Conductive powder barrel plating device and electroplating method

Abstract

The invention provides a conductive powder barrel plating device and an electroplating method. The conductive powder barrel plating device comprises an electroplating pool (2) used for containing electroplating liquid; the anode (21) is arranged in the electroplating tank (2) and used for being connected with a positive electrode of a power supply; the cathode roller (6) is used for loading conductive powder to be electroplated, and the inner wall of the cathode roller is made of a conductive material; the roller conductive mechanism (5) is connected with the rotating shafts (61 and 62) of the cathode roller (6) and is used for conducting the current of the negative electrode of a power supply to the cathode roller (6); the electric vibration mechanism (3) is connected with the cathode roller (6) and is used for providing vibration with preset amplitude and preset frequency for the cathode roller (6); and the roller rotating mechanism (4) is connected with the cathode roller (6) and is used for driving the cathode roller (6) to rotate around the rotating shafts (61 and 62). According to the invention, the problem of uneven plating caused by agglomeration and poor contact in powder electroplating is fundamentally solved.

Description

Technical Field

[0001] This invention relates to the field of electrochemical deposition technology, and more specifically to a barrel plating apparatus for electroplating conductive powder materials and an electroplating method using the apparatus. Background Technology

[0002] Electroplating is a surface treatment technology that uses the principle of electrolysis to deposit a metal or alloy layer on the surface of a substrate. Traditional electroplating equipment is mainly used for electroplating machined parts (such as fasteners, automotive parts, etc.). These electroplating equipment usually use insulating materials and hollow structures to hold the workpieces, and are not suitable for electroplating conductive powders (such as alloy powders) with fine particles.

[0003] Conductive powders, such as alloy powders (e.g., FeSi, FeNi), have extremely high specific surface areas and are prone to agglomeration in electroplating solutions. Agglomeration leads to the formation of ineffective conductive paths between powder particles and between the powder and the cathode, resulting in extremely uneven current distribution. Consequently, traditional electroplating methods cannot obtain a uniform and dense metal coating on the surface of alloy powders.

[0004] Therefore, there is an urgent need in the field for an electroplating device specifically designed for conductive powders, which can effectively solve problems such as powder agglomeration and uneven conductivity, and achieve high-quality electroplating.

[0005] It should be noted that the information disclosed in the background section above is only for understanding the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the present invention provides a conductive powder barrel plating apparatus and an electroplating method.

[0007] The present invention adopts the following technical solution: In a first aspect, a conductive powder barrel plating apparatus is provided, comprising: an electroplating tank for containing an electroplating solution; an anode disposed within the electroplating tank for connection to a positive terminal of a power supply; a cathode roller for loading conductive powder to be electroplated, the inner wall of which is made of a conductive material; a roller conductive mechanism connected to the rotating shaft of the cathode roller for conducting current from the negative terminal of the power supply to the cathode roller; an electric vibration mechanism connected to the cathode roller for providing vibration of a predetermined amplitude and a predetermined frequency to the cathode roller; and a roller rotation mechanism connected to the cathode roller for driving the cathode roller to rotate around the rotating shaft.

[0008] In a first aspect, a method for electroplating conductive powder is provided, employing the conductive powder barrel plating apparatus described in the first aspect, comprising the following steps: 1) loading the conductive powder to be electroplated into a cathode barrel; 2) activating an electric vibration mechanism to cause the cathode barrel to vibrate at a predetermined frequency, and simultaneously activating a barrel rotation mechanism to cause the cathode barrel to rotate; 3) immersing the cathode barrel into an electroplating bath containing an electroplating solution; 4) connecting a power source to allow current to be conducted through the barrel conductive mechanism to the conductive powder in the cathode barrel for electroplating.

