Modular adaptive crystallizer for large size ingots

Abstract

The present application belongs to the technical field of non-ferrous metal casting, and discloses a modular adaptive crystallizer for large-size ingot casting, which solves the problems of fixed cooling intensity and poor adaptability of the existing crystallizer. The present application comprises a plurality of independent cooling modules, an adaptive control system and an online monitoring unit. The independent cooling modules are arranged in the crystallizer along the axial direction, and each independent cooling module is internally provided with a micro-channel cooling plate. The adaptive control system comprises a programmable logic controller, an electric regulating valve and a cooling water distributor, and the electric regulating valve is arranged on the water inlet pipeline of each independent cooling module. The online monitoring unit is used for real-time acquisition of temperature field data and feedback to the adaptive control system, and the programmable logic controller of the adaptive control system dynamically adjusts the cooling water flow of each independent cooling module according to the preset temperature field model. The present application significantly improves the cooling uniformity of the ingot, and improves the production adaptability through the modular structure design.

Description

Technical Field

[0001] This invention belongs to the field of non-ferrous metal casting technology, and particularly relates to a modular adaptive crystallizer for large-size ingots. Background Technology

[0002] High aspect ratio 7-series aluminum alloy ingots (thickness ≥ 500 mm, width ≥ 2000 mm) are the base material for ultra-wide plates used in aerospace. Their casting quality directly determines the pass rate of subsequent plate flaw detection and overall performance. In the semi-continuous casting process, the crystallizer is a key temperature control component, and its cooling uniformity and adaptability directly affect the solidification structure, thermal stress distribution, and crack susceptibility of the ingot.

[0003] The existing crystallizers have the following technical problems: (1) Fixed cooling intensity and poor adaptability: Traditional crystallizers adopt an integral water jacket structure, and the cooling water flow rate and distribution are fixed. They cannot be dynamically adjusted according to the ingot specifications (thickness and width changes) and casting stage, resulting in overcooling at the edges and insufficient feeding in the core, which leads to hot cracks and segregation. (2) Excessively thick quenching layer and stress concentration: The initial cooling rate is too fast (>1000℃ / s), and an excessively thick quenching layer (>3mm) is formed on the surface of the ingot. The difference between the core structure and the core structure is large, which causes huge thermal stress and increases the risk of cracking. (3) High maintenance cost and low flexibility: Once the integral crystallizer is worn or blocked, it needs to be replaced as a whole. The replacement cycle is long and the cost is high. It cannot adapt to the flexible production needs of multiple specifications and small batches. (4) Insufficient temperature field control capability: There is a lack of real-time monitoring and closed-loop control of the temperature field during the solidification process of the ingot, which makes it difficult to suppress metallurgical defects such as "A" type segregation and central porosity.

[0004] Therefore, there is an urgent need to develop a crystallizer that can adaptively adjust cooling intensity, improve cooling uniformity, reduce the thickness of the quench layer, and has a modular structure. Summary of the Invention

[0005] The purpose of this invention is to provide a modular adaptive crystallizer for large-size ingots, which effectively solves the problems of fixed cooling intensity and poor adaptability of existing crystallizers.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a modular adaptive crystallizer for large-size (thickness ≥ 500 mm, width ≥ 2000 mm) ingots, comprising multiple independent cooling modules, an adaptive control system, and an online monitoring unit; the independent cooling modules are arranged axially within the crystallizer, and each independent cooling module is equipped with a microchannel cooling plate; the adaptive control system includes a programmable logic controller, an electric regulating valve, and a cooling water distributor, the electric regulating valve being located on the inlet pipe of each independent cooling module, and the electric regulating valve being used to control the cooling water flow rate and pressure; the online monitoring unit includes thermocouples, a temperature measuring instrument, and cooling water flow and pressure sensors, the online monitoring unit being used to collect temperature field data in real time and feed it back to the adaptive control system, and the programmable logic controller of the adaptive control system dynamically adjusts the cooling water flow rate of each independent cooling module according to a preset temperature field model.

[0007] Furthermore, the adaptive control system adopts a zoned control mode according to the ingot specifications and casting stage: First, in the initial casting stage: the cooling water flow rate of the independent cooling module located in the central area of ​​the long side of the crystallizer is adjusted to 30-50% of the rated value, and the cooling water flow rate of the independent cooling modules located at both ends of the long side of the crystallizer and the independent cooling module located on the short side of the crystallizer is adjusted to 10-30% of the rated value.

