Graphene composite nanoparticle abrasive flexible fluid electric field-ultrasonic auxiliary polishing method and device

Abstract

A graphene composite nanoparticle abrasive flexible fluid electric field-ultrasonic auxiliary polishing method comprises the following steps that S1, primary chemical bonding and graft copolymerization of graphene and nanoparticles are achieved through a dynamic high shear field-ultrasonic synergistic induction method; and then compounding the primary abrasive material and the secondary graphene into the graphene composite nano-particle abrasive material of a multi-layer structured coating system with a core-shell structure through a dynamic high shear field-ultrasonic synergistic induction method. S2, arranging and moving of the particles on the surface are adjusted by applying an electric field; s3, ultrasonic waves are applied in the polishing process, contact between particles and the surface is improved, and surface defects are removed; and S4, the micro state of the abrasive particles and the surface state of the workpiece in the polishing process are tracked. The invention further provides a device for implementing the method. The polishing precision, the surface smoothness, the polishing speed and the polishing uniformity are improved, and the energy consumption is reduced; the polishing consistency and stability are improved, the machining cost is reduced, and the rejection rate is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of ultra-precision polishing, and specifically relates to a graphene composite nano-particle abrasive flexible fluid electric field-ultrasound assisted polishing method and device. Background Art

[0002] As a new type of carbon-based material, graphene has shown excellent performance and application potential in many fields, including electronics, optics, materials science, etc. It has excellent electrical conductivity, thermal conductivity and mechanical strength, so it has been widely studied and applied.

[0003] In the field of polishing, traditional polishing methods usually use abrasives, polishing fluids and mechanical forces to improve the quality of material surfaces. However, these methods may have some disadvantages, such as easy to cause surface damage, high energy consumption, long processing cycle, etc. Therefore, researchers began to explore new polishing methods to address the limitations of traditional methods. Applied electric field and ultrasonic assistance are two common surface treatment technologies. Applied electric field can change the charge distribution and movement mode on the surface of the material, thereby affecting the movement and arrangement of particles during polishing, thereby improving the polishing effect. Ultrasonic assistance uses the high-frequency vibrations generated by ultrasonic waves in liquids to improve the polishing effect, such as making particles better contact with the surface and removing surface defects.

[0004] Prior art China Publication No. CN109848821A, the invention provides a green and environmentally friendly chemical mechanical polishing method for nickel alloys. The nickel alloy is first ground, and then rough polishing and fine polishing are performed. During rough polishing, the polishing abrasive is α-alumina with an average particle size of 3-5μm, the polishing liquid is deionized water, and the polishing pad is polyurethane. During fine polishing, the ceramic abrasive is silicon oxide, α-alumina, cerium oxide, and magnesium oxide with an average particle size of 20-60nm and a weight percentage of 0.5% to 3%; the complexing agent is sodium iminodisuccinate and sodium citrate with a weight percentage of 0.5% to 2%; the pH adjuster is tartaric acid and acetic acid with a weight percentage of 0.5% to 2%, and the pH of the polishing liquid is adjusted to 3-5; the polishing pad is frosted leather. The measurement range of the nickel alloy after polishing is 50×70μm 2 , the surface roughness Ra reaches 0.4-0.7nm, achieving ultra-smooth and ultra-low damage chemical mechanical polishing of nickel. The polishing process is easily affected by the abrasive particle size. Small particle size can easily reduce the polishing efficiency, and high particle size will cause scratches and pitting defects on the polished surface to a certain extent.

[0005] Prior art China Publication No. CN107164764A, the invention provides an environmentally friendly chemical mechanical polishing method for copper. The ceramic abrasive particles are silicon dioxide, aluminum oxide, magnesium oxide, and cerium dioxide, and the average particle size of the particles is 20-120nm, and the weight percentage is 1% to 6%. The amino organic matter is proline, glucosamine, chitosan oligosaccharide, chitin, and cellulose, and the weight percentage is 0.4% to 2.5%. The pH value of the polishing liquid is 3-7. The copper sheet is ground, and the grinding liquid is deionized water, and then the copper sheet is chemically mechanically polished. During polishing, the rotation speed of the workpiece and the polishing disk are both 40-80rpm, the pressure is 20-40kPa, the polishing liquid flow rate is 60-80mL / min, and the polishing time is 5-10min. The measurement range of the polished copper sheet is 50×70μm 2 , the surface roughness Ra reaches 0.4-0.7nm. The present invention realizes ultra-smooth ultra-low damage environmentally friendly chemical mechanical polishing of copper. To a certain extent, the polishing result is easily affected by the abrasive concentration, which will lead to the removal rate and surface polishing scratches.