[0009] The beneficial effects of this invention include: By combining an electric vibration mechanism, a drum rotation mechanism, a cathode drum, and a drum conductive mechanism, a synergistic technical solution is constructed. The high-frequency, low-amplitude vibration generated by the electric vibration mechanism effectively disperses the agglomerated conductive powder within the cathode drum, ensuring its full dispersion. The drum rotation mechanism drives the cathode drum to continuously tumble, constantly renewing the contact points between the powder and the drum wall. The conductive inner wall of the drum, acting as the cathode, provides a large effective conductive area for the dispersed powder. The synergistic effect of vibration, rolling, and conductivity ensures that the current can be stably and uniformly transmitted to each powder particle, thereby fundamentally solving the problem of uneven coating caused by agglomeration and poor contact in powder electroplating, achieving the beneficial effect of obtaining a uniform and dense coating on the surface of conductive powder. Attached Figure Description

[0010] Figure 1 This is a three-dimensional schematic diagram of the conductive powder barrel plating apparatus in Embodiment 1 of the present invention.

[0011] Figure 2 This is a three-dimensional schematic diagram of the conductive powder barrel plating device in Embodiment 1 of the present invention from another perspective.

[0012] Figure 3 This is a schematic diagram of the suspended barrel plating module in Embodiment 1 of the present invention.

[0013] Figure 4 This is a schematic diagram of the lifting mechanism in Embodiment 1 of the present invention.

[0014] Figure 5 This is a schematic diagram of the cathode roller in Embodiment 1 of the present invention.

[0015] Figure 6 This is a front view of the cathode roller in Embodiment 1 of the present invention.

[0016] Figure 7 This is a schematic diagram of the electric vibration mechanism in Embodiment 1 of the present invention.

[0017] Figure 8 This is a schematic diagram of the drum rotation mechanism in Embodiment 1 of the present invention.

[0018] Figure 9This is a schematic diagram of the roller conductive mechanism in Embodiment 1 of the present invention.

[0019] Figure 10 This is a partial schematic diagram of another position of the roller conductive mechanism in Embodiment 1 of the present invention.

[0020] Figure 11 This is a scanning electron microscope image of the FeSi alloy powder before electroplating in Example 2 of the present invention.

[0021] Figure 12 This is a scanning electron microscope image of FeSi alloy powder after Cr electroplating in Example 2 of the present invention.

[0022] Figure 13 This is a cross-sectional scanning electron microscope image of the FeSi alloy powder after Cr electroplating in Example 2 of the present invention. Detailed Implementation

[0023] The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of the present invention. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0024] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be used for fixing, coupling, or communication.

[0025] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] This invention provides a conductive powder barrel plating apparatus, comprising: an electroplating tank 2 for containing an electroplating solution; an anode 21 disposed within the electroplating tank 2 for connection to a positive power supply; a cathode roller 6 for loading conductive powder to be electroplated, the inner wall of which is made of a conductive material; a roller conductive mechanism 5 connected to the rotating shafts 61 and 62 of the cathode roller 6 for conducting current from the negative power supply to the cathode roller 6; an electric vibration mechanism 3 connected to the cathode roller 6 for providing vibration of a predetermined amplitude and frequency to the cathode roller 6; and a roller rotation mechanism 4 connected to the cathode roller 6 for driving the cathode roller 6 to rotate around the rotating shafts 61 and 62.

[0028] By leveraging the combined effects of vibration, rolling, and conductivity, the current is stably and uniformly transmitted to every conductive powder particle inside the cathode drum. This fundamentally solves the core technical problem of uneven coating caused by agglomeration and poor contact in powder electroplating, achieving the beneficial effect of obtaining a uniform and dense coating on the surface of conductive powder.

[0029] In some embodiments, the electric vibration mechanism 3, the drum rotation mechanism 4, the drum conductive mechanism 5, and the cathode drum 6 together constitute a suspended barrel plating module; the conductive powder barrel plating device further includes: a lifting mechanism 1, connected to the suspended barrel plating module, used to drive the entire suspended barrel plating module to rise and fall in the vertical direction, so that the cathode drum 6 is immersed in or leaves the electroplating solution in the electroplating tank 2.

[0030] By setting up a lifting mechanism to drive the overall lifting of the suspended barrel plating module, the immersion and removal of the cathode barrel are automated, improving the convenience of operation and production efficiency.

