Centrifugal atomizer and method of controlling the same

Abstract

The application discloses a centrifugal atomizer and a control method thereof. The centrifugal atomizer comprises an atomization chamber, a centrifugal rotating disc, a flow guide pipe, a heater, an ultrasonic generator, a detection assembly and an alarm. The atomization chamber is filled with inert gas. The centrifugal rotating disc is rotatably arranged in the atomization chamber. The flow guide pipe, which is arranged opposite to the center of the centrifugal rotating disc, penetrates through the top wall of the atomization chamber and is used for guiding the alloy melt. The heater is used for preheating the centrifugal rotating disc before the atomization work starts, so as to remove the impurities such as the adsorbed gas on the surface of the centrifugal rotating disc and enhance the wettability. In the atomization work process, the ultrasonic field is used for destroying the oxide film of the alloy melt and strengthening the wettability of the alloy melt and the centrifugal rotating disc. The alarm can alarm in time when the wettability is abnormal, so as to prevent the wettability of the alloy melt and the centrifugal rotating disc from being poor in the atomization process. The alarm can also alarm in time when the centrifugal rotating disc is broken, so as to stop the delivery of the alloy melt, avoid the alloy melt from directly falling on the ultrahigh-speed motor and causing damage to the motor, and avoid the production loss.

Description

Technical Field

[0001] This application relates to the field of metal atomization technology, and in particular to a centrifugal atomizer and its control method. Background Technology

[0002] Facing the demands of upgrading traditional manufacturing and supporting the development of high-end manufacturing, additive manufacturing technology, as one of the advanced digital manufacturing technologies, helps to improve the manufacturing capabilities of fields such as aerospace, rail transportation, nuclear industry, and marine engineering equipment. Raw materials for metal additive manufacturing are the foundation of the entire industry. Currently, powder preparation technology applicable to metal additive manufacturing has evolved from traditional powder metallurgy. Rotary centrifugal atomization produces metal powders with high sphericity, narrow particle size distribution, and virtually no hollow or satellite spheres, giving it significant potential advantages in the production of powder raw materials for metal additive manufacturing.

[0003] Currently, it is generally assumed that the alloy melt and the centrifugal disc are completely wetted, and the centrifugal disc efficiently transfers mechanical energy to the alloy melt. However, for typical additive manufacturing metal raw materials such as high-temperature aluminum alloys and titanium alloys, they are prone to react with oxygen in the molten state to form an oxide film. Furthermore, the oxygen partial pressure of the oxide cannot be engineered using existing vacuum technology. The oxide film they produce is also difficult to destroy by heating within the atomization process parameters. The presence of the oxide film will greatly reduce the wettability between the molten metal and the centrifugal disc, causing the centrifugal disc to be unable to effectively transfer mechanical energy to the alloy melt, resulting in problems such as coarse powder particle size and many irregularly shaped powders. In severe cases, it may even prevent the alloy melt from being atomized. Furthermore, when centrifugal discs are used for atomizing additive manufacturing of high-temperature alloy melts, various problems such as severe temperature gradients, high temperatures, and the corrosiveness of the alloy melt can cause the centrifugal discs to break, disintegrate, or react with the alloy melt and disappear. In such cases, the residual part of the centrifugal disc and the overall dynamic balance of the ultra-high-speed motor often do not change significantly, and methods such as vibration level detection become ineffective. If the problem is not detected immediately, the alloy melt will fall directly onto the ultra-high-speed motor, causing damage to the ultra-high-speed motor and resulting in significant production losses.

[0004] Therefore, it is necessary to provide a new centrifugal atomizer and its control method to solve the above-mentioned technical problems. Summary of the Invention

[0005] The main objective of this application is to provide a centrifugal atomizer and its control method, which aims to solve the problems of the oxide film on the surface of the alloy melt reducing the wettability between the molten metal and the centrifugal disc, causing the centrifugal disc to be unable to effectively transfer mechanical energy to the alloy melt, resulting in large powder particle size and many irregular powders, as well as the problem of the alloy melt corroding the centrifugal disc, causing the alloy melt to fall onto the ultra-high speed motor and damage the ultra-high speed motor.

