Device for reducing satellite balls in gas atomization powder preparation process

Abstract

The utility model discloses a device for reducing satellite balls in the gas atomization pulverization process, which comprises an atomizing nozzle, an atomizing bin and an electromagnet device, the atomizing nozzle is arranged at the upper end of the atomizing bin, the lower end of the atomizing bin is provided with a first end part with a larger size and a second end part with a smaller size, and the electromagnet device is arranged at the lower end of the atomizing bin. The first end part is arranged between the atomizing nozzle and the second end part, and the second end part is connected with an external cyclone grading device; and the electromagnet device is arranged between the first end part and the second end part. The electromagnet device is arranged on the second end portion of the lower end of the atomization bin to adsorb cooled metal powder, and the situation that the metal powder collides with coarse powder which is not completely condensed to form satellite balls is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of aerosol powder making, in particular to a device for reducing satellite balls in the aerosol powder making process. Background Art

[0002] Vacuum gas atomization powder making is one of the important methods for producing high-quality powder for 3D printing. Vacuum gas atomization powder making is to melt molten steel under vacuum or inert gas protection conditions, then pour the molten steel into the tundish to form fine liquid columns that flow into the atomization chamber through the atomization nozzle. The molten steel is broken by the inert high-pressure gas and then cooled into metal powder.

[0003] The current problem is that the metal powder that has been condensed during the cooling process will move irregularly in the atomization chamber. When the condensed metal powder encounters the coarse powder that has not been completely cooled during the movement, it will stick to it and form a satellite ball.

[0004] The fluidity of metal powder is an important evaluation index of powder quality, and the satellite balls adhered to the surface of powder particles are an important factor affecting the fluidity of powder.

[0005] At present, the method to reduce satellite balls is to apply a protective air curtain around the area where the molten steel is broken to prevent the swirling airflow carrying the cooled metal powder from colliding with the incompletely condensed coarse powder to form satellite balls.

[0006] In the prior art, in order to prevent the alloy liquid from being oxidized, a high-purity gas is required to form a protective gas curtain, which has the problems of increased gas consumption, increased cost, and higher requirements for the exhaust volume per unit time of the exhaust system, which may further deteriorate the powder morphology. Utility Model Content

[0007] In view of this, the purpose of the utility model is to provide a device for reducing satellite balls in the aerosol powder making process.

[0008] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0009] A device for reducing satellite balls in a gas atomization powder making process, comprising:

[0010] Atomizing nozzle, atomizing chamber and electromagnet device;

[0011] An atomizing bin, wherein the atomizing nozzle is arranged at the upper end of the atomizing bin, and the atomizing bin is used to prevent the incompletely cooled powder from contacting with the air to prevent the powder from being oxidized; the lower end of the atomizing bin has a first end with a larger size and a second end with a smaller size, the first end is arranged between the atomizing nozzle and the second end, and the second end is connected to an external cyclone cyclone classifying device; the electromagnet device is arranged between the first end and the second end.

[0012] The above-mentioned device for reducing satellite balls during the aerosol powder making process, wherein the first end and the second end are both annular, and the lower end of the atomization bin also includes: a connecting part, the two ends of the connecting part are respectively connected to the first end and the second end, and the electromagnet device is installed on the connecting part.

[0013] The device for reducing satellite balls in the aerosol powder making process is as follows: the electromagnet device comprises a plurality of electromagnets, and the plurality of electromagnets are arranged in a Halbach array.

[0014] The device for reducing satellite balls in the aerosol powder making process is as follows: the electromagnet device has a first side with greater magnetism and a second side with less magnetism, and the first side of the electromagnet device with greater magnetism is arranged toward the interior of the atomization bin.

[0015] In the above-mentioned device for reducing satellite balls during the aerosol powder making process, a plurality of the electromagnets are arranged along the connecting portion to form a ring.

