A metal liquid flow atomization nozzle

Abstract

The present invention provides a metal liquid flow atomization nozzle, which includes a housing. An annular high-pressure gas flow channel is provided inside the housing, and an annular slit is provided on the bottom wall of the high-pressure gas flow channel to form a high-pressure jet gas flow channel; one end of the inlet of the high-pressure jet gas flow channel is communicated with the high-pressure gas flow channel; the diameter of the outlet end of the high-pressure jet gas flow channel gradually decreases along the gas flow direction to form a tapered contraction port; a metal liquid flow channel is penetrated and provided on the housing on the inner ring side of the high-pressure gas flow channel; the extension lines of the tapered contraction port intersect, and the intersection point is located on the central axis of the metal liquid flow channel; the high-pressure jet gas flow channel is arranged to first contract and then expand from its inlet end to its outlet end; the cross-section of the high-pressure jet gas flow channel is an elliptical ring, and the eccentricity of the elliptical ring of the high-pressure jet gas flow channel is controlled between 0.24 and 0.45. The nozzle of the present invention can improve the problem that the liquid flow at the core of the nozzle is not completely broken, and improve the size stability of the powder after fragmentation.

Description

Technical Field

[0001] The present invention relates to the field of metal processing, and particularly to a metal liquid flow atomization nozzle. Background Art

[0002] The gas atomization method is widely used in the preparation of metal powders (including pure metal powders and alloy powders). Its principle is to use a high-speed moving gas flow to break up a metal liquid flow into a mist of powders, and after cooling and screening, metal and alloy powders are obtained. When the liquid metal is continuously broken into fine droplets, the kinetic energy of the high-speed gas flow is converted into the surface energy of the metal droplets to increase the total surface area. The atomizing gas flow generally uses a jet flow mode that forms an angle with the metal liquid flow to atomize the metal liquid flow.

[0003] Currently, the research on gas atomization preparation devices for metal powders mainly focuses on how to obtain finer metal powders (such as the patent with the application publication number CN 110508826A), and there is little research on how to improve the uniformity of metal powders.

[0004] Moreover, the patent with the application publication number CN 110508826A achieves the purpose of obtaining ultra-fine metal powders through two-stage atomization, doubling the gas consumption and resulting in a sharp increase in costs; and the metal liquid flow channel changes from a vertical channel to an annular channel. In the case of the same liquid flow rate, the width of the annular channel is narrower than that of the vertical channel. At the same time, the inner surface area of the metal liquid flow channel increases, and more heat loss will occur when the metal liquid flows through the metal liquid flow channel, and the metal liquid is prone to crystallization. The narrowing of the metal liquid flow channel and the generation of metal crystallization will both exacerbate the blockage of the metal liquid flow channel.

[0005] The existing gas atomization preparation devices for metal powders generally have the following defects: (1) The particle size uniformity of the prepared metal powders is poor, the particle size distribution range of the powders is large, and moreover, the powder shape is unstable. When metal powders within a certain mesh range are required, the qualification rate of the metal powders prepared by the existing metal liquid flow atomization nozzles is low; (2) Only a heating device is provided in the gas flow channel, which can only heat the high-pressure inert gas flowing through the gas flow channel, and cannot heat and keep warm the metal liquid flowing through the metal liquid flow channel, resulting in rapid heat dissipation, cooling, and even crystallization of the metal liquid during the process of flowing through the metal liquid flow channel due to the surrounding environment temperature being lower than its own temperature, leading to blockage of the metal liquid flow channel. Summary of the Invention

[0006] The purpose of the present invention is to provide a metal liquid flow atomization nozzle, which can improve the problem of incomplete fragmentation of the liquid flow in the nozzle core and improve the size stability of the fragmented powders.

[0007] The technical solution for achieving the object of the present invention is: a metal melt atomization nozzle, comprising a housing, an annular high-pressure gas flow passage is provided inside the housing, and an annular slit is provided on the bottom wall of the high-pressure gas flow passage to form a high-pressure jet flow passage; one end of the inlet of the high-pressure jet flow passage is communicated with the high-pressure gas flow passage; the diameter of the outlet end of the high-pressure jet flow passage gradually decreases along the gas flow direction to form a tapered contraction port; a metal melt flow passage is penetrated through the housing on the inner ring side of the high-pressure gas flow passage; the extension lines of the tapered contraction port intersect and the intersection point is located on the central axis of the metal melt flow passage; the high-pressure jet flow passage is arranged in a first contracted and then expanded manner from its inlet end to its outlet end (i.e., a Laval structure); the cross-section of the high-pressure jet flow passage is an elliptical ring, and the eccentricity of the elliptical ring of the high-pressure jet flow passage is controlled at 0.24 to 0.45.

