Vacuum consumable arc melting and ultrasonic atomization-based powder production system and method

Abstract

The present invention provides a vacuum consumable arc melting and ultrasonic atomization-based powder production system and method. By using a metal or alloy bar as a cathode, a micro-molten pool is formed by means of consumable arc remelting, and by using ultrasonic waves as an energy source for atomization powder production, liquid metal or alloy is sputtered or forms metal mist under the action of the ultrasonic waves. Producing powder in a vacuum environment can obtain powder particles having high sphericity (≥ 0.95), high density (≥ 99%) and narrow particle size distribution (≤ 60 µm), meeting the powder usage requirements of powder near-net forming technologies such as additive manufacturing and powder metallurgy, and achieving preparation of high-melting-point and even refractory metal and alloy powder.

Description

Vacuum consumable arc melting ultrasonic atomization powder making system and method Technical Field

[0001] The present invention relates to the technical field of production and preparation of metal powder materials, and in particular to a vacuum consumable arc melting ultrasonic atomization powder making system and method. Background Art

[0002] Metal powder is a key raw material for near-net-shape powder forming technologies such as additive manufacturing and powder metallurgy. Its properties significantly influence the stability of the forming process and the quality of the final product. Spherical metal powders, due to their excellent sphericity, surface finish, and suitable particle size distribution, effectively guarantee process properties such as powder flowability and bulk density. This has positive implications for expanding the forming process window and improving the stability and consistency of part performance, leading to their widespread application.

[0003] At present, the mainstream technology for preparing spherical metal powder is atomization, which specifically includes gas atomization, centrifugal atomization, plasma atomization and other processes. Among them, gas atomization is the most widely used, but there are defects such as satellite powder and hollow powder; the plasma rotating electrode atomization method produces powders with high sphericity and surface smoothness, but compared with gas atomization, the fine powder yield is low and the raw material requirements (dimensional tolerance) are relatively high, resulting in no advantage in manufacturing costs and limiting large-scale applications; plasma atomization technology has significantly improved the fine powder yield, but the manufacturing efficiency is relatively low.

[0004] Ultrasonic atomization to prepare metal powder is an emerging powder making technology. Its principle is to use ultrasonic high-frequency vibration to generate directional pressure on the metal melt, causing the surface of the metal melt to bulge and rupture, producing metal droplets. For low-viscosity melts, it can even produce metal mist. Therefore, it is mostly used to prepare low-melting-point metal powders, such as tin powder.

[0005] By integrating multiple systems, the ultrasonic atomization method, which uses wires and rods as raw materials and lasers as the melting heat source, can also be used to prepare high-temperature alloy powders such as stainless steel and nickel-based alloys. However, during the preparation process, the metal droplets produced by laser melting freely fall onto the ultrasonic vibrating screen. Due to the loss of the heat source, the superheat continues to decay during the droplet's fall and contact with the screen surface, and the droplet viscosity increases, which is not conducive to the subsequent droplet breakage and spheroidization process. It is difficult to obtain metal powder with a particle size of ≤150μm and a sphericity of ≥0.95.

[0006] Prior art literature:

[0007] Chinese Patent: CN113664208A

[0008] Summary of the Invention

[0009] The purpose of the present invention is to address the shortcomings of the existing ultrasonic atomization in the preparation of metal powders, and to provide a vacuum consumable arc melting ultrasonic atomization powder making system and method, which can heat and melt the metal or alloy raw materials, and refine and cool them through physical action to obtain spherical metal powders with high sphericity and narrow particle size distribution, which can meet the powder requirements of powder near-net forming technologies such as additive manufacturing and powder metallurgy; at the same time, it can effectively avoid the defects such as hollow powder and satellite powder that are easily produced by the gas atomization process, solve the problem that the preparation of metal powders by ultrasonic atomization is limited to the low melting point metal range, and realize the preparation of high melting point and even refractory metal and alloy powders.

