Plasma-assisted micro-grit jet polishing machining device and method

Abstract

The application discloses a kind of plasma assisted micro abrasive grain jet polishing processing manufacturing device, including plasma generation system, micro abrasive grain jet system and auxiliary processing system, the loading tray of auxiliary processing system is installed in the side of workpiece converter, the shaft of loading tray is equipped with rotating shaft, rotating shaft is transitionally cooperated with rotator, rotating speed control box controls rotating speed of rotating shaft by wire;The upper end of connecting frame is installed tool converter, and the left and right ends of connecting frame are connected with air suction pump respectively through conduit, and the bottom of conduit is connected into collection chamber, and the lower end of connecting frame is installed in the upper end of workpiece inner hole;Plasma generation system, micro abrasive grain jet system are all located above tool converter, and micro abrasive grain jet system is installed on loading tray, and plasma generation system is installed on the other side of workpiece converter.And provide a kind of plasma assisted micro abrasive grain jet polishing processing manufacturing method.The application is easy to chip, higher finishing surface shape precision, and processing controllability is high.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of atomic near-atomic scale ultra-precision polishing, and particularly relates to a plasma-assisted micro abrasive jet polishing manufacturing device and method. BACKGROUND

[0002] Due to space structure restrictions or thrust-to-weight ratio requirements, blind holes are widely used in integrated circuits, hydraulic systems, automobiles and other fields, such as positioning pin holes (blind holes) for dynamic balancing in rotating objects, and used as piston cylinders in hydraulic systems and internal combustion engines. However, the finishing machining of the inner surface of the blind hole is more difficult, especially the machining of the bottom edge, and domestic and foreign researchers have less research on blind holes, which makes the subsequent precision machining of the blind hole an important machining problem in China. Most of the domestic inner surface finishing machining of pipes is carried out by chemical polishing, however, chemical processing liquid is easy to pollute the environment. Ultra-precision grinding and polishing is a near / no damage machining manufacturing technology that does not change the physical properties of the workpiece material, removes surface burrs, damage layer and other defects, and improves the surface precision and integrity of the workpiece, which is often used for high-performance manufacturing of difficult-to-machine materials such as semiconductors, optical elements, functional ceramics and plastic material parts.

[0003] Plasma-assisted polishing is a surface treatment technology in which plasma interacts with the material surface to improve the smoothness and quality of the material surface through chemical reactions and physical effects. The process is usually carried out in a vacuum or atmosphere-controlled environment using a radio frequency plasma source to generate plasma. The charged particles in the plasma chemically react with the material surface to remove surface defects, oxides, organic contaminants or micro-roughness, etc., thereby achieving nanoscale flattening and microstructure control of the surface. Plasma-assisted polishing is different from traditional mechanical polishing methods. Traditional mechanical polishing mainly relies on mechanical force and abrasive to remove defects and roughness on the surface of the material, while plasma-assisted polishing utilizes the interaction of plasma with the material surface to improve the surface quality.

[0004] In order to meet the polishing needs of different types of hard and brittle difficult-to-machine materials, ultra-precision machining by abrasive jet surface has appeared. Micro abrasive jet machining is a method that can effectively solve the machining problem of hard and brittle materials. Its working principle is that through the mixing of micro abrasive and high-pressure gas, after special design of the nozzle, the micro abrasive is accelerated and shot to the workpiece material, and the abrasive is used to realize the removal of the material by the scouring and polishing effect.