[0016] In the above-mentioned device for reducing satellite balls in the aerosol powder making process, the number of the electromagnets is 4*N, wherein N is an integer between 4 and 9.

[0017] The device for reducing satellite balls in the aerosol powder making process mentioned above, wherein the number of the electromagnets is 24.

[0018] The above-mentioned device for reducing satellite balls in the aerosol powder making process, wherein the length of each of the electromagnets is 15 cm, the width of each of the electromagnets is 15 cm, and the thickness of each of the electromagnets is 10 cm.

[0019] The above-mentioned device for reducing satellite balls in the aerosol powder making process, wherein the number of the cyclone cyclone classifying devices is several, and the several cyclone cyclone classifying devices are connected in sequence and then connected to the second end.

[0020] The above-mentioned device for reducing satellite balls in the aerosol powder making process, wherein several of the cyclone classifying devices achieve different classification levels.

[0021] The above-mentioned device for reducing satellite balls during the aerosol powder making process, wherein the upper end of the atomization bin has a third end with a smaller size and a fourth end with a larger size, the fourth end is located between the third end and the electromagnet device, and the atomization nozzle is installed on the third end.

[0022] Due to the adoption of the above technology, the utility model has the following positive effects compared with the prior art:

[0023] (1) The utility model provides an electromagnet device at the second end of the lower end of the atomization bin to adsorb the metal powder that has been cooled, so as to prevent the metal powder from colliding with the coarse powder that has not been cooled and not completely condensed to form a satellite ball. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a device for reducing satellite balls in the aerosol powder making process of the utility model.

[0025] Figure 2 It is a schematic diagram of an electromagnet device of a device for reducing satellite balls in the aerosol powder making process of the utility model.

[0026] In the accompanying drawings: 1, atomizing nozzle; 2, atomizing chamber; 3, cyclone cyclone classifying device; 21, second end; 22, first end; 23, third end; 24, fourth end; 25, electromagnet device; 251, electromagnet; 252, first side; 253, second side. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention. Figure 1 It is a schematic diagram of a device for reducing satellite balls in the aerosol powder making process of the utility model; Figure 2 This is a schematic diagram of the electromagnet device of the device for reducing satellite balls in the aerosol powder making process of the utility model, see Figure 1 to Figure 2 As shown, a device for reducing satellite balls in the process of aerosol powder making according to a preferred embodiment is shown, comprising: an atomizing nozzle 1, an atomizing bin 2 and an electromagnet device 25, wherein the atomizing nozzle 1 is arranged at the upper end of the atomizing bin 2, and the atomizing bin 2 is used to prevent the incompletely cooled powder from contacting with the air to prevent the powder from being oxidized; the lower end of the atomizing bin 2 has a first end 22 with a larger size and a second end 21 with a smaller size, the first end 22 is arranged between the atomizing nozzle 1 and the second end 21, and the second end 21 is connected to an external cyclone cyclone classifying device 3; the electromagnet device 25 is arranged between the first end 22 and the second end 21.

[0028] In a preferred embodiment, the first end 22 and the second end 21 are both annular, and the lower end of the atomization chamber 2 also includes: a connecting portion, the two ends of the connecting portion are respectively connected to the first end 22 and the second end 21, and the electromagnet device 25 is installed on the connecting portion.

[0029] In a preferred embodiment, the electromagnet device 25 includes a plurality of electromagnets 251, and the plurality of electromagnets 251 are arranged in a Halbach array.

[0030] In a preferred embodiment, the electromagnet device 25 has a first side 252 with greater magnetism and a second side 253 with less magnetism, and the first side 252 of the electromagnet device 25 with greater magnetism is arranged toward the interior of the atomization chamber 2 .

[0031] The above are only preferred embodiments of the present invention, and are not intended to limit the implementation methods and protection scope of the present invention.

[0032] The utility model also has the following implementation methods based on the above:

[0033] In a further embodiment of the present invention, a plurality of electromagnets 251 are arranged along the connecting portion to form a ring.

