filler metal has a low melting point and can effectively fill the aluminum-steel joint area. The selection and configuration of the aluminum-based filler metal are crucial to this technology, ensuring good welding results and joint strength. In some embodiments, the weight percentages of each element in the Al-based filler metal are Al 80-85%, Cu 5-10%, Mg 1-3%, Si 3-6%, La 1%, and Ce 1%. It should be noted that the raw materials for Cu, Mg, Si, and Al are metal particles with a purity of 99.9%. Cu and Si synergistically lower the melting point of the filler metal and improve wettability, while La and Ce refine the grains and enhance joint strength.

[0057] Alternatively, four 2cm long screws can be used, arranged in a ring, to fix the steel to the treated surface. (See here for more information.) Figure 3 , Figure 3 A schematic diagram of the structure showing a screw fixed to the end of a steel bar to be welded is shown.

[0058] S104. After inserting the end of the aluminum rod to be welded into the connector, arrange high-frequency electromagnetic induction heating coils around the areas of the steel rod and aluminum rod to be welded.

[0059] In this step, for example, the treated Q235 steel bar and aluminum bar are placed inside the high-frequency electromagnetic induction heating coil with the aluminum bar on top and the Q235 steel bar on the bottom. The treated surface of the aluminum bar, the hollow structure (connector) of the Q235 steel bar, the screws, and the aluminum-based brazing filler metal are positioned within the coil, and their positions are adjusted to avoid contact with the high-frequency electromagnetic induction heating coil. For example, the distance between the high-frequency electromagnetic induction heating coil and the outer circumference of the steel bar is set to 20mm to prevent mutual contact. After completing the above steps, check whether the equipment functions normally and set the welding parameters. See here for more information. Figure 4 , Figure 4 This paper presents a schematic diagram of the structure of a high-frequency induction brazing device for aluminum and steel dissimilar metals with an anode structure in an electrolytic cell, as provided in an embodiment of this application.

[0060] S105. The steel claw is heated to a preset temperature by the induced current generated by the high-frequency electromagnetic induction heating coil. The heating time is controlled to a preset time. By utilizing the skin effect and proximity effect, the aluminum side melts and the steel side solidifies to form a multi-faceted stable joint.

[0061] In this step, the current generated by the high-frequency electromagnetic induction heating coil rapidly heats the surface of the steel rod to a preset temperature through the skin effect and proximity effect, while the aluminum rod remains at a relatively lower temperature. This process controls the heat distribution, avoiding welding defects caused by uneven heat distribution in traditional welding. Melting and solid-state bonding: Under the action of high-frequency electromagnetic induction heating, the end of the aluminum rod to be welded melts, while the steel claw remains solid. By precisely controlling the heating time and temperature, a stable joint is formed between the aluminum and steel at the microstructure level. This bonding method not only avoids the problem of easily forming brittle Fe-Al intermetallic compounds in traditional welding but also effectively improves the structural strength and durability of the joint.

[0062] Optionally, the preset temperature is 700℃, and the preset time is 300s. The high-frequency electromagnetic induction heating coil is a hollow copper tube with a diameter of 8cm. Optionally, the high-frequency electromagnetic induction heating coil model is LH-40KW.

[0063] Figure 4 This illustration shows a structural schematic diagram of a high-frequency induction brazing device for aluminum-steel dissimilar metals with an anode structure in an electrolytic cell, provided in an embodiment of this application. (See also...) Figure 4 This application also provides a high-frequency induction brazing device for dissimilar metals, aluminum and steel, with an anode structure in an electrolytic cell, applied to the above-mentioned brazing method. The high-frequency induction brazing device mainly includes: a connector 3, disposed on the surface of the steel rod 4 to be welded; the connector 3 is a hollow annular structure, and the connector 3 can accommodate the insertion of the end of the aluminum rod 1 to be welded; screws ( Figure 4 Not shown, please refer to Figure 3Multiple heating coils, arranged in a circular array, are uniformly fixed to the ends of the steel rod 4 to be welded and located within the hollow structure of the connector 3. A high-frequency electromagnetic induction heating coil 2 is disposed around the welding area of ​​the steel rod 4 and aluminum rod 1, used to heat the steel rod 4 and aluminum rod 1. An aluminum-based brazing filler layer (not shown in the figure) is provided between the welding ends of the steel rod 4 and aluminum rod 1, the interior of the connector 3, and the periphery of the aluminum rod 1. In one embodiment, the spacing between the welding surfaces of the aluminum rod and the steel rod is 80-120 mm to facilitate the filling of the aluminum-based brazing filler.

