Tantalum alloy drawing die and tantalum alloy sticking die production method

Abstract

The present invention provides a tantalum alloy drawing die and a tantalum alloy sticking die production method, which are used for drawing tantalum alloy, and include an upper insert, a fixed retaining ring and a positioning push rod, wherein the upper insert includes a first surface and a second surface opposite to each other, and the upper insert is provided with a cavity, and the cavity passes through the first surface and the second surface, and the fixed retaining ring is arranged on the first surface, and the fixed retaining ring is provided with a receiving groove, and the receiving groove is connected with the cavity, and the receiving groove is used to receive a blank, and the side wall of the receiving groove is provided with an adjustment hole, and the axis of the adjustment hole is perpendicular to the axis of the cavity, and the positioning push rod is passed through the adjustment hole, and the positioning push rod moves in the adjustment hole and abuts against the blank to fix the blank at a position facing the cavity. The present invention can center blanks of different diameters by arranging a fixed retaining ring and a positioning push rod in the drawing die, and by adjusting the length of the positioning push rod in the fixed retaining ring, so that the drawing die can match blanks of various sizes, and better realize the drawing of formed parts of different heights.

Description

Technical Field

[0001] The invention belongs to the field of tantalum alloy manufacturing, and in particular relates to a tantalum alloy drawing die and a tantalum alloy sticking die production method. Background Art

[0002] Tantalum and tantalum alloys are one of the most important high temperature and corrosion resistant functional materials in modern industry. Currently, they are mainly used to make tantalum capacitors. Deep drawing is an important process for forming thin-walled tantalum alloy containers and other shell parts. The problem of die sticking and wear is a major problem in the deep drawing of tantalum alloy thin-walled components. In order to observe the die sticking phenomenon, researchers often use a drawing die to draw tantalum materials in order to obtain a sticking die and analyze the mechanism of die sticking.

[0003] At present, in the process of deep drawing of tantalum materials, general dies use positioning grooves with limited diameters to ensure centering during deep drawing. This structure only allows one diameter of billet to be centered, and the size restriction in the experiment is extremely single. Once different depths of drawing are desired, the positioning grooves will not work. Therefore, different dies need to be replaced when deep drawing billets of different diameters. This situation makes the processing cost of tantalum capacitors high. Summary of the invention

[0004] The purpose of the present invention is to provide a tantalum alloy drawing die and a tantalum alloy sticking die production method, wherein the drawing die can center dies of different sizes, thereby better realizing the drawing of formed parts of different heights.

[0005] In a first aspect, the present invention provides a tantalum alloy drawing die for drawing tantalum alloy, the tantalum alloy drawing die comprising: an upper insert, a fixed retaining ring and a positioning push rod, the upper insert comprising a first surface and a second surface opposite to each other, the upper insert is provided with a cavity, the cavity passes through the first surface and the second surface, the fixed retaining ring is arranged on the first surface, the fixed retaining ring is provided with a receiving groove, the receiving groove is connected with the cavity, the receiving groove is used to receive a blank, the side wall of the receiving groove is provided with an adjustment hole, the axis of the adjustment hole is perpendicular to the axis of the cavity, the positioning push rod is passed through the adjustment hole, the positioning push rod moves in the adjustment hole and abuts against the blank to fix the blank at a position opposite to the cavity.

[0006] In one embodiment, the positioning push rod includes a sliding rod and a fixed head, the sliding rod is inserted into the adjustment hole, and the fixed head is arranged at one end of the sliding rod located in the accommodating groove to be abutted and fixed to the blank.

[0007] In one embodiment, the number of the positioning push rods is at least two, at least two of the positioning push rods are symmetrically arranged about the axis of the cavity, and the number of the adjustment holes is the same as the number of the positioning push rods.

[0008] In one embodiment, the tantalum alloy drawing die further includes a punch, which is used to extend into the cavity to draw the blank. When the punch is located in the cavity, the spacing distance between the punch and the inner wall of the cavity is less than the thickness of the blank before processing.

[0009] In one embodiment, the punch includes a drawing portion, and the length of the drawing portion along the axial direction of the cavity is greater than or equal to the sum of the height of the cavity and the maximum height of the blank when it reaches the forming limit.

