A method and system for coaxial coupling of tube jet laser and electrochemical discharge processing

Abstract

This invention belongs to the field of composite machining, specifically providing a coaxial coupling machining method and system for tube-jet laser-electrochemical discharge. This technology employs a coaxial structure design, coupling laser, electrochemical discharge, electrochemical, and mechanical grinding technologies. It utilizes a double-layer tube electrode design: an outer conductive layer with abrasive particles and an inner total reflection layer that focuses the laser beam onto the center of the tube electrode's inner hole. The central laser beam serves as the primary energy source, leveraging its high energy density to achieve rapid material ablation and removal, significantly improving the overall efficiency of micro-hole machining. Electrochemical discharge and grinding ensure the shape accuracy and diameter consistency of the machined hole. Simultaneously, the electrochemical reaction and grinding effectively improve the surface finish of the workpiece's machined area. This invention, through its coaxial coupling machining mechanism, simultaneously achieves high machining efficiency, excellent surface quality, and high-precision geometric morphology, making it suitable for the machining requirements of ultra-high precision micro-holes in ceramic / metal multilayer composite materials.

Description

Technical Field

[0001] This invention belongs to the field of special processing technology, and more specifically, relates to a tube jet-electrochemical discharge coaxial coupling processing method and system. Background Technology

[0002] With the rapid iteration and upgrading of modern high-tech industries, various products are developing towards miniaturization and refinement. Micro-hole functional structures have now been widely used in many high-end manufacturing fields such as aerospace, biomedicine, chip packaging, and optical devices. These micro-hole structures in industrial scenarios place extremely stringent technical requirements on processing techniques. To overcome the technical bottlenecks in high-quality micro-hole processing of brittle and hard materials, researchers both domestically and internationally have conducted extensive targeted explorations and research, successively proposing and developing a variety of dedicated micro-hole processing methods.

[0003] Among various micro-hole machining technologies, electrochemical discharge machining (EDM) combines the dual effects of electrochemistry and electrical discharge. It continuously generates gas through an electrochemical reaction at the electrode-electrolyte interface. This gas accumulates on the electrode surface, forming a dense and stable gas film that effectively isolates the electrode from direct contact with air and electrolyte. Subsequently, under the influence of an external electric field, the gas film is broken down, generating a pulsed discharge. The localized high-temperature energy released during the discharge process is used to melt, etch, and shape brittle and hard materials such as glass, ceramics, and metals. This machining method achieves excellent surface finish, but its overall processing efficiency is relatively low.

[0004] Laser processing is another widely used non-contact micro-hole processing technology. This technology relies on the interaction between a high-energy-density laser beam and the material, utilizing the thermal effect of the laser to rapidly melt, vaporize, and remove brittle and hard materials. It is currently a relatively efficient method for micro-hole processing. However, due to factors such as laser beam diffraction and spot diameter, the dimensional accuracy and hole diameter consistency of the processed material are difficult to achieve ultra-high precision requirements. Furthermore, laser processing has a large heat-affected zone, which can easily lead to problems such as material remelting, micro-cracks, and high hole wall roughness due to localized high temperatures, resulting in poor surface finish. Summary of the Invention

[0005] The purpose of this invention is to provide a coaxial coupling processing method and system for tube jet laser-electrochemical discharge, which solves the technical problem of difficulty in balancing efficiency, shape accuracy and surface quality in the processing of micro-holes in brittle and hard materials by synergistic integration and complementary adaptation of the technical advantages of laser processing, electrochemical discharge processing and mechanical grinding.

[0006] A method for coaxial coupling processing of tube jet laser and electrochemical discharge includes the following steps:

[0007] S1. Install the tube electrode below the pre-filled liquid container, place the workpiece to be processed in the electrolyte tank, inject electrolyte into the electrolyte tank until the workpiece is completely submerged, connect the liquid supply pump and the pre-filled liquid container to form an electrolyte flow path, and the connection part of the flushing device and the tube electrode is located below the laser focusing lens.

[0008] S2. Start the liquid supply pump and wait for the electrolyte to completely fill the pre-filled liquid container;

[0009] S3. Start the laser generator, adjust the focal length of the laser focusing lens to accurately focus the laser beam on the center of the inner hole of the tube electrode, and guide it to the workpiece surface through the electrolyte jet.

[0010] S4. When the pulse power supply is turned on, the tube electrode discharges under the pulse voltage output by the pulse power supply, which works in conjunction with the laser to remove the workpiece material.

[0011] S5. Start the motor, set the speed, and control the tube electrode to start rotating;

[0012] S6. Start the control system and perform processing according to the preset processing program.

