Preparation equipment for low-density foamed aluminum

Abstract

According to the preparation equipment for the low-density foamed aluminum, a motor drives a stirring paddle to rotate in a containing space of a heating furnace, aluminum ingots and boron carbide can be fully mixed, it is ensured that boron carbide is evenly dispersed in molten aluminum, and a preparation basis is provided for subsequent preparation of the high-quality foamed aluminum; the controller accurately controls the air pump and the air cylinder in different time periods, and a unique air blowing and baffle position adjusting strategy is achieved. In the first time period, the air pump works at the high first output air pressure, meanwhile, the baffle is located at the low first position, more gas can be rapidly injected into the resistance furnace, and molten aluminum is promoted to be rapidly foamed. And in a second time period after the first time period, the air pump works at a lower second output air pressure, the baffle rises to a higher second position, and the gas injection speed is slowed down, so that stable growth and distribution of the bubbles are facilitated, the bubbles are prevented from being excessively gathered or broken, and the foamed aluminum with lower density and more uniform bubble structure is prepared.

Description

Technical Field

[0001] This application relates to the technical field of equipment for preparing low-density aluminum foam, and particularly to an equipment for preparing low-density aluminum foam. Background Art

[0002] Boron carbide contains boron-10 isotope. Boron-10 has the characteristics of high neutron absorption cross-section, high neutron capture cross-section, wide capture energy spectrum, and its thermal cross-section is as high as , second only to a few elements such as gadolinium (Gd), samarium (Sm), cadmium (Cd), etc., and can absorb a large amount of neutrons. Moreover, boron carbide can absorb a large amount of neutrons without forming any radioactive isotopes, and can well control the rate of nuclear fission.

[0003] If boron element is directly applied to the control elements or nuclear shielding materials of the reactor, it will cause component damage due to the lithium atoms generated by the capture reaction not being accommodated in the unit cell, and the release of helium gas will also cause material swelling, affecting the neutron shielding effect. While boron carbide as a substitute for elemental boron can solve this problem.

[0004] Aluminum foam itself has many advantages such as light weight and large specific surface area, but its mechanical strength is relatively low. Boron carbide has a density similar to that of aluminum, and has a high elastic modulus, hardness, excellent chemical stability, etc. Adding it to aluminum foam can not only improve the mechanical strength and other properties of aluminum foam, but also give full play to its excellent neutron absorption performance, making the aluminum foam composite material have better application value in the nuclear industry. However, in the prior art, boron carbide is added to the preparation process of aluminum foam by the melt method, and this process method is difficult to operate, has high temperature control requirements and a complex cooling process. Summary of the Invention

[0005] In an exemplary embodiment of this application, an equipment for preparing low-density aluminum foam is provided to complete the preparation of aluminum foam material containing boron carbide by the blowing method and ensure the performance of the aluminum foam material.

[0006] This application provides an equipment for preparing low-density aluminum foam, which includes: a heat treatment device and a blowing treatment device; The heating treatment device includes a motor, a heating furnace, and a vacuum pump. An accommodation space for accommodating aluminum ingots and boron carbide is formed inside the heating furnace. An end cover is provided at the top of the heating furnace, and the end cover is used to seal the accommodation space. A feed port is provided on the end cover, and the feed port is used to inject boron carbide into the accommodation space. The output end of the motor is connected to a stirring paddle, and the stirring paddle is located inside the accommodation space. The stirring paddle is driven by the motor to rotate inside the accommodation space. The vacuum pump is connected to the accommodation space through a pipeline, and the vacuum pump is used to extract the gas in the space inside the heating furnace. The heating treatment device is used to prepare aluminum liquid containing boron carbide; The blowing treatment device includes a resistance furnace, a blowing pipe, an aluminum liquid delivery pipe, a baffle, an air pump, a cylinder, and a controller. A furnace cover is provided at the top of the resistance furnace. The air outlet end of the air pump is connected to the blowing pipe, and the blowing pipe is used to deliver air flow into the resistance furnace. The baffle is arranged inside the resistance furnace and is arranged vertically. The output end of the cylinder is connected to the baffle and the baffle is driven by the cylinder to move vertically inside the resistance furnace. The end of the blowing pipe located inside the resistance furnace is located below the baffle. The end of the aluminum liquid delivery pipe is connected inside the resistance furnace, and the aluminum liquid delivery pipe is used to deliver aluminum liquid. The controller is connected to the air pump and the cylinder, and the controller is configured to: Drive the air pump to work at a first output air pressure during a first time period, and drive the cylinder to operate and drive the baffle to be in a first position; Drive the air pump to work at a second output air pressure during a second time period after the first time period, and drive the cylinder to operate and drive the baffle to be in a second position; The second output air pressure is less than the first output air pressure. The time length of the second time period is greater than the time length of the first time period. The height distance in the vertical direction between the bottom of the baffle in the first position and the bottom wall of the resistance furnace is less than the height distance in the vertical direction between the bottom of the baffle in the second position and the bottom wall of the resistance furnace.

