A temperature control system for growing noble metal filaments using the micro-pull-down method

Abstract

This invention relates to the field of precious metal filament fabrication technology, specifically to a temperature control system for growing precious metal filaments using a micro-pull-down method. The system includes a crucible and a quartz tube. An induction coil is surrounded by the quartz tube. A first thermocouple is installed inside the crucible, and a second thermocouple is installed at the bottom inner side of the crucible. A magnetic conductor is installed outside the induction coil. A cooling assembly is fixedly connected to the bottom of a second flange. A crystallizer is located at the center of the crucible's bottom, and a seed crystal guide is installed inside the crucible. The system also includes a control module for setting initial parameters required for precious metal filament fabrication, adjusting the output power of the induction coil, and controlling the operating speed of the collection assembly. This invention enables controllable solidification of fluids, stabilizes the solidification interface position, directly grows precious metal filaments from the melt, and precisely controls the microstructure and properties, ultimately achieving short-process, low-cost manufacturing.

Description

Technical Field

[0001] This invention relates to the field of precious metal filament fabrication technology, specifically to a temperature control system for growing precious metal filaments using a micro-pull-down method. Background Technology

[0002] Precious metals, due to their unique physical and chemical properties (high melting point, oxidation resistance, corrosion resistance, and stable physicochemical properties), are widely used in defense industries and key sectors of the national economy, such as aerospace, medical and health, weaponry, and energy and chemical industries. Among these, precious metal wires, with their high melting point, high oxidation resistance, and catalytic properties, have become crucial core components with irreplaceable advantages. Examples include PtIr alloys for reliable ignition in aero-engines, ultra-high temperature Ir-Rh thermocouples for oxidizing environments above 2100℃, Pt-W wires for precision potentiometer windings, Pd3Fe alloy coils for contact combustion and thermal linear gas-sensitive elements, Au-Pd-Fe high-resistance alloys, and AuCuPtAg and PdIr electrical contact brush materials.

[0003] Manufacturing precious metal wire using traditional techniques is extremely difficult, typically involving various processes such as induction / arc melting → casting → repeated heat treatment → multiple drawing / deformation stages. However, this method suffers from the following common problems: (1) low yield, complex processes, and long manufacturing period. Especially in the deformation stage after melting, the precious metal block material needs to undergo multiple deformation and annealing stages; (2) high processing difficulty and forming difficulty. Some platinum group metals and alloys have the characteristics of high melting point, high brittleness, and low plasticity; (3) high manufacturing cost. Forming wire from the initial large ingot increases manufacturing costs, especially for precious metals, where the processing loss of the starting material has a significant impact on the product price; (4) difficulty in controlling the microstructure-property stability. Due to the complex influence of the original microstructure and the hot processing process on the final microstructure of the precious metal wire, the phase structure is prone to problems such as uneven characteristics and unstable properties.

[0004] Currently, the plastic processing methods for drawing precious metal microwires are constrained by the characteristics of cold working and deformation methods, making it difficult to produce high-quality metal wires. With the development of technology, the micro-drawing method has emerged, which can effectively solve the drawbacks of the above methods. Micro-drawing technology is a molten crystal growth technique based on the continuous solidification of the melt. The precious metal melt in the crucible flows downward through a thin tube channel at the bottom of the crucible. Simultaneously, under the traction of the seed crystal and the effects of gravity and capillary action, the melt can be transported to the liquid / solid growth interface formed at the bottom of the crucible. Its core point is the precise control of the temperature field. A significant advantage of using the drawing method to grow precious metal wires is the reduction of defects such as shrinkage cavities and porosity, improving the overall quality. Furthermore, due to gravity, air bubbles inside the melt move to the top of the melt, away from the growth interface, greatly reducing the possibility of air bubbles entering the crystal.

