Magnet pickling treatment method and magnet pickling treatment device

Abstract

The application belongs to the technical field of magnet manufacturing, and discloses a magnet pickling treatment method and a magnet pickling treatment device. The magnet pickling treatment method comprises the following steps: installing a magnet base material on a hanger, and installing the hanger above a pickling tank, and immersing the magnet base material in the pickling tank; driving the hanger and / or the pickling tank to move, so that the magnet base material can reciprocate along a first direction and a second direction at an angle relative to the pickling liquid in the pickling tank, and in the reciprocating cycle along the second direction, the time length of the movement towards the liquid surface close to the pickling liquid is less than the time length of the movement away from the liquid surface of the pickling liquid, so that the magnet base material can hit the pickling liquid. Through the magnet pickling treatment method, the problem of dust sticking and the problem of easy gas accumulation can be solved, the pickling amount consistency between batch magnet base materials is high, the pickling amount of each part of a single magnet base material in the circumferential direction is consistent, and the pickling effect of a single magnet base material is good.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnet manufacturing, in particular to a magnet pickling treatment method and a magnet pickling treatment device. BACKGROUND

[0002] NdFeB magnetic material is a product formed by powder metallurgy sintering, which has the characteristics of loose structure, high porosity, poor surface condition and large brittleness. Therefore, the pickling of neodymium iron boron is very difficult. NdFeB permanent magnet material has very high temperature and humidity requirements for storage environment, and the storage time should not be too long, otherwise the outermost layer of neodymium phase is easy to oxidize and hydrogen powder, which leads to poor corrosion resistance, serious rust on the surface of black sheet, and after processing, the surface of black sheet is usually covered with oxide skin, and the edge of black sheet also has burr and burr phenomenon. Nitric acid as a strong oxidizing acid has excellent corrosion effect on the edge and causes great damage to the macroscopic size of the magnet, so it is suitable as a pickling medium for neodymium iron boron material. In the pretreatment process of neodymium iron boron, nitric acid pickling is one of the most critical processes, and the most important purpose is to remove the oxide skin of the product and control the tolerance size of the product. Nitric acid can remove the oxide film on the surface of neodymium iron boron to ensure the adhesion between the coating and the substrate, but the potential difference of each phase of neodymium iron boron is large. If the pickling method is not good, it will cause uneven corrosion of each phase, and finally lead to poor plating quality of the plated product during electroplating after pickling.

[0003] For the pretreatment method of hanging plating products, manual pickling is often used, a small amount of products are put in a flower basket or a net bag, and manual pickling is carried out by manually pulling in the pickling tank. The products collide with each other, causing a certain proportion of missing corners. The size needs to be measured several times during pickling to ensure that the tolerance is qualified, and then loaded into the specified hanger to flow into the electroplating line. Due to the small loading capacity of manual pickling, the pickling efficiency is low, it is difficult to ensure the stability between batches, the pickling consistency is poor, and it is difficult to meet the stability requirements of industrial mass production. For automatic pickling, the existing process often uses compressed air stirring, continuous circulation of filtered pickling solution and other stirring methods in the pickling tank. However, since the parts are clamped on the specified hanger, these two methods cannot thoroughly pickling the contact points of the hanger and the parts, which is not conducive to the plating layer bonding at the subsequent contact position. As a result, there are block-shaped protrusions at this position after electroplating, the adhesion is poor, and the plating layer is easy to peel off at this position.

[0004] Therefore, it is urgent to provide a magnet pickling treatment method with better pickling effect. SUMMARY

[0005] The first object of the present application is to provide a magnet pickling treatment method, which can ensure high consistency of pickling amount between batches of magnet substrates and good pickling effect of individual magnet substrates.

[0006] The second object of the present application is to provide a magnet pickling treatment device, which is used for pickling treatment of magnets, can improve the automatic pickling consistency of batch magnet substrates, and is especially suitable for magnet substrates with a single weight of 36g-320g.

[0007] To achieve the above object, the present application adopts the following technical solutions:

[0008] The present application discloses a magnet pickling treatment method, which comprises the following steps: installing a magnet substrate on a hanger, and installing the hanger above a pickling tank and immersing the magnet substrate in the pickling tank; driving the hanger and / or the pickling tank to move, so that the magnet substrate can reciprocate in a first direction and a second direction at an angle relative to the pickling liquid in the pickling tank, and the first direction is parallel to the liquid surface of the pickling liquid; wherein: in the reciprocating cycle along the second direction, the movement time length towards the liquid surface of the pickling liquid is less than the movement time length away from the liquid surface of the pickling liquid, so that the magnet substrate can hit the pickling liquid; the movement amplitude of the magnet substrate relative to the pickling liquid along the second direction is L, the size of the magnet substrate along the second direction is H, and L and H satisfy the relationship: L / H=0.03-0.4.