[0013] Furthermore, in S1, the workpiece type mainly includes ceramic / metal multilayer composite materials, such as high-temperature nickel-based alloys with ceramic coatings, which can achieve high-precision processing of various materials without replacing the core processing components.

[0014] Furthermore, in S3, the laser focusing lens and the tube electrode are arranged coaxially to ensure that the laser beam propagates along the center line of the electrode and is finally focused on the workpiece processing surface, and the laser focusing area coincides with or is adjacent to the electrochemical discharge area.

[0015] Furthermore, in step S4, under the action of the pulse voltage output by the pulse power supply, the tube electrode undergoes an electrolytic reaction with the surrounding electrolyte to continuously generate gas. As the electrolytic reaction proceeds, tiny bubbles continuously gather and merge, forming a dense gas film on the surface of the tube electrode, effectively blocking direct contact between the tube electrode surface and the electrolyte. When the pulse voltage rises to the gas film breakdown threshold, the gas film is instantly broken down to form a stable discharge channel. The high temperature generated by the discharge forms an annular heat source, which works synergistically with the central heat source formed by the laser to achieve the removal of workpiece material.

[0016] Furthermore, the processing involves the combined effects of laser, electrochemical discharge, electrochemical reaction, and mechanical grinding. Compared to a single processing method, laser action can significantly improve processing efficiency, electrochemical discharge and mechanical grinding can ensure the shape accuracy of the processed hole, and electrochemical reaction and mechanical grinding can effectively improve the surface quality of the workpiece.

[0017] A coaxial coupling machining system for tube jet laser-electrochemical discharge, used to implement the above method, includes the following core components: laser generator; liquid supply pump; pulse power supply; laser guide; electrolyte filtration device; focusing lens; pre-filled liquid container; transmission device; motor; turbulence device; electrolyte tank; workpiece fixing device; workpiece pad; tube electrode; and control system.

[0018] Furthermore, the electrolyte supply pump can continuously and stably supply electrolyte to the processing area through the tube electrode, and can precisely control the jet pressure to ensure that the electrolyte flows into the processing gap evenly at the set pressure, and can quickly discharge the reaction products and debris generated during processing.

[0019] Furthermore, the tube electrode adopts a double-layer composite structure design, including an outer conductive layer and an inner total reflection layer. The conductive layer is inlaid with spirally arranged abrasive grains. The conductive layer functions to cooperate with the electrolyte, auxiliary electrode, or workpiece to achieve stable electrochemical discharge, and can also perform grinding on the hole wall under the drive of motor rotation. The refractive index of the total reflection layer and the electrolyte for the laser output is significantly different, and the incident angle of the laser at the interface between the total reflection layer and the electrolyte is strictly greater than the critical angle of the interface. This achieves stable internal total reflection propagation of the laser in the inner hole of the tube electrode, forming a stable optical path for the laser in the inner hole of the tube electrode, avoiding laser scattering or energy loss in the electrolyte, and ensuring efficient transmission of laser energy to the processing area.

[0020] Furthermore, the laser guide is composed of optical components such as a reflector, a beam collimator, and a focusing lens, and has high-precision beam guiding and focusing adjustment functions. It can collimate and shape the laser beam generated by the laser and accurately guide it to the inner hole of the tube electrode to ensure that the laser beam is efficiently transmitted into the processing area.

[0021] Furthermore, the tube electrode is connected to the negative terminal of the pulse power supply; when processing ceramic / metal multilayer composite materials, an auxiliary electrode connected to the positive terminal of the pulse power supply can be placed in the electrolyte to form a path with the tube electrode, or the positive terminal of the pulse power supply can be connected to the workpiece to form a path. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the processing device in an example of the present invention.

[0023] Figure 2 , 3 This is a schematic diagram illustrating the processing principle in an example of the present invention.

[0024] Figure label:

[0025] 1. Laser generator; 2. Liquid supply pump; 3. Pulse power supply; 4. Laser guide; 5. Electrolyte filtration device; 6. Focusing lens; 7. Pre-filled container; 8. Transmission device; 9. Motor; 10. Turbulence device; 11. Electrolyte tank; 12. Electrolyte; 13. Workpiece fixing device; 14. Workpiece pad; 15. Workpiece; 16. Tube electrode; 17. Auxiliary electrode; 18. Control system. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] A method for coaxial coupling processing of tube jet laser and electrochemical discharge includes the following steps:

[0028] S1. Install the tube electrode 16 below the pre-filled liquid container 7, connect the tube electrode 16 to the motor 9 through the transmission device, fix the workpiece 15 (nickel-based high-temperature alloy with ceramic coating) to be processed in the electrolyte tank 11, inject electrolyte 12 into the electrolyte tank 11 until the workpiece is completely submerged and the liquid level is 0.5-2mm above the workpiece surface, connect the liquid supply pump 2 to the pre-filled liquid container 7 to form an electrolyte flow path, and the connection part between the pre-filled liquid container 7 and the tube electrode 16 is located below the laser focusing lens 6;

[0029] S2. Start the electrolyte supply pump 2, set the flushing pressure to 0.5 MPa, and wait until the electrolyte completely fills the pre-filled container 7 and can stably flow out from the inner hole of the tube electrode 16. The electrolyte is a 6 mol / L NaOH solution;

[0030] S3. Start the laser generator 1, set the average power range of the laser to 0~30W, wavelength 532nm, adjust the focal length of the laser focusing lens so that the laser beam is precisely focused on the center of the inner hole of the tube electrode 16, and guided by the electrolyte jet to act on the processing surface of the workpiece 15.

[0031] S4. Turn on the pulse power supply 3, set the voltage range to 30-40V, the duty cycle to 50%, and the pulse frequency to 500Hz. The tube electrode generates a discharge phenomenon under the action of the pulse voltage output by the pulse power supply, which works in conjunction with the laser to remove the workpiece material.

[0032] S5. Start motor 9, set the speed, the speed adjustment range is 0~24000r / min, and control tube electrode 16 starts to rotate;

[0033] S5. Start the control system 20 and perform processing according to the preset processing program.

[0034] Reference Figure 1 As shown, this invention provides a tube jet laser-electrochemical discharge coaxial coupling processing system for implementing the above-mentioned processing method, comprising the following components: laser generator 1; liquid supply pump 2; pulse power supply 3; laser guide 4; electrolyte filter device 5; focusing lens 6; pre-filled liquid container 7; transmission device 8; motor 9; turbulence device 10; electrolyte tank 11; electrolyte 12; workpiece fixing device 13; workpiece pad 14; workpiece 15; tube electrode 16; auxiliary electrode 17; and control system 18.

[0035] In this example, the pre-filled liquid container 7 is connected to the filter device 5. The electrolyte pumped out from the supply pump 2 first passes through the filter device 5 to remove impurities before flowing into the pre-filled liquid container.

[0036] In this example, the laser guide 4 is composed of optical elements such as a reflector, a beam collimator, and a focusing lens 6. It is connected to the laser generator 1 through a glass optical fiber and is located above the pre-filled liquid container 7. The laser can enter the inner hole of the tube electrode 14 through the focusing lens 6.

[0037] In this example, the current stabilizing device 8 is installed at the inlet of the tube electrode 16. The electrolyte 10 enters the tube electrode 14 through the current stabilizing device, which can ensure that the electrolyte is in a laminar flow state inside the tube.

[0038] In this example, the tube electrode 16 adopts a double-layer structure design, including an outer conductive layer and an inner total reflection layer. The outer surface is inlaid with diamond abrasive grains with a mesh size of 400.

[0039] In this example, the motor 9 is connected to the tube electrode 16 via a transmission device, which can drive the tube electrode to rotate at a set speed.

[0040] In this example, the tube electrode 16 is connected to the negative terminal of the pulse power supply 3. During processing, the workpiece material is a ceramic / metal multilayer composite material. The positive terminal of the power supply can be connected to the conductive part of the workpiece, or an auxiliary electrode 17 connected to the positive terminal of the pulse power supply can be placed in the electrolyte to form a circuit with the tube electrode 16.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of the present invention, and these improvements should also be considered within the scope of protection of the present invention.

Claims

1. A method for coaxial coupling processing of tube jet laser and electrochemical discharge, characterized in that, Includes the following steps: S1. Install the tube electrode below the pre-filled liquid container (7), place the workpiece (15) to be processed in the electrolyte tank (9), inject electrolyte (10) into the electrolyte tank (9) until the workpiece (15) is completely submerged, connect the liquid supply pump (2) and the pre-filled liquid container (7) to form an electrolyte flow path, and the connection part of the flushing device and the tube electrode (16) is located below the laser focusing lens (6); S2. Start the liquid supply pump (2) and wait for the electrolyte (10) to completely fill the pre-filled liquid container (7). S3. Start the laser generator (1), adjust the focal length of the laser focusing lens (6) so that the laser beam is precisely focused on the center of the inner hole of the tube electrode (16) and guided by the electrolyte jet to the workpiece (15) processing surface. S4. When the pulse power supply (3) is turned on, the tube electrode (16) generates a discharge phenomenon under the action of the pulse voltage output by the pulse power supply, which works in conjunction with the laser to achieve the removal of the workpiece material. S5. Start the motor (9), set the speed, and control the tube electrode (16) to start rotating; S6. Start the control system (20) and perform processing according to the preset processing program.