[0008] Since the cross-sections of the high-pressure gas nozzles of the existing gas atomization preparation devices for metal powders are all circular rings, the action points of the high-pressure gas for breaking the metal melt are relatively concentrated, the outer surface of the metal melt is broken relatively completely, the powder particle size is relatively small, the core of the metal melt is not broken completely, the formed metal powder particles have different sizes, and moreover, the shape is unstable, mostly strip-shaped, resulting in a relatively large particle size distribution range of the metal powder. However, the present invention firstly proposes to use a high-pressure jet flow passage with an elliptical ring cross-section. The length from each point on the curve between any endpoint of the major axis and any endpoint of the minor axis of the high-pressure jet flow passage to the center point of the ellipse is different. Therefore, after the high-pressure gas is accelerated through the high-pressure jet flow passage with an elliptical ring cross-section, the intersection point of the high-pressure gas ejected from the two endpoints of the major axis of the high-pressure jet flow passage and the intersection point of the central axis of the metal melt flow passage are the farthest from the metal melt flow passage, which is the farthest position for the gas flow to impact the metal melt; the intersection point of the high-pressure gas ejected from the two endpoints of the minor axis of the high-pressure jet flow passage and the intersection point of the central axis of the metal melt flow passage are the closest to the metal melt flow passage, which is the closest position for the gas flow to impact the metal melt; the high-pressure gas flow ejected from the high-pressure jet flow passage can continuously break the metal melt during the process of the metal melt passing through a section of the path from the closest position where the gas flow impacts the metal melt to the farthest position where the gas flow impacts the metal melt, so that the metal melt is completely broken from the outer surface to the core, and the formed metal powder has a more stable shape, a smaller and more concentrated particle size distribution range; moreover, the eccentricity of the ring is 0, and as the eccentricity continuously increases, the improvement effect on the uniformity of the metal powder shows a trend of first increasing and then decreasing. Controlling the eccentricity at 0.24 to 0.45, the improvement of the uniformity of the metal powder reaches a better level, and the yield of the finished product of 35 to 325 mesh fine metal powder reaches more than 85%, which has a significant improvement compared with the existing circular ring slit (the yield of 35 to 325 mesh fine metal powder is 82%).

[0009] Preferably, the metal liquid flow channel is arranged along the central axis of the high-pressure gas flow channel.

[0010] Preferably, the eccentricity of the elliptical ring of the high-pressure jet gas flow channel is controlled between 0.24 and 0.38, which can achieve the best level for improving the uniformity of metal powder, and the yield of fine metal powder with a particle size of 35 to 325 mesh can be further increased to more than 87%.

[0011] Preferably, the high-pressure jet gas flow channel consists of a contraction section, a throat structure, and an expansion section arranged in sequence along the gas flow direction. When high-pressure gas passes through this high-pressure jet gas flow channel, the speed reaches the maximum. Further, the inner and outer walls of the expansion section form an oblique angle, and the oblique angle is 5 to 10°. The angle of this oblique angle should not be too large or too small. If the angle is too small, the gas cannot obtain sufficient speed, and if the angle is too large, certain energy losses will occur. The included angle formed by the angular bisectors of the two side oblique angles of the expansion section is 30 to 45°. If the angle is too large, a large negative pressure will be generated, causing backflow of the liquid flow, and if it is too small, large kinetic energy losses will also be brought.

