Ultrasonic coordinated air film shielding assisted micro-electrolysis processing method and device

Abstract

A method for processing ultrasonic-assisted air film shielding-assisted micro-electrolysis, the workpiece is tightly connected to the ultrasonic amplitude transformer of an ultrasonic vibration device, the workpiece is connected to the positive electrode of a power supply through the ultrasonic vibration device, the needle-shaped tool electrode used is clamped and fixed in the nozzle by a tool electrode chuck, the lower end of the tool electrode extends from the liquid outlet of the nozzle, and the tool electrode is connected to the negative electrode of the power supply through the nozzle; during processing, the workpiece is fixed, the machine tool drives the nozzle and the tool electrode to feed toward the workpiece, and a certain processing gap is maintained between the workpiece and the tool electrode, and the high-speed electrolyte coated with a high-pressure gas film is sprayed onto the workpiece under ultrasonic action, so as to achieve stable and efficient processing and obtain the desired microstructure. And a device for ultrasonic-assisted air film shielding-assisted micro-electrolysis processing is provided, including an ultrasonic vibration device, a nozzle, a nozzle cap, an electrode chuck, an electrolyte tank and a workbench. The present invention improves the localization, stability, precision and efficiency of micro-electrolysis processing.

Description

Technical Field

[0001] The present invention belongs to the field of ultrasonic energy field assisted electrolytic processing, and in particular relates to a processing method and device for ultrasonic coordinated air film shielding assisted micro-electrolysis. Background Art

[0002] Processing microstructures on the surface of certain parts can effectively improve their performance, so microstructures are widely used in aviation, aerospace, automobiles, electronics, molds and other industrial fields. Micro electrolytic machining is a representative technology for microstructure machining.

[0003] Micro-electrolytic machining is based on the principle of electrochemical anodic dissolution of metals. Micro-electrolytic machining uses tool electrodes with a diameter of tens to hundreds of microns, and usually performs electrochemical machining on the workpiece in a machining gap of tens of microns. Micro-electrolytic machining has the advantages of no loss of machining tools, the etching speed is not affected by the hardness and strength of the machining material, and the machining deformation is small. It has obvious advantages in the field of microstructure machining, and has therefore attracted extensive research in academia and industry at home and abroad. However, micro-electrolytic machining also has problems such as poor localization and stray corrosion during machining; although ultrashort pulse current micro-electrolytic machining can effectively improve machining localization, the machining efficiency is low; therefore, how to use micro-electrolytic machining technology to achieve stable, efficient and high-precision machining of workpieces is becoming more and more of a concern. Summary of the invention

[0004] In order to overcome the problems of poor localization and severe stray corrosion in the existing micro-electrolytic machining technology, the present invention provides a processing method and device for ultrasonic assisted air film shielding assisted micro-electrolysis, which improves the localization, stability, precision and efficiency of micro-electrolytic machining.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] A processing method of ultrasonic coordinated air film shielding assisted micro-electrolysis, the workpiece is tightly connected to the ultrasonic amplitude transformer of an ultrasonic vibration device, the workpiece is connected to the positive electrode of a power supply through the ultrasonic vibration device, the needle-shaped tool electrode used is clamped and fixed in the nozzle by an electrode chuck, the lower end of the electrode extends from the central liquid outlet of the nozzle, and the electrode is connected to the negative electrode of the power supply through the nozzle; a high-speed electrolyte enters the electrolyte cavity of the nozzle through the liquid inlet, and then passes through the liquid outlet at the lower end of the nozzle to coat the tool electrode and is sprayed to the surface of the workpiece at a high speed, participating in the electrochemical reaction between the tool electrode and the workpiece; at the same time, high-pressure gas The gas enters the gas cavity of the nozzle through the air inlet, and then is ejected through the annular air outlet around the liquid outlet at the lower end of the nozzle. When ejecting, the gas covers the electrolyte beam to form an air film, which constrains the diameter of the electrolyte beam. At the same time, the workpiece being processed generates vibrations of a certain frequency and amplitude under the action of ultrasonic vibration. During processing, the workpiece is fixed, and the machine tool drives the nozzle and the electrode to feed toward the workpiece, maintaining a certain processing gap between the workpiece and the electrode, and the high-speed electrolyte covered with the high-pressure air film is sprayed onto the workpiece under the action of ultrasound, thereby achieving stable and efficient processing and obtaining the required microstructure.