[0006] To achieve the above objectives, this application proposes a centrifugal atomizer and its control method. The centrifugal atomizer includes an atomizing chamber, a centrifugal disc, a guide tube, a heater, an ultrasonic generator, a detection component, and an alarm. The atomizing chamber is filled with inert gas. The centrifugal disc is rotatably disposed within the atomizing chamber. The guide tube passes through the top wall of the atomizing chamber and is positioned directly opposite the center of the centrifugal disc. The guide tube is used to introduce molten alloy. The heater is slidably connected to the inner wall of the atomizing chamber and can slide onto the centrifugal disc. The centrifugal turntable is heated; the ultrasonic generator is slidably connected to the inner wall of the atomization chamber, and the ultrasonic generator can slide above the centrifugal turntable to form an ultrasonic field at the centrifugal turntable; the detection end of the detection component is set towards the centrifugal turntable, and the detection component is used to detect the integrity of the centrifugal turntable and the uniformity of the alloy melt coverage on the centrifugal turntable; the alarm is electrically connected to the detection component, and the alarm is used to sound an alarm when the detection component detects that the centrifugal turntable is damaged or that the alloy melt coverage on the centrifugal turntable is uneven.

[0007] In one embodiment, the centrifugal turntable includes an atomizing disc and a support shaft connected together, the atomizing disc and the support shaft being coaxially arranged, and the support shaft being connected to the output shaft of an ultra-high-speed motor.

[0008] In one embodiment, the atomizing disk is made of ceramic material or refractory hard metal material.

[0009] In one embodiment, the surface of the atomizing disk is provided with a corrugated structure, and the size of the crest or trough of the corrugated structure does not exceed 0.2 mm.

[0010] In one embodiment, the heater is disc-shaped, and the diameter of the heater is larger than the equivalent diameter of the atomizing disc; the thickness of the heater is B, and the vertical distance between the end of the guide tube and the atomizing disc is H, wherein B≤H / 3.

[0011] In one embodiment, the heater is a resistance heating element.

[0012] In one embodiment, a clearance hole is formed in the middle of the ultrasonic generator, and when the ultrasonic generator is located above the centrifugal turntable, the clearance hole faces the guide pipe; or, there are multiple ultrasonic generators, which are spaced apart circumferentially along the centrifugal turntable, and each ultrasonic generator is inclined and its working head faces the centrifugal turntable.

[0013] In addition, this application also provides a centrifugal atomizer control method, which is applied to the centrifugal atomizer described above, and the centrifugal atomizer control method includes: Move the heater above the centrifugal disc and heat the centrifugal disc; Once the centrifuge disc has been cleaned, turn off the heater and move it away from above the centrifuge disc. Move the ultrasonic generator above the centrifugal disc and start it to control the centrifugal disc to begin atomization. The detection component acquires images of the centrifuge disc in real time and determines whether the centrifuge disc is damaged. If so, the alarm will send an alarm message.

[0014] In one embodiment, after the step of the detection component acquiring images of the centrifuge disc in real time and determining whether the centrifuge disc is damaged, the method further includes: If the centrifugal turntable is not damaged within the preset working time T, then it is determined whether the alloy melt evenly covers the centrifugal turntable. If not, the ultrasonic generator is controlled to work for a preset working time T, and the detection component is executed to acquire images of the centrifugal turntable in real time and determine whether the centrifugal turntable is damaged.

[0015] In one embodiment, the theoretical time required for the alloy melt to fall from the center of the centrifugal turntable to leave the centrifugal turntable is defined as t, where T > 5t.

[0016] In this technical solution, before atomization begins, the detection component is activated and put into operation. The heater is moved directly above the centrifugal turntable, and the heating rate, temperature, and time are controlled. After heating, the heater moves away from the centrifugal turntable. Subsequently, the ultrasonic generator is moved above the centrifugal turntable. After atomization begins, the ultrasonic generator is activated and operates for a preset time before being turned off. During atomization, the detection component performs real-time monitoring. If the centrifugal turntable is found to be damaged, an alarm is triggered to the operator, reminding them to take immediate protective measures. If the centrifugal turntable is found to be normal, the wettability between the centrifugal turntable and the alloy melt is further assessed, i.e., the uniformity of the alloy melt coverage on the centrifugal turntable. If the wettability between the turntable and the alloy melt is found to be poor, atomization cannot proceed smoothly, the alarm is triggered to the operator, and the ultrasonic generator is restarted and operates for a preset time before being turned off.

