Electrochemical gradient thickening-excitation micro-motion composite shape-preserving polishing ultra-precision manufacturing method and device

Abstract

According to the electrochemical gradient thickening-excitation micro-motion composite shape-preserving polishing ultra-precision manufacturing method, an electrochemical gradient thickening phase is used for inducing an electrochemical interface reaction to guide charged particles to move directionally and control the particle aggregation effect of suspension liquid, and then a flexible fluid grinding tool is used for generating excitation micro-power perpendicular to the axis for efficient shape-preserving removal. The invention further provides an electrochemical gradient thickening-excitation micro-motion composite shape-preserving polishing ultra-precision manufacturing device. The electrochemical gradient thickening-excitation micro-motion composite shape-preserving polishing ultra-precision manufacturing device comprises a box body, a shape-following polishing device, a power supply auxiliary device, an electrochemical gradient thickening polishing machining suspension liquid conveying device and a polishing auxiliary device. According to the method, the types of machined workpieces are rich, the profile precision can be greatly improved, and the near-atomic scale polishing precision of atoms can be achieved.

Description

Technical Field

[0001] The invention belongs to the field of ultra-precision grinding and polishing, and specifically relates to an ultra-precision manufacturing method and device for electrochemical gradient thickening-excitation micro-motion composite conformal polishing. Background Art

[0002] A microstructured surface is a tiny structured surface that has a regular periodic arrangement and can perform a variety of special functions such as optics, physics and biology. In recent years, due to the rapid progress of industries such as optical fiber communication and imaging technology, micro-components with microstructured optical functional surfaces (also called microstructured optical functional elements) have been widely used in micro optoelectronic and communication products, biomedicine, aerospace and intelligent guidance systems due to their small size, light weight and high integration. For example, the surface roughness of single crystal silicon or silicon carbide spherical / aspherical lens substrates, display backlight modules, and micro-prism structures of infrared reflection systems of aircraft and satellites, which are commonly used in infrared optical systems, must reach the nanometer level. However, due to its tiny structural size, low stiffness and high requirements for precision, traditional polishing technology often faces some limitations. In the past few years, many scholars have continued to explore ultra-precision polishing methods suitable for microstructured surfaces. In order to further optimize the manufacturing efficiency of microstructure array elements and solve the problem of uniform processing of microstructure micro-groove surfaces by abrasive flow during traditional abrasive jet polishing, the present invention proposes an electrochemical gradient thickening-excitation micro-motion composite conformal ultra-precision manufacturing method and device.

[0003] Electrochemical polishing technology is a surface treatment method that dissolves the anode of a metal workpiece in a specific electrochemical polishing liquid environment to reduce its surface roughness, improve brightness and give it a metallic luster. As a means of metal surface treatment, electrochemical polishing has the following advantages: 1) It can effectively reduce surface roughness, thereby achieving excellent surface polishing effect; 2) The polishing efficiency is very high and has no direct relationship with the mechanical properties of the treated material (such as hardness, toughness, strength, etc.); 3) Compared with mechanical polishing equipment, the equipment required for polishing formed parts is simpler and more economical. During the polishing process, the workpiece will not come into contact with the tool (cathode), and there will be no cutting force, heat, burrs or tool marks.

[0004] Maintaining the rotational stability of impeller blades, rotors, bearings, etc. is a major problem. Because rotating parts are prone to vortexing due to the system's own structure or severe external interference, the service life is reduced or the structure itself is damaged. However, the present invention uses this characteristic to realize microstructure nano-polishing technology, using the excitation micro-force perpendicular to the axis on the smooth rotor mechanism to induce the rotor to form vortex behavior, thereby achieving efficient conformal removal of materials and regulating the polishing surface accuracy.

[0005] The Chinese invention patent (CN117718551A) has been published, a multi-degree-of-freedom ultrasonic electrochemical assisted polishing equipment and processing method for complex curved surface parts, including a bed and a five-axis linkage system installed in the bed, a spindle system, a measuring system, a chain tool magazine, a numerical control system, and a polishing liquid circulation system. The tool, the workpiece to be processed, and the polishing liquid form a closed loop to form an electrochemical system; during the processing, the ultrasonic transducer is turned on, and the polishing liquid circulation system sprays the polishing liquid to the processing part. The workpiece to be processed loses electrons as an anode. Under the coupling effect of ultrasonic-electrochemical-mechanical grinding and polishing, the surface material of the workpiece to be processed is removed, and the ultrasonic electrochemical assisted polishing of complex curved surface parts is realized, and a workpiece with good surface quality and low surface roughness is obtained. The present invention is fully automatic processing, and the tool path is controlled by the numerical control system. Compared with traditional mechanical grinding and polishing, the surface roughness and shape accuracy of the processed parts are significantly improved. However, this patent does not involve the recovery and utilization of electrochemical polishing liquid.

