Device for adding magnesium into Al-Mg-Si alloy with high magnesium content

Abstract

The utility model relates to the technical field of aluminum alloy manufacturing equipment, in particular to a high-magnesium-content Al-Mg-Si alloy magnesium adding device which comprises an outer cylinder arranged in an open mode. One end of the T-shaped ventilation device is located at one end of an opening of the outer barrel, the conical cover plate is welded to the outer circumference of a ventilation outlet, extending into the outer barrel, of the other end of the T-shaped ventilation device, the molten aluminum barrel is defined by the inner wall of the outer barrel and the conical cover plate, and the vacant magnesium barrel is located below the molten aluminum barrel. The frame vacant magnesium cylinder is connected with a bearing arm in a welding manner; a pressing device is connected to the outer portion of the T-shaped ventilation device in a welded mode and provided with a handle, the large opening end of the conical cover plate is welded to a supporting ring, and the large opening end of the conical cover plate is movably clamped in the outer cylinder through the supporting ring. According to the method, the utilization rate of magnesium is increased through isolation design and accurate control in the vacuum environment, meanwhile, the purity of molten aluminum is guaranteed, and an effective technical means is provided for manufacturing the Al-Mg-Si alloy with the high magnesium content.

Description

Technical Field

[0001] This application relates to the technical field of aluminum alloys, and particularly relates to a device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content. Background Art

[0002] In the past two decades, the global energy problem has become increasingly serious, which makes reducing the weight of automobiles and lowering fuel consumption the key for major automobile manufacturers to improve their competitiveness. Therefore, in order to reduce fuel consumption and also to reduce the pollution of the atmospheric environment caused by automobile exhaust emissions, reducing the weight of automobiles is an important measure. The rise of new energy vehicles has solved the pollution problem caused by fuel exhaust, but aluminum alloys, with their high specific strength, excellent corrosion resistance and other advantages, have gradually replaced cast iron with a larger density and have been widely used in the fields of automobiles, aviation, etc. Among aluminum alloys, Al-Si series cast aluminum alloys have good casting performance and corrosion resistance, and thus have become the most widely used cast aluminum alloys. As one of the lightest metal elements, the density of Mg is much lower than that of Al. Adding Mg to Al-Si alloys can not only reduce their density and increase the specific strength, but also the Mg2Si formed by the combination of Mg and Si can effectively strengthen the Al matrix and improve the mechanical properties of the alloy. However, in traditional Al-Si-Mg alloys, Mg2Si, as the second phase, strengthens the Al matrix by precipitation during solution-aging heat treatment. As the contents of Mg and Si increase, the size of the precipitated Mg2Si during aging is larger than that of the GP zone, and its strengthening effect will weaken. Once large-sized irregularly shaped particles are formed, the mechanical properties of the alloy will drop severely. Therefore, the addition amount of Mg in these alloys is only about 0.35%.

[0003] In recent years, Al-Mg2Si alloys formed by directly precipitating the Mg2Si phase from molten aluminum have received extensive attention from scholars at home and abroad. Since this alloy contains a higher amount of Mg than traditional Al-Si-Mg alloys, up to more than 10%, it has excellent properties such as higher specific stiffness, specific strength and wear resistance, and has a broader application prospect as a new lightweight material in the fields of aerospace, automobiles, etc.

[0004] Although the density of magnesium is low, its binding force with oxygen is very strong. In the air, especially in the state of high-temperature molten aluminum, it is extremely easy to oxidize and burn out, and the burning loss rate can be as high as 30%. This not only causes waste of magnesium, increases production costs, but also pollutes the air. At the same time, the oxidation and burning loss of magnesium produce a large amount of oxidized industrial waste residues, polluting the environment. A small amount entering the molten aluminum forms oxide inclusions in the alloy, which greatly reduces the mechanical properties of the alloy. Especially for Al-Mg2Si alloys with a Mg content of up to more than 10%, these problems are more serious.

