Centrifugal crucible with composite structure for secondary atomization of metal powder

Abstract

The utility model relates to a centrifugal crucible with a composite structure for secondary atomization of metal powder, which belongs to the technical field of metal powder, overcomes the problems of weaker crushing effect on metal liquid drops and low atomization efficiency in the prior art, and is characterized in that a centrifugal crucible folding edge is arranged on the upper edge of the centrifugal crucible, a centrifugal crucible heat insulation body is correspondingly arranged below a crucible groove, and the centrifugal crucible heat insulation body is arranged below the crucible groove. An air knife shell with a flange at the bottom end is arranged outside the centrifugal crucible protective cover, an air knife shell folded edge is arranged on the upper portion of the air knife shell, and an air knife opening with an air knife function is formed by an annular narrow slit formed by the centrifugal crucible folded edge and the air knife shell folded edge. An annular air knife is formed by an air channel formed by a gap between the outer wall of the centrifugal crucible protection cover and the inner wall of the air knife shell and the air knife edge, and the air knife has the beneficial effects that the atomization efficiency is improved, the secondary crushing and atomization effect on metal liquid drops is increased, the atomization effect of the metal liquid drops is improved, and the service life of the metal liquid drops is prolonged. And meanwhile, a certain protection effect on the main shaft system and the centrifugal crucible is achieved, and smooth proceeding of the centrifugal powder making process is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the technical field of metal powder making equipment, and particularly relates to a centrifugal crucible with a composite structure used for secondary atomization metal powder making. Background Art

[0002] The centrifugal crucible is a key component of centrifugal powder making. There are many types of crucibles in the prior art, but there is no centrifugal crucible for centrifugal powder making that has the function of secondary atomization of metal droplets and has a composite structure.

[0003] The invention with application number CN201910161526.0 discloses "a device for preparing metal alloy powder". The device described in the invention includes an air suction smelting chamber, a powder making chamber, a powder temporary storage chamber and a secondary crushing spheroidization chamber arranged from top to bottom. The device described in the invention adopts a high-pressure active atmosphere environment to melt high-temperature metal alloys to reduce its melting point and interfacial tension, and improve the fluidity of the metal alloy melt. The high-pressure jet is triggered by the high-pressure active atmosphere, and the metal alloy powder is prepared by centrifugal atomization. A water-cooled copper crucible is arranged in the air suction smelting chamber of the invention, and a main heating induction coil is arranged on the periphery of the water-cooled copper crucible, but the water-cooled copper crucible described in the invention is fixed and suitable for melting high-temperature metal alloys in a high-pressure active atmosphere environment, but not suitable for the high-speed rotating centrifugal crucible required for the metal centrifugal powder making device.

[0004] The utility model with application number CN201320286944.0 discloses "a centrifugal powder making device for hydrogen storage alloy". The utility model includes a vacuum system and a vacuum melting furnace. A reversible crucible and a heat preservation furnace are provided in the vacuum melting furnace. The lower end of the heat preservation furnace is connected to a flow control tube. A centrifugal atomizer is provided under the flow control tube. The motor drives the centrifugal atomizer to directly atomize the molten metal into metal powder. The centrifugal atomizer, the heating furnace and the motor are placed in a collector. A discharge valve is provided at the bottom of the vacuum melting furnace. The utility model adopts two types of centrifugal atomizers. The first type is a cylindrical centrifugal atomizer without holes. Under the action of centrifugal force, the molten liquid forms a thin film along the inner wall of the atomizer and rises. When the thin film reaches the edge, it becomes fine droplets and flies out from the edge to the surrounding areas. During the flight, the melt is transformed into spherical particles under the action of surface tension, and heat exchanges with argon gas, gradually cools down and becomes solid powder, and further cools down when it reaches the collector, and is discharged from the discharge valve; the second type is a cylindrical atomizer with a plurality of side holes at equal distances on the side wall. Under the action of centrifugal force, the molten liquid forms a thin film along the inner wall of the atomizer and rises. When it reaches the side holes on the side wall of the atomizer, it flies out from the side holes to the surrounding areas outside the atomizer. During the flight, the melt is transformed into spherical particles under the action of surface tension, and heat exchanges with argon gas, gradually cools down and becomes solid powder, and further cools down when it reaches the collector, and is discharged from the discharge valve. However, no matter it is a cylindrical centrifugal atomizer without holes or a cylindrical centrifugal atomizer with a plurality of side holes formed at equal distances on the side wall, the molten metal is directly atomized into metal powder, and the result of one-time atomization is achieved. The melt is transformed into spherical particles only by the action of surface tension during flight, and the atomization effect is weak and the atomization efficiency is low. Utility Model Content

[0005] The technical problem to be solved by the utility model is to overcome the shortcomings of the prior art and provide a composite crucible with a crucible and an air knife structure to realize the function of secondary atomization of metal droplets, and a heating and multi-level thermal insulation protection function, so as to reduce the huge damage caused by heat conduction of the crucible to the spindle system and realize secondary atomization powder making, thereby improving the atomization effect of metal droplets and the low atomization efficiency. A centrifugal crucible with a composite structure for secondary atomization metal powder making.