[0005] The invention discloses a kind of special-shaped blind cavity workpiece precision polishing device and polishing method, including: core, including installation section and cooperation section, cooperation section outer wall shape is matched with the shape of workpiece inner cavity and is set with preset proportion, it is inserted into inner cavity and with inner cavity surface has gap;Core is set with flow guide hole, for the polishing medium is passed through and fills the gap between cooperation section and inner cavity;Cooperation section is set with recovery hole, for the polishing medium is passed through and then exports polishing medium;Box;Fixed system, for fixed core and workpiece;Ultrasonic generating system, for providing ultrasonic vibration according to set frequency.Based on this polishing device, special-shaped blind cavity workpiece can be simultaneously applied to abrasive grain flow polishing and ultrasonic polishing, solve the problem that abrasive or polishing liquid cannot pass through blind hole directly, further avoid using five-axis machine tool installation abrasive head setting route and polish, greatly reduce labor cost, processing cost, effectively improve processing efficiency.However, the patent does not involve plasma-assisted polishing mechanism, and the atomic near-atomic scale ultra-precision polishing quality of workpiece can be further improved.

[0006] The invention discloses a kind of method and device of plasma polishing workpiece, the method of plasma polishing workpiece includes the following steps: the workpiece to be polished is placed on the workpiece frame in polishing vacuum chamber, and the polishing vacuum chamber is evacuated;Inert gas is introduced into the vacuum chamber until the gas pressure in the vacuum chamber reaches the set value;The workpiece to be polished is heated by plasma;After completing plasma heating, fluorine-containing gas is introduced into the vacuum chamber until the gas pressure in the vacuum chamber reaches the set value;The ion source is opened, the grid is powered on, and the workpiece to be polished is immersed in the plasma for polishing;The ion source is closed, and the grid is powered off, i.e. the polishing of the workpiece is completed;Through the effective cooperation of ion source, high-frequency electric field, electromagnetic field and grid, the effective control of plasma is realized, and immersion polishing is realized;The invention can realize the shape retention of plasma on workpiece, realize the polishing of complex shape surface and flat surface.However, the patent does not involve micro-abrasive jet polishing, and there is still room for improvement in efficient polishing of workpiece.

[0007] The invention discloses a kind of method for processing silicon-based element by magnetorheological auxiliary atmospheric plasma polishing, to solve the problem that surface residue is generated when existing atmospheric plasma is processed, which causes the surface quality of optical element to be seriously reduced.First, use atmospheric plasma to process silicon-based element with He as carrier gas, CF4 As reaction gas and O2 As auxiliary gas, generate residue, then polish the surface of element by magnetorheological, the generated residue is quickly removed by flexible abrasive in magnetorheological fluid, realize high-efficiency polishing of silicon-based optical element. SUMMARY

[0008] In order to overcome the shortcomings of the prior art, in order to solve the problems of high-quality material removal, low polishing precision of the inner hole wall of the workpiece, and difficult removal of blind hole machining chips, the application provides a plasma-assisted micro abrasive jet polishing machining device and method, which has high polishing efficiency and can achieve atomic or near-atomic scale polishing precision.

[0009] The application solves the technical problems by adopting the following technical solutions:

[0010] A plasma-assisted micro abrasive jet polishing machining device, the device comprises a plasma generation system, a micro abrasive jet system and an auxiliary machining system, the auxiliary machining system comprises a rotating speed control box, a rotator, a rotating shaft, a tool changer, a loading disc, a connecting frame, a suction pump and a collection chamber, the loading disc is installed on one side of the workpiece changer, the rotating shaft is arranged at the center of the loading disc, the rotating shaft is in transition fit with the rotator, and the rotating speed control box controls the rotating speed of the rotating shaft through wires; the tool changer is installed at the upper end of the connecting frame, the left and right ends of the connecting frame are connected with the suction pump through pipes respectively, the bottom of the pipe is connected with the collection chamber, and the lower end of the connecting frame is installed on the upper end of the inner hole of the workpiece and forms a closed space required for machining with the inner hole of the workpiece; the plasma generation system and the micro abrasive jet system are located above the tool changer, the micro abrasive jet system is installed on the loading disc, and the plasma generation system is installed on the other side of the workpiece changer.

[0011] Further, the rotating shaft and the guide rail are installed on the loading disc, the rotating shaft is connected with the rotator, and the required power is provided for micro abrasive jet machining; the micro abrasive jet system is connected with the guide rail of the loading disc, the guide rail is distributed along the radius of the loading disc, and is used for adjusting the machining radius so as to adapt to the inner holes of workpieces of different sizes.

