A nano metal production system and a control method thereof

Abstract

The application relates to the technical field of nano metal production, and particularly discloses a nano metal production system and a control method thereof. The nano metal production system comprises an evaporation chamber system, a melting pool for containing metal raw materials and an evaporation cavity with a heat preservation layer. The evaporation cavity wall surface is provided with a main process air inlet, a melting pool air inlet, a protection air inlet, an air outlet pipeline and an electric arc surrounding air inlet. The electric arc generation system comprises an electric arc generator arranged in the evaporation cavity. The evaporation chamber system is connected with an outlet gas temperature measuring device, a melting pool process air flow regulating valve, a melting pool process air outlet temperature measuring device, a melting pool heat preservation layer temperature measuring device, a circulating fan, a circulating air cooler and a cooling water flow regulating valve.

Description

Technical Field

[0001] This application relates to the field of nanometal production technology, and in particular to a nanometal production system and its control method. Background Technology

[0002] Due to their unique properties, nano-metal powders are widely used in coatings, plating, and other fields to improve workpiece surface properties and achieve high-precision manufacturing. Among the many preparation methods, the electric arc method is an ideal method for preparing nano-metal powders. It utilizes an electric arc to generate high-energy plasma to heat the metal raw materials in a crucible, causing them to evaporate.

[0003] The system yield of nanopowders is the product of the effective evaporation rate of the raw material and the effective evaporation area. The effective evaporation rate is positively correlated with the saturated vapor pressure and convective diffusion rate of the metal raw material. The higher the temperature of the raw material, the greater its saturated vapor pressure, and the greater the theoretical maximum evaporation rate. However, if the convective diffusion capacity is insufficient, the evaporated metal vapor cannot diffuse away from the evaporation surface in time, leading to some vapor recondensation and thus reducing the actual evaporation rate. Simultaneously, the evaporation temperature cannot be too high, otherwise the molten pool wall and insulation material will exceed their operating temperature and fail.

[0004] When metal vapor encounters a cold medium, it nucleates to form nanoparticles. These nanoparticles need to migrate towards the furnace outlet under the drag of gas. If the gas delivery capacity is insufficient, the particles will deposit inside the furnace and cannot be effectively transferred to the downstream collection system to form the product. Therefore, it is necessary to automatically adjust the arc current and the flow rate of process gas introduced into various parts of the furnace to control the evaporation rate of the metal raw materials, the nucleation particle size, and the particle transport, thereby achieving automated mass production of nanoparticles.

[0005] Existing technologies, such as the patent with authorization announcement number CN100457339C, disclose a method for preparing nano-metal powder by the simultaneous action of multiple electric arcs. Although this technology can provide high heat to evaporate the raw materials, it fails to explain how to form and maintain an effective evaporation area, nor does it explain in detail how to effectively diffuse the metal vapor into the process gas and smoothly carry it out of the furnace.

[0006] Another patent, CN116765410A, discloses a method and apparatus for producing metal nanoparticles, but does not elaborate on the specific effects of the air distribution structure, location, and air volume on the growth and transport of nanoparticles. Furthermore, excessive airflow through the arc sheath gas channel can lead to arc instability and cause more energy to be carried away by the gas, reducing energy utilization efficiency.

[0007] In summary, existing technologies still have shortcomings in achieving high yield, controllable particle size, and stable and efficient automated production of nanoparticles. Summary of the Invention

[0008] To address the shortcomings in high yield, controllable particle size, and stable and efficient automated production of nanopowders, this application provides a nano-metal production system and its control method.

[0009] In a first aspect, this application provides a nano-metal production system, which adopts the following technical solution:

[0010] A nanometal production system, comprising:

[0011] The evaporation chamber system includes an evaporation chamber with an insulation layer and a molten pool for containing metal raw materials. The walls of the evaporation chamber are provided with a main process air outlet, a molten pool air outlet, a protective air outlet, an air outlet duct, and an arc-encircling air outlet.

[0012] An electric arc generating system, including an electric arc generator disposed in an evaporation chamber;

[0013] The process air system includes a circulating fan and a circulating air cooler connected in sequence to the air outlet duct. The outlet of the circulating air cooler is connected to the main process air outlet, the molten pool ventilation outlet and the arc surround air outlet to form a circulating air path. The main process air outlet, the molten pool ventilation outlet and the arc surround air outlet are all equipped with air volume regulating valves and flow meters. A process air replenishment regulating valve is connected to one side of the circulating fan.

