Metal powder preparation device

Abstract

The utility model relates to a metal powder preparation device in the technical field of electronic welding material preparation. The metal powder preparation device comprises a pretreatment module and a preparation module. The pretreatment module comprises stirring and heating equipment and a grinding device communicated with an outlet of the stirring and heating equipment; the preparation module comprises a first container communicated with an outlet of the grinding device and an ultrasonic transducer arranged in the first container. According to the metal powder preparation device, preparation of the superfine metal powder can be achieved, preparation of the powder with the specific specification and the superfine granularity can be achieved through the control technology, the granularity is controllable, meanwhile, the prepared metal powder has the advantages of being low in oxygen content and high in yield, metal powder preparation is convenient and fast, equipment is small and convenient, and practicability is high. And the method can be used for producing laboratory-grade superfine powder.

Description

Technical Field

[0001] The present application relates to the technical field of electronic welding material preparation, and in particular to a metal powder preparation device. Background Art

[0002] Solder powder is a bonding material used for interconnecting microelectronic packaging. As electronic end products develop towards miniaturization, thinness, multi-functionality, and integration, the corresponding chip sizes are also shrinking. This places higher demands on chip design and manufacturing, and the internal solder joints are becoming increasingly fine. Consequently, the demand for ultra-fine solder powder, a soldering material for electronic welding, is also increasing.

[0003] The particle size distribution of different types of solder powder are: Type 3 (25μm-45μm), Type 4 (20μm-38μm), Type 5 (15μm-25μm), Type 6 (5μm-15μm), Type 7 (2μm-11μm), Type 8 (2μm-8μm), Type 9 (1μm-5μm), etc. At present, the main preparation methods of solder powder are centrifugal atomization, ultrasonic atomization and gas atomization. The particle size of the raw powder prepared by these methods is normal. Distribution, and the span of powder particle size is large. Commonly used Type 3, Type 4, and Type 5 solder powders can be obtained through sorting. However, for Type 6, Type 7, Type 8, and Type 9 solder powders with finer particle sizes, the powder yield is low, and they are easy to agglomerate, and sorting is also relatively difficult. Therefore, it is difficult to prepare this type of ultrafine solder powder materials with existing mature preparation technologies. At the same time, the market demand for ultrafine solder powder continues to rise. Against this technical background, a breakthrough in ultrafine solder powder preparation technology is imminent. Utility Model Content

[0004] In view of the problems existing in the background technology, the present application provides a metal powder preparation device that can realize the preparation of ultrafine metal powder.

[0005] According to one aspect of the present invention, a metal powder preparation device is provided, comprising a pretreatment module and a preparation module; the pretreatment module comprises a stirring and heating device and a grinding device connected to the outlet of the stirring and heating device; the preparation module comprises a first container connected to the outlet of the grinding device and an ultrasonic transducer arranged in the first container.

[0006] By using the metal powder preparation device in the present technical solution, first, according to the liquidus line T of the metal, a stirring and heating device is used to stir metal raw materials such as solder alloy and heat-resistant oil under high temperature conditions to obtain a uniform mixed metal solution, and then the mixed metal solution is fully ground and crushed using a grinding device. Thereafter, a high-frequency vibrating ultrasonic transducer is used to ultrasonically treat the emulsion obtained by grinding to obtain a mixed solution of metal powder and heat-resistant oil. After the mixed solution is separated, metal powders such as ultrafine solder powder can be obtained, thereby realizing the preparation of ultrafine metal powder.

[0007] In some embodiments of the present invention, the outlet of the grinding device is directed toward the ultrasonic transducer; or

[0008] A second container is provided between the grinding device and the first container. The second container is connected to the grinding device and the first container. An outlet of the second container points to the ultrasonic transducer.

[0009] In some embodiments of the present invention, the stirring and heating equipment includes: a third container; a stirring paddle, which is arranged in the third container; a first driver, which is connected to the stirring paddle; and a heating device, which is arranged on the third container.

[0010] Preferably, the bottom of the third container forms an outlet, and the outlet of the third container is provided with a valve.

[0011] In some embodiments of the present invention, the grinding device includes: a fourth container, the inner bottom of the fourth container forming a first grinding surface; a grinding disc, the grinding disc is arranged in the fourth container, and the side of the grinding disc facing the first grinding surface is formed with a second grinding surface arranged at an interval with the first grinding surface; a second drive, the second drive is connected to the grinding disc; a plurality of through holes are formed on the bottom wall of the fourth container, and the through holes connect the first grinding surface and the outside of the fourth container.

[0012] Preferably, the first grinding surface is a concave conical surface, and the second grinding surface is a convex conical surface adapted to the first grinding surface.

[0013] Preferably, the concave conical surface has a cone angle of 0.5°-8°.

[0014] Preferably, a plurality of linear guide channels are formed on the first grinding surface and / or the second grinding surface, and the guide channels extend from the center of the first grinding surface and / or the second grinding surface to the outer circle.

[0015] Preferably, a plurality of scrapers are connected to the outer periphery of the grinding disc, and the scrapers are spaced apart from the inner bottom of the fourth container.

[0016] Preferably, the scraper protrudes 0.1 mm to 1 mm toward the inner bottom of the fourth container compared to the second grinding surface toward the first grinding surface.

[0017] Preferably, evenly distributed grinding protrusions are formed on the first grinding surface and the second grinding surface respectively.

[0018] Preferably, the diameter of the through hole is 0.8 mm-3 mm.

[0019] Preferably, the thickness of the bottom wall of the fourth container is 15 mm-60 mm.

[0020] Preferably, the fourth container is provided with a heating device.

[0021] In some embodiments of the present invention, the second container forms two or more outlets.

[0022] Preferably, the two or more outlets of the second container are spaced apart and arranged around the ultrasonic transducer.

[0023] Preferably, the outlet of the second container is provided with an on-off switch.

[0024] Preferably, the second container is provided with a heating device.

[0025] In some embodiments of the present invention, the ultrasonic transducer is arranged close to the inner bottom of the first container.

