A crucible system for manufacturing nano-metal powder

Abstract

The present invention discloses a crucible system for manufacturing nano-metal powders, comprising a crucible body, a crucible insulation layer, a plasma torch heating system, an ion gas transmission device, a crucible cooling system, an automatic feeding device, a temperature control device, a pressure control system, a liquid level detection device, and a high-efficiency particle size control device. The present invention improves the preparation efficiency and quality of nano-metal powders through precise control, can monitor various parameters in real time, and ensures that the produced nano-powders meet predetermined requirements. The present invention can be widely used in electronics, materials science, energy storage and other fields, and has important economic and social significance.

Description

Technical Field

[0001] The invention belongs to a system for preparing nanometer powders from a single-element or multi-element metal alloy, and in particular relates to a crucible system for manufacturing nanometer metal powders. Background Art

[0002] The preparation of nanometal powders has important applications, such as as conductive materials in the electronics industry and as active components in catalysts. It also has significant applications in communications, 3D printing, sensors, and other fields. Current preparation methods include aerosol spraying, chemical methods, and electric explosion methods. However, these methods suffer from issues such as uneven particle size and low production efficiency. Therefore, an efficient and precise preparation method is urgently needed to meet practical needs.

[0003] The plasma method for producing ultrafine metal particles refers to a powder-making process that uses plasma as a heat source to provide energy. Plasma is a high-temperature, ionized, and conductive gaseous state generated by the contact of gas and an electric arc. Due to the conductivity of the ionized gas, the arc energy is rapidly transferred and converted into thermal energy in the gas, forming a high-temperature gas jet (temperatures exceeding 5500°C) and a high-intensity heat source. The plasma method is used to produce ultrafine powders with tiny particle sizes, which are difficult to produce using conventional processes, or materials with certain special surface properties.

[0004] The use of high-purity zirconia crucibles has the following advantages.

[0005] 1. High temperature resistance: Zirconia has a high melting point of 2700°C. Therefore, high-purity zirconia crucibles can maintain stable performance in high temperature environments.

[0006] 2. Good chemical stability: Zirconia has good chemical stability and is not easy to react with other chemicals. Therefore, it is suitable for various molten metals and compounds with strong chemical corrosiveness.

[0007] 3. No pollution: Zirconia is an environmentally friendly material that will not pollute the materials in the pot and is beneficial to improving the purity of the materials.

[0008] Zirconia crucibles have irreplaceable advantages in special environments such as high temperature and high corrosion, so they are still widely used in some high-end fields. Summary of the Invention

[0009] Based on the above requirements, the present invention provides a crucible system for manufacturing nano-metal powders.

[0010] The technical solution adopted by the present invention to solve the technical problem is: a crucible system for manufacturing nano-metal powders, comprising a crucible body, a crucible insulation layer arranged outside the crucible body, and a crucible cooling system arranged outside the crucible insulation layer, a plasma torch heating system connected to the crucible body, an ion gas transmission device for mixing one or more of nitrogen, hydrogen, and argon and transmitting them to the reaction system according to the process ratio, an automatic feeding device for automatically feeding raw materials, and a high-efficiency particle size control device with a certain inclination angle, and the crucible body is respectively provided with a temperature control device. The crucible body comprises a high-purity graphite crucible base that can withstand high temperatures of 3000-4000°C and a large crucible and a small crucible installed above the crucible base; the crucible insulation layer comprises insulation cotton surrounding the large and small crucibles and a stainless steel furnace body, and an insulating tube assembly is provided between the crucible base and the stainless steel furnace body to separate the crucible and the stainless steel furnace body for insulation; the ion gas transmission device comprises a nitrogen transmission pipeline with a nitrogen flow meter, a hydrogen flow meter with a The crucible cooling system includes a cold water circulation system surrounding the stainless steel furnace body and a nitrogen air cooling system arranged in the interlayer between the large crucible and the small crucible, and the crucible temperature is effectively controlled by cooling water and nitrogen air cooling; the automatic feeding device is used to automatically feed raw materials, including a feeding bin with a feeding inlet and a feeding outlet, a feeding motor and a feeding pipe with a certain angle to the crucible liquid surface, a feeding observation window with a high-temperature resistant lens, and a feeding window video transmission system; the liquid level detection device includes a feeding bin with a feeding inlet and a feeding outlet, a feeding motor and a feeding pipe with a certain angle to the crucible liquid surface, and a feeding observation window with a high-temperature resistant lens and a feeding window video transmission system. The scale has a high-temperature resistant metal liquid level probe and a liquid level control motor connected to the high-temperature resistant metal liquid level probe. The operator quickly raises and lowers the motor at regular intervals, and then observes the changes in the liquid level scale through the liquid level observation window video monitoring system; the nano powder control system includes an industrial control computer, a PLC and a solenoid valve; the high-efficiency particle size control device is an inner and outer double-layer sandwich design, which includes an outer layer of a stainless steel pipe and an inner jacket with dense pores evenly distributed in the horizontal direction. Normal temperature and high-pressure inert gas is introduced into the pores to quickly cool the evaporated powder and prevent the powder particles from continuing to grow after leaving the furnace.

