Powder treatment device and method for improving sphericity and surface smoothness of powder

Abstract

The invention relates to a powder processing device and method for improving sphericity and surface smoothness of powder, the powder processing device comprises a processing cylinder and a plurality of rotating mechanisms, the lower rotating mechanism comprises stirring blades and can rotate in the forward direction, and the upper rotating mechanism comprises shaping blades and can rotate in the forward direction or in the reverse direction. A certain obtuse angle is formed between a stirring blade of the lower rotating mechanism and the rotating direction, powder can be raised better, and a shaping blade of the upper rotating mechanism comprises a positive inclined plane and a negative inclined plane. Firstly, the rotating directions of the upper rotating mechanism and the lower rotating mechanism are opposite, the inclined faces, facing the rotating direction, of the shaping blades are opposite to the moving direction of raised powder, the angles of the inclined faces are approximately perpendicular to the moving direction of the raised powder, and agglomerated powder and satellite balls are impacted and crushed; the rotating directions of the upper rotating mechanism and the lower rotating mechanism are identical, and the inclined faces, facing the rotating direction, of the shaping blades are close to the moving direction of the raised powder; and the surface smoothness of the powder is improved mainly by friction action. The stirring blades of the lower rotating mechanism enable the powder particles in the barrel to generate a friction effect, and the surface smoothness of the powder can also be rapidly improved.

Description

Technical Field

[0001] The invention relates to the technical field of metal powder preparation, and in particular to a powder processing device and method for improving the sphericity and surface smoothness of powder. Background Art

[0002] In recent years, metal powder additive manufacturing (AM) and injection molding (MIM) technologies have developed rapidly. Both can meet the rapid manufacturing of complex structural parts, but at the same time, higher requirements are also placed on the morphology of metal powder raw materials. The metal powder prepared by the VIGA gas atomization process has a relatively high sphericity and can be used as the raw material for metal powder additive manufacturing. However, the manufactured powder often contains a certain number of satellite balls, agglomerated powders and irregular powders, which leads to the deterioration of the powder sphericity, the decrease of bulk density and fluidity, and the comprehensive performance of the powder is not as good as that of products prepared by processes such as PREP. The metal powder prepared by water atomization or water-gas combined atomization has relatively poor powder sphericity and can generally be used as the raw material for metal powder injection molding. However, due to the presence of a large amount of irregular powder, agglomerated powder or satellite balls, the powder tap density decreases, and the loading capacity and rheological properties after feeding are limited, which affects the injection molding performance and the further improvement of the density and mechanical properties of the parts after sintering.

[0003] For the preparation of high-quality powders, in addition to improving the powder morphology by improving the atomization process, the powder processing preparation process can also be improved. Traditional post-processing methods mainly include two types of methods: crushing and grinding. The use of powder crushing technology and equipment (such as toothed disc crushing) can break the agglomerated powder into independent small particles, and separate the satellite balls from the surface of large particle powders to improve the sphericity of the powder. However, after crushing, the powder surface shows obvious edges and corners, and the roughness of the powder surface increases significantly, which is not conducive to the improvement of indicators such as powder loose packing, tap density, and fluidity. The use of powder grinding technology and equipment (such as air flow mills) can eliminate the edges and corners of the powder surface to a certain extent and improve the surface finish of the powder. However, due to limited force and energy, the crushing effect and efficiency of agglomerated powder and satellite balls are significantly reduced. Therefore, how to efficiently improve the sphericity and surface finish of the powder at the same time is a difficult problem in powder processing. Summary of the invention