[0006] The Chinese invention patent (CN117584024A) has been published, ultrasonic vibration and electrochemical assisted liquid film shearing high-efficiency polishing device and method; the polishing device includes a polishing tank for containing polishing liquid; the bottom of the polishing tank is provided with a polishing disc, and the polishing disc is arranged on the polishing disc driving spindle; the interior of the polishing tank, located below the polishing disc, is provided with an ultrasonic generator; the top of the polishing tank is provided with a workpiece clamping drive mechanism for clamping the workpiece and driving the workpiece to rotate; the workpiece clamping drive mechanism is connected to the adjustment mechanism and can move up and down under the drive of the adjustment mechanism; the polishing tank is connected to the negative pole of the pulse power supply, and the workpiece clamping drive mechanism is connected to the positive pole of the pulse power supply, and a closed loop is formed in combination with the polishing liquid in the polishing tank during polishing. The polishing device of the present invention combines the three technologies of ultrasonic vibration, electrochemical anodizing, and liquid film shearing polishing to polish the workpiece, thereby improving the material removal efficiency and processing uniformity of the workpiece. However, this patent cannot polish tiny structural parts, and it is expected to further improve the expansion of part types and performance.

[0007] A Chinese invention patent (CN115401534B) has been disclosed, a method for conformal polishing of a microarray mold, which is achieved by making a profiling polishing tool head that matches the surface shape of the microarray mold, adding abrasives between the profiling polishing tool head and the microarray mold, and realizing micro-vibration of the microarray mold or the profiling polishing tool head at a certain frequency and amplitude through an XY two-dimensional electric shift stage. The abrasive between the profiling polishing tool head and the microarray mold produces a micro-cutting action to remove material under the relative pressure and relative movement of the two, thereby removing defects such as knife marks and scratches on the surface of the micro mold. This method can get rid of the limitation of the extremely small size of the characteristic points of the microarray mold, and polish all the characteristic points on the microarray mold at the same time, with high efficiency, and will not damage the surface shape accuracy of the microarray mold, and can achieve higher surface shape accuracy and surface quality. However, this patent does not involve electrochemical polishing, and there is still room for improvement in the efficient grinding and polishing of workpieces. Summary of the invention

[0008] In order to overcome the shortcomings of the existing technology and solve the problem that tiny structural parts are difficult to maintain their shape, the present invention provides an electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method and device, which can not only greatly improve the surface accuracy, but also achieve atomic and near-atomic scale polishing accuracy.

[0009] The technical solution adopted by the present invention to solve its technical problem is:

[0010] An ultra-precision manufacturing method for electrochemical gradient thickening-excitation micro-motion composite conformal polishing utilizes an electrochemical gradient thickening phase to induce an electrochemical interface reaction to guide the directional motion of charged particles and control the particle aggregation effect of the suspension, and then utilizes a flexible fluid abrasive tool to generate excitation micro-motion perpendicular to the axis for efficient conformal removal.

[0011] Furthermore, the electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method comprises the following steps:

[0012] (1) placing the anode workpiece on a polishing workbench, connecting the anode clamp to the anode workpiece, and connecting the cathode clamp to the flexible conformable member;

[0013] (2) Turn on the numerical control device to control the path and process index of the flexible conformable component so that the starting point fits on the anode workpiece;

[0014] (3) adding an electrochemical gradient thickened polishing suspension containing nano-abrasive particles into a storage box, turning on a hydraulic pump, and allowing the electrochemical gradient thickened polishing suspension to flow into a conformal polishing device along a liquid infusion tube;

[0015] (4) Turn on the circuit controller and the electrochemical thickening generator, the electrochemical gradient thickening phase induces the electrochemical interface reaction to guide the directional movement of the charged particles and control the particle aggregation effect of the suspension, and the flexible conformal component flow weakens the rigidity rheology in time to form a flexible "fluid mold";

[0016] (5) The spindle box is turned on, and the rotating flexible "fluid mold" generates an exciting micro-force perpendicular to the axis. The exciting micro-force induces the flexible "fluid mold" to form a vortex behavior, resulting in the dynamic mechanism of the exciting micro-motion polishing liquid regulation, which promotes the micro-vibration of the flexible fluid to facilitate the residence and dynamic trajectory behavior of the micro-abrasive flexible "fluid mold". In the area of ​​composite action of exciting micro-motion, efficient conformal removal of materials and regulation of polishing surface accuracy are achieved.

[0017] Furthermore, in (1), a rotor is arranged in the inner cavity of the flexible conformable component, and a stator is arranged at an eccentric position of the outer cavity to maintain a certain airtightness; the flexible conformable component is deformed according to the shape of the target anode workpiece so as to be highly fitted to the surface of the anode workpiece; when the flexible conformable component rotates with the rotating shaft, the flexible conformable component generates an exciting micro-force perpendicular to the axis, and the exciting micro-force induces the flexible conformable component to form a vortex behavior, thereby efficiently removing materials in a conformal manner.

[0018] Furthermore, in (4), the electrochemical gradient thickening phase is porous microsphere particles. When the porous microsphere particles are integrated into the electrochemical gradient thickening polishing suspension, a slow chemical reaction occurs to generate negatively charged particles. At this time, the negatively charged particles induce the positively charged metal nanoabrasives to produce a clustering effect.

[0019] Preferably, the electrochemical gradient thickening or gradient dilution is achieved by the relative quantity ratio of the electrochemical gradient thickening phase and the electrochemical gradient thickening polishing suspension.

[0020] The electrochemical gradient thickening phase is carboxylate, carbonate, sulfite or amino acid salt.

[0021] In (3), the nano-abrasive particles include one or a mixture of two or more of nano-diamond, cubic boron oxide, boron carbide, silicon carbide, silicon nitride, silicon oxide, gallium oxide, iron oxide, magnesium oxide, lithium fluoride, graphite or Al2O3.