[0006] Prior art publication number CN115464472A, the invention provides an equipment and process method for adaptive ultrasonic chemical mechanical polishing of wheel hub mold, including a bed and an ultrasonic generator installed in the bed, an upper bracket, a cable, a fan, a flange, a movable bracket, a transducer, a horn, a Z-axis lifting platform, a translation workbench, a positioning pin, a working pool, a compressed air pump, a numerical control system and an airbag. The present invention has a surface adaptive function, and can adaptively transform and fit with the convex and concave surface of the workpiece. The whole process does not require model building, scanning, or excessive manual intervention, which can significantly reduce labor. Through densely deployed ultrasonic enhanced chemical mechanical polishing, the entire surface to be processed is processed at the same time, with high processing efficiency, good uniformity, good surface consistency after polishing, high precision, and the surface roughness of the wheel hub mold after polishing can reach Ra0.446~1.442μm. At the same time, it can also be applied to parts other than wheel hub molds, and has strong versatility. The polishing process has high energy consumption, and to some extent has energy-saving and environmentally friendly polishing limitations. Summary of the invention

[0007] In order to overcome the shortcomings of the existing technology and solve the problems of surface damage, high energy consumption and long processing cycle caused by the above-mentioned traditional polishing methods, the present invention provides a graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method and device. The present invention develops a new type of graphene composite nanoparticle abrasive, which utilizes the high strength and high conductivity characteristics of graphene to significantly improve the grinding efficiency and durability of the abrasive. This abrasive can provide better thermal conductivity and enhanced mechanical properties, and is suitable for high-precision and high-demand polishing processes. The present invention uses a flexible fluid as a carrier, integrates electric field technology to manipulate the fluid, and applies directional force to the abrasive particles through the electric field to achieve uniform distribution and effective cutting of the abrasive on the workpiece surface. And ultrasonic technology is provided to enhance the dynamic response of abrasive particles and improve the polishing efficiency of abrasives. It can not only change the charge distribution and movement mode on the surface of the material, thereby affecting the movement and arrangement of particles during the polishing process, thereby improving the polishing effect, but also utilize the high-frequency vibration generated by ultrasonic waves in the liquid to improve the polishing effect.

[0008] The technical solution adopted by the present invention to solve its technical problem is:

[0009] A graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method comprises the following steps:

[0010] S1. Firstly, chemical bonding and graft copolymerization of primary graphene and nanoparticles are achieved by a dynamic high shear field-ultrasound synergistic induction method, and then the primary abrasive and secondary graphene are compounded by a dynamic high shear field-ultrasound synergistic induction method to form a graphene composite nanoparticle abrasive having a core-shell structured multilayer coating system (incomplete coating, including a cutting exposed area);

[0011] S2, applying an electric field during the polishing process through electrodes, a power supply and a controller in the electric field application component, a polishing component and an infusion component to adjust the arrangement and movement of particles on the surface;

[0012] S3, using an ultrasonic auxiliary component to apply ultrasonic waves during polishing to improve the contact between particles and the surface and remove surface defects;

[0013] S4. Track the microscopic state of abrasive particles and the surface state of the workpiece during polishing.

[0014] Further, in step S1, the nanoparticles are one or a mixture of two or more of metal oxides, carbides or borides, the proportion of graphene is 10% to 50% by weight, the particle size of the nanoparticles is in the range of 10-100 nanometers, the dynamic high shear field-ultrasound synergistic induction method is to process in a high shear homogenizer, use high-speed fluid movement to form strong shear force and eddy current effect, so that the nanoparticles are evenly embedded in the graphene flakes, turn on the ultrasonic device (preferably with a frequency of 30kHz), and combine with high shear shear force to promote the graphene flakes to form a multi-layer coating structure on the surface of the abrasive, wherein the multi-layer coating structure is incompletely coated and contains a cutting exposed area. The graphene and nanoparticles use dynamic high shear field and ultrasonic synergistic induction technology, and utilize the high shear force of the fluid and ultrasonic cavitation to achieve precise compounding of graphene and nanoparticles in the process of multi-level dispersion, dynamic reorganization and multi-layer coating. The new composite abrasive is a multifunctional graphene composite nanoparticle abrasive with a core-shell structure. Its hard core provides high strength and wear resistance, and the graphene shell gives it multiple excellent properties such as electrical conductivity, thermal conductivity, self-lubrication and anti-agglomeration. The primary graphene is single-layer graphene, multi-layer graphene or graphene oxide, and the secondary graphene is graphene with different modification methods, including graphene oxide or reduced graphene oxide.

[0015] Furthermore, in step S2, the electric field application component includes an electrode and a power supply and a controller electrically connected thereto, and the controller is used to monitor and adjust the electric field strength, ultrasonic frequency, amplitude and duty cycle, as well as polishing pressure and time in real time. The electric field and ultrasonic wave are used for microstructure regulation, and the microstructure regulation controls the distribution density, size and morphology of graphene and nanoparticles by adjusting the parameters of the electric field and ultrasonic treatment.