[0010] In one embodiment, the tantalum alloy drawing die further includes a lower insert, which is disposed on the second surface and is provided with a demolding cavity, wherein a projection of the demolding cavity on the second surface surrounds the periphery of a projection of the cavity on the second surface.

[0011] In one embodiment, the tantalum alloy drawing die also includes a die template, the die template is provided with a mounting hole, the upper insert and the lower insert are both arranged in the mounting hole, and the upper insert and the lower insert are both detachably connected to the die template.

[0012] In a second aspect, the present invention further provides a method for producing a tantalum alloy sticky mold, comprising:

[0013] A tantalum alloy drawing die is provided, the tantalum alloy drawing die comprises an upper insert, a fixed retaining ring and a positioning push rod, the upper insert comprises a first surface and a second surface opposite to each other, the upper insert is provided with a cavity, the cavity passes through the first surface and the second surface, the fixed retaining ring is arranged on the first surface, the fixed retaining ring is provided with a receiving groove, the receiving groove is communicated with the cavity, the receiving groove is used to receive a blank, the side wall of the receiving groove is provided with an adjustment hole, the axis of the adjustment hole is perpendicular to the axis of the cavity, and the positioning push rod is passed through the adjustment hole;

[0014] Put the blank into the receiving groove, push the positioning push rod, and the positioning push rod moves in the adjustment hole and abuts against the blank to fix the blank at a position facing the cavity;

[0015] Pushing the punch to deform the blank into a formed piece of a preset height;

[0016] Continue to push the punch to complete demoulding of the formed part.

[0017] In one embodiment, when observing the die sticking phenomenon of the same blank at different drawing heights, the method further comprises:

[0018] Placing the blank into the tantalum alloy drawing die, pushing the punch to deform the blank into a formed piece of a first height, and demolding the blank;

[0019] The formed part of the first height is placed in the tantalum alloy drawing die, and the punch is pushed to deform the formed part of the first height into a formed part of the second height, and then demolding is performed.

[0020] In one embodiment, when observing the influence of different mold materials on the mold sticking of the blank, the method further includes:

[0021] replacing the upper insert made of a different material;

[0022] The blank is placed in the tantalum alloy drawing die, and the punch is pushed to deform the blank into a formed part of a first height.

[0023] The present invention arranges a fixed retaining ring and a positioning push rod in the drawing die, and by adjusting the length of the positioning push rod in the fixed retaining ring, the blanks of different diameters can be centered, so that the drawing die can match blanks of various sizes. The centered blank also reduces the occurrence of wrinkling during the drawing process, which is more conducive to observing the die sticking phenomenon. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 An assembly diagram of a tantalum alloy drawing die according to an embodiment;

[0026] Figure 2 An exploded view of a tantalum alloy drawing die according to an embodiment;

[0027] Figure 3 for Figure 1 A cross-sectional view of the tantalum alloy drawing die along the AA direction shown;

[0028] Figure 4 for Figure 1 A cross-sectional view of the tantalum alloy drawing die along the BB direction shown;

[0029] Figure 5 A schematic diagram of the partial structure of a tantalum alloy drawing die according to an embodiment;

[0030] Figure 6A flowchart of a tantalum alloy die-bonding production method according to an embodiment;

[0031] Figure 7 A flow chart of a tantalum alloy die bonding production method according to another embodiment;

[0032] Figure 8 The present invention is a flow chart of a method for producing a tantalum alloy bonding mold according to another embodiment. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The embodiment of the present invention provides a tantalum alloy drawing die, please refer to Figure 1 and Figure 2 The tantalum alloy drawing die includes a stamping assembly 10, a forming assembly 20 and a demolding assembly 30 which are sequentially installed and fixed, wherein the stamping assembly 10 includes a blank holder 11 and a punch 12, the forming assembly 20 includes a die template 21, the punch 12 is inserted through the blank holder 11 and penetrates into the die template 21. The demolding assembly 30 includes a bottom cover support plate 31, the die template 21 is arranged on the surface of the bottom cover support plate 31 to fix the forming assembly 20 on the demolding assembly 30, the blank holder 11 is arranged on the side of the die template 21 facing away from the bottom cover support plate 31, and is fixed to the die template 21 by a first bolt 51 to fix the stamping assembly 10 and the forming assembly 20. The tantalum capacitor drawing die in this embodiment also includes a first bolt 51, the first bolt 51 is inserted through the bottom cover support plate 31 and the die template 21, and the first bolt 51 is an M8x25 hexagonal bolt. It can be understood that in other embodiments, bolts of other specifications can also be used for fixing. The die template 21 and the blank holder 11 may also be fixed with bolts, which is not limited in this embodiment.

