CN104001998B - Array micro group electrode preparation method and the device optimized based on negative electrode - Google Patents

Abstract

A method for preparing an array group electrode based on cathode optimization, comprising the following steps: (1) making an array electrode blank; (2) coating a layer of epoxy resin insulating glue on the surface of the group electrode clamp, and the array group electrode blank is exposed; 3) According to the size of the blank structure, design the physical model of the gap electric field for electrochemical machining of array group electrodes, set the processing voltage U, and the electrolyte conductivity parameter κ; prepare the side cylindrical cathode and spherical cathode according to the set parameters; (4) side cylindrical The surface cathode and the array electrode blank are immersed in the electrolyte together, and the experimental processing is carried out based on the simulation analysis parameters. The uniform control of the axial diameter of the tool electrode is realized by adjusting the processing voltage, and the electrochemical preparation of the array micro-group electrode of the required size is realized. And provide an array group electrode preparation device based on cathode optimization. The invention broadens the machinable materials, has the advantages of simple process, high processing efficiency and low cost.

Description

Method and device for preparing array micro-group electrodes based on cathode optimization

technical field

The invention belongs to the technical field of micro-processing and special processing, in particular to a method and device for preparing a micro-group electrode.

Background technique

With the development of aerospace, electronic industry, precision instruments and modern medical devices, components with array micro-pore structures have important application prospects in many fields, such as aero-engine air duct damping sleeves, optical fiber connectors, precision filters, For chemical fiber spinnerets, printer nozzles, printed circuit boards, etc., the diameter of these holes is usually tens to hundreds of microns, the depth is tens of microns to several millimeters, and the number varies from tens to thousands. The processing of such structures is the key to realize their industrial applications. Micro-EDM technology and micro-electrolytic machining technology can process micro-array holes due to their own processing characteristics. However, the preparation of micro-array electrodes is a key link in the realization of these two methods.

The preparation methods of micro-array electrodes include: LIGA technology, UV-LIGA technology, wire electric discharge method, electric spark reverse copy method, electrochemical corrosion method, etc. LIGA technology requires the use of expensive synchronous X-ray generators as light sources, so the cost is very high; although the cost of UV-LIGA technology is lower than that of LIGA technology, its process is still complicated, and LIGA technology and UV-LIGA technology mainly process Copper/nickel and its alloy materials cannot process high-temperature resistant and high-hardness tungsten materials; wire EDM technology can only process square structures; EDM reverse copying has many procedures, complex equipment, low processing efficiency, and serious problems in the middle electrode. loss; the flat plate + semi-cylindrical cathode electrochemical corrosion method can only process row-shaped group electrodes, but is not applicable to array electrodes.

The electrochemical method is based on the principle of anodic dissolution to remove the material. The removal of the material in the processing is carried out in the form of ions. In principle, the removal at the atomic level can be achieved, and the processing accuracy is high; and there is no force in the processing, and the micro tools after processing There is no deformation of the electrode; therefore, the electrochemical method can be used for the preparation of micro-tool electrodes. In the past, the research method [CN100544874C] for the preparation of micro-electrodes by electrochemical corrosion method can realize the processing of row-shaped group electrodes, but there are few reports on the preparation method of array micro-electrodes.

The present invention is produced on the basis of experimental research. Early research experiments have found that when parallel plate tool cathodes are used to process row-shaped group electrodes (FIG. 1), the current density distribution on the electrode surface is shown in FIG. 2.

Contents of the invention

In order to overcome the deficiencies of the existing micro-group electrode preparation methods and devices, such as limited machinable materials, complex processes, low processing efficiency, and high cost, the present invention provides a method for broadening machinable materials, simple process, high processing efficiency, and low cost. A method and device for preparing array micro-group electrodes based on cathode optimization.

The technical solution adopted by the present invention to solve its technical problems is:

A method for preparing an array group electrode based on cathode optimization, the preparation method comprising the following steps:

(1) Fabrication of array electrode blanks: cutting the metal material into an array structure of regular polygonal cross-section, the side length of the cross-section is a, the electrode length L and the spacing d;

(2) The surface of the group electrode fixture is coated with a layer of epoxy resin insulating glue, and the array group electrode blank is exposed;

(3) According to the size of the blank structure, design the physical model of the gap electric field of the array group electrode electrochemical machining, set the processing voltage U, the electrolyte conductivity parameter κ; the radius R of the cylindrical surface of the side cylindrical cathode, and the distance between the axis and the side of the array electrode D1 , the rotation angle α; the spherical radius ΦR of the spherical cathode, the distance D2 between the center of the cathode sphere and the center electrode of the array blank, and the spherical radiation angle β Prepare the side cylindrical cathode and spherical cathode according to the set parameters;