[0004] The purpose of the present invention is to provide a powder processing device and method for improving the sphericity and surface smoothness of powder, so as to solve the problem that traditional powder processing processes are difficult to simultaneously and efficiently crush agglomerated powder and satellite spheres and improve the surface smoothness of powder. It can effectively improve the morphology level of metal powder materials, as well as comprehensive properties such as loose density, tap density, and fluidity, and improve the applicability of gas atomization and water atomization powder raw materials in the fields of additive manufacturing and injection molding.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: A powder processing device for improving the sphericity and surface smoothness of powder, comprising a powder processing barrel and a plurality of rotating mechanisms installed inside, wherein a feeding port and a valve are provided at the top of the powder processing barrel, and a feeding port and a valve are provided at the bottom, and the rotating stirring mechanism can be divided into an upper rotating mechanism and a lower rotating mechanism, wherein the lower rotating mechanism comprises two or more stirring blades, and a central rotating shaft is connected to a driving motor outside the powder processing barrel, and can rotate at a high speed driven by the driving motor, and its rotation direction is defined as forward rotation, and there is a small gap between the stirring blades of the lower rotating mechanism and the outer shell of the powder processing barrel, and the upper rotating mechanism comprises two or more shaping blades, and a central rotating shaft is connected to a driving motor outside the powder processing barrel, and can rotate at a high speed driven by the driving motor, and the driving motor of the upper rotating mechanism can realize forward and reverse switching, that is, the rotation directions of the upper rotating mechanism and the lower rotating mechanism can be the same or opposite, and there is a small gap between the shaping blades of the upper rotating mechanism and the outer shell of the powder processing barrel, and there is a certain distance between the upper rotating mechanism and the lower rotating mechanism. The powder processing tube is in an inverted cone shape and may be provided with an air inlet and an air outlet at the top, so as to achieve the purpose of vacuuming or replacing the atmosphere in the powder processing tube.

[0006] Preferably, the stirring blades of the lower rotating mechanism form a certain angle (obtuse angle) with the rotation direction, so as to better scoop up and lift the powder during the rotation process.

[0007] Preferably, the shaping blade of the upper rotating mechanism includes two positive and negative inclined surfaces. When the upper rotating mechanism rotates, the two inclined surfaces form different angles with the rotation direction, one of which is an acute angle and the other is an obtuse angle. The purpose of such design is: when the upper rotating mechanism and the lower rotating mechanism rotate in opposite directions, the angle between the inclined surface of the shaping blade facing the rotation direction of the upper rotating mechanism and the movement direction of the powder lifted by the lower rotating mechanism is close to vertical, so as to achieve a powder processing effect mainly based on impact crushing; and when the upper rotating mechanism and the lower rotating mechanism rotate in the same direction, the inclined surface of the shaping blade facing the rotation direction of the upper rotating mechanism is close to the movement direction of the powder lifted by the lower rotating mechanism, so as to achieve a powder processing effect mainly based on friction.

[0008] Preferably, the upper rotating mechanism may be composed of a plurality of groups of identical upper rotating mechanisms, which are evenly arranged on the upper part of the powder processing cylinder.

[0009] Preferably, the surface shape of the shaping blades of the upper rotating mechanism may be flat, wavy, porous honeycomb, etc.

[0010] Preferably, the driving motor is a variable frequency motor with adjustable speed, and the limiting speed of the upper rotating mechanism is greater than the limiting speed of the lower rotating mechanism.

[0011] The present invention also provides a powder processing method for improving the sphericity and surface smoothness of the powder, comprising the following steps: Step 1: Put the powder to be processed into the powder processing cylinder from the feeding inlet. The lower limit of the height of the powder should exceed half of the stirring blade of the lower rotating structure, and the upper limit should not exceed the bottom of the shaping blade of the upper rotating mechanism. Close the feeding inlet valve. Step 2: Evacuate the powder processing cylinder or replace the internal air with inert gas. Step 3: Turn on the drive motor of the lower rotating mechanism to make it rotate forward, and set the speed of the lower rotating mechanism to 500~1500r / min, then immediately turn on the drive motor of the upper rotating mechanism to make it rotate reversely, and set the speed of the upper rotating mechanism to 1000~4000r / min, maintain this rotation state for 10~60 minutes, and turn off the upper rotating mechanism motor after the time is up, and the lower rotating mechanism motor keeps rotating. Step 4: Change the rotation direction of the upper rotating mechanism to forward rotation, set the speed to 1000~3000r / min, turn on the drive motor of the upper rotating mechanism again, maintain the rotation state for 10~60 minutes, and then turn off all drive motors. The processed powder is discharged from the discharge port at the bottom of the powder processing cylinder to obtain powder with high powder sphericity and surface finish.