[0022] In said (3), the electrochemical gradient thickened polishing processing suspension includes acidic, neutral or alkaline polishing liquid; for processing silicon-based materials or alloy materials, an acidic electrochemical polishing liquid is used, including phosphoric acid, sulfuric acid, perchloric acid, phosphoric acid-sulfuric acid and electrochemical polishing liquids with various additives; electrochemical thickening incorporates slow-release physical and chemical particles, i.e., liquid flow property regulating particles, to regulate the affinity and repellency characteristics of the liquid flow contact structure surface.

[0023] The sustained-release chemical particles are sodium polyacrylate, polyvinyl alcohol or polyurethane thickeners.

[0024] An electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing device, comprising a box, a conformal polishing device, a power supply auxiliary device, an electrochemical gradient thickening polishing suspension conveying device and a polishing auxiliary device, wherein the conformal polishing device is located at the middle end of the box; the power supply auxiliary device is located at the left end of the box; the electrochemical gradient thickening polishing suspension conveying device is located at the right end of the box; and the polishing auxiliary device is located inside the box;

[0025] The conformable polishing device comprises, from top to bottom, a spindle box, a spindle, an electrochemical gradient thickening polishing suspension flow channel, a current delivery channel, an electrochemical thickening generator, a connecting shaft, a rotating shaft, a flexible conformable component and a detector. The upper end of the spindle is connected to the spindle box, the lower end of the spindle is connected to the electrochemical thickening generator, an electrochemical gradient thickening polishing suspension flow channel and a current delivery channel are opened at the spindle, the connecting shaft connects the electrochemical thickening generator and the rotating shaft, and the flexible conformable component and the detector are installed at the rotating shaft.

[0026] Furthermore, a rotor is arranged in the inner cavity of the flexible conformable component, and a stator is arranged at an eccentric position of the outer cavity, thereby maintaining a certain air tightness.

[0027] The power supply auxiliary device includes a high-voltage power supply, an anode clamp, a cathode clamp, a circuit protection device, a transformer and a circuit controller. The anode of the power supply is connected to the anode workpiece through the circuit protection device, the cathode of the power supply is connected to the flexible conformal component through the transformer, and the circuit controller is responsible for controlling the circuit power supply and current.

[0028] The electrochemical gradient thickening polishing suspension liquid conveying device includes an infusion tube, a hydraulic pump, a storage box and a recovery tank. The electrochemical gradient thickening polishing suspension liquid flows through the infusion tube in sequence through the hydraulic pump and the conformal polishing device to reach the inner cavity of the flexible conformal component, and then flows into the recovery tank through the through hole of the polishing workbench, completing the electrochemical polishing liquid conveying and recovery.

[0029] The polishing auxiliary device includes a numerical control device, a landing gear, a mobile frame, a slide, an x-axis guide rail, a y-axis guide rail, a z-axis guide rail, an anode workpiece, a fixture and a polishing workbench. The landing gear, the mobile frame and the slide are respectively connected to each other through the x-axis guide rail, the y-axis guide rail or the z-axis guide rail. The numerical control device controls their movement. The z-axis guide rail on the slide is connected to the conformal polishing device. The lower end of the conformal polishing device is a polishing workbench. A fixture is installed on the polishing workbench, and an anode tool is installed on the fixture.

[0030] The electrochemical thickening generator can realize a controllable gradient change in the viscosity of the electrochemical gradient thickening polishing suspension, and gradient thickening to achieve an optimal viscosity threshold to effectively control rheology and achieve timely rigidity stability of the flexible fluid tool.

[0031] The numerical control device can not only adjust the degree of freedom of the conformal polishing system, but also control the conformal path and process indicators, controllably adjust the removal trajectory and residence state parameters, actively adjust the shape and surface fit, and deterministically remove materials, further improving the surface shape accuracy of large-area microstructures of the workpiece, thereby achieving a conformal effect.

[0032] The detector can timely track the material removal process and provide timely feedback when over- or under-throwing occurs, thereby preventing damage to the microstructure due to processing errors.

[0033] The polishing workbench is provided with a fixture for fixing the anode workpiece and a through hole for the electrochemical gradient thickened polishing suspension to flow into the recovery tank after processing.

[0034] The main shaft is provided with an electrochemical gradient thickening polishing suspension flow channel and a current delivery channel, and the electrochemical gradient thickening polishing suspension can flow into the conformal polishing system through the electrochemical gradient thickening polishing suspension flow channel, and the cathode clamp can deliver current to the connected flexible conformal component.

[0035] The anode workpiece is a spherical / aspherical lens substrate material such as single crystal silicon or silicon carbide of an infrared optical system, a micro sensor component, a stainless steel micro gear bolt and nut, etc.

[0036] The commonly used high voltage power supplies for electrochemical machining are silicon rectifier power supplies and thyristor rectifier power supplies. The circuit protection device effectively prevents damage caused by circuit short circuit or excessive load.

[0037] The beneficial effects of the present invention are mainly manifested in:

[0038] 1. A wide variety of workpieces can be processed. The device of the present invention can process different types of workpieces, such as micro-array components, micro-sensor components, micro-gear bolts and nuts, and other basic components.