[0007] Furthermore, under the action of the ultrasonic energy field, the electrolyte pressure in the gap is relatively high (can reach tens of MPa), which limits the gas coated outside the electrolyte beam from entering the electrolyte beam. At the same time, the high gap pressure suppresses the growth of gap bubbles, allowing the electrolyte to maintain a high conductivity; on the other hand, ultrasonic vibration promotes the discharge of gap electrolysis products, thereby increasing the material removal rate.

[0008] A device for ultrasonic coordinated air film shielding assisted micro electrolytic machining, comprising an ultrasonic vibration device, a nozzle, a nozzle cap, an electrode chuck, an electrolyte tank and a workbench, wherein the nozzle and the nozzle cap are connected by threads, and the nozzle cap is connected to a machine tool by threads; an electrolyte chamber and a gas chamber are arranged in the nozzle, a liquid inlet connected thereto is arranged on the electrolyte chamber, an air inlet connected thereto is also arranged in the gas chamber, and an air compressor is externally connected to the gas compressor through an air supply pipe, and the nozzle gas chamber is located below the electrolyte chamber, during machining, the electrolyte flows out from a small hole at the lower end of the nozzle axis through the electrolyte chamber, and the gas is ejected from an annular air outlet at the lower end of the nozzle through the gas chamber;

[0009] The electrode chuck is inside the nozzle, and is fixed by contacting the nozzle cap with the upper end and the inner cavity of the nozzle with the lower end; the needle-shaped electrode is clamped by the electrode chuck, and the electrode passes through the cavity at the axis of the nozzle and protrudes out of the nozzle outlet;

[0010] The ultrasonic vibration device is placed vertically on the workbench, and the workpiece is fixed to the horn of the ultrasonic vibration device by threaded connection; the vibration parameters of the ultrasonic vibration device, such as amplitude and frequency, can be adjusted by an ultrasonic power supply and its controller, and the ultrasonic vibration device is fixed by bolting its flange to the recessed platform of the workbench;

[0011] The electrolyte tank is placed flat on the workbench, and a through hole is provided in the middle part of the bottom of the electrolyte tank, and the ultrasonic vibration device passes through the through hole. A sealing ring is provided at the connecting part between the electrolyte tank and the ultrasonic vibration device to prevent the electrolyte from penetrating into the transducer part of the ultrasonic vibration device; two through holes are symmetrically provided on both sides of the bottom of the electrolyte tank, and a circular tube groove is extended outward from each of the two through holes, and the two circular tubular grooves pass through the two through holes on the workbench respectively. During processing, the electrolyte flows into the electrolyte circulation box under the workbench through the circular tube grooves of the electrolyte tank; the workpiece used is located directly below the nozzle during processing and is connected to the positive electrode of the power supply through the ultrasonic vibration device, and the tool electrode used is connected to the negative electrode of the power supply through the nozzle.

[0012] Furthermore, the workpiece is directly connected to the amplitude transformer of the ultrasonic vibration device through a threaded connection, and the workpiece processing surface is parallel to the worktable surface.

[0013] Furthermore, the ultrasonic vibration device is below the nozzle and vertically fixed on the workbench, and the lower end portion of the ultrasonic vibration device passes through the through hole of the workbench.

[0014] Furthermore, the air inlet and the liquid inlet are both arranged horizontally, the liquid outlet and the tool electrode are both distributed vertically, the air outlet discharges air at a certain angle, and the tool electrode is coaxially arranged with the air outlet and the liquid outlet.

[0015] Furthermore, the tool electrode used is made of tungsten material and is in the shape of a needle, with a tip portion having a diameter of less than 100 microns.