[0017] Therefore, before the centrifugal atomizer in this application begins atomization, the centrifugal disc is preheated by a heater to remove impurities such as adsorbed gases from its surface, thereby enhancing the wettability between the centrifugal disc and the alloy melt. During atomization, an ultrasonic field is generated at the centrifugal disc using an ultrasonic generator to break down the oxide film on the alloy melt to be atomized, and a pulsed ultrasonic field is used to further enhance the wettability between the alloy melt and the centrifugal disc. This prevents poor wettability between the alloy melt and the centrifugal disc during atomization, solving the problem of insufficient wettability between the centrifugal disc and the alloy melt caused by unfavorable factors such as oxide films and adsorbed gases at the beginning of atomization or during atomization. Simultaneously, an alarm is used to alert the operator if atomization is not progressing smoothly. Furthermore, in extreme cases (such as when the centrifugal disc breaks), an immediate alarm is triggered, and the supply of alloy melt to the centrifugal disc is stopped, preventing the alloy melt from falling directly onto the high-speed motor and causing damage, thus avoiding production losses. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a centrifugal atomizer in one embodiment of this application; Figure 2 This is a schematic diagram of the centrifugal turntable in an embodiment of this application; Figure 3 This is a schematic diagram of the ultrasonic generator in the embodiments of this application; Figure 4 This is a schematic diagram of the working head of the ultrasonic generator in the embodiments of this application; Figure 5 This is a schematic flowchart of a centrifugal atomizer control method in one embodiment of this application; Figure 6 This is a flowchart illustrating the centrifugal atomizer control method in another embodiment of this application.

[0020] Explanation of icon numbers: 1. Atomizing chamber; 2. Centrifugal turntable; 21. Atomizing disc; 22. Support shaft; 23. Corrugated structure; 3. Guide tube; 4. Heater; 5. Ultrasonic generator; 51. Bracket; 6. Detection components; 7. Alarm; 8. Guide rail; 91. Industrial control computer; 92. Computer.

[0021] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0023] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0024] Furthermore, the use of terms such as "first," "second," etc., in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, 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.

[0025] In this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean 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.

[0026] Furthermore, the technical solutions of the various embodiments of this application can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this application.

[0027] like Figures 1 to 4As shown in one embodiment of this application, the centrifugal atomizer includes an atomizing chamber 1, a centrifugal disc 2, a guide tube 3, a heater 4, an ultrasonic generator 5, a detection component 6, and an alarm 7. The atomizing chamber 1 is filled with inert gas. The centrifugal disc 2 is rotatably disposed within the atomizing chamber 1. The guide tube 3 passes through the top wall of the atomizing chamber 1 and is positioned directly opposite the center of the centrifugal disc 2. The guide tube 3 is used to introduce the alloy melt. The heater 4 is slidably connected to the inner wall of the atomizing chamber 1 and can slide above the centrifugal disc 2 to add heat. A heated centrifugal turntable 2; an ultrasonic generator 5 is slidably connected to the inner wall of the atomization chamber 1, and the ultrasonic generator 5 can slide above the centrifugal turntable 2 to form an ultrasonic field at the centrifugal turntable 2; the detection end of the detection component 6 is set towards the centrifugal turntable 2, and the detection component 6 is used to detect the integrity of the centrifugal turntable 2 and the uniformity of the alloy melt coverage on the centrifugal turntable 2; an alarm 7 is electrically connected to the detection component 6, and the alarm 7 is used to alarm when the detection component 6 detects damage to the centrifugal turntable 2 or when the alloy melt coverage is uneven.