[0012] Preferably, a liquid guiding pipe assembly mounting hole is provided on the housing, and a liquid guiding pipe assembly is installed in the liquid guiding pipe assembly mounting hole. The liquid guiding pipe assembly includes a liquid guiding pipe arranged along the length direction of the liquid guiding pipe assembly mounting hole. The inner cavity of the liquid guiding pipe is the metal liquid flow channel, and a heating device is arranged on the outer peripheral wall of the liquid guiding pipe. In the present invention, the housing and the liquid guiding pipe are an assembled structure, and a heating device is arranged on the outer peripheral wall of the liquid guiding pipe to preheat the liquid guiding pipe and keep the metal liquid flow in the liquid guiding pipe warm, so as to avoid cooling crystallization when the high-temperature metal liquid flow contacts the liquid guiding pipe, and effectively improve the phenomenon of blockage of the metal liquid flow channel. The liquid guiding pipe assembly mounting hole is a vertical hole, the upper end of the liquid guiding pipe is the metal liquid inlet, and the lower end is the metal liquid outlet. Further, an annular heat dissipation sleeve is coaxially sleeved on the outer peripheral wall of the liquid guiding pipe, and a heating device accommodating cavity for accommodating the heating device is arranged between the heat dissipation sleeve and the liquid guiding pipe. The heating device accommodating cavity is a closed cavity formed by enclosing the heat dissipation sleeve and the liquid guiding pipe. In the present invention, the heat generated by the heating device can be quickly transferred to a farther position through the heat dissipation sleeve, improving the uniformity of heat distribution and the utilization rate of the heating device. Further preferably, the upper end of the heat dissipation sleeve extends upward to the horizontal height position of the metal liquid inlet of the liquid guiding pipe, and can quickly transfer the heat generated by the heating device to the metal liquid inlet. Further, a heat insulation sleeve is arranged in the heat conduction pipe assembly mounting hole, and the inner peripheral wall of the heat insulation sleeve is attached to the outer peripheral wall of the heat dissipation sleeve; the heat insulation sleeve is located at a position close to the upper end of the heat conduction pipe assembly mounting hole in the heat conduction pipe assembly mounting hole to prevent heat from escaping from the upper end. Still further, the lower edge of the heat dissipation sleeve is lower than the lower edge of the heat insulation sleeve, and the outer peripheral wall of the heat dissipation sleeve lower than the heat insulation sleeve is attached to the inner hole wall of the heat conduction pipe assembly mounting hole, so that the excess heat can be transferred to the high-pressure air flow channel through the hole wall of the heat conduction pipe assembly mounting hole (i.e., the housing), heating the high-pressure gas flowing through the high-pressure air flow channel and improving the utilization rate of heat. The lower edge of the liquid guiding pipe is lower than the lower end outlet of the high-pressure jet air flow channel, and an annular gas guiding member is coaxially sleeved outside the liquid guiding pipe around the high-pressure jet air flow channel. The outer peripheral wall of the gas guiding member is a tapered surface that is thick at the top and thin at the bottom, and the tapered surface can guide the air flow ejected from the high-pressure jet air flow channel.

[0013] Preferably, the housing includes an upper housing and a lower housing which are connected up and down. Both the upper housing and the lower housing are annular. The central cavity of the upper housing and the central cavity of the lower housing are connected up and down to form the installation hole for the liquid guide tube assembly. An annular groove is formed on the bottom surface of the upper housing. The annular groove and the upper surface of the lower housing together enclose the high-pressure air flow channel. The lower housing is composed of an inner shell plate and an outer shell plate. The outer peripheral wall of the inner shell plate and the inner peripheral wall of the outer shell plate together enclose the high-pressure jet air flow channel. The inner shell plate and the outer shell plate are respectively fixedly connected to the upper housing, which is convenient for installation, and the inner surface shape of the slit is easy to process. Further, the inner edge of the inner shell plate vertically extends upward along the inner peripheral wall of the upper housing to form an inner edge. The upper end of the inner edge extends to the lower end of the heat insulation sleeve. The inner edge can increase the contact area between the inner shell plate and the upper housing and improve the sealing performance. Description of the Drawings

[0014] Figure 1 is a top view structural schematic diagram of the molten metal flow atomizing nozzle of the present invention, wherein the dotted line is the central axis of the molten metal flow channel, the direction indicated by the solid arrow is the flowing direction of the high-pressure air flow, and the direction indicated by the hollow arrow is the flowing direction of the molten metal flow;

[0015] Figure 2 is along the Figure 1 I-I line in the sectional view structural schematic diagram of the molten metal flow atomizing nozzle of the present invention;

[0016] Figure 3 is along the Figure 2 II-II line in the sectional view structural schematic diagram of the molten metal flow atomizing nozzle of the present invention;

[0017] Figure 4 is Figure 2 the enlarged view of part A in

[0018] Figure 5 is a schematic diagram of the process of the air flow ejected from the high-pressure jet air flow channel (i.e., the slit with an elliptical annular cross-section) breaking the molten metal flow, wherein the dotted line is the central axis of the molten metal flow channel. Embodiments

[0019] The following will make a detailed description of the specific embodiments of the molten metal flow atomizing nozzle of the present invention with reference to the drawings:

[0020] Combined with 1 to Figure 3 and Figure 5, A metal liquid flow atomization nozzle, comprising a housing 10. Inside the housing 10, an annular high-pressure gas flow channel 20 is provided. On the bottom wall of the high-pressure gas flow channel 20, an annular slit forms a high-pressure jet flow channel 40. The inlet end 41 of the high-pressure jet flow channel 40 communicates with the high-pressure gas flow channel 20, and the diameter of the outlet end 42 of the high-pressure jet flow channel 40 gradually decreases along the gas flow direction to form a conical contraction opening; on the housing 10 on the inner ring side of the high-pressure gas flow channel 20, a metal liquid flow channel 30 is penetrated. The extension lines of the conical contraction opening intersect, and the intersection point is located on the central axis of the metal liquid flow channel 30. The slit 40 is arranged to first contract and then expand from its inlet end to its outlet end (i.e., a Laval type structure); the cross-section of the slit 40 is an elliptical ring, and the eccentricity of the elliptical ring of the slit is controlled between 0.24 and 0.45.

[0021] As Figure 5 shown, the present invention adopts a high-pressure jet flow channel 40 with an elliptical ring-shaped cross-section. The length from each point on the curve between any endpoint of the major axis a and any endpoint of the minor axis b of the high-pressure jet flow channel 40 to the center point o of the ellipse is different. Therefore, after the high-pressure gas is accelerated through the high-pressure jet flow channel 40 with an elliptical ring-shaped cross-section, the intersection point of the high-pressure gas ejected from the two endpoints of the major axis a of the high-pressure jet flow channel 40 and the intersection point x of the central axis of the metal liquid flow channel 30 is the farthest from the metal liquid flow channel 30, which is the farthest position x where the gas impacts the metal liquid flow; the intersection point of the high-pressure gas ejected from the two endpoints of the minor axis b of the high-pressure jet flow channel 40 and the intersection point x' of the central axis of the metal liquid flow channel 30 is the closest to the metal liquid flow channel 30, which is the closest position x' where the gas impacts the metal liquid flow; the high-pressure gas flow ejected from the high-pressure jet flow channel 40 can continuously break the metal liquid flow during the process of the metal liquid flow passing through a section of the path from the closest position x' where the gas impacts the metal liquid flow to the farthest position x where the gas impacts the metal liquid flow, so that the metal liquid flow is completely broken from the outer surface to the core, and the formed metal powder has a more stable shape, a smaller and more concentrated uniform particle size distribution range.

[0022] Preferably, the metal liquid flow channel 30 is arranged along the central axis of the high-pressure gas flow channel 20.

[0023] Combined with Figure 2 and Figure 4, the high-pressure jet flow channel 40 is composed of three sections: a contraction section 31, a throat structure 32, and a diffusion section 33 arranged in sequence along the gas flow direction. When high-pressure gas passes through the slit of this Laval structure (i.e., the high-pressure jet flow channel 40), the speed reaches the maximum. Further, the inner and outer walls of the diffusion section 33 form an oblique angle α, and the oblique angle α is 5-10°. This oblique angle should not be too large or too small. If the angle is too small, the gas cannot obtain sufficient speed; if the angle is too large, certain energy losses will occur. The included angle β formed by the angular bisectors of the two side oblique angles of the diffusion section 33 is 30-45°. If the angle is too large, a large negative pressure will be generated, causing liquid flow backflow; if it is too small, a large kinetic energy loss will also be brought.

[0024] In the specific implementation process, as Figure 1 , Figure 2 shown, a high-pressure gas inlet pipe 50 is connected and arranged on the high-pressure gas flow channel 20.

[0025] The inventor of the present invention tested the influence of the elliptical ring eccentricity of the high-pressure jet flow channel 40 of the present invention on the yield of fine metal powder with a mesh size of 35-325. At the same time, a high-pressure jet flow channel structure with a "circular cross-section in the shape of a ring" was used as a comparative example. The specific test results are shown in Table 1 below.

[0026] Table 1

[0027]

[0028] Through experiments, the use of the metal liquid flow atomization nozzle of the present invention has improved the yield in this mesh size range compared with common nozzles in the industry; in particular: when the elliptical ring eccentricity of the high-pressure jet flow channel 40 of the present invention is controlled within the range of 0.24-0.45, the yield of fine powder with a mesh size of 35-325 is above 85%. When the elliptical ring eccentricity of the high-pressure jet flow channel 40 is controlled within the range of 0.24-0.38, the yield of fine powder with a mesh size of 35-325 is above 87%, and the yield in this mesh size range can be increased by up to 10% compared with common nozzles in the industry.