[0026] Preferably, the distance between the ultrasonic transducer and the inner bottom surface of the first container is 2 mm-20 mm.

[0027] Preferably, the bottom of the first container forms an outlet, and the outlet of the first container is provided with a bottom plug.

[0028] Preferably, the first container is provided with a heating device.

[0029] In some embodiments of the present invention, the metal powder preparation device further includes: a collecting container, which is connected to the outlet of the first container. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0031] Figure 1 This is a schematic diagram of the overall structure of the metal powder preparation device of the utility model;

[0032] Figure 2 It is a structural diagram of the fourth container of the utility model;

[0033] Figure 3 It is a structural diagram of the grinding disc of the utility model;

[0034] Figure 4 is a scanning electron microscope image of the SnBi58-Type6 sample prepared in Example 1;

[0035] Figure 5 is a scanning electron microscope image of the SnAg3Cu0.5-Type6 sample prepared in Example 2;

[0036] Figure 6 is a scanning electron microscope image of the SnAg3Cu0.5-Type7 sample prepared in Example 3;

[0037] Figure 7 is a scanning electron microscope image of the SnAg3Cu0.5-Type8 sample prepared in Example 4;

[0038] Figure 8 is a scanning electron microscope image of the SnBi43Sb1.5Ag0.5-Type8 sample prepared in Example 5;

[0039] Figure 9 This is a scanning electron microscope image of the SnBi58-Type9 sample prepared in Example 6.

[0040] The reference numerals in the accompanying drawings represent the following:

[0041] 1. Preprocessing module;

[0042] 11. Stirring and heating device; 111. First driver; 112. Third container; 113. Stirring paddle; 114. Valve; 115. Fourth container cover;

[0043] 12. Second driver; 13. Fourth container; 131. Through hole; 14. Grinding disc; 141. Scraper; 143. Diversion channel;

[0044] 2. Preparation module; 21. Second container; 22. Ultrasonic transducer; 23. First container; 24. Bottom plug;

[0045] 3. Collection container. DETAILED DESCRIPTION

[0046] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0047] When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are merely examples of devices and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0048] In the description of this application, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances. In addition, in the description of this application, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship.

[0049] As electronic terminal products place increasing demands on chip design and manufacturing, higher requirements are being placed on metal powders used as welding materials for microelectronic packaging interconnections, such as solder powder. This is particularly true for the particle size and distribution of solder powder. Currently, solder powders with particle sizes and distributions of Type 3 (25μm-45μm), Type 4 (20μm-38μm), and Type 5 (15μm-25μm) are commonly prepared through centrifugal atomization, ultrasonic atomization, and gas atomization. However, for solder powders with finer particle sizes, Type 6 (5μm-15μm), Type 7 (2μm-11μm), Type 8 (2μm-8μm), and Type 9 (1μm-5μm) suffer from low powder yields, are prone to agglomeration, and are difficult to separate.

[0050] In addition, although ultrafine powders are currently obtained through high-power ultrasonic dispersion and emulsification, as well as filtration and separation processes, high-power ultrasonic waves act directly on the metal mixture, which cannot ensure that all the metal liquid is evenly affected by the ultrasonic waves, thereby affecting the powder output ratio of ultrafine powders. In addition, the action time is long, and the high-power ultrasonic device works for a long time in a high-temperature environment, which affects its lifespan, and therefore cannot operate continuously, resulting in low production efficiency.

[0051] Based on this, the utility model proposes a metal powder preparation device, which can not only realize the preparation of ultrafine metal powder, but also realize the preparation of ultrafine particle size powder of specific specifications through process control. The particle size is controllable. At the same time, the metal powder has low oxygen content and high yield. The metal powder preparation is convenient and fast, the equipment is compact and convenient, and can be used for laboratory-level ultrafine powder production.

[0052] The present application discloses a metal powder preparation device. Figure 1 As shown, the metal powder preparation device includes a pretreatment module 1 and a preparation module 2.

[0053] The pretreatment module 1 includes a stirring and heating device 11 and a grinding device connected to the outlet of the stirring and heating device 11, wherein the stirring and heating device 11 is used to heat and melt the metal raw materials for preparing metal powder and stir and mix the molten metal melt with heat-resistant oil evenly, and the grinding device is used to grind and crush the mixed metal solution of the metal melt and the heat-resistant oil.

[0054] The preparation module 2 includes a first container 23 connected to the outlet of the grinding device and an ultrasonic transducer 22 disposed in the first container 23 , wherein the ultrasonic transducer 22 in the first container 23 is used to perform ultrasonic treatment on the emulsion.

[0055] By using the metal powder preparation device in the present technical solution, first, according to the liquidus line T of the metal, a stirring and heating device 11 is used to stir metal raw materials such as solder alloy and heat-resistant oil under high temperature conditions to obtain a uniform mixed metal solution, and then the mixed metal solution is fully ground and crushed using a grinding device. Thereafter, a high-frequency vibrating ultrasonic transducer 22 is used to ultrasonically treat the emulsion obtained by grinding to obtain a mixed solution of metal powder and heat-resistant oil. After the mixed solution is separated, metal powders such as ultrafine solder powder can be obtained, thereby realizing the preparation of ultrafine metal powder.

[0056] In some embodiments of the present invention, the outlet of the grinding device is directed toward the ultrasonic transducer 22 .

[0057] By directing the outlet of the grinding device toward the ultrasonic transducer 22, the outlet of the first container 23 and the ultrasonic transducer 22 can be closed before or before the grinding device is used to start grinding the mixed metal solution, so that the emulsion is continuously transported to the first container 23 until the emulsion fills at least part of the space in the first container 23, and then the ultrasonic transducer 22 is turned on for ultrasonication to complete the first ultrasonic preparation process; alternatively, the ultrasonic transducer 22 can be turned on before or before the grinding device is used to start grinding the mixed metal solution, so that when the emulsion is transported to the first container 23, the emulsion can directly fall onto the high-frequency vibrating ultrasonic transducer 22, completing the second ultrasonic preparation process.