[0007] Further, the baffle is arranged close to the furnace cover, and a gap is formed between the bottom of the baffle and the bottom of the resistance furnace.

[0008] Further, the operating temperature of the resistance furnace is between 620°C and 650°C.

[0009] Further, the first output air pressure is 1.5 - 2 times the second output air pressure.

[0010] Further, a chute for connecting the baffle is arranged inside the resistance furnace, and the chute extends vertically.

[0011] The embodiments of the present application have the following beneficial effects: The motor drives the stirring paddle to rotate in the accommodation space of the heating furnace, which can fully mix the aluminum ingot and boron carbide, ensuring that boron carbide is evenly dispersed in the aluminum liquid, laying a foundation for the subsequent preparation of high-quality aluminum foam. The vacuum pump can extract the gas in the heating furnace to create a low-pressure environment, reducing the influence of impurity gases on the aluminum liquid and improving the purity of the aluminum liquid. Through the precise control of the air pump and the cylinder by the controller at different time periods, a unique gas blowing and baffle position adjustment strategy is achieved. In the first time period, the air pump works at a higher first output air pressure, and at the same time, the baffle is located at a lower first position, which can quickly inject more gas into the resistance furnace, prompting the aluminum liquid to foam quickly. In the second time period after the first time period, the air pump works at a lower second output air pressure, and the baffle rises to a higher second position. At this time, the gas injection speed slows down, which is beneficial to the stable growth and distribution of bubbles, avoiding excessive aggregation or rupture of bubbles, and thus preparing aluminum foam with a lower density and a more uniform bubble structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0013] Figure 1 FIG. 1 schematically shows the structure of a heat treatment device for a preparation device for low-density aluminum foam provided by an embodiment of the present application; Figure 2 FIG. 2 schematically shows the structure of a gas blowing treatment device for a preparation device for low-density aluminum foam provided by an embodiment of the present application; Figure 3 FIG. 3 schematically shows the system connection diagram of a preparation device for low-density aluminum foam provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application.

[0015] To further illustrate the technical solutions provided by the embodiments of the present application, the following will be described in detail in conjunction with the accompanying drawings and specific implementation manners. Although the embodiments of the present application provide method operation steps as shown in the following embodiments or drawings, based on routine or non-creative labor, the method may include more or fewer operation steps. In steps where there is no necessary causal relationship logically, the execution order of these steps is not limited to the execution order provided by the embodiments of the present application.

[0016] Referring Figures 1-3 As shown, the present application provides a preparation device for low-density aluminum foam, which includes: a heat treatment device 10 and a blowing treatment device 20.

[0017] The heat treatment device 10 includes a motor 11, a heating furnace 12 and a vacuum pump 13. An accommodation space for accommodating aluminum ingots and boron carbide is formed inside the heating furnace 12. A end cover 14 is provided at the top of the heating furnace 12, and the end cover 14 is used to seal the accommodation space. A feed port 141 is provided on the end cover 14, and the feed port 141 is used to inject boron carbide into the accommodation space.

[0018] The output end of the motor 11 is connected to a stirring paddle 111. The stirring paddle 111 is located inside the accommodation space and is driven by the motor 11 to rotate inside the accommodation space. The vacuum pump 13 is connected to the accommodation space through a pipeline, and the vacuum pump 13 is used to extract the gas in the space inside the heating furnace 12. The heat treatment device 10 is used to prepare aluminum liquid including boron carbide.

[0019] The heating furnace 12 forms an accommodation space specifically for accommodating aluminum ingots and boron carbide inside. The end cover 14 provided at the top plays a sealing role, which can effectively prevent foreign impurities from entering, maintain the stability of the internal environment, and ensure that the aluminum ingots are not oxidized during the heating process, etc.

[0020] The feed port 141 on the end cover 14 is ingeniously designed, which is convenient for accurately injecting boron carbide into the accommodation space, ensuring the convenience and accuracy of raw material addition.

[0021] The output end of the motor 11 is connected to the stirring paddle 111 located inside the accommodation space. The motor 11 serves as a power source to drive the stirring paddle 111 to rotate inside the accommodation space. During the heating and melting process of the aluminum ingots, the stirring paddle 111 continuously stirs, enabling the aluminum liquid and boron carbide to be fully mixed, ensuring that the boron carbide is evenly dispersed in the aluminum liquid, providing a uniform raw material basis for the subsequent preparation of high-quality aluminum foam, and avoiding the instability of the aluminum foam quality caused by uneven component distribution.