[0012] Compared with the prior art, the present invention has the following beneficial effects: In the powder processing process of the present invention, the stirring blades of the lower rotating mechanism can lift the powder upward and make the powder have a higher initial velocity. The movement direction of the lifted powder is similar to the rotation direction of the lower rotating mechanism. When the upper rotating mechanism and the lower rotating mechanism rotate in opposite directions, the angle between the inclined surface of the shaping blade facing the rotation direction of the upper rotating mechanism and the movement direction of the powder lifted by the lower rotating mechanism is close to vertical, and the shaping blade and the lifted powder move in opposite directions, and the relative speeds are superimposed. Therefore, the impact energy is greatly improved, and a significant powder processing effect mainly based on impact crushing can be achieved. At this time, the agglomerated powder and satellite powder can be efficiently crushed; when the upper rotating mechanism and the lower rotating mechanism rotate in the same direction, the inclined surface of the shaping blade facing the rotation direction of the upper rotating mechanism is similar to the movement direction of the powder lifted by the lower rotating mechanism, achieving a powder processing effect mainly based on friction, and the relative speed between the shaping blade and the lifted powder is low, which reduces the collision energy, thereby removing the edges and corners of the powder surface and improving the surface smoothness of the powder. At the same time, during the entire processing process, the stirring blades of the lower rotating mechanism quickly stir the powder in the powder processing cylinder, which can cause friction between the powder particles and significantly improve the surface finish of the powder. Therefore, the present invention uses one device to load powder at one time, and efficiently optimizes and improves the sphericity and surface finish of the powder at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The present invention is a schematic structural diagram of a powder processing device for improving the sphericity and surface smoothness of powder.

[0014] Figure 2 The present invention is a schematic diagram of the powder processing principle when the upper rotating mechanism and the lower rotating mechanism rotate in opposite directions during use of the powder processing device for improving the sphericity and surface finish of the powder.

[0015] Figure 3 The present invention is a schematic diagram of the powder processing principle when the upper rotating mechanism and the lower rotating mechanism rotate in the same direction during use of the powder processing device for improving the sphericity and surface smoothness of the powder.

[0016] Figure 4 This is a schematic structural diagram of a powder processing device for improving the sphericity and surface smoothness of powder proposed in Example 2 of the present invention.