[0058] Therefore, the present invention can either choose to turn on the ultrasonic transducer 22 for ultrasonication after the emulsion fills part of the space of the first container 23, or choose to turn on the ultrasonic transducer 22 in advance, and the ultrasonic transducer 22 completes ultrasonication while the emulsion continues to enter the first container 23, and the emulsion is continuously output from the first container 23 after ultrasonication, thereby realizing the preparation of ultrafine metal powder under two different processes, and the preparation of ultrafine particle size powder of specific specifications can be achieved by controlling the process.

[0059] In some embodiments of the present invention, Figure 1 As shown, a second container 21 is provided between the grinding device and the first container 23 . The second container 21 connects the grinding device and the first container 23 , and an outlet of the second container 21 points to the ultrasonic transducer 22 .

[0060] By transferring the emulsion through the second container 21, the production rhythm can be better controlled. Moreover, by directing the outlet of the second container 21 toward the ultrasonic transducer 22 instead of directly directing the outlet of the grinding device toward the ultrasonic transducer 22, the flexibility of the structural design and relative arrangement of the grinding device and the first container 23 can be improved.

[0061] In some embodiments of the present invention, Figure 1 As shown, the second container 21 has more than two outlets.

[0062] By increasing the number of outlets of the second container 21 , the emulsion can be made to land more evenly on the surface of the ultrasonic transducer 22 , thereby improving the ultrasonic effect of the ultrasonic transducer 22 on the emulsion.

[0063] In some embodiments of the present invention, Figure 1 As shown, the two or more outlets of the second container 21 are arranged at intervals around the ultrasonic transducer 22 , which can further improve the uniformity of the emulsion landing on the surface of the ultrasonic transducer 22 .

[0064] Preferably, the two or more outlets of the second container 21 are evenly arranged around the ultrasonic transducer 22 .

[0065] It should be noted that in other embodiments of the present invention, when the outlet of the grinding device is directly directed to the ultrasonic transducer 22, the outlet of the grinding device can be set as a plurality of small holes, and the small holes are grouped. Each group of small holes is indirectly directed to the ultrasonic transducer 22 through a pipe, and the outlets of the multiple pipes are spaced and evenly arranged around the ultrasonic transducer 22 to achieve uniform ultrasound of the emulsion.

[0066] In some embodiments of the present invention, the outlet of the second container 21 is provided with an on-off switch (not shown), which can control the timing and speed of the second container 21 conveying the emulsion to the first container 23. For example, when performing the above-mentioned first ultrasonic preparation process, the on-off switch can be turned off first. After the emulsion received in the second container 21 reaches a certain amount, the on-off switch can be turned on to centrally convey the emulsion to the first container 23. Alternatively, when performing the above-mentioned second ultrasonic preparation process, the on-off switch can be kept on and the flow rate can be adjusted so that the second container 21 continuously receives the emulsion and the emulsion continuously falls on the ultrasonic transducer 22 at a certain flow rate.

[0067] Furthermore, when the second container 21 has multiple outlets, an on-off switch can be optionally set at each outlet of the second container 21, or multiple outlets of the second container 21 are gathered together near one side of the second container 21, and an on-off switch is centrally set at the gathering point.

[0068] It should be noted that in other embodiments of the present invention, when the small hole of the grinding device points to the ultrasonic transducer 22 through the outlet of the above-mentioned pipeline, the on-off switch can also be set at the outlet of the pipeline. In addition, it is only necessary to set an emulsion temporary storage space on the side of the grinding device where the on-off switch of the pipeline is located, so that the emulsion can be centrally transported to the first container 23.

[0069] In some embodiments of the present invention, a heating device (not shown) is provided on the second container 21. The heating device on the second container 21 can heat and keep the emulsion warm to prevent the temperature of the emulsion from dropping after leaving the grinding device, which would affect the subsequent ultrasonic effect on the emulsion.

[0070] In some embodiments of the present invention, Figure 1 As shown, the stirring and heating device 11 includes a third container 112, a stirring paddle 113, a first driver 111 and a heating device.

[0071] The stirring paddle 113 is disposed in the third container 112 , and the first driver 111 is connected to the stirring paddle 113 . By turning on the first driver 111 , the stirring paddle 113 can be driven directly or indirectly to stir in the third container 112 .

[0072] The heating device is provided on the third container 112 , and the heating device on the third container 112 can melt the metal added into the third container 112 into a melt, and the melt and the temperature-resistant oil are stirred and evenly mixed by the stirring paddle 113 to obtain a mixed metal solution.

[0073] Furthermore, the first driver 111 includes but is not limited to power machinery such as an electric motor, and the output shaft of the first driver 111 can be coaxially connected to the stirring paddle 113 or indirectly connected through a transmission mechanism.

[0074] In some embodiments of the present invention, Figure 1 As shown, an outlet is formed at the bottom of the third container 112, and a valve 114 is provided at the outlet of the third container 112. By arranging the outlet and the valve 114 at the bottom of the third container 112, the metal can be fully melted in the third container 112 and the metal melt and the heat-resistant oil can be evenly stirred to obtain a mixed metal solution. Then, the valve 114 is opened to conveniently and efficiently transport the mixed metal solution to the grinding device for subsequent grinding and crushing processes.

[0075] In this embodiment, the valve 114 may specifically adopt a butterfly valve structure.

[0076] In other embodiments of the present invention, according to actual process requirements, an outlet can be provided on the side wall or top of the third container 112 to transport the raw materials to the grinding device by tilting or pouring the third container 112, which is not limited here.

[0077] In some embodiments of the present invention, Figure 1 As shown, the grinding device includes a fourth container 13 , a grinding disc 14 and a second drive 12 .

[0078] The inner bottom surface of the fourth container 13 forms a first grinding surface; the grinding disc 14 is arranged in the fourth container 13, and the side of the grinding disc 14 facing the first grinding surface forms a second grinding surface spaced apart from the first grinding surface; the second driver 12 is connected to the grinding disc 14.