[0014] The air outlet duct is connected to an outlet gas temperature measuring device, the molten pool ventilation port is equipped with a molten pool process air outlet temperature measuring device, and the inner wall of the insulation layer is equipped with an insulation layer inner wall temperature measuring device.

[0015] By adopting the above technical solution, with the circulating fan as the main air source, the air volume of each vent is controlled by the air volume regulating valve and flow meter. The optimal power input under different working conditions is achieved by controlling the inlet and outlet gas temperature and the optimal transport speed, thus saving energy. At the same time, the molten pool wall and insulation material are protected from overheating. The minimum air intake volume into the furnace under different working conditions is achieved by controlling the inlet and outlet gas temperature and the optimal transport speed, thus achieving the minimum energy consumption. Through the automatic production control program, labor costs and energy consumption are saved to the maximum extent.

[0016] Optionally, the distance between the sidewall of the molten pool and the insulation layer is 50-100mm, and the vents of the molten pool are located on both sides of the molten pool.

[0017] Optionally, the top of the evaporation chamber is provided with a first ventilation pipe and an air outlet pipe. The first ventilation pipe is coaxially arranged with the evaporation chamber, and the air outlet pipe is inclinedly arranged on both sides of the first ventilation pipe. A second ventilation pipe is provided inside the first ventilation pipe, and a main process air outlet is formed between the first ventilation pipe and the second ventilation pipe. An air outlet is provided at the bottom of the first ventilation pipe, and the air outlet is connected to the main process air outlet. The electric arc generator is located inside the second ventilation pipe, and an electric arc surrounding air outlet is formed between the electric arc generator and the second ventilation pipe.

[0018] Optionally, the air outlet is vertically arranged on one side near the axis of the first ventilation pipe, and the other side of the air outlet is inclined towards the outer wall of the molten pool.

[0019] By adopting the above technical solution, the jet structure of the main process air and the air outlet ensures the convection diffusion rate of metal vapor and the transport capacity of nanoparticles, thereby improving the yield of nanoparticles.

[0020] Optionally, the air outlet duct is a Laval duct.

[0021] By adopting the above technical solutions, and by optimizing the position and tilt angle of the air outlet duct and adding a scaling nozzle structure, the problem of obstructed airflow due to turbulence can be avoided.

[0022] Optionally, a process air channel for the molten pool is formed between the molten pool and the insulation layer, and thermocouples are provided on both sides of the evaporation chamber. One end of the thermocouple passes through the evaporation chamber and extends into the process air channel for the molten pool.

[0023] By adopting the above technical solution and setting thermocouples, the input current can be controlled during operation, thereby controlling the melting area of ​​the material in the molten pool. This achieves the maximum melting and evaporation area of ​​the material under minimum power input, saving energy and protecting the sidewalls of the molten pool and the insulation layer from overheating.

[0024] Secondly, this application provides a control method for a nano-metal production system, employing the following technical solution:

[0025] A control method for a nanometal production system includes the following steps:

[0026] S1. Place the raw material in the molten pool and replace the air in the evaporation chamber with inert gas;

[0027] S2. Start the arc generator and adjust the voltage and generator height to the set values;

[0028] S3. Estimate the arc power based on the output, and initially set the current I, main process air flow rate Q1, molten pool process air flow rate Q2 and arc circulating air flow rate Q3.

[0029] S4. Once the molten pool temperature and the outlet gas temperature have stabilized, the automatic program is activated, and the system is automatically adjusted according to the above procedure.

[0030] Specifically, Q1 is measured by the air volume regulating valve installed in the main process vent, Q2 is measured by the air volume regulating valve installed in the molten pool vent, and Q3 is measured by the air volume regulating valve installed in the arc surround vent.

[0031] By adopting the above technical solution, the arc power is approximately the sum of furnace heat dissipation, powder evaporation heat, and all gas heating. The furnace heat dissipation value is fixed for the same equipment, while the powder evaporation heat is the product of output and evaporation heat per unit mass. Therefore, the arc power can be estimated by the output, and automatic control of the nano-metal production system can be achieved.

[0032] Optionally, the molten pool temperature T can be controlled by adjusting the input current I of the electric arc. m , making T m It is 200-300℃ higher than the melting point of the raw material, thus ensuring the maximum metal evaporation rate.