[0012] Preferably, a protective film is covered on the surface of the workpiece in the machining area, the protective film protects the surface of the workpiece and prevents the surface of the workpiece from being oxidized by the plasma and abraded by the micro abrasive.

[0013] The plasma generating system comprises a gas supply module, a radiation power supply module and a plasma excitation module, wherein the gas supplied by the gas supply module comprises cooling gas, reaction gas and inert gas, the plasma excitation module comprises a plasma torch pipe, a resistance matching device, an induction coil and an electric spark generator, the right side of the gas supply tank of the gas supply module is connected with the cooling gas, the reaction gas and the inert gas through conduits respectively, wherein the inert gas and the reaction gas are mixed in the gas supply tank and then flow out from the internal pipeline of the plasma torch pipe through the conduits, and the cooling gas flows out from the external pipeline of the plasma torch pipe alone; the plasma torch pipe is arranged above the tool converter and is installed in cooperation with the left side of the tool converter, the induction coil is arranged around the bottom of the plasma torch pipe, the positive pole of the radio frequency power supply of the radiation power supply module is connected to one end of the induction coil through the impedance matching device, the negative pole of the radio frequency power supply and the other end of the induction coil are grounded, and the electric spark generator is located in the internal pipeline of the plasma torch pipe.

[0014] The micro abrasive particle spraying system comprises an abrasive particle supply module and a nozzle module, wherein the abrasive particle supply module comprises an air compressor, an abrasive particle storage chamber and a conduit, and the nozzle module comprises a nozzle body, a connecting cap and a nozzle; the upper left end of the abrasive particle storage chamber is connected with the air compressor, the lower right end of the abrasive particle storage chamber is connected with the nozzle module through the conduit, one end of the connecting cap of the nozzle module is matched with the nozzle body, the other end of the connecting cap is matched with the nozzle, the nozzle body is connected with the conduit, and the connecting cap is connected with the guide rail of the loading disc.

[0015] Further, the abrasive particle supply module further comprises a flow control valve, and the flow control valve is arranged in the interior of the abrasive particle storage chamber; the abrasive particle supply module adopts flow limiting type feeding, and in the process of micro abrasive particle spraying machining, the flow control valve is opened, and under the auxiliary action of high-speed airflow, the micro abrasive particles can be accelerated to be sprayed out.

[0016] Still further, the nozzle of the nozzle module adopts a conical nozzle, and the cone shape is mainly for flow guiding and accelerating particles; since the conical nozzle is compressed, the abrasive particles are more easily sucked in, and since the particles are gathered in the straight section, the sprayed particle beam is more concentrated, which is beneficial to efficient material removal.

[0017] The cooling gas is helium or argon; the reaction gas is oxygen or water vapor; and the inert gas is helium or argon.

[0018] The micro abrasive particles comprise one or at least two or more of a mixture of nanodiamond, boron carbide, silicon carbide, silicon nitride, silicon oxide, gallium oxide and aluminum oxide.

[0019] The free radicals in the plasma have strong oxidizing property, chemically react with atoms on the inner hole surface of the workpiece, and form a denatured layer with low hardness.

[0020] A kind of plasma assisted micro abrasive jet polishing processing manufacturing method, using plasma assisted oxidation workpiece material to form soft denaturation layer, and then removing denaturation layer by micro abrasive jet, the method comprises the following steps:

[0021] (1) the connecting frame is fixed on workpiece, it needs to ensure that the center hole of connecting frame is coaxial with the blind hole of workpiece, and the surface of workpiece is covered with protective film in processing area;

[0022] (2) start the air suction pump, let the connecting frame inner chamber be in vacuum state, then close the air suction pump;

[0023] (3) control tool converter to adjust to plasma generation system;

[0024] (4) start gas supply tank, let reaction gas and inert gas pass into the inner cavity of plasma torch pipe, and cooling gas passes into the outer cavity of plasma torch pipe;