[0009] In some embodiments, the movement frequency of the magnet substrate relative to the pickling liquid along the second direction is 50 times / minute-150 times / minute.

[0010] In some embodiments, the initial acceleration of the magnet substrate relative to the pickling liquid along the second direction is 480cm / s 2 -500cm / s 2 .

[0011] In some embodiments, the movement frequency of the magnet substrate relative to the pickling liquid along the first direction is 10 times / minute-30 times / minute.

[0012] In some embodiments, the initial acceleration of the magnet substrate relative to the pickling liquid along the first direction is 2.35cm / s 2 -28cm / s 2 .

[0013] In some embodiments, the pickling time of the magnet substrate is 180 seconds-600 seconds; and / or: the pickling temperature of the magnet substrate is 20℃-40℃.

[0014] In some embodiments, the concentration of nitric acid in the pickling liquid of the magnet substrate is 2%-3%; and / or: the weight of the magnet substrate is 36g-320g.

[0015] The application further discloses a magnet pickling treatment device used for performing the magnet pickling treatment method; the magnet pickling treatment device comprises a pickling tank used for containing a pickling solution, a hanger provided with a plurality of hanging parts, each of the hanging parts being used for hanging at least one magnet substrate, and a driving mechanism used for driving the pickling tank and / or the hanger to move; wherein: the driving mechanism drives the hanger and / or the pickling tank to move, so that the magnet substrate can reciprocate along a first direction and a second direction which are at an angle relative to the pickling solution in the pickling tank, and the first direction is parallel to the liquid surface of the pickling solution; wherein: in a reciprocating cycle along the second direction, the time length of the movement towards the liquid surface of the pickling solution is less than the time length of the movement away from the liquid surface of the pickling solution, so that the magnet substrate can hit the pickling solution; the movement amplitude of the magnet substrate relative to the pickling solution along the second direction is L, the size of the magnet substrate along the second direction is H, and L and H satisfy the relationship L / H = 0.03-0.4.

[0016] In some embodiments, the driving mechanism comprises a hitting module and a swinging module, the hitting module is connected with the hanger and is used for driving the hanger to move along the second direction, and the swinging module is connected with the pickling tank and is used for driving the pickling tank to move along the first direction.

[0017] In some embodiments, the magnet pickling treatment device further comprises a support frame, a support seat and a flying bar, the support frame is used for supporting the pickling tank, and the flying bar is used for supporting the hanger; the support seat is used for supporting the flying bar, and the driving mechanism comprises a first driving module and a second driving module; wherein: the first driving module is connected with the support frame and is used for driving the support frame to reciprocate along the first direction; and the second driving module is installed on the support frame and is used for driving the support seat to reciprocate along the first direction.

[0018] The method disclosed by the application can make the batch magnet substrates hung on the hanger not be affected by the hanging point positions of the hanger during the pickling process, so that the pickling amounts of the magnet substrates at different positions are consistent, and the pickling amounts of the batch magnet substrates are consistent.

[0019] Additional aspects and advantages of the application will be better understood from the following descriptions. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a flowchart of the magnet pickling treatment method of the embodiment of the application;

[0021] Figure 2is a structural diagram of a magnet pickling treatment device according to an embodiment of the present application.

[0022] Figure 3 is a structural diagram of a magnet pickling treatment device according to another embodiment of the present application.

[0023] Reference Signs:

[0024] 100, pickling tank; 200, hanger; 300, driving mechanism; 310, beating module; 320, swinging module; 330, first driving module; 340, second driving module;

[0025] 400, support frame; 500, support seat; 600, flying bar. DETAILED DESCRIPTION

[0026] The present application will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are intended to be merely illustrative of the present application and not in limitation thereof. It should also be noted that, for the purpose of description, only the parts related to the present application are shown in the drawings and not all the parts.

[0027] In the description of the present application, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrated; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] In the present application, unless otherwise explicitly specified and limited, the "upper" or "lower" of the first feature to the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "upper", "above" and "on" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "below", "under" and "under" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0029] In the description of the present embodiment, the terms "upper", "lower", "right", "left", and the like, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used to distinguish in the description, and have no special meaning.

[0030] The present application discloses a magnet pickling treatment method, referring to Figure 1 The flow of the magnet pickling treatment method is as follows:

[0031] S1: install the magnet substrate on the hanger 200, and install the hanger 200 above the pickling tank 100, and immerse the magnet substrate in the pickling tank 100; it should be noted that the hanger 200 can be hook-shaped, or U-shaped or V-shaped structure with bottom and side support, the specific structure of the hanger 200 can be selected according to the specific shape of the magnet substrate and the pickling requirements, and the specific structure of the hanger 200 is not limited here.