[0005] Domestic research on micro-drawing technology for precious metal materials is weak. Currently, there are no technologies or systems available for producing small-diameter precious metal wires using this method, and no related reports exist. Many control principles need to be mastered, and a series of technical problems remain to be solved. The main difficulty lies in the precise control of the growth interface position. While the position of the growth (liquid / solid) interface is usually fixed in a stable state, it is influenced by various factors such as wettability with the melt, temperature gradient, and the shape and length of the molten zone, making it difficult to achieve precisely. To address this, this invention proposes an innovative temperature control system for growing fine precious metal wires using the micro-drawing method. This system enables controllable solidification of the fluid, thereby stabilizing the solidification interface position and directly growing precious metal wires from the melt. It allows for precise control of the microstructure and properties, ultimately achieving short-process, low-cost manufacturing. Summary of the Invention

[0006] To address the aforementioned issues, this invention provides a temperature control system for growing precious metal filaments using the micro-pull-down method. This system can be used for growing small-diameter precious metal filaments using the micro-pull-down method, and features a simple process, high production efficiency, strong applicability, and high-quality filaments.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows: A temperature control system for growing precious metal filaments using a micro-pull-down method includes a crucible and a quartz tube. A first flange and a second flange are fixedly connected to the top and bottom of the quartz tube, respectively. The crucible is disposed inside the quartz tube. An induction coil for heating and melting precious metals is surrounded around the outside of the quartz tube. A first thermocouple for detecting the temperature of the melt formed by the melting of precious metals is disposed inside the crucible. A second thermocouple for measuring the temperature near the meniscus between the precious metal melt and the solid is disposed at the bottom of the inner side of the crucible. A magnetic conductor is disposed outside the induction coil. A cooling assembly is fixedly connected to the bottom of the second flange. A crystallizer communicating with the inside of the crucible is disposed at the center of the bottom of the crucible. The bottom end of the crystallizer passes through the second flange and the cooling assembly in sequence. A seed crystal guide is disposed inside the crucible. The bottom end of the seed crystal guide passes through the crucible and the crystallizer in sequence and extends to the outside, and the seed crystal guide is slidably connected to the crystallizer and the crucible. The system also includes a collection assembly for traction and collection of metal filaments.

[0008] It also includes a control module, in which the first and second temperature-measuring thermocouples, the induction coil, the cooling assembly, and the collection assembly are all connected to the control module via signals. This module is used to set the initial parameters required for the production of precious metal wire based on the physical properties of the precious metal; to adjust the output power of the induction coil based on the monitoring data from the first and second temperature-measuring thermocouples; to control the operating speed of the collection assembly based on the actual production status of the precious metal wire; and to display the detection data from the first and second temperature-measuring thermocouples, while also being able to set a target temperature at any point for temperature adjustment.

[0009] Furthermore, the central axes of the first flange, the second flange, the quartz tube, the induction coil, the crucible, the crystallizer, the cooling assembly, and the seed crystal guide are all on the same vertical straight line.

[0010] Furthermore, the crystallizer is provided with a first through hole that communicates with the crucible. The diameter of the first through hole at the end near the crucible is equal to the diameter of the precious metal filament to be grown, and the diameter of the first through hole at the end away from the crucible is greater than the diameter of the precious metal filament. The first through hole is shaped like a frustum.

[0011] Furthermore, the cooling assembly includes a circulating water cooling unit that is connected to the control module via signals, and the circulating water cooling unit is made of copper.

[0012] Furthermore, the collection components include a clamping roller and a winding machine for pulling precious metal wires. The clamping roller and the winding machine are set on the collection path of the finished precious metal wires, and both the clamping roller and the winding machine are signal connected to the control module.

[0013] Furthermore, a second through hole is opened at the bottom of the crucible, which is connected to the crystallization tube. The diameter of the second through hole is equal to the diameter of the precious metal filament to be grown.

[0014] Furthermore, the control module is also used to control the speed of the winding machine and the clamping rollers to grow the filament according to preset pull-down speed parameters.

[0015] Furthermore, the initial parameters include the temperature of the circulating water cooling unit and the melting temperature of the metal material.

[0016] Furthermore, the bottom of the circulating water cooling unit is equipped with a ventilation component for introducing inert gas into the bottom of the crystallization tube. The ventilation component includes a gas pipe and a gas pump connected to the gas pipe.

[0017] Furthermore, it also includes a feedback module for detecting the working status of the first and second temperature measuring thermocouples. When the deviation between the real-time temperature data change curve detected by the first or second temperature measuring thermocouple and the normal change curve is greater than a preset deviation, an alarm signal is generated and transmitted to the control module, which then displays the corresponding alarm image.