[0011] The crucible system for manufacturing nano-metal powders, wherein the large crucible and the small crucible are graphite crucibles or high-temperature resistant ceramic crucibles, wherein the top cover of the crucible is provided with a dedicated plasma gun inlet, a temperature sensor inlet, a liquid level detection inlet, a feeding inlet and an air outlet; the ceramic crucible is an alumina / zirconia mixed crucible that can withstand temperatures up to 2000°C.

[0012] The crucible system for manufacturing nano-metal powders has a plasma torch heating system comprising an AC / DC converter, a DC power supply, a plasma arc ignition cabinet, an optical communication module, a pulse generator and a plasma gun connected in sequence, which is used to generate a high-temperature plasma state to achieve melting and gasification of the material.

[0013] Furthermore, the plasma gun includes a gun housing, a gun core, an arc nozzle, a plasma gun water-cooling pipe, a water flow meter, a plasma gun air-cooling pipe, a shielding gas inlet, a shielding gas outlet, and a gas flow meter. The gun housing and the gun core are respectively connected to the positive and negative poles of a DC power supply. The DC power supply is a plurality of parallel high-power power supplies. If a power supply fails during operation, the normal operation of other power supplies will not be affected. The gun housing and the gun core are respectively provided with a water inlet and a water outlet for cooling the plasma gun body and extending the service life of the plasma gun.

[0014] The temperature control device of the crucible system for manufacturing nano-metal powders includes a high-temperature resistant temperature sensor and an anti-magnetic field signal transmission module.

[0015] The crucible system for manufacturing nano-metal powders has a pressure control system comprising a variable frequency air compressor, a variable frequency Roots blower, an air storage tank, a digital pressure gauge and a variable frequency vacuum pump.

[0016] The present invention has the following beneficial effects: A high-power power supply assists the plasma gun in generating an arc, thereby melting the metal material and producing a vaporized state. Metal vaporization, condensation, and particle formation occur within the crucible system. Through the transmission of circulating gas, the nanoparticles gradually cool and enter a material collection device, ultimately achieving the goal of efficiently producing nanopowders.

[0017] The innovative design and precise control of the present invention make it a core tool for the efficient preparation of nanopowders, which has broad application prospects and can have a significant impact in fields such as electronics, materials science and energy storage.