[0032] S2: drive the hanger 200 and / or the pickling tank 100 to move, so that the magnet substrate can reciprocate along the first direction and the second direction at an angle relative to the pickling liquid in the pickling tank 100, the first direction is parallel to the liquid surface of the pickling liquid; in the period of reciprocating along the second direction, the time length of the movement towards the liquid surface of the pickling liquid is less than the time length of the movement away from the liquid surface of the pickling liquid, so that the magnet substrate can "hit" the pickling liquid. It should be noted that in step S2, the hanger 200 can be driven to reciprocate along the first direction and the second direction by one driving mechanism 300, the pickling tank 100 can be driven to move along the first direction and the second direction by one driving mechanism 300, or the pickling tank 100 and the hanger 200 can be driven respectively by two driving mechanisms 300, one of which reciprocates along the first direction, and the other reciprocates along the second direction. The specific movement form of the hanger 200 and the pickling tank 100 can be adjusted according to actual needs.

[0033] The inventors of the present disclosure found that when the magnet substrate is placed on the hanger 200, the magnet substrate is prone to insufficient pickling and insufficient pickling amount at the hanging point position where the magnet substrate contacts the hanger 200. In the prior art, the pickling degree of the magnet substrate at the hanging point is improved by switching the hanging point, which requires multiple hangers 200 or corresponding motion mechanisms to realize the switching of the hanging point between two positions. On the one hand, this relatively fixed multiple hanging points still have the problems of insufficient pickling and insufficient pickling amount, and on the other hand, the increase of mechanisms in the system reduces the stability of the mechanical system. With the long-time operation of the mechanical system, the stability of the magnet substrate pickling is difficult to guarantee. The present disclosure proposes a technical idea of moving the magnet substrate along its center circumference during pickling without adding redundant hangers 200 or motion mechanisms. The hanging point position where the magnet substrate contacts the hanger 200 is continuously changed during pickling, so that the magnet substrate is a hanging point at any position during pickling. In another aspect, the hanging point of the magnet substrate disappears during pickling, thereby solving the problem of insufficient pickling at the hanging point while ensuring the stability of the entire pickling system.

[0034] In addition, under the above technical idea, the inventors of the present disclosure found that when nitric acid is used to pickle neodymium iron boron magnets, reaction products such as nitrate and nitrogen oxides, and neodymium-rich phase particles dissolved and detached from the magnets will continuously adsorb on the surface of the substrate, forming a "hanging ash layer". If the hanging ash layer is not removed in time, it will affect the continuous pickling process of the magnet substrate, and also increase the amount of ash removal and the removal time of the subsequent ultrasonic cleaning. At the same time, after nitric acid pickling, small corrosion cavities will be formed on the surface of the neodymium iron boron substrate. Compared with the smooth area, these holes are more prone to store the generated gas, which is more likely to accumulate and stay in this place. Since it cannot escape in time, it hinders the further release of hydrogen ions inside the magnet substrate. It can be understood that during actual pickling, the magnet substrate can reciprocate in the first direction and the second direction at an angle relative to the pickling liquid in the pickling tank 100. The first direction is parallel to the liquid surface of the pickling liquid. By moving the magnet substrate relative to the pickling liquid in the direction parallel to the liquid surface, the gas can be carried away during pickling, so that the gas at the hanging point (the contact point between the magnet substrate and the hanger 200) is separated from the magnet substrate. During the reciprocating movement in the second direction, the magnet substrate can hit the pickling liquid, which not only instantaneously separates the magnet substrate with a large single weight from the hanger 200, but also partially peels off the reaction products such as nitrate adsorbed on the surface of the magnet substrate from the magnet substrate during separation, thereby improving the ash hanging phenomenon. In addition, since the magnet substrate can reciprocate in the first direction and the second direction at an angle relative to the pickling liquid in the pickling tank 100, the consistency of the pickling amount between batches of magnet substrates can be ensured, the pickling amount at each position of a single magnet substrate in the circumferential direction is consistent, and the pickling effect of a single magnet substrate is good.

[0035] Optionally, the first direction is a horizontal direction, and the second direction is a vertical direction. Thus, in the actual pickling process, by controlling the parameters of the first direction and the second direction, the magnet substrate can be rotated in the circumferential direction in the pickling solution, thereby further ensuring the consistency of the pickling amount between the batch magnet substrates, the consistency of the pickling amount at different positions of the circumferential direction of the single magnet substrate, and the pickling effect of the single magnet substrate. Of course, in other embodiments of the present application, the first direction and the second direction can be selected according to actual needs, and the first direction and the second direction can also be arranged non-perpendicularly.