[0017] Figure 5 This is a schematic diagram of the shape of the blades of the selection mechanism of a powder processing device for improving the sphericity and surface smoothness of powders proposed in Example 2 of the present invention. In the figure: 1. Upper rotating mechanism and shaping blades; 2. Lower rotating mechanism and stirring blades; 3. Powder processing cylinder; 4. Driving motor of upper rotating mechanism (can rotate forward and reverse); 5. Driving motor of lower rotating mechanism (forward); 6. Upper shaping blades; 7. Lower stirring blades. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the implementation regulations described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1 Reference Figure 1 , Figure 2 , Figure 3As shown, a powder processing device for improving the sphericity and surface finish of powder comprises a powder processing barrel 3 and a plurality of rotating mechanisms installed inside. The top of the powder processing barrel 3 is provided with a feeding port and a valve, and the bottom is provided with a feeding port and a valve. The rotating mechanism can be divided into an upper rotating mechanism 1 and a lower rotating mechanism 2. The lower rotating mechanism 2 comprises upper and lower groups of stirring blades 7. Each group of stirring blades 7 comprises four stirring blades 7. The central rotating shaft is connected to the driving motor 4 outside the powder processing barrel 3 and can rotate at a high speed under the drive of the driving motor 4. The rotation direction is defined as forward rotation. The stirring blades 7 of the lower rotating mechanism 2 are connected to the outer shell of the powder processing barrel 3. There is a 5mm gap between them. The upper rotating mechanism 1 has two sets of identical rotating mechanisms, which are symmetrically distributed on the top of the powder processing tube 3. Each upper rotating mechanism 1 includes four shaping blades 6, and the central rotating shaft is connected to the driving motor 5 outside the powder processing tube 3. It can rotate at high speed driven by the driving motor 5. The driving motor 5 of the upper rotating mechanism 1 can realize forward and reverse switching, that is, the rotation direction of the upper rotating mechanism 1 and the lower rotating mechanism 2 can be the same or opposite. There is a 5mm gap between the shaping blades 6 of the upper rotating mechanism 1 and the outer shell of the powder processing tube, and the distance between the upper rotating mechanism 1 and the lower rotating mechanism 2 is 20mm. The powder processing barrel 3 is an inverted cone, and the stirring blade 7 of the lower rotating mechanism 1 forms a certain angle (135°) with the rotation direction. The shaping blade 6 of the upper rotating mechanism 1 includes two positive and negative inclined surfaces. When the upper rotating mechanism 1 rotates, the two inclined surfaces form different angles with the rotation direction, one of which is an acute angle (45°) and the other is an obtuse angle (135°). The surface shape of the shaping blade 6 of the upper rotating mechanism 1 is a flat plate. The driving motors of the upper rotating mechanism 1 and the lower rotating mechanism 2 are variable frequency motors with adjustable speed. The speed adjustment range of the upper rotating mechanism 1 is 0-4000r / min, and the speed adjustment range of the lower rotating mechanism 2 is 0-1500r / min. The device of this embodiment is used to post-process the powder, and the preparation process includes: Step 1: Put the powder to be processed into the powder processing cylinder 3 from the feeding inlet, and the height of the powder put in is higher than the upper edge of the stirring blade of the lower rotating mechanism 2 and lower than the bottom edge of the shaping blade 6 of the upper rotating mechanism 1; Step 2: nitrogen is introduced into the air inlet of the powder processing cylinder 3 to replace the air in the cylinder with nitrogen; Step 3: Turn on the drive motor 4 of the lower rotating mechanism 2 to make it rotate forward, and set the speed of the lower rotating mechanism 2 to 1000r / min, then immediately turn on the drive motor 5 of the upper rotating mechanism 1 to make it rotate reversely, and set the speed of the upper rotating mechanism to 3000r / min, and keep this rotation state for 20 minutes. After the time is up, turn off the drive motor 5 of the upper rotating mechanism 1, and the drive motor 4 of the lower rotating mechanism 2 keeps rotating; In this step, the stirring blade 7 of the lower rotating mechanism 2 can scoop up and lift the powder during the rotation process, and make the powder have a higher initial velocity. The movement direction of the lifted powder is close to the rotation direction of the lower rotating mechanism 2. Since the upper rotating mechanism 1 and the lower rotating mechanism 2 rotate in opposite directions, the angle between the inclined surface of the shaping blade 6 facing the rotation direction of the upper rotating mechanism 1 and the movement direction of the powder lifted by the lower rotating mechanism is close to vertical, and the shaping blade 6 moves in opposite directions to the lifted powder, and the relative speeds are superimposed, so the impact energy is greatly improved, and a significant powder processing effect mainly based on impact crushing can be achieved; Step 4: Change the rotation direction of the upper rotating mechanism 1 to forward rotation, set the speed to 1500r / min, turn on the drive motor 5 of the upper rotating mechanism 1 again, keep the rotation state for 40 minutes, and then turn off all drive motors. The processed powder is discharged from the discharge port at the bottom of the powder processing cylinder to obtain powder with high powder sphericity and surface finish. At this time, the agglomerated powder and satellite ball powder can be efficiently crushed; In this step, the upper rotating mechanism 1 and the lower rotating mechanism 2 have the same rotation direction, and the inclined surface of the shaping blade 6 facing the rotation direction of the upper rotating mechanism 1 is close to the movement direction of the powder lifted by the lower rotating mechanism 2, thereby achieving a powder processing effect mainly based on friction, and the relative speed between the shaping blade 6 and the lifted powder is low, which reduces the energy of the collision, thereby being able to remove the edges and corners of the powder surface and improve the surface smoothness of the powder. During the entire preparation process, the stirring blades 7 of the lower rotating mechanism 2 quickly stir the powder in the powder processing cylinder 3, which can cause friction between the powder particles and significantly improve the surface smoothness of the powder.