[0031] In some embodiments, the cathode roller 6 includes a graphite roller body 63, an end cap 64, and an insulating sleeve 65; the end cap 64 is porous to allow the electroplating solution to enter the roller body 63; the graphite roller body 63 has a structure that narrows from the middle to both ends, the middle area is used to accommodate the conductive powder to be electroplated, and the areas at both ends are used to prevent the conductive powder to be electroplated from flowing out of the cathode roller 6 when the cathode roller 6 rotates; the insulating sleeve 65 is fitted on the outer wall of the graphite roller body 63, and the insulating sleeve 65 is sealed to the end cap 64.

[0032] The cathode roller is made of graphite and has a narrowing structure, which ensures excellent conductivity and effectively prevents powder from flowing out during rolling. The outer insulating sleeve and sealing structure prevent the electroplating solution from undergoing side reactions on the graphite outer wall, ensuring electroplating efficiency and coating purity.

[0033] In some embodiments, a roller conductive mechanism 5 is connected to each of the rotating shafts 61 and 62 at both ends of the cathode roller 6. The roller conductive mechanism 5 includes: an insulating seat 51; a connecting seat 54 mounted on the insulating seat 51; a bearing seat 510 mounted on the connecting seat 54, on which a bearing 57 for supporting the rotating shafts 61 and 62 is mounted; a conductive component 52 buoyantly disposed on the connecting seat 54; and an elastic clamping member 53 providing clamping force to the conductive component 52, so that the conductive component 52 forms a floating electrical contact with the rotating shafts 61 and 62. In some embodiments, the conductive component 52 includes a conductive shaft 521 and a conductive V-block 522. The elastic clamping member 53 is a compression spring. The roller conductive mechanism 5 also includes a locking screw 55 and a spring stop 59. One end of the spring stop 59 is connected to the connecting seat 54, and the other end is connected to one end of the conductive shaft 521. The brush holder 56 is disposed on the conductive shaft 521 and is gap-connected to the conductive shaft 521. The conductive V-block 522 is fixed to the other end of the conductive shaft 521. The V-groove of the conductive V-block 522 is in line contact with the rotating shafts 61 and 62 of the cathode roller 6 under the action of the elastic clamping member 53. The locking screw 55 is connected to the conductive shaft 521 and is used to connect to the negative terminal of an external power supply.

[0034] The roller conductive mechanism adopts a floating electrical contact design with elastic clamping (such as conductive V-blocks), which can adaptively compensate for minor deviations and vibrations of the rotating shaft, ensuring continuous and stable current conduction under vibration and rotation conditions, and avoiding sparks and power outages.

[0035] In some embodiments, each of the roller conductive mechanisms 5 has two bearings 57, and at least one of the rotating shafts 61 and 62 of the cathode roller 6 has an annular groove 612, which engages with the two bearings 57 to prevent the cathode roller 6 from axially shifting or deviating during rotation.

[0036] In some embodiments, the drum rotation mechanism 4 includes: a motor 41; a first rotating shaft 42 connected to the output end of the motor 41; a second rotating shaft 43 detachably connected to the first rotating shaft 42 via a detachable connector; and a gear 44 disposed on the second rotating shaft 43 for meshing with a corresponding gear 611 disposed on a rotating shaft 61 at one end of the cathode drum 6.

[0037] The rotating drum mechanism features a flip-up quick-release pin design, which makes maintenance and loading / unloading the cathode drum extremely convenient and saves operation time.

[0038] In some embodiments, the connector includes a first quick-release pin 45 and a second quick-release pin 46. When one of the quick-release pins is removed, the second rotating shaft 43 can be rotated away from the cathode roller 6 around the remaining quick-release pin, so as to facilitate the removal and placement of the cathode roller 6.

[0039] In some embodiments, a buffer spring 7 is provided between the lifting mechanism 1 and the electric vibration mechanism 3. The buffer spring between the lifting mechanism and the electric vibration mechanism can effectively buffer vibration, improving equipment stability and lifespan.