[0036] Optionally, the movement amplitude of the magnet substrate relative to the pickling solution along the second direction is L, and the size of the magnet substrate along the second direction is H, and L and H satisfy the relationship: L / H = 0.03-0.4. As can be understood from the foregoing, during the movement of the magnet substrate relative to the pickling solution along the second direction, the magnet substrate can hit the pickling solution, not only can the single magnet substrate with large weight be separated from the hanger 200 instantaneously, if the movement amplitude of the magnet substrate relative to the pickling solution along the second direction is too large, the magnet substrate will fall during the throwing process, and if the amplitude is too small, the separation and rotation effect described above cannot be achieved. In the present embodiment, by controlling the ratio of the size of the magnet substrate along the second direction and the movement amplitude of the magnet substrate relative to the pickling solution along the second direction, the amplitude of the magnet substrate relative to the pickling solution along the second direction is controlled, thereby ensuring the consistency of the pickling of the magnet substrate and the pickling effect. Of course, in other embodiments of the present application, the ratio of the movement amplitude of the magnet substrate relative to the pickling solution along the second direction and the size of the magnet substrate along the second direction can also be selected according to actual needs, and the amplitude of the magnet substrate along the second direction can also be controlled by controlling the movement parameters of the magnet substrate along the second direction. Optionally, L / H can be 0.03, 0.05, 0.1, 0.15, 0.18, 0.2, 0.23, 0.25, 0.27, 0.3, 0.32, 0.35, 0.37, 0.4, and preferably L / H is 0.03-0.25. In the above preferred manner, a more sufficient and complete separation and rotation effect can be achieved.

[0037] Optionally, the frequency of the movement of the magnet substrate relative to the acid pickling solution in the second direction is 50-150 times per minute. In the frequency of the movement, "times" refers to one reciprocating motion. Specifically, the frequency of the movement of the magnet substrate relative to the acid pickling solution in the second direction can be 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150 times per minute. Of course, the frequency of the movement can also be other values within the range of 50-150 times per minute, and is not limited to the above examples. It can be understood that the frequency of the movement of the magnet substrate relative to the acid pickling solution in the second direction is too fast or too slow, which is not conducive to the instantaneous separation of the magnet substrate with a large single weight from the hanger 200. Controlling the frequency of the movement of the magnet substrate relative to the acid pickling solution in the second direction to 50-150 times per minute is conducive to ensuring the instantaneous separation of the magnet substrate with a large single weight from the hanger 200, thereby improving the phenomenon of hanging dust.

[0038] Optionally, the initial acceleration of the magnet substrate relative to the acid pickling solution in the second direction is 480-500 cm / s 2 . 2 Specifically, the initial acceleration of the magnet substrate relative to the acid pickling solution in the second direction can be 480, 481, 482, 483, 484, 485, 486, 487, 488, 489, 490, 491, 492, 493, 494, 495, 496, 497, 498, 499, 500 cm / s 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 ​​​​​​​​​​​​​​​​​​​​of course the initial acceleration can also be 480cm / s 2 -500cm / s 2 other values within the range of 10-30 times / minute, and is not limited to the above examples. It can be understood that if the initial acceleration of the magnet substrate relative to the pickling solution in the second direction is too fast or too slow, the magnet substrate with a large single weight will be separated from the hanger 200 instantaneously, and the initial acceleration of the magnet substrate relative to the pickling solution in the second direction is 480cm / s 2 -500cm / s 2 , which is conducive to ensuring that the magnet substrate with a large single weight is separated from the hanger 200 instantaneously, thereby facilitating the improvement of the ashing phenomenon.

[0039] Optionally, the movement frequency of the magnet substrate relative to the pickling solution in the first direction is 10-30 times / minute. Specifically, the movement frequency of the magnet substrate relative to the pickling solution in the first direction can be 10 times / minute, 11 times / minute, 12 times / minute, 13 times / minute, 14 times / minute, 15 times / minute, 16 times / minute, 17 times / minute, 18 times / minute, 19 times / minute, 20 times / minute, 21 times / minute, 22 times / minute, 23 times / minute, 24 times / minute, 25 times / minute, 26 times / minute, 27 times / minute, 28 times / minute, 29 times / minute, 30 times / minute. Of course, the movement frequency can also be other values within the range of 10-30 times / minute, and is not limited to the above examples. It can be understood that if the movement frequency of the magnet substrate relative to the pickling solution in the first direction is too fast or too slow, it is not conducive to improving the pickling effect and pickling consistency. Controlling the movement frequency of the magnet substrate relative to the pickling solution in the first direction to 10-30 times / minute is conducive to ensuring the pickling effect and improving the pickling consistency.