[0006] The technical scheme adopted by the utility model comprises a centrifugal crucible, a centrifugal crucible protective cover is installed on the outside of the centrifugal crucible, a centrifugal crucible heating body for heating the centrifugal crucible is installed between the centrifugal crucible protective cover and the centrifugal crucible, a centrifugal crucible folding edge is provided on the upper edge of the centrifugal crucible, a crucible groove is provided at the center of the crucible bottom of the centrifugal crucible, a centrifugal crucible heat insulator is correspondingly installed below the crucible groove of the centrifugal crucible, a wind knife shell with a flange at the bottom end is provided outside the centrifugal crucible protective cover, a wind knife shell folding edge is provided on the upper part of the wind knife shell, an annular narrow slit formed by the centrifugal crucible folding edge and the wind knife shell folding edge constitutes a wind knife mouth with a wind knife function, a gap between the outer wall of the centrifugal crucible protective cover and the inner wall of the wind knife shell forms a gas channel, and the gas channel and the wind knife mouth formed by the gap between the outer wall of the centrifugal crucible protective cover and the inner wall of the wind knife shell constitute an annular wind knife.

[0007] The annular narrow slit gap of the wind knife edge is 0.1-2 mm, and the gap of the gas channel is 5-10 mm.

[0008] A disc-shaped upper insulation pad is installed in the crucible groove between the centrifugal crucible and the centrifugal crucible insulator, an annular upper insulation pad is installed on the lower edge boss of the crucible groove of the centrifugal crucible, and a disc-shaped lower insulation pad is installed below the centrifugal crucible insulator.

[0009] The centrifugal crucible insulator is provided with a stepped screw hole, in which a centrifugal crucible fastening screw is used to connect the centrifugal crucible insulator and the centrifugal crucible as a whole, a line inlet hole for energizing the centrifugal crucible heating body and a protective cover bolt hole are provided at the bottom of the centrifugal crucible protective cover, and a connecting hole connected to the main shaft sleeve is provided on the flange of the air knife housing.

[0010] An annular cavity is formed between the inner wall of the centrifugal crucible protection cover and the outer wall of the centrifugal crucible and is filled with a heat conduction medium.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] (1) The utility model adopts a centrifugal crucible with a composite structure, that is, a protective cover is provided outside the centrifugal crucible, an electric heating element is arranged between the centrifugal crucible and the protective cover and filled with a heat conduction medium, a heat insulator and a multi-layer heat insulation pad are provided at the bottom of the centrifugal crucible to slow down the heat transfer of the high-temperature centrifugal crucible body downward, an annular wind knife shell is installed outside the centrifugal crucible protective cover, and the gas channel and wind knife mouth formed by the gap between the outer wall of the centrifugal crucible protective cover and the inner wall of the wind knife shell constitute an annular wind knife. The inert gas blown out by the annular wind knife performs secondary gas atomization on the fine droplets after centrifugal atomization to prepare ultra-fine metal powder, further improving the atomization effect of the metal droplets. At the same time, the inert gas cools the connection between the bottom of the centrifugal crucible and the main shaft and the protective cover shell, playing a certain protective role on the main shaft system and the centrifugal crucible.

[0013] (2) By using the utility model, the centrifugal crucible protective cover can be cooled by circulating inert cooling gas, ensuring that the centrifugal crucible heating body continues to heat the centrifugal crucible and the components connected thereto. At the same time, the hot gas formed by heat exchange is passed through the wind knife at the upper end of the gas channel to perform secondary atomization on the metal droplets thrown out of the centrifugal crucible, thereby improving the atomization efficiency, increasing the secondary crushing and atomization effect on the metal droplets, and further improving the atomization effect of the metal droplets. The metal droplets are cooled and condensed into finer metal powders under the inert gas atmosphere in the powder making furnace body. The heating device provided in the centrifugal crucible and the protective shell can ensure that the centrifugal crucible has a sufficiently high temperature to ensure that the metal liquid is at a suitable centrifugal temperature, thereby ensuring the smooth progress of the centrifugal powder making process. The inert gas used for secondary gas atomization is used to air-cool the centrifugal powder making main shaft system, the connection part with the centrifugal crucible and the crucible protective cover before entering the wind knife, thereby achieving the purpose of protecting the entire powder making main shaft and crucible system, and ensuring the smooth operation of key components in centrifugal powder making. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model.