[0035] Specifically, the forming component 20 also includes an upper insert 22. A mounting hole is opened on the die template 21. The upper insert 22 is arranged in the mounting hole and is detachably connected to the die template 21. By making the upper insert 22 detachably connected to the die template 21, due to the small size of the upper insert 22, when observing the influence of different mold materials on the sticking of tantalum alloy, it can be achieved by replacing the upper insert 22 made of different materials. Compared with the method of cutting the mold cavity made of different materials for sticking observation, the die template 21 part can be retained, saving processing costs.

[0036] The upper insert 22 includes a first surface S1 and a second surface S2 facing each other. The first surface S1 is provided with an opening, which penetrates the first surface S1 and the second surface S2 to form a cavity K1, and the cavity K1 is used to accommodate the blank 40. The stamping assembly 10 includes a punch 12. When the blank 40 is drawn, the punch 12 is aligned with the cavity K1 and extends into the cavity K1 to apply pressure to the blank 40 toward the side where the bottom cover support plate 31 is located. The blank 40 is formed into a formed part with a preset height under the action of the punch 12. It can be understood that in this embodiment, the blank 40 is a tantalum alloy thin plate, and the punch 12 includes a drawing portion 121 and a pressing portion 122 connected to each other. The drawing portion 121 and the pressing portion 122 can be an integrated structure or a detachable connection. During the process of deep drawing the blank 40 , pressure or tension is applied to the pressing portion 122 to adjust the height of the deep drawing portion 122 and the deep drawing portion 121 extending into the cavity K1 , and further, the height of the formed part can be controlled.

[0037] Please also read Figure 3 and Figure 4 , an interference fit is adopted between the punch 12, the blank 40 and the upper insert 22. That is, when the drawing portion 122 is located in the cavity K1, the spacing distance between the drawing portion 122 and the side wall of the cavity K1 is less than the thickness of the blank 40. The following is an example in which the cross-sections of the drawing portion 122 and the cavity K1 are both circular. The cross-sectional diameter of the punch 12 is represented by d, the cross-sectional diameter of the cavity K1 is represented by D1, and the thickness of the blank 40 is represented by h. Then, the relationship between the drawing portion 122, the blank 40 and the cavity K1 is satisfied: D1-d1<h. For example, if the diameter d1 of the punch 12 is 6mm, the thickness h of the blank 40 is 0.2mm, and there is no gap, the diameter D1 of the cavity K1 should be 6.4mm, and in this embodiment, an interference fit is adopted to reduce its proportion by 5%, that is, the final cavity K1 diameter D1 thickness is 6.38mm. When the drawing die satisfies the above relationship, during the drawing process, when the punch 12 applies pressure to the blank 40, the punch 12 and the upper insert 22 extrude the blank 40, and there is friction between the upper insert 22 and the blank 40. By adopting an interference fit among the punch 12, the blank 40 and the upper insert 22, the fitting clearance is reduced, so that the friction between the blank 40 and the upper insert 22 is increased, and it is easier to stick to the die. In addition, the formed part processed by the mold provided by the present invention does not have a flange area, saving processing materials.

[0038] In addition, in the present invention, the upper insert 22 is made of a mold material that is easy to stick to the mold, such as aluminum bronze, tungsten steel, and related mold coating mixed materials. These materials will interact with the tantalum alloy sheet at the microstructure, i.e., atomic level, during the deep drawing process to form a greater friction force, thereby making it easier to stick to the mold.

[0039] The present invention performs deep drawing of the blank 40 by arranging a structure in which a punch 12 and an upper insert 22 cooperate with each other in the drawing die, and makes the spacing distance between the punch 21 and the upper insert 22 smaller than the thickness of the blank 40. Therefore, during the drawing process, the friction between the punch 12, the upper insert 22 and the blank 40 is increased, making it easier for the blank 40 to stick to the die, which is beneficial to saving the usage of the blank 40 and the number of processing times in the study of observing the sticking phenomenon of tantalum alloys, thereby reducing the processing cost.