[0079] A plurality of through holes 131 are formed on the bottom wall of the fourth container 13 , and the through holes 131 communicate with the first grinding surface and the outside of the fourth container 13 .

[0080] After the mixed metal solution enters the fourth container 13, the mixed metal solution will continue to flow into the gap between the first grinding surface and the second grinding surface. The second driver 12 can drive the grinding disc 14 to rotate, so that the second grinding surface rotates relative to the first grinding surface, and the mixed metal solution can be continuously ground and crushed. The emulsion formed after the grinding and crushing can be directly transported to the first container 23 through the through hole 131 without setting the second container 21, or it can be transported to the second container 21 first and then transferred to the first container 23 if the second container 21 is set.

[0081] Furthermore, the diameter of the through hole 131 is 0.8 mm to 3 mm, and can be reasonably designed according to the type (particle size and particle size distribution) of the metal powder.

[0082] Furthermore, the second driver 12 includes but is not limited to a power machine such as an electric motor, and the output shaft of the second driver 12 can be coaxially connected to the grinding disc 14 or indirectly connected through a transmission mechanism.

[0083] In some embodiments of the present invention, Figure 2 and Figure 3 As shown, the first grinding surface is a concave conical surface, and the second grinding surface is a convex conical surface adapted to the first grinding surface.

[0084] By setting a concave conical surface as the first grinding surface and a convex conical surface as the second grinding surface, the grinding area can be increased, the grinding and crushing efficiency and grinding and crushing effect can be improved, and the mixed metal solution can naturally converge to the middle of the first grinding surface and the second grinding surface, which is beneficial to further improve the grinding and crushing effect and facilitate the natural discharge of the fully ground and crushed emulsion through the through hole 131.

[0085] Furthermore, the cone angle of the concave conical surface is 0.5°-8°. It should be noted that the cone angle of the concave conical surface is not particularly limited. People in this field can make reasonable choices according to actual needs. As some specific examples, the cone angle of the concave conical surface can be 0.5°, 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8°, etc.

[0086] In some embodiments of the present invention, Figure 3 As shown, a plurality of linear guide channels 143 are formed on the first grinding surface and / or the second grinding surface, and the guide channels 143 extend from the center of the first grinding surface and / or the second grinding surface to the outer circle.

[0087] The mixed metal solution can flow from the periphery to the center through the guide channel 143 , thereby improving the uniform distribution of the mixed metal solution in the gap between the first grinding surface and the second grinding surface.

[0088] It should be noted that the guide channel 143 can be linear or arc-shaped. When the guide channel 143 is arc-shaped, the arc-shaped opening can be set in the same direction as the rotation direction of the grinding disc 14.

[0089] Preferably, the guide channel 143 is opened on the second grinding surface, that is, the guide channel 143 is provided on the grinding disc 14 .

[0090] Preferably, the plurality of guide channels 143 are evenly distributed around the axis of the grinding disc 14 .

[0091] In some embodiments of the present invention, Figure 3 As shown, a plurality of scrapers 141 are connected to the outer periphery of the grinding disc 14 , and a gap is arranged between the scrapers 141 and the inner bottom of the fourth container 13 .

[0092] The scraper 141 can extend the mixed metal solution dispersed on the edge of the bottom surface of the fourth container 13, so that the mixed metal solution is evenly distributed on the bottom of the fourth container 13 and flows toward the center along the slope.

[0093] It should be noted that the side of the scraper 141 close to the first grinding surface may have the same inclination angle as the first grinding surface (second grinding surface).

[0094] Furthermore, the number of the scrapers 141 can be one, two, three, four, five or six, etc.

[0095] Furthermore, the scraper 141 protrudes toward the inner bottom of the fourth container 13 by 0.1 mm to 1 mm compared to the second grinding surface toward the first grinding surface.

[0096] In some embodiments of the present invention, evenly distributed grinding protrusions (not shown) are formed on the first grinding surface and the second grinding surface respectively. The mixed metal solution can be better ground and crushed by the grinding protrusions.

[0097] It should be noted that the grinding protrusions can be an integrally formed structure made of the same material as the grinding disc 14 (fourth container 13), that is, the surface of the grinding disc 14 (fourth container 13) has a certain roughness to form grinding protrusions for grinding and crushing.

[0098] In the present invention, the surface roughness of the grinding disc 14 and the size of the gap between the second grinding surface of the grinding disc 14 and the first grinding surface of the fourth container 13 can be reasonably designed according to the type of metal powder to be prepared.

[0099] In some embodiments of the present invention, the thickness of the bottom wall of the fourth container 13 is 15 mm-60 mm. It should be understood that the length of the through hole 131 is 15 mm-60 mm.

[0100] In some embodiments of the present invention, a heating device (not shown) is provided on the fourth container 13. The heating device on the fourth container 13 can heat and keep the mixed metal solution warm, thereby preventing the temperature of the mixed metal solution from dropping after leaving the third container 112 (stirring and heating device 11), thereby affecting the grinding and crushing effect of the mixed metal solution.

[0101] In some embodiments of the present invention, Figure 1 As shown, the ultrasonic transducer 22 is close to the inner bottom surface of the first container 23.

[0102] Preferably, the outlet of the grinding device or the outlet of the second container 21 is directed toward the upper middle portion of the ultrasonic transducer 22 .

[0103] It should be noted that in the first ultrasonic preparation process described above, when the emulsion that requires ultrasound enters the first container, the ultrasonic transducer is turned on, and the amount of emulsion entering the first container should not be too much or too little, so as to facilitate complete ultrasound of the emulsion (too much may result in insufficient ultrasound and insufficient energy; too little may not cover the ultrasonic head of the ultrasonic transducer, and the ultrasonic energy may evaporate into the atmosphere without contacting the emulsion).

[0104] Furthermore, the distance between the ultrasonic transducer 22 and the inner bottom surface of the first container 23 is 2 mm-20 mm.