[0016] Preferably, the controller automatically adjusts the electric field parameters and ultrasonic parameters according to the conductivity, hardness and surface roughness of the workpiece material through sensor input.

[0017] Furthermore, in step S3, the ultrasonic auxiliary component includes an ultrasonic generator, an ultrasonic transducer, a horn and a sensor, and the ultrasonic generator is used to emit ultrasonic waves with adjustable ultrasonic frequency and amplitude to the polishing liquid.

[0018] In step S2, the polishing assembly includes a polishing head, a fixture, a workpiece, a polishing pad, a polishing disc and a frame, wherein the frame is used to support and carry the polishing disc, the fixture, the ultrasonic auxiliary component, the electric field application component and the infusion component, the polishing head is used to polish the workpiece, and the polishing disc is used to hold the polishing liquid and the workpiece.

[0019] In step S2, the infusion assembly includes a catheter, a hydraulic pump and a box, the box is used to store the prepared polishing liquid, the catheter is used to connect the catheters, and the hydraulic pump is used to extract the polishing liquid in the box and transport it to the polishing plate through the catheter.

[0020] A graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing device comprises an electric field applying component, an ultrasonic auxiliary component, a polishing component and an infusion component, wherein the polishing component comprises a polishing head, a fixture, a polishing disc and a frame, wherein the frame is used to support and carry the polishing disc, the fixture, the ultrasonic auxiliary component, the electric field applying component and the infusion component, wherein the polishing head is used to polish a workpiece, wherein the polishing disc is used to contain polishing liquid and the workpiece, wherein the polishing head is located above the polishing disc, wherein the ultrasonic auxiliary component is located above the polishing disc, wherein the electric field applying component is located on the side of the polishing disc, wherein the outlet of the liquid guide tube of the infusion component is aligned with the processing station of the polishing head and the workpiece.

[0021] Furthermore, the electric field application component includes electrodes and a power supply and controller electrically connected thereto, the controller being used to monitor and adjust the electric field intensity, ultrasonic frequency, amplitude and duty cycle, as well as polishing pressure and time in real time, the electric field and ultrasonic waves being used for microstructure regulation, and the microstructure regulation controls the distribution density, size and morphology of graphene and nanoparticles by adjusting the parameters of the electric field and ultrasonic processing.

[0022] Furthermore, the ultrasonic auxiliary component includes an ultrasonic generator, an ultrasonic transducer, a horn and a sensor. The ultrasonic generator is used to emit ultrasonic waves with adjustable ultrasonic frequency and amplitude to the polishing liquid. The ultrasonic generator is installed on the top of the polishing disk through a movable arm, and the distance can be adjusted to accommodate workpieces of different sizes. The ultrasonic generator is connected to the ultrasonic transducer, and the ultrasonic transducer is connected to the horn. The polishing head is installed at the bottom of the horn, and the sensor is installed on the frame.

[0023] The controller automatically adjusts electric field parameters and ultrasonic parameters according to the conductivity, hardness and surface roughness of the workpiece material through sensor input.

[0024] The infusion assembly comprises a liquid guide tube, a hydraulic pump and a box body. The box body is used to store the prepared polishing liquid. The hydraulic pump is used to extract the polishing liquid in the box body and transport it to the polishing plate through the liquid guide tube.

[0025] The beneficial effects of the present invention are mainly manifested in:

[0026] 1. In the present invention, the primary graphene is firstly compounded with nano-scale metal oxides, carbides or borides by a dynamic high shear field-ultrasonic synergistic induction method, and firmly combined with nanoparticles. Through its excellent conductivity and mechanical properties, the electric field and vibration are uniformly transmitted to the core of the nanoparticles. Then, the secondary graphene is compounded with the basic adsorption abrasive by this method, providing high hardness and toughness, protecting the inner nanoparticles, preventing them from direct fragmentation or wear, and increasing the service life of the abrasive. This allows the abrasive to more effectively remove microscopic concave-convex surfaces of the material during the polishing process, thereby improving the polishing accuracy and surface finish. The introduction of ultrasonic waves not only increases the interaction force between the abrasive particles and the workpiece surface, but also helps release the tiny particles embedded by the abrasive through vibration, further improving the polishing speed and uniformity. At the same time, the application of the electric field makes the abrasive particles more evenly distributed on the workpiece surface, reducing the situation of local over-polishing or under-polishing.