[0025] (5) start radio frequency power supply and electric spark generator, make inert gas ionize by electric spark igniter, high-frequency current generated by radio frequency power supply flows into coil and generates high-frequency induction magnetic field, and reaction gas is excited to generate plasma;

[0026] (6) control tool converter to adjust to micro abrasive jet system;

[0027] (7) adjust nozzle module, so that its jet point is aligned with the inner hole wall of workpiece;

[0028] (8) start air compressor, flow control valve and speed control box at the same time, and nozzle module carries out circumferential shearing impact micro-removal to the denaturation layer of the inner hole wall of workpiece;

[0029] (9) close flow control valve and open air suction pump, use high-speed airflow to blow abrasive particles and chips in the inner hole of workpiece into both sides of connecting frame inner chamber, and then recycle to collection chamber by air suction pump;

[0030] (10) repeat steps (2)-(9) for 2-3 times, and adjust the repetition period of the above steps according to actual workpiece processing process parameter index requirements;

[0031] (11) close all switches, disassemble the connecting frame, and complete processing.

[0032] Further, in the step (1), the protective film plays a protective role on the surface of workpiece, to prevent the surface of workpiece from being oxidized by plasma and abraded by micro abrasive.

[0033] The beneficial effects of the present application mainly include:

[0034] 1) Easy chip removal. During the polishing process, chips are generated and accumulate, affecting surface processing accuracy. The present invention uses fine abrasive jet technology to remove chips. During the processing, high-speed airflow is used to blow the chips in the hole into the inner chamber of the connecting frame. Then, an air suction pump is used to suck the chips in the inner chamber of the connecting frame into the collection chamber. This can effectively remove the chips in a timely manner, keeping the workpiece surface clean and ensuring the polishing process.

[0035] 2) High surface finishing accuracy. This invention uses plasma-assisted polishing technology, leveraging the strong oxidizing properties of free radicals in the plasma to chemically react with atoms on the surface of the workpiece's inner hole, forming a modified layer with lower hardness. Fine abrasive jetting technology is then used to vertically remove material, significantly improving surface accuracy.

[0036] 3) High controllability. Micro-abrasive machining involves sharp abrasive particles eroding the material, resulting in a high number of effective cutting edges. The amount of material removed can be controlled by factors such as gas pressure and abrasive size. This allows for high efficiency in localized machining, while reducing the removal rate of soft and tough materials.

[0037] 4) Wide processing range. A rotating shaft and guide rails are mounted on the loading plate. The rotating shaft is connected to the rotor, providing the necessary power for micro-abrasive jet machining. The guide rails are distributed along the radius of the loading plate, and nozzle modules are mounted on the guide rails to adjust the processing radius to accommodate workpiece bores of varying sizes.

[0038] 5) The present invention has relatively low requirements on processing equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Fig. 1 Schematic diagram of the plasma-assisted micro-abrasive jet polishing manufacturing device.

[0040] Fig. 2 Schematic diagram of the processing principle of plasma-assisted micro-abrasive jet polishing manufacturing device.

[0041] Fig. 3 Schematic diagram of microscopic material removal in plasma-assisted micro-abrasive jet polishing manufacturing equipment.

[0042] Fig. 4 Schematic diagram of the nozzle module of the plasma-assisted micro-abrasive jet polishing manufacturing device.

[0043] Fig. 5 Schematic diagram of the loading plate of the plasma-assisted micro-abrasive jet polishing manufacturing device.

[0044] Fig. 6 Schematic diagram of the loading plate rotation assistance in the plasma-assisted micro-abrasive jet polishing manufacturing device.