[0040] In one embodiment, please refer to Figure 2 and Figure 4 The forming assembly 20 further includes a lower insert 23 and a second bolt 52. The lower insert 23 is disposed on the second surface S2 of the upper insert 22 and is accommodated in the mounting hole. The upper insert 22 and the lower insert 23 are provided with mutually communicating fixing holes at corresponding positions. The second bolt 52 is passed through the fixing holes to fix the upper insert 22 and the lower insert 23. Similarly, the lower insert 23 is detachably connected to the die template 21. Since the lower insert 23 and the upper insert 22 need to be matched correspondingly, by making the lower insert 23 detachably connected to the die template 21, the lower insert 23 can be replaced at the same time as the upper insert 22 is replaced. In this embodiment, the second bolt 52 is an angle bolt with a specification of M1.6x16. In other embodiments, it can also be specifically designed according to the structure and size of the upper insert 22 and the lower insert 23. The lower insert 23 is also provided with a demoulding cavity K2, the center line of which is aligned with the center line of the mold cavity K1, so that the demoulding cavity K2 is connected with the mold cavity K1.

[0041] The length d2 of the drawing portion 122 along the axial direction of the cavity K1 is greater than or equal to the sum of the height H1 of the cavity K1 and the maximum height H2 of the blank 40 when it reaches the forming limit. Specifically, when pressure is applied to the punch 12 to move it toward the bottom cover support plate 31, the punch 12 applies pressure to the blank 40, so that the blank 40 is drawn and deformed toward the bottom cover support plate 31 in the axial direction of the cavity K1 to form a formed part with a preset height, until the formed part is separated from the cavity K1 and the blank 40 reaches the maximum height H2 at the forming limit. By making the length d2 of the drawing portion 122 along the axial direction of the cavity K1 greater than or equal to the sum of the height H1 of the cavity K1 and the maximum height H2 of the blank 40 when it reaches the forming limit, it is ensured that the purpose of separating the formed part from the cavity K1 can be achieved by pushing the punch 12, making the demolding process simpler and more efficient.

[0042] In this embodiment, the projection of the demolding cavity K2 on the second surface S2 surrounds the periphery of the projection of the mold cavity K1 on the second surface S2, that is, the minimum dimension of the cross section of the demolding cavity K2 is greater than the maximum dimension of the cross section of the mold cavity K1. Taking the case that the mold cavity K1 and the demolding cavity K2 are both cylindrical cavities, the maximum dimension of the cross section of the mold cavity K1 is the cross section diameter D1 of the mold cavity K1, and the cross section dimension of the demolding cavity K2 is the cross section diameter D2 of the demolding cavity K2. By making D1 smaller than D2, the molded part can have an air gap between the lower insert 23 after entering the demolding cavity K2 from the mold cavity K1, so as to prevent the friction between the lower insert 23 and the molded part from hindering the demolding of the molded part. In addition, a discharge hole K3 is also provided on the bottom cover support plate 31, and the discharge hole K3 is arranged opposite to the demolding cavity K2, and the discharge hole K3 is also connected to the outside. Similarly, the minimum dimension D3 of the cross section of the discharge hole K3 is greater than the maximum dimension D2 of the cross section of the demolding cavity K2, so that the formed part can sequentially enter the demolding cavity K2 from the mold cavity K1, and then pass through the discharge hole K3 from the demolding cavity K2, and finally leave the deep drawing mold for mold sticking observation. By making the minimum dimension D3 of the cross section of the discharge hole K3 greater than the maximum dimension D2 of the cross section of the demolding cavity K2, there is an air gap between the formed part and the bottom cover support plate 31 when the formed part passes through the discharge hole K3, which can prevent the friction between the bottom cover support plate 31 and the formed part from hindering the demolding of the formed part. It can be understood that the shapes of the cross sections of the mold cavity K1, the demolding cavity K2 and the discharge hole K3 include but are not limited to circles, and can also be other shapes such as quadrilaterals and pentagons, and the shapes of the cross sections of the mold cavity K1, the demolding cavity K2 and the discharge hole K3 can be the same or different. By setting a lower insert 23 in the drawing die, and setting a demolding cavity K2 connected to the cavity K1 on the lower insert 23, and the minimum size of the cross section of the demolding cavity K2 is larger than the maximum size of the cross section of the cavity K1, the problem of difficulty in demolding caused by the small gap of the upper insert 22 can be solved when the molded part is demolded, so that the molded part can be easily demolded and will not be stuck in the forming component 20.