(4) Four side cylindrical cathodes are installed around the group electrode fixture, and a spherical cathode is arranged above the group electrode fixture, and the center of the array of fine group electrode blanks and the center of the spherical cathode are located at the same vertical On-line; the side cylindrical cathode and the array electrode blank are immersed in the electrolyte together, and the experimental processing is carried out based on the simulation analysis parameters. By adjusting the processing voltage, the uniform control of the axial diameter of the tool electrode is realized, and the electrochemical reaction of the array micro-group electrode of the required size is realized. preparation.

Further, in the step (4), combined with online microscope observation and measurement of the diameter change of the tool electrode, the electrochemical preparation of the micro-group electrode of the required size array is realized.

Furthermore, in the step (3), the inner surface of the cylindrical tool cathode and the inner surface of the spherical cathode are coated with a layer of insulating glue.

In the step (3), adopt the finite element optimization method to design the cathode structure: set the objective function Function to be the smallest current density difference between the electrodes on the anode surface, and under the premise of setting the dimensions ΦR, D2 and the spherical radiation angle β, optimize the analysis to obtain the side The radius R of the tool cathode cylinder, the distance D1 from the axis to the side of the array electrode, and the rotation angle α; based on the R, D1 and α obtained from the optimization analysis, the radius of the cathode sphere is optimized again, the distance D2 from the center of the cathode sphere to the center electrode of the array blank, and the spherical surface Radiation angle β; the tool cathode is prepared according to the optimization results.

An array micro-group electrode preparation device based on cathode optimization, including a machine tool, an electrolytic cell, and a processing power supply. The bottom of the inner cavity of the electrolytic cell is provided with a group electrode fixture for placing an array of micro-group electrode blanks to be processed. The group electrode Four side cylindrical cathodes are installed around the fixture, and a spherical cathode is arranged above the group electrode fixture. The center of the array of fine group electrode blanks and the center of the spherical cathode are located on the same vertical line, and the spherical cathode Installed on the machine tool, the spherical cathode and the side cylindrical cathode are connected to the negative pole of the processing power supply, and the array micro-group electrode blank to be processed is connected to the anode of the processing power supply.

Further, a layer of insulating glue is coated on the inner surface of the cylindrical tool cathode, the inner surface of the spherical cathode, and the group electrode fixture.

Furthermore, the device also includes an on-line microscope, the on-line microscope is located on the side of the electrolytic tank, and the side of the electrolytic tank is provided with an observation window.

Compared with the existing processing technology, the present invention has the following advantages:

1) It can process micro-group electrodes with uniform diameter and size, and the group electrode materials can be tungsten, cemented carbide and other materials that cannot be processed by previous processing methods;

2) The diameter of group electrodes is easy to control, and electrodes with large aspect ratio can be processed, which is less limited by processing equipment.

3) The processing efficiency is high, no special template is needed, and multiple electrodes can be formed at one time;

Therefore, the inventive method has simple technological process, good realizability and operability, and low cost.

Description of drawings

Fig. 1 is a schematic diagram of a row-shaped group electrode of the existing parallel-plate cathode electrochemical machining.

Fig. 2 is a trend diagram of current density distribution on the electrode surface during processing in Fig. 1 .

Fig. 3 is a schematic diagram of the structure of the preparation of array micro-group electrodes based on cathode optimization of the present invention.

Fig. 4 is a structure diagram of a cathode optimization array micro-group electrode.

Fig. 5 is a flow chart of the preparation method of array micro-group electrodes.

Fig. 6 is a regular diagram of the change of group electrode diameter with processing time.

Fig. 7 is a structure diagram of the processed array micro-group electrodes.

Fig. 8 is a cross-sectional view of blanks of array group electrodes with various cross-sections.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings.

Referring to Figures 3 to 8, a method for preparing array group electrodes based on cathode optimization includes the following steps:

(1) Fabrication of the array electrode blank: cut the metal material into a regular polygonal cross-sectional display structure, the side length of the cross-section is a, the electrode length L, and the spacing d.

(2) The surface of the group electrode base is coated with a layer of epoxy resin insulating glue to keep the regular polygon cross-section display group electrode blank exposed.