[0029] Preferably, in combination with Figure 1 , Figure 2, a liquid guiding tube assembly mounting hole 100 is provided on the housing 10, and a liquid guiding tube assembly 60 is installed in the liquid guiding tube assembly mounting hole 100. The liquid guiding tube assembly 60 includes a liquid guiding tube 61 arranged along the length direction of the liquid guiding tube assembly mounting hole 100. The inner cavity of the liquid guiding tube 61 is the metal liquid flow channel 30, and a heating device 62 is arranged on the outer peripheral wall of the liquid guiding tube 61. In the present invention, the housing 10 and the liquid guiding tube 61 are an assembled structure, and a heating device 62 is arranged on the outer peripheral wall of the liquid guiding tube 61 to preheat the liquid guiding tube 61 and keep the metal liquid flow in the liquid guiding tube 61 warm, so as to avoid cooling crystallization when the high-temperature metal liquid flow contacts the liquid guiding tube 61, and effectively improve the phenomenon of blockage of the metal liquid flow channel. As Figure 2 shown, the liquid guiding tube assembly mounting hole 100 is a vertical hole. The upper end of the liquid guiding tube 61 is the metal liquid inlet, and the lower end is the metal liquid outlet. Further, in combination with Figure 1 and Figure 2 , an annular heat dissipation sleeve 63 is coaxially sleeved on the outer peripheral wall of the liquid guiding tube 61. A heating device accommodating cavity 64 for accommodating the heating device 62 is arranged between the heat dissipation sleeve 63 and the liquid guiding tube 61. The heating device accommodating cavity 64 is a closed cavity formed by enclosing the heat dissipation sleeve 63 and the liquid guiding tube 61. In the present invention, the heat generated by the heating device can be quickly transferred to a farther position through the heat dissipation sleeve 63, improving the uniformity of heat distribution and the utilization rate of the heating device. Further preferably, as Figure 2 shown, the upper end of the heat dissipation sleeve 63 extends upward to the horizontal height position of the metal liquid inlet of the liquid guiding tube 61, and can quickly transfer the heat generated by the heating device 62 to the metal liquid inlet. Further, in combination with Figure 1 , Figure 2 , a heat insulation sleeve 65 is arranged in the liquid guiding tube assembly mounting hole 100. The inner peripheral wall of the heat insulation sleeve 65 is attached to the outer peripheral wall of the heat dissipation sleeve 63; the heat insulation sleeve 63 is located at a position in the liquid guiding tube assembly mounting hole 100 close to the upper end of the liquid guiding tube assembly mounting hole 100 to prevent heat from leaking from the upper end. Further still, as Figure 2 shown, the lower edge of the heat dissipation sleeve 63 is lower than the lower edge of the heat insulation sleeve 65, and the outer peripheral wall of the heat dissipation sleeve 63 below the heat insulation sleeve 65 is attached to the inner hole wall of the liquid guiding tube assembly mounting hole 100, so that the excess heat can be transferred to the high-pressure air flow channel 20 through the hole wall of the liquid guiding tube assembly mounting hole 100 (i.e., the housing), heating the high-pressure gas flowing through the high-pressure air flow channel 20 and improving the utilization rate of heat. In combination with Figure 2 and Figure 3As shown, the lower edge of the liquid guide tube 61 is lower than the lower outlet of the high-pressure jet flow channel 40. An annular gas guide member 70 is coaxially sleeved outside the liquid guide tube 61 around the high-pressure jet flow channel 40. The outer peripheral wall of the gas guide member 70 is a tapered surface 71 that is thick at the top and thin at the bottom, and the tapered surface 71 can guide the airflow ejected from the high-pressure jet flow channel 40. Of course, the metal liquid flow channel of the present invention can be limited to the specific structure in the drawings, or a metal liquid flow channel structure of "directly opening the metal liquid flow channel 30 on the housing 10" can be adopted.