[0039] 2. Excitation micro-motion structure. A smooth rotor is placed in the inner cavity of the polishing fluid tool, and an eccentric stator is placed in the outer cavity. Force analysis or dynamic distribution is performed to generate an excitation micro-force perpendicular to the axis on the smooth rotor mechanism. The excitation micro-force induces the rotor to form vortex behavior, resulting in the dynamic mechanism of the excitation micro-motion polishing liquid regulation, which promotes the micro-vibration of the flexible fluid to facilitate the residence and dynamic trajectory behavior of the flexible "fluid tool" of micro-abrasive particles. In the area of ​​composite action of excitation micro-motion, efficient conformal removal of materials and regulation of polishing surface accuracy are achieved. Electrochemical thickening and integration of temperature-sensitive or slow-release physicochemical particles (i.e., liquid flow property regulation particles) to regulate the affinity and repellency characteristics of the liquid flow contact structure surface

[0040] 3. Advantages of CNC system. The polishing system can be regulated in three-dimensional space of x-axis, y-axis and z-axis, and can be regulated for parts of different sizes, which is highly compatible with the processing of various parts. In addition, the shape-following path and process indicators are controlled, the removal trajectory and dwell state parameters are controllably adjusted, the shape and surface are actively adjusted to match, and the material is removed deterministically, which further improves the surface accuracy of large-area microstructures of the workpiece.

[0041] 4. Extremely high surface accuracy. Under the action of the electrochemical thickening generator, a specific electrochemical gradient thickening effect is generated, which further regulates the "flexibility" characteristics of the fluid tool. In the exciting micro-motion area, the fluid tool flow has a timely weak rigidity rheology to form a flexible "fluid mold". When the conformal device controls the workpiece and the flexible fluid tool (fluid mold) to produce dynamic movement, the affinity and distance characteristics of the flexible fluid-contact structure surface are regulated to facilitate the micro-abrasive particles to contact the structural surface of the target workpiece over a large area, and the micro-abrasive particles can efficiently remove materials.

[0042] 5. The present invention has relatively low requirements on polishing equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Schematic diagram of the ultra-precision manufacturing device for electrochemical gradient thickening-excitation micro-motion composite conformal polishing.

[0044] Figure 2 Schematic diagram of the polishing method of the electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing device.

[0045] Figure 3 Schematic diagram of the gradient thickening mechanism of suspension during electrochemical gradient thickening polishing.

[0046] Figure 4 Schematic diagram of the polishing auxiliary device of the electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing device.

[0047] Figure 5 Schematic diagram of anode workpiece, where (a) represents a microlens structure, (b) represents a microprism structure, (c) represents a cylindrical array microstructure, and (d) represents a tetrahedron array microstructure;

[0048] Among them, 1. box; 2. circuit controller; 3. landing gear; 4. slide; 5. z-axis guide; 6. x-axis guide; 7. mobile frame; 8. numerical control device; 9. infusion tube; 10. hydraulic pump; 11. storage box; 12. y-axis guide; 13. recovery tank; 14. anode workpiece; 15. polishing workbench; 16. electrochemical thickening generator; 17. circuit protection device; 18. high-voltage power supply; 19. transformer; 20. spindle box; 21. spindle; 22. electrochemical gradient thickening polishing suspension flow channel; 23. current delivery channel; 24. connecting shaft; 25. rotating shaft; 26. flexible conformal component; 27. detector; 28. electrochemical gradient thickening phase; 29. ​​nano-abrasive; 30. stator; 31. rotor; 32. excitation; 33. agglomeration effect; 34. vortex. DETAILED DESCRIPTION

[0049] The present invention will be further described below in conjunction with the accompanying drawings.

[0050] Reference Figure 1 to Figure 5 , an ultra-precision manufacturing method for electrochemical gradient thickening-excitation micro-motion composite conformal polishing, which uses electrochemical gradient thickening phase 28 to induce electrochemical interface reaction to guide the directional movement of charged particles and control the particle aggregation effect of the suspension, and then uses flexible fluid abrasive tools to generate excitation micro-power perpendicular to the axis for efficient conformal removal. This method can not only greatly improve the surface accuracy, but also achieve atomic and near-atomic scale polishing accuracy.

[0051] An electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing device, comprising a box 1, a conformal polishing device, a power supply auxiliary device, an electrochemical gradient thickening polishing suspension conveying device and a polishing auxiliary device, wherein the conformal polishing device comprises, from top to bottom, a spindle box 20, a spindle 21, an electrochemical gradient thickening polishing suspension flow channel 22, a current conveying channel 23, an electrochemical thickening generator 16, a connecting shaft 24, a rotating shaft 25, a flexible conformal component 26 and a detector 27, and the conformal polishing device is located at the middle end of the box 1; the power supply auxiliary device comprises a high-voltage power supply 18, an anode 29, and a cathode 29. The pole clamp 35, the cathode clamp 36, the circuit protection device 17, the transformer 19 and the circuit controller 2, and the power supply auxiliary device are located at the left end of the box body 1; the electrochemical gradient thickening polishing processing suspension liquid conveying device includes an infusion pipe 9, a hydraulic pump 10, a storage box 11 and a recovery tank 13, and the electrochemical gradient thickening polishing processing suspension conveying device is located at the right end of the box body 1; the polishing auxiliary device includes a numerical control device 8, a landing gear 3, a mobile frame 7, a slide 4, an x-axis guide rail 6, a y-axis guide rail 12, a z-axis guide rail 5, an anode workpiece 14, a fixture and a polishing workbench 15, and the polishing device is located inside the box body 1.