[0018] Through innovative design and precise control, the present invention improves the preparation efficiency and quality of nano-metal powders, can monitor various parameters in real time, and ensure that the produced nano-powders meet predetermined requirements. It can be widely used in electronics, materials science, energy storage and other fields, and has important economic and social significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of the crucible, insulation cotton, and furnace cooling system of the present invention;

[0021] Figure 3It is a structural schematic diagram of the plasma torch heating system of the present invention;

[0022] Figure 4 Schematic diagram of the structure of the plasma gun of the present invention;

[0023] Figure 5 Schematic diagram of the structure of the ion gas transmission device of the present invention;

[0024] Figure 6 It is a structural schematic diagram of the automatic feeding device of the present invention;

[0025] Figure 7 It is a structural schematic diagram of the liquid level and temperature control device of the present invention;

[0026] Figure 8 This is a schematic structural diagram of the pressure control and nanopowder control system of the present invention;

[0027] Figure 9 This is a schematic diagram of the structure of the nanopowder crucible and power supply system of the present invention;

[0028] Figure 10 This is a scanning electron microscope test photo of a typical nano-metal material manufactured by the system of the present invention;

[0029] Figure 11 This is a photo of the laser particle size test of a typical nano-metal material manufactured by the system of the present invention.

[0030] The figures are marked as follows: 1—crucible body, 101—crucible base, 102—large crucible, 103—small crucible, 2—crucible insulation layer, 201—insulation cotton, 202—stainless steel furnace body, 203—insulation tube assembly, 3—plasma torch heating system, 301—plasma arc ignition cabinet, 304—DC power supply, 305—AC / DC converter, 306—plasma gun, 3061—gun housing, 3062—gun core, 3063—arc Nozzle, 3064—Plasma gun water cooling tube, 307—Optical communication module, 308—Pulse generator, 4—Ion gas transmission device, 401—Nitrogen transmission pipeline, 402—Hydrogen transmission pipeline, 403—Nitrogen flow meter, 404—Hydrogen flow meter, 405—Argon transmission pipeline, 406—Argon flow meter, 5—Crucible cooling system, 501—Cold water circulation system, 502—Nitrogen gas cooling system, 6—Automatic feeding device, 601 —Feeding bin, 602—Feeding motor, 603—Feeding pipe, 604—Feeding observation window, 605—Feeding window video transmission system, 7—Temperature control device, 701—High temperature resistant temperature sensor, 702—Anti-magnetic field signal transmission module, 8—Pressure control system, 801—Variable frequency air compressor, 802—Variable frequency Roots blower, 803—Air storage tank, 804—Digital pressure gauge, 805—Variable frequency vacuum pump, 9—Liquid level detection device, 901—High-temperature resistant metal liquid level probe, 902—Liquid level control motor, 10—Nano powder control system, 1001—Industrial control computer, 1002—PLC, 1003—Solenoid valve, 11—High-efficiency particle size control device, 1101—Outer layer, 1102—Inner jacket, 1201—Plasma gun inlet, 1202—Temperature sensor inlet, 1203—Liquid level detection inlet, 1204—Making material inlet, 1205—Gas outlet. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0032] Reference Figure 1 As shown, the present invention discloses a crucible system for manufacturing nano-metal powders, including a crucible body 1, a crucible insulation layer 2, a plasma torch heating system 3, an ion gas transmission device 4, a crucible cooling system 5, an automatic feeding device 6, a temperature control device 7, a pressure control system 8, a liquid level detection device 9, a nano-powder control system 10 and a high-efficiency particle size control device 11.

[0033] Reference Figure 2As shown, the crucible body 1 includes a high-purity graphite crucible base 101 that can withstand high temperatures of up to 3000-4000°C, and a large crucible 102 and a small crucible 103 installed above the crucible base 101. The carrier gas enters through the air outlet of the crucible base 101 and then flows evenly upward along the inner wall of the small crucible 103. The upward airflow can accelerate the evaporation of the metal liquid in the pot.

[0034] The large crucible 102 and the small crucible 103 are graphite crucibles or high-temperature resistant ceramic crucibles. The top cover of the crucible is provided with a dedicated plasma gun inlet 1201 (diameter 1-10 cm), a temperature sensor inlet 1202 (diameter 1-5 cm), a liquid level detection inlet 1203 (diameter 1-5 cm), a feeding inlet 1204 (diameter 1-10 cm), and an air outlet 1205 (diameter 10-30 cm). The advantage is that the scientific size design is adopted, which is conducive to improving the effective evaporation of metal and the output of powder.