[0016] The beneficial effects of the present invention are mainly manifested in:

[0017] 1. The present invention combines ultrasonic field with air film shielding processing, so that the air film shielding and ultrasonic assistance work together to cooperate with micro-electrolytic machining technology to process the metal surface, that is, while a layer of high-pressure gas is wrapped around the machining liquid beam, the workpiece is also acted upon by the ultrasonic vibration device. In this way, the air film shielding not only plays a limiting role in the spray range of the electrolyte beam, but also reduces the gas volume fraction of the electrolyte beam by utilizing the effect of the ultrasonic field, thus compensating for the shortcoming of the air film shielding electrolytic machining that the material removal rate is reduced due to the increase in the gas volume fraction in the electrolyte. Ultrasonic assistance and air film shielding work together to assist micro-electrolytic machining, which not only improves the machining localization, improves the stray corrosion phenomenon during the machining process, but also increases the material removal rate, thereby improving the machining accuracy and machining efficiency of micro-electrolytic machining within the micron scale range.

[0018] 2. The size and shape of the workpiece processed by the present invention are calculated through finite element simulation analysis and are directly connected to the amplitude rod of the ultrasonic vibration device, which makes the installation and disassembly of the workpiece convenient and avoids the problem of uncontrollable vibration frequency and amplitude caused by adding load to the ultrasonic vibration device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the general assembly drawing of the device.

[0020] Figure 2 This is an enlarged view of the nozzle outlet.

[0021] Figure 3 This is a diagram of the electrolyte tank structure.

[0022] Figure 4 This is a structural diagram of the coordination between the ultrasonic vibration device and the workbench. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings.

[0024] Reference Figure 1 to Figure 4 , an ultrasonic synergistic air film shielding assisted micro-electrolysis processing device, comprising an ultrasonic vibration device 9, a nozzle 3, a nozzle cap 2, a tool electrode chuck 6, an electrolyte tank 7 and a workbench 8, wherein the nozzle 3 is connected to the nozzle cap 2 by threads, and the nozzle cap 2 is connected to the machine tool spindle 1 by threads; the nozzle 3 has an electrolyte chamber 12 and a gas chamber 5, the electrolyte chamber 12 is provided with a liquid inlet 13 connected thereto, the gas chamber 5 is also provided with an air inlet 4 connected thereto, and an air compressor is externally connected through an air supply pipe, the nozzle gas chamber 5 is located below the electrolyte chamber 12, during processing, the electrolyte flows out from the small hole 17 at the lower end of the axis of the nozzle 3 through the electrolyte chamber 12, and the gas is ejected from the annular air outlet 15 at the lower end of the nozzle 3 through the gas chamber 5;

[0025] The tool electrode chuck 6 is inside the nozzle 3, and the tool electrode chuck 6 contacts the nozzle cap 2 through the upper end 14, and the lower end 19 contacts the inner cavity of the nozzle to achieve fixation; the needle-shaped tool electrode 16 is clamped by the tool electrode chuck 6, and the tool electrode 16 passes through the cavity 18 at the axis of the nozzle 3 and protrudes out of the nozzle liquid outlet 17;

[0026] The ultrasonic vibration device 9 is placed vertically on the workbench 8. The vibration parameters of the ultrasonic vibration device 9, such as amplitude and frequency, can be adjusted by an ultrasonic power supply and its controller. The ultrasonic vibration device 9 is fixed by bolting its flange 23 to the workbench recess 27.

[0027] The electrolyte tank 7 is placed flat on the workbench 8. A through hole 21 is provided in the middle part of the bottom of the electrolyte tank 7. The ultrasonic vibration device 9 passes through the through hole 21. A sealing ring 10 is provided at the connection part between the electrolyte tank 7 and the ultrasonic vibration device 9 to prevent the electrolyte from penetrating into the lower end of the ultrasonic vibration device 9. Two circular tube grooves 20 extending outward are symmetrically provided on both sides of the bottom of the electrolyte tank 7. The two circular tube grooves 20 pass through the two through holes 24 on the workbench respectively. During processing, the electrolyte flows into the electrolyte circulation box under the workbench 8 through the circular tube grooves 20 of the electrolyte tank. During processing, the workpiece 11 used is located below the nozzle 3 and is connected to the positive pole of the power supply through the ultrasonic vibration device 9. The tool electrode 16 used is connected to the negative pole of the power supply through the nozzle 3.