[0033] Optionally, the flow rate in the main flow zone of the furnace can be controlled by adjusting the total air volume Q1+Q2 introduced into the furnace to ensure the effective transport of metal vapor and nanoparticles.

[0034] Optionally, the system's input power P is related to the total air volume Q1+Q2+Q3 and the inlet / outlet temperature difference T. out -T in There is a relationship between them:

[0035] P = C P ·(Q1+Q2+Q3)·ρ·(T out -T in ), where C P ρ is the specific heat capacity, and ρ is the density.

[0036] Specifically, T out The gas temperature T measured by the thermocouple installed in the air outlet duct in The gas temperature measured by a thermocouple installed at the outlet of the circulating air cooler.

[0037] Optionally, there is a relationship between the main process air flow rate Q1, the molten pool process air flow rate Q2, the effective diffusion zone cross-sectional area A in the furnace, and the input current I of the electric arc:

[0038] Q1 + Q2 = k1A;

[0039] Q3=k2I.

[0040] Specifically, k1 and k2 are both set values. The purpose of k1 and k2 is to maintain the stability of the electric arc and ensure that the electrode tip does not overheat. k1 is determined by the structure of the evaporation chamber and is obtained from experimental data and simulation analysis. k2 is determined by the magnitude of the current and is derived from experiments and experience.

[0041] In summary, this application includes at least one of the following beneficial technical effects:

[0042] 1. Based on the current I, the air volume of each evaporator zone (Q1, Q2, Q3), and the molten pool temperature T... m The PLC control system automatically achieves the maximum evaporation area of ​​the molten pool and the optimal powder diffusion rate by combining key monitoring data such as gas outlet temperature, thus achieving the minimum energy consumption for the same powder output.

[0043] 2. With the implementation of the PLC system, when adjusting the operating conditions, only the total air volume needs to be adjusted manually. There is no need for operators to continuously observe the temperature of the molten pool and the gas temperature at the outlet of the evaporation chamber to make corresponding judgments and operations. The amount of operation is greatly reduced, which can save labor costs to the greatest extent and reduce the skill requirements of operators. At the same time, it avoids the occurrence of overheating of the molten pool wall and insulation material due to manual operation. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the structure of a nano-metal production system according to an embodiment of this application.

[0045] Figure 2 This is a schematic diagram of the evaporation chamber in an embodiment of this application.

[0046] Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0047] Figure 4 yes Figure 2 Enlarged view of point B in the middle.

[0048] Explanation of reference numerals in the attached drawings: 1. Evaporation chamber; 2. Insulation layer; 3. Receiving section; 4. Flow section; 5. Molten pool; 6. Molten pool process air passage; 7. Molten pool vent; 8. Thermocouple; 9. Protective air vent; 10. First ventilation duct; 11. Second ventilation duct; 12. Arc generator; 13. Arc surround air vent; 14. Main process air vent; 15. Air outlet; 16. Air outlet duct; 17. Outlet gas temperature measuring device; 18. Molten pool process air outlet temperature measuring device; 19. Inner wall temperature measuring device of insulation layer; 20. Filter; 21. Circulating fan; 22. Circulating air cooler; 23. Cooling water flow regulating valve; 24. Process air replenishment regulating valve; 25. Arc surround air regulating valve; 26. PLC control system. Detailed Implementation

[0049] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0050] Example

[0051] This application discloses a nanometal production system.

[0052] Reference Figure 1 and Figure 2 A nano-metal production system includes an evaporation chamber system, an electric arc generating system, a process air system, and a cooling collection system. The evaporation chamber system includes an evaporation chamber 1, with insulation layers 2 on both the inner wall and bottom. In this embodiment, the insulation layer 2 is made of zirconium oxide. The evaporation chamber 1 includes a receiving portion 3 and a flow portion 4. The receiving portion 3 is cylindrical, and the flow portion 4 is located above the receiving portion 3. The flow portion 4 is integrally formed with the receiving portion 3, and the interior of the flow portion 4 communicates with the interior of the receiving portion 3. The cross-sectional radius of the flow portion 4 is larger than that of the receiving portion 3. The inner wall of the flow portion 4 is provided with insulation layer 2, and the inner wall and bottom of the receiving portion 3 are also provided with insulation layer 2.

