Gas output control device, gas atomizing pulverizing device and pulverizing method

Abstract

The present disclosure relates to a gas output control device, a gas atomization powder production device and a powder production method, wherein the gas output control device comprises a gas cylinder, a pressure regulating valve, a pressure gauge, an adjusting track, a fixing device and a gas nozzle, the gas cylinder is communicated with the gas nozzle through a gas path, the nozzle is used for spraying the gas into the atomization chamber, the pressure regulating valve is arranged at the output end of the gas cylinder for controlling the gas pressure, the fixing device is arranged on the adjusting track and is in sliding connection with the adjusting track, the fixing device is used for connecting with the gas nozzle and adjusting the distance and the inclination angle of the gas nozzle. The present disclosure can avoid that the satellite powder accounts for a large proportion.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of gas atomization powder production, in particular, to a gas output control device, a gas atomization powder production device and a powder production method. BACKGROUND

[0002] Gas atomization powder production technology is to break high-temperature metal liquid through the interaction between gas and liquid, so as to form fine liquid droplets, and then solidify to form metal powder particles. The gas atomization powder production process can efficiently and at low cost produce high-quality powder, which can be used in various process occasions, and has a very broad application prospect in the field of additive manufacturing.

[0003] In the prior art, when the secondary atomization process starts, the velocity difference between the gas and the liquid droplets is very large, and the liquid droplets will be immediately broken down. As the large liquid droplets are broken into many small liquid droplets, the velocities of these liquid droplets are different. Generally speaking, the smaller the liquid droplet size, the faster the liquid droplet velocity, and smaller liquid droplets will catch larger liquid droplets and adhere to their surfaces; in addition, smaller liquid droplets cool faster than larger liquid droplets, so smaller liquid droplets with lower temperature can collide with larger liquid droplets and adhere to them, and eventually solidify into satellite powder.

[0004] Satellite powder will affect the flowability and density of the powder, and has an adverse effect on the additive manufacturing process, which will lead to an increase in defects such as pores and cracks in the workpiece, and a decrease in the quality of the workpiece, which cannot meet the needs of actual use. SUMMARY

[0005] The purpose of the present disclosure is to provide a gas output control device, a gas atomization powder production device and a powder production method, which can avoid a high proportion of satellite powder. In order to achieve the above purpose, the present disclosure provides a gas output control device, which comprises a gas cylinder, a pressure regulating valve, a pressure gauge, an adjusting track, a fixing device and a gas nozzle, the gas cylinder is communicated with the gas nozzle through a gas path, the nozzle is used for spraying the gas into the atomization chamber, the pressure regulating valve is arranged at the output end of the gas cylinder for controlling the gas pressure, the fixing device is arranged on the adjusting track and is in sliding connection with the adjusting track, the fixing device is used for connecting with the gas nozzle and adjusting the distance and the inclination angle of the gas nozzle. Optionally, the fixing device comprises a fixing block and a connecting piece, the fixing block is fixedly connected with the gas nozzle, the fixing block is hinged with the adjusting track through the connecting piece, the connecting piece is perpendicular to the pivot axis of the adjusting track, and the connecting piece is in sliding connection with the adjusting track.

[0006] Optionally, the adjusting track and the fixing device are located inside the atomization chamber.

[0007] Optionally, the gas output control device further comprises a control system for controlling the position and inclination angle of the fixing device, which can be configured as an electric control system electrically connected with the fixing device.

[0008] Optionally, the gas output control device comprises a plurality of fixing devices and gas nozzles, and the plurality of fixing devices are electrically connected with the electric control system and move synchronously.

[0009] In another aspect, the present disclosure provides a gas atomization powder production device, which comprises a metal melt output device, a gas atomization device and a gas output control device as described above.

[0010] Optionally, the metal melt output device comprises an induction furnace, an induction furnace control system and a metal melt nozzle; the induction furnace is used for melting metal raw materials, and the metal melt nozzle is in communication with the induction furnace; the gas atomization device comprises an atomization chamber and a collector; the lower end of the atomization chamber is provided with a discharge port, and the discharge port is in communication with the collector.