[0028] In the above embodiment, before the atomization operation begins, the detection component 6 is turned on and put into operation; the heater 4 is moved directly above the centrifugal turntable 2, and the heating rate, heating temperature, and heating time of the heater 4 are controlled. After heating is completed, the heater 4 moves away from directly above the centrifugal turntable 2; then the ultrasonic generator 5 is moved above the centrifugal turntable 2; after atomization begins, the ultrasonic generator 5 is turned on and continues to operate for a preset time before being turned off; during the atomization process, the centrifugal turntable 2 is driven to rotate by an ultra-high-speed motor, and the detection component 6 performs real-time detection. If the centrifugal turntable 2 is found to be damaged, an alarm message is sent to the operator using the alarm 7 to remind the operator to take immediate protective measures; if the centrifugal turntable 2 is found to be normal, the wettability of the centrifugal turntable 2 and the alloy melt is further determined, that is, the uniformity of the alloy melt coverage on the centrifugal turntable 2. If the wettability of the turntable and the alloy melt is found to be poor, the atomization operation cannot proceed smoothly. An alarm message is sent to the operator using the alarm 7 to remind the operator that the atomization operation is abnormal. At the same time, the ultrasonic generator 5 is turned on again and continues to operate for a preset time before being turned off.

[0029] Therefore, before the atomization operation begins, the centrifugal atomizer in this application preheats the centrifugal disc 2 with heater 4 to remove impurities such as adsorbed gases from its surface, thereby enhancing the wettability between the alloy melt and the centrifugal disc 2. During the atomization process, an ultrasonic field is formed at the centrifugal disc 2 by ultrasonic generator 5 to destroy the oxide film of the alloy melt to be atomized, and the pulsed ultrasonic field is used to enhance the wettability between the alloy melt and the centrifugal disc 2, preventing poor wettability between the alloy melt and the centrifugal disc 2 during atomization. This solves the problem of insufficient wettability between the centrifugal disc 2 and the alloy melt caused by unfavorable factors such as oxide film and adsorbed gases during the initial stage or process of atomization. Furthermore, in extreme cases, if the centrifugal disc 2 breaks, an alarm is triggered immediately, and the supply of alloy melt to the centrifugal disc 2 is stopped, preventing the alloy melt from falling directly onto the ultra-high-speed motor and causing damage, thus avoiding production losses.

[0030] The mechanical equipment typically uses a computer 92 and an industrial control computer 91 to control various electrical components. The alarm 7 and the detection component 6 are both electrically connected to the computer 92. The detection component 6 can be a camera, with its viewfinder facing the centrifugal turntable 2. The camera is positioned outside the atomization chamber 1, and a transparent window is provided in the atomization chamber 1 corresponding to the camera's viewfinder position to prevent damage to the camera. In practical applications, a high-definition camera is preferred, and feedback information from images captured by the high-definition camera is recognized during the atomization process. The centrifugal atomizer in this application also includes a guide rail mechanism 8, which is fixed to the top of the atomization chamber 1 by a support rod. The guide rail mechanism 8 is used for the horizontal movement of the ultrasonic generator 5 and the heating element.

[0031] The high-definition camera remains operational throughout the atomization process, acquiring images of the liquid film spreading on the surface of the centrifugal disc 2 at a set sampling frequency and inputting them into the computer 92. The computer 92 compares these images with those from a normal atomization process. If the difference is significant, it indicates that atomization is not proceeding smoothly, and the computer 92 sends an ultrasonic atomizer start command to the industrial control computer 91. The industrial control computer 91 then activates the ultrasonic generator 5, which operates for the preset duration. Simultaneously, the computer 92 issues an alarm command to control the alarm 7, which then sends an alarm message to the operator, notifying them of an abnormality in the atomization process. If the difference is minimal, it indicates that atomization is proceeding smoothly, and the computer 92 does not issue any action commands. Furthermore, if the centrifugal disc 2 breaks, the images captured by the high-definition camera will be significantly different from those when the centrifugal disc 2 is present. The computer 92 can then determine that the centrifugal disc 2 has broken and sends a breakage message to the operator via the alarm 7. The operator must then take measures to protect the high-speed motor and its components, and simultaneously activate the centrifugal atomizer's protective measures. The protection mechanism is activated by the industrial control computer 91 to prevent the high-temperature alloy melt from corroding the ultra-high speed motor and avoid damage to the ultra-high speed motor.