[0043] In one embodiment, please refer to Figures 1 to 3The stamping assembly 10 further includes a fixed retaining ring 13 and a positioning pin 14. The surface of the die template 21 facing away from the bottom cover support plate 31 is a third surface S3, and the third surface S3 is flush with the first surface S1 of the upper insert 22. The fixed retaining ring 13 is fixed to the third surface S3 by the positioning pin 14. The fixed retaining ring 13 includes at least one set of symmetrically arranged fixing parts 131, and a positioning hole 132 is provided on the fixing part 131. The positioning pin 14 is arranged in the positioning hole 132 to locate and fix the relative position of the die template 21 of the fixed retaining ring 13. By symmetrically arranging the fixing parts 131, the fixed retaining ring 13 can have higher stability. In this embodiment, the fixed retaining ring 13 includes four fixing parts 131, and they are symmetrically arranged in pairs, wherein two symmetrically arranged fixing parts 131 are provided with fixing holes, and the number of the positioning pins 14 is the same as the number of the fixing holes. It can be understood that in other embodiments, the number of fixing parts 131 can also be designed according to actual needs.

[0044] Please also read Figure 2 and Figure 5 The fixed retaining ring 13 also includes a receiving groove 133, which is arranged corresponding to the cavity K1. The receiving groove 133 is recessed from the surface of the fixed retaining ring 13 facing away from the concave die template 21 to the third surface S3, and is arranged coaxially with the cavity K1. In this embodiment, the bottom of the receiving groove 133 is circular, and the diameter of the receiving groove 133 is larger than the diameter of the cavity K1, so that a larger size of blank 40 can be accommodated. A through hole 134 is also provided at the bottom of the receiving groove 133 at a position relative to the cavity K1, and the through hole 134 is connected to the cavity K1, thereby connecting the receiving groove 133 and the cavity K1. The receiving groove 133 is used to accommodate the blank 40. When the punch 12 applies pressure to the blank 40, the blank 40 enters the cavity K1 through the through hole 134 to complete the deep drawing. By setting a fixed retaining ring 13 in the drawing die and setting a receiving groove 133 at a position corresponding to the fixed retaining ring 13 and the cavity K1, the fixed retaining ring 13 is positioned and the blank 40 is placed in the receiving groove 133, thereby achieving preliminary centering and fixing of the blank 40.

[0045] In one embodiment, please refer to Figure 1 , Figure 2 and Figure 5The stamping assembly 10 also includes a positioning push rod 15. The side wall of the fixed receiving groove 133 is provided with an adjustment hole, and the axis of the adjustment hole is perpendicular to the axis of the cavity K1. The positioning push rod 15 is inserted into the adjustment hole and moves in the adjustment hole to abut against the blank 40, thereby fixing the blank 40 at a position directly opposite to the cavity K1. By setting a positioning push rod in the drawing die and adjusting the length of the positioning push rod in the fixed retaining ring 13, the blanks 40 of different diameters can be centered, so that the drawing die can match a variety of different sizes of blanks 40, and better realize the drawing of formed parts of different heights. In addition, the blank 40 after centering also reduces the occurrence of wrinkling during the drawing process, which is more conducive to observing the sticking phenomenon.