[0011] In still another aspect, the present disclosure provides a powder production method, which comprises the following steps:

[0012] Step one: establishing a simulation model of gas-liquid interaction crushing process according to material parameters, and establishing a crushing phase diagram of the selected material according to the simulation results;

[0013] Step two: establishing a finite element model of the gas atomization powder production process according to process parameters and equipment parameters, performing simulation, obtaining the velocity field distribution of the droplets and the dimensionless number condition;

[0014] Step three: formulating optimized equipment parameters and process parameters according to the crushing phase diagram, the velocity field distribution and the dimensionless number distribution, using the optimized parameters for the gas atomization powder production process, and performing satellite powder proportion analysis on the produced samples;

[0015] Step four: if the satellite powder proportion meets the requirements, recording the optimized parameters as alternatives; if the satellite powder proportion does not meet the requirements, resetting the related parameters and repeating steps two to three;

[0016] Step five: repeating step four, and obtaining the most suitable equipment and process parameters for actual production, i.e. performing the gas atomization powder production process according to the equipment and process parameters, so that the satellite powder proportion in the obtained powder is most suitable for subsequent production;

[0017] Step six: adjusting the corresponding parameters of the equipment to perform the gas atomization powder production process.

[0018] Optionally, the equipment parameters in step three comprise the distance between the gas nozzles, the inclination angle of the gas nozzles, and the wall material and geometric structure parameters of the atomization chamber (30-1).

[0019] Optionally, the material parameters of step one include the composition elements of the metal material, the content of each element, and the melting point of each element and the relationship between the boiling point of each element and the pressure and temperature.

[0020] Optionally, the process parameters of step two include the initial velocity of the metal liquid at the nozzle outlet, the initial temperature of the metal liquid, the gas pressure at the gas gate, the incident angle of the gas gate, and the spacing of the gas gate.

[0021] Optionally, the simulation model of step one should be able to calculate the gas-liquid multiphase flow interaction process.

[0022] Optionally, the finite element model of step two is used to calculate the physical processes involved in actual gas atomization, including heat transfer process, mass transfer process, solidification process, turbulent flow process and gas-liquid multiphase flow interaction process, wherein the grid size of the finite element model is smaller than the minimum powder particle size. Optionally, the step two further comprises modifying the finite element model to meet the actual physical process and accuracy requirements as the process parameters and material parameters change.

[0023] Optionally, the finite element model calculates the gas atomization physical process for a time greater than or equal to 1s.

[0024] Optionally, the metal material includes titanium alloy, aluminum alloy, iron alloy or composite material.

[0025] Optionally, the method for analyzing the proportion of satellite powder is selected from one or more of CT, SEM and STEM.

[0026] Through the above technical solution, when the output of the gas needs to be controlled, the fixed device is adjusted, the fixed device moves on the track, thereby changing the position of the gas nozzle, changing the spacing between the gas nozzles, rotating the fixed device, thereby changing the inclination angle of the gas nozzle, changing the speed difference of the gas in the atomization process by changing the spacing and inclination angle between the gas nozzles, reducing the decomposition of liquid droplets into small liquid droplets, and reducing the collision of large and small liquid droplets to form satellite powder.

[0027] Other features and advantages of the present disclosure will be described in detail in the following detailed description section. BRIEF DESCRIPTION OF DRAWINGS

[0028] The accompanying drawings are included to provide a further understanding of the present disclosure and constitute a part of the specification, and are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation on the present disclosure. In the drawings:

[0029] Figure 1 Optimized gas atomization device structure schematic diagram;

[0030] Figure 2 Method flow for reducing satellite powder using optimized gas atomization equipment

[0031] Figure 3 Schematic diagram of gas atomization powder production process equipment structure and calculation domain

[0032] Figure 4 Droplet breakup map for metal materials.

[0033] Explanation of reference signs

[0034] 10, gas output control device; 10-1, gas cylinder; 10-2, pressure regulating valve; 10-3, pressure gauge; 10-4, adjusting track; 10-5, fixing device; 20, metal melt output device; 20-1, induction furnace; 20-2, induction furnace control system; 20-3, metal melt nozzle; 30, gas atomization equipment; 30-1, atomization chamber; 30-2, collector. DETAILED DESCRIPTION

[0035] The specific embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely intended to illustrate and explain the present disclosure, and are not intended to limit the present disclosure.