[0053] Reference Figure 2 and Figure 3 The receiving section 3 contains a molten pool 5, which is located at the bottom of the evaporation chamber 1 and embedded in the insulation layer 2. The molten pool 5 is a cylindrical crucible with an arc-shaped top, the center of which is lower than the sides. A gap exists between the sidewall of the molten pool 5 and the insulation layer 2 of the receiving section 3, forming a molten pool process air channel 6. In this embodiment, the width of the molten pool process air channel 6 is 50 mm. Two molten pool ventilation openings 7 are provided on the sidewall of the receiving section 3, extending horizontally through the receiving section 3 and the insulation layer 2. These openings are symmetrically arranged around the axis of the receiving section 3. Thermocouples 8 are installed on both sides of the receiving section 3, one end of which penetrates the sidewall of the receiving section 3 and extends into the molten pool process air channel 6. Thermocouples 8 are fixedly connected to the receiving section 3 and are located above the molten pool ventilation openings 7. The input current is controlled by thermocouple 8 to maintain the temperature at a level 200-300°C higher than the melting point of the raw material, thereby ensuring the maximum evaporation area while preventing the temperature of the molten pool 5 wall and the insulation layer 2 from becoming too high.

[0054] Reference Figure 2 A protective air vent 9 is provided on the side wall of the circulation section 4, and the protective air vent 9 penetrates the circulation section 4 and the insulation layer 2 in the horizontal direction. There are two protective air vents 9, and the two protective air vents 9 are symmetrically arranged around the axis of the circulation section.

[0055] Reference Figure 2The top of the circulation section 4 is provided with a first ventilation pipe 10 and a second ventilation pipe 11. The first ventilation pipe 10 is a cylinder with its opening facing upwards. One end of the first ventilation pipe 10 passes through the circulation section 4 and extends into the circulation section 4. The first ventilation pipe 10 is fixedly connected to the circulation section 4, and its axis coincides with the axis of the evaporation chamber 1. The second ventilation pipe 11 is a cylinder with openings at both ends. The second ventilation pipe 11 is located inside the first ventilation pipe 10. One end of the second ventilation pipe 11 passes through the bottom of the first ventilation pipe 10 and extends into the circulation section 4. The second ventilation pipe 11 is fixedly connected to the first ventilation pipe 10, and its axis coincides with the axis of the first ventilation pipe 10.

[0056] Reference Figure 2 and Figure 4 An arc generator 12 is slidably connected inside the second ventilation duct 11, forming an arc-encircling vent 13 between the second ventilation duct 11 and the arc generator 12. A main process vent 14 is formed between the first ventilation duct 10 and the second ventilation duct 11. An air outlet 15 is opened at the bottom of the first ventilation duct 10, and the air outlet 15 is connected to the main process vent 14. The air outlets 15 are symmetrically arranged on both sides of the second ventilation duct 11. The side of the air outlet 15 closest to the axis of the first ventilation duct 10 is vertically arranged, and the bottom of the other side of the air outlet 15 is inclined towards the outer wall of the molten pool 5.

[0057] Reference Figure 2 The top of the circulation section 4 is provided with two air outlet ducts 16, which are symmetrically arranged on both sides of the first ventilation duct 10. The axis of the air outlet duct 16 forms a 30° angle with the axis of the first ventilation duct 10. One end of the air outlet duct 16 passes through the circulation section 4, and the air outlet duct 16 is fixedly connected to the circulation section 4. A reducing nozzle is provided inside the air outlet duct 16, that is, the air outlet duct 16 is a Laval duct. The total area of ​​the openings of the air outlet duct 16 is greater than the sum of the areas of all process air inlets.

[0058] Reference Figure 1The process air system includes a circulating fan 21 and a circulating air cooler 22. The outlet of the circulating air cooler 22 is connected to the main process air outlet 14, the molten pool ventilation outlet 7, and the arc surround air outlet 13, forming a circulating air path. Airflow regulating valves and flow meters are installed in the main process air outlet 14, the molten pool ventilation outlet 7, and the arc surround air outlet 13. The cooling collection system includes a filter 20 for collecting nano-metal particles. An outlet gas temperature measuring device 17 is connected to the outlet air duct 16, a molten pool process air outlet temperature measuring device 18 is connected to the molten pool ventilation outlet 7, and an insulation layer inner wall temperature measuring device 19 is connected to the evaporation chamber 1. The outlet air duct 16 is connected to the filter 20, which is sequentially connected to the circulating fan 21, the circulating air cooler 22, and the cooling water flow regulating valve 23. Both the circulating fan 21 and the circulating air cooler 22 are connected to the process air makeup regulating valve 24. The arc-shaped air vent 13 is connected to the arc-shaped air regulating valve 25. All of the above structures are connected to the PLC control system 26 and are controlled by the PLC control system 26.