[0010] According to a first aspect of the present invention, a vacuum consumable arc melting ultrasonic atomization powder making system is provided, comprising:

[0011] The transmission and conductive system is provided with a clamping and conductive device, wherein a first end of the clamping and conductive device is connected to a driving device and a power supply device, and is used to provide feeding power and electric energy for the clamping and conductive device;

[0012] A vacuum chamber, wherein a first channel and a second channel are provided on a side wall of the vacuum chamber, the vacuum chamber is evacuated through the first channel, and air is replenished into the vacuum chamber through the second channel, so that the vacuum chamber reaches a desired pressure condition;

[0013] A circulating water cooling system is provided in the side wall of the vacuum chamber, and the side wall of the vacuum chamber is kept at a cooling temperature required for powder making by the circulating water cooling system;

[0014] The upper end surface of the vacuum chamber is provided with a through hole, and the second end of the clamping and conducting device passes through the through hole and is connected to the powder making system provided in the vacuum chamber;

[0015] The powder making system includes an electrode bar, a smelting device and an ultrasonic generator. The electrode bar is connected and fixed to the second end of the clamping and conductive device so that the working end surface of the electrode bar is located directly above the smelting device. The ultrasonic generator is provided below the smelting device.

[0016] Driven by the clamping and conductive devices, the electrode rod descends, and the electric energy generates an arc between the electrode rod and the smelting device, thereby melting the working end face of the electrode rod and generating a molten pool in the smelting device. Under the action of the ultrasonic generator, the molten liquid in the molten pool is broken up by the ultrasonic wave and sputtered out to produce droplets. The droplets contact with the side wall of the vacuum chamber and cool, solidify to form metal or alloy particles, and fall into the powder collecting device connected to the lower end face of the vacuum chamber for collection.

[0017] As an optional embodiment, the lower end of the vacuum chamber is configured as a cone with a larger upper portion and a smaller lower portion, and the lower portion of the cone is connected to the powder collecting device.

[0018] As an optional embodiment, the second channel is provided on the wall surface of the vertebral body.

[0019] As an optional embodiment, a sealing device is provided at the through hole where the second end of the clamping and conducting device enters the vacuum chamber.

[0020] According to a second aspect of the present invention, there is provided a method for preparing metal or alloy powder using the aforementioned vacuum consumable arc melting ultrasonic atomization powder making system, comprising the following steps:

[0021] One end of the metal or alloy bar is connected and fixed to the clamping and conductive device as the electrode bar, and the other end of the metal or alloy bar is positioned directly above the smelting device as the working end surface;

[0022] The vacuum chamber is sealed and evacuated until it reaches the first pressure range. If the metal or alloy bar contains volatile elements, the vacuum chamber is controlled to be within the second pressure range by adding inert gas, and the circulating water cooling system in the side wall of the vacuum chamber is started to maintain the side wall of the vacuum chamber within the required temperature range.

[0023] The clamping and conductive devices are driven to drive the electrode bar to descend until the required distance between the electrode bar and the melting device is reached. Then, the power supply device and the ultrasonic generator are started according to the output power of the power supply device and the frequency of the ultrasonic generator set by the preset parameters to complete arc initiation and generate ultrasonic waves.

[0024] Adjust the parameters according to the preset process and actual effect, and start powder making after confirming that the arc state and the molten pool page state are normal;

[0025] Among them, the electrode rod is used as the cathode and the smelting device is used as the anode. After the power is turned on and the arc is struck, the working end face of the electrode rod is heated and gradually melted, and continuously drips into the smelting device. The arc between the cathode and anode continuously heats the melt in the smelting device and forms a molten pool. The molten liquid in the molten pool is broken by the ultrasonic impact, and the formed droplets splash or flow to the outside of the smelting device and contact the side wall of the vacuum chamber, cooling and solidifying to form metal or alloy particles.

[0026] As an optional embodiment, the first pressure range is not higher than 6.5×10 -2 Pa, the second pressure range is 1×10 4 Pa~4×10 4 Pa.

[0027] As an optional embodiment, the temperature of the side wall of the vacuum chamber is maintained below 40°C.

[0028] As an optional embodiment, the electrode bar material descends at a speed of 5 mm / min to 100 mm / min, and the electrode bar material descends until the distance between the electrode bar material and the smelting device reaches 30 mm to 50 mm.

[0029] As an optional embodiment, the output power of the power supply device is adjusted by controlling the current size, which is between 500A and 3500A; the initial frequency of the ultrasonic generating device is between 5kHz and 15kHz, and the frequency during stable powder making is between 20kHz and 60kHz.

[0030] As an optional embodiment, the diameter of the electrode rod is between 5mm and 150mm, and the length is between 200mm and 2500mm.