[0028] Furthermore, the workpiece 11 is connected to the horn 22 of the ultrasonic vibration device through a thread, and the workpiece processing surface is parallel to the worktable surface.

[0029] Furthermore, the ultrasonic vibration device 9 is below the nozzle 3 and vertically fixed on the workbench 8 , and the lower end portion of the ultrasonic vibration device 9 passes through the through hole 26 of the workbench.

[0030] Furthermore, the air inlet 4 and the liquid inlet 13 are arranged horizontally, the liquid outlet 17 and the tool electrode 16 are vertically divided, the air outlet 15 discharges air at a certain angle, and the tool electrode 16 is coaxially arranged with the air outlet 15 and the liquid outlet 17 .

[0031] Furthermore, the tool electrode 16 used is made of tungsten and is in a needle shape, with a tip portion having a diameter of less than 100 microns.

[0032] A processing method of ultrasonic coordinated air film shielding assisted micro-electrolysis, the workpiece 11 is tightly connected to the ultrasonic horn 22 of the ultrasonic vibration device through a threaded connection, the workpiece is connected to the positive electrode of the power supply through the ultrasonic vibration device 9, the needle-shaped tool electrode 16 used is clamped and fixed in the nozzle 3 by the tool electrode chuck 6, the lower end of the tool electrode 16 extends from the liquid outlet 17 of the nozzle 3, and the tool electrode 16 is connected to the negative electrode of the power supply through the nozzle 3; the high-speed electrolyte enters the electrolyte cavity 12 of the nozzle 3 through the liquid inlet 13, and then passes through the liquid outlet 17 at the lower end of the nozzle 3 to cover the tool electrode 16 and spray out at a high speed, participating in the electrochemical reaction between the tool electrode and the workpiece; At the same time, high-pressure gas enters the gas cavity 5 of the nozzle 3 through the air inlet 4, and then sprays out through the annular air outlet 15 around the liquid outlet 17 at the lower end of the nozzle 3. When spraying, the gas wraps around the electrolyte beam to form a gas film, which constrains the diameter of the electrolyte beam; at the same time, under the action of the ultrasonic vibration device 9, the workpiece 11 produces a vibration of a certain frequency and amplitude, accompanied by the impact of the high-speed electrolyte, the workpiece will produce micro-deformation, making the material removal more uniform, and at the same time, the ultrasonic action increases the pressure in the processing area, so that the gas outside the electrolyte beam cannot enter the electrolyte beam, reducing the gas volume fraction in the electrolyte beam, thereby increasing the material removal speed. During processing, the workpiece is fixed, and the machine tool drives the nozzle and the tool electrode to feed toward the workpiece, maintaining a certain processing gap between the workpiece and the tool electrode, and the high-speed electrolyte coated with the high-pressure gas film is sprayed onto the ultrasonic workpiece, achieving stable and efficient processing and obtaining the required microstructure.