[0035] The ceramic crucible is an alumina / zirconia mixed crucible that can withstand temperatures up to 2000°C. The excellent high-temperature resistance of the crucible ensures that the metal material will not damage the crucible body 1 and the measuring component after melting at high temperature in the pot, nor will it seep out of the crucible and damage the external system. The crucible system has a durability of 200 to 400 hours in a high-temperature environment of 1500°C.

[0036] The crucible insulation layer 2 includes insulation cotton 201 surrounding the outer crucible and a stainless steel furnace body 202. The advantage lies in the use of reasonable materials and size design. On the one hand, it can effectively protect the furnace body sealing ring from the direct impact of the high-temperature atmosphere and extend the service life of the system components. On the other hand, it can reduce heat loss in the boiler and increase the effective evaporation amount. The crucible insulation layer 2 uses high-temperature resistant insulation cotton 201 of a certain thickness, which can lock the core temperature and create a good high-temperature evaporation environment.

[0037] An insulating tube assembly 203 is installed between the crucible base 101 and the stainless steel furnace body 202. This T-shaped assembly, 2 to 4 cm thick, serves to insulate the crucible from the stainless steel furnace body 202. The crucible body 1 can withstand temperatures of up to 3000 to 4000°C. This excellent high-temperature resistance ensures that metal materials melted within the crucible without damaging the crucible body and measurement components, nor will they seep out of the crucible and damage external systems. The crucible system is rated for 200 to 400 hours of durability in high-temperature environments.

[0038] Reference Figure 3As shown, the plasma torch heating system 3 comprises a sequentially connected AC / DC converter 305, a DC power supply 304, a plasma arc ignition cabinet 301, an optical communication module 307, a pulse generator 308, and a plasma gun 306, configured to generate a high-temperature plasma state to melt and vaporize the material. The plasma torch heating system 3 is controlled by a control console that sequentially sends a set of instructions to the plasma arc ignition cabinet 301, the DC power supply 304, and the pulse generator 308 via the optical communication module 307. This then applies a high-frequency, high-voltage pulse signal between the cathode and anode of the plasma gun 306. Finally, an operator issues an ignition command to complete arc ignition.

[0039] Reference Figure 4 As shown, the plasma gun 306 includes an arc nozzle 3063, a gun housing 3061, and a gun core 3062, each connected to the positive and negative electrodes of a DC power supply 304. The DC power supply 304 comprises multiple high-power power supplies connected in parallel. If a single power supply fails during operation, the other power supplies remain operational. The gun housing 3061 and gun core 3062 are each equipped with a plasma gun water cooling pipe 3064, as well as a water inlet and outlet. The gun also includes a water flow meter, a plasma gun air cooling pipe, a shielding gas inlet and outlet, and a gas flow meter. The gun housing 3061 and gun core 3062 are each equipped with a water inlet and outlet to cool the plasma gun 306 and extend its service life.

[0040] Reference Figure 5 As shown, the ion gas transmission device 4 is used to transmit a mixture of one or more of nitrogen, hydrogen, and argon to the reaction system according to the process ratio. It includes a nitrogen transmission pipeline 401 with a nitrogen flowmeter 403, a hydrogen transmission pipeline 402 with a hydrogen flowmeter 404, and an argon transmission pipeline 405 with an argon flowmeter 406. The ion gas transmission device 4 uses a dedicated high-precision digital gas flowmeter. The flow rate of the ion gas can be accurately set and monitored in real time via a control console. The gas source is a mixture of two or more of high-purity argon, hydrogen, and nitrogen. The gas flow ratio is precisely designed. Using a reasonable ion gas ratio can produce a high-concentration plasma environment, which is beneficial for improving powder evaporation.