[0031] Compared with the prior art, the present invention has the following significant beneficial effects:

[0032] 1. The vacuum consumable arc melting ultrasonic atomization powder making system of the present invention adopts ultrasonic waves as the energy source for atomization powder making. Under the action of ultrasonic waves, liquid metal or alloy produces sputtering or forms metal mist. The particle motion velocity field has a lower gradient than that of gas atomization, the droplet size distribution is narrower, and there is no swirling airflow effect, which reduces the collision probability of particles of different sizes, effectively avoids the problems of hollow powder and satellite powder that are easily generated under the gas atomization process, and is conducive to obtaining powder particles with high sphericity (≥0.95), high density (≥99%), and narrow particle size distribution (≤60μm).

[0033] 2. The powder making system of the present invention uses metal or alloy rods as cathodes and forms a micro-molten pool through consumable arc remelting, which ensures the superheat of the melt required for atomization powder making, is conducive to promoting the sputtering of molten droplets and even cavitation to form metal mist (fine droplets), and at the same time simplifies the structural composition of the smelting atomization system, which has a positive effect on improving the purity of the powder and reducing the introduction of impurities.

[0034] 3. The powder making system and method of the present invention are applicable to a wide variety of materials. In addition to conventional titanium alloys and nickel-based high-temperature alloys, refractory metals and alloys, and light metals and alloys are also applicable. At the same time, the raw material electrode can be an electrode rod pressed from a single element material, and the powder preparation is completed in the same system through arc melting-ultrasonic atomization, eliminating the related steps of preparing prefabricated master alloy rods, which is beneficial to reducing the cost of powder manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG1 is a schematic structural diagram of a vacuum consumable arc melting ultrasonic atomization powder making system according to the present invention.

[0036] FIG2 is a schematic diagram of the partial structure of the vacuum consumable arc melting ultrasonic atomization powder making system of the present invention.

[0037] FIG3 is a flow chart of the vacuum consumable arc melting ultrasonic atomization powder making method of the present invention.

[0038] Explanation of the accompanying reference numerals: 100, transmission conductive system; 110, clamping and conductive device; 200, vacuum chamber; 210, first channel; 220, second channel; 300, powder making system; 310, electrode rod material; 320, melting device; 330, ultrasonic generating device; 340, electric arc; 350, molten pool; 360, liquid droplets; 400, powder collecting device; 500, metal or alloy particles. DETAILED DESCRIPTION

[0039] In order to better understand the technical content of the present invention, specific embodiments are given and described below with reference to the accompanying drawings.

[0040] Various aspects of the present invention are described in this disclosure with reference to the accompanying drawings, in which a number of illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to be comprehensive. It should be understood that the various concepts and embodiments described above, as well as those described in more detail below, can be implemented in any of a number of ways.

[0041] Vacuum consumable arc melting ultrasonic atomization powder making system

[0042] 1 and 2 , an exemplary vacuum consumable arc melting ultrasonic atomization powder making system of the present invention includes:

[0043] The transmission conductive system 100 is provided with a clamping and conductive device 110. The first end of the clamping and conductive device 110 is connected to the driving device and the power supply device, and is used to provide feeding power and electric energy for the clamping and conductive device. The second end of the clamping and conductive device 110 is connected to the electrode rod in the powder making system, and is used to provide descending power to the electrode rod and electric energy for arc striking.

[0044] The vacuum chamber 200 has a first channel 210 and a second channel 220 on its side wall. The vacuum chamber 200 is evacuated through the first channel 210, and is supplied with air through the second channel 220, so that the vacuum chamber reaches the required pressure condition. A circulating water cooling system is provided on the side wall of the vacuum chamber 200, so that the side wall of the vacuum chamber is maintained at the cooling temperature required for powder making.

[0045] In an optional embodiment, the first channel 210 is provided at the upper portion of the side wall of the vacuum chamber, and the second channel 220 is provided at the lower portion of the side wall of the vacuum chamber, and a plurality of the first channel and the second channel can be provided.

[0046] It can be understood that in order to ensure the sealing of the vacuum chamber, sealing devices are provided at the first channel and the second channel.

[0047] A through hole is provided on the upper end surface of the vacuum chamber 200 , and the second end of the clamping and conductive device 110 passes through the through hole and is connected to the powder making system 300 provided in the vacuum chamber; the lower end of the vacuum chamber 200 is connected to the powder collecting device 400 .