[0105] In some embodiments of the present invention, Figure 1 As shown, an outlet is formed at the bottom of the first container 23, and a bottom plug 24 is provided at the outlet of the first container 23. By arranging the outlet and the bottom plug 24 at the bottom of the first container 23, after completing the above-mentioned first ultrasonic preparation process and fully ultrasonicating the emulsion in the first container 23, the bottom plug 24 can be opened to conveniently and efficiently transport the mixed solution of metal powder and heat-resistant oil out, or when performing the above-mentioned second ultrasonic preparation process, the bottom plug 24 can be opened in advance so that the emulsion is directly discharged from the outlet of the first container 23 after being ultrasonicated by the ultrasonic transducer 22, so as to facilitate the subsequent separation of the metal powder.

[0106] Specifically, the bottom surface of the bottom plug 24 in the present invention is just flush with the first container 23 and serves as a part of the first container 23 during the reaction process.

[0107] In other embodiments of the present invention, according to actual process requirements, an outlet may be provided on the side wall or top of the first container 23 to release the mixed solution of metal powder and heat-resistant oil by tilting or pouring the first container 23.

[0108] In some embodiments of the present invention, the volume of the first container 23 is 2 to 10 times the volume of the second container 21, ensuring that the emulsion held by the second container 21 can submerge part of the length of the ultrasonic transducer 22 in the first container 23 without excessively filling the first container 23.

[0109] In some embodiments of the present invention, a heating device is provided on the first container 23. The heating device on the first container 23 can heat and keep the emulsion transported into the first container 23 warm, thereby preventing the temperature of the emulsion from dropping after leaving the grinding device or the second container 21, thereby affecting the ultrasonic effect on the emulsion.

[0110] In some embodiments of the present invention, Figure 1As shown, the metal powder preparation device also includes a collecting container 3, which is connected to the outlet of the first container 23. The mixed solution of metal powder and heat-resistant oil can be collected through the collecting container 3 to facilitate the subsequent separation of the metal powder.

[0111] In some embodiments of the present invention, the third container 112, the fourth container 13, the second container 21, the first container 23 and the collection container 3 are arranged in sequence from top to bottom, and the transfer of materials in each process can be completed by using gravitational potential energy.

[0112] In some embodiments of the present invention, two or more groups of stirring and heating devices 11 (third containers 112 ) may be provided above the grinding device (fourth container 13 ), and the two or more groups of third containers 112 are spaced apart around the axis of the fourth container 13 .

[0113] For example, the number of the stirring and heating devices 11 can be 2, 3, 4, 5, etc.

[0114] In some embodiments of the present invention, Figure 1 As shown, the top opening of the fourth container 13 is sealed by the fourth container cover 115, and the third container 112 is placed on the flange of the fourth container cover 115. The flanges equal in number to the stirring and heating equipment 11 are evenly distributed above the fourth container cover 115 for placing each third container 112, and a motor hole for driving the grinding disc 14 is set in the center of the fourth container cover 115.

[0115] Preferably, the outlet of the third container 112 deviates from the middle area of ​​the fourth container 13, so that the mixed metal solution flowing from the third container 112 to the fourth container 13 can fall on the scraper 141, be better extended by the scraper 141 and flow toward the center along the slope of the bottom of the fourth container 13.

[0116] In other embodiments of the present invention, Figure 1 As shown, the third container 112 is an annular cylindrical barrel with flanges at both ends. The upper flange is connected to the flange seat of the motor (first driver 111), and the lower flange is connected to the butterfly valve. The butterfly valve controls the opening or closing of the bottom of the third container 112. When the butterfly valve is closed, the butterfly valve is equivalent to the bottom of the third container 112, and metal and heat-resistant oil can be contained at this time. When the butterfly valve is opened, the third container 112 and the fourth container 13 are connected, and the uniform mixed metal solution formed in the third container 112 flows into the edges of the fourth container 13.

[0117] In some embodiments of the present invention, the first container 23 , the second container 21 , the third container 112 and the fourth container 13 are preferably high-temperature resistant crucibles.

[0118] In addition, the collecting container 3 can also be a high-temperature resistant crucible.

[0119] Specifically, in the present invention, the second container 21 may be a three-way funnel, and the first container 23 may be a three-mouth ultrasonic crucible.

[0120] In some embodiments of the present invention, the heating devices on the first container 23, the second container 21, the third container 112 and the fourth container 13 include but are not limited to electric heating wires, heating sleeves or high-frequency electromagnetic heating.

[0121] The first container 23 , the second container 21 , the third container 112 and the fourth container 13 may be heated by a heating device according to the liquidus line T of the metal alloy, specifically to a temperature of T+20° C. to T+80° C.

[0122] The present invention utilizes the above-mentioned metal powder preparation device to prepare metal powder, comprising the following steps:

[0123] 1) Add metal and heat-resistant oil to the stirring and heating device 11, heat to a specified temperature and keep it warm for a period of time, then stir evenly to obtain a mixed metal solution.

[0124] 2) Turn on the grinding device and transport the mixed metal solution to the grinding device for grinding and crushing. After the mixed metal solution is ground and crushed, an emulsion is formed.

[0125] 3) After a certain amount of the emulsion is transferred to the first container 23, the emulsion is ultrasonically processed by the ultrasonic transducer 22 in the first container 23 for a period of time, or the emulsion is directly transferred to the first container and falls directly onto the ultrasonic transducer and then falls naturally after being ultrasonicated, thereby obtaining a mixed solution of metal powder and heat-resistant oil.

[0126] In this step, the ultrasonic transducer can ultrasonicate the emulsion in two different processes, and the preparation of ultrafine particle size powder of specific specifications can be achieved by controlling the process.

[0127] 4) Separating the mixed solution to obtain metal powder.

[0128] In some embodiments of the present invention, the heat-resistant oil is selected from one or more of peanut oil, castor oil, olive oil, silicone oil, and rosin.

[0129] In some embodiments of the present invention, the metal includes but is not limited to an alloy or a pure metal, for example, the alloy is a tin alloy.

[0130] Furthermore, the components of the tin alloy include Sn and one or more selected from Pb, Sb, Bi, Cu, Ag, and In.