[0032] In one embodiment, please refer to [reference needed]. Figure 2 The centrifugal turntable 2 is T-shaped and includes an atomizing disc 21 and a support shaft 22 connected together. The atomizing disc 21 and the support shaft 22 are coaxially arranged, and the support shaft 22 is connected to the output shaft of the ultra-high-speed motor. The centrifugal turntable 2 includes an atomizing disc 21 and a support shaft 22, which is fastened to the ultra-high-speed motor via connectors such as tool holder assemblies. The support shaft 22 is fastened to the ultra-high-speed motor to drive the centrifugal turntable 2 to rotate at ultra-high speed. The support shaft 22 and the atomizing disc 21 can be integrally machined or assembled and fixed together. The length and diameter of the support shaft 22 can be determined according to the specific requirements of the working speed and connectors (couplings, tool holders, etc.). For example, as the speed increases, the diameter of the support shaft 22 increases accordingly. The equivalent diameter of the centrifugal turntable 2 is between 20mm and 60mm, and the thickness is between 3mm and 6mm.

[0033] The surface of the centrifugal turntable 2 is made of ceramic material or refractory hard metal material. The surface of the turntable is designed with a corrugated structure 23 to improve the efficiency of the centrifugal turntable 2 in transmitting mechanical energy to the alloy melt and to enhance the ultrasonic effect. The size of the wave crest or trough does not exceed 0.2 mm.

[0034] In one embodiment, the atomizing disk 21 is made of ceramic material or refractory hard metal material. It is resistant to alloy melts such as aluminum alloys with melting points above 500°C, allowing it to withstand high temperatures while preventing corrosion from the alloy melt, thus avoiding contamination of the alloy material to be atomized.

[0035] In one embodiment, the surface of the atomizing disk 21 is provided with a corrugated structure 23, the size of the crests or troughs of the corrugated structure 23 not exceeding 0.2 mm. The corrugated structure 23 is disposed on the upper surface of the atomizing disk 21, which can enhance the efficiency of mechanical energy transferred to the alloy melt and improve the oxide film breaking effect on the surface of the alloy melt; taking the upper surface of the atomizing disk 21 as a reference plane, the reference plane is horizontal, and the height difference between the crests or troughs and the reference plane does not exceed 0.2 mm, preferably 0.1 mm; the corrugated structure 23 on the surface of the centrifugal disk 21 can be entirely composed of... Figure 2 The peaks shown in Figure f can all be... Figure 2 The troughs shown in Figure e, or a combination of peaks and troughs; the lower surface of centrifugal turntable 2 is smooth.

[0036] Before atomization begins, heater 4 moves to directly above centrifugal turntable 2 via guide rail 8 mechanism, and heats centrifugal turntable 2 by thermal radiation to eliminate impurities such as gases that may be adsorbed on the surface of centrifugal turntable 2, thereby improving the wettability between centrifugal turntable 2 and alloy melt.

[0037] In one embodiment, the heater 4 is disc-shaped, and its diameter is larger than the equivalent diameter of the atomizing disc 21. The thickness of the heater 4 is B, and the vertical distance between the end of the guide pipe 3 and the atomizing disc 21 is H, where B ≤ H / 3. This ensures that the centrifugal disc 2 is fully heated while reducing heating energy consumption. The thickness of the heater 4 does not exceed 1 / 3 of the vertical distance between the centrifugal disc 2 and the outlet of the guide pipe 3, preferably 1 / 4. The heater 4 is made of high-temperature refractory metal or graphite, which operates in a protective atmosphere (inert gas) and will not be damaged by oxidation. In this embodiment, graphite is preferred. The heater 4 is a resistance heating element, which provides strong temperature control and meets the spatial layout requirements of the equipment. The heating element is powered by an external power source through wires. After heating for a preset working time, the heating element moves away from directly above the centrifugal disc 2 via the guide rail 8 mechanism.