[0019] Example 2 Reference Figure 4 , Figure 5As shown, a powder processing device for improving the sphericity and surface finish of powders comprises a powder processing barrel 3 and a plurality of rotating mechanisms installed inside, the top of the powder processing barrel 3 is provided with a feeding port and a valve, the bottom is provided with a feeding port and a valve, the rotating mechanism can be divided into an upper rotating mechanism 1 and a lower rotating mechanism 2, the lower rotating mechanism 2 comprises an upper and lower group of stirring blades 7, each group of stirring blades 7 comprises two stirring blades 7, and the central rotating shaft is connected to the driving motor 4 outside the powder processing barrel 3, and can be driven by the driving motor 4 to rotate at a high speed, and its rotation direction is defined as forward rotation, and the lower rotating mechanism There is a 10mm gap between the stirring blade 7 of 2 and the outer shell of the powder processing tube 3. The upper rotating mechanism 1 includes two shaping blades 6, and the central rotating shaft is connected to the driving motor 5 outside the powder processing tube 3, and can rotate at high speed driven by the driving motor 5. The driving motor 5 of the upper rotating mechanism 1 can realize forward and reverse switching, that is, the rotation direction of the upper rotating mechanism 1 and the lower rotating mechanism 2 can be the same or opposite. There is a 10mm gap between the shaping blade 6 of the upper rotating mechanism 1 and the outer shell of the powder processing tube, and the distance between the upper rotating mechanism 1 and the lower rotating mechanism 2 is 30mm. The powder processing barrel 3 is an inverted cone, and the stirring blade 7 of the lower rotating mechanism 1 forms a certain angle (135°) with the rotation direction. The shaping blade 6 of the upper rotating mechanism 1 includes two inclined surfaces on the front and back, one of which is flat and the other is wavy. When the upper rotating mechanism 1 rotates, the two inclined surfaces form different angles with the rotation direction, one of which is an acute angle (60°) and the other is an obtuse angle (120°). The driving motors of the upper rotating mechanism 1 and the lower rotating mechanism 2 are variable frequency motors with adjustable speed. The speed adjustment range of the upper rotating mechanism 1 is 0-4000r / min, and the speed adjustment range of the lower rotating mechanism 2 is 0-2000r / min. The device of this embodiment is used to post-process the powder, and the preparation process includes: Step 1: Put the powder to be processed into the powder processing cylinder 3 from the feeding inlet, and the height of the powder put in is higher than the upper edge of the stirring blade of the lower rotating mechanism 2 and lower than the bottom edge of the shaping blade 6 of the upper rotating mechanism 1; Step 2: Connect a vacuum pump to the exhaust port of the powder processing cylinder 3, close the air inlet, and evacuate to below 1000Pa; Step 3: Turn on the drive motor 4 of the lower rotating mechanism 2 to make it rotate forward, and set the speed of the lower rotating mechanism 2 to 1500r / min, then immediately turn on the drive motor 5 of the upper rotating mechanism 1 to make it rotate reversely, and set the speed of the upper rotating mechanism to 3500r / min, and keep this rotation state for 10 minutes. After the time is up, turn off the drive motor 5 of the upper rotating mechanism 1, and the drive motor 4 of the lower rotating mechanism 2 keeps rotating; In this step, the stirring blade 7 of the lower rotating mechanism 2 can scoop up and lift the powder during the rotation process, and make the powder have a higher initial velocity. The movement direction of the lifted powder is similar to the rotation direction of the lower rotating mechanism 2. Since the upper rotating mechanism 1 and the lower rotating mechanism 2 rotate in opposite directions, the angle between the inclined surface of the shaping blade 6 facing the rotation direction of the upper rotating mechanism 1 and the movement direction of the powder lifted by the lower rotating mechanism is close to vertical, and the shaping blade 6 is opposite to the movement direction of the lifted powder, and the relative speed is superimposed, so the impact energy is greatly improved, and a significant powder processing effect mainly based on impact crushing can be achieved; at the same time, in this example, the side of the shaping blade facing the rotation direction is a wavy surface, and the powder flying toward the surface at high speed can bounce on the pit surface many times, further improving the crushing processing efficiency. Step 4: Change the rotation direction of the upper rotating mechanism 1 to forward rotation, set the speed to 1500r / min, turn on the drive motor 5 of the upper rotating mechanism 1 again, keep the rotation state for 30 minutes, and then turn off all drive motors. The processed powder is discharged from the discharge port at the bottom of the powder processing cylinder to obtain powder with high powder sphericity and surface finish. At this time, the agglomerated powder and satellite ball powder can be efficiently crushed; In this step, the upper rotating mechanism 1 and the lower rotating mechanism 2 have the same rotation direction, and the inclined surface of the shaping blade 6 facing the rotation direction of the upper rotating mechanism 1 is close to the movement direction of the powder lifted by the lower rotating mechanism 2, thereby achieving a powder processing effect mainly based on friction, and the relative speed between the shaping blade 6 and the lifted powder is low, which reduces the energy of the collision, thereby being able to remove the edges and corners of the powder surface and improve the surface smoothness of the powder. During the entire preparation process, the stirring blades 7 of the lower rotating mechanism 2 quickly stir the powder in the powder processing cylinder 3, which can cause friction between the powder particles and significantly improve the surface smoothness of the powder. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A powder processing device for improving the sphericity and surface smoothness of powder, comprising a powder processing barrel and a plurality of rotating mechanisms installed inside, wherein a loading port and a valve are provided on the top of the powder processing barrel, and a unloading port and a valve are provided on the bottom, and the rotating stirring mechanism is divided into an upper rotating mechanism and a lower rotating mechanism, the upper rotating mechanism comprises two or more shaping blades, and the central rotating shaft is connected to the driving motor outside the powder processing barrel, and can rotate at a high speed under the drive of the driving motor, the driving motor of the upper rotating mechanism can realize forward and reverse switching, the lower rotating mechanism comprises two or more stirring blades, and the central rotating shaft is connected to the driving motor outside the powder processing barrel, and can rotate at a high speed under the drive of the driving motor, and there is a spacing of 1 to 5 cm between the upper rotating mechanism and the lower rotating mechanism.