[0131] In some embodiments of the present invention, the metal powder preparation process is carried out in an atmosphere of protective gas. Preferably, when each process is carried out in the third container, the fourth container, the second container and the first container, nitrogen or a rare gas such as argon and other protective gases are continuously introduced into each container to more effectively control the oxygen content of the metal powder.

[0132] Specifically, in the present invention, according to the different particle sizes of the produced ultrafine metal powder, the preparation methods of the metal powder using the metal powder preparation device of the present invention include the following two methods.

[0133] The first preparation method

[0134] First, you need to close the valve 114, then add metal and heat-resistant oil into the third container 112, turn on the heating function of the third container 112, heat it to a certain temperature (T+20℃-T+80℃), turn on the power of the first driver 111, adjust the speed of the first driver 111 to 500rpm to 8000rpm, and stir for 2-4 minutes to allow the metal and heat-resistant oil to form a uniform mixed metal solution.

[0135] After stirring stops, the second driver 12 is started, which drives the grinding disc 14 to rotate at a speed of 300 rpm-6000 rpm. The on-off switch of the three-way funnel is turned off, the heating functions of the fourth container 13 and the three-way funnel are turned on, and the valve 114 above the fourth container cover 115 is opened. The uniformly mixed metal solution flows from the third container 112 into the fourth container 13. Under the action of the scraper 141, the uniformly mixed metal solution is evenly dispersed on the bottom surface of the fourth container 13. At the same time, due to the certain slope of the bottom surface of the grinding disc 14, the uniformly mixed metal solution slowly converges to the center through the guide channel 143 on the bottom surface of the grinding disc 14 and the gap between the fourth container 13 and the grinding disc 14. During this process, the grinding disc 14 and the fourth container 13 grind and crush the uniformly mixed metal solution. The emulsion obtained by grinding naturally flows into the three-way funnel through the through hole 131 at the bottom of the fourth container 13.

[0136] When the emulsion in the three-way funnel reaches a certain amount, the heating and heat preservation function of the three-way funnel and the three-mouth ultrasonic crucible is turned on, and their temperatures are set and monitored. The three-way funnel and the three-mouth ultrasonic crucible are set to corresponding temperatures (T+20°C to T+80°C) according to the liquidus line T of the metal. The specific temperature needs to be determined according to the properties of the metal. The bottom plug 24 is tightly closed, the three-way funnel switch is turned on, and then the emulsion enters the three-mouth ultrasonic crucible through the three-way funnel. After all the emulsion in the three-way funnel enters the three-mouth ultrasonic crucible, the three-way funnel switch is turned off.

[0137] When the temperature of the emulsion inside the three ultrasonic crucibles reaches the indicator line (not shown), the ultrasonic transducer 22 is turned on, the frequency is set to 10-50kHz, and the ultrasonic time is 3-15 minutes. After the time is reached, the ultrasound is stopped, the bottom plug 24 is opened, the solution in the three ultrasonic crucibles is collected and naturally cooled to obtain a mixed solution of ultrafine metal powder and heat-resistant oil. The metal powder and heat-resistant oil are then separated. Separation methods include static precipitation, centrifugation, filtration, etc. After separation, the prepared ultrafine powder needs to be cleaned, and cleaning agents include anhydrous ethanol, acetone, and trichloroethylene.

[0138] The second preparation method

[0139] First, you need to close the valve 114, then add metal and heat-resistant oil into the third container 112, turn on the heating function of the third container 112, heat it to a certain temperature (T+20℃-T+80℃), turn on the power of the first driver 111, adjust the speed of the first driver 111 to 500rpm to 8000rpm, and stir for 2-4 minutes to allow the metal and heat-resistant oil to form a uniform mixed metal solution.

[0140] After stirring stops, start the second driver 12, which drives the rotating grinding disc to rotate at a speed of 300 rpm-6000 rpm. Turn on the heating function of the fourth container 13 and the three-way funnel, open the bottom plug 24, start the ultrasonic transducer 22, set the frequency to 40-100 kHz, connect the fourth container 13 on the top of the three-way funnel, and connect the three ultrasonic crucibles on the bottom. The on-off switch on the top of the three-way funnel is turned on and connected to the three ultrasonic crucibles. Open the valve 114 switch above the fourth container cover 115, and the uniformly mixed metal solution obtained after stirring flows from the third container 112 into the fourth container 13. Under the action of the scraper 141, the uniformly mixed metal solution is evenly dispersed on the bottom surface of the fourth container 13. At the same time, since the bottom surface of the grinding disk 14 has a certain slope, the uniformly mixed metal solution slowly converges to the center through the guide channel 143 on the bottom surface of the grinding disk 14 and the gap between the fourth container 13 and the grinding disk 14. During this process, the grinding disk 14 and the fourth container 13 grind and crush the uniformly mixed metal solution. The emulsion obtained by grinding naturally flows into the three-way funnel through the through hole 131 at the bottom of the fourth container 13, and the flow rate is stable and uniform.

[0141] The emulsion flows out stably through the outlets on both sides of the lower end of the three-way funnel. The outflowing emulsion falls on the ultrasonic head of the ultrasonic transducer 22 under the action of gravitational potential energy. After passing through the ultrasonic head, a mixed solution of ultrafine powder and heat-resistant oil is obtained, which flows out through the outlet at the bottom of the three ultrasonic crucibles. This process can be carried out stably and continuously. The collection container 3 collects the solution in the three ultrasonic crucibles and cools it naturally to obtain a mixed solution of ultrafine metal powder and heat-resistant oil. The metal powder and the heat-resistant oil are then separated. Separation methods include static precipitation, centrifugal separation, filtration, etc. After separation, the prepared ultrafine powder needs to be cleaned, and the cleaning agent includes anhydrous ethanol, acetone, and trichloroethylene.

[0142] The following will further illustrate the method of preparing metal powder using the above-mentioned metal powder preparation device in this application with reference to specific examples. Each example is carried out in a nitrogen protective gas atmosphere.