[0048] In an optional embodiment, the lower end of the vacuum chamber 200 is configured as a cone with a larger upper portion and a smaller lower portion, the lower portion of the cone is connected to the powder collecting device 400, and the second channel 220 is provided on the wall of the cone.

[0049] In another optional embodiment, a baffle is provided at the connection between the vacuum chamber 200 and the powder collecting device 400, which opens automatically at regular intervals to allow the powder accumulated at the lower end of the vacuum chamber to fall into the powder collecting device.

[0050] In another optional embodiment, a sealing device is provided at the through hole where the second end of the clamping and conducting device enters the vacuum chamber, thereby ensuring the sealing of the entire vacuum chamber.

[0051] As shown in Figure 2, the powder making system 300 includes an electrode rod 310, a smelting device 320 and an ultrasonic generator 330. The electrode rod 310 is connected and fixed to the second end of the clamping and conductive device 110 so that the working end face of the electrode rod 310 is located directly above the smelting device 320. The ultrasonic generator 330 is provided below the smelting device 320.

[0052] In an optional embodiment, the smelting device 320 may use a copper crucible with a water-cooling channel, and a hemispherical smelting station is provided in the center of the crucible.

[0053] Driven by the clamping and conductive device 110, the electrode rod 310 descends, and electric energy generates an arc 340 between the electrode rod 310 and the melting device 320, thereby melting the working end face of the electrode rod 310 and generating a molten pool 350 in the melting device 320. Under the action of the ultrasonic generator 330, the molten liquid in the molten pool 350 is shattered by the ultrasonic wave and sputtered out to produce droplets 360. The droplets 360 contact the side wall of the vacuum chamber, cool, solidify and form metal or alloy particles 500, which fall into the powder collecting device 400 connected to the lower end face of the vacuum chamber for collection.

[0054] It can be understood that the electrode rod material is a rod material made of raw metal or alloy. The diameter of the electrode rod material is preferably between 5 mm and 150 mm, and the length is preferably between 200 mm and 2500 mm.

[0055] Vacuum consumable arc melting and ultrasonic atomization powder making method

[0056] 3 , a method for preparing metal or alloy powder using the aforementioned vacuum consumable arc melting ultrasonic atomization powder making system of the present invention is exemplarily provided, comprising the following steps:

[0057] One end of the metal or alloy bar is connected and fixed to the clamping and conductive device as the electrode bar, and the other end of the metal or alloy bar is positioned directly above the smelting device as the working end surface;

[0058] The vacuum chamber is sealed and evacuated until it reaches the first pressure range. If the metal or alloy bar contains volatile elements, the vacuum chamber is controlled to be within the second pressure range by adding inert gas, and the circulating water cooling system in the side wall of the vacuum chamber is started to maintain the side wall of the vacuum chamber within the required temperature range.

[0059] The clamping and conductive devices are driven to drive the electrode bar to descend until the required distance between the electrode bar and the melting device is reached. Then, the power supply device and the ultrasonic generator are started according to the output power of the power supply device and the frequency of the ultrasonic generator set by the preset parameters to complete arc initiation and generate ultrasonic waves.

[0060] Adjust the parameters according to the preset process and actual effect, and start powder making after confirming that the arc state and the molten pool page state are normal;

[0061] Among them, the electrode rod is used as the cathode and the smelting device is used as the anode. After the power is turned on and the arc is struck, the working end face of the electrode rod is heated and gradually melted, and continuously drips into the smelting device. The arc between the cathode and anode continuously heats the melt in the smelting device and forms a molten pool. The molten liquid in the molten pool is broken by the ultrasonic impact, and the formed droplets splash or flow to the outside of the smelting device and contact the side wall of the vacuum chamber, cooling and solidifying to form metal or alloy particles.

[0062] As an optional embodiment, the first pressure range is not higher than 6.5×10 -2 Pa.

[0063] As an optional embodiment, the second pressure range is 1×10 4 Pa~4×10 4 Pa.

[0064] As an optional implementation, the electrode rod material descends at a speed between 5 mm / min and 100 mm / min.

[0065] As an optional embodiment, the electrode rod is lowered until the distance between the electrode rod and the smelting device reaches 30 mm to 50 mm.

[0066] As an optional implementation, the output power of the power supply device is adjusted by controlling the current, which is between 500A and 3500A.

[0067] As an optional embodiment, the initial frequency of the ultrasonic generating device is between 5kHz and 15kHz, and the frequency during the stable powder making process is between 20kHz and 60kHz.