[0040] This invention also provides a conductive powder electroplating method using the aforementioned conductive powder barrel plating apparatus, comprising the following steps: 1) Load the conductive powder to be electroplated into the cathode drum 6; 2) Start the electric vibration mechanism 3 to make the cathode roller 6 vibrate with a predetermined amplitude and a predetermined frequency, and at the same time start the roller rotation mechanism 4 to make the cathode roller 6 rotate; 3) Immerse the cathode roller 6 into the electroplating bath 2 containing the electroplating solution; 4) Turn on the power supply so that the current is conducted through the roller conductive mechanism 5 to the conductive powder in the cathode roller 6 for electroplating.

[0041] In some embodiments, in step 2), the vibration frequency of the electric vibration mechanism 3 is in the range of 400-800 Hz and the amplitude is in the range of 0.8-1.2 mm.

[0042] In some embodiments, in step 2), the rotational speed of the cathode roller 6 is greater than 0 and less than or equal to 60 rpm.

[0043] In some embodiments, in step 4), the electroplating current density is 5-15 A / cm². 2 The current density is calculated based on the effective conductive area of ​​the inner wall of the cathode drum 6.

[0044] In some embodiments, in step 3), the electroplating solution is a chromium electroplating solution, wherein the concentration of Cr³⁺ is 2 mol / L-4 mol / L, and the temperature of the electroplating solution is 40℃-80℃.

[0045] In some embodiments, the conductive powder is FeSi or FeNi alloy powder, the particle size of the conductive powder is 5μm to 30μm, and the loading of the conductive powder is 100-400g.

[0046] By optimizing the electroplating process parameters (such as amplitude, vibration frequency, rotation speed, current density, etc.), high-quality and high-efficiency electroplating processes can be achieved for different powder materials and coating requirements.

[0047] The following describes specific embodiments of the present invention.

[0048] Example 1 like Figure 1-10 As shown, a conductive powder barrel plating apparatus includes: Electroplating tank 2 is used to contain electroplating solution; anode 21 is set in the electroplating tank 2 and is used to connect to the positive terminal of the power supply. In this example, anode 21 is a graphite electrode, and a graphite electrode is set on each opposite side of the electroplating tank 2.

[0049] Cathode roller 6, used to load the conductive powder to be electroplated, has an inner wall made of conductive material; see further details. Figure 5 and Figure 6 The cathode roller 6 includes a rotating shaft 61, a rotating shaft 62, a graphite roller body 63, an end cap 64, and an insulating sleeve 65 (in this example, the insulating sleeve is made of polypropylene PP). The rotating shaft 61 has an annular groove 612, which can be used to engage the bearing in the conductive mechanism of the roller. The end cap 64 is porous, allowing the electroplating solution to enter the roller body. The graphite roller body 63 has a structure that narrows from the middle to both ends. The middle area is used to accommodate the conductive powder to be electroplated. The inner wall of the roller body 63 serves as the cathode, conducting electricity to the conductive powder. The areas at both ends are used to prevent the conductive powder to be electroplated from flowing out of the cathode roller 6 with the circulating electroplating solution when the cathode roller 6 rotates. The insulating sleeve 65 is fitted onto the outer wall of the graphite roller body 63. The insulating sleeve 65 and the end cap 64 are sealed together by a corrosion-resistant O-ring 66, which can prevent the outer wall of the roller from undergoing a reduction reaction with the metal ions in the electroplating solution, thus preventing a decrease in the electroplating efficiency of the conductive powder.