[0008] Secondly, during the stable casting stage: the cooling water flow rate of the independent cooling module located in the central area of ​​the long side of the crystallizer is adjusted to 80-100% of the rated value, and the cooling water flow rate of the independent cooling modules located at both ends of the long side of the crystallizer and the independent cooling module located on the short side of the crystallizer is adjusted to 50-70% of the rated value.

[0009] Finally, in the final stage: the cooling water flow rate of all independent cooling modules is reduced linearly or stepwise to 0-20% of the rated value within 30-60 seconds until casting completely stops.

[0010] Furthermore, there are multiple thermocouples distributed at different locations within the crystallizer; the thermocouples are embedded in the crystallizer wall via blind holes, 5-10 mm from the hot working surface of the crystallizer.

[0011] The thermometer is used to detect the surface temperature of the ingot, and the thermometer is aimed at the surface of the ingot 50-150mm below the outlet of the crystallizer.

[0012] The cooling water flow and pressure sensors are used to provide execution feedback and safety monitoring for the adaptive control system.

[0013] Furthermore, the frame of the crystallizer is rectangular. For ingots with a thickness of 500-800mm and a width of 2000-2700mm, 8-12 independent cooling modules are set along the long side of the crystallizer, and 2-4 independent cooling modules are set along the short side of the crystallizer.

[0014] Furthermore, the cross-sectional dimensions of the microchannel cooling plate are 0.5-2.0 mm, and the channel spacing is 1-5 mm.

[0015] Furthermore, the surface of the microchannel cooling plate is coated with a high thermal conductivity coating with a thermal conductivity of ≥200W / (m·K) and is provided with a porous ceramic layer.

[0016] Furthermore, the number of thermocouples is not less than 24.

[0017] Furthermore, an alternating electromagnetic field generator is installed around the frame of the crystallizer.

[0018] Furthermore, the central region of the crystallizer is equipped with an array of ultrasonic probes for breaking dendrites and promoting gas expulsion; the frequency of the ultrasonic probes is 20-40kHz, and the power density of the probe radiation surface is 0.5-2.0W / cm². 2 .

[0019] Furthermore, the temperature field model includes constraints: the width of the mushy region ≤ 80 mm, and the peak thermal stress ≤ 40 MPa.

[0020] Compared with the prior art, the beneficial technical effects of the present invention are: (1) Significantly improved cooling uniformity: Through modular independent control, this invention reduces the circumferential temperature difference of the ingot from 50-80℃ in traditional crystallizers to less than 15℃, making the solidification isotherm smoother and reducing thermal stress by 30-50%.

[0021] (2) Controllable chilling layer and reduced crack rate: The present invention reduces the thickness of the chilling layer from 3-5mm to less than 1.5mm through the synergistic effect of the microchannel cooling plate and the porous ceramic layer, and reduces the surface crack rate of the ingot from 8-12% to less than 2%.

[0022] (3) Flexible production adaptability: The modular structure of the present invention can quickly replace or increase or decrease the number of independent cooling modules according to the ingot specifications, shortening the production changeover time from 2-3 days to 4-6 hours, meeting the production needs of multi-variety, small-batch aviation aluminum alloys.

[0023] (4) Extended service life and reduced maintenance costs: After a single independent cooling module is worn or blocked, the present invention only needs to replace the faulty module, without replacing the entire crystallizer, thus reducing maintenance costs by more than 60%.

[0024] (5) Improvement of metallurgical quality: This invention combines electromagnetic / ultrasonic auxiliary functions to reduce the macrosegregation index of ingots to 0.95-1.05 and increase the flaw detection pass rate (AA grade) from 85% to over 95%. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the modular adaptive crystallizer of the present invention.

[0026] Figure 2 This is a logic block diagram of the adaptive control system of the present invention.

[0027] Figure 3 This is a comparison chart of the macrosegregation index of the ingots in Test Example 1 and Comparative Example 1.

[0028] Figure 4 This is a comparison diagram of the solidification temperature field distribution of the ingot in Test Example 1 and Comparative Example 1. Detailed Implementation

[0029] Example 1: A modular adaptive crystallizer for large-size (thickness ≥ 500 mm, width ≥ 2000 mm) ingots, including multiple independent cooling modules, an adaptive control system and an online monitoring unit.