[0022] The vacuum pump 13 is connected to the accommodation space through a pipeline. Its key role is to extract the gas in the space inside the heating furnace 12 to create a low-pressure environment.

[0023] At low pressure, the impurity gases generated during the heating process of aluminum ingots are more easily discharged, reducing the influence of impurities on the purity of molten aluminum, improving the quality of molten aluminum, and thus contributing to improving the performance of the finally prepared aluminum foam.

[0024] The air-blowing treatment device 20 includes a resistance furnace 21, a blow pipe 22, a molten aluminum delivery pipe 23, a baffle 24, an air pump 25, a cylinder 26, and a controller 27. A furnace cover is provided on the top of the resistance furnace 21. The air outlet end of the air pump 25 is connected to the blow pipe 22, and the blow pipe 22 is used to deliver air flow into the resistance furnace 21. The end of the blow pipe 22 is located below the baffle 24, and the operating temperature of the resistance furnace 21 is between 620°C and 650°C.

[0025] The baffle 24 is arranged in the resistance furnace 21 and is arranged vertically. A chute for connecting the baffle 24 is arranged in the resistance furnace 21, and the chute extends vertically. The baffle 24 is arranged close to the furnace cover. The bottom of the baffle 24 is spaced from the bottom of the resistance furnace 21 to form a gap. The output end of the cylinder 26 is connected to the baffle 24, and the baffle 24 is driven by the cylinder 26 to move vertically in the resistance furnace 21. The end of the blow pipe 22 located in the resistance furnace 21 is located below the baffle 24. The end of the molten aluminum delivery pipe 23 is connected to the inside of the resistance furnace 21, and the molten aluminum delivery pipe 23 is used to deliver molten aluminum.

[0026] The controller 27 is connected to the air pump 25 and the cylinder 26, and the controller 27 is configured to: drive the air pump 25 to work at a first output air pressure during a first time period, and drive the cylinder 26 to operate and drive the baffle 24 to be in a first position.

[0027] During the first time period, the controller 27 drives the air pump 25 to work at a first output air pressure, which is relatively high and provides strong power for the subsequent foaming process. At the same time, the controller 27 drives the cylinder 26 to operate, driving the baffle 24 to be in the first position. In this position, the height distance between the bottom of the baffle 24 and the bottom wall of the resistance furnace 21 in the vertical direction is relatively small, meaning that the baffle 24 is in a lower position.

[0028] The core purpose of this stage is to quickly promote the foaming of the molten aluminum containing boron carbide. On the one hand, the relatively high first output air pressure enables the air pump 25 to quickly deliver a large amount of gas into the resistance furnace 21 through the blow pipe 22. On the other hand, the baffle 24 being in a lower position can effectively block the upward diffusion of the air flow and guide the air flow to concentrate in the bottom area of the resistance furnace 21 to fully contact the molten aluminum.

[0029] Since boron carbide is uniformly dispersed in the molten aluminum, under the strong impact of the air flow, bubble nuclei are extremely easy to form around the boron carbide particles, and a large number of bubble nuclei are rapidly generated, laying a foundation for the subsequent formation of a rich and uniform bubble structure.

[0030] At this stage, driving the air pump 25 to work with the first output air pressure can provide a high-speed air flow, and the rapid contact between the high-speed air flow and the molten aluminum enables the foaming process to start and proceed rapidly in a short time, greatly shortening the overall preparation time.

[0031] Under the action of the air flow, the boron carbide particles become the cores of a large number of bubbles, and these bubbles have a high density and uniformity at the initial stage. Due to the guiding effect of the baffle 24 on the air flow, the bubbles are evenly distributed at the bottom of the resistance furnace 21, avoiding the situation of too many or too few local bubbles.

[0032] The good initial bubble structure formed in the first time period provides a solid guarantee for the stable growth and further uniform distribution of the bubbles in the subsequent second time period, playing a key initial promoting role in finally preparing the high-quality, low-density and uniformly structured boron carbide-containing aluminum foam material.

[0033] After the first time period, in the second time period, drive the air pump 25 to work with the second output air pressure, and drive the cylinder 26 to operate and drive the baffle 24 to be in the second position.

[0034] The second output air pressure is less than the first output air pressure, the first output air pressure is 1.5 - 2 times the second output air pressure, the time length of the second time period is greater than the time length of the first time period, and the height distance in the vertical direction between the bottom of the baffle 24 in the first position and the bottom wall of the resistance furnace 21 is less than the height distance in the vertical direction between the bottom of the baffle 24 in the second position and the bottom wall of the resistance furnace 21.