[0045] Wherein, 1, gas supply tank; 2, plasma torch pipe; 3, spark generator; 4, RF power supply; 5, resistance matching device; 6, induction coil; 7, air compressor; 8, abrasive grain storage chamber; 9, flow control valve; 10, conduit; 11, nozzle body; 12, connecting cap; 13, nozzle; 14, tool changer; 15, loading disc; 16, rotating shaft; 17, rotator; 18, rotating speed control box; 19, guide rail; 20, connecting frame; 21, suction pump; 22, collection chamber; 23, workpiece; 101, high-speed airflow; 102, nozzle module; 201, workpiece hole inner wall; 202, denatured layer; 203, plasma oxidation; 204, micro abrasive grain jet removal; 301, micro abrasive grain; 302, shearing impact; 303, debris; 401, cooling gas; 402, reaction gas; 403, inert gas. DETAILED DESCRIPTION

[0046] The application will be further described below with reference to the accompanying drawings.

[0047] Reference Figs. 1-6 A plasma-assisted micro abrasive grain jet polishing machining device, comprising a plasma generation system, a micro abrasive grain jet system and an auxiliary machining system, the plasma generation system comprises a gas supply module, a radiation power supply module and a plasma excitation module, wherein the gas supplied by the gas supply module comprises cooling gas 401, reaction gas 402 and inert gas 403, the plasma excitation module comprises plasma torch pipe 2, resistance matching device 5, induction coil 6 and spark generator 3, the right side of the gas supply tank 1 of the gas supply module is connected with the cooling gas 401, the reaction gas 402 and the inert gas 403 through the conduit 10 respectively, wherein the inert gas 403 and the reaction gas 402 flow out from the internal pipeline of the plasma torch pipe 2 after being mixed in the supply tank through the conduit 10, and the cooling gas 401 flows out from the external pipeline of the plasma torch pipe 2 alone; the plasma torch pipe 2 is arranged above the tool changer 14 and is installed in cooperation with the left side of the tool changer 14, the induction coil 6 surrounds the bottom of the plasma torch pipe 2, the positive electrode of the RF power supply 4 of the radiation power supply module is connected to one end of the induction coil 6 through the impedance matching device, the negative electrode of the RF power supply 4 and the other end of the induction coil 6 are both grounded, and the spark generator 3 is located in the internal pipeline of the plasma torch pipe 2;

[0048] Optionally, the plasma torch tube 2 is a key component of the plasma pre-treatment device, which adopts a coaxial design and is composed of an inner and outer glass tube. During operation, the inner tube injects inert gas 403 and reactive gas 402, which are used to excite and maintain the active particles required for the oxidation process; the inert gas 403 in the plasma torch tube 2 is ignited to form a stable plasma environment. The outer tube injects a large amount of cooling gas 401 to carry away the heat energy transferred by the plasma core, which helps to reduce the working temperature of the torch tube and prevent the glass tube from bursting or melting due to excessive temperature. With the excitation of the spark, the inert gas 403 is gradually activated in the torch tube to form a weak plasma. During operation, the spark ignition device is used to ignite and ionize the inert gas 403; the 13.56 MHz RF power source 4 is combined with the iron coil around the torch tube to form a high-frequency electromagnetic field inside the torch tube. Under the action of the electric field, the ionized gas collides strongly with the un-ionized gas in rapid movement, which causes the gas to continue to ionize, so that the reactive gas 402 is excited or dissociated to form active groups with strong oxidation ability for surface oxidation treatment.

[0049] The micro-abrasive blasting system comprises an abrasive supply module and a nozzle module 102, wherein the abrasive supply module comprises an air compressor 7, an abrasive storage chamber 8, a flow control valve 9 and a conduit 10, and the nozzle module 102 comprises a nozzle body 11, a connecting cap 12 and a nozzle 13; the upper left end of the abrasive storage chamber 8 is connected with the air compressor 7, the lower right end of the abrasive storage chamber 8 is connected with the nozzle module through the conduit 10, and the flow control valve 9 is arranged in the abrasive storage chamber 8; one end of the connecting cap 12 of the nozzle module 102 is matched with the nozzle body 11, the other end of the connecting cap 12 is matched with the nozzle 13, the nozzle body 11 is connected with the conduit 10, and the connecting cap 12 is connected with the guide rail 19 of the loading disc 15;

[0050] Optionally, the abrasive supply module adopts a flow-limiting supply mode, and during the micro-abrasive blasting process, the flow control valve 9 is opened, and under the auxiliary action of high-speed airflow, the micro-abrasive particles can be accelerated and ejected.