[0034] In a further embodiment of the present invention, the number of the electromagnets 251 is 4*N, wherein N is an integer between 4 and 9.

[0035] Preferably, the number of the electromagnets 251 is 24.

[0036] In a further embodiment of the present invention, the length of each electromagnet 251 is 15 cm, the width of each electromagnet 251 is 15 cm, and the thickness of each electromagnet 251 is 10 cm.

[0037] In a further embodiment of the present invention, there are a plurality of cyclone classifying devices 3 , and the plurality of cyclone classifying devices 3 are connected in sequence and then connected to the second end portion 21 .

[0038] In a further embodiment of the present invention, a plurality of cyclone classifying devices 3 achieve different classification levels.

[0039] In a preferred embodiment, the cyclone cyclone classifying device 3 in the present device can select the cyclone classifying device in the Chinese utility model patent, publication number: CN 202962698 U, and the cyclone classifying device; in another preferred embodiment, the cyclone cyclone classifying device 3 in the present device can select the cyclone classifying structure in the Chinese utility model patent, a particle size classification device for 3D metal powder production, publication number: CN 203343085U.

[0040] In a further embodiment of the utility model, the upper end of the atomizing bin 2 has a third end 23 of smaller size and a fourth end 24 of larger size, the fourth end 24 is located between the third end 23 and the electromagnet device 25, and the atomizing nozzle 1 is installed on the third end 23.

[0041] In a preferred embodiment, the molten steel is crushed by the atomizing nozzle 1 and the metal powder is formed and then enters the atomizing chamber 2 .

[0042] In a preferred embodiment, the connecting portion is in a truncated cone shape.

[0043] In a preferred embodiment, the Halbach array is Figure 2 As shown, the magnetic field on the first side 252 can be enhanced while the magnetic field on the second side 253 can be weakened, and the strength of the magnetic field can be adjusted by adjusting the current in the electromagnet 251; further, the first side 252 has suction on the metal powder, and the electromagnet device 25 is arranged at the lower end of the atomization bin 2. After the metal powder moves to the electromagnet device 25, it passes through the space in the atomization bin 2 surrounded by inert gas, thereby achieving cooling; the cooled metal powder is adsorbed to the connecting part by the magnetism generated by the electromagnet device 25, thereby preventing the cooled metal powder from moving in the atomization bin 2 and sticking to the coarse powder that has not been completely cooled, thereby forming a satellite ball.

[0044] It is worth noting that in the prior art, the metal is heated and melted into molten steel in the smelting chamber, and the molten steel flows down from the middle of the atomizing nozzle 1, and is broken and cooled into metal powder by the high-speed gas ejected from the atomizing nozzle 1. The high-speed airflow carries the metal powder to the bottom of the atomizing bin 2, and the airflow is intercepted by the bottom of the atomizing bin 2 and slowed down. At the same time, because the air pressure in the area where the top of the atomizing bin 2 is not on the path of the high-speed airflow is relatively low, the gas that slows down at the bottom swirls back to the top of the atomizing bin 2 along the wall of the atomizing bin 2. In this process, since the weight of the cooled metal powder is very light and the gravity and inertia it is subjected to are small, the condensed cooled metal powder will return to the top of the atomizing bin 2 with the airflow; and the present device is provided with an electromagnet device 25 at the bottom of the atomizing bin 2, and the cooled metal powder no longer swirls back to the top of the atomizing bin 2, which fundamentally reduces the probability of the formation of satellite balls.

[0045] In a preferred embodiment, the atomizing bin 2 in the device maintains the original structure, ensuring that the atomizing capability of the atomizing nozzle 1 is not changed, thereby reducing the number of satellite balls and not increasing the cost too much.