[0040] Optionally, the initial acceleration of the magnet substrate relative to the pickling solution in the first direction is 2.35cm / s 2 -28cm / s 2 : Specifically, the initial acceleration of the magnet substrate relative to the pickling solution in the first direction can be 2.35cm / s 2 , 3cm / s 2 , 4cm / s 2 , 5cm / s 2 , 6cm / s 2 , 7cm / s 2 , 8cm / s 2 , 9cm / s 2 , 10cm / s 2 , 11cm / s 2 , 12cm / s 2 , 13cm / s 2 , 14cm / s 2 , 15cm / s2 , 16 cm / s 2 , 17 cm / s 2 , 18 cm / s 2 , 19 cm / s 2 , 20 cm / s 2 , 21 cm / s 2 , 22 cm / s 2 , 23 cm / s 2 , 24 cm / s 2 , 25 cm / s 2 , 26 cm / s 2 , 27 cm / s 2 , 28 cm / s 2 . Of course, the initial acceleration can also be 2.35 cm / s 2 - 28 cm / s 2 . Other values within the range are not limited to the above examples. It can be understood that the initial acceleration of the magnet substrate relative to the acid pickling solution in the first direction is too fast or too slow, which is not conducive to improving the pickling effect and the pickling consistency. The initial acceleration of the magnet substrate relative to the acid pickling solution in the first direction is 2.35 cm / s 2 - 28 cm / s 2 , which is conducive to ensuring the pickling effect and improving the pickling consistency.

[0041] Optionally, the pickling time of the magnet substrate is 180 seconds-600 seconds, and the pickling time of the magnet substrate is too long or too short, which is not conducive to ensuring the pickling effect. The pickling time of the magnet substrate is controlled within the range of 300 seconds-600 seconds, which can improve the pickling effect. Of course, in other embodiments of the present application, the pickling time of the magnet substrate can be selected according to actual needs, and is not limited to the above limitations.

[0042] Optionally, the pickling temperature of the magnet substrate is 20℃-40℃, and the pickling temperature of the magnet substrate is too high or too low, which is not conducive to ensuring the pickling effect. The pickling temperature of the magnet substrate is controlled within the range of 20℃-40℃, which can improve the pickling effect. Of course, in other embodiments of the present application, the pickling temperature of the magnet substrate can be selected according to actual needs, and is not limited to the above limitations.

[0043] Optionally, the concentration of nitric acid in the pickling solution of the magnet substrate is 2%-3%; the concentration of nitric acid in the pickling solution is too large or too small, which is not conducive to ensuring the pickling effect. The concentration of nitric acid is controlled within the range of 2%-3%, which can improve the pickling effect. Of course, in other embodiments of the present application, the concentration of nitric acid in the pickling solution can be selected according to actual needs, and is not limited to the above limitations.

[0044] Optionally, the weight of the magnet substrate is 36g-320g. Of course, in other embodiments of the present application, the magnet substrate can be selected according to the specific product needs, and is not limited to the above range.

[0045] Preferably, the shape of the magnet substrate can be annular, cylindrical, elliptical cylindrical, or containing a partial arc shape.

[0046] Optionally, the composition of the magnet substrate is R-T-B-M, specifically: R represents rare earth elements, and the mass percentage is 28wt%-31.5wt%; R is selected from at least one of Nd and (Pr, La, Ce, Dy, Tb, Ho); the mass percentage of B is 0.85wt%-1.05wt% or less; the mass percentage of M is less than 3wt%, and is selected from one or more of Cu, Zn, Ga, Zr, Ti, Nb, Al, Ag, W, T is selected from Fe and / or Co and other impurity elements, wherein Fe accounts for more than 97wt% of the total amount of T, and the mass percentage of T is the balance in addition to R, B and M.

[0047] The present application also discloses a magnet pickling treatment device, referring to Figure 2 and Figure 3 The magnet pickling treatment device is used to perform the magnet pickling treatment method described above. The magnet pickling treatment device comprises a pickling tank 100 and a hanger 200, the pickling tank 100 is used to hold pickling liquid, the hanger 200 has a plurality of hanging parts, each hanging part is used to hang at least one magnet substrate, and a driving mechanism 300 drives the pickling tank 100 and / or the hanger 200 to move. The driving mechanism 300 drives the hanger 200 and / or the pickling tank 100 to move, so that the magnet substrate can reciprocate along a first direction and a second direction which form an angle with respect to the pickling liquid in the pickling tank 100, the first direction is parallel to the liquid surface of the pickling liquid; in the period of reciprocating along the second direction, the time length of moving towards the liquid surface of the pickling liquid is less than the time length of moving away from the liquid surface of the pickling liquid, so that the magnet substrate can "hit" the pickling liquid.