(3) According to the size of the blank structure, design the physical model of the gap electric field in the electrochemical machining of array group electrodes, set the processing voltage U and the electrolyte conductivity parameter κ, use the finite element optimization method to design the cathode structure (as shown in Figure 4), and set the objective function Function is the smallest difference in current density between electrodes on the anode surface. Under the premise of setting the dimensions ΦR, D2 and spherical radiation angle β, the optimization analysis obtains the cylindrical surface radius R of the side cylindrical cathode, the distance between the axis and the side of the array electrode D1, and the rotation angle α ;Based on the R, D1 and α obtained by the optimization analysis, the spherical radius ΦR of the spherical cathode is optimized again, the distance D2 between the center of the cathode sphere and the center electrode of the array blank, and the spherical radiation angle are obtained;

(4) Four side cylindrical cathodes are installed around the group electrode fixture, and a spherical cathode is arranged above the group electrode fixture, and the center of the array of fine group electrode blanks and the center of the spherical cathode are located at the same vertical On-line; the side cylindrical cathode and the array group electrode blank are immersed in the electrolyte together, and the experimental processing is carried out based on the simulation analysis parameters, and the tool electrode axial diameter is controlled by adjusting the processing voltage, combined with the online microscope observation and measurement of the tool electrode diameter Changes to realize the electrochemical preparation of micro-group electrodes with required size arrays.

The cross section of the array electrode blank of the present invention is square, regular triangle, regular pentagon or regular hexagon. As shown in Figure 8, (a) is a regular triangle, (b) is a square; (c) is a regular hexagon; (d) is a regular pentagon.

The flow chart of the electrochemical machining method of the spherical cathode optimally arrayed fine group electrodes involved in the present invention is shown in Fig. 5 .

In the present invention, by adopting cylindrical and spherical tool cathodes, by optimizing the diameter of the cylindrical surface, the distance between the axis and the side of the array group electrode, the rotation angle, the diameter of the sphere, the diffusion angle, and the distance from the tip of the group electrode, a uniform diameter and size can be prepared. Array micro-group electrode structure for application in micro-fabrication.

Secondly, the present invention adopts the arrangement of the spherical tool cathode on the top and the workpiece on the bottom, which effectively avoids the generation of air bubbles on the surface of the group electrode by the tool cathode, inhibits the removal of the surface material of the group electrode, and affects the shape and surface quality of the group electrode.

The inner surface of the cylindrical tool cathode, the inner surface of the spherical cathode, and the group electrode base are coated with a layer of insulating glue, which can increase the processing speed under the same power condition. At the same time, the insulating layer shields part of the electric field, which is helpful for cathode optimization. Uniformity of electric field distribution in the design.

The invention adopts on-line microscope observation and on-line measurement of the shape change rule and size of the group electrodes, which can control the electrode forming in real time and reduce the failure rate of group electrode preparation.

Referring to FIG. 3 , a cathode-optimized array micro-group electrode preparation device includes a machine tool 1, an electrolytic cell 4 and a processing power supply 7. The bottom of the inner cavity of the electrolytic cell 4 is provided with a blank for placing the micro-group electrode blank to be processed. Group electrode fixture 3, four side cylindrical surface cathodes 5 are installed around the group electrode fixture 3, spherical cathode 6 is arranged above the group electrode fixture 3, the center of the micro group electrode blank of the array is in contact with the spherical cathode The center of 6 is located on the same vertical line, the spherical cathode 6 is installed on the machine tool 1, the spherical cathode 6 is connected to the negative pole of the processing power supply 7, and the array micro-group electrode blank to be processed is connected to the Anode connection for processing power supply 7.

Further, the device also includes an on-line microscope 8, the on-line microscope 8 is located on the side of the electrolytic tank 4, and the side of the electrolytic tank 4 is provided with an observation window.

Furthermore, a layer of insulating glue is coated on the inner surface of the cylindrical tool cathode, the inner surface of the spherical cathode, and the group electrode fixture.

In this embodiment, tungsten is selected as the raw material, and the end of the tungsten block is processed into a cross-sectional size of 0.5mm×0.5mm, a pitch of 1mm, a height of 5mm, and a 3×3 array form by wire electric discharge cutting, as shown in Figure 3 Group electrode 2 structure. Next, install the 3×3 array on the group electrode fixture in the electrolyte tank, and connect the anode of the processing power supply. The spherical tool cathode is installed on the Z axis of the machine tool, connected to the workpiece anode, and the machine tool drives the tool cathode to move. According to the finite element optimization conditions (When optimizing, set the processing voltage to 6V, and the conductivity of the electrolyte), adjust the relative position between the tool cathode and the group electrode, take D1=33.6mm, R=30mm, α=8.9°, D2=25.6mm, ΦR=16.8mm, β=37°.