[0005] Currently, for traditional aluminum-silicon-magnesium alloys with a low magnesium content (<1.0%), the method of adding magnesium is to press a pure magnesium block wrapped in aluminum foil into the molten aluminum using a ladle after the aluminum is melted, or to add it in the form of an Al-Mg master alloy, and a solvent is used to protect the surface of the aluminum liquid. Since it is added under the atmosphere, magnesium is not well isolated from oxygen in the air, and using this method for aluminum-magnesium alloys and aluminum-magnesium-silicon alloys with a high magnesium content will cause a large amount of magnesium loss.

[0006] The patent "High-strength Al-Mg-Sr alloy ingot and its preparation method" with application number CN202210335307.1 contains 4.0 - 4.9% magnesium, 0.1 - 0.5% strontium, 0.4 - 1.0% manganese, 0.05 - 0.25% chromium, and the balance is aluminum. After melting the aluminum ingot in an ordinary resistance furnace, aluminum-manganese and aluminum-chromium master alloys, pure magnesium blocks, and aluminum-strontium master alloys are added in sequence. After complete melting, it is placed in a negative pressure environment and refined by introducing high-purity argon gas to obtain a refined melt, eliminating casting defects such as inclusion pores generated by the oxidation of magnesium elements. Since the addition of pure magnesium blocks and aluminum-strontium master alloys is not carried out under negative pressure and argon protection, it causes a relatively large amount of magnesium loss, pollutes the environment, generates a large amount of oxidation slag, and the magnesium content is uncontrollable, affecting the composition of the final alloy.

[0007] The patent "A preparation method of a high-performance cast Al-Mg-Li alloy" with application number CN202311303254.6 contains 5.0% magnesium, 2.5% lithium, 1.25% zinc, 0.63% copper, 0.63% zirconium, and the balance is aluminum. A vacuum induction melting furnace equipped with feeding, stirring, and an argon blowing device at the bottom is used to melt / process the aluminum liquid. After melting raw materials such as aluminum ingots, pre-treated pure magnesium blocks wrapped in aluminum foil and lithium particles are successively added to the melting crucible using the vacuum feeding device of the vacuum induction melting furnace, and the electromagnetic and mechanical stirring devices are turned on for stirring. Then, the melt in the crucible is poured into the cavity of a metal mold under a vacuum environment. This process places raw materials such as pure magnesium and lithium in a closed vacuum melting furnace and introduces an inert gas - argon for protection, effectively avoiding the oxidation loss and oxidation inclusions of magnesium and strontium elements. At the same time, electromagnetic and mechanical stirring makes the composition and structure more uniform, thus improving the performance and quality of the obtained alloy castings or ingots. However, this process uses a complex vacuum induction melting furnace equipped with feeding / blowing, stirring and other devices, with a large investment in equipment costs and cumbersome operation, which is not conducive to large-scale industrial production.

[0008] The patent "A Zinc-Aluminum-Magnesium Alloy Casting Device and Method" with the application number CN202110885884.3. In order to prevent the oxidation of magnesium elements during the casting process, sulfur is evenly sprinkled into the inner cavity of the ingot mold before casting. During casting, sulfur undergoes a chemical reaction with oxygen, consuming the residual oxygen in the inner cavity of the ingot mold, and the generated sulfur dioxide isolates oxygen. This method uses a simple device, which reduces the oxidation and burning loss of magnesium to a certain extent. However, this isolation of oxygen is not thorough and cannot completely achieve the purpose of isolating air to prevent magnesium oxidation. Utility Model Content

[0009] In view of the deficiencies of the above-mentioned existing technologies, the present utility model provides a device for adding magnesium to a high-magnesium-content Al-Mg-Si alloy. Through means such as a vacuum environment, isolation design, and precise control, this device realizes the isolation of oxygen, prevents oxidation, and greatly promotes the complete reaction of magnesium blocks and the purity of aluminum liquid.