[0018] The technical principle of the above scheme is as follows: The metal raw material in the crucible is heated by an induction coil, and the temperature of the melt inside the crucible is detected by a first thermocouple. When the internal temperature is higher than the melting point of the precious metal, the seed crystal guide rod is moved down to contact the bottom of the crucible, forming a meniscus at the bottom. A second thermocouple measures the temperature near the meniscus, thereby controlling the position of the solid-liquid interface. By observing the temperature of the second thermocouple displayed on the control module, the induction coil is controlled to adjust the temperature, making the temperature near the meniscus slightly lower than the melt temperature. The melt temperature is then finely adjusted. When the melt wets the entire bottom of the crucible and the melt side surface does not bulge outwards, the filament is grown according to the set pull-down rate parameters. A circulating water cooling unit cools the metal filament inside the crystallization tube, while an inert gas is introduced to reduce the possibility of oxidation. Throughout the process, the usage of the first and second thermocouples is monitored in real time by a feedback module.

[0019] The above approach has the following beneficial effects:

[0020] 1. Compared with existing technologies, this solution significantly reduces raw material loss in traditional drawing methods. The device structure is relatively simple, and the growth rate of the filament can be changed by adjusting the pulling speed of the clamping rollers, thus greatly improving production efficiency. In this invention, when the height of the induction coil is fixed, the crucible position with optimal heating capacity can be obtained for a specific volume of material in the crucible. This invention applies a magnetic conductor outside the induction coil to achieve a magnetic focusing effect, which can greatly reduce energy loss. Thermocouples are set at the top and bottom inside the crucible to achieve precise monitoring and control of the melt temperature and the temperature near the meniscus, thereby fixing the position of the solid-liquid interface and ensuring stable filament growth. This invention sets a circulating water cooling unit outside the crystallizer. By adjusting the water temperature of the circulating water cooling unit, the cooling rate of the filament can be changed, which is beneficial to obtaining a fine-grained structure. The internal through-hole of the crystallizer adopts a frustum structure that is narrow at the top and wide at the bottom, which effectively reduces the friction between the inner wall and the filament, prevents filament breakage, and improves the surface quality of the filament.

[0021] 2. In this solution, the control module can not only set initial parameters based on the physical properties of precious metals, such as the temperature of the cooling components and the melting temperature of the metal materials, but also adjust the output power of the induction coil based on real-time monitoring data and control the operating speed of the collection components. In addition, the control module can display the detection data of the thermocouples and allow users to set the target temperature at any point for temperature adjustment, which increases the flexibility and operability of the system, thereby accurately controlling the temperature during the production of precious metal wires and ensuring its cost-effectiveness.

[0022] 3. In this solution, the ventilation component introduces inert gas into the bottom of the crystallization tube, which can further protect the filament from adverse effects such as oxidation during growth and cooling, and improve the purity and performance of the filament.

[0023] 4. In this solution, the feedback module can detect the operating status of the thermocouple and generate an alarm signal when a deviation occurs, which is then transmitted to the control module for display. This helps to promptly identify and address potential problems, ensuring stable system operation and the quality of the wire.

[0024] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of an embodiment of the temperature control system for growing noble metal filaments using the micro-pull-down method according to the present invention;

[0026] Figure 2 This is a front cross-sectional view of the crystallizer tube in an embodiment of the temperature control system for growing noble metal filaments using the micro-pull-down method according to the present invention.

[0027] Figure 3 This is a front cross-sectional view of the crucible in an embodiment of the temperature control system for growing noble metal filaments using the micro-pull-down method of the present invention.

[0028] Figure 4 This is an enlarged schematic diagram of the solid-liquid interface in an embodiment of the temperature control system for growing precious metal filaments using the micro-pull-down method of the present invention.

[0029] The reference numerals in the accompanying drawings of the instruction manual include: 1. First thermocouple; 2. First flange; 3. Quartz tube; 4. Crucible; 5. Induction coil; 6. Seed crystal guide rod; 7. Second flange; 8. Circulating water cooling unit; 9. Gas pipe; 10. Crystallization tube; 11. Second thermocouple; 12. Grip roller; 13. Melt; 14. Meniscus; 15. Solid-liquid interface; 16. Magnetic conductor. Detailed Implementation

[0030] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0032] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0033] The following detailed description illustrates the specific implementation method:

[0034] Example 1:

[0035] As attached Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown: A temperature control system for growing precious metal filaments using a micro-pull-down method includes a crucible 4 and a quartz tube 3. A first flange 2 and a second flange 7 are respectively bonded to the top and bottom of the quartz tube 3. The crucible 4 is bonded inside the quartz tube 3. An induction coil 5 for heating and melting the precious metal is surrounded around the outside of the quartz tube 3. A first thermocouple 1 for detecting the temperature of the melt 13 formed by the melting of the precious metal is placed inside the crucible 4. A meniscus 14 for measuring the distance between the precious metal melt 13 and the solid is bonded to the bottom inner side of the crucible 4. A second thermocouple 11 for measuring the ambient temperature; a magnetic conductor 16 is provided around the outer ring of the induction coil 5; a cooling assembly is fixedly connected to the bottom of the second flange 7; a crystallizer connected to the inside of the crucible 4 is bonded to the center of the bottom of the crucible 4; the bottom end of the crystallizer passes through the second flange 7 and the cooling assembly in sequence; a seed crystal rod 6 is placed inside the crucible 4; the bottom of the seed crystal rod 6 passes through the crucible 4 and the crystallizer in sequence and extends to the outside, and the seed crystal rod 6 is slidably connected to the crystallizer and the crucible 4; the cooling assembly includes a circulating water cooling unit 8, which is made of copper. It also includes a collection assembly for drawing and collecting metal wires.

[0036] It also includes a control module, in which the first temperature-measuring thermocouple 1, the second temperature-measuring thermocouple 11, the induction coil 5, the cooling component, and the collection component are all connected to the control module via signals. This module is used to set the initial parameters required for the precious metal based on its physical properties, including the temperature of the circulating water cooling unit 8 and the melting temperature of the metal material. Simultaneously, it adjusts the output power of the induction coil 5 based on the monitoring data of the first and second temperature-measuring thermocouples 11. Furthermore, it controls the speed of the winding machine and the clamping roller 12 based on the actual production conditions of the precious metal wire, so as to grow the wire according to the preset pull-down speed parameters. It is also used to display the detection data of the first and second temperature-measuring thermocouples 11, and can set the target temperature at any point for temperature adjustment.

[0037] The collection components include a winding machine and a clamping roller 12. The clamping roller 12 and the winding machine are installed on the collection route of the finished precious metal fine wire. Both the clamping roller 12 and the winding machine are connected to the control module via signals.

[0038] The crystallizer has a first through hole that communicates with the crucible 4. The diameter of the first through hole at the end near the crucible 4 is equal to the diameter of the precious metal wire to be grown, and the diameter of the first through hole at the end away from the crucible 4 is greater than the diameter of the precious metal wire. The first through hole is frustum shaped as a whole. The bottom of the crucible 4 has a second through hole that communicates with the crystallization tube 10. The diameter of the second through hole is equal to the diameter of the precious metal wire to be grown.

[0039] The central axes of the flange, quartz tube 3, induction coil 5, crucible 4, crystallizer, cooling components and seed crystal guide rod 6 are all on the same vertical straight line.

[0040] In principle, this invention does not impose any particular restrictions on the conventional size of the through hole at the bottom of the crucible 4. Those skilled in the art can select and adjust it according to actual production conditions, raw material conditions and product requirements. In order to better grow small-diameter precious metal wires and ensure the performance of precious metal wires, the length of the through hole at the bottom of the crucible 4 is preferably 3 to 9 mm, more preferably 4 to 8 mm, and even more preferably 5 to 7 mm.

[0041] In principle, the material of the crucible 4 is not particularly limited in this invention. Those skilled in the art can select and adjust it according to the actual production situation, raw material situation and product requirements. In order to better grow small-diameter precious metal wires and ensure the performance of precious metal wires, the material of the crucible 4 preferably includes one or more of graphite, Al2O3, ZrO2 and BN.

[0042] In principle, the present invention does not impose any particular restrictions on the material of the crystallizer. Those skilled in the art can select and adjust the material according to the actual production situation, raw material conditions and product requirements. In order to better grow small-diameter precious metal wires and ensure the performance of precious metal wires, the material of the crystallizer preferably includes one or more of graphite, Al2O3, ZrO2 and BN, and more preferably graphite or BN.