[0030] Preferably, in combination with Figure 1 , Figure 2 , the housing 10 includes an upper housing 11 and a lower housing 12 that are connected up and down. Both the upper housing 11 and the lower housing 12 are annular; the central cavity of the upper housing 11 and the central cavity of the lower housing 12 are connected up and down to form the liquid guide tube assembly installation hole 100; an annular groove is opened on the bottom surface of the upper housing 11, and the annular groove and the upper surface of the lower housing 12 together enclose the high-pressure air flow channel 20; the lower housing 12 is composed of an inner shell plate 121 and an outer shell plate 122. The outer peripheral wall of the inner shell plate 121 and the inner peripheral wall of the outer shell plate 122 together enclose the high-pressure jet flow channel 40. The inner shell plate 121 and the outer shell plate 122 are respectively fixedly connected to the upper housing 11, which is convenient for installation, and the inner surface shape of the high-pressure jet flow channel 40 is easy to process. Further, in combination with Figure 2 , Figure 3 , the inner edge of the inner shell plate 121 vertically extends upward along the inner peripheral wall of the upper housing 11 to form an inner edge 1210. The upper end of the inner edge 1210 extends to the lower end of the heat insulation sleeve 65. The inner edge 1210 can increase the contact area between the inner shell plate 121 and the upper housing 11 and improve the sealing performance. Of course, the housing 10 of the present invention can be but is not limited to the specific structure in the drawings, and it can adopt the housing structure of an existing metal liquid atomization nozzle.

[0031] For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. A metal liquid flow atomization nozzle, comprising a housing, an annular high-pressure air flow channel is arranged inside the housing, and an annular slit is arranged on the bottom wall of the high-pressure air flow channel to form a high-pressure jet air flow channel; one end of the inlet of the high-pressure jet air flow channel is communicated with the high-pressure air flow channel; the diameter of the outlet end of the high-pressure jet air flow channel gradually decreases along the air flow direction to form a conical contraction port; a metal liquid flow channel is penetrated and arranged on the housing on the inner ring side of the high-pressure air flow channel; the extension lines of the conical contraction port intersect and the intersection point is located on the central axis of the metal liquid flow channel; the high-pressure jet air flow channel is arranged to first contract and then expand from its inlet end to its outlet end; it is characterized in that: The cross-section of the high-pressure jet flow channel is an elliptical ring, and the eccentricity of the elliptical ring of the high-pressure jet flow channel is controlled within 0.24 to 0.45; the high-pressure jet flow channel is composed of a contraction section, a throat structure, and a diffusion section arranged in sequence along the gas flow direction; the inner and outer walls of the diffusion section form an oblique angle, and the oblique angle is 5 to 10°; the included angle formed by the angle bisectors of the two side oblique angles of the diffusion section is 30 to 45°.

2. The metal melt atomization nozzle according to claim 1, wherein: The molten metal flow channel is arranged along the central axis of the high-pressure gas flow channel.

3. The metal melt atomization nozzle according to claim 1, characterized in that: The eccentricity of the elliptical ring of the high-pressure jet flow channel is controlled within 0.24 to 0.

38.

4. The metal melt atomization nozzle according to claim 1, characterized in that: A liquid guide tube assembly installation hole is provided on the housing, and a liquid guide tube assembly is installed in the liquid guide tube assembly installation hole. The liquid guide tube assembly includes a liquid guide tube arranged along the length direction of the liquid guide tube assembly installation hole. The inner cavity of the liquid guide tube is the molten metal flow channel, and a heating device is arranged on the outer peripheral wall of the liquid guide tube.

5. The metal liquid flow atomizing nozzle according to claim 4, wherein: An annular heat dissipation sleeve is coaxially sleeved on the outer peripheral wall of the liquid guide tube. A heating device accommodation cavity for accommodating the heating device is provided between the heat dissipation sleeve and the liquid guide tube. The heating device accommodation cavity is a closed cavity surrounded by the heat dissipation sleeve and the liquid guide tube.

6. The metal melt atomization nozzle according to claim 4, characterized in that: The liquid guide tube assembly installation hole is a vertical hole. The upper end of the liquid guide tube is the molten metal inlet, and the lower end is the molten metal outlet; the lower edge of the liquid guide tube is lower than the lower outlet of the high-pressure jet flow channel. An annular gas guide member is coaxially sleeved outside the liquid guide tube below the high-pressure jet flow channel. The outer peripheral wall of the gas guide member is a tapered surface that is thick at the top and thin at the bottom.

7. The metal liquid flow atomization nozzle according to claim 4, characterized in that: The housing includes an upper housing and a lower housing connected up and down. Both the upper housing and the lower housing are annular; the central cavity of the upper housing and the central cavity of the lower housing are connected up and down to form the liquid guide tube assembly installation hole; an annular groove is provided on the bottom surface of the upper housing, and the annular groove and the upper surface of the lower housing together enclose the high-pressure gas flow channel; the lower housing is composed of an inner shell plate and an outer shell plate, and the outer peripheral wall of the inner shell plate and the inner peripheral wall of the outer shell plate together enclose the high-pressure jet flow channel.

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