[0041] Reference Figure 6As shown, the automatic feeding device 6 is used to automatically feed raw materials, including a feeding bin 601 with a feeding inlet and a feeding outlet, a feeding motor 602, a feeding pipe 603 at a certain angle to the liquid surface of the crucible, a feeding observation window 604 with a high-temperature resistant lens, and a feeding window video transmission system 605. The operator monitors the liquid level in real time through the feeding window video transmission system 605. When the liquid level is lower than the process control lower limit, the main console will alarm to prompt that feeding is required. The operator sets the speed, frequency and other parameters of the feeding motor 602 on the main console to accurately control the feeding amount. When the liquid level after feeding reaches the process control range, the feeding is automatically stopped; the reasonable feeding angle design of the feeding pipe 603 can prevent the high-temperature droplets generated during feeding from splashing onto various sensor devices in the furnace and damaging the devices.

[0042] Reference Figure 7 、 Figure 8 and Figure 9 As shown, the crucible cooling system 5 includes a cold water circulation system 501 surrounding the stainless steel furnace body 202 and a nitrogen air cooling system 502 arranged in the interlayer between the large crucible 102 and the small crucible 103, which effectively controls the temperature of the crucible through cooling water and nitrogen air cooling.

[0043] A cooling water inlet and a cooling water outlet are provided on the outer wall of the stainless steel furnace body 202, and a high-precision water flow meter and a thermometer are respectively provided on the inlet and outlet water pipes of the cold water circulation system 501, which can monitor the inlet and outlet water flow and temperature in real time; the cold air circulation system recycles and reuses the pure cooling gas that has been cooled and filtered at the rear end of the equipment after leaving the stainless steel furnace body 202, and the temperature of the gas at the rear end is maintained at room temperature between 25 and 45°C. The gas is transported into the furnace body through a high-power Roots blower, which can carry the evaporation products to the rear collector on the one hand, and locally cool the outer wall of the crucible on the other hand, thereby protecting the crucible and extending its service life.

[0044] The temperature control device 7 includes a high-temperature resistant temperature sensor 701, an anti-magnetic field signal transmission module 702, and temperature control software that can be integrated into the main console. During the operation of the equipment, the main console collects temperature information in real time through the temperature control device 7 and displays it in a graph. The operator compares the temperature curve with the process temperature control limit, and then adjusts the temperature in the furnace in real time according to the temperature change to ensure the stability of the temperature parameters of the preparation process. The relative temperature in the furnace can be controlled at 1200-1300°C. Reasonable temperature control can effectively increase the evaporation rate of the powder.

[0045] The pressure control system 8 is used to maintain the air pressure of the working environment, and includes a high-power variable-frequency air compressor 801 , a variable-frequency Roots blower 802 , an air storage tank 803 , a digital pressure gauge and a variable-frequency vacuum pump 805 .

[0046] The liquid level detection device 9 includes a high-temperature resistant metal liquid level probe 901 with a scale and a liquid level control motor 902. The metal probe can withstand temperatures of up to 3000-3500°C. The operator quickly raises and lowers the motor at regular intervals, and then observes the changes in the liquid level scale through the liquid level observation window video monitoring system. When the liquid level is lower than the process control lower limit, the main control software will alarm on the display to remind employees that they need to add materials.

[0047] The nanopowder control system 10 includes an industrial controller 1001, nanopowder master control software, a programmable logic controller (PLC) 1002, and a solenoid valve 1003. The various parameters controlled by the nanopowder control system 10 include plasma gun current, plasma gun arc ignition voltage, the height between the plasma gun 306 and the material, plasma gun shielding gas flow rate, the height between the crucible pot edge and the liquid level, real-time crucible temperature, real-time internal pressure, internal humidity, real-time internal ONH content, real-time cooling water flow rate, cooling water inlet and outlet temperatures, real-time ion gas ratio, ion gas flow rate, the height between the liquid level and the plasma gun arc nozzle 3063, liquid level image, and high-efficiency circulating carrier gas flow rate. Parameters distributed throughout the system, such as temperature, pressure, humidity, online ONH content, gas flow rate, inlet and outlet water flow rate, arc voltage, ignition current, gun height, power supply power, and motor frequency, are transmitted via an anti-magnetic communication module. Parameter control functions are integrated into the master control software. System parameters are displayed on a large screen in a two-dimensional graphical format, allowing operators to observe data trends and make timely adjustments.