[0043] In principle, this invention does not impose any particular restrictions on the length and diameter of the crystallizer. Those skilled in the art can select and adjust it according to actual production conditions, raw material conditions, and product requirements. In order to better grow small-diameter precious metal wires and ensure the performance of precious metal wires, the length of the crystallizer is preferably 100-150 mm, more preferably 110-140 mm, more preferably 120-130 mm, and the diameter is preferably 11-22 mm, more preferably 13-20 mm, more preferably 15-18 mm.

[0044] The specific implementation process is as follows: A precious metal material (powder, block, or wire) is loaded into the crucible 4. Taking PtIr10 alloy block as an example, and high-purity Al2O3 crucible 4 as an example, the parameters required for melting the PtIr10 alloy block are set, and then the temperature is increased by program. Then, the 2mm diameter seed crystal rod 6 is moved from the bottom of the crystallizer to pass through the bottom of the crucible 4, and the other end of the seed crystal rod 6 is fixed on the clamping roller 12. Then, a temperature control system for producing small-diameter precious metal wire by the μ-PD method is set up, and it is ensured that the center of the flange, quartz tube 3, induction coil 5, crucible 4, crystallizer, circulating water cooling unit 8 and seed crystal rod 6 are kept on the same vertical line. Turn on the circulating water cooling unit 8 switch again, set the water temperature to 20-30℃, and then start the induction coil 5 to heat the material to above 1800℃. After the material is completely melted, adjust the temperature of the meniscus 14 to be slightly lower than the melting point of the PtIr10 alloy, and observe the state of the melt 13. When the melt 13 wets the bottom of the entire crucible 4 and the side surface of the melt 13 does not bulge outward, adjust the rotation speed of the clamping roller 12, and pull down the seed crystal guide rod 6 along the

[100] direction to grow the filament, and obtain a PtIr10 filament with a diameter of less than 2mm and a length of more than 1000mm.

[0045] Example 2:

[0046] As attached Figure 1 As shown, the difference from Embodiment 1 is that the bottom of the circulating water cooling unit 8 is provided with a ventilation component for introducing inert gas into the bottom of the crystallization tube 10. The ventilation component includes a gas pipe 9 and a gas pump connected to the gas pipe 9.

[0047] The specific implementation process is as follows: When the seed crystal pull rod 6 is pulled down to grow the filament, the air pump is started and inert gas is slowly introduced into the filament forming area to reduce the possibility of oxidation of the filament with air at high temperature, thereby ensuring the quality of the finished product.

[0048] Example 3:

[0049] The difference from Embodiment 2 is that it also includes a feedback module, which is used to detect the working status of the first temperature measuring thermocouple 1 and the second temperature measuring thermocouple 11. When the change curve of the real-time temperature data detected by the first temperature measuring thermocouple 1 or the second temperature measuring thermocouple 11 deviates from the conventional change curve by more than a preset deviation, an alarm signal is generated and transmitted to the control module, which then displays the corresponding alarm image.

[0050] The specific implementation process is as follows: The feedback module monitors the output signal of the thermocouple in real time to determine whether its working status is normal. As a temperature sensing element, the thermocouple's output signal (i.e., thermoelectric potential) has a specific relationship with temperature. When the thermocouple is working normally, its output signal should change stably with temperature changes. However, when the thermocouple malfunctions or is damaged, its output signal may become abnormal, such as signal fluctuations, signal interruptions, or the signal not matching the actual temperature. Therefore, when the output signal of the first temperature-sensing thermocouple 1 or the second temperature-sensing thermocouple 11 exceeds the preset range or exhibits abnormal fluctuations, the feedback module will determine that the first temperature-sensing thermocouple 1 or the second temperature-sensing thermocouple 11 has malfunctioned or is damaged, and generate a corresponding alarm signal which is transmitted to the control module. The control module then displays the corresponding alarm image, allowing staff to promptly identify problems and ensure normal production.