[0046] In a preferred embodiment, the bottom of the atomization bin 2 is a circle with a diameter of 130 cm, and 24 electromagnets 251 are used according to Figure 2 The magnetic field is arranged in a circular manner at the bottom of the atomization bin 2, and the position of the electromagnet 251 is fixed using glue with strong viscosity, and then the power supply of the electromagnet 251 is turned on to complete the production of the device.

[0047] In a preferred embodiment, when in use, the entire atomization chamber 2 is evacuated to a vacuum degree of less than 10 Pa, and then filled with high-purity argon gas to standard atmospheric pressure; 24 electromagnets 251 are prepared according to Figure 2 The array is arranged in an array and placed at the bottom of the atomization bin 2.

[0048] Further, when in use, the stainless steel is melted at a power of 150kw to 180kw; the power switch of the electromagnet device 25 is turned on, the current is adjusted to 0.7A, the high-pressure gas switch connected to the atomization bin 2 is turned on, and the air pressure is adjusted to 4MPa; the molten steel is poured to start atomization, and the ultrafine metal powder carried by the swirling airflow is adsorbed on the wall of the atomization bin 2 by the magnetic field, and cannot contact the metal droplets that have not been completely cooled, reducing the satellite ball; after the atomization is completed, the switch of the electromagnet device 25 is turned off, and the high-pressure air pressure is reduced to 2MPa and continues to purge for 1 minute. After the metal powder is cooled for 40 minutes, the obtained metal powder is collected.

[0049] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for reducing satellite balls in the process of aerosol powder making, characterized in that: include: Atomizing nozzle, atomizing chamber and electromagnet device; The atomizing nozzle is arranged at the upper end of the atomizing bin, and the atomizing bin is used to prevent the incompletely cooled powder from contacting with the air to prevent the powder from being oxidized; the lower end of the atomizing bin has a first end with a larger size and a second end with a smaller size, the first end is arranged between the atomizing nozzle and the second end, and the second end is connected to an external cyclone cyclone classifying device; the electromagnet device is arranged between the first end and the second end.

2. The device for reducing satellite balls in the aerosol powder making process according to claim 1, characterized in that: The first end and the second end are both annular, and the lower end of the atomization bin further includes: a connecting portion, two ends of the connecting portion are respectively connected to the first end and the second end, and the electromagnet device is installed on the connecting portion.

3. The device for reducing satellite balls in the aerosol powder making process according to claim 2, characterized in that: The electromagnet device includes a plurality of electromagnets, and the plurality of electromagnets are arranged in a Halbach array.

4. The device for reducing satellite balls in the aerosol powder making process according to claim 3, characterized in that: The electromagnet device has a first side with greater magnetism and a second side with less magnetism, and the first side of the electromagnet device with greater magnetism is arranged toward the interior of the atomization bin.

5. The device for reducing satellite balls in the aerosol powder making process according to claim 3, characterized in that: A plurality of the electromagnets are arranged along the connecting portion to form a ring.

6. The device for reducing satellite balls in the aerosol powder making process according to claim 5, characterized in that: The number of the electromagnets is 4*N, wherein N is an integer between 4 and 9.

7. The device for reducing satellite balls in the aerosol powder making process according to claim 5, characterized in that: The length of each electromagnet is 15 cm, the width of each electromagnet is 15 cm, and the thickness of each electromagnet is 10 cm.

8. The device for reducing satellite balls in the aerosol powder making process according to claim 1, characterized in that: The number of the cyclone cyclone classifying devices is multiple, and the multiple cyclone cyclone classifying devices are connected in sequence and then connected to the second end.

9. The device for reducing satellite balls in the aerosol powder making process according to claim 7, characterized in that: The cyclone classifying devices described above achieve different levels of classification.

10. The device for reducing satellite balls in the aerosol powder making process according to claim 1, characterized in that: The upper end of the atomizing bin has a third end with a smaller size and a fourth end with a larger size. The fourth end is located between the third end and the electromagnet device. The atomizing nozzle is installed on the third end.

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