[0035] In the second time period after the first time period, the controller 27 drives the air pump 25 to work with the second output air pressure, which is significantly lower than the first output air pressure, and the output air flow is relatively stable and gentle.

[0036] At the same time, the controller 27 drives the cylinder 26 to operate, driving the baffle 24 to move to the second position, where the height distance in the vertical direction between the bottom of the baffle 24 and the bottom wall of the resistance furnace 21 is larger, that is, the baffle 24 is in a higher position.

[0037] The main purpose of the control actions in the second time period is to promote the stable growth and uniform distribution of the bubbles formed in the early stage. The lower second output air pressure can prevent the bubbles formed in the early stage from bursting or merging excessively due to excessive air flow impact.

[0038] The baffle 24 rises to a higher position in this second time period, increasing the gas circulation space in the resistance furnace 21, enabling the bubbles to have a wider space to adjust their positions during the rising process, further promoting the uniform distribution of the bubbles and avoiding local bubble aggregation. Utilize the heterogeneous nucleation effect of the boron carbide particles to form uniformly distributed initial pores. The time of this stage is short to avoid excessive growth or local merging of the bubbles caused by continuous injection of high-pressure gas.

[0039] From the perspective of bubble growth, the steady low-pressure airflow provides a stable growth environment for the bubbles, allowing them to gradually expand at a reasonable rate and avoiding instability of the bubble structure caused by sudden changes in air pressure.

[0040] In terms of bubble distribution, after the baffle 24 is raised, the flow path and space of the gas in the resistance furnace 21 change, guiding the bubbles to be more evenly dispersed in the aluminum liquid during the rising process, effectively reducing the bubble aggregation phenomenon.

[0041] This optimization of bubble growth and distribution in the second time period, combined with the good initial bubble structure formed in the first time period, ultimately successfully prepared a high-quality, low-density boron carbide-containing foam aluminum material with uniform bubble structure, significantly improving the performance of the foam aluminum material.

[0042] The length of the second time period is longer than that of the first time period. The purpose of this setting is that the first time period focuses on rapid gas injection to promote rapid foaming of the aluminum liquid and form a large number of initial bubbles. The second time period is longer to provide these initial bubbles with ample time for stable growth. Because bubble growth is not completed instantly, it takes enough time to gradually expand to a suitable size under a stable low-pressure environment. A long first time period will cause the bubbles to grow excessively or even burst under unstable high pressure, while a long enough second time period allows the bubbles to achieve sufficient and reasonable growth under suitable conditions.

[0043] The baffle 24 is at a higher position in the second time period, and the gas circulation space in the resistance furnace 21 is increased. The bubbles need more time to adjust their positions in this wide space to achieve uniform distribution. In a shorter second time period, the bubbles do not have enough time to move and disperse fully, which may easily cause local bubble aggregation or uneven distribution. A longer second time period gives the bubbles enough travel and time to disperse more evenly in the aluminum liquid during the rising process.

[0044] Sufficient growth time makes the bubble wall thickness more uniform and the bubble shape more regular. Long-term growth under stable low pressure slowly balances the internal pressure of the bubble with the external aluminum liquid pressure, avoiding problems such as too thin or too thick bubble walls and deformed shapes caused by insufficient growth time, thereby optimizing the bubble microstructure inside the foam aluminum.

[0045] Since the bubbles have enough time to be evenly distributed, the density and performance of the prepared boron carbide-containing aluminum foam material are more consistent in different parts.

[0046] The height distance between the bottom of the baffle 24 at the first position and the bottom wall of the resistance furnace 21 in the vertical direction is smaller than the height distance between the bottom of the baffle 24 at the second position and the bottom wall of the resistance furnace 21 in the vertical direction.

[0047] In the first time period, the air pump 25 operates at a relatively high first output air pressure. At this time, the baffle 24 is in a relatively low first position, aiming to relatively partition the space inside the resistance furnace 21, so that the high-speed air flow blown out by the air blowing pipe 22 can fully contact the molten aluminum in a relatively small space. This can effectively concentrate the impact force of the air flow, promote the rapid foaming of the molten aluminum, and form a large number of initial bubbles in a short time.

[0048] The low position of the baffle 24 in cooperation with the high-pressure air flow greatly improves the foaming efficiency. The high-speed air flow violently mixes with the molten aluminum in the restricted space, accelerating the dispersion of gas in the molten aluminum, and a large number of bubbles are rapidly generated, laying a rich bubble foundation for the subsequent formation of aluminum foam. At the same time, due to the relatively small space, the bubbles are restricted to a certain extent in the initial formation stage, and their size and distribution are relatively uniform, avoiding the uneven initial distribution caused by the dispersion of the air flow in a large space.