[0048] The highly efficient particle size control device 11 is tilted and features a double-layer design. The outer layer 1101 is a stainless steel pipe, while the inner jacket 1102 has dense, evenly distributed horizontal pores. Room-temperature, high-pressure inert gas is introduced into the pores to rapidly cool the evaporated powder and prevent further growth after exiting the furnace. The pores facilitate inert gas impact with the powder, preventing it from agglomerating. The ratio of pipe diameter to length is optimally controlled, and the unique pipe structure effectively improves evaporation efficiency.

[0049] The working principle of the present invention is as follows: A high-power power supply assists the plasma gun 306 in generating an arc, thereby melting the metal material and producing a vaporized state. Within the crucible system, processes such as metal vaporization, condensation, and granulation occur. Through the transmission of circulating gas, the nanoparticles gradually cool and enter a material collection device, ultimately achieving the goal of efficiently producing nanopowders. The innovative design and precise control of this crucible system make it a core tool for the efficient production of nanopowders, with broad application prospects and potential to have a significant impact in fields such as electronics, materials science, and energy storage.

[0050] This invention improves the production efficiency and quality of nanometal powders through innovative design and precise control. It has broad applications in electronics, materials science, energy storage, and other fields, and has significant economic and social significance. It also provides a comprehensive control system capable of real-time monitoring of various parameters to ensure that the produced nanopowders meet predetermined requirements.

[0051] The present invention enables safe and efficient control of the liquid-to-gas-to-liquid-to-solid transformation of metal materials. By adjusting power parameters, gas flow, temperature, and other factors, the metal's evaporation, condensation, growth, and particle formation processes can be precisely controlled to produce metal particles of varying sizes.

[0052] The high-efficiency air compressor and Roots blower used in the rear section of the present invention ensure that the pressure in the furnace and the pressure in the rear collection section are always in a balanced state; the device can be used to prepare copper powder, iron powder, silver powder, nickel powder or various alloy metals, with the sphericity controlled to be above 0.9, the oxygen content controlled to be between 1 and 2%, the particle size range controlled to be between 50 nm and 1500 nm, and the powder purity controlled to be above 99.5%.

[0053] The system of the present invention is used for small-batch production of nickel metal powder. The main typical parameters of the system are as follows: the internal temperature of the crucible system for nano-metal powder is controlled at 1200-1300°C, the arc voltage is controlled within 220V, the height of the plasma gun 306 is set to 50mm, and the preparation of nickel powder can be achieved by continuous operation for 200 hours. The laser particle size test D50 is 200-500nm, and the tap density is 1.8-5.2g / cm 3 , specific surface area 2.3 ~ 5.7㎡ / g, product purity up to 99.60%, of which C content 0.032%, Si content 0.013%, Cu content 0.0012%, Ca content 0.026%, Mg content 0.015%, S content 0.001%, P content 0.003%, B content 0.1%. Figure 10 shown.

[0054] The system of the present invention is used to carry out small-batch production of nickel metal powder. The main typical parameters of the system are as follows: the internal temperature of the crucible system of nano-metal powder is controlled at 1400-1500°C, the arc voltage is controlled within 250V, and the preparation of nickel metal powder can be achieved by continuous operation for 200 hours. The laser particle size test D50 of the produced sample is 127nm, the tap density is 1.97g / cm³, the specific surface area is 4.48㎡ / g, the C content is 0.037%, the Si content is 0.012%, the Cu content is 0.0016%, the Ca content is 0.022%, the Mg content is 0.011%, the S content is 0.001%, the P content is 0.003%, and the B content is 0.12%. Figure 11 shown.