[0143] Example 1

[0144] The first preparation method is to prepare SnBi58 ultrafine solder powder

[0145] SnBi58 and heat-resistant oil are added to the third container in a volume ratio of 1:12, the temperature is set to 190°C, the speed of the first driver is 1500 rpm, and a uniform mixed solution is formed after stirring. Then it enters the fourth container through the valve, the speed of the second driver is 1000 rpm, and a 1.5 mm hole is opened at the bottom of the fourth container. After grinding, an emulsion is formed and enters the three-mouth ultrasonic crucible through a three-way funnel. The ultrasonic transducer is set to a frequency of 15 kHz and an ultrasonic time of 8 minutes. After completion, it enters the collection container from the bottom of the three crucibles and is cooled to obtain a mixed solution of ultrafine powder and heat-resistant oil. Ultrafine powder is obtained by static precipitation, and then ultrafine solder powder is obtained by washing with acetone. The powder with particle size T6 (5-15 μm) accounts for 93% after testing, the oxygen content is 280 ppm, the sphericity is good, and it meets the standard technical indicators of the electronics industry. The scanning electron microscope image is as follows Figure 4 shown.

[0146] Example 2

[0147] The first preparation method is to prepare SnAg3Cu0.5 ultrafine solder powder

[0148] SnAg3Cu0.5 and heat-resistant oil are added to the third container in a volume ratio of 1:13, the temperature is set to 275°C, the speed of the first driver is 2000rmp, and a uniform mixed solution is formed after stirring. Then it enters the fourth container through the valve, the speed of the second driver is 1000rmp, and a 1.3 mm hole is opened at the bottom of the fourth container. After grinding, an emulsion is formed and enters the three-mouth ultrasonic crucible through a three-way funnel. The ultrasonic transducer is set to a frequency of 16kHz and an ultrasonic time of 8 minutes. After completion, it enters the collection container from the bottom of the three crucibles and is cooled to obtain a mixed solution of ultrafine powder and heat-resistant oil. Ultrafine powder is obtained by static precipitation, and then ultrafine solder powder is obtained by washing with acetone. After testing, the powder with particle size T6 (5-15μm) accounts for 95%, the oxygen content is 260ppm, the sphericity is good, and it meets the standard technical indicators of the electronics industry. The scanning electron microscope image is as follows Figure 5 shown.

[0149] Example 3

[0150] The first preparation method is to prepare SnAg3Cu0.5 ultrafine solder powder

[0151] SnAg3Cu0.5 and heat-resistant oil are added to the third container in a volume ratio of 1:14, the temperature is set to 278°C, the speed of the first driver is 2200 rpm, and a uniform mixed solution is formed after stirring. Then it enters the fourth container through the valve, the speed of the second driver is 900 rpm, and a 1.2 mm hole is opened at the bottom of the fourth container. After grinding, an emulsion is formed and enters the three-mouth ultrasonic crucible through a three-way funnel. The ultrasonic transducer is set to a frequency of 16 kHz and an ultrasonic time of 10 minutes. After completion, it enters the collection container from the bottom of the three crucibles and is cooled to obtain a mixed solution of ultrafine powder and heat-resistant oil. Ultrafine powder is obtained by static precipitation, and then ultrafine solder powder is obtained by washing with acetone. After testing, the powder with a particle size of T7 (2-11 μm) accounts for 94%, the oxygen content is 350 ppm, the sphericity is good, and it meets the standard technical indicators of the electronics industry. The scanning electron microscope image is as follows Figure 6 shown.

[0152] Example 4

[0153] The second preparation method is to prepare SnAg3Cu0.5 ultrafine solder powder

[0154] SnAg3Cu0.5 and heat-resistant oil were added to the third container in a volume ratio of 1:14, the temperature was set at 280°C, the speed of the first driver was 2500 rpm, and a uniform mixed solution was formed after stirring. The mixed solution then entered the fourth container through a valve, the speed of the second driver was 850 rpm, and a 1.2 mm through-hole was opened at the bottom of the fourth container. After grinding, an emulsion was formed and naturally flowed into the three-way funnel through the through-hole at the bottom of the fourth container. The flow rate was stable and uniform. The emulsion flows out steadily through the outlets on both sides of the lower end of the three-way funnel. The outflowing emulsion falls on the ultrasonic head of the ultrasonic transducer under the action of gravitational potential energy. The ultrasonic transducer is set to a frequency of 68kHz. After passing through the ultrasonic head, a mixed solution of ultrafine powder and heat-resistant oil is obtained. The emulsion flows out through the outlet at the bottom of the three-mouth ultrasonic crucible, enters the collection container and is cooled to obtain a mixed solution of ultrafine powder and heat-resistant oil. The ultrafine powder is obtained by filtration separation, and then washed with acetone to obtain ultrafine solder powder. The powder with a particle size of T8 (2-8μm) accounts for 93% after testing, the oxygen content is 480ppm, the sphericity is good, and it meets the standard technical indicators of the electronics industry. The scanning electron microscope image is as follows Figure 7 shown.

[0155] Example 5

[0156] The second preparation method is to prepare ultrafine solder powder of SnBi43Sb1.5Ag0.5

[0157] SnBi43Sb1.5Ag0.5 and heat-resistant oil were added to the third container at a volume ratio of 1:14. The temperature was set at 200°C and the speed of the first driver was 2500 rpm. After stirring, a uniform mixed solution was formed, which then entered the fourth container through a valve. The speed of the second driver was 850 rpm. A 1.2 mm through-hole was opened at the bottom of the fourth container. After grinding, an emulsion was formed, which naturally flowed into the three-way funnel through the through-hole at the bottom of the fourth container with a stable and uniform flow rate. The emulsion flows out steadily through the outlets on both sides of the lower end of the three-way funnel. The outflowing emulsion falls on the ultrasonic head of the ultrasonic transducer under the action of gravitational potential energy. The ultrasonic transducer is set to a frequency of 68kHz. After passing through the ultrasonic head, a mixed solution of ultrafine powder and heat-resistant oil is obtained. The emulsion flows out through the outlet at the bottom of the three-mouth ultrasonic crucible, enters the collection container and is cooled to obtain a mixed solution of ultrafine powder and heat-resistant oil. The ultrafine powder is obtained by filtration separation, and then washed with acetone to obtain ultrafine solder powder. The powder with a particle size of T8 (2-8μm) accounts for 92% after testing, the oxygen content is 470ppm, the sphericity is good, and it meets the standard technical indicators of the electronics industry. The scanning electron microscope image is as follows Figure 8 shown.