[0027] 2. In the present invention, compared with the traditional polishing method, the applied electric field and ultrasound-assisted polishing method may require less mechanical energy, thereby reducing energy consumption and reducing environmental burden;

[0028] 3. In the present invention, the applied electric field and ultrasonic assisted technology can effectively remove surface defects, improve surface finish and flatness, thereby improving the surface quality of the material and making it have higher optical and mechanical properties. The applied electric field and ultrasonic assisted device is usually equipped with a controller, which can accurately adjust the electric field intensity, frequency and ultrasonic parameters to achieve precise control of the polishing process and improve the consistency and stability of polishing;

[0029] 4. In the present invention, the method is not only applicable to the polishing of a single workpiece, but can also be applied to the surface treatment of other materials, such as metals, ceramics, etc., thereby expanding its application scope in the field of material processing and manufacturing;

[0030] 5. In the present invention, although the introduction of the external electric field and ultrasonic assisted technology may require a certain initial investment, in the long run, due to the improved polishing efficiency and quality, it can reduce processing costs and reduce scrap rates, thereby bringing long-term economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the three-dimensional structure of the polishing device of the present invention;

[0032] Figure 2 It is a front view structural schematic diagram of the polishing device of the present invention;

[0033] Figure 3 This is a schematic diagram of the composite state of graphene and nanoparticles after the dynamic high shear field-ultrasound synergistic induction method of the present invention;

[0034] Figure 4 It is a schematic diagram of the composite state of secondary graphene and initial abrasive after the dynamic high shear field-ultrasound synergistic induction method of the present invention;

[0035] Figure 5 This is an enlarged schematic diagram of a multifunctional nano-composite abrasive structure having a core-shell structure prepared by the present invention;

[0036] Figure 6 Schematic diagram of the polishing surface removal mechanism of the present invention, wherein (a) is the first half of the processing flow, and (b) is the second half of the processing flow;

[0037] Figure 7 It is a schematic diagram of the effect before and after polishing of the workpiece surface of the present invention.

[0038] In the figure: 1. ultrasonic generator; 2. ultrasonic transducer; 5. horn; 6. polishing head; 7. fixture; 8. workpiece; 10. liquid guide tube; 11. hydraulic pump; 12. box; 13. polishing disc; 14. rack; 15. sensor; 18. electrode; 101. primary graphene; 102. nanoparticles; 103. electric field; 104. debris; 105 strong shear treatment; 106. interface bonding layer; 107. cavitation bubbles; 108. ultrasonic vibration wave; 109. secondary graphene; 110. primary abrasive; 111. graphene composite nanoparticle abrasive; 112. graphene coating; 113. self-lubricating property; 114. anti-agglomeration property; 115. electrical and thermal conductivity. DETAILED DESCRIPTION

[0039] The present invention will be further described below in conjunction with the accompanying drawings.

[0040] Reference Figure 1 to Figure 7 , a graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method, comprising the following steps:

[0041] S1. Firstly, chemical bonding and graft copolymerization of primary graphene and nanoparticles are achieved by a dynamic high shear field-ultrasound synergistic induction method, and then the primary abrasive and secondary graphene are compounded by a dynamic high shear field-ultrasound synergistic induction method to form a graphene composite nanoparticle abrasive having a core-shell structured multilayer coating system (incomplete coating, including a cutting exposed area);

[0042] S2, applying an electric field during the polishing process through electrodes, a power supply and a controller in the electric field application component, a polishing component and an infusion component to adjust the arrangement and movement of particles on the surface;

[0043] S3, using an ultrasonic auxiliary component to apply ultrasonic waves during polishing to improve the contact between particles and the surface and remove surface defects;

[0044] S4. Track the microscopic state of abrasive particles and the surface state of the workpiece during polishing.

[0045] Further, in step S1, the nanoparticles are one or a mixture of two or more of metal oxides, carbides or borides, the proportion of graphene is 10% to 50% by weight, the particle size of the nanoparticles is in the range of 10-100 nanometers, the dynamic high shear field-ultrasound synergistic induction method is to process in a high shear homogenizer, use high-speed fluid movement to form strong shear force and eddy current effect, so that the nanoparticles are evenly embedded in the graphene flakes, turn on the ultrasonic device (preferably with a frequency of 30kHz), and combine with high shear shear force to promote the graphene flakes to form a multi-layer coating structure on the surface of the abrasive, wherein the multi-layer coating structure is incompletely coated and contains a cutting exposed area. The graphene and nanoparticles are precisely compounded in the process of multi-stage dispersion, dynamic reorganization and multi-layer coating by using dynamic high shear field and ultrasonic synergistic induction technology, and utilizing the high shear force of the fluid and ultrasonic cavitation. The novel composite abrasive is a multifunctional graphene composite nanoparticle abrasive with a core-shell structure. Its hard core provides high strength and wear resistance, and the graphene shell gives it multiple excellent properties such as electrical conductivity, thermal conductivity, self-lubrication and anti-agglomeration. The primary graphene is single-layer graphene, multi-layer graphene or graphene oxide, and the secondary graphene is graphene with different modification methods, including graphene oxide or reduced graphene oxide.