[0010] The technical solutions provided in this application are as follows:

[0011] A device for adding magnesium to a high-magnesium-content Al-Mg-Si alloy, characterized in that it includes an open outer cylinder, a T-shaped ventilation device with one end located above the opening of the outer cylinder, a conical cover plate welded to the outer circumference of the ventilation outlet where the other end of the T-shaped ventilation device extends into the outer cylinder, an aluminum liquid cylinder formed by the inner wall of the outer cylinder and the conical cover plate, and an overhead magnesium cylinder located at the bottom inside the outer cylinder. The bottom end of the overhead magnesium cylinder is welded and connected to a bearing arm;

[0012] The outside of the T-shaped ventilation device is welded and connected with a pressing device, and the pressing device is provided with a handle. The large end of the conical cover plate is welded to a support ring, and the large end is movably clamped inside the outer cylinder through the support ring. The inner diameter of the outer cylinder is smaller than the outer diameter of the large end of the conical cover plate near the lower part of the large end of the conical cover plate.

[0013] Further, the top of the T-shaped ventilation device is provided with a ventilation pipe, which is connected to a vacuum pump through a left valve on the left side and to an argon gas cylinder through a right valve on the right side, and a filter screen is provided at the bottom of the other end.

[0014] The top of the overhead magnesium cylinder is provided with a baffle, which is welded to the cylinder body. The cylinder body is provided with air holes and a feeding door around it, and the bottom plate is provided with air holes and is welded to the bearing arm;

[0015] In an implementation scheme, in order to facilitate the discharge of gas, since the magnesium blocks are light, they can also effectively prevent the magnesium blocks from floating upward under the impact of aluminum liquid. Air holes are provided above the baffle.

[0016] Further, the bearing arm is connected to the bottom of the overhead magnesium cylinder in a communicating manner. Adopting a welded and hollow design facilitates the infiltration of aluminum liquid from all around.

[0017] Furthermore, the overhead magnesium cylinder is located at 1 / 3 to 1 / 2 of the height of the entire device.

[0018] The high-magnesium-content Al-Mg-Si alloy melting device of the present invention has remarkable beneficial effects:

[0019] For the external environment, the device can effectively prevent the occurrence of industrial waste residues such as oxidation slag. At the same time, it can also effectively reduce the emission of waste gas, protecting the environment to a large extent; for the alloy itself, it can greatly reduce casting defects such as oxidation inclusions, accurately control the content of magnesium in the alloy, and thus ensure the mechanical properties of the alloy; in terms of reducing the loss of magnesium blocks, the design of the conical cover plate and the support ring enables the aluminum liquid to uniformly and slowly penetrate into the magnesium blocks, reducing the direct loss and waste of magnesium blocks and improving the utilization rate of raw materials; in terms of precisely controlling the composition, through the precise control of the pressing device and the conical cover plate, the device can accurately control the inflow amount of aluminum liquid, thereby ensuring the accuracy and stability of the alloy composition.

[0020] In summary, the present invention realizes that in a vacuum environment, through isolation design and precise control, the magnesium blocks fully react with the aluminum liquid, improving the utilization rate of magnesium, while ensuring the purity of the aluminum liquid, providing an effective technical means for manufacturing high-magnesium-content Al-Mg-Si alloys.

[0021] The device first uses an inverted conical cover plate to divide the outer cylinder into two spaces. The formed aluminum liquid cylinder is used to pour aluminum liquid from the outside. Then, due to the change in the inner diameter of the cylinder and the action of the support ring, under the pressing of the pressing device, the lower support ring is in a tight fit with the inner wall of the outer cylinder, which helps to pump out the air and displace argon. When the pressing handle is released, due to the outer tension of the conical cover plate and the inner tension of the inner wall of the outer cylinder, the support ring will continuously move upward to a clearance fit relationship, and the aluminum liquid between the two will flow downward through the gap to the support arm, and the upper part of the support arm is provided with holes and overflows into the overhead magnesium cylinder. This process is carried out in an environment protected by argon, isolating the air and preventing oxidation. Therefore, through the above implementation methods, the process of adding magnesium to high-magnesium-content Al-Mg-Si alloys can be accurately controlled, improving the quality and performance of the alloy. At the same time, the device also has the advantages of simple structure, convenient operation, safety and reliability, etc., and is suitable for industrial production. Description of the Drawings

[0022] Figure 1 It is a schematic diagram of a device for adding magnesium to a high-magnesium-content Al-Mg-Si alloy as a whole in an embodiment of the present application.