[0048] In the actual pickling process, the driving mechanism 300 can drive the pickling tank 100 and / or the hanger 200 to move, so that the magnet base material hung on the hanger 200 reciprocates along the first direction and the second direction at an angle relative to the pickling solution in the pickling tank 100. By reciprocating the magnet base material along the first direction relative to the pickling solution, the gas in the magnet base material can be carried away during the pickling process, so that the gas at the contact point of the magnet base material and the hanger 200 is separated from the magnet base material. By reciprocating the magnet base material along the second direction relative to the pickling solution, the magnet base material hits the pickling solution, which not only separates the magnet base material from the hanger 200 instantaneously, but also peels off the reaction products such as nitrate adsorbed on the surface of the magnet base material, thereby improving the phenomenon of dusting. In addition, the two-way movement of the magnet base material relative to the pickling solution in the pickling tank 100 can also ensure that the pickling amount of the batch magnet base material is consistent, the pickling amount of each part of the single magnet base material is consistent, and the pickling effect of the single magnet base material is good.

[0049] In one specific embodiment, referring to Figure 2 The driving mechanism 300 includes a hitting module 310 and a swinging module 320. The hitting module 310 is connected to the hanger 200 and is used to drive the hanger 200 to move along the second direction. The swinging module 320 is connected to the pickling tank 100 and is used to drive the pickling tank 100 to move along the first direction. It should be noted that the driving mechanism 300 is divided into the hitting module 310 and the swinging module 320, which is beneficial to control the movement parameters of the hanger 200 and the pickling tank 100, and simplifies the structure of the entire magnet pickling processing device and reduces the manufacturing cost of the magnet pickling processing device. In the embodiment of the application, the hitting module 310 can be a structure of a motor-driven eccentric wheel, a cylinder push rod, or a motor-driven four-bar mechanism, and the specific type of the hitting module 310 can be selected according to actual needs, as long as the hanger 200 can move along the second direction, and the movement time of the magnet base material towards the liquid surface of the pickling solution is less than the movement time of the magnet base material away from the liquid surface of the pickling solution in the reciprocating movement cycle along the second direction, so that the magnet base material can hit the pickling solution. The swinging module 320 can be a structure of a motor-driven eccentric wheel, a cylinder push rod, a motor-driven ball screw structure, or a motor-driven gear rack movement, as long as the pickling tank 100 can stably reciprocate along the first direction. Of course, in an alternative embodiment, the hitting module 310 can be connected to the pickling tank 100 and used to drive the pickling tank 100 to move along the second direction, and the swinging module 320 can be connected to the hanger 200 and used to drive the hanger 200 to move along the first direction, as long as the movement forms described above can be ensured.

[0050] In another specific embodiment, referring toFigure 3 As shown, the magnet pickling device further comprises a support frame 400 for supporting the pickling tank 100, a flying bar 600 for supporting the hanger 200, and a support base 500 for supporting the flying bar 600; the driving mechanism 300 comprises a first driving module 330 and a second driving module 340. The first driving module 330 is connected with the support frame 400 and is used to drive the support frame 400 to reciprocate along a first direction; the second driving module 340 is installed on the support frame 400 and is used to drive the support base 500 to reciprocate along a second direction. It can be understood that after the hanger 200 is installed on the flying bar 600 and a plurality of magnet substrates are hung on the hanger 200, in the pickling process, the second driving module 340 can drive the support base 500 to move along the second direction, and since the flying bar 600 is installed on the support base 500, in the process of the support base 500 moving along the second direction, the flying bar 600 can drive the hanger 200 to reciprocate along the second direction, and the first driving module 330 can drive the support frame 400 to move along the first direction, and the support frame 400 serves as a support member of the support base 500, the flying bar 600 and the second driving module 340, and when the support frame 400 moves along the first direction, the hanger 200 can move along the first direction, thereby realizing the movement of the hanger 200 along the first direction and the second direction relative to the pickling tank 100.

[0051] It should be noted that in the embodiments of the present application, the first driving module 330 and the second driving module 340 can be a structure of a motor driving eccentric wheel, can be a cylinder push rod, can be a motor driving ball screw structure, and can be a motor driving gear rack movement, as long as it is a linear reciprocating driving structure capable of driving the support base 500 and the support frame 400 to move, and the specific type of the first driving module 330 and the second driving module 340 is not limited herein.

[0052] In the description of the present specification, the description of the terms "some embodiments", "other embodiments", and the like means that the specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0053] Obviously, the above embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the embodiments of the present application. Those skilled in the art can make various obvious changes, readjustments and substitutions without departing from the scope of the present application. It is unnecessary and impossible to enumerate all the embodiments. Any modification, equivalent substitution and improvement within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

[0054] The present disclosure is further illustrated by the following examples, but the present disclosure is not limited in any way by the following examples. The neodymium-iron-boron magnet substrate in the following examples and comparative examples has a composition represented by (PrNd)29.5Co0.7B0.91Cu0.1Ga0.1Zr0.2Fe68.49, and is prepared by the following method: raw materials are melted according to the formulation, and an alloy rapid solidification sheet having a thickness of 0.3 mm is obtained by a conventional rapid solidification method; then hydrogen breaking is performed, followed by gas milling to obtain a powder having an average particle size of 4.2 μm, the gas composition including air, a carbon-containing solvent, a lubricant and an antioxidant commonly used in the art; then the powder is subjected to orientation molding in a magnetic field of 2 T, and after static pressing, sintering is performed at a sintering temperature of 1000 °C for a sintering time of 8 h; after cooling to 900 °C, primary aging is performed for 3 h, and then secondary aging is performed at 500 °C for 5 h to obtain a magnetic blank; after the magnetic blank is cut, a magnet substrate having a size of Φ50 mm*5 mm is obtained, and the magnet substrate has a single weight of 73.3 g.