[0050] A roller conductive mechanism 5 is connected to each of the two rotating shafts 61 and 62 at both ends of the cathode roller 6. The roller conductive mechanism 5 is used to conduct the current from the negative terminal of the power supply to the cathode roller 6. Specifically, the roller conductive mechanism 5 conducts the current to the rotating shafts 61 and 62, and then through the conductive end caps 64 connected to them, to the conductive inner wall of the cylinder, making the entire inner wall of the cylinder the cathode surface. By introducing the negative terminal of the power supply to both sides of the cathode roller 6, the conductivity of the cathode roller 6 can be made uniform. Further reference... Figure 9 and Figure 10Each of the roller conductive mechanisms 5 includes: an insulating seat 51, mounted on the base plate 32 of the electric vibration mechanism 3; a connecting seat 54, mounted below the insulating seat 51; a bearing seat 510, mounted on the connecting seat 54, on which a bearing 57 for supporting the rotating shafts 61 and 62 is mounted (in this example, the bearing seat 510 is mounted on the lower part of the connecting seat 54, and an inner hole is machined on the bearing seat 510, in which the ceramic bearing 57 is fixedly mounted by a bushing 58); a conductive component 52, buoyantly disposed on the connecting seat 54; and an elastic clamping member 53, providing clamping force to the conductive component 52, so that the conductive component 52 and the rotating shafts 61 and 62 form a floating electrical contact. In this example, the conductive component 52 includes a conductive shaft 521 and a conductive V-block 522. The elastic clamping element 53 is a compression spring. The roller conductive mechanism 5 also includes a locking screw 55 and a spring stop 59. One end of the spring stop 59 is connected to the connecting seat 54, and the other end is connected to one end of the conductive shaft 521. The brush holder 56 is disposed on the conductive shaft 521 and is gapped to the conductive shaft 521 (the gap between the conductive shaft 521 and the brush holder 56 is greater than 0.05mm and can float). The conductive V-block 522 is fixed to... At the other end of the conductive shaft 521, the V-groove of the conductive V-block 522 makes contact with the rotating shafts 61 and 62 of the cathode roller 6 under the action of the elastic clamping member 53; the locking screw 55 is connected to the conductive shaft 521 and is used to connect to the negative terminal of the external power supply. Specifically, during operation, the locking screw 55 is connected to the negative terminal of the rectifier, and conducts electricity to the inner wall of the cathode roller through the conductive shaft 521, the conductive V-block 522, the rotating shaft of the cathode roller, and the end cover of the cathode roller. The conductive V-block 522 and the rotating shaft of the cathode roller are pressed and floated in contact by the compression spring to ensure the stable conductivity of the cathode roller.

[0051] Furthermore, in this example, each of the roller conductive mechanisms 5 has two bearings 57 (ceramic bearings in this example), and at least one of the rotating shafts 61 and 62 of the cathode roller 6 has an annular groove 612 (in this example, an annular groove 612 is provided on the rotating shaft 61), and the annular groove 612 is engaged with the two bearings 57.

[0052] An electric vibration mechanism 3, connected to the cathode roller 6, is used to provide vibration of a predetermined frequency and predetermined amplitude to the cathode roller 6. Specifically, in this example, further reference is made to... Figure 7 The electric vibration mechanism 3 includes a vibrator 31 and a base plate 32. The vibrator 31 is mounted on the base plate 32. At the same time, the base plate 32 can also provide a mounting foundation for the roller rotation mechanism 4 and the roller conductive mechanism 5.

[0053] The drum rotation mechanism 4, connected to the cathode drum 6, drives the cathode drum 6 to rotate around the rotating shafts 61 and 62. (See further details) Figure 8 The drum rotating machine 4 includes: a motor 41; a first rotating shaft 42 connected to the output end of the motor 41 (specifically, the first rotating shaft 42 passes through a bearing and is connected to the motor 41 via a coupling); a second rotating shaft 43 detachably connected to the first rotating shaft 42 via a detachable connector; and a gear 44 disposed on the second rotating shaft 43 for meshing with a corresponding gear 611 disposed on a rotating shaft 61 at one end of the cathode drum 6. In this example, the connecting component includes a first quick-release pin 45 and a second quick-release pin 46. When one of the quick-release pins (such as the second quick-release pin 46) is removed, the second rotating shaft 43 can be rotated away from the cathode roller 6 around the first quick-release pin 45, facilitating the removal and placement of the cathode roller 6. For example, during operation, the motor 51 drives the first rotating shaft 42 and the second rotating shaft 43 to rotate simultaneously. When it is necessary to remove the cathode roller 6 to replace the powder, the second quick-release pin 46 can be removed. With the first quick-release pin 45 as the rotation center, the second rotating shaft 43 can be rotated to the side away from the cathode roller 6, making it easier to remove the cathode roller 6. In this example, the gear 44 is a bevel gear (which may be made of plastic), and correspondingly, the gear 611 on the rotating shaft 61 is also a bevel gear (which may be made of plastic). In this example, the roller rotating machine 4 also includes a motor mounting plate 47. The motor 41 is mounted on the motor mounting plate 47, and the motor mounting plate 47 is mounted on the base plate 32 of the electric vibration mechanism 3.