[0046] In one embodiment, please refer to Figure 1 , Figure 2 and Figure 5 , the number of positioning push rods 15 is at least two, and the plurality of positioning push rods 15 are symmetrically arranged about the axis direction of the cavity K1. In this embodiment, the number of positioning push rods 15 is set to 4, and the 4 positioning push rods 15 are symmetrically arranged in pairs about the axis of the cavity K1, and are correspondingly penetrated in the 4 adjustment holes. The positioning push rod 15 includes a sliding rod 151 and a fixed head 152 that are connected to each other. The sliding rod 151 is penetrated in the adjustment hole and can move along the axis direction of the adjustment hole. The fixed head 152 is located at one end of the sliding rod 151 located in the receiving groove 133 to fix the blank 40. In the pre-stamping stage of the blank 40, after the blank 40 is set in the receiving groove 133, the positioning push rod 15 can be pushed so that the fixed head 152 is abutted and fixed to the blank 40, so as to achieve the purpose of centering the blank 40. When the diameter of the blank 40 is large, the sliding rod 151 can be pulled to increase the length of the positioning push rod 15 extending into the receiving groove 133 to complete the centering of the large diameter blank 40; when the diameter of the blank 40 is small, the sliding rod 151 can be pushed to increase the length of the positioning push rod 15 extending into the receiving groove 133 to complete the centering of the small diameter blank 40. It can be understood that in other embodiments, the number of positioning push rods 15 can also be 3, 5, etc., which is not specifically limited in this embodiment. By arranging at least two positioning push rods 15 in the drawing die, and symmetrically arranging the at least two positioning push rods about the axis of the cavity, the forces exerted by the positioning push rods on the blank 40 are balanced with each other, which is more conducive to achieving the centering of the blank 40.

[0047] Please also read Figure 2 and Figure 6 The embodiment of the present invention also provides a method for forming a tantalum alloy sticking mold production method to facilitate the observation and research of the sticking mold phenomenon, which includes:

[0048] Step S1: providing a tantalum alloy drawing die, the tantalum alloy drawing die comprising an upper insert 22, a fixed retaining ring 13 and a positioning push rod 15, the upper insert 22 comprising a first surface S1 and a second surface S2 opposite to each other, the upper insert 22 is provided with a cavity K1, the cavity K1 passes through the first surface S1 and the second surface S2, the fixed retaining ring 13 is arranged on the first surface S1, the fixed retaining ring 13 is provided with a receiving groove 133, the receiving groove 133 is communicated with the cavity K1, the receiving groove 133 is used to receive the blank 40, the side wall of the receiving groove 133 is provided with an adjusting hole, the axis of the adjusting hole is perpendicular to the axis of the cavity K1, and the positioning push rod 15 is passed through the adjusting hole;

[0049] Step S2: placing the blank 40 into the receiving groove 133, pushing the positioning push rod 15, and the positioning push rod 15 moves in the adjustment hole and abuts against the blank 40 to fix the blank 40 at a position facing the cavity K1;

[0050] Step S3: pushing the punch 12 to deform the blank 40 into a formed piece with a preset height;

[0051] Step S4: Continue to push the punch 12 to complete demoulding of the formed part.

[0052] The tantalum alloy sticking mold production method provided in the embodiment of the present invention includes a stamping stage, a forming stage and a demolding stage.

[0053] In the pre-stamping stage, step S2 is specifically as follows: first, remove all stamping components 10, and place the blank 40 on the upper insert 22, and then install the fixed retaining ring 13 based on the position of the positioning pin 14, and push the positioning push rod 15 in the axial direction of the adjustment hole to complete the centering of the blank 40. Since the positioning push rod 15 can be freely extended and retracted, the diameter of the blank 40 can be changed within a certain range.

[0054] Next, continue to install the blank holder 11 based on the position of the positioning pin 14, tighten the fasteners 53 at the four corners. The present invention uses M8x25 hexagonal bolts, and place the punch 12 on the blank 40 through the positioning hole 132 on the blank holder 11.

[0055] In the forming stage, step S3 specifically includes: using a press to push the punch 12 to push the blank 40 downward, and drawing it into a columnar formed part at the upper insert 22. As the diameter of the blank 40 changes and the punch 12 descends to different depths, the blank 40 will be extruded into columnar formed parts of different heights.

[0056] In the demolding stage, step S4 is specifically as follows: push the punch 12, and as the punch 12 is pressed down to the forming limit, the formed part will pass through the lower insert 23 until it is separated from the upper insert 23, and then the formed part is taken out. Since the size of the demolding cavity K2 at the lower insert 23 is larger than the size of the cavity K1 when the upper insert 22 is drawn, the formed part can be demolded from the forming component 20 relatively easily, and smoothly stay at the discharge hole K3 of the bottom cover support plate 31, so as to obtain a tantalum capacitor formed part that is easy to observe the sticking film. By adopting the tantalum alloy sticking mold production method provided in the embodiment of the present invention, the centering of blanks of various diameters can be achieved by adjusting the positioning push rod without changing the mold, thereby improving the efficiency of sticking mold observation and saving the cost of sticking mold observation.