[0064] The connector 3, with its hollow annular structure, is positioned at the welding end of the steel rod 4. Its primary function is to provide a precise insertion space for the welding end of the aluminum rod 1. The hollow annular design stably fixes the positions of the aluminum rod 1 and the steel rod 4, ensuring their proper connection during welding. The structural design of connector 3 enhances the sealing and stability during the welding process.

[0065] Screw fixing: Multiple screws are evenly distributed at the end of the steel rod 4 to be welded, located within the hollow structure of the connector 3. The function of these screws is to ensure a tight fit between the connector 3 and the steel rod 4, preventing relative displacement during welding. Simultaneously, the screws also help stabilize the connection area, preventing welding defects caused by temperature fluctuations or other external forces.

[0066] High-frequency electromagnetic induction heating coil 2: The high-frequency electromagnetic induction heating coil 2 is arranged around the welding areas of the steel rod 4 and aluminum rod 1. The main function of this heating coil is to generate an electromagnetic induction effect through the action of high-frequency current, rapidly heating the welding areas of the steel rod 4 and aluminum rod 1. By precisely controlling the frequency and power of the induced current, the surface of the steel rod 4 can be rapidly heated to the preset temperature, while the aluminum rod 1 is maintained at a suitable melting temperature. The precise control of high-frequency induction heating avoids the problems of uneven heat distribution and overheating in traditional heating methods.

[0067] Aluminum-based brazing filler layer: An aluminum-based brazing filler layer is provided between the steel rod 4 and the aluminum rod 1, inside the connector 3, and around the aluminum rod 1. The aluminum-based brazing filler has a low melting point, allowing it to melt rapidly during heating and fill the gaps between the aluminum and steel joints. Through the melting action of the aluminum-based brazing filler, a strong metallic connection is formed between the aluminum rod 4 and the steel rod 4, thereby enhancing the strength and conductivity of the joint.

[0068] Optionally, the aluminum rod 1 has a diameter of 5cm and a length of 5cm, the steel rod 4 has a diameter of 5cm and a length of 5cm, and the connector 3 on one side of the steel rod 4 has a length of 2cm. Optionally, the connector 3 can be made of the same material as the steel rod and welded to the end of the steel rod 4 to be welded. Alternatively, the connector 3 can be constructed by machining a cylindrical groove at the end of the steel rod 4 to be welded; this application does not impose strict limitations on this.

[0069] In some embodiments, the high-frequency electromagnetic induction heating coil 2 is a hollow copper tube with a diameter of 8cm. Specifically, after processing, the shape of the high-frequency electromagnetic induction heating coil 2 matches the welding area of ​​the steel rod 4 and the aluminum rod 1. In one specific embodiment, the distance between the high-frequency electromagnetic induction heating coil 2 and the surface of the steel rod 4 is 20mm. Optionally, the high-frequency electromagnetic induction heating coil 2 includes an arc-shaped induction coil and a square induction coil. The induction power of the high-frequency electromagnetic induction heating coil 2 is 0-40kW, the induction current is 70-90A, and the induction heating time is 90-300s. Optionally, the high-frequency electromagnetic induction heating coil is model LH-40KW.

[0070] Melting and bonding during welding: Under the action of high-frequency electromagnetic induction heating, the end of aluminum rod 1 to be welded melts, while steel rod 4 remains solid. The melting of aluminum-based brazing fills the gaps in the aluminum-steel joint. By precisely controlling the heating time (300s) and temperature (700℃), aluminum rod 1 and steel rod 4 ultimately form a stable joint in the microstructure. Through solid bonding and bonding with molten aluminum, the mechanical properties and durability of the joint are ensured.