[0046] A graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing device, comprising an electric field applying component, an ultrasonic auxiliary component, a polishing component and an infusion component, wherein the polishing component comprises a polishing head 6, a fixture 7, a polishing disc 13 and a frame 14, wherein the frame 14 is used to support and carry the polishing disc 13, the fixture 7, the ultrasonic auxiliary component, the electric field applying component and the infusion component, wherein the polishing head 6 is used to polish a workpiece 8, wherein the polishing disc 13 is used to contain polishing liquid and the workpiece 8, wherein the polishing head 6 is located above the polishing disc 13, wherein the ultrasonic auxiliary component is located above the polishing disc 13, wherein the electric field applying component is located on the side of the polishing disc 13, wherein the outlet of the liquid guide tube 10 of the infusion component is aligned with the processing station of the polishing head 6 and the workpiece 8.

[0047] The electric field application component includes an electrode 18 and a power supply and a controller electrically connected thereto. The controller is used to monitor and adjust the electric field strength, ultrasonic frequency, amplitude and working cycle, as well as polishing pressure and time in real time. The electric field and ultrasonic waves are used for microstructure regulation, and the microstructure regulation controls the distribution density, size and morphology of graphene and nanoparticles by adjusting the parameters of the electric field and ultrasonic treatment.

[0048] The ultrasonic auxiliary component includes an ultrasonic generator 1, an ultrasonic transducer 2, a horn 5 and a sensor 15. The ultrasonic generator 1 is used to emit ultrasonic waves with adjustable ultrasonic frequency and amplitude to the polishing liquid. The ultrasonic generator 1 is installed on the top of the polishing disc 13 through a movable arm, and the distance can be adjusted to adapt to workpieces of different sizes. The ultrasonic generator 1 is connected to the ultrasonic transducer 2, and the ultrasonic transducer 2 is connected to the horn 5. The polishing head 6 is installed at the bottom of the horn 5, and the sensor 15 is installed on the frame 14.

[0049] The controller automatically adjusts the electric field parameters and ultrasonic parameters according to the conductivity, hardness and surface roughness of the workpiece material input through the sensor 15.

[0050] The infusion assembly includes a catheter 10 , a hydraulic pump 11 and a box 12 . The box 12 is used to store the prepared polishing liquid. The hydraulic pump 11 is used to extract the polishing liquid in the box 12 and transport it to the polishing plate 13 through the catheter 10 .

[0051] Example 1

[0052] The present invention is used for processing flat and thin parts of hard and brittle materials, optical materials, etc. A 304 stainless steel plate is selected as the polishing workpiece, with a size of 50mm×50mm×2mm, and the processing steps are as follows:

[0053] 1. Fix the workpiece 8 on the polishing disc 13 of the experimental equipment with a fixture 7 or a bonding resin; prepare a composite polishing liquid, and use a primary abrasive 110 prepared by a dynamic high shear field-ultrasonic synergistic induction method with a mass ratio of 1:1 of 50-nanometer primary graphene sheets 101 and 100-nanometer aluminum oxide particles; slowly add the basic adsorbed graphene-nanoparticle abrasive to the secondary graphene dispersion 109, and keep stirring evenly. By adjusting the ratio of graphene concentration to mixed abrasive to 1:1, using ultrasonic oscillation or high shear emulsifier treatment, the interfacial force between graphene and mixed abrasive is further improved, and a multifunctional graphene composite nanoparticle abrasive 111 with a core-shell structure is obtained. A multifunctional graphene composite nanoparticle abrasive 111 having a core-shell structure is added to deionized water, the mass concentration of the abrasive is 2%, 0.5% polyvinyl pyrrolidone is added as a dispersant and 0.1% benzotriazole is added as a corrosion inhibitor, the ultrasonic equipment is set to a frequency of 35kHz and a power of 500W; the intensity of the electric field 103 is set to 3kV / cm;

[0054] 2. The device includes a polishing disc 13 containing a polishing liquid, an electrode 18 and an ultrasonic generator 1 are arranged on the polishing disc 13, two opposite flat plate electrodes 18 are installed on both sides of the polishing disc 13, the electrode 18 is made of stainless steel, and the size and shape are designed to fit the polishing disc 13, the ultrasonic generator 1 is fixed on the upper part of the polishing disc 13, and the ultrasonic probe on the ultrasonic generator 1 is in direct contact with the stainless steel plate workpiece 8;

[0055] 3. Fix the workpiece 8 in the center of the polishing disc 13, ensure that the surface of the workpiece 8 is in full contact with the polishing liquid, turn on the electric field 103 and the ultrasonic vibration wave 108, and continue polishing for 30 minutes. After polishing, use deionized water to clean the surface of the workpiece 8, and use an atomic force microscope (AFM) and an optical microscope to evaluate the surface roughness and microscopic morphology of the workpiece 8;

[0056] 4. After polishing, the surface roughness of the 304 stainless steel plate is reduced from Ra200nm before polishing to Ra10nm, and there are no obvious scratches and damage on the surface. The above polishing process is repeated 5 times, and the surface roughness of the workpiece 8 is stabilized at Ra10nm±0.5nm.