[0057] In one embodiment, please refer to Figure 2 and Figure 7 When the die sticking phenomenon of the same blank 40 at different drawing heights is observed, the tantalum alloy die sticking production method includes:

[0058] Step S31: placing the blank into a tantalum alloy drawing die, pushing the punch to deform the blank into a formed part of a first height, and demolding the blank;

[0059] Step S32: Place the formed part of the first height into the tantalum alloy drawing die, push the punch, so that the formed part of the first height is deformed to the formed part of the second height, and demold. Specifically, when observing the die sticking phenomenon of different drawing heights of the same blank 40, it can be achieved by repeatedly completing steps S1 to S4 for the same blank 40 for many times. For example, firstly cycle through steps S1 to S4 once to obtain a formed part of the first height, and observe the die sticking phenomenon of the formed part of the first height and record relevant parameters; then, put the formed part of the first height back into the drawing die, repeat steps S1 to S4, obtain a formed part with a second height, and observe the die sticking phenomenon of the formed part of the second height and record relevant parameters; finally, by comparing the parameters recorded twice, the change of the die sticking phenomenon of different drawing heights of the same blank 40 is obtained. It can be understood that in other embodiments, the number of cycles can be determined according to the number of different heights to be studied. Each time the steps S1 to S4 are cycled once, the heights of the formed parts obtained after the blank 40 is drawn are all different, so that the die sticking phenomenon at different drawing heights can be observed. The die sticking production method provided in this embodiment realizes the processing of metal forming blanks 40 of different heights without flanges from a single thickness sheet material, so as to study the die sticking phenomenon at different drawing heights of the same blank 40, which greatly saves research costs.

[0060] In one embodiment, please refer to Figure 2 and Figure 8 When the influence of different mold materials on the sticking of the blank 40 is observed, the tantalum alloy sticking mold production method includes:

[0061] Step S5: replacing the upper insert 22 made of a different material;

[0062] Step S6: Place the blank 40 into the tantalum alloy drawing die, and push the punch 12 to deform the blank 40 to a formed part of the first height. Specifically, when it is necessary to study the effect of different mold materials on the sticking of the blank 40, it is necessary to study the sticking of the tantalum alloy material in different molds. First, an upper insert 22 made of a material can be selected and installed in the drawing die, and then steps S1 to S4 are repeated; secondly, the upper insert 22 in the drawing die is removed, and an upper insert 22 made of another material is replaced and installed in the drawing die, and then steps S1 to S4 are repeated again until the mold materials to be studied are all involved in the forming process, and then the formed parts formed by the drawing of the upper inserts 22 made of different materials are observed.

[0063] In this embodiment, the blank 40 is deep drawn by replacing the upper insert 22 to study the effect of different mold materials on the mold sticking of the blank 40. Compared with the method of cutting the mold cavity K1 made of different materials for mold sticking observation, the die template 21 part can be retained, saving processing costs.

[0064] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A tantalum alloy drawing die for drawing tantalum alloy, characterized in that: include: A stamping assembly, a forming assembly and a demoulding assembly are sequentially installed and fixed; the stamping assembly includes a blank holder, a fixed retaining ring and a positioning push rod, the forming assembly includes an upper insert, a lower insert and a concave mold template, and the demoulding assembly includes a bottom cover support plate; The upper insert comprises a first surface and a second surface facing each other, the upper insert is provided with a cavity, the cavity passes through the first surface and the second surface, the fixed retaining ring is arranged on the first surface, the fixed retaining ring is provided with a receiving groove, the receiving groove is communicated with the cavity, the receiving groove is used to receive a blank, the side wall of the receiving groove is provided with an adjustment hole, the axis of the adjustment hole is perpendicular to the axis of the cavity, the positioning push rod is passed through the adjustment hole, the positioning push rod moves in the adjustment hole and abuts against the blank, so as to fix the blank at a position directly opposite to the cavity; The die template is provided with a mounting hole, the upper insert and the lower insert are both arranged in the mounting hole and are detachably connected to the die template, and the upper insert and the lower insert are both provided with mutually communicating fixing holes at corresponding positions; the tantalum alloy drawing die further comprises a first bolt, a second bolt and a fastener, the first bolt is passed through the bottom cover support plate and the die template, the second bolt is passed through the fixing hole to install and fix the upper insert and the lower insert, and the fastener is passed through the blank holder and the die template; The lower insert is arranged on the second surface, the lower insert is provided with a demoulding cavity, the accommodating groove is coaxially arranged with the cavity, and the center line of the demoulding cavity is aligned with the center line of the cavity.