[0051] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A temperature control system for growing noble metal filaments using a micro-pull-down method, comprising a crucible (4), characterized in that, It also includes a quartz tube (3), with a first flange (2) and a second flange (7) fixedly connected to the top and bottom of the quartz tube (3) respectively. A crucible (4) is placed inside the quartz tube (3). An induction coil (5) for heating and melting precious metals is surrounded around the outside of the quartz tube (3). A first thermocouple (1) for detecting the temperature of the melt (13) formed by the melting of precious metals is placed inside the crucible (4). A second thermocouple for measuring the temperature near the meniscus (14) between the precious metal melt (13) and the solid is placed at the bottom inside the crucible (4). The electrode (11) and the induction coil (5) are provided with a magnetic conductor (16) on the outside. A cooling component is fixedly connected to the bottom of the second flange (7). A crystallizer communicating with the inside of the crucible (4) is provided at the center of the bottom of the crucible (4). The bottom end of the crystallizer passes through the second flange (7) and the cooling component in sequence. A seed crystal rod (6) is provided inside the crucible (4). The bottom of the seed crystal rod (6) passes through the crucible (4) and the crystallizer in sequence and extends to the outside. The seed crystal rod (6) is slidably connected to the crystallizer and the crucible (4). It also includes a collection component for traction and collection of metal wire. It also includes a control module, in which the first temperature measuring thermocouple (1), the second temperature measuring thermocouple (11), the induction coil (5), the cooling component, and the collection component are all connected to the control module via signals; it is used to set the initial parameters required for the production of precious metal wire based on the physical properties of precious metal, and to adjust the output power of the induction coil (5) based on the monitoring data of the first temperature measuring thermocouple (1) and the second temperature measuring thermocouple (11), and to control the running speed of the collection component based on the actual production situation of the precious metal wire; it is also used to display the detection data of the first temperature measuring thermocouple (1) and the second temperature measuring thermocouple (11), and to set the target temperature of any point for temperature adjustment; The crystallizer has a first through hole that communicates with the crucible (4). The diameter of the first through hole at the end closest to the crucible (4) is equal to the diameter of the precious metal wire to be grown, and the diameter of the first through hole at the end furthest from the crucible (4) is greater than the diameter of the precious metal wire. The first through hole is shaped like a frustum.

2. The temperature control system for growing noble metal filaments using the micro-pull-down method according to claim 1, characterized in that, The central axes of the first flange (2), the second flange (7), the quartz tube (3), the induction coil (5), the crucible (4), the crystallizer, the cooling assembly, and the seed crystal pull rod (6) are all on the same vertical straight line.

3. The temperature control system for growing noble metal filaments using the micro-pull-down method according to claim 2, characterized in that, The cooling assembly includes a circulating water cooling unit (8) that is connected to the control module via a signal. The circulating water cooling unit (8) is made of copper.

4. The temperature control system for growing noble metal filaments using the micro-pull-down method according to claim 3, characterized in that, The collection assembly includes a clamping roller (12) for pulling precious metal filaments and a winding machine. The clamping roller (12) and the winding machine are set on the collection path of the finished precious metal filaments. Both the clamping roller (12) and the winding machine are connected to the control module via signals.

5. The temperature control system for growing noble metal filaments using the micro-pull-down method according to claim 4, characterized in that, The bottom of the crucible (4) has a second through hole that communicates with the crystallization tube (10). The diameter of the second through hole is equal to the diameter of the precious metal filament to be grown.

6. The temperature control system for growing noble metal filaments using the micro-pull-down method according to claim 5, characterized in that, The control module is also used to control the speed of the winding machine and the clamping roller (12) to grow the filament according to the preset pull-down speed parameters.

7. The temperature control system for growing noble metal filaments using the micro-pull-down method according to claim 6, characterized in that, The initial parameters include the temperature of the circulating water cooling unit (8) and the melting temperature of the metal material.

8. The temperature control system for growing noble metal filaments using the micro-pull-down method according to claim 7, characterized in that, The bottom of the circulating water cooling unit (8) is provided with a ventilation component for introducing inert gas into the bottom of the crystallization tube (10). The ventilation component includes a gas pipe (9) and a gas pump connected to the gas pipe (9).

9. The temperature control system for growing noble metal filaments using the micro-pull-down method according to claim 8, characterized in that, It also includes a feedback module, which is used to detect the working status of the first temperature measuring thermocouple (1) and the second temperature measuring thermocouple (11). When the change curve of the real-time temperature data detected by the first temperature measuring thermocouple (1) or the second temperature measuring thermocouple (11) deviates from the conventional change curve by more than a preset deviation, an alarm signal is generated and transmitted to the control module, which then displays the corresponding alarm image.

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