[0038] After heater 4 completes its heating operation and moves away from above centrifugal turntable 2, ultrasonic generator 5 reaches above centrifugal turntable 2 via guide rail 8. After atomization begins, ultrasonic generator 5 is turned on until the preset working time is reached and then stopped. During atomization, a high-definition camera collects information on the liquid film spreading on the surface of centrifugal turntable 2 according to a set sampling frequency and sends it back to computer 92. Computer 92 first determines whether the centrifugal turntable 2 body has disappeared. If the centrifugal turntable 2 body has disappeared, an alarm signal is immediately activated to alert the operator of a production malfunction. If the centrifugal turntable 2 is normal, the following process begins: Computer 92 determines the wetting condition of the centrifugal turntable 2 and the alloy melt, and whether atomization is successful. If atomization is successful, no command to turn on ultrasonic generator 5 is sent; if atomization is unsuccessful, a command to turn on ultrasonic generator 5 is sent, and the operator... The controller 91 turns on the ultrasonic generator 5 until the preset working time, and sends an alarm signal to the operator through the alarm 7. The working frequency and power of the ultrasonic generator 5 can ensure complete breaking of the oxide film of the alloy melt, but the interference should not be set too much in order to break the oxide film. This may cause the centrifugal turntable 2 to vibrate, which will have an adverse effect on the stability and safety of the centrifugal equipment, and will also increase energy consumption. The distance between the ultrasonic generator 5 and the upper surface of the centrifugal turntable 2 should not only avoid the high temperature damage of the ultrasonic generator 5 tool head caused by the high temperature of the centrifugal turntable 2 or the alloy melt, but also ensure that the ultrasonic waves can completely break the oxide film on the surface of the alloy melt. It is preferable to use a pulsed sound wave generator, as the intermittent ultrasonic field can better destroy the oxide film on the surface of the alloy melt.

[0039] Please refer to the above. Figure 3 The ultrasonic generator 5 is connected to the guide rail 8 via a bracket 51. During operation, it is positioned above the centrifugal turntable 2, ensuring that the centrifugal turntable 2 is within the ultrasonic field generated by the ultrasonic generator 5. The working head of the ultrasonic generator 5 can adopt a planar structure. Figure 4 (Figure a) can also be achieved using a parabolic concave structure ( Figure 4 Figure b), antenna structure ( Figure 4 Figure c), extended planar structure ( Figure 4 (See Figure d) to enhance the ultrasonic field and improve the breaking effect of ultrasound on the oxide film of the alloy melt. The working head surface size of the ultrasonic generator 5 is matched with the size of the centrifugal turntable 2 to ensure that the ultrasonic field completely covers the centrifugal turntable 2 while minimizing the total ultrasonic energy consumption.

[0040] In one embodiment, an obstacle avoidance hole is formed in the middle of the ultrasonic generator 5. When the ultrasonic generator 5 is located above the centrifugal turntable 2, the obstacle avoidance hole faces the guide pipe 3. There are multiple ultrasonic generators 5, which are arranged at intervals along the circumference of the centrifugal turntable 2. Each ultrasonic generator 5 is inclined and its working head faces the centrifugal turntable 2. Thus, when the ultrasonic generator 5 is working, it can avoid the jet formed by the alloy melt flowing out of the guide pipe 3 when the centrifugal turntable 2 is working, ensuring that the jet falls into the center of the centrifugal turntable 2.

[0041] In addition, such as Figure 5 As shown, this application also provides a centrifugal atomizer control method, which is applied to the centrifugal atomizer described above, and the centrifugal atomizer control method includes: S100, Move the heater above the centrifugal disc and heat the centrifugal disc; S200: When the centrifugal disc is cleaned, turn off the heater and move the heater away from above the centrifugal disc; The heater heats the centrifugal disc before atomization begins, eliminating harmful impurities such as adsorbed gases that reduce wettability on the surface of the centrifugal disc.

[0042] S300: Move the ultrasonic generator above the centrifugal turntable and start it to control the centrifugal turntable to begin atomization. The ultrasonic generator produces ultrasonic waves to form an ultrasonic field at the centrifugal turntable, which is used to break the oxide film on the surface of the alloy melt and enhance the wettability between the centrifugal turntable and the alloy melt to be atomized; it must be turned on in the initial stage of atomization.

[0043] S400, the detection component acquires images of the centrifuge disc in real time and determines whether the centrifuge disc is damaged; S500, if so, the alarm sends an alarm message.

[0044] The detection component uses a high-definition camera. Due to various issues such as severe temperature gradients, high temperatures, and the corrosiveness of the alloy melt to be atomized, the centrifugal turntable may break, disintegrate, or react with the alloy melt and disappear. In this case, the remaining part of the high-speed rotating centrifugal turntable and the dynamic balance capability of the drive motor often do not change significantly, and methods such as detecting vibration levels will become ineffective. The high-definition camera collects image information of the centrifugal turntable, compares it with the standard information in the database, and then issues an action command.