[0015] Figure 2 yes Figure 1 A top view of

[0016] Figure 3 yes Figure 1 A partial enlarged view of point A.

[0017] In the figure:

[0018] 1. Centrifugal crucible heating element,

[0019] 2. Centrifugal crucible, 2-1. Folding the edge of the centrifugal crucible,

[0020] 3. Fasten the centrifugal crucible screws,

[0021] 4. Disc-shaped upper insulation pad,

[0022] 5. Wind Knife Edge,

[0023] 6. Annular heating chamber,

[0024] 7. Centrifugal crucible protection cover, 7-1. Power inlet hole, 7-2. Protection cover bolt hole,

[0025] 8. Gas channel,

[0026] 9. Wind knife shell, 9-1. Wind knife shell folding edge, 9-2. Connection hole,

[0027] 10. Ring-shaped upper insulation pad,

[0028] 11. Centrifugal crucible insulator, 11-1. Stepped screw hole

[0029] 12. Disc-shaped lower insulation pad,

[0030] 13. Heat transfer medium. DETAILED DESCRIPTION

[0031] like Figure 1 , Figure 2 and Figure 3As shown, the main structure of the utility model is a cylindrical structure. Specifically, the technical solution adopted by the utility model includes a centrifugal crucible 2, the upper edge of the side wall of the centrifugal crucible 2 is thin and the bottom end is thick, so that the inner wall of the centrifugal crucible 2 forms a cone with a large upper opening and a small lower part, a centrifugal crucible fold 2-1 is provided on the upper edge of the centrifugal crucible 2, a crucible groove is provided at the center of the crucible bottom of the centrifugal crucible 2, a centrifugal crucible insulator 11 is correspondingly installed below the crucible groove of the centrifugal crucible 2, a disc-shaped upper insulation pad 4 and a ring-shaped upper insulation pad 10 are installed between the centrifugal crucible 2 and the centrifugal crucible insulator 11, and below the centrifugal crucible insulator 11 A disc-shaped lower insulation pad 12 is installed. Furthermore, a disc-shaped upper insulation pad 4 is installed in the crucible groove of the centrifugal crucible 2, and an annular upper insulation pad 10 is installed on the boss at the lower edge of the crucible groove of the centrifugal crucible 2. The crucible groove of the centrifugal crucible 2 and the boss of the centrifugal crucible insulation body 11 can cooperate with the centrifugal crucible 2 to center the centrifugal crucible 2 and ensure the stability of the high-speed rotation of the centrifugal crucible 2; a centrifugal crucible protection cover 7 is installed on the outside of the centrifugal crucible 2, and a centrifugal crucible heating body 1 for heating the centrifugal crucible 2 is installed between the centrifugal crucible protection cover 7 and the centrifugal crucible 2, and a centrifugal crucible heating body 1 for heating the centrifugal crucible 2 is installed between the inner wall of the centrifugal crucible protection cover 7 and the outer wall of the centrifugal crucible 2. An annular heating cavity 6 is formed between the centrifugal crucible and filled with a heat conducting medium 13. The centrifugal crucible heater 1 is a heating resistance wire or a heating induction coil. A wind knife shell 9 with a flange at the bottom is provided outside the centrifugal crucible protection cover 7. A wind knife shell fold 9-1 is provided on the upper part of the wind knife shell 9. The centrifugal crucible fold 2-1 of the centrifugal crucible 2 and the wind knife shell fold 9-1 on the upper part of the wind knife shell 9 form an annular narrow gap to form a wind knife mouth 5 with a wind knife function. The annular narrow gap of the wind knife mouth 5 is 0.1-2mm. The gap between the outer wall of the centrifugal crucible protection cover 7 and the inner wall of the wind knife shell 9 forms a gas channel 8. The gap of the gas channel is 5 to 10 mm, and the gas channel 8 and the wind knife mouth 5 formed by the gap between the outer wall of the centrifugal crucible protective cover 7 and the inner wall of the wind knife shell 9 constitute an annular wind knife. The centrifugal crucible insulator 11 is provided with a stepped screw hole 11-1, and the centrifugal crucible fastening screw 3 is used in the stepped screw hole 11-1 to connect the centrifugal crucible insulator 11 and the centrifugal crucible 2 as a whole; at the bottom of the centrifugal crucible protective cover 7, there are provided a power inlet hole 7-1 for powering the centrifugal crucible heating body 1 and a protective cover bolt hole 7-2, and a connecting hole 9-2 connected to the main shaft sleeve is provided on the flange of the wind knife shell 9.