[0057] Example 2

[0058] The present invention is used for processing flat and thin parts of metal materials, metal alloy materials, etc., and a silicon wafer is selected as the polishing workpiece 8, with a size of 50mm×50mm×1mm. The processing steps are as follows:

[0059] 1. Fix the workpiece 8 on the polishing plate 13 of the experimental equipment using a fixture 7 or bonding resin;

[0060] 2. Prepare the composite polishing liquid 12, select the primary abrasive 110 made of 30 nanometer primary graphene sheets 101 and 200 nanometer silicon carbide (SiC) particles in a mass ratio of 2:1 through the dynamic high shear field-ultrasonic synergistic induction method, and slowly add the basic adsorbed graphene-nanoparticle abrasive to the second graphene dispersion 109, and keep stirring evenly. By adjusting the ratio of graphene concentration to mixed abrasive to 1:1, using ultrasonic oscillation or high shear emulsifier treatment, the interfacial force between graphene and mixed abrasive is further improved to obtain a multifunctional graphene composite nanoparticle abrasive 111 with a core-shell structure. The multifunctional graphene composite nanoparticle abrasive 111 with a core-shell structure is added to ethanol, the mass concentration of the abrasive is 3%, and 1% of silane coupling agent is added as a surfactant to improve the contact efficiency between the abrasive and the workpiece 8. The ultrasonic vibration wave 108 is set to a frequency of 40kHz and a power of 600W; the intensity of the electric field 103 is set to 4kV / cm;

[0061] 3. The device includes a heated polishing disc 13 with adjustable temperature, an electrode 18 and an ultrasonic generator 1 are arranged in the polishing disc 13, the electrode 18 is made of titanium alloy, is cylindrical in shape, and is installed on the side wall of the polishing disc 13, and the ultrasonic generator 1 is installed on the top of the polishing disc 13 through a movable arm, and the distance can be adjusted to adapt to workpieces 8 of different sizes;

[0062] 4. The workpiece 8 is exposed to the polishing liquid preheated to 35° C., fixed at the center of the polishing disc 13, the electric field 103 and the ultrasonic vibration wave 108 are started, the position of the ultrasonic generator 1 is adjusted to ensure that the wave evenly covers the surface of the workpiece 8, and the polishing is continued for 45 minutes. After the polishing is completed, the workpiece is cleaned with ethanol and the ultrasonic vibration wave 108, and then the uniformity and microscopic morphology of the surface of the workpiece 8 are checked using an electron microscope (SEM) and a 3D profilometer;

[0063] 5. After polishing, the surface roughness of the silicon wafer dropped from Ra10nm before polishing to Ra1.0nm, the surface quality was significantly improved, and there was no surface damage. The polishing test was repeated 10 times, and the results showed that the surface roughness of the workpiece was stable at Ra1.0nm±0.3nm.

[0064] Example 3

[0065] The present invention is used for efficient surface polishing, especially for the polishing of curved surfaces. A curved titanium alloy component with a complex geometric shape is selected as the polishing object. The maximum curvature radius of the component is 10 mm. The processing steps are as follows:

[0066] 1. Configuration, composite polishing liquid, selected from 50 nanometers of primary graphene sheet 101 and 100 nanometers of aluminum oxide (Al 2 O 3 ) The primary abrasive 110 is prepared by a dynamic high shear field-ultrasonic synergistic induction method with a mass ratio of 3:1, and the basic adsorbed graphene-nanoparticle abrasive is slowly added to the second graphene dispersion 109, and the stirring is kept uniform. By adjusting the ratio of the concentration of graphene to the mixed abrasive to 1:1, ultrasonic oscillation or high shear emulsifier treatment is used to further improve the interfacial force between the graphene and the mixed abrasive, and a multifunctional graphene composite nanoparticle abrasive 111 with a core-shell structure is obtained. The multifunctional graphene composite nanoparticle abrasive 111 with a core-shell structure is suspended in deionized water, the concentration of the abrasive is set to 4%, and 0.5% polyvinyl alcohol is added as a dispersant to enhance the dispersibility and stability of the abrasive;

[0067] 2. The device includes a polishing disc 13 equipped with a temperature control system. An electrode 18 and an ultrasonic generator 1 are installed in the polishing disc 13. The electrode 18 is made of stainless steel and is designed in a ring shape. It is arranged around the inner wall of the polishing disc. The ultrasonic generator 1 is installed on the top of the polishing disc 13. Its position can be fine-tuned to adapt to workpieces 8 with different curvatures.