[0045] This application addresses the problem of insufficient wettability between the centrifugal disc and the alloy melt caused by adverse factors such as oxide film and adsorbed gases during the initial stage of atomization or during atomization by preheating the centrifugal disc with a heater or using an ultrasonic generator before atomization starts, and by enhancing the wettability between the alloy melt and the centrifugal disc with a pulsed ultrasonic field. Furthermore, it provides immediate alarm and stops feeding alloy melt to the centrifugal disc in extreme cases of disc breakage, preventing the alloy melt from falling directly onto the ultra-high-speed motor and causing damage, thus avoiding production losses.

[0046] In one embodiment, such as Figure 6 As shown, after the step of the detection component acquiring real-time images of the centrifuge disc and determining whether the centrifuge disc is damaged, the following steps are also included: S600, if the centrifugal turntable is not damaged within the preset working time T, then determine whether the alloy melt evenly covers the centrifugal turntable; S700, if not, then control the ultrasonic generator to work for a preset working time T, and execute the steps of the detection component to acquire the centrifugal disc image in real time and determine whether the centrifugal disc is damaged.

[0047] The images captured by the high-definition camera simultaneously include information on the integrity of the centrifugal turntable and information on the spread of the liquid film on the surface of the centrifugal turntable. When the liquid film of the alloy melt completely and uniformly covers the centrifugal turntable, the alloy melt is successfully atomized. When the liquid film of the alloy melt cannot completely and uniformly cover the centrifugal turntable, the ultrasonic generator is restarted to ensure that the alloy melt is successfully atomized.

[0048] In one embodiment, the theoretical time required for the alloy melt to travel from the center of the centrifugal disc to its exit from the centrifugal disc is defined as t, where T > 5t. After the alloy melt enters the center of the centrifugal disc, it flows radially outward along the centrifugal disc and finally reaches the edge of the centrifugal disc where it is atomized. The theoretical value of the time t required for this process is given below.

[0049] At a distance r from the center of the centrifugal disc, the velocity u of the alloy molten film along the height z direction conforms to the following relationship:

[0050] Near the surface of the centrifugal disc, the alloy melt exhibits no slippage relative to the disc surface; the boundary conditions are z=0, u=0. At a height h (h is the film thickness at this point) above the alloy melt film surface, the film is in contact with the inert gas above it; the boundary conditions are...

[0051] The velocity distribution of the liquid film at a distance r from the center of the centrifugal disc along its height z direction can be obtained as follows:

[0052] According to the law of conservation of mass, the flow rate q of the alloy melt from the liquid guide tube to the surface of the centrifugal disc can be expressed as:

[0053] Then the thickness h of the alloy melt film at a distance r from the center of the rotary disk can be obtained as follows:

[0054] Furthermore, the average radial velocity of the alloy molten film with a thickness of h at a distance r from the center of the rotary disk can be obtained. as follows

[0055] The time t taken for the alloy melt to travel from the center of the centrifugal disc to the surface of the centrifugal disc is:

[0056] In the above formula, r0 is the radius of the guide nozzle (the guide nozzle is connected at the outlet of the guide tube), r is the distance from the center of the centrifugal turntable, R is the radius of the centrifugal turntable, ω is the rotational speed of the centrifugal turntable, ρ and μ are the density and viscosity coefficient of the alloy melt, respectively, q is the flow rate of the alloy melt, and t is the theoretical time required for the alloy melt to fall into the center of the centrifugal turntable and leave the centrifugal turntable. The preset working time of the ultrasonic generator can be set to more than 5 times this theoretical time t.