The electrolyte tank is filled with NaOH with a concentration of 4%, and the electrolyte is immersed in the cathode of the cylindrical/spherical tool and the electrode blank of the array group, and the online microscope system is turned on, and the processing power supply is connected and the processing voltage is set to 6V. The microscope system detects and records the diameter of the fine electrode The size and shape changes. It is observed that the material at the edge dissolves first. As the processing progresses, the cross-sectional shape of the group electrode gradually tends to be circular, and then the electrode diameter gradually decreases with the processing time. The change law is shown in Figure 6. When the diameter size meets the required requirements, cut off the processing power supply to obtain the required array of micro-group electrodes, the structure of which is shown in Figure 7.

Claims (7)

1. an array group electrode preparation method of optimizing based on negative electrode, is characterized in that: described preparation method comprises the following steps:

(1) array group electrode blank is made: metal material is cut into the array structure of equilateral polygon section, its cross section size dimension is a, electrode length L and spacing d;

(2) group's electrode holder surface applies one deck epoxy resins insulation glue, and described array group electrode blank is exposed;

(3), according to blahk structure size, array of designs group's electrode electro Chemical machining gap electric field physical model, sets machining voltage U, electrolytic conductivity parameterκ; The face of cylinder radius R of the face of cylinder, side negative electrode, axial line distance array group electrode blank lateral distance D1, anglec of rotation α; The spherical radius Φ R of sphere negative electrode, negative electrode centre of sphere distance arrays group electrode blank central electrode distance B 2, spherical radiation angleβ，Prepare the face of cylinder, side negative electrode and sphere negative electrode according to setup parameter;

(4) surrounding of described group electrode holder is installed the face of cylinder, four sides negative electrode, above described group's electrode holder, arranges sphere negative electrode, being centered close on same plumb line of the center of described array group electrode blank and described sphere negative electrode; The face of cylinder, side negative electrode is submerged into electrolyte together with array electrode blank, test processing based on sunykatuib analysis parameter, by regulating machining voltage implementation tool electrode axis to the control of diameter dimension uniformity, realize the preparation of required size array micro group electrode electro Chemical.

2. a kind of array group electrode preparation method of optimizing based on negative electrode as claimed in claim 1, it is characterized in that: in described step (4), change to diameter in conjunction with online microscopic examination survey tool electrode axis, realize the preparation of required size array micro group electrode electro Chemical.

3. a kind of array group electrode preparation method of optimizing based on negative electrode as claimed in claim 1 or 2, is characterized in that: in described step (3), face of cylinder tool cathode inner surface, sphere cathode inner surface apply one deck insulating cement.

4. a kind of array group electrode preparation method of optimizing based on negative electrode as claimed in claim 1 or 2, it is characterized in that: in described step (3), adopt finite element optimization method design cathode construction: Offered target function F unction is the poor minimum of the each electrode current density of anode surface, setting size Φ R, D2 and spherical radiation angleβUnder prerequisite, optimize analysis and obtain the tool cathode face of cylinder, side radius R, axial line distance array group electrode blank lateral distance D1, anglec of rotation α; Analyze based on optimizing R, the D1 and the α that obtain, then suboptimization obtains negative electrode spherical radius Φ R, negative electrode centre of sphere distance arrays group electrode blank central electrode distance B 2, spherical radiation angleβ; Prepare tool cathode according to optimum results.

5. an array micro group electrode preparation facilities of optimizing based on negative electrode, comprise lathe, electrolytic cell and processing power source, it is characterized in that: the intracavity bottom of described electrolytic cell is provided with the group's electrode holder for placing array micro group electrode blank to be processed, the surrounding of described group's electrode holder is installed the face of cylinder, four sides negative electrode, above described group's electrode holder, arrange sphere negative electrode, being centered close on same plumb line of the center of described array micro group electrode blank and described sphere negative electrode, described sphere negative electrode is arranged on described lathe, described sphere negative electrode, the face of cylinder, side negative electrode is connected with the negative pole of described processing power source, the anodic bonding of described array micro group electrode blank to be processed and described processing power source.

6. a kind of array micro group electrode preparation facilities of optimizing based on negative electrode as claimed in claim 5, is characterized in that: apply one deck insulation glue-line at described face of cylinder tool cathode inner surface, sphere cathode inner surface, group's electrode holder.

7. a kind of array micro group electrode preparation facilities of optimizing based on negative electrode as described in claim 5 or 6, it is characterized in that: described device also comprises online microscope, described online microscope is positioned at the side of described electrolytic cell, and the side of described electrolytic cell is provided with observation window.