[0030] In this embodiment, as Figure 1 As shown, the modular adaptive crystallizer frame is a rectangular frame structure with multiple mounting slots along the axial direction inside. Each mounting slot can be detachably installed with an independent cooling module. The independent cooling modules can be combined into different numbers of module arrays according to the ingot specifications (thickness, width). For example, for ingots with a thickness of 500-800mm and a width of 2000-2700mm, 8-12 independent cooling modules are set along the long side of the crystallizer, and 2-4 independent cooling modules are set along the short side of the crystallizer.

[0031] Each independent cooling module includes: a shell, a microchannel cooling plate, a water collection chamber, and independent inlet / outlet water piping. The microchannel cooling plate is located within the independent cooling module, with a cross-sectional dimension of 0.5-2.0 mm and a channel spacing of 1-5 mm. The surface of the microchannel cooling plate is coated with a high thermal conductivity coating with a thermal conductivity ≥200 W / (m·K) and features a porous ceramic layer to reduce the initial cooling rate. The microchannel structure increases the heat exchange area between the cooling water and the crystallizer wall by 30-50%, while the porous ceramic layer reduces the initial cooling rate from >1000℃ / s to 300-600℃ / s, effectively controlling the quench layer thickness (≤1.5 mm).

[0032] The heat from the solidifying aluminum alloy molten material / ingot is transferred outward through independent cooling modules. Microchannel cooling plates are placed close to the molten aluminum alloy / ingot, directly absorbing the ingot's heat for efficient heat exchange. A water collection chamber collects the cooling water flowing from each microchannel cooling plate and directs it to the return water pipe, thus achieving uniform water flow, reducing pressure fluctuations, and ensuring a roughly uniform flow rate for each microchannel cooling plate. The inlet connects to an external cooling water source, and the return outlet discharges the heat-exchanged water from the collection chamber to the external cooling system. During the cooling process, cooling water enters through the inlet, first flowing through the microchannel cooling plates to absorb the ingot's heat, then converging into the collection chamber, and finally exiting through the return outlet, achieving efficient heat exchange.

[0033] like Figure 2 As shown, the adaptive control system includes a programmable logic controller (PLC), an electric regulating valve, and a cooling water distributor. The electric regulating valve is located on the inlet pipe of each independent cooling module and is used to control the cooling water flow rate (0-30L / min·independent cooling module) and pressure (0.2-1.0MPa).

[0034] Based on the ingot specifications and casting stage, the adaptive control system adopts a zoned control mode: ① During the initial casting stage (i.e., within 60 seconds after casting begins): the cooling water flow rate of the independent cooling module located in the central area of ​​the long side of the crystallizer (i.e., the wide side center module) is adjusted to 30-50% of the rated value, and the cooling water flow rate of the independent cooling modules located at both ends of the long side of the crystallizer and the independent cooling modules located on the short side of the crystallizer (i.e., the side modules) is adjusted to 10-30% of the rated value to reduce the stress of the chilled layer.

[0035] ② During the stable casting stage: the cooling water flow rate of the wide-side center module is increased to 80-100% of the rated value, and the cooling water flow rate of the edge module is increased to 50-70% of the rated value, forming a gentle temperature gradient.

[0036] ③ In the final stage: The cooling water flow rate of all independent cooling modules is gradually reduced to prevent cracks from forming at the tail of the ingot.

[0037] The final stage refers to the last 60-120 seconds before casting ends, or when the ingot tail is 200-400mm from the crystallizer outlet. During this final stage, the programmable logic controller (PLC) linearly or stepwise reduces the cooling water flow of all independent cooling modules to 0-20% of the rated value within 30-60 seconds, until casting completely stops. By gradually reducing the cooling intensity, transverse cracks are avoided at the ingot tail due to obstructed shrinkage caused by rapid cooling.