Claims

1. A method for processing micro-electrolysis assisted by ultrasound and air film shielding, characterized in that: The processing device includes an ultrasonic vibration device, a nozzle, a nozzle cap, a tool electrode chuck, an electrolyte tank and a workbench, wherein the nozzle and the nozzle cap are connected by threads, and the nozzle cap is connected to the machine tool by threads; the nozzle has an electrolyte chamber and a gas chamber, the electrolyte chamber is provided with a liquid inlet connected thereto, the gas chamber is also provided with an air inlet connected thereto, and an air compressor is externally connected to the gas supply pipe, the nozzle gas chamber is located below the electrolyte chamber, during processing, the electrolyte flows out from the small hole at the lower end of the nozzle axis through the electrolyte chamber, and the gas is ejected from the annular air outlet at the lower end of the nozzle through the gas chamber; The tool electrode chuck is inside the nozzle, and is fixed by contacting the nozzle cap with the upper end and the inner cavity of the nozzle with the lower end; the needle-shaped tool electrode is clamped by the tool electrode chuck, and the tool electrode passes through the cavity at the axis of the nozzle and protrudes out of the nozzle liquid outlet; The ultrasonic vibration device is placed vertically on the workbench, and the workpiece is fixed to the horn of the ultrasonic vibration device by threaded connection; the vibration parameters of the ultrasonic vibration device, such as amplitude and frequency, are adjusted by an ultrasonic power supply and its controller, and the ultrasonic vibration device is fixed by bolting its flange to the recessed platform of the workbench; The electrolyte tank is placed flat on the workbench, and a through hole is provided in the middle part of the bottom of the electrolyte tank, and the ultrasonic vibration device passes through the through hole. A sealing ring is provided at the connection part between the electrolyte tank and the ultrasonic vibration device to prevent the electrolyte from penetrating into the transducer part of the ultrasonic vibration device; two through holes are symmetrically provided on both sides of the bottom of the electrolyte tank, and a circular tube groove is extended outward from each of the two through holes, and the two circular tubular grooves pass through the two through holes on the workbench respectively. During processing, the electrolyte flows into the electrolyte circulation box under the workbench through the circular tube grooves of the electrolyte tank. During processing, the workpiece used is located below the nozzle and is connected to the positive pole of the power supply through the ultrasonic vibration device, and the tool electrode used is connected to the negative pole of the power supply through the nozzle; the workpiece is tightly connected to the ultrasonic amplitude transformer of the ultrasonic vibration device, and the workpiece is connected to the positive pole of the power supply through the ultrasonic vibration device. The needle-shaped tool electrode used is connected by the work The tool electrode chuck is clamped and fixed in the nozzle, the lower end of the tool electrode extends from the liquid outlet of the nozzle, and the tool electrode is connected to the negative pole of the power supply through the nozzle; the high-speed electrolyte enters the electrolyte cavity of the nozzle through the liquid inlet, and then is sprayed out to the surface of the workpiece at a high speed through the liquid outlet at the lower end of the nozzle, covering the tool electrode, and participating in the electrochemical reaction between the tool electrode and the workpiece; at the same time, high-pressure gas enters the gas cavity of the nozzle through the air inlet, and then is sprayed out through the annular air outlet around the liquid outlet at the lower end of the nozzle. When spraying, the gas covers the electrolyte beam to form a layer of air film, which constrains the electrolyte beam and the electrolyte diameter; during processing, the workpiece is fixed, and the machine tool drives the nozzle and the tool electrode to feed toward the workpiece, maintaining a certain processing gap between the workpiece and the tool electrode, and the high-speed electrolyte coated with the high-pressure air film is sprayed onto the workpiece under ultrasonic action, so as to achieve stable and efficient processing and obtain the required microstructure.

2. The ultrasonic assisted air film shielding assisted micro electrolysis processing method according to claim 1, characterized in that: Under the action of ultrasonic vibration, the processed workpiece produces vibrations of a certain frequency and amplitude. Under the action of the ultrasonic energy field, the electrolyte pressure in the gap is relatively large, which limits the gas coated outside the electrolyte beam from entering the electrolyte beam. At the same time, the high gap pressure suppresses the growth of gap bubbles, allowing the electrolyte to maintain a high conductivity. On the other hand, ultrasonic vibration promotes the discharge of gap electrolysis products, thereby increasing the material removal rate.

3. The ultrasonic assisted air film shielding assisted micro electrolysis processing method according to claim 1, characterized in that: The workpiece used is directly connected to the amplitude changing rod of the ultrasonic vibration device through a threaded connection, and the processing surface of the workpiece is parallel to the working table surface.

4. The ultrasonic assisted air film shielding assisted micro electrolysis processing method according to claim 1 or 3, characterized in that: The ultrasonic vibration device is below the nozzle and vertically fixed on the workbench, and the lower end portion of the ultrasonic vibration device passes through the through hole of the workbench.

5. The ultrasonic assisted air film shielding assisted micro electrolysis processing method according to claim 1 or 3, characterized in that: The air inlet and the liquid inlet are both arranged horizontally, the liquid outlet and the tool electrode are both vertically divided, the air outlet discharges air at a certain angle, and the tool electrode is coaxially arranged with the air outlet and the liquid outlet.

6. The ultrasonic assisted air film shielding assisted micro electrolysis processing method according to claim 1 or 3, characterized in that: The tool electrode used is made of tungsten and is needle-shaped, with a tip diameter of less than 100 microns.

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