[0055] Example 1

[0056] Example 1 provides a method for preparing a neodymium-iron-boron magnet, the method comprising the following steps:

[0057] The magnet substrate is installed on the hanger 200, the magnet substrate has a size H = 50 mm in the second direction, and the hanger 200 is installed above the pickling tank 100 and immersed in the pickling solution in the pickling tank 100; the hanger 200 and the pickling tank 100 are driven to move so that the magnet substrate can reciprocate along the first direction and the second direction at an angle with respect to the pickling solution in the pickling tank 100, the first direction is parallel to the liquid level of the pickling solution, and the second direction is at an angle of 90° with respect to the liquid level of the pickling solution. In the cycle of reciprocating movement in the second direction, the movement frequency in the second direction is 80 times per minute, the initial acceleration in the second direction is 480 cm / s 2 In the cycle of reciprocating movement in the first direction, the movement frequency in the first direction is 30 times per minute, and the initial acceleration in the first direction is 20 cm / s 2, the ratio of the movement amplitude of the acid pickling liquid along the second direction to the dimension along the second direction is 0.18, i.e. the movement amplitude L along the second direction is 9 mm, the acid pickling temperature of the acid pickling liquid is 25°C, and the acid pickling duration is 300 seconds. The hanger 200 carrying the magnet substrate is installed above the water tank to obtain the neodymium-iron-boron magnet after ultrasonic water washing.

[0058] Example 2

[0059] The neodymium-iron-boron magnet is prepared by the same method as in Example 1, except that the angle between the second direction and the liquid surface of the acid pickling liquid is 60°, the movement frequency along the second direction in the cycle of reciprocating movement along the second direction is 100 times per minute, the initial acceleration along the second direction is 483 cm / s 2 .

[0060] Example 3

[0061] The neodymium-iron-boron magnet is prepared by the same method as in Example 1, except that the movement frequency along the first direction in the cycle of reciprocating movement along the first direction is 10 times per minute, and the initial acceleration along the first direction is 2.45 cm / s 2 .

[0062] Comparative Example 1

[0063] The neodymium-iron-boron magnet is prepared by the same method as in Example 1, except that there is no reciprocating movement along the second direction, i.e. the movement frequency along the second direction is 0.

[0064] Comparative Example 2

[0065] The neodymium-iron-boron magnet is prepared by the same method as in Example 1, except that the ratio of the movement amplitude of the acid pickling liquid along the second direction to the dimension along the second direction is 2.

[0066] Comparative Example 3

[0067] The neodymium-iron-boron magnet is prepared by the same method as in Example 1, except that the initial acceleration along the second direction is 50 cm / s 2 , and the initial acceleration along the first direction is 50 cm / s 2 .

[0068] Test Example

[0069] The neodymium-iron-boron magnets prepared in Examples 1-3 and Comparative Examples 1-3 are tested for the circumferential dimension of the magnet, the amount of dust removal, and the average value of the acid pickling amount by the following method, and the test results are shown in Table 1.

[0070] (1) Circumferential dimension of the magnet: the thickness of the neodymium-iron-boron magnet at two arbitrary positions on the circumference is measured by using a micrometer and the data is recorded;

[0071] (2) The amount of dust removal: after the magnet substrate passes through the nitric acid pickling tank, the magnet substrate is placed in the ultrasonic cleaning tank and washed for 10s, then the magnet substrate is taken out for appearance test of the surface dust degree, and the brightness of the dust layer is observed.

[0072] (3) The average value of pickling amount: the micrometer is used to test the pickling amount of two batches of neodymium iron boron magnets, 20 pieces of neodymium iron boron magnets are taken from each batch, and the average value of the pickling amount of the neodymium iron boron magnets between the two batches is calculated.