[0051] Optionally, the nozzle 13 of the nozzle module 102 adopts a conical nozzle, and the cone shape is mainly for flow guiding and accelerating particles. Since it is compressed, the abrasive is more easily sucked in, and due to the gathering effect of the flat section, the ejected particle beam is more concentrated, which is beneficial to efficient material removal.

[0052] The auxiliary processing system comprises a rotating speed control box 18, a rotator 17, a rotating shaft 16, a tool changer 14, a loading disc 15, a connecting frame 20, a suction pump 21 and a collection chamber 22, the loading disc 15 is installed on the left side of the tool changer 14, the rotating shaft 16 is arranged at the shaft center of the loading disc 15, the rotating shaft 16 is transitionally matched with the rotator 17, and the rotating speed control box 18 controls the rotating speed of the rotating shaft 16 through wires; the tool changer 14 is installed at the upper end of the connecting frame 20, the connecting frame 20 is connected with the suction pump 21 through pipes at the left and right ends respectively, the pipes at the bottom are connected into the collection chamber 22, and the lower end of the connecting frame 20 is installed at the upper end of the inner hole of the workpiece 23, and forms a closed space required for processing with the inner hole of the workpiece 23.

[0053] Optionally, the rotating shaft 16 and a guide rail 19 are installed on the loading disc 15, the rotating shaft 16 is connected with the rotator 17, and provides the required power for the micro abrasive jet processing. The guide rail 19 is distributed along the radius of the loading disc 15, and a nozzle module is installed on the guide rail 19, which is used for adjusting the processing radius so as to adapt to the inner holes of workpieces 23 of different sizes.

[0054] Optionally, a protective film is covered on the surface of the workpiece in the processing area, and the protective film protects the surface of the workpiece and prevents the surface of the workpiece from being oxidized by plasma and abraded by micro abrasive.

[0055] The free radicals in the plasma have strong oxidizing property, and chemically react with atoms on the surface of the inner hole of the workpiece to form a denatured layer with low hardness.

[0056] The method can greatly improve the polishing efficiency and achieve atomic near-atomic scale polishing precision.

[0057] The polishing processing method comprises the following steps:

[0058] The connecting frame 20 is fixed on the workpiece, and the center hole of the connecting frame 20 needs to be coaxial with the blind hole of the workpiece 23, and a protective film is covered on the surface of the workpiece in the processing area.

[0059] The suction pump 21 is started, and the inner chamber of the connecting frame 20 is in a vacuum state, and then the suction pump 21 is closed.

[0060] The tool changer 14 is controlled to be adjusted to the plasma generating system.

[0061] The gas supply box 1 is started, the reaction gas 402 and the inert gas 403 are introduced into the inner cavity of the plasma torch pipe 2, and the cooling gas 401 is introduced into the outer cavity of the plasma torch pipe 2.

[0062] Start the radio frequency power supply 4 and the electric spark generator 3, and ignite the inert gas 403 by the electric spark igniter; the high-frequency current generated by the radio frequency power supply 4 flows into the coil to generate a high-frequency induction magnetic field, and the reaction gas 402 is excited to generate plasma.

[0063] The control tool converter 14 is adjusted to the micro-grit spraying system.

[0064] The nozzle module is adjusted so that the spraying point is aligned with the inner hole wall of the workpiece 23.

[0065] The air compressor 7, the flow control valve 9 and the rotating speed control box 18 are started at the same time, and the nozzle module performs circumferential shearing impact micro-removal on the modified layer of the inner hole wall of the workpiece 23.

[0066] The flow control valve 9 is closed and the air suction pump 21 is opened, and the abrasive grains and cutting chips in the inner hole of the workpiece 23 are blown into the inner chamber of the connecting frame 20 under the auxiliary action of the high-speed airflow, and then are recovered to the collection chamber 22 through the air suction pump 21.