[0036] In the present disclosure, the orientation words such as "inner" and "outer" are relative to the "inner" and "outer" of the corresponding component itself profile, unless otherwise stated. In addition, the terms "first", "second", etc. used in the present disclosure are used to distinguish one element from another element, and do not have sequentiality and importance. In addition, in the following description, the same reference signs in different drawings represent the same or similar elements, unless otherwise explained. The above definitions are only used to explain and illustrate the present disclosure, and should not be understood as limiting the present disclosure. The present embodiment provides a gas output control device 10, which includes a gas cylinder 10-1, a pressure regulating valve 10-2, a pressure gauge 10-3, an adjusting track 10-4, a fixing device 10-5, and a gas nozzle. The gas cylinder 10-1 is in communication with the gas nozzle through a gas path, the nozzle is used to spray gas into the atomization chamber 30-1, the pressure regulating valve 10-2 is arranged at the output end of the gas cylinder 10-1 for controlling the gas pressure, the fixing device 10-5 is arranged on the adjusting track and is in sliding connection with the adjusting track, and the fixing device 10-5 is used to connect with the gas nozzle and adjust the distance and inclination angle of the gas nozzle.

[0037] By the above technical scheme, when the output of the gas needs to be controlled, the fixed device 10-5 is adjusted, the fixed device 10-5 moves on the track, thereby changing the position of the gas nozzle, changing the distance between the gas nozzles, rotating the fixed device 10-5, thereby changing the inclination angle of the gas nozzle, changing the distance between the gas nozzles and the inclination angle, thereby changing the speed difference of the gas in the atomization process, reducing the decomposition of liquid droplets into small liquid droplets, and reducing the collision of large and small liquid droplets to form satellite powder.

[0038] As an optional embodiment, the fixed device 10-5 includes a fixed block and a connecting piece, the fixed block is fixedly connected with the gas nozzle, the fixed block is hinged with the adjusting track 10-4 through the connecting piece, the connecting piece is perpendicular to the pivot axis of the adjusting track 10-4, and the connecting piece is slidingly connected with the adjusting track 10-4. In the process of adjusting the gas nozzle, the fixed block is pushed, the connecting piece moves on the adjusting track 10-4, thereby changing the position of the fixed block and the gas nozzle, changing the distance between the gas nozzles, and adjusting the angle of the gas nozzle when needed, pushing the fixed block to change the angle of the connecting piece, thereby changing the inclination angle of the gas nozzle.

[0039] As an optional embodiment, the adjusting track 10-4 and the fixed device 10-5 are located inside the atomization chamber 30-1. The gas tightness inside the atomization chamber 30-1 is maintained, and the overflow of the gas is reduced.

[0040] As an optional embodiment, the gas output control device 10 further includes a control system for controlling the position and inclination angle of the fixed device 10-5, the control system can be configured as an electric control system, and the electric control system is electrically connected with the fixed device 10-5. The position and inclination angle of the fixed device 10-5 can be controlled in real time by the external electric control system, thereby controlling the inclination angle and distance between the gas nozzles.

[0041] As an optional embodiment, the gas output control device 10 includes a plurality of fixed devices 10-5 and gas nozzles, the plurality of fixed devices 10-5 are electrically connected with the electric control system and move synchronously. The inclination angle of the gas nozzle and the distance between the nozzle position and the center line of the metal melt nozzle 20-3 are ensured to be the same by synchronous movement

[0042] On the other hand, the present disclosure provides a gas atomization powder making equipment, which includes a metal melt output device 20, a gas atomization device 30, and a gas output control device 10 as above. The metal melt output device 20 melts the metal, outputs the gas through the gas output device, and the atomization chamber 30-1 performs the atomization process, thereby completing the gas atomization powder making to condense the small metal liquid droplets into powder.

[0043] As an optional implementation, the metal melt output device 20 comprises an induction furnace 20-1, an induction furnace control system 20-2, and a metal melt nozzle 20-3; the induction furnace 20-1 is used for melting the metal raw material, and the metal melt nozzle 20-3 is in communication with the induction furnace 20-1; the gas atomization device 30 comprises an atomization chamber 30-1 and a collector 30-2; the atomization chamber 30-1 is provided with a discharge port at the lower end, and the discharge port is in communication with the collector 30-2. After the metal raw material is added to the induction furnace 20-1, a melting process occurs in the furnace, and then the metal melt passes through the metal melt nozzle 20-3 below and enters the atomization chamber 30-1. Through the metal melt output device 20, the metal can be converted into a molten metal material, which is ready for gas atomization.