[0023] Figure 2 It is a schematic diagram of a device for adding magnesium to a high-magnesium-content Al-Mg-Si alloy in an embodiment of the present application.

[0024] Figure 3 It is a schematic diagram of a device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content according to an embodiment of the present application.

[0025] Figure 4 It is a schematic diagram of a device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content according to an embodiment of the present application.

[0026] Explanation of reference numerals:

[0027] 1 - T-shaped ventilation device; 11 - ventilation pipe; 12 - filter screen; 13 - left valve; 14 - right valve;

[0028] 2 - conical cover plate; 21 - support ring;

[0029] 3 - empty overhead magnesium cylinder; 31 - baffle; 32 - feeding door; 33 - bottom plate; 34 - air holes;

[0030] 4 - bearing arm;

[0031] 5 - pressing device; 51 - handle. Detailed implementation manners

[0032] The present application will be further described in detail below with reference to all the drawings.

[0033] Embodiment 1

[0034] An embodiment of the present application discloses a device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content, including an outer cylinder 6 with an open mouth, a T-shaped ventilation device 1 at one end located outside the open mouth of the outer cylinder, a conical cover plate 2 welded to the outer circumference of the ventilation outlet at the other end of the T-shaped ventilation device extending into the outer cylinder, and an aluminum liquid cylinder 61 formed by the inner wall of the outer cylinder 6 and the conical cover plate 2. The aluminum liquid cylinder 61 is welded and connected to a bearing arm 4;

[0035] A pressing device 5 is welded and connected to the outside of the T-shaped ventilation device 1. The pressing device 5 is provided with a handle 51. The large-mouth end of the conical cover plate 2 is welded to a support ring 21. The large-mouth end of the conical cover plate 2 is movably clamped inside the outer cylinder 6 through the support ring 21. The inner diameter of the outer cylinder 6 is smaller than the outer diameter of the large-mouth end of the conical cover plate 2 near the lower part of the large-mouth end of the conical cover plate 2.

[0036] In this embodiment, a ventilation pipe 11 is provided at the top of the T-shaped ventilation device 1. The left side is connected to a vacuum pump through a left valve 13, the right side is connected to an argon gas cylinder through a right valve 14, and a filter screen 12 is provided at the bottom of the other end.

[0037] In this embodiment, a baffle 31 is provided at the top of the overhead magnesium cylinder 3, which is welded to the cylinder body of the overhead magnesium cylinder 3. Air holes and a feeding door 32 are provided around the cylinder body, and air holes are provided in the bottom plate 33 at the bottom. This facilitates the outward discharge of gas and prevents upward gas from blocking the infiltration of molten aluminum.

[0038] In one implementation, in order to facilitate the discharge of gas, since the magnesium blocks are light, they can also effectively block the upward floating of the magnesium blocks under the impact of molten aluminum, and air holes are provided above the baffle.

[0039] In this embodiment, the bearing arm 4 is connected to the bottom of the overhead magnesium cylinder 3 in a communicating manner. Welding connection and a hollow design are adopted to facilitate the infiltration of molten aluminum from all around.

[0040] In this embodiment, the overhead magnesium cylinder 3 is located at 1 / 3 of the height of the entire device.

[0041] The working process is as follows:

[0042] First, open the feeding door 32, place the pure magnesium blocks wrapped in aluminum foil on the overhead magnesium cylinder 3, close the feeding door 32, press the handle 51 to make the support ring (21) in close contact with the inner wall of the outer cylinder 6, and then pour enough molten aluminum required for the reaction, which has been melted, from the open end of the outer cylinder. Next, open the left valve (13) on the T-shaped ventilation device 1, start the vacuum pump, and evacuate the air inside the device to make the inside of the device reach a vacuum state. When a certain negative pressure is reached inside the device, close the left valve 13, open the right valve 14, and fill the device with argon to prevent the molten aluminum from undergoing an oxidation reaction with oxygen in the air during the reaction. After filling enough argon, close the right valve 14. At this time, the inside of the device is filled with argon, providing a good environment for the reaction between the molten aluminum and the magnesium blocks.