[0057] The above description is merely a preferred embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the inventive concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A centrifugal atomizer, characterized in that, The centrifugal atomizer includes: Atomizing chamber, wherein the atomizing chamber is filled with inert gas; A centrifugal turntable, which is rotatably disposed within the atomization chamber; A guide tube passes through the top wall of the atomization chamber and is positioned directly opposite the center of the centrifugal disc. The guide tube is used to introduce the alloy melt. A heater is slidably connected to the inner wall of the atomization chamber. The heater can slide above the centrifugal disc to heat the centrifugal disc. Before the atomization operation begins, the centrifugal disc is preheated by the heater to remove the adsorbed gas on its surface and enhance the wettability between the alloy melt and the centrifugal disc. An ultrasonic generator is slidably connected to the inner wall of the atomization chamber. The ultrasonic generator can slide above the centrifugal disc to form an ultrasonic field at the centrifugal disc. During the atomization process, the ultrasonic generator forms an ultrasonic field at the centrifugal disc to destroy the oxide film of the alloy melt to be atomized, and the pulsed ultrasonic field enhances the wettability between the alloy melt and the centrifugal disc. The detection component is a high-definition camera. The viewfinder of the high-definition camera is positioned facing the centrifugal turntable. The high-definition camera is located outside the atomizing chamber. A transparent window is provided in the atomizing chamber corresponding to the position of the viewfinder of the high-definition camera. Alarm; The computer, the alarm, and the detection component are all electrically connected to the computer. The high-definition camera is used to acquire images of the centrifugal turntable in real time and input the images into the computer. The computer compares the images with the liquid film spreading image data on the surface of the centrifugal turntable when atomization is normal to determine whether atomization is proceeding smoothly. When the computer determines that the centrifugal turntable is damaged or the alloy melt coverage is uneven, it controls the alarm to send an alarm message.

2. The centrifugal atomizer as described in claim 1, characterized in that, The centrifugal turntable includes an atomizing disc and a support shaft connected together. The atomizing disc and the support shaft are coaxially arranged, and the support shaft is connected to the output shaft of the ultra-high-speed motor.

3. The centrifugal atomizer as described in claim 2, characterized in that, The atomizing disc is made of ceramic material or refractory hard metal material.

4. The centrifugal atomizer as described in claim 2, characterized in that, The surface of the atomizing disk is provided with a corrugated structure, and the size of the crest or trough of the corrugated structure does not exceed 0.2 mm.

5. The centrifugal atomizer as described in claim 2, characterized in that, The heater is disc-shaped, and the diameter of the heater is larger than the equivalent diameter of the atomizing disc; the thickness of the heater is B, and the vertical distance between the end of the guide tube and the atomizing disc is H, wherein B≤H / 3.

6. The centrifugal atomizer as described in claim 5, characterized in that, The heater is a resistance heating element.

7. The centrifugal atomizer according to any one of claims 1 to 6, characterized in that, A clearance hole is formed in the middle of the ultrasonic generator, and when the ultrasonic generator is located above the centrifugal disc, the clearance hole faces the guide tube; or, The number of ultrasonic generators is multiple, and the multiple ultrasonic generators are arranged at intervals along the circumference of the centrifugal turntable. Each ultrasonic generator is inclined and the working head of each ultrasonic generator is facing the centrifugal turntable.

8. A centrifugal atomizer control method, characterized in that, The centrifugal atomizer control method is applied to the centrifugal atomizer as described in any one of claims 1 to 7, and the centrifugal atomizer control method includes: Move the heater above the centrifugal disc and heat the centrifugal disc; Once the centrifuge disc has been cleaned, turn off the heater and move it away from above the centrifuge disc. Move the ultrasonic generator above the centrifugal turntable, control the centrifugal turntable to start atomization, turn on the ultrasonic generator after atomization starts and continue for a preset working time, then turn it off. The detection component acquires images of the centrifuge disc in real time and determines whether the centrifuge disc is damaged. If so, the alarm device sends an alarm message.

9. The centrifugal atomizer control method as described in claim 8, characterized in that, After the step of acquiring real-time images of the centrifuge disc and determining whether the centrifuge disc is damaged, the detection component further includes: If the centrifugal turntable is not damaged within the preset working time T, then it is determined whether the alloy melt evenly covers the centrifugal turntable. If not, the ultrasonic generator is controlled to work for a preset working time T, and the detection component is executed to acquire the centrifugal disc image in real time and determine whether the centrifugal disc is damaged.

10. The centrifugal atomizer control method as described in claim 9, characterized in that, The theoretical time required for the alloy melt to fall from the center of the centrifugal turntable to leave the centrifugal turntable is defined as t, where T > 5t.

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