[0068] As an optional embodiment, the diameter of the electrode rod material is between 5 mm and 150 mm, and the length is between 200 mm and 2500 mm.

[0069] In one specific embodiment, the vacuum consumable arc melting ultrasonic atomization powder making method includes the following specific steps:

[0070] 1) Raw material preparation: The raw materials used in this method are metal or alloy rods with a diameter ranging from 5 mm to 150 mm and a length of 200 mm to 2500 mm. The raw material rods are placed in the electrode position, directly above the melting crucible, and an ultrasonic generating system is installed below the melting crucible.

[0071] The raw material can be a prefabricated master alloy rod, or an electrode rod made by mixing single materials and pressing alloy waste.

[0072] 2) Atmosphere and temperature guarantee: vacuum the powder making system, with the target vacuum degree being 6.5×10 -2 Pa, if the alloy material contains volatile elements, it can be filled with inert gas, such as argon with a purity of not less than 99.99%. The pressure after filling is between 1×10 4 Pa~4×10 4 Pa; and ensure that the outlet temperature of the circulating water on the side wall of the vacuum chamber is lower than 40°C.

[0073] 3) Start ultrasound: Start the ultrasonic generating system to generate high-frequency ultrasonic waves and transmit them to the melting crucible;

[0074] Among them, the initial frequency of the ultrasonic generating device is between 5kHz and 15kHz, and the frequency during the stable powder making process is between 20kHz and 60kHz.

[0075] 4) Consumable arc melting: The raw material rod is used as the cathode and the melting device (e.g., crucible) is used as the anode. After the arc is ignited, the end of the rod is heated and gradually melts, and continuously drips into the melting crucible. The arc between the cathode and anode continuously heats the melt in the crucible and forms a shallow molten pool.

[0076] The specific process is as follows: the electrode bar material falls vertically downward under the drive of the clamping and conductive device, and the descending speed is between 5mm / min and 100mm / min. When the distance between the end of the electrode bar material and the upper surface of the melting device is between 30mm and 50mm, the power supply is started and the arc is struck. The descending speed of the electrode bar material and the output power of the power supply are controlled. Under the thermal effect of the arc, the electrode bar material begins to melt, and the molten droplets fall into the melting device below and are further heated by the arc to achieve refining. The output power of the power supply is adjusted by controlling the current size, which is between 500A and 3500A.

[0077] 5) Ultrasonic atomization: The molten metal in the smelting device is broken by the impact of high-frequency sound waves, forming tiny droplets or even mist, which splash or flow to the outside of the crucible and cool and solidify to form metal or alloy particles;

[0078] The specific process is as follows: the ultrasonic generator system generates directional sound waves that pass through the crucible to the molten pool and stimulate the droplet jet. After the droplets leave the molten pool, they are further refined, cooled, and solidified to form metal or alloy powder;

[0079] By adjusting the ultrasonic frequency and duration, the droplet sputtering rate is controlled, and the arc flame length, melting rate, molten pool depth and temperature are maintained stable by coordinating the electrode bar material descent rate and melting power.

[0080] There are two ultrasonic operation modes. For conventional materials, continuous operation is adopted, in which ultrasonic atomization is performed continuously while melting. For refractory materials, intermittent ultrasonic operation is adopted to allow the melt sufficient time to heat up.

[0081] By controlling the ultrasonic frequency and operation mode, the droplet sputtering rate and droplet size in the molten pool can be adjusted to ensure that the maximum sputtering rate does not exceed 100cm 3 / min.

[0082] The arc flame length affects the heat output of the arc. The melting rate of the electrode bar, that is, the rate at which new melt is added to the molten pool, can be adjusted by coordinating the descending speed of the electrode bar. By matching the melting rate and sputtering rate, the stability of the molten pool depth and temperature is maintained, thereby ensuring the stability of the yield and particle characteristics (morphology and size) of the ultrasonic atomization powder making process.

[0083] 6) Powder collection: Under the action of airflow or gravity, the powder is separated or settled from the exhaust port to the bottom collection device.