[0044] In another aspect, the present disclosure provides a powder production method, comprising the following steps: step one: establishing a gas-liquid interaction crushing process simulation model according to material parameters, and establishing a crushing phase diagram of the selected material according to the simulation results; step two: establishing a gas atomization powder production process finite element model according to process parameters and equipment parameters, performing simulation, and obtaining the velocity field distribution of the liquid droplets and the dimensionless number distribution; step three: formulating optimized equipment parameters and process parameters according to the crushing phase diagram, the velocity field distribution, and the dimensionless number distribution, using the optimized parameters for the gas atomization powder production process, and performing satellite powder proportion analysis on the produced samples; step four: if the satellite powder proportion meets the requirements, the optimized parameters are recorded as candidates; if the satellite powder proportion does not meet the requirements, the related parameters are reset, and steps two to three are repeated; step five: repeating step four, and obtaining the most suitable equipment and process parameters for actual production according to the actual situation; step six: adjusting the corresponding parameters of the equipment for the gas atomization powder production process.

[0045] As an optional implementation, the equipment parameters in step three include the spacing of the gas nozzles, the inclination angle of the gas nozzles, and the wall material and geometric structure parameters of the atomization chamber 30-1.

[0046] As an optional implementation, the material parameters in step one include the constituent elements of the metal material added to the gas atomization powder production equipment, the content of each element, and the relationship between the melting point of each element and the pressure and temperature of the boiling point of each element.

[0047] As an optional implementation, the process parameters in step one include the initial velocity of the metal liquid at the nozzle outlet, the initial temperature of the metal liquid, the gas pressure at the gas gate, the incidence angle of the gas gate, and the spacing of the gas gate.

[0048] As an optional implementation, the simulation model in step one should be able to calculate the gas-liquid multiphase flow interaction process.

[0049] As an optional embodiment, the finite element model of step two is used to calculate the physical process involved in the actual gas atomization, including heat transfer process, mass transfer process, solidification process, turbulent flow process and gas-liquid multiphase flow interaction process, wherein the grid size of the finite element model is smaller than the minimum powder particle size.

[0050] As an optional embodiment, step two further comprises modifying the finite element model to meet the actual physical process and accuracy requirements as the process parameters and material parameters change.

[0051] As an optional embodiment, the time length of the finite element model to calculate the gas atomization physical process is greater than or equal to 1s.

[0052] As an optional embodiment, the metal material includes titanium alloy, aluminum alloy, iron alloy or composite material.

[0053] As an optional embodiment, the method for analyzing the satellite powder ratio is selected from one or more of CT, SEM and STEM. According to the above-mentioned powdering method, an embodiment of preparing AlSi10Mg metal powder from TiB2-based AlSi10Mg composite metal material is provided:

[0054] Step one: according to the average flow velocity of each physical parameter of TiB2-based AlSi10Mg composite metal material and different fluid phases as shown in Table 1, a gas-liquid interaction breaking process simulation model is established, and a breaking phase diagram of TiB2-based AlSi10Mg composite metal material is established according to the simulation results;

[0055] Table 1 Physical parameters of TiB2-based AlSi10Mg composite metal material

[0056] Metal fluid density Viscosity Surface tension 2.44 g / cm3 1.14 g / m-s 865 nN / mm 3 ]]>

[0057] Step two: a finite element model of gas atomization powdering process is established according to the process parameters and equipment parameters, simulation is performed, and the velocity field distribution of liquid droplets and the non-dimensional number Weber number and Oh number are obtained;

[0058] The wall material and nozzle material of the gas atomization powdering process equipment are stainless steel, the nozzle geometric structure parameters, the geometric structure parameters of the gas valve and the respective geometric position relationship are as shown in Figure 1

[0059] The process parameters are shown in Table 2:

[0060] Table 2 Gas atomization powdering process parameters

[0061] Initial velocity of the metal liquid V Temperature of the metal liquid T1 Gas pressure P Gas temperature T2 5 m / s 1050K 0.2 MPa 300K