[0067] The steps 2) to 9) are repeated for 2 to 3 times, and the repetition period of the above steps is adjusted according to the actual workpiece processing process parameter index requirements.

[0068] All switches are closed, and the connecting frame 20 is disassembled, and the processing is completed.

[0069] Example 1

[0070] The present application is used for processing a workpiece 23 blind hole (silicon material, optical crystal, glass, functional ceramic and various difficult-to-machine materials) with a size of 30 mm in diameter and 90 mm in length.

[0071] The polishing method comprises the following steps:

[0072] The connecting frame 20 is fixed on the blind hole workpiece 23 with a diameter of 3 mm and a length of 90 mm, and the center hole of the connecting frame 20 needs to be coaxial with the blind hole of the workpiece 23, and the workpiece surface in the processing area is covered with a protective film.

[0073] The air suction pump 21 is started, and the inner chamber of the connecting frame 20 is in a vacuum state, and then the air suction pump 21 is closed.

[0074] The control tool converter 14 is adjusted to the plasma generation system.

[0075] The gas supply box 1 is started, and the reaction gas 402 and the inert gas 403 are introduced into the inner cavity of the plasma torch pipe 2, and the cooling gas 401 is introduced into the outer cavity of the plasma torch pipe 2.

[0076] Start the radio frequency power supply 4 and the electric spark generator 3, and ignite the inert gas 403 by the electric spark igniter. The high-frequency current generated by the radio frequency power supply 4 flows into the coil to generate a high-frequency induction magnetic field, and the reaction gas 402 is excited to generate plasma.

[0077] The control tool converter 14 is adjusted to the micro-grit spraying system.

[0078] The nozzle module is adjusted so that the spraying point is aligned with the inner wall of the blind hole of the workpiece 23.

[0079] The air compressor 7, the flow control valve 9 and the rotating speed control box 18 are started at the same time, and the nozzle module performs circumferential shearing impact micro-removal on the modified layer of the inner wall of the blind hole of the workpiece 23.

[0080] The flow control valve 9 is closed and the air suction pump 21 is opened, and the abrasive grains and chips in the blind hole of the workpiece 23 are blown into the inner chamber of the connecting frame 20 on both sides, and then are recovered to the collection chamber 22 through the air suction pump 21.

[0081] The steps 2) to 9) are repeated 2 to 3 times, and the repetition period of the above steps is adjusted according to the actual workpiece processing process parameter index requirements.

[0082] All switches are closed, and the connecting frame 20 is disassembled, and the processing is completed.

[0083] Example 2

[0084] The application is used for processing a through hole of the workpiece 23 with a size of a diameter of 30 mm and a length of 90 mm (silicon material, optical crystal, glass, functional ceramic and various difficult-to-machine materials).

[0085] The polishing method comprises the following steps:

[0086] A sealing element is installed on the bottom surface of the through hole workpiece 23 with a diameter of 3 mm and a length of 90 mm.

[0087] The connecting frame 20 is fixed on the through hole workpiece 23, and the center hole of the connecting frame 20 needs to be coaxial with the through hole of the workpiece 23, and a protective film is covered on the surface of the workpiece in the processing area.

[0088] The air suction pump 21 is started, and the inner chamber of the connecting frame 20 is in a vacuum state, and then the air suction pump 21 is closed.

[0089] The control tool converter 14 is adjusted to the plasma generation system.

[0090] The gas supply box 1 is started, and the reaction gas 402 and the inert gas 403 are introduced into the inner cavity of the plasma torch pipe 2, and the cooling gas 401 is introduced into the outer cavity of the plasma torch pipe 2.

[0091] The radio frequency power source 4 and the electric spark generator 3 are started, the inert gas 403 is ignited and ionized by the electric spark igniter, the high frequency current generated by the radio frequency power source 4 flows into the coil to generate a high frequency induction magnetic field, and the reaction gas 402 is excited to generate plasma.