[0084] The vacuum consumable arc melting ultrasonic atomization powder making method of the present invention uses a metal or alloy rod as a cathode, forms a micro-melting pool through consumable arc remelting, and uses ultrasonic waves as the energy source for atomization powder making. Under the action of ultrasonic waves, the liquid metal or alloy produces sputtering or forms metal mist, and powder is made in a vacuum environment. While avoiding the problems of hollow powder and satellite powder easily produced in the atomization process, powder particles with high sphericity (≥0.95), high density (≥99%) and narrow particle size distribution (≤60μm) are obtained, which meets the powder requirements of powder near-net forming technologies such as additive manufacturing and powder metallurgy, solves the problem that the preparation of metal powder by ultrasonic atomization is limited to the low melting point metal range, and realizes the preparation of high melting point and even refractory metal and alloy powders.

[0085] The technical solution of the present invention will be further described below in conjunction with the process flow chart and preparation system diagram of the present invention, taking TC4 titanium alloy powder material as an example.

[0086] The composition of TC4 powder is Al: 6.03%, V: 4.11%, Fe: 0.065%, O: 0.1259%, N: 0.0076%, H: 0.0007%, C: 0.0025%, Ti: bal.

[0087] Example 1

[0088] First, the TC4 prefabricated electrode rod 310 with a diameter of 50mm and a length of 2000mm is fixed to the clamping and conductive device 110 so that the electrode rod 310 is located directly above the smelting device 320. After the system is sealed, the powder making system is vacuumed through the first channel 210 to reach the target vacuum degree of 6.5*10 -2 Pa, and high-purity argon is added through the second channel 220 until the system pressure is 3*10 4 Pa, argon purity is 99.999%.

[0089] The electrode bar 310 was lowered at a speed of 25 mm / min, and the ultrasonic generator 330 was activated at a frequency of 10 kHz. When the distance between the electrode bar and the melting device was 40 mm, the power supply was activated and the current was set to 1400 A. Under the heat of the arc, the end of the electrode bar gradually melted, forming a molten pool.

[0090] According to the preset process and actual results, the atomization powder making process parameters were set, including the current intensity of 1600A, the bar feed speed of 27mm / min, and the ultrasonic frequency of 40kHz and maintained. The state of the arc 4 and the liquid level of the molten pool 5 were observed and confirmed to be normal.

[0091] During the stable powder making process, the end of the TC4 electrode rod fed at a low speed is continuously melted by the arc and added to the molten pool. Under the action of ultrasound, the molten liquid in the molten pool is sputtered to produce droplets. The droplets contact the cooling wall during flight, pass through the lower cone section, and fall into the powder collecting tank to obtain TC4 titanium alloy powder.

[0092] The obtained powder was passed through a 100-mesh sieve to obtain the target segment powder, and the particle size and shape were tested, and the density of the cross section was observed.

[0093] After testing, the D50 of the powder was 76.92 μm, the particle size distribution (D84-D16) was 47.8 μm, the sphericity was 0.96, and the density reached 99.5%.

[0094] The fewer pores on the particle interface, the higher the density, indicating less hollow powder; the higher the powder sphericity, the closer the powder morphology is to a perfect sphere (sphericity 1.0). Therefore, the above preparation process effectively avoids the problems of hollow powder and satellite powder that are easily produced under the aerosolization process.

[0095] Therefore, the metal powder prepared by the vacuum consumable arc melting ultrasonic atomization powder making system of the present invention has high sphericity (≥0.95), high density (≥99%), and narrow particle size distribution (≤60μm), which meets the powder requirements of powder near-net forming technologies such as additive manufacturing and powder metallurgy, and can effectively avoid the defects such as hollow powder and satellite powder that are easily produced by the atomization process, solve the problem that the preparation of metal powder by ultrasonic atomization is limited to the range of low melting point metals, and realize the preparation of high melting point and even refractory metal and alloy powders.