[0073] Table 1

[0074]

[0075] From the circumferential size data of examples 1-3 and comparative examples 1-3, it can be seen that the thickness difference of the magnet at any two positions of the circumference is small, the pickling amount at each position of the magnet is consistent, and the automatic pickling effect is good. From the dust removal amount data, it can be seen that the magnet prepared by the method of the present disclosure has good dust removal effect, which can significantly improve the dusting phenomenon in the pickling process, and a large amount of dust can be removed after a short time of ultrasonic, and the appearance is bright white. From the average value of the pickling amount, it can be seen that the pickling amount of the magnet prepared by the method of the present disclosure is close between different batches, which indicates that the pickling amount control consistency of the batch product is good. It is particularly pointed out that, comparative example 2 is not within the range of the present disclosure because L / H, a large amount of magnet substrate falls from the hanger during pickling, resulting in a low yield of the final batch pickling product, so there is no corresponding data.

[0076] The above examples illustrate the detailed features of the present application, but the present application is not limited to the above detailed features, i.e. it does not mean that the present application must rely on the above detailed features to be implemented. Those skilled in the art should understand that any improvement of the present application, equivalent replacement of the technical features selected by the present application, addition of auxiliary technical features, selection of specific modes, etc. fall within the protection scope and disclosure scope of the present application.

Claims

1. A method of pickling a magnet, characterized by, The magnet substrate is installed on a hanger (200), and the hanger (200) is installed above a pickling tank (100), and the magnet substrate is immersed in the pickling tank (100); The hanger (200) and / or the pickling tank (100) are driven to move, so that the magnet substrate can reciprocate along a first direction and a second direction at an angle relative to the pickling solution in the pickling tank (100), the first direction being parallel to the liquid level of the pickling solution; wherein: In the cycle of reciprocating movement along the second direction, the time length of movement towards the liquid level of the pickling solution is less than the time length of movement away from the liquid level of the pickling solution, so that the magnet substrate can hit the pickling solution; The movement amplitude of the magnet substrate relative to the pickling solution along the second direction is L, and the size of the magnet substrate along the second direction is H, L and H satisfy the relationship: L / H=0.03-0.4; wherein: The movement frequency of the magnet substrate relative to the pickling solution along the second direction is 50 times / minute-150 times / minute; The movement frequency of the magnet substrate relative to the pickling solution along the first direction is 10 times / minute-30 times / minute; The initial acceleration of the magnet substrate relative to the pickling solution in the second direction is 480 cm / s 2 - 500 cm / s 2 ; The definition of "times" in the movement frequency refers to the action of completing one reciprocating movement. The initial acceleration of the magnet substrate relative to the pickling solution in the first direction is 2.35 cm / s 2 - 28 cm / s 2 ; The pickling time of the magnet substrate is 180 seconds-600 seconds; and / or:

2. The magnet pickling treatment method according to claim 1, characterized by The pickling temperature of the magnet substrate is 20℃-40℃. The concentration of nitric acid in the pickling solution of the magnet substrate is 2%-3%; and / or:

3. The magnet pickling treatment method according to claim 1, characterized by The weight of the magnet substrate is 36g-320g. The magnet pickling treatment device is used to perform the magnet pickling treatment method according to any one of claims 1-3; 4. A magnet pickling treatment apparatus characterized by comprising: The magnet pickling treatment device comprises: A pickling tank (100) for containing a pickling solution; A hanger (200) having a plurality of hanging parts, each of which is used to hang at least one magnet substrate; A driving mechanism (300) for driving the pickling tank (100) and / or the hanger (200) to move; wherein: The driving mechanism (300) drives the hanger (200) and / or the pickling tank (100) to move, so that the magnet substrate can reciprocate along a first direction and a second direction at an angle relative to the pickling solution in the pickling tank (100), the first direction being parallel to the liquid level of the pickling solution; wherein: In the cycle of reciprocating movement along the second direction, the time length of movement towards the liquid level of the pickling solution is less than the time length of movement away from the liquid level of the pickling solution, so that the magnet substrate can hit the pickling solution; The movement amplitude of the magnet substrate relative to the pickling solution along the second direction is L, and the size of the magnet substrate along the second direction is H, L and H satisfy the relationship: L / H=0.03-0.

4. ​ 5. The magnet pickling treatment apparatus according to claim 4, characterized by The driving mechanism (300) comprises a beating module (310) and a swinging module (320), the beating module (310) is used for being connected with the hanger (200) and driving the hanger (200) to move along the second direction, and the swinging module (320) is connected with the pickling tank (100) and is used for driving the pickling tank (100) to move along the first direction.

6. The magnet pickling treatment apparatus according to claim 4, characterized by The magnet pickling treatment device further comprises a support frame (400), a support seat (500) and a flying bar (600), the support frame (400) is used for supporting the pickling tank (100), the flying bar (600) is used for supporting the hanger (200), and the support seat (500) is used for supporting the flying bar (600); the driving mechanism (300) comprises a first driving module (330) and a second driving module (340); wherein ； The first driving module (330) is connected with the support frame (400) and is used for driving the support frame (400) to reciprocate along the first direction; The second driving module (340) is installed on the support frame (400) and is used for driving the support seat (500) to reciprocate along the second direction.

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