2. The tube jet laser-electrochemical discharge coaxial coupling processing method as described in claim 1, characterized in that: In S1, the workpiece type mainly includes ceramic / metal multilayer composite materials, such as high-temperature nickel-based alloys with ceramic coatings, which can achieve high-precision machining of various materials without replacing the core processing components.

3. The tube jet laser-electrochemical discharge coaxial coupling processing method as described in claim 1, characterized in that: In S3, the laser focusing lens (6) and the tube electrode (16) are arranged coaxially to ensure that the laser beam propagates along the center line of the electrode and is finally focused on the workpiece (15) processing surface, and the laser focusing area coincides with or is adjacent to the electrochemical discharge area.

4. The tube jet laser-electrochemical discharge coaxial coupling processing method as described in claim 1, characterized in that: In S4, the tube electrode (16) reacts with the surrounding electrolyte under the action of the pulse voltage output by the pulse power supply (3) to continuously generate gas. As the electrolysis reaction proceeds, tiny bubbles continuously gather and merge, forming a dense gas film on the surface of the tube electrode (16), effectively blocking the direct contact between the surface of the tube electrode (16) and the electrolyte (10). When the pulse voltage rises to the gas film breakdown threshold, the gas film is instantly broken down to form a stable discharge channel. The high temperature generated by the discharge forms a ring heat source. This ring heat source works in synergy with the central heat source formed by the laser to remove the workpiece material.

5. The coaxial coupling processing method of tube jet laser-electrochemical discharge as described in claim 1, characterized in that: During the processing, the laser, electrochemical discharge, electrochemical reaction and mechanical grinding work together. Compared with a single processing method, the laser can significantly improve the processing efficiency, the electrochemical discharge and mechanical grinding can ensure the shape accuracy of the processed hole, and the electrochemical reaction and mechanical grinding can effectively improve the surface quality of the workpiece.

6. A tube jet laser-electrochemical discharge coaxial coupling processing system for implementing the method as described in claim 1, comprising the following core components: laser generator (1); liquid supply pump (2); pulse power supply (3); laser guide (4); electrolyte filter device (5); focusing lens (6); pre-filled liquid container (7); transmission device (8); motor (9); turbulence device (10); electrolyte tank (11); workpiece fixing device (13); workpiece pad (14); tube electrode (16); control system (18).

7. The tube-jet laser-electrochemical discharge coaxial coupling processing system as described in claim 6, characterized in that: The liquid supply pump (2) can continuously and stably supply electrolyte (10) to the processing area through the tube electrode (16), and can precisely control the jet pressure to ensure that the electrolyte flows into the processing gap at a set pressure and can quickly discharge the reaction products and debris generated during processing.

8. The tube-jet laser-electrochemical discharge coaxial coupling processing system as described in claim 6, characterized in that: The tube electrode (16) adopts a double-layer composite structure design, including an outer conductive layer and an inner total reflection layer. The conductive layer is inlaid with spirally arranged abrasive grains. The conductive layer functions to cooperate with the electrolyte (10), auxiliary electrode (18) or workpiece (15) to achieve stable electrochemical discharge, and can grind the hole wall under the drive of the motor (9) rotation. The total reflection layer and the electrolyte (10) have a significant difference in refractive index for the laser output of the laser. The incident angle of the laser at the interface between the total reflection layer and the electrolyte is strictly greater than the critical angle of the interface, thereby realizing stable internal total reflection transmission of the laser in the inner hole of the tube electrode (16), so that the laser forms a stable optical path in the inner hole of the tube electrode (16), avoiding scattering or energy loss of the laser in the electrolyte, and ensuring efficient transmission of laser energy to the processing area.

9. The tube-jet laser-electrochemical discharge coaxial coupling processing system as described in claim 6, characterized in that: The laser guide (4) is composed of optical components such as a reflector, a beam collimator, and a focusing lens (6). It has high-precision beam guiding and focusing adjustment functions, and can collimate and shape the laser beam generated by the laser and accurately guide it to the inner hole of the tube electrode (16) to ensure that the laser beam is efficiently transmitted into the processing area.

10. The tube-jet laser-electrochemical discharge coaxial coupling processing system as described in claim 6, characterized in that: The tube electrode (16) is connected to the negative terminal of the pulse power supply (3). When processing ceramic / metal multilayer composite materials, an auxiliary electrode (17) connected to the positive terminal of the pulse power supply can be placed in the electrolyte to form a path with the tube electrode, or the positive terminal of the pulse power supply can be connected to the workpiece (15) to form a path.

Images