[0096] While the present invention has been disclosed above with reference to preferred embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A vacuum consumable arc melting ultrasonic atomization powder making system, characterized in that: include: The transmission and conducting system (100) is provided with a clamping and conducting device (110), wherein a first end of the clamping and conducting device (110) is connected to a driving device and a power supply device, and is used to provide feeding power and electric energy for the clamping and conducting device; A vacuum chamber (200), wherein a first channel (210) and a second channel (220) are provided on a side wall of the vacuum chamber (200), the vacuum chamber (200) is evacuated through the first channel (210), and the vacuum chamber (200) is replenished with gas through the second channel (220), so that the vacuum chamber reaches a required pressure condition; A circulating water cooling system is provided inside the side wall surface of the vacuum chamber (200), and the side wall surface of the vacuum chamber is maintained at a cooling temperature required for powder making through the circulating water cooling system; The upper end surface of the vacuum chamber (200) is provided with a through hole, and the second end of the clamping and conducting device (110) passes through the through hole and is connected to the powder making system (300) provided in the vacuum chamber; The powder making system (300) comprises an electrode bar (310), a smelting device (320) and an ultrasonic generating device (330); the electrode bar (310) is connected and fixed to the second end of the clamping and conducting device (110) so that the working end surface of the electrode bar (310) is located directly above the smelting device (320); and the ultrasonic generating device (330) is provided below the smelting device (320); The electrode rod (310) is driven down by the clamping and conducting device (110), and an arc (340) is generated between the electrode rod (310) and the smelting device (320) by electric energy, so that the working end surface of the electrode rod (310) is melted, and a molten pool (350) is generated in the smelting device (320). Under the action of the ultrasonic generating device (330), the molten liquid in the molten pool (350) is broken by the ultrasonic wave and sputtered out to generate droplets (360). The droplets (360) are cooled by contact with the side wall of the vacuum chamber, solidified to form metal or alloy particles (500), and fall into the powder collecting device (400) connected to the lower end surface of the vacuum chamber for collection.

2. The vacuum consumable arc melting ultrasonic atomization powder making system according to claim 1 is characterized in that: The lower end of the vacuum chamber (200) is configured as a cone that is larger at the top and smaller at the bottom, and the lower part of the cone is connected to the powder collecting device (400).

3. The vacuum consumable arc melting ultrasonic atomization powder making system according to claim 2 is characterized in that: The second channel (220) is arranged on the wall surface of the vertebral body.

4. The vacuum consumable arc melting ultrasonic atomization powder making system according to claim 1, characterized in that: A sealing device is provided at the through hole where the second end of the clamping and conducting device (110) enters the vacuum chamber.

5. A method for preparing metal or alloy powder using the vacuum consumable arc melting ultrasonic atomization powder making system according to any one of claims 1 to 4, characterized in that: The following steps are involved: One end of the metal or alloy bar is connected and fixed to the clamping and conducting device as an electrode bar, and the other end of the metal or alloy bar is located directly above the smelting device as a working end surface; The vacuum chamber is sealed and evacuated until it reaches the first pressure range. If the metal or alloy bar contains volatile elements, If the vacuum chamber is in a second pressure range, the inert gas is added to control the vacuum chamber to be within the second pressure range, and the circulating water cooling system in the side wall of the vacuum chamber is started to maintain the side wall of the vacuum chamber within the required temperature range; The clamping and conducting device is driven to drive the electrode bar material to descend until the required distance between the electrode bar material and the smelting device is reached, and then the power supply device and the ultrasonic generating device are started according to the output power of the power supply device and the frequency of the ultrasonic generating device set by the preset parameters to complete arc initiation and generate ultrasonic waves; Adjust the parameters according to the preset process and actual effect, and start powder making after confirming that the arc state and the molten pool page state are normal; Among them, the electrode rod is used as the cathode and the smelting device is used as the anode. After the power is turned on and the arc is struck, the working end face of the electrode rod is heated and gradually melted, and continuously drips into the smelting device. The arc between the cathode and the anode continuously heats the melt in the smelting device to form a molten pool. The molten liquid in the molten pool is broken by the ultrasonic impact, and the formed droplets splash or flow to the outside of the smelting device and contact the side wall of the vacuum chamber, and then cool and solidify to form metal or alloy particles.

6. The method according to claim 5, characterized in that The first pressure range is not higher than 6.5×10 -2 Pa, the second pressure range is 1×10 4 Pa~4×10 4 Pa.

7. The method according to claim 5, characterized in that The temperature of the vacuum chamber wall is maintained below 40°C.

8. The method according to claim 5, characterized in that The electrode rod material descends at a speed between 5 mm / min and 100 mm / min, and the electrode rod material descends until the distance between the electrode rod material and the smelting device reaches between 30 mm and 50 mm.

9. The method according to claim 5, characterized in that The output power of the power supply device is adjusted by controlling the current size, which is between 500A and 3500A; the initial frequency of the ultrasonic generating device is between 5kHz and 15kHz, and the frequency during the stable powder making process is between 20kHz and 60kHz.

10. The method according to claim 5, characterized in that The electrode rod material has a diameter of 5 mm to 150 mm and a length of 200 mm to 2500 mm.

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