[0068] 3. Fix the workpiece 8 on a specially designed fixture 7. The fixture 7 allows the workpiece 8 to rotate and tilt slightly during the polishing process to ensure the uniformity of the polishing. The temperature of the polishing plate 13 is maintained at 40° C. The electric field 103 and the ultrasonic vibration wave 108 are started. The polishing time is 60 minutes. After the polishing is completed, the workpiece 8 is cleaned in high-pressure deionized water, and then the surface roughness and morphology are evaluated using an atomic force microscope (AFM) and a white light interferometer.

[0069] 4. After polishing, the surface roughness of the titanium alloy parts was reduced from Ra10nm before polishing to Ra5nm, which effectively improved the surface finish and reduced micro damage. After 5 consecutive polishing tests with the same parameters, the standard deviation of the surface roughness measurement value did not exceed 0.2nm, indicating that the polishing method has good repeatability and stability.

[0070] In the present invention, a graphene composite nanoparticle abrasive flexible fluid electric field 103-ultrasound assisted 108 polishing method and device, when used, the working process is as follows:

[0071] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7As shown, the electrode 18 is installed on the top of the frame 14 to ensure that the electrode 18 maintains an appropriate distance from the surface of the workpiece 8 to be polished and can cover the entire polishing area. The power supply is electrically connected to the electrode 18 to provide the required electric field 103 strength and voltage. The power supply voltage and frequency are adjusted according to the needs. The electric field 103 strength, direction and duration of the electric field 103 are adjusted by the controller. In the process of applying the electric field 103, the corresponding monitoring equipment is used to monitor the intensity and distribution of the electric field 103 in real time to ensure its stability and accuracy. Under the stimulation of the ultrasonic vibration wave 108, the nanoparticles 102 and graphene 101 bombard the surface of the workpiece 8, causing debris 104 to form on the surface of the workpiece 8. While polishing, the electric field 103 is applied to ensure that the electric field 103 and the ultrasonic assisted technology are synchronized with the polishing process to maximize the polishing effect. Under the action of the ultrasonic vibration wave 108, the cavitation bubbles 107 formed in the polishing liquid have a thickening rheological effect on the polishing liquid, and the nano-abrasive particles therein generate tiny jets to shear and remove excess material on the surface of the workpiece 8. Before the electric field 103 is applied, the abrasive particles and the primary graphene 101 and the secondary graphene 109 in the polishing liquid are continuously and evenly distributed. When the electric field 103 is applied, the microstructure of the polishing liquid changes. Under the action of the external electric field 103, the solid phase particles in the polishing liquid are polarized and form particle chains along the direction of the electric field 103, wherein the abrasive particles required for polishing are combined in the particle chains. Before the electric field 103 is applied, the abrasive particles are free between the polishing head 6 and the workpiece 8. When the electric field 103 is applied, the abrasive particles are free between the polishing head 6 and the workpiece 8. 03, the polarized particles are concentrated between the dispersed phase particles and the surface of the workpiece 8. When the polishing head 6 moves relatively, the primary graphene 101 and the secondary graphene 109 in the polishing liquid drive the abrasive particles to shear and collide with the surface of the workpiece 8, thereby removing the excess material on the surface of the workpiece 8. At the same time, the cavitation bubbles 107 carry the nanoparticles 102 and the primary graphene 101 and the secondary graphene 109, and release the impactful double graphene and nanoparticles 102 when they collapse, bombarding or scratching the surface of the workpiece 8, thereby removing the surface material.

[0072] 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. A graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method, characterized in that: The method comprises the following steps: S1. Firstly, chemical bonding and graft copolymerization of primary graphene and nanoparticles are achieved by a dynamic high shear field-ultrasound synergistic induction method, and then the primary abrasive and secondary graphene are composited into a graphene composite nanoparticle abrasive having a multilayer structured coating system with a core-shell structure by a dynamic high shear field-ultrasound synergistic induction method; S2, applying an electric field during the polishing process through electrodes, a power supply and a controller in the electric field application component, a polishing component and an infusion component to adjust the arrangement and movement of particles on the surface; S3, using an ultrasonic auxiliary component to apply ultrasonic waves during polishing to improve the contact between particles and the surface and remove surface defects; S4. Track the microscopic state of the abrasive particles and the surface state of the workpiece during polishing.