[0032] When in use, the air knife housing 9 is connected to the spindle sleeve through the air knife housing connection hole 9-2; the lower end of the gas channel 8 is connected to the spindle cooling air in the inner shell of the centrifugal spindle sleeve, and is connected with the spindle flange by aligning the protection cover bolt hole 7-2 on the centrifugal crucible protection cover 7 with the spindle flange, thereby connecting the centrifugal crucible protection cover 7 with the spindle as a whole, so that the centrifugal crucible protection cover 7, the centrifugal crucible 2, the centrifugal crucible insulation body 11, the disc-shaped upper insulation pad 4, the annular upper insulation pad 10, the centrifugal crucible heating body 1 and its heat conduction medium are connected to the centrifugal crucible protection cover 7. The disc-shaped lower thermal insulation pad 12 is fixedly connected to the same rotating body. The inert cooling gas circulated in cools the centrifugal crucible protection cover 7 on the one hand, ensuring that the heat transferred from the centrifugal crucible heating body 1 when continuously heating the centrifugal crucible 2 will not cause the centrifugal crucible protection cover 7 and the centrifugal main shaft connected thereto to overheat. At the same time, the hot gas formed by heat exchange passes through the wind knife mouth 5 of the annular wind knife to perform secondary atomization on the metal droplets after centrifugal atomization of the centrifugal crucible 2, thereby obtaining a metal powder with finer particle size.

Claims

1. A centrifugal crucible with a composite structure for secondary atomization of metal powder, comprising a centrifugal crucible (2), a centrifugal crucible protection cover (7) installed outside the centrifugal crucible (2), and a centrifugal crucible heating body (1) installed between the centrifugal crucible protection cover (7) and the centrifugal crucible (2) for heating the centrifugal crucible (2), characterized in that: A centrifugal crucible fold (2-1) is provided on the upper edge of the centrifugal crucible (2), a crucible groove is provided at the center of the crucible bottom of the centrifugal crucible (2), a centrifugal crucible heat insulator (11) is installed correspondingly below the crucible groove of the centrifugal crucible (2), a wind knife shell (9) with a flange at the bottom is provided outside the centrifugal crucible protection cover (7), a wind knife shell fold (9-1) is provided on the upper part of the wind knife shell (9), a wind knife opening (5) with a wind knife function is formed by an annular narrow gap formed by the centrifugal crucible fold (2-1) and the wind knife shell fold (9-1), a gas channel (8) is formed by the gap between the outer wall of the centrifugal crucible protection cover (7) and the inner wall of the wind knife shell (9), and the gas channel (8) and the wind knife opening (5) formed by the gap between the outer wall of the centrifugal crucible protection cover (7) and the inner wall of the wind knife shell (9) constitute an annular wind knife.

2. A centrifugal crucible with a composite structure for secondary atomization of metal powder according to claim 1, characterized in that: The annular narrow slit gap of the wind knife edge (5) is 0.1 to 2 mm, and the gap of the gas channel (8) is 5 to 10 mm.

3. A centrifugal crucible with a composite structure for secondary atomization of metal powder according to claim 1 or 2, characterized in that: A disc-shaped upper thermal insulation pad (4) is installed in the crucible groove between the centrifugal crucible (2) and the centrifugal crucible insulator (11), an annular upper thermal insulation pad (10) is installed on the boss at the lower edge of the crucible groove of the centrifugal crucible (2), and a disc-shaped lower thermal insulation pad (12) is installed below the centrifugal crucible insulator (11).

4. A centrifugal crucible with a composite structure for secondary atomization of metal powder according to claim 1 or 2, characterized in that: The centrifugal crucible heat insulator (11) is provided with a stepped screw hole (11-1), in which a centrifugal crucible fastening screw (3) is used to connect the centrifugal crucible heat insulator (11) and the centrifugal crucible (2) as a whole; a line inlet hole (7-1) for supplying electricity to the centrifugal crucible heating body (1) and a protective cover bolt hole (7-2) are provided at the bottom of the centrifugal crucible protective cover (7); and a connecting hole (9-2) connected to the main shaft sleeve is provided on the flange of the air knife housing (9).

5. A centrifugal crucible with a composite structure for secondary atomization of metal powder according to claim 1 or 2, characterized in that: An annular cavity (6) is formed between the inner wall of the centrifugal crucible protection cover (7) and the outer wall of the centrifugal crucible (2), and is filled with a heat conduction medium (13).

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