[0059] The implementation principle of a nano-metal production system in this application is as follows:

[0060] The operation of each system is controlled by a PLC control system 26, which controls the current I, the air volume of each evaporator zone (Q1, Q2, Q3), and the molten pool temperature T. m By combining key monitoring data such as gas outlet temperature with the PLC control system, the maximum evaporation area of ​​the molten pool 5 and the optimal powder diffusion rate are automatically achieved, resulting in the minimum energy consumption for the same powder production.

[0061] Application examples

[0062] This application discloses a control method for a nano-metal production system, which is implemented in a nano-metal production system disclosed in the embodiment, and includes the following steps:

[0063] P1. Add an appropriate amount of nickel into the molten pool 5, and adjust the arc generator 12 to the set height. Start the vacuum pump unit to reduce the pressure in the evaporation chamber 1 to 10. -4 The pressure is increased to 0.01 MPa (A) and then sufficient inert gas is introduced to restore the pressure to 0.01 MPa (A). This process is repeated three times to ensure a reliable inert atmosphere inside the furnace.

[0064] P2. Start the process air supply regulating valve 24 and the arc circulating air regulating valve 25. Set the arc circulating air volume to 50 SLPM, the molten pool process air volume to 200 SLPM, and the main process air volume to 300 SLPM.

[0065] P3. Start the power supply of the arc generator 12 to establish an arc between the arc generator 12 and the molten pool 5 metal raw material. Gradually increase the single arc current to 200 A. Move the position of the arc generator 12 to maintain it near the set voltage. The voltage is set according to the production requirements. In this application example, the set voltage U=100V.

[0066] P4. After the temperature field in evaporation chamber 1 stabilizes, engage the automatic control system: set the furnace outlet temperature T. out =800-1200K, intake air temperature T in At room temperature, the total air volume Q = P / [C] P ·ρ·(T out -T in P = UI - heat dissipation power - heat of powder evaporation;

[0067] When the system circulating air volume Q is insufficient, it is manually supplemented through the process air replenishment regulating valve 24. The process air replenishment regulating valve 24 is connected to the air source (nitrogen station). The pressure in the evaporation chamber 1 is automatically maintained by the frequency adjustment of the circulating fan 21.

[0068] P5, Melt Pool 5 Process Air Outlet Temperature T m The temperature is set to 1800-2000K, and the PLC system automatically adjusts the current I based on this temperature.

[0069] P6. After the adjusted current I signal is fed back to the PLC system, the PLC system will interlock and adjust the opening degree of the arc-suspension air regulating valve 25 according to the built-in logic (Q3= k2I, k2=0.25).

[0070] P7. Set the molten pool process air Q2 to remain constant, ensuring the air velocity in channel 5 of the molten pool is not lower than 0.2 m / s. Adjust the main process air according to the built-in logic (Q1 = k1A - Q2); in this application example, A = 0.1 m / s. 2 k1=0.5. According to T out The opening degree of the automatic cooling water flow regulating valve 23 is adjusted to control the cooling water flow.

[0071] Among them, Q1 is measured by the air volume regulating valve installed in the main process duct, Q2 is measured by the air volume regulating valve installed in the molten pool vent, Q3 is measured by the air volume regulating valve installed in the arc surround duct, and T out The gas temperature T measured by the thermocouple installed in the air outlet duct in The gas temperature measured by a thermocouple installed at the outlet of the circulating air cooler.

[0072] In this application example, the system output is 2 kg / h. When adjusting the operating conditions, only the total air volume needs to be adjusted manually. There is no need for operators to continuously observe the temperature of the molten pool 5 and the outlet gas temperature of the evaporation chamber 1 to make corresponding judgments and operations. The amount of operation is greatly reduced, which can save labor costs to the greatest extent and reduce the skill requirements of operators. At the same time, it avoids the overheating of the molten pool 5 wall and insulation material caused by manual operation.