[0054] The electric vibration mechanism 3, the drum rotation mechanism 4, the drum conductive mechanism 5, and the cathode drum 6 together constitute a suspended barrel plating module (e.g., Figure 3 As shown), the suspended barrel plating module is connected to the lifting mechanism 1. The lifting mechanism 1 is used to drive the entire suspended barrel plating module to move up and down in the vertical direction, so that the cathode roller (6) is immersed in or leaves the electroplating solution in the electroplating tank (2). For details, please refer to further... Figure 4 The lifting mechanism 1 includes a motor 11, a coupling 12, a lifting ring 13, a linear module 14, and a support 15. The support 15 is connected to the electroplating tank, the linear module 14 is connected to the support 15, the coupling 12 is connected to the linear module 14, the motor 11 is fixed on the linear module 14 and connected to the coupling 12, and the lifting ring 13 is connected to the linear module 14 for suspending the barrel plating module. In this example, a hook is provided on the electro-vibration mechanism 3 to suspend the module from the lifting ring 13. A buffer spring 7 is provided between the lifting mechanism 1 and the electro-vibration mechanism 3.

[0055] Example 2 Electroplating a metal layer on the surface of conductive powder using the apparatus of Embodiment 1 described above includes the following steps: 1) Remove the cathode roller 6 by pulling out the second quick-release pin 46. Open the end cap at either end of the cathode roller 6, load the conductive powder to be electroplated into the cathode roller 6, lock the end cap, and attach the cathode roller 6 to the bearing 57. Then, after concentrically positioning the first rotating shaft 42 and the second rotating shaft 43 in the roller rotation mechanism, insert the second quick-release pin 46 while ensuring the two bevel gears are engaged. Suspend the entire suspended roller plating module on the lifting mechanism 1. The conductive powder has a density greater than the electroplating solution and is insoluble in the electroplating solution, with a particle size of 5-30 micrometers. For example, the conductive powder is Fe-based alloy powder (such as FeSi powder, FeNi powder, etc.). In this example, the conductive powder is FeSi alloy powder with an average particle size of 6μm, and the loading amount of FeSi alloy powder is 200g.

[0056] 2) Start the electric vibration mechanism 3 to make the cathode roller 6 vibrate with a predetermined amplitude and frequency, and at the same time start the roller rotation mechanism (4) to make the cathode roller (6) rotate. In this example, the vibration frequency is 700 Hz, the amplitude is 1.2 mm, and the rotation speed of the cathode roller (6) is 30 rpm.

[0057] 3) The lifting mechanism 1 drives the suspended barrel plating module to descend vertically, so that the cathode roller 6 is immersed in the electroplating tank 2 containing the electroplating solution. In this example, the electroplating solution is a chromium electroplating solution. The preparation of the electroplating solution includes: mixing chromic anhydride and pure water, and after complete dissolution, adding trivalent chromium water, hard chromium additive and sulfuric acid in sequence, stirring evenly, and then adding pure water to make up to the target volume. The pH is 5-6, the temperature of the electroplating solution is 60℃, and the Cr³⁺ concentration is 3 mol / L.

[0058] 4) Turn on the power supply and allow the current (in this example, the current density is 8A / cm²) to flow. 2 The conductive powder is conducted to the conductive powder in the cathode drum 6 via the roller conductive mechanism 5 for electroplating for 24 hours (the electroplating time can be adjusted according to the target coating thickness and requirements; in this example, 24 hours is only an example of obtaining a coating of a certain thickness) to electroplat a metal coating on the surface of the conductive powder.