[0052] The conformable polishing device includes, from top to bottom, a spindle box 20, a spindle 21, an electrochemical gradient thickening polishing processing suspension flow channel 22, a current delivery channel 23, an electrochemical thickening generator 16, a connecting shaft 24, a rotating shaft 25, a flexible conformable component 26 and a detector 27. The conformable polishing device is located at the middle end of the box body 1; the upper end of the spindle 21 is connected to the spindle box 20, and the lower end is connected to the electrochemical thickening generator 16. An electrochemical gradient thickening polishing processing suspension flow channel 22 and a current delivery channel 23 are opened at the spindle 21. The connecting shaft 24 connects the electrochemical thickening generator 16 and the rotating shaft 25. The flexible conformable component 26 and the detector 27 are installed at the rotating shaft 25.

[0053] The electrochemical thickening generator 16 can realize a controllable gradient change in the viscosity of the electrochemical gradient thickening polishing suspension, and gradient thickening to achieve an optimal viscosity threshold to effectively control the rheology and achieve timely rigidity stability of the flexible fluid tool.

[0054] The flexible conformable member 26 has a rotor disposed in the inner cavity and a stator disposed at the eccentric position of the outer cavity to maintain a certain degree of airtightness. The flexible conformable member 26 can be deformed according to the shape of the target anode workpiece 14 so as to be highly fitted to the surface of the anode workpiece 14. When the flexible conformable member 26 rotates with the rotating shaft 25, the flexible conformable member 26 generates an excitation micro-force perpendicular to the axis, which induces the flexible conformable member 26 to form a vortex behavior, thereby efficiently removing materials in a conformal manner.

[0055] The detector 27 can timely track the material removal process and give timely feedback when over- or under-polishing occurs, thereby preventing damage to the microstructure caused by processing errors.

[0056] The main shaft 21 is provided with an electrochemical gradient thickening polishing suspension flow channel 22 and a current delivery channel 23. The electrochemical gradient thickening polishing suspension can flow into the conformal polishing system through the electrochemical gradient thickening polishing suspension flow channel 22, and the cathode clamp 36 can be delivered to the connected flexible conformal component 26 through current.

[0057] The auxiliary power supply device includes a high-voltage power supply 18, an anode clamp 35, a cathode clamp 36, a circuit protection device 17, a transformer 19 and a circuit controller 2. The auxiliary power supply device is located at the left end of the box 1; the anode of the power supply is connected to the anode workpiece 14 through the circuit protection device 17, and the cathode of the power supply is connected to the flexible conformal component 26 through the transformer 19. The circuit controller 2 is responsible for controlling the circuit power supply and current.

[0058] The high voltage power supply 18 is a silicon rectifier power supply and a thyristor rectifier power supply. The circuit protection device 17 is to effectively prevent damage caused by short circuit or excessive load.

[0059] The electrochemical gradient thickening and polishing suspension liquid conveying device includes an infusion tube 9, a hydraulic pump 10, a storage box 11 and a recovery tank 13. The electrochemical gradient thickening and polishing suspension liquid conveying device is located at the right end of the box body 1; the electrochemical gradient thickening and polishing suspension liquid flows through the infusion tube 9 in turn through the hydraulic pump 10 and the conformal polishing device to reach the inner cavity of the flexible conformal component 26, and then flows into the recovery tank 13 through the through hole of the polishing workbench 15, completing the electrochemical polishing liquid conveying and recovery.

[0060] In this embodiment, the electrochemical gradient thickened polishing suspension contains nano-abrasive particles 29, and the nano-abrasive particles 29 include one or more mixtures of nano-diamond, cubic boron oxide, boron carbide, silicon carbide, silicon nitride, silicon oxide, gallium oxide, iron oxide, magnesium oxide, lithium fluoride, graphite and Al2O3.

[0061] The electrochemical gradient thickening polishing suspension generally includes acidic, neutral and alkaline polishing liquids. For processing silicon-based materials or alloy materials, acidic electrochemical polishing liquids are mainly used, including phosphoric acid, sulfuric acid, perchloric acid, phosphoric acid-sulfuric acid and electrochemical polishing liquids with various additives. Electrochemical thickening incorporates slow-release physical and chemical particles (i.e., liquid flow property regulating particles) to regulate the affinity and repellency characteristics of the liquid flow contact structure surface. Slow-release physical and chemical particles are generally sodium polyacrylate, polyvinyl alcohol or polyurethane thickeners, etc.

[0062] The electrochemical gradient thickening polishing suspension of this embodiment includes the following components in percentage by mass: nano-abrasive particles, pH adjusting agent, slow-release chemical particles, oxidant and electrochemical gradient thickening phase (ferrous sulfate, sodium sulfite, etc.) are added to ultrapure water at 25°C to prepare the polishing suspension. Among them, the mass fraction of nano-abrasive particles is between 7% and 20%, the mass fraction of pH adjusting agent is between 0.05% and 1.0%, the mass fraction of slow-release chemical particles is between 0.05% and 1.0%, the mass fraction of oxidant is between 0.05% and 0.1%, and the mass fraction of electrochemical gradient thickening phase is between 1% and 10%.