[0071] To further illustrate this application, the technical solutions provided by this application are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of this application.

[0072] Example 1

[0073] A high-frequency induction brazing method for aluminum / steel dissimilar metals in the anode structure of an electrolytic cell, comprising the following steps:

[0074] (1) Weigh and mix six metals, Cu, Mg, Si, Al, La and Ce, in proportions of 10g, 3g, 4g, 32g, 0.5g and 0.5g respectively.

[0075] (2) Pour the metals Cu, Mg, Si, Al, La and Ce into a crucible and heat them at a temperature of 720°C for 90 seconds until the metals are completely melted. Continue stirring for 150 seconds.

[0076] (3) After heating, pour the metal in the crucible into the mold and cool it at room temperature to form the shape.

[0077] (4) Select an aluminum rod with a diameter of 5cm and a length of 5cm, and a steel rod with a diameter of 5cm and a length of 5cm. The steel rod has a hollow ring structure protruding 2cm on one side. Use 400-grit coarse sandpaper to polish the Q235 steel rod and aluminum rod to remove the surface oxide layer and scratches. After polishing until the cross-section reveals a silvery-white metallic luster, further smooth and flatten the two cross-sections. After the treatment is completed, the surface is sandblasted.

[0078] (5) After the pretreatment is completed, four 2cm long screws are fixed in a ring shape on the treated surface of the Q235 steel rod.

[0079] (6) The prepared block aluminum-based brazing filler metal is evenly placed inside the hollow structure of the Q235 steel rod.

[0080] (7) Place the treated Q235 steel rod and aluminum rod in the copper coil in the order of aluminum rod on top and Q235 steel rod on the bottom, so that the treated surface of the aluminum rod, the hollow structure of the Q235 steel rod, the screw and the aluminum-based brazing filler are placed in the coil, and adjust the position to avoid contact with the copper coil.

[0081] (8) Check all functions of the high-frequency induction heating equipment and adjust the welding parameters. The specific welding parameters are: heating temperature of 700° and heating time of 300s.

[0082] (9) When the heating time reaches 300s, turn off the high-frequency induction heating equipment.

[0083] Example 2

[0084] A high-frequency induction brazing method for aluminum / steel dissimilar metals in the anode structure of an electrolytic cell, comprising the following steps:

[0085] (1) Weigh and mix six metals, Cu, Mg, Si, Al, La and Ce, in proportions of 10g, 4g, 6g, 29g, 0.5g and 0.5g respectively.

[0086] (2) Pour the metals Cu, Mg, Si, Al, La and Ce into a crucible and heat them at 800 degrees for 100 seconds until the metals are completely melted. Continue stirring for 130 seconds.

[0087] (3) After heating, pour the metal in the crucible into the mold and cool it at room temperature to form the shape.

[0088] (4) Select an aluminum rod with a diameter of 5cm and a length of 5cm, and a steel rod with a diameter of 5cm and a length of 5cm. The steel rod has a hollow ring structure protruding 2cm on one side. Use 400-grit coarse sandpaper to polish the Q235 steel rod and aluminum rod to remove the surface oxide layer and scratches. After polishing until the cross-section reveals a silvery-white metallic luster, further smooth and flatten the two cross-sections. After the treatment is completed, the surface is sandblasted.

[0089] (5) After the pretreatment is completed, four 2cm long screws are fixed in a ring on the treated surface of the Q235 steel rod.

[0090] (6) Place the prepared aluminum-based brazing filler metal evenly inside the hollow structure of the Q235 steel rod.

[0091] (7) Place the treated Q235 steel rod and aluminum rod in the copper coil in the order of aluminum rod on top and Q235 steel rod on the bottom, so that the treated surface of the aluminum rod, the hollow structure of the Q235 steel rod, the screw and the aluminum-based brazing filler are placed in the coil, and adjust the position to avoid contact with the copper coil.

[0092] (8) Check all functions of the high-frequency induction heating equipment and adjust the welding parameters. The specific welding parameters are: heating temperature of 700° and heating time of 300s.