[0038] The online monitoring unit includes multiple thermocouples, an infrared thermometer, and cooling water flow and pressure sensors. The online monitoring unit is used to collect temperature field data in real time and feed it back to the adaptive control system. The programmable logic controller of the adaptive control system dynamically adjusts the cooling water flow of each independent cooling module according to the preset temperature field model to achieve closed-loop control. The temperature field model includes the following constraints: the width of the mushy region is ≤80mm and the peak thermal stress is ≤40Mpa. (1) There are multiple thermocouples (no less than 24), and the multiple thermocouples are distributed in different positions of the crystallizer frame; specifically, the thermocouples are buried in the crystallizer wall through blind holes, 5-10mm away from the hot working surface of the crystallizer. (2) The infrared thermometer is used to detect the surface temperature of the ingot. The infrared thermometer is aimed at the surface of the ingot 50-150mm below the crystallizer outlet. (3) Cooling water flow and pressure sensors are used to provide execution feedback and safety monitoring for the adaptive control system, specifically including: ① Precise closed-loop control: After the PLC calculates the target flow value required for each independent cooling module according to the temperature field model, it adjusts the opening through the electric regulating valve; the cooling water flow and pressure sensors monitor the actual water flow and water pressure in real time and feed them back to the PLC to form a closed-loop PID control, ensuring that the actual flow is consistent with the set value (the error is usually controlled within ±2%). ② Fault diagnosis and safety interlock: Blockage detection: When the actual flow of an independent cooling module is much lower than the set value and the pressure rises abnormally, the system determines that the microchannel of the module is blocked, automatically alarms and adjusts the flow compensation of adjacent modules to prevent local cooling failure; Leakage detection: If the flow and pressure do not match (such as the flow increases but the pressure drops suddenly), it indicates pipeline leakage. The system immediately shuts down the module and starts the emergency casting program; Water pump status monitoring: When the total inlet water pressure is lower than the lower limit, the system determines that the water supply is faulty and triggers the casting machine to decelerate or stop, so as to avoid the ingot being scrapped due to water interruption. ③ Process Data Recording and Analysis: Sensor data, along with temperature, casting speed, and other parameters, are recorded synchronously for subsequent process optimization. For example, by analyzing the relationship between flow rate and ingot microstructure, the "rated value" parameter in the zone control strategy can be iteratively improved. In summary, cooling water flow rate and pressure sensors are key feedback links connecting "control decision-making" and "actual execution." Without them, adaptive control can only be open-loop blind adjustment, failing to guarantee accuracy and reliability.

[0039] In other embodiments, the modular adaptive crystallizer also features electromagnetic stirring. For example, an alternating electromagnetic field generator is placed around the crystallizer frame, working in conjunction with an independent cooling module to further refine the grains and reduce segregation. The alternating electromagnetic field generator is used to generate electromagnetic stirring during ingot solidification, driving forced convection of the melt through Lorentz force to refine the grain structure, reduce macroscopic segregation, and promote gas expulsion. This electromagnetic stirring function, in conjunction with the zoned cooling module, reduces the initial cooling intensity to control thermal stress while refining the structure and improving uniformity through convection feeding, thereby achieving both crack-free and fine-grained structures.

[0040] In other embodiments, the modular adaptive crystallizer also features ultrasonic assistance, for example, by arranging an array of ultrasonic probes in the central region of the crystallizer to generate a stable cavitation effect in the melt, thereby breaking up dendrites and promoting gas expulsion. The ultrasonic probes have a frequency of 20-40 kHz and a power density of 0.5-2.0 W / cm². 2 .

[0041] The present invention will be further described in detail below through specific test examples and comparative examples.

[0042] Test Example 1: Casting of 7050 aluminum alloy flat ingots with high aspect ratio.

[0043] The ingot specifications for this test case are: thickness 520mm, width 2300mm, and length 6000mm.

[0044] The modular adaptive crystallizer used in this test case has the following configuration for its independent cooling modules: 10 independent cooling modules along the wide side and 3 independent cooling modules along the narrow side. The modular adaptive crystallizer used in this test case also features electromagnetic stirring.

[0045] The casting process parameters for this test case are: casting temperature 680-690℃, casting speed 35-45mm / min, and cooling water temperature 25±2℃.

[0046] The control process of the modular adaptive crystallizer used in this test example is as follows: ① Initial stage (within 60 seconds after casting begins): flow rate of 8 L / min for the wide-edge center module and 4 L / min for the edge modules. The porous ceramic layer controls the initial cooling rate at 450℃ / s. ② Stabilization stage: flow rate of 25 L / min for the wide-edge center module and 15 L / min for the edge modules. The width of the paste-like zone is stabilized at 60-75 mm through thermocouple feedback adjustment. ③ Electromagnetic field parameters: alternating magnetic field frequency 15 Hz, magnetic flux density 0.3 T.