[0043] By gradually relaxing the handle 51 at the top, control the conical cover plate 2 to move upward in a small range, so that the molten aluminum gradually flows to the lower part of the device. The molten aluminum first flows through the hollow-designed bearing arm 4 to the lower part of the overhead magnesium cylinder 3, and then infiltrates through the bottom plate 33 to dissolve the magnesium blocks, forming an Al-Mg-Si alloy solution with a high magnesium content. During the reaction, the generated gas is discharged through the air holes in the baffle 31 and the cylinder body of the overhead magnesium cylinder 3. At the same time, since the inside of the device is filled with argon, it can effectively prevent the molten aluminum from undergoing an oxidation reaction with oxygen in the air.

[0044] The device first uses an inverted conical cover plate to divide the outer cylinder into two spaces. Molten aluminum is poured into the formed molten aluminum cylinder from the outside. Then, due to the change in the inner diameter of the cylinder and the effect of the support ring, under the pressing of the pressing device, the lower support ring is in a tight fit with the inner wall of the outer cylinder, which helps to pump out air and replace it with argon. When the pressing handle is released, due to the outer tension of the conical cover plate and the inner tension of the inner wall of the outer cylinder, the support ring will continuously move upward to a clearance fit relationship, and the molten aluminum between the two will flow downward through the gap to the support arm. There are openings in the upper part of the support arm, and the molten aluminum overflows into the overhead magnesium cylinder. This process is carried out in an environment protected by argon, isolating air and preventing oxidation. Therefore, through the above implementation method, it is possible to accurately control the process of adding magnesium to the Al-Mg-Si alloy with a high magnesium content, improving the quality and performance of the alloy. At the same time, the device also has the advantages of simple structure, convenient operation, safety and reliability, etc., and is suitable for industrial production.

[0045] The above are all preferred embodiments of this application, and do not limit the protection scope of this application accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. A device for adding magnesium to a high magnesium content Al-Mg-Si alloy, comprising: It comprises an outer cylinder with an open end, a T-shaped ventilator with one end located above the open end of the outer cylinder, a conical cover plate welded to the outer circumference of a ventilator outlet extending from the other end of the T-shaped ventilator to the inner wall of the outer cylinder, an aluminum liquid cylinder surrounded by the inner wall of the outer cylinder and the conical cover plate, and an overhead magnesium cylinder located at the inner bottom of the outer cylinder, wherein the bottom end of the overhead magnesium cylinder is welded to a bearing arm; The outside of the T-shaped ventilation device is welded and connected with a pressing device, which is provided with a handle. The large-mouth end of the conical cover plate is welded to a support ring, and the large-mouth end is movably clamped inside the outer cylinder through the support ring. The inner diameter of the outer cylinder is located below the large-mouth end of the conical cover plate and is smaller than the outer diameter of the large-mouth end of the conical cover plate.

2. A device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content according to claim 1, characterized in that: The top of the T-shaped ventilation device (1) is provided with a ventilation pipe (11), the left side of which is connected to a vacuum pump via a left valve (13), and the right side of which is connected to an argon gas bottle via a right valve (14), and a filter screen (12) is provided at the bottom of the other end.

3. The device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content according to claim 2, characterized in that: The top of the overhead magnesium cylinder (3) is provided with a baffle (31) which is welded to the cylinder body. The cylinder body is provided with air holes and a feeding door (32) around it. The bottom plate (33) is provided with air holes which is welded to the bearing arm (4).

4. The device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content according to claim 3, characterized in that: Air holes are provided above the baffle (31).

5. The device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content according to claim 4, characterized in that: The carrying arm (4) is connected to the bottom of the overhead magnesium cylinder (3).

6. The device for adding magnesium to an Al-Mg-Si alloy with a high magnesium content according to claim 5, characterized in that: The overhead magnesium cylinder is located at 1 / 3 to 1 / 2 of the height of the entire device.

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