[0059] In this invention, the low-amplitude, high-frequency vibration provided by the electro-vibration mechanism ensures uniform dispersion and prevents agglomeration of the powder. Using a cathode roller increases the cathode conductive area of ​​the powder, improving electroplating efficiency. The powder's own weight causes it to adhere to the inner wall of the cathode roller. During powder circulation, the low-amplitude, high-frequency vibration imparts greater kinetic energy to the powder, and the number of collisions between the cathode roller and the powder at any given moment significantly increases, thereby enhancing the powder's conductivity frequency. After the above electroplating process, a layer of Cr can be deposited on the surface of the FeSi alloy powder, increasing the chromium content from 0 to 0.3 wt%.

[0060] like Figure 11 The image shown is a scanning electron microscope (SEM) image of the FeSi alloy powder before electroplating. Figure 12This is a scanning electron microscope (SEM) image of FeSi alloy powder after Cr electroplating. Figure 13 The image shows a cross-sectional scanning electron microscope (SEM) image of FeSi alloy powder after Cr electroplating, which shows that Cr was successfully electroplated onto the surface of the FeSi alloy powder.

[0061] The above description provides a further detailed explanation of the present invention in conjunction with specific / preferred embodiments, and it should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the scope of protection of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific features, structures, materials, or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. A device for barrel plating of electrically conductive powder, characterized in that The application relates to a conductive powder barrel plating device, which comprises the following components: a barrel plating tank (2) for containing barrel plating liquid; an anode (21) arranged in the barrel plating tank (2) and connected to a positive pole of a power supply; a cathode barrel (6) for loading conductive powder to be barrel plated, wherein the inner wall of the barrel is made of conductive material; a barrel conductive mechanism (5) connected to the rotating shaft (61, 62) of the cathode barrel (6) and used for conducting current from a negative pole of the power supply to the cathode barrel (6); an electric vibration mechanism (3) connected to the cathode barrel (6) and used for providing vibration with a predetermined amplitude and a predetermined frequency to the cathode barrel (6); a barrel rotating mechanism (4) connected to the cathode barrel (6) and used for driving the cathode barrel (6) to rotate around the rotating shaft (61, 62).

2. The electrically conductive powder barrel plating apparatus of claim 1, wherein The electric vibration mechanism (3), the barrel rotating mechanism (4), the barrel conductive mechanism (5) and the cathode barrel (6) jointly form a suspension barrel plating module; the conductive powder barrel plating device further comprises: a lifting mechanism (1) connected to the suspension barrel plating module and used for driving the suspension barrel plating module to vertically ascend or descend as a whole so that the cathode barrel (6) is immersed in or separated from the barrel plating liquid in the barrel plating tank (2).

3. The electrically conductive powder barrel plating apparatus of claim 1, wherein The cathode barrel (6) further comprises a graphite barrel body (63), an end cover (64) and an insulating sleeve (65); the end cover (64) is porous and used for allowing the barrel plating liquid to enter the barrel body (63); the graphite barrel body (63) has a structure that is narrowed from the middle to the two ends, the middle region is used for containing the conductive powder to be barrel plated, the two end regions are used for preventing the conductive powder to be barrel plated from flowing out of the cathode barrel (6) when the cathode barrel (6) rotates, the insulating sleeve (65) is sleeved on the outer wall of the graphite barrel body (63), and the insulating sleeve (65) is in sealing connection with the end cover (64).

4. The electrically conductive powder barrel plating apparatus of claim 1, wherein One barrel conductive mechanism (5) is connected to each of the rotating shafts (61, 62) at the two ends of the cathode barrel (6), and the barrel conductive mechanism (5) comprises: an insulating base (51); a connecting base (54) installed on the insulating base (51); a bearing base (510) installed on the connecting base (54), wherein a bearing (57) for supporting the rotating shaft (61, 62) is installed on the bearing base (510); a conductive assembly (52) arranged on the connecting base (54) in a floating manner; and an elastic pressing part (53) for providing pressing force to the conductive assembly (52) so that the conductive assembly (52) forms floating electric contact with the rotating shaft (61, 62).