[0063] The polishing auxiliary device includes a numerical control device 8, a landing gear 3, a mobile frame 7, a slide 4, an x-axis guide rail 6, a y-axis guide rail 12, a z-axis guide rail 5, an anode workpiece 14, a fixture and a polishing workbench 15. The polishing device is located inside the box 1; the landing gear 3, the mobile frame 7 and the slide 4 are respectively connected to each other through the x-axis guide rail 6, the y-axis guide rail 12 or the z-axis guide rail 5, and the numerical control device 8 controls their movement. The z-axis guide rail 5 on the slide 4 is connected to the conformal polishing device. The lower end of the conformal polishing device is a polishing workbench 15, and a fixture is installed on the polishing workbench 15, and an anode tool is installed on the fixture.

[0064] The numerical control device 8 can not only adjust the degree of freedom of the conformal polishing system, but also control the conformal path and process indicators, controllably adjust the removal trajectory and residence state parameters, actively adjust the shape surface fit, and deterministically remove materials, further improving the surface shape accuracy of the large-area microstructure of the workpiece, thereby achieving a conformal effect.

[0065] The polishing table 15 is provided with a fixture for fixing the anode workpiece 14. The polishing table 15 is provided with a through hole so that the electrochemical gradient thickened polishing suspension can flow into the recovery tank 13 after processing.

[0066] The anode workpiece 14 is a spherical / aspherical lens substrate material such as single crystal silicon or silicon carbide of an infrared optical system, a micro sensor component, a stainless steel micro gear bolt and nut, etc.

[0067] An electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method comprises the following steps:

[0068] (1) placing the anode workpiece 14 on the polishing table 15, and connecting the anode clamp 35 to the anode workpiece 14, and connecting the cathode clamp 36 to the flexible conformal member 26;

[0069] (2) Turning on the numerical control device 8 to control the path and process index of the flexible conformable member 26 so that the starting point fits on the anode workpiece 14;

[0070] (3) adding the electrochemical gradient thickened polishing suspension containing the nano-abrasive particles 29 into the storage box 11, turning on the hydraulic pump 10, and allowing the electrochemical gradient thickened polishing suspension to flow into the conformal polishing device along the infusion tube 9;

[0071] (4) Turn on the circuit controller 2 and the electrochemical thickening generator 16, the electrochemical gradient thickening phase 28 induces the electrochemical interface reaction to guide the directional movement of the charged particles and control the particle aggregation effect of the suspension, and the liquid flow of the flexible conformable component 26 weakens the rigidity rheology in time to form a flexible "fluid mold";

[0072] (5) Turn on the spindle box 20, and generate an exciting micro-force perpendicular to the axis on the rotating flexible "fluid mold". The exciting micro-force induces the flexible "fluid mold" to form a vortex behavior, resulting in the dynamic mechanism of the exciting micro-motion polishing liquid regulation, which promotes the micro-vibration of the flexible fluid to facilitate the residence and dynamic trajectory behavior of the micro-abrasive flexible "fluid mold". In the area of ​​composite action of exciting micro-motion, efficient conformal removal of materials and regulation of polishing surface accuracy are achieved, thereby realizing a new method of electrochemical gradient thickening-exciting micro-motion composite conformal ultra-precision manufacturing.

[0073] Example 1

[0074] The present invention is used for processing a silicon carbide microlens structure with a size of 1.5 mm in processing structure period and 0.5 mm in height ( Figure 5 (a)). This method and device can make the surface roughness Ra of the silicon carbide microlens structure less than 2nm and the shape accuracy PV less than 200nm.

[0075] The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing comprises the following steps:

[0076] (1) placing the microlens workpiece on the polishing table 15, and connecting the anode clamp 35 to the microlens workpiece, and connecting the cathode clamp 36 to the flexible conformal member 26;

[0077] (2) Turning on the numerical control device 8 to control the path and process index of the flexible conformable member 26 so that the starting point fits on the microlens workpiece;

[0078] (3) adding the electrochemical gradient thickened polishing suspension containing the nano-abrasive particles 29 into the storage box 11, turning on the hydraulic pump 10, and allowing the electrochemical gradient thickened polishing suspension to flow into the conformal polishing device along the infusion tube 9;

[0079] (4) Turn on the circuit controller 2 and the electrochemical thickening generator 16, the electrochemical gradient thickening phase 28 induces the electrochemical interface reaction to guide the directional movement of the charged particles and control the particle aggregation effect of the suspension, and the liquid flow of the flexible conformable component 26 weakens the rigidity rheology in time to form a flexible "fluid mold";

[0080] (5) Turn on the spindle box 20, and generate an exciting micro-force perpendicular to the axis on the rotating flexible "fluid mold". The exciting micro-force induces the flexible "fluid mold" to form a vortex behavior, resulting in the dynamic mechanism of the exciting micro-motion polishing liquid regulation, which promotes the micro-vibration of the flexible fluid to facilitate the residence and dynamic trajectory behavior of the micro-abrasive flexible "fluid mold". In the area of ​​composite action of exciting micro-motion, efficient conformal removal of materials and regulation of polishing surface accuracy are achieved, thereby realizing a new method of electrochemical gradient thickening-exciting micro-motion composite conformal ultra-precision manufacturing.