2. The tantalum alloy drawing die according to claim 1, characterized in that: The positioning push rod comprises a sliding rod and a fixed head. The sliding rod is inserted into the adjusting hole. The fixed head is arranged at one end of the sliding rod located in the accommodating groove to be abutted and fixed against the blank.

3. The tantalum alloy drawing die according to claim 2, characterized in that: The number of the positioning push rods is at least two, and at least two of the positioning push rods are symmetrically arranged about the axis of the cavity. The number of the adjustment holes is the same as the number of the positioning push rods.

4. The tantalum alloy drawing die according to claim 1, characterized in that: It also includes a punch, which is used to extend into the cavity to draw the blank. When the punch is located in the cavity, the spacing distance between the punch and the inner wall of the cavity is less than the thickness of the blank before processing.

5. The tantalum alloy drawing die according to claim 4, characterized in that: The punch includes a drawing portion, and a length of the drawing portion along the axial direction of the cavity is greater than or equal to the sum of a height of the cavity and a maximum height of the blank when the blank reaches a forming limit.

6. The tantalum alloy drawing die according to claim 1, characterized in that: The projection of the demoulding cavity on the second surface surrounds the periphery of the projection of the mold cavity on the second surface.

7. A method for producing a tantalum alloy mold, characterized in that: include: A tantalum alloy drawing die is provided, the tantalum alloy drawing die comprises a stamping assembly, a forming assembly and a demolding assembly which are sequentially arranged and fixed; the stamping assembly comprises a pressure ring, a fixed retaining ring and a positioning push rod, the forming assembly comprises an upper insert, a lower insert and a concave die template, and the demolding assembly comprises a bottom cover support plate; the upper insert comprises a first surface and a second surface opposite to each other, the upper insert is provided with a cavity, the cavity passes through the first surface and the second surface, the fixed retaining ring is arranged on the first surface, the fixed retaining ring is provided with a receiving groove, the receiving groove is connected to the cavity, the receiving groove is used to receive the blank, the side wall of the receiving groove is provided with an adjusting hole, the axis of the adjusting hole is perpendicular to the axis of the cavity, the positioning push rod passes through The tantalum alloy drawing die further comprises a first bolt, a second bolt and a fastener, the first bolt is passed through the bottom cover support plate and the die template, the second bolt is passed through the fixing hole to install and fix the upper and lower inserts, and the fastener passes through the pressure ring and the die template; the lower insert is arranged on the second surface, the lower insert is provided with a demoulding cavity, the accommodating groove is coaxially arranged with the cavity, and the center line of the demoulding cavity is aligned with the center line of the cavity; Put the blank into the receiving groove, push the positioning push rod, and the positioning push rod moves in the adjustment hole and abuts against the blank to fix the blank at a position facing the cavity; Pushing the punch to deform the blank into a formed piece of a preset height; Continue to push the punch to complete demoulding of the formed part.

8. The method according to claim 7, characterized in that When observing the die sticking phenomenon of the same blank at different drawing heights, the method further comprises: Placing the blank into the tantalum alloy drawing die, pushing the punch to deform the blank into a formed piece of a first height, and demolding the blank; The formed part of the first height is placed in the tantalum alloy drawing die, and the punch is pushed to deform the formed part of the first height into a formed part of the second height, and then demolding is performed.

9. The method according to claim 7, characterized in that: When observing the influence of different mold materials on the sticking of the blank, the method further includes: replacing the upper insert made of a different material; The blank is placed in the tantalum alloy drawing die, and the punch is pushed to deform the blank into a formed part of a first height.

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