[0158] Example 6

[0159] The second preparation method is to prepare ultrafine solder powder of SnBi58

[0160] SnBi58 and heat-resistant oil were added to the third container in a volume ratio of 1:14. The temperature was set at 195°C and the speed of the first driver was 3000 rpm. After stirring, a uniform mixed solution was formed. The mixed solution then entered the fourth container through a valve. The speed of the second driver was 800 rpm. A 1.1 mm hole was opened at the bottom of the fourth container. After grinding, an emulsion was formed and naturally flowed into the three-way funnel through the small hole at the bottom of the grinding crucible. The flow rate was stable and uniform. The emulsion flows out steadily through the outlets on both sides of the lower end of the three-way funnel. The outflowing emulsion falls on the ultrasonic head of the ultrasonic transducer under the action of gravitational potential energy. The ultrasonic transducer is set to a frequency of 69kHz. After passing through the ultrasonic head, a mixed solution of ultrafine powder and heat-resistant oil is obtained. The emulsion flows out through the outlet at the bottom of the three-mouth ultrasonic crucible, enters the collection container and is cooled to obtain a mixed solution of ultrafine powder and heat-resistant oil. The ultrafine powder is obtained by filtration separation, and then washed with acetone to obtain ultrafine solder powder. The powder with a particle size of T9 (1-5μm) accounts for 92% after testing, the oxygen content is 650ppm, the sphericity is good, and it meets the standard technical indicators of the electronics industry. The scanning electron microscope image is as follows Figure 9 shown.

[0161] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A metal powder preparation device, characterized in that: It includes a pretreatment module and a preparation module; The pretreatment module includes a stirring and heating device and a grinding device connected to the outlet of the stirring and heating device; The preparation module includes a first container connected to the outlet of the grinding device and an ultrasonic transducer arranged in the first container.

2. The metal powder preparation device according to claim 1, characterized in that: The outlet of the grinding device is directed toward the ultrasonic transducer; or A second container is provided between the grinding device and the first container. The second container is connected to the grinding device and the first container. An outlet of the second container points to the ultrasonic transducer.

3. The metal powder preparation device according to claim 1, characterized in that: The stirring and heating equipment comprises: third container; a stirring paddle, the stirring paddle being disposed in the third container; a first driver connected to the stirring paddle; A heating device is provided on the third container.

4. The metal powder preparation device according to claim 3, characterized in that: An outlet is formed at the bottom of the third container, and a valve is provided at the outlet of the third container.

5. The metal powder preparation device according to claim 1, characterized in that: The grinding device comprises: a fourth container, wherein the inner bottom of the fourth container forms a first grinding surface; a grinding disc, the grinding disc being disposed in the fourth container, the grinding disc having a second grinding surface formed on a side facing the first grinding surface and spaced apart from the first grinding surface; a second driver connected to the grinding disc; A plurality of through holes are formed on the bottom wall of the fourth container, and the through holes communicate with the first grinding surface and the outside of the fourth container.

6. The metal powder preparation device according to claim 5, characterized in that: The first grinding surface and the second grinding surface are respectively formed with uniformly distributed grinding protrusions.

7. The metal powder preparation device according to claim 5, characterized in that: The diameter of the through hole is 0.8 mm-3 mm.

8. The metal powder preparation device according to claim 5, characterized in that: The thickness of the bottom wall of the fourth container is 15 mm-60 mm.

9. The metal powder preparation device according to claim 5, characterized in that: The fourth container is provided with a heating device.

10. The metal powder preparation device according to claim 5, characterized in that: The first grinding surface is a concave conical surface, and the second grinding surface is a convex conical surface adapted to the first grinding surface.

11. The metal powder preparation device according to claim 10, characterized in that: The concave conical surface has a cone angle of 0.5°-8°.

12. The metal powder preparation device according to claim 5, characterized in that: A plurality of linear guide channels are formed on the first grinding surface and / or the second grinding surface, and the guide channels extend from the center of the first grinding surface and / or the second grinding surface to the outer circle.

13. The metal powder preparation device according to claim 5, characterized in that: A plurality of scrapers are connected to the outer periphery of the grinding disc, and the scrapers are spaced apart from the inner bottom of the fourth container.

14. The metal powder preparation device according to claim 13, wherein: The scraper protrudes toward the inner bottom of the fourth container by 0.1 mm to 1 mm compared to the second grinding surface toward the first grinding surface.

15. The metal powder preparation device according to claim 2, characterized in that: The second container has two or more outlets.

16. The metal powder preparation device according to claim 15, characterized in that: The two or more outlets of the second container are spaced apart and arranged around the ultrasonic transducer.

17. The metal powder preparation device according to claim 15, characterized in that: An on-off switch is provided at the outlet of the second container.

18. The metal powder preparation device according to claim 15, characterized in that: The second container is provided with a heating device.

19. The metal powder preparation device according to claim 1, characterized in that: The ultrasonic transducer is arranged close to the inner bottom of the first container.

20. The metal powder preparation device according to claim 19, wherein: The distance between the ultrasonic transducer and the inner bottom surface of the first container is 2 mm-20 mm.

21. The metal powder preparation device according to claim 19, characterized in that: The bottom of the first container forms an outlet, and the outlet of the first container is provided with a bottom plug.

22. The metal powder preparation device according to claim 19, characterized in that: The first container is provided with a heating device.

23. The metal powder preparation device according to claim 1, characterized in that: Also includes: A collecting container is communicated with the outlet of the first container.

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