[0081] Example 2

[0082] The present invention is used for processing a silicon nitride microprism structure with a size of 2 mm in the processing structure period and 0.6 mm in height ( Figure 5 (b)). This method and device can make the surface roughness of silicon nitride microprism structure Ra <2.5nm and the shape accuracy PV <200nm.

[0083] The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing comprises the following steps:

[0084] (1) placing the microprism workpiece on the polishing table 15, and connecting the anode clamp 35 to the microprism workpiece, and connecting the cathode clamp 36 to the flexible conformable member 26;

[0085] (2) Turning on the numerical control device 8 to control the path and process index of the flexible conformable member 26 so that the starting point fits on the microprism workpiece;

[0086] (3) adding the electrochemical gradient thickened polishing suspension containing the nano-abrasive particles 29 into the storage box 11, turning on the hydraulic pump 10, and allowing the electrochemical gradient thickened polishing suspension to flow into the conformal polishing device along the infusion tube 9;

[0087] (4) Turn on the circuit controller 2 and the electrochemical thickening generator 16, the electrochemical gradient thickening phase 28 induces the electrochemical interface reaction to guide the directional movement of the charged particles and control the particle aggregation effect of the suspension, and the liquid flow of the flexible conformable component 26 weakens the rigidity rheology in time to form a flexible "fluid mold";

[0088] (5) Turn on the spindle box 20, and generate an exciting micro-force perpendicular to the axis on the rotating flexible "fluid mold". The exciting micro-force induces the flexible "fluid mold" to form a vortex behavior, resulting in the dynamic mechanism of the exciting micro-motion polishing liquid regulation, which promotes the micro-vibration of the flexible fluid to facilitate the residence and dynamic trajectory behavior of the micro-abrasive flexible "fluid mold". In the area of ​​composite action of exciting micro-motion, efficient conformal removal of materials and regulation of polishing surface accuracy are achieved, thereby realizing a new method of electrochemical gradient thickening-exciting micro-motion composite conformal ultra-precision manufacturing.

[0089] Example 3

[0090] The present invention is used for processing single crystal silicon cylindrical array microstructures with a size of: the processing structure period is designed to be 1.8 mm, and the height is designed to be 0.4 mm ( Figure 5 (c)). This method and device can make the surface roughness of the single crystal silicon cylindrical array microstructure Ra <2.3nm and the shape accuracy PV <200nm.

[0091] The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing comprises the following steps:

[0092] (1) placing a cylindrical array microstructure workpiece on a polishing table 15, and connecting an anode clamp 35 to the cylindrical array microstructure workpiece, and connecting a cathode clamp 36 to the flexible conformal member 26;

[0093] (2) Turning on the numerical control device 8 to control the path and process index of the flexible conformable member 26 so that the starting point fits on the cylindrical array microstructure workpiece;

[0094] (3) adding the electrochemical gradient thickened polishing suspension containing the nano-abrasive particles 29 into the storage box 11, turning on the hydraulic pump 10, and allowing the electrochemical gradient thickened polishing suspension to flow into the conformal polishing device along the infusion tube 9;

[0095] (4) Turn on the circuit controller 2 and the electrochemical thickening generator 16, the electrochemical gradient thickening phase 28 induces the electrochemical interface reaction to guide the directional movement of the charged particles and control the particle aggregation effect of the suspension, and the liquid flow of the flexible conformable component 26 weakens the rigidity rheology in time to form a flexible "fluid mold";

[0096] (5) Turn on the spindle box 20, and generate an exciting micro-force perpendicular to the axis on the rotating flexible "fluid mold". The exciting micro-force induces the flexible "fluid mold" to form a vortex behavior, resulting in the dynamic mechanism of the exciting micro-motion polishing liquid regulation, which promotes the micro-vibration of the flexible fluid to facilitate the residence and dynamic trajectory behavior of the micro-abrasive flexible "fluid mold". In the area of ​​composite action of exciting micro-motion, efficient conformal removal of materials and regulation of polishing surface accuracy are achieved, thereby realizing a new method of electrochemical gradient thickening-exciting micro-motion composite conformal ultra-precision manufacturing.

[0097] The contents described in the embodiments of this specification are merely enumerations of implementation forms of the inventive concept and are for illustrative purposes only. The protection scope of the present invention should not be considered to be limited to the specific forms described in this embodiment, and the protection scope of the present invention also extends to equivalent technical means that can be thought of by ordinary technicians in this field based on the inventive concept.

Claims

1. An electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method, characterized in that: The electrochemical gradient thickening phase is used to induce electrochemical interfacial reactions to guide the directional movement of charged particles and control the particle aggregation effect of the suspension. Then, the flexible fluid abrasive tool is used to generate excitation micro-power perpendicular to the axis for efficient conformal removal.