[0073] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A control method of a nanometal production system, characterized by, For controlling a nano-metal production system, the nano-metal production system comprising: The evaporation chamber system includes an evaporation chamber (1) with an insulation layer (2) and a molten pool (5) for containing metal raw materials. The walls of the evaporation chamber (1) are provided with a main process air vent (14), a molten pool vent (7), a protective air vent (9), an air outlet duct (16), and an arc-encircling air vent (13). An electric arc generating system includes an electric arc generator (12) disposed in an evaporation chamber (1); The process air system includes a circulating fan (21) and a circulating air cooler (22) connected in sequence to the air outlet duct (16). The outlet of the circulating air cooler (22) is connected to the main process air outlet (14), the molten pool ventilation outlet (7) and the electric arc surrounding air outlet (13) to form a circulating air path. The main process air outlet (14), the molten pool ventilation outlet (7) and the electric arc surrounding air outlet (13) are all equipped with air volume regulating valves and flow meters. A process air replenishment regulating valve (24) is connected to one side of the circulating fan (21), and a cooling water flow regulating valve (23) is connected to one side of the circulating air cooler (22). The air outlet duct (16) is connected to an outlet gas temperature measuring device (17), the molten pool ventilation port (7) is equipped with a molten pool process air outlet temperature measuring device (18), and the inner wall of the insulation layer (2) is equipped with an insulation layer inner wall temperature measuring device (19). The control method for the nanometal production system includes the following steps: S1. Place the raw material in the molten pool (5) and replace the air in the evaporation chamber (1) with inert gas; S2. Start the arc generator (12) and adjust the voltage U and generator height to the set values; S3. Estimate the arc power based on the output, and initially set the current I, main process air flow rate Q1, molten pool process air flow rate Q2 and arc circulating air flow rate Q3. S4, when the temperature of the molten pool (5) and the outlet gas temperature tend to be stable, put into the automatic program: the input power P = C of the system P · (Q1+Q2+Q3) · p · (T out -T in ), wherein C P is the specific heat capacity of inert gas, p is the density of inert gas, T out -T in is the temperature difference between the inlet and outlet of the furnace body; When the system's circulating air volume Q1+Q2+Q3 is insufficient, it should be manually replenished.

2. The control method of a nano metal production system according to claim 1, wherein: The distance between the side wall of the molten pool (5) and the insulation layer (2) is 50-100mm, and the vent (7) of the molten pool is located on both sides of the molten pool (5).

3. The control method of a nano metal production system according to claim 2, wherein: The top of the evaporation chamber (1) is provided with a first ventilation pipe (10) and an air outlet pipe (16). The first ventilation pipe (10) is coaxially arranged with the evaporation chamber (1). The air outlet pipe (16) is inclinedly arranged on both sides of the first ventilation pipe (10). A second ventilation pipe (11) is provided inside the first ventilation pipe (10). A main process air outlet (14) is formed between the first ventilation pipe (10) and the second ventilation pipe (11). An air outlet (15) is provided at the bottom of the first ventilation pipe (10). The air outlet (15) is connected to the main process air outlet (14). The electric arc generator (12) is located inside the second ventilation pipe (11). An electric arc surrounding air outlet (13) is formed between the electric arc generator (12) and the second ventilation pipe (11).

4. The control method of a nano-metal production system according to claim 3, wherein: The air outlet (15) is vertically arranged on one side near the axis of the first ventilation pipe (10), and the other side of the air outlet (15) is inclined towards the outer wall of the molten pool (5).

5. The control method of a nano metal production system according to claim 2, wherein: A molten pool process air channel (6) is formed between the molten pool (5) and the insulation layer (2). Thermocouples (8) are provided on both sides of the evaporation chamber (1). One end of the thermocouple (8) passes through the evaporation chamber (1) and extends into the molten pool process air channel (6).

6. The control method of a nano metal production system according to claim 1, wherein: The temperature T of the molten bath (5) is controlled by adjusting the input current I of the electric arc m so that T m is 200-300°C higher than the melting point temperature of the raw material.

7. The control method of a nano metal production system according to claim 1, wherein: The flow rate in the main flow zone of the furnace is controlled by adjusting the total air volume Q1+Q2 introduced into the furnace to ensure the effective transport of metal vapor and nanoparticles.

8. The control method of a nano metal production system according to claim 1, wherein: There is a relationship between the main process airflow Q1, the molten pool process airflow Q2, the arc surround airflow Q3, the effective diffusion zone cross-sectional area A in the furnace, and the arc input current I: Q1 + Q2 = k1A; Q3 = k2I; Here, k1 and k2 are both set values.

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