[0049] In the second time period, the air pump 25 switches to a relatively low second output air pressure. The baffle 24 rises to a relatively high second position, aiming to expand the gas circulation space inside the resistance furnace 21.

[0050] To provide a wider moving range for the bubbles formed in the early stage, so that the bubbles have enough space to adjust their positions during the rising process, thereby achieving uniform distribution. At the same time, in a low-pressure environment, a larger space is required to ensure the stable growth of the bubbles, avoiding the mutual extrusion, merging or rupture of the bubbles due to the cramped space.

[0051] The baffle 24 at a relatively high position enables the bubbles to move freely in a larger space during the rising process, gradually adjust their positions, and achieve uniform distribution of the bubbles in the molten aluminum.

[0052] This process optimizes the bubble structure inside the aluminum foam, making the bubble density and distribution in different parts of the material more consistent. The finally prepared boron carbide-containing aluminum foam material shows higher consistency in terms of properties such as density and strength, significantly improving the quality and application value of the material.

[0053] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to this application. It should be understood that each process and / or block in the flowchart and / or block diagram, and the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in one Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0054] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction device that implements the functions specified in one or more of the processes Figure 1 one or more processes and / or blocks Figure 1 and / or blocks specified in the block diagram.

[0055] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, so that the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one or more of the processes Figure 1 one or more processes and / or blocks Figure 1 and / or blocks specified in the block diagram.

[0056] It will be apparent to those skilled in the art that various modifications and variations can be made to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

Claims

1. A preparation device for low-density foamed aluminum, characterized in that: It includes: Heating treatment device and air blowing treatment device; The heating treatment device comprises a motor, a heating furnace and a vacuum pump. A storage space for accommodating aluminum ingots and boron carbide is formed in the heating furnace. An end cover is arranged on the top of the heating furnace, and the end cover is used to seal the storage space. A feed port is arranged on the end cover, and the feed port is used to inject boron carbide into the storage space. The output end of the motor is connected to a stirring paddle, and the stirring paddle is located in the storage space. The stirring paddle is driven by the motor to rotate in the storage space. The vacuum pump is connected to the storage space through a pipeline connection, and the vacuum pump is used to extract gas from the space in the heating furnace. The heating treatment device is used to prepare aluminum liquid containing boron carbide. The air blowing treatment device comprises a resistance furnace, an air blowing pipe, an aluminum liquid conveying pipe, a baffle, an air pump, a cylinder, and a controller. A furnace cover is arranged on the top of the resistance furnace. The air outlet end of the air pump is connected to the air blowing pipe. The air blowing pipe is used to convey airflow into the resistance furnace. The baffle is arranged in the resistance furnace and arranged in a vertical direction. The output end of the cylinder is connected to the baffle and the baffle is driven by the cylinder to move in a vertical direction in the resistance furnace. The end of the air blowing pipe located in the resistance furnace is located below the baffle. The end of the aluminum liquid conveying pipe is connected to the resistance furnace. The aluminum liquid conveying pipe is used to convey aluminum liquid. The controller is connected to the air pump and the cylinder. The controller is configured as follows: In a first time period, the air pump is driven to operate at a first output air pressure, and the air cylinder is driven to operate and drive the baffle to be located at a first position; In a second time period after the first time period, the air pump is driven to operate at a second output air pressure, and the air cylinder is driven to operate and drive the baffle to be located at a second position; The second output gas pressure is lower than the first output gas pressure, the length of the second time period is longer than the length of the first time period, and the vertical distance between the bottom of the baffle at the first position and the bottom wall of the resistance furnace is shorter than the vertical distance between the bottom of the baffle at the second position and the bottom wall of the resistance furnace.

2. The preparation equipment for low-density foamed aluminum according to claim 1, characterized in that: The baffle is arranged close to the furnace cover, and the bottom of the baffle is spaced apart from the bottom of the resistance furnace to form a gap.

3. The preparation equipment for low-density foamed aluminum according to claim 2, characterized in that: The operating temperature of the resistance furnace is between 620°C and 650°C.

4. The preparation equipment for low-density foamed aluminum according to claim 1, characterized in that: The first output air pressure is 1.5-2 times of the second output air pressure.

5. The preparation equipment for low-density foamed aluminum according to claim 1, characterized in that: A slide groove for connecting the baffle is arranged in the resistance furnace, and the slide groove is extended in the vertical direction.

Images