2. The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method according to claim 1, characterized in that: The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method comprises the following steps: (1) placing the anode workpiece on a polishing workbench, connecting the anode clamp to the anode workpiece, and connecting the cathode clamp to the flexible conformable member; (2) Turn on the numerical control device to control the path and process index of the flexible conformable component so that the starting point fits on the anode workpiece; (3) adding an electrochemical gradient thickened polishing suspension containing nano-abrasive particles into a storage box, turning on a hydraulic pump, and allowing the electrochemical gradient thickened polishing suspension to flow into a conformal polishing device along a liquid infusion tube; (4) Turn on the circuit controller and the electrochemical thickening generator, the electrochemical gradient thickening phase induces the electrochemical interface reaction to guide the directional movement of the charged particles and control the particle aggregation effect of the suspension, and the flexible conformable component flow weakens the rigidity rheology in time to form a flexible "fluid mold"; (5) The spindle box is turned on, and the rotating flexible "fluid mold" generates an exciting micro-force perpendicular to the axis. The exciting micro-force induces the flexible "fluid mold" to form a vortex behavior, resulting in the dynamic mechanism of the exciting micro-motion polishing liquid regulation, which promotes the micro-vibration of the flexible fluid to facilitate the residence and dynamic trajectory behavior of the micro-abrasive flexible "fluid mold". In the area of ​​the exciting micro-motion composite action, the material is efficiently removed in a conformal manner and the polishing surface accuracy is regulated.

3. The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method according to claim 2, characterized in that: In the (1), a rotor is arranged in the inner cavity of the flexible conformable component, and a stator is arranged at an eccentric position of the outer cavity to maintain a certain airtightness; the flexible conformable component is deformed according to the shape of the target anode workpiece so as to be highly fitted to the surface of the anode workpiece; when the flexible conformable component rotates with the rotating shaft, the flexible conformable component generates an excitation micro-force perpendicular to the axis, and the excitation micro-force induces the flexible conformable component to form a vortex behavior, thereby efficiently removing materials in a conformal manner.

4. The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method according to claim 2, characterized in that: In (4), the electrochemical gradient thickening phase is porous microsphere particles. When the porous microsphere particles are integrated into the electrochemical gradient thickening polishing suspension, a slow chemical reaction occurs to generate negatively charged particles. At this time, the negatively charged particles induce the positively charged metal nanoabrasives to produce a clustering effect.

5. The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method according to claim 2, characterized in that: In (3), the nano-abrasive particles include one or a mixture of two or more of nano-diamond, cubic boron oxide, boron carbide, silicon carbide, silicon nitride, silicon oxide, gallium oxide, iron oxide, magnesium oxide, lithium fluoride, graphite or Al2O3.

6. The electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method according to claim 2, characterized in that: In said (3), the electrochemical gradient thickened polishing processing suspension includes acidic, neutral or alkaline polishing liquid; for processing silicon-based materials or alloy materials, an acidic electrochemical polishing liquid is used, including phosphoric acid, sulfuric acid, perchloric acid, phosphoric acid-sulfuric acid and electrochemical polishing liquids with various additives; electrochemical thickening incorporates slow-release physical and chemical particles, i.e., liquid flow property regulating particles, to regulate the affinity and repellency characteristics of the liquid flow contact structure surface.

7. A device for realizing the electrochemical gradient thickening-excitation micro-motion composite conformal polishing ultra-precision manufacturing method as claimed in claim 1, characterized in that: It includes a box, a conformable polishing device, a power supply auxiliary device, an electrochemical gradient thickening polishing suspension conveying device and a polishing auxiliary device, wherein the conformable polishing device is located at the middle end of the box; the power supply auxiliary device is located at the left end of the box; the electrochemical gradient thickening polishing suspension conveying device is located at the right end of the box; and the polishing auxiliary device is located inside the box; The conformable polishing device comprises, from top to bottom, a spindle box, a spindle, an electrochemical gradient thickening polishing suspension flow channel, a current delivery channel, an electrochemical thickening generator, a connecting shaft, a rotating shaft, a flexible conformable component and a detector. The upper end of the spindle is connected to the spindle box, the lower end of the spindle is connected to the electrochemical thickening generator, an electrochemical gradient thickening polishing suspension flow channel and a current delivery channel are opened at the spindle, the connecting shaft connects the electrochemical thickening generator and the rotating shaft, and the flexible conformable component and the detector are installed at the rotating shaft.

8. The device according to claim 7, characterized in that The power supply auxiliary device includes a high-voltage power supply, an anode clamp, a cathode clamp, a circuit protection device, a transformer and a circuit controller. The anode of the power supply is connected to the anode workpiece through the circuit protection device, the cathode of the power supply is connected to the flexible conformal component through the transformer, and the circuit controller is responsible for controlling the circuit power supply and current.

9. The device according to claim 7 or 8, characterized in that The electrochemical gradient thickening polishing suspension liquid conveying device includes an infusion tube, a hydraulic pump, a storage box and a recovery tank. The electrochemical gradient thickening polishing suspension liquid flows through the infusion tube in sequence through the hydraulic pump and the conformal polishing device to reach the inner cavity of the flexible conformal component, and then flows into the recovery tank through the through hole of the polishing workbench, completing the electrochemical polishing liquid conveying and recovery.

10. The device according to claim 7 or 8, characterized in that The polishing auxiliary device includes a numerical control device, a landing gear, a mobile frame, a slide, an x-axis guide rail, a y-axis guide rail, a z-axis guide rail, an anode workpiece, a fixture and a polishing workbench. The landing gear, the mobile frame and the slide are respectively connected to each other through the x-axis guide rail, the y-axis guide rail or the z-axis guide rail. The numerical control device controls their movement. The z-axis guide rail on the slide is connected to the conformal polishing device. The lower end of the conformal polishing device is a polishing workbench. A fixture is installed on the polishing workbench, and an anode tool is installed on the fixture.

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