[0055] The above description is only a preferred embodiment of the present invention, and the embodiment is not intended to limit the scope of patent protection of the present invention. Therefore, any equivalent structural changes made using the description and drawings of the present invention should be included in the scope of protection of the claims attached to the present invention.

Claims

1. A crucible system for producing nano-metal powders, characterized by: The invention comprises a crucible body (1), a crucible insulation layer (2) arranged outside the crucible body (1), and a crucible cooling system (5) arranged outside the crucible insulation layer (2), wherein the crucible cooling system (5) is provided with a plasma torch heating system (3) connected to the crucible body (1), an ion gas transmission device (4) for transmitting one or more mixed gases of nitrogen, hydrogen and argon according to a proportion, an automatic feeding device (6) for automatically feeding raw materials, and a high-efficiency particle size control device (11) with a certain inclination angle, and the crucible body (1) is provided with The crucible body (1) comprises a crucible base (101), a large crucible (102) and a small crucible (103) mounted on the crucible base (101); the crucible insulation layer (2) comprises insulation cotton (201) surrounding the crucible and a stainless steel furnace body (202); an insulating tube assembly is provided between the crucible base (101) and the stainless steel furnace body (202). (203); the ion gas transmission device (4) includes a nitrogen transmission pipeline (401), a hydrogen transmission pipeline (402) and an argon transmission pipeline (405); the crucible cooling system (5) includes a cold water circulation system (501) surrounding the stainless steel furnace body (202) and a nitrogen gas cooling system (502) arranged in the interlayer between the large crucible (102) and the small crucible (103); the automatic feeding device (6) includes a feeding bin (601), a feeding motor (602) and a feeding motor (603) with a certain distance from the crucible liquid surface. The feeding pipe (603) is provided at an angle; the liquid level detection device (9) includes a high-temperature resistant metal liquid level probe (901) and a liquid level control motor (902) connected to the high-temperature resistant metal liquid level probe (901); the nano powder control system (10) includes an industrial control machine (1001) and a PLC (1002); the high-efficiency particle size control device (11) includes an outer layer (1101) of a stainless steel pipe and an inner layer jacket (1102) with dense pores uniformly distributed in the horizontal direction, and inert gas is introduced into the pores.

2. The crucible system for producing nano-metal powder according to claim 1, characterized in that: The large crucible (102) and the small crucible (103) are graphite crucibles or high-temperature resistant ceramic crucibles. The top cover of the crucible is provided with a plasma gun inlet (1201), a temperature sensor inlet (1202), a liquid level detection inlet (1203), a feeding inlet (1204) and an air outlet (1205). The ceramic crucible is an alumina / zirconia mixed crucible.

3. The crucible system for producing nano-metal powder according to claim 1, characterized in that: The plasma torch heating system (3) comprises an AC / DC converter (305), a DC power supply (304), a plasma arc striking cabinet (301), an optical communication module (307), a pulse generator (308) and a plasma gun (306) connected in sequence.

4. The crucible system for producing nano-metal powder according to claim 3, characterized in that: The plasma gun (306) comprises an arc nozzle (3063), a gun housing (3061) and a gun core (3062) respectively connected to the positive and negative poles of a DC power supply (304), and a plasma gun water cooling pipe (3064) and a water inlet and a water outlet are respectively provided on the gun housing (3061) and the gun core (3062).

5. A crucible system for producing nano-metal powders according to claim 1, 2, 3 or 4, characterized in that: The feeding pipe (603) is provided with a feeding observation window (604) and a feeding window video transmission system (605).

6. The crucible system for producing nano-metal powder according to claim 5, characterized in that: The temperature control device (7) comprises a high-temperature resistant temperature sensor (701) and an anti-magnetic field signal transmission module (702).

7. The crucible system for producing nano-metal powder according to claim 6, characterized in that: The pressure control system (8) comprises a variable frequency air compressor (801), a variable frequency Roots blower (802), an air storage tank (803), a digital pressure gauge (804) and a variable frequency vacuum pump (805).

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