2. The graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method according to claim 1, characterized in that: In step S1, the nanoparticles are one or a mixture of two or more of metal oxides, carbides or borides, the proportion of graphene is 10% to 50% by weight, the particle size of the nanoparticles is in the range of 10-100 nanometers, the dynamic high shear field-ultrasound synergistic induction method is to process in a high shear homogenizer, use high-speed fluid movement to form strong shear force and eddy current action, so that the nanoparticles are evenly embedded in the graphene flakes, turn on the ultrasonic device, and combine the high shear shear force to promote the graphene flakes to form a multi-layer coating structure on the surface of the abrasive, the multi-layer coating structure is incompletely coated and contains a cutting exposed area; the graphene and Nanoparticles use dynamic high shear field and ultrasonic synergistic induction technology, utilize the high shear force of the fluid and ultrasonic cavitation, to achieve precise compounding of graphene and nanoparticles in the process of multi-level dispersion, dynamic reorganization and multi-layer coating. The new composite abrasive is a multifunctional graphene composite nanoparticle abrasive with a core-shell structure. Its hard core provides high strength and wear resistance, and the graphene shell gives it multiple excellent properties such as conductivity, thermal conductivity, self-lubrication and anti-agglomeration. The primary graphene is single-layer graphene, multi-layer graphene or graphene oxide, and the secondary graphene is graphene with different modification methods, including graphene oxide or reduced graphene oxide.

3. The graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method according to claim 1 or 2, characterized in that: In step S2, the electric field applying component includes an electrode and a power supply and a controller electrically connected thereto, and the controller is used to monitor and adjust the electric field strength, ultrasonic frequency, amplitude and working cycle, as well as polishing pressure and time in real time. The electric field and ultrasonic waves are used for microstructure regulation, and the microstructure regulation controls the distribution density, size and morphology of graphene and nanoparticle abrasives by adjusting the parameters of the electric field and ultrasonic treatment.

4. The graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method according to claim 3, characterized in that: The controller automatically adjusts electric field parameters and ultrasonic parameters according to the conductivity, hardness and surface roughness of the workpiece material through sensor input.

5. The graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method according to claim 1 or 2, characterized in that: In step S3, the ultrasonic auxiliary component includes an ultrasonic generator, an ultrasonic transducer, a horn and a sensor, and the ultrasonic generator is used to emit ultrasonic waves with adjustable ultrasonic frequency and amplitude to the polishing liquid.

6. The graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method according to claim 1 or 2, characterized in that: In step S2, the polishing assembly includes a polishing head, a fixture, a workpiece, a polishing pad, a polishing disc and a frame, wherein the frame is used to support and carry the polishing disc, the fixture, the ultrasonic auxiliary component, the electric field application component and the infusion component, the polishing head is used to polish the workpiece, and the polishing disc is used to hold the polishing liquid and the workpiece.

7. The graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method according to claim 1 or 2, characterized in that: In step S2, the infusion assembly includes a catheter, a hydraulic pump and a box, the box is used to store the prepared polishing liquid, and the hydraulic pump is used to extract the polishing liquid in the box and transport it to the polishing plate through the catheter.

8. A device for implementing the graphene composite nanoparticle abrasive flexible fluid electric field-ultrasound assisted polishing method as claimed in claim 1, characterized in that: The device includes an electric field applying component, an ultrasonic auxiliary component, a polishing component and an infusion component. The polishing component includes a polishing head, a fixture, a polishing disc and a frame. The frame is used to support and carry the polishing disc, the fixture, the ultrasonic auxiliary component, the electric field applying component and the infusion component. The polishing head is used to polish the workpiece, and the polishing disc is used to contain polishing liquid and the workpiece. The polishing head is located above the polishing disc, the ultrasonic auxiliary component is located above the polishing disc, the electric field applying component is located on the side of the polishing disc, and the liquid guide tube outlet of the infusion component is aligned with the polishing head and the processing station of the workpiece.

9. The device according to claim 8, characterized in that The electric field applying component includes an electrode and a power supply and a controller electrically connected thereto. The controller is used to monitor and adjust the electric field intensity, ultrasonic frequency, amplitude and working cycle, as well as polishing pressure and time in real time. The electric field and ultrasonic waves are used for microstructure regulation, and the microstructure regulation controls the distribution density, size and morphology of graphene and nanoparticle abrasives by adjusting the parameters of the electric field and ultrasonic treatment.

10. The device according to claim 8 or 9, characterized in that The ultrasonic auxiliary component comprises an ultrasonic generator, an ultrasonic transducer, a horn and a sensor, wherein the ultrasonic generator is used to emit ultrasonic waves with adjustable ultrasonic frequency and amplitude to the polishing liquid, the ultrasonic generator is installed on the top of the polishing disc through a movable arm, and the distance can be adjusted to adapt to workpieces of different sizes, the ultrasonic generator is connected to the ultrasonic transducer, the ultrasonic transducer is connected to the horn, the polishing head is installed at the bottom of the horn, and the sensor is installed on the frame; The infusion assembly comprises a liquid guide tube, a hydraulic pump and a box body. The box body is used to store the prepared polishing liquid. The hydraulic pump is used to extract the polishing liquid in the box body and transport it to the polishing plate through the liquid guide tube.

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