2. A powder processing device for improving the sphericity and surface smoothness of powder according to claim 1, characterized in that: The stirring blade of the lower rotating mechanism forms a certain angle with the rotation direction, and the angle is an obtuse angle.

3. A powder processing device for improving the sphericity and surface smoothness of powder according to claim 1, characterized in that: The shaping blade of the upper rotating mechanism comprises two positive and negative inclined surfaces. When the upper rotating mechanism rotates, the two inclined surfaces form different angles with the rotating direction, one of which is an acute angle and the other is an obtuse angle.

4. A powder processing device for improving the sphericity and surface smoothness of powder according to claim 1, characterized in that: The upper rotating mechanism may be composed of one or more identical upper rotating mechanisms, which are evenly arranged on the upper part of the powder processing cylinder.

5. A powder processing device for improving the sphericity and surface smoothness of powder according to claim 1, characterized in that: The surface shape of the shaping blades of the upper rotating mechanism may be flat, wavy, porous honeycomb, etc.

6. A powder processing device for improving the sphericity and surface smoothness of powder according to claim 1, characterized in that: The driving motor is a variable frequency motor with adjustable speed, and the limit speed of the upper rotating mechanism is greater than or equal to the limit speed of the lower rotating mechanism.

7. A powder processing method for improving the sphericity and surface smoothness of powder, characterized in that: A powder processing device for improving the sphericity and surface smoothness of powders as described in the above claims is used, comprising the following steps: S1. Put the powder to be processed into the powder processing cylinder. The lower limit of the height of the powder should exceed half of the stirring blade of the lower rotating structure, and the upper limit should not exceed the bottom of the shaping blade of the upper rotating mechanism. S2. Evacuate the powder processing cylinder or replace the air inside with inert gas. S3. Turn on the drive motor of the lower rotating mechanism, define its rotation direction as forward, and set the speed of the lower rotating mechanism to 500~1500r / min, then immediately turn on the drive motor of the upper rotating mechanism to reverse it, and set the speed of the upper rotating mechanism to 1000~4000r / min, maintain this rotation state for 10~60 minutes, and turn off the drive motor of the upper rotating mechanism after the time is up, while the drive motor of the lower rotating mechanism keeps rotating. S4. Change the rotation direction of the upper rotating mechanism to forward rotation, set the speed to 0~3000r / min, turn on the drive motor of the upper rotating mechanism again, maintain the rotation state for 10~60 minutes, then turn off all the drive motors of the device, and discharge the material to obtain the powder with high sphericity and high surface finish.

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