[0093] (9) When the heating time reaches 300s, turn off the high-frequency induction heating equipment.

[0094] The high-frequency induction brazing device for aluminum-steel dissimilar metals in the anode structure of the electrolytic cell provided in this application embodiment, by setting a hollow tube structure and a steel-side fixing screw at one end of a Q235 steel rod, places the aluminum rod, Q235 steel rod, aluminum-based brazing filler metal, and screw inside a coil, and generates eddy current heating effect in a local area through a high-frequency alternating magnetic field, utilizing the "skin effect" and "proximity effect" of high-frequency induction heating for local heating, thereby achieving multi-faceted and stable connections between the aluminum-based brazing filler metal and the aluminum rod, the aluminum-based brazing filler metal and the Q235 steel, the aluminum-based brazing filler metal and the inner wall of the hollow tube structure, and the aluminum-based brazing filler metal and the screw; combined with the low heat input advantage of brazing, the aluminum-based brazing filler metal and the screw finally form a mechanical-metallurgical composite connection interface, achieving a high-efficiency, low-deformation connection, and obtaining a welded joint with no obvious defects and excellent mechanical properties. Meanwhile, the addition of Mg to the brazing filler metal lowers its melting point, while Cu significantly improves its wettability and flowability, making it easier to spread on the base metal surface. Si significantly lowers the melting point, enabling brazing at lower temperatures. La effectively increases the tensile strength and spreading area, while Ce significantly improves its spreadability and shear strength. In summary, the addition of Mg, Cu, Si, La, and Ce can optimize the performance of aluminum-based brazing filler metals in terms of melting point, wettability, flowability, and mechanical properties, thereby improving the quality and reliability of brazed joints.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application. Those skilled in the art should understand that although this application has been described in detail with reference to the foregoing embodiments, modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to depart from the spirit and scope of the technical solutions in the embodiments of this application.

Claims

1. A high-frequency induction brazing device for aluminum-steel dissimilar metals in an electrolytic cell anode structure, characterized in that, include: A connector is provided on the surface of the steel rod to be welded. The connector is a hollow annular structure and can accommodate the insertion of the end of the aluminum rod to be welded. Multiple screws are arranged in a circular array and evenly fixed to the end of the steel rod to be welded, and are located inside the hollow structure of the connector. A high-frequency electromagnetic induction heating coil is disposed on the periphery of the area to be welded on the steel bar and aluminum bar, and is used to heat the steel bar and aluminum bar. An aluminum-based brazing filler layer is disposed between the end of the steel bar and aluminum bar to be welded, the inside of the connector and the periphery of the aluminum bar.

2. The apparatus according to claim 1, characterized in that, The number of screws is 4, and the length is 2cm. The 4 screws are evenly fixed in a ring array at the end of the steel rod to be welded, and are located in the hollow structure of the connector.

3. The apparatus according to claim 1, characterized in that, The aluminum rod has a diameter of 5cm and a length of 5cm, the steel rod has a diameter of 5cm and a length of 5cm, and the connector on one side of the steel rod has a length of 2cm.

4. The apparatus according to claim 1, characterized in that, The high-frequency electromagnetic induction heating coil is a hollow tube made of copper.

5. The apparatus according to claim 1, characterized in that, The diameter of the high-frequency electromagnetic induction heating coil is 8cm.

6. The apparatus according to claim 1, characterized in that, The high-frequency electromagnetic induction heating coil is processed to match the welding area of ​​the aluminum rod and steel rod, and the high-frequency electromagnetic induction heating coil is 20mm away from the outer circumferential surface of the steel rod.

7. The apparatus according to claim 1, characterized in that, The high-frequency electromagnetic induction heating coil includes an arc-shaped induction coil and a square induction coil.

8. The apparatus according to claim 1, characterized in that, The induction power of the high-frequency electromagnetic induction heating coil is 0-40kW.

9. The apparatus according to claim 1, characterized in that, The induced current of the high-frequency electromagnetic induction heating coil is 70-90A.

10. The apparatus according to claim 1, characterized in that, The induction heating time of the high-frequency electromagnetic induction heating coil is 90-300s.

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