[0062] ​Step three: the broken phase diagram of the TiB2-based AlSi10Mg composite metal material obtained in step one is combined with the velocity field distribution obtained in step two and the dimensionless number, and the optimized equipment and process parameters are formulated, and the gas atomization powder production process is carried out using the optimized equipment and process parameters, and the powder defect analysis is carried out on the produced sample;

[0063] Step four: if the defect proportion of the AlSi10Mg metal powder meets the requirements, the optimized production parameters are recorded as alternatives; if the defect proportion of the AlSi10Mg metal powder does not meet the requirements, the related parameters are reset, and steps two to three are repeated;

[0064] Step five: step four is repeated, and the most suitable equipment and process parameters for actual production are obtained by combining the production conditions and requirements;

[0065] Step six: the fixing device of the equipment is adjusted, each parameter is set to the optimized equipment and process parameters obtained in step five, the gas atomization powder production process is carried out, and the satellite powder proportion in the obtained powder is low.

[0066] The preferred embodiments of the present disclosure are described in detail above in combination with the drawings, but the present disclosure is not limited to the specific details in the above-described embodiments. Within the technical concept range of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all belong to the protection range of the present disclosure.

[0067] In addition, it should be noted that each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, various possible combination manners are not described again in the present disclosure. In addition, various different embodiments of the present disclosure can also be combined in any manner, as long as it does not deviate from the idea of the present disclosure, and it should be considered as the disclosed content of the present disclosure.

Claims

1. A flour making method, characterized in that: The following steps are involved: Step 1: Establish a simulation model of the gas-liquid interaction crushing process based on the material parameters, and establish a crushing phase diagram of the selected material based on the simulation results; Step 2: Establish a finite element model of the aerosol powder making process based on the process parameters and equipment parameters, perform simulations, and obtain the velocity field distribution and dimensionless number of the droplets; Step 3: Develop optimized equipment parameters and process parameters based on the crushing phase diagram, velocity field distribution, and dimensionless number distribution. Use the optimized equipment parameters and process parameters to carry out the aerosol powder production process, and perform satellite powder ratio analysis on the produced samples. Step 4: If the satellite powder ratio meets the requirements, record the optimized equipment parameters and process parameters as alternatives; if the powder defect ratio does not meet the requirements, reset the relevant parameters and repeat steps 2 to 3; Step 5: Repeat step 4, comprehensively considering the actual situation, and obtain the equipment and process parameters that are most suitable for actual production. That is, the aerosol powder making process is carried out according to this equipment and process parameters, and the proportion of satellite powder in the obtained powder is most suitable for subsequent production; Step six: Adjust the corresponding parameters of the equipment to carry out the aerosol powder production process; the equipment parameters in the step three include the spacing of the gas nozzles, the inclination angle of the gas nozzles, and the wall material and geometric structure parameters of the atomization chamber; the material parameters described in step one include the constituent elements of the metal material added to the aerosol powder production process equipment, the content of each element, and the relationship between the melting point of each element and the boiling point of each element and the pressure and temperature; the process parameters described in step two include the initial velocity of the molten metal at the nozzle outlet, the initial temperature of the molten metal, the gas pressure at the valve, the incident angle of the valve and the spacing of the valve; the simulation model described in step one can calculate the gas-liquid multiphase flow interaction process; the finite element model described in step two is used to calculate the physical processes involved in actual aerosolization, including heat transfer process, mass transfer process, solidification process, turbulence process and gas-liquid multiphase flow interaction process, wherein the grid size of the finite element model is smaller than the minimum powder particle size.

2. The flour making method according to claim 1, wherein The second step also includes modifying the finite element model as the process parameters and material parameters change to meet the actual physical process and accuracy requirements.

3. The flour making method according to claim 2, wherein The time length of the finite element model calculation of the aerosolization physical process is greater than or equal to 1s.

4. The flour making method according to claim 3, characterized in that Metal materials include titanium alloys, aluminum alloys, iron alloys or composite materials.

5. The flour making method according to claim 3, characterized in that The method for analyzing the proportion of satellite powder is selected from one or more of CT, SEM and STEM.

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