[0047] The ingots cast using the modular adaptive crystallizer in this test example have the following characteristics: chilled layer thickness of 1.2 mm; maximum circumferential temperature difference of 12℃; no hot cracks; macroscopic segregation index of 1.00-1.03; and flaw detection pass rate (AA grade) of 96.5%.

[0048] Test Example 2: Casting of 7075 aluminum alloy ultra-wide flat ingots.

[0049] The ingot specifications for this test example are: thickness 500mm, width 2520mm, and length 7000mm.

[0050] The modular adaptive crystallizer used in this test case has the following configuration for its independent cooling modules: 12 independent cooling modules along the wide side and 4 independent cooling modules along the narrow side. The modular adaptive crystallizer used in this test case also features ultrasonic assistance.

[0051] The casting process parameters for this test case are: casting temperature 670-680℃, casting speed 30-40mm / min, and cooling water temperature 25±2℃.

[0052] The control process of the modular adaptive crystallizer used in this test example is as follows: ① Initial stage (within 60 seconds after casting begins): flow rate of 6 L / min for the wide-side center module and 3 L / min for the edge modules. ② Stabilization stage: flow rate of 22 L / min for the wide-side center module and 12 L / min for the edge modules. ③ Ultrasonic assistance: frequency 28 kHz, power density 1.2 W / cm².

[0053] The ingots cast using the modular adaptive crystallizer in this test example have the following characteristics: chilled layer thickness of 1.0 mm; maximum circumferential temperature difference of 10 °C; microporosity grade of 1 (ASTM E155); and flaw detection pass rate (AA grade) of 97.2%.

[0054] Comparative Example 1: This comparative example uses a traditional integral crystallizer to cast 7050 aluminum alloy flat ingots of the same specifications as Test Example 1. The casting process parameters are the same as those of Test Example 1. The ingots cast in this comparative example have the following characteristics: chilled layer thickness of 3.8 mm; maximum circumferential temperature difference of 68℃; surface crack rate of 11.2%; and flaw detection pass rate (AA grade) of 84.5%.

[0055] Figure 3 The comparison of macroscopic segregation indices is shown between ingots cast using the modular adaptive crystallizer of this invention (Test Example 1) and ingots cast using a conventional crystallizer (Comparative Example 1). Figure 3 It can be seen that the macrosegregation index of the ingot in this invention is reduced to 1.00-1.03.

[0056] like Figure 4As shown, the ingot cast using the modular adaptive crystallizer of the present invention (Test Example 1) has the following advantages compared with the ingot cast using a conventional crystallizer (Comparative Example 1): (1) Significantly improved temperature field uniformity: This invention makes the temperature distribution of the ingot cross section more gradual, with a smooth transition from the low temperature at the edge to the high temperature at the center. In contrast, traditional crystallizers experience overcooling (a sharp drop in temperature) at the edge, resulting in a temperature difference as high as 68°C. This invention reduces the temperature difference to 12°C, indicating that the cooling intensity has been effectively controlled by zone.

[0057] (2) Thermal stress is significantly reduced, and the risk of cracking is reduced: Temperature gradient is the main source of thermal stress. This invention reduces the temperature difference by about 5.6 times (68℃ → 12℃), which means that the peak thermal stress during solidification is significantly reduced, thereby reducing the generation of hot cracks and cold cracks.

[0058] (3) Controllable chilling layer and improved microstructure uniformity: The temperature at the edge of the traditional crystallizer is too low (the curve dips significantly to the left), which will form an excessively thick chilling layer (>3mm), resulting in a large difference between the surface and the interior microstructure. In contrast, the temperature at the edge of the present invention is relatively high, and the thickness of the chilling layer can be controlled within 1.5mm, which is beneficial to the uniformity of subsequent rolling and the final plate properties.

[0059] (4) Provide verification basis for adaptive control: Figure 4 The gentle trend of the solid blue line directly proves the effectiveness of the "zoning control strategy" proposed in this invention (reducing the flow at the edges in the initial stage and forming a gentle gradient in the stable stage), and also verifies that the temperature field model with "pasty region width ≤ 80mm" as its core can be actually implemented.