5. The electrically conductive powder barrel plating apparatus of claim 4, wherein The conductive assembly (52) comprises a conductive shaft (521) and a conductive V-block (522), the elastic compression member (53) is a compression spring, the drum conductive mechanism (5) further comprises a locking screw (55) and a spring stop lever (59), one end of the spring stop lever (59) is connected to the connecting seat (54), the other end is connected to one end of the conductive shaft (521), the brush seat sleeve (56) is arranged on the conductive shaft (521) and is connected with the conductive shaft (521) in a gap, the conductive V-block (522) is fixed to the other end of the conductive shaft (521), and the V-shaped groove of the conductive V-block (522) is in linear contact with the rotating shaft (61, 62) of the cathode drum (6) under the action of the elastic compression member (53); the locking screw (55) is connected with the conductive shaft (521) and is used for externally connecting the negative pole of a power supply.

6. The electrically conductive powder barrel plating apparatus as claimed in claim 4 or 5, characterized in that, Each of the drum conductive mechanisms (5) has two bearings (57), and at least one of the rotating shafts (61, 62) of the cathode drum (6) has an annular groove (612) which is clamped on the two bearings (57).

7. The electrically conductive powder barrel plating apparatus of claim 1, wherein The drum rotating mechanism (4) comprises: a motor (41); a first rotating shaft (42) connected with the output end of the motor (41); a second rotating shaft (43) detachably connected with the first rotating shaft (42) through a detachable connecting piece; a gear (44) arranged on the second rotating shaft (43) and used for meshing with a corresponding gear (611) arranged on the rotating shaft (61) at one end of the cathode drum (6).

8. The electrically conductive powder barrel plating apparatus of claim 7, wherein The connecting piece comprises a first quick release pin (45) and a second quick release pin (46), when one of the quick release pins is removed, the second rotating shaft (43) can be flipped away from the cathode drum (6) with the remaining quick release pin as the axis, so as to facilitate the taking and placing of the cathode drum (6).

9. The electrically conductive powder barrel plating apparatus of claim 2, wherein A buffer spring (7) is arranged between the lifting mechanism (1) and the electric vibration mechanism (3).

10. A conductive powder electroplating method using the conductive powder barrel plating apparatus according to any one of claims 1 to 9, characterized by, The method comprises the following steps: 1) loading conductive powder to be electroplated into the cathode drum (6); 2) starting the electric vibration mechanism (3) to make the cathode drum (6) vibrate at a predetermined amplitude and a predetermined frequency, and starting the drum rotating mechanism (4) to make the cathode drum (6) rotate; 3) immersing the cathode drum (6) into an electroplating bath (2) containing electroplating solution; 4) connecting a power supply to make current pass through the drum conductive mechanism (5) to the conductive powder in the cathode drum (6) for electroplating.

11. The electroconductive powder electroplating method according to claim 10, wherein In step 2), the vibration frequency of the electric vibration mechanism (3) is in the range of 400-800 Hz, and the amplitude is in the range of 0.8-1.2 mm.

12. The electroconductive powder electroplating method according to claim 10, wherein In step 2), the rotating speed of the cathode drum (6) is greater than 0 and less than or equal to 60 rpm.

13. The electroconductive powder electroplating method according to claim 10, wherein In step 4), the current density for electroplating is 5-15 A / cm 2 .

14. The electroconductive powder electroplating method according to claim 10, wherein In step 3), the electroplating solution is a chromium electroplating solution, the concentration of Cr³⁺ is 2 mol / L-4 mol / L, and the temperature of the electroplating solution is 40℃-80℃.

15. The electroconductive powder electroplating method according to claim 10, wherein The conductive powder is FeSi or FeNi alloy powder, and the particle size of the conductive powder is 5-30 μm.

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