[0060] In summary, the advantages of the modular adaptive crystallizer of this invention in controlling the solidification temperature field of ingots are clearly demonstrated: by independently adjusting the flow rate of each independent cooling module, an approximately linear cooling from the edge to the center is achieved, greatly reducing the temperature difference, thus providing key process assurance for the production of high aspect ratio, crack-free, and uniformly structured 7-series aluminum alloy ingots for aerospace applications.

[0061] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A modular adaptive crystallizer for large-size ingots, characterized in that, Includes multiple independent cooling modules, an adaptive control system, and an online monitoring unit; The independent cooling modules are arranged axially inside the crystallizer, and each independent cooling module is equipped with a microchannel cooling plate. The adaptive control system includes a programmable logic controller, an electric regulating valve, and a cooling water distributor. The electric regulating valve is located on the inlet pipe of each independent cooling module and is used to control the cooling water flow rate and pressure. The online monitoring unit includes thermocouples, temperature measuring instruments, and cooling water flow and pressure sensors. The online monitoring unit is used to collect temperature field data in real time and feed it back to the adaptive control system. The programmable logic controller of the adaptive control system dynamically adjusts the cooling water flow of each independent cooling module according to the preset temperature field model.

2. The modular adaptive crystallizer for large-size ingots according to claim 1, characterized in that, The adaptive control system adopts a zoned control mode based on the ingot specifications and casting stage: First, during the initial casting stage: the cooling water flow rate of the independent cooling module located in the central area of ​​the long side of the crystallizer is adjusted to 30-50% of the rated value, and the cooling water flow rate of the independent cooling modules located at both ends of the long side of the crystallizer and the independent cooling module located on the short side of the crystallizer is adjusted to 10-30% of the rated value; Secondly, during the stable casting stage: the cooling water flow rate of the independent cooling module located in the central area of ​​the long side of the crystallizer is adjusted to 80-100% of the rated value, and the cooling water flow rate of the independent cooling modules located at both ends of the long side of the crystallizer and the independent cooling module located on the short side of the crystallizer is adjusted to 50-70% of the rated value; Finally, in the final stage: the cooling water flow rate of all independent cooling modules is reduced linearly or stepwise to 0-20% of the rated value within 30-60 seconds until casting completely stops.

3. The modular adaptive crystallizer for large-size ingots according to claim 1, characterized in that, There are multiple thermocouples, which are distributed in different positions in the crystallizer; the thermocouples are embedded in the crystallizer wall through blind holes, 5-10 mm away from the hot working surface of the crystallizer. The thermometer is used to detect the surface temperature of the ingot, and the thermometer is aimed at the surface of the ingot 50-150mm below the outlet of the crystallizer. The cooling water flow and pressure sensors are used to provide execution feedback and safety monitoring for the adaptive control system.

4. The modular adaptive crystallizer for large-size ingots according to claim 2, characterized in that, The frame of the crystallizer is rectangular. For ingots with a thickness of 500-800mm and a width of 2000-2700mm, 8-12 independent cooling modules are set along the long side of the crystallizer, and 2-4 independent cooling modules are set along the short side of the crystallizer.

5. The modular adaptive crystallizer for large-size ingots according to claim 1, characterized in that, The cross-sectional dimensions of the microchannel cooling plate are 0.5-2.0 mm, and the channel spacing is 1-5 mm.

6. The modular adaptive crystallizer for large-size ingots according to claim 5, characterized in that, The surface of the microchannel cooling plate is coated with a high thermal conductivity coating with a thermal conductivity of ≥200W / (m·K) and has a porous ceramic layer.

7. The modular adaptive crystallizer for large-size ingots according to claim 3, characterized in that, The number of thermocouples shall not be less than 24.

8. The modular adaptive crystallizer for large-size ingots according to any one of claims 1-7, characterized in that, An alternating electromagnetic field generator is installed around the frame of the crystallizer.

9. The modular adaptive crystallizer for large-size ingots according to claim 8, characterized in that, An array of ultrasonic probes is installed in the central area of ​​the crystallizer to break dendrites and promote gas discharge; The ultrasonic probe operates at a frequency of 20-40 kHz, and the power density of its radiating surface is 0.5-2.0 W / cm². 2 .

10. The modular adaptive crystallizer for large-size ingots according to claim 1, characterized in that, The temperature field model includes the following constraints: width of the mushy region ≤ 80 mm, peak thermal stress ≤ 40 MPa.

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