[0092] The control tool converter 14 is adjusted to the fine abrasive particle spraying system.

[0093] The nozzle module is adjusted so that the spraying point is aligned with the inner wall of the through hole 23 of the workpiece.

[0094] The air compressor 7, the flow control valve 9 and the rotating speed control box 18 are started at the same time, and the nozzle module performs circumferential shearing impact micro-removal on the modified layer of the inner wall of the through hole of the workpiece 23.

[0095] The flow control valve 9 is closed and the air suction pump 21 is opened, the abrasive particles and the cutting chips in the through hole of the workpiece 23 are blown into the inner chamber of the connecting frame 20 on both sides by the high-speed airflow, and then are recovered to the collection chamber 22 by the air suction pump 21.

[0096] The steps 3) to 10) are repeated 2 to 3 times, and the repetition period of the above steps is adjusted according to the actual workpiece processing process parameter index requirements.

[0097] All switches are closed, and the connecting frame 20 is disassembled, and the processing is completed.

[0098] The content described in the embodiments of the present specification is only a list of implementation forms of the inventive concept, and is only for the purpose of description. The protection scope of the present application should not be regarded as being limited to the specific forms described in the embodiments, and the protection scope of the present application also extends to the equivalent technical means that can be thought of by those skilled in the art according to the inventive concept.

Claims

1. A plasma-assisted fine abrasive jet polishing manufacturing device, characterized in that: The device comprises a plasma generating system, a micro abrasive particle spraying system and an auxiliary machining system, the auxiliary machining system comprises a rotating speed control box, a rotator, a rotating shaft, a tool changer, a loading disc, a connecting frame, a suction pump and a collection chamber, the loading disc is installed on one side of the workpiece changer, a rotating shaft is arranged at the center of the loading disc, the rotating shaft is in transition fit with the rotator, and the rotating speed control box controls the rotating speed of the rotating shaft through wires; the tool changer is installed at the upper end of the connecting frame, the left and right ends of the connecting frame are connected with the suction pump through pipes respectively, the pipes at the bottom lead into the collection chamber, and the lower end of the connecting frame is installed at the upper end of the inner hole of the workpiece and forms a closed space required for machining with the inner hole of the workpiece; the plasma generating system and the micro abrasive particle spraying system are located above the tool changer, the micro abrasive particle spraying system is installed on the loading disc, and the plasma generating system is installed on the other side of the workpiece changer; The rotating shaft and a guide rail are installed on the loading disc, the rotating shaft is connected with the rotator to provide the required power for micro abrasive particle spraying machining, the micro abrasive particle spraying system is connected with the guide rail of the loading disc, and the guide rail is distributed along the radius of the loading disc and is used for adjusting the machining radius to adapt to inner holes of workpieces of different sizes; The plasma generating system comprises a gas supply module, a radiation power supply module and a plasma excitation module, a plasma torch pipe of the plasma excitation module is arranged above the tool changer and is installed in cooperation with the left side of the tool changer; The micro abrasive particle spraying system comprises a abrasive particle supply module and a nozzle module, the abrasive particle supply module comprises an air compressor, an abrasive particle storage chamber and a pipe, the nozzle module comprises a nozzle body, a connecting cap and a nozzle, the left upper end of the abrasive particle storage chamber is connected with the air compressor, the right lower end of the abrasive particle storage chamber is connected with the nozzle module through the pipe, one end of the connecting cap of the nozzle module is matched with the nozzle body, the other end of the connecting cap is matched with the nozzle, the nozzle body is connected with the pipe, and the connecting cap is connected with the guide rail of the loading disc; The abrasive particle supply module further comprises a flow control valve, the flow control valve is arranged in the abrasive particle storage chamber; the abrasive particle supply module adopts flow limiting type feeding, in the process of micro abrasive particle spraying machining, the flow control valve is opened, and the micro abrasive particles can be accelerated to be sprayed out under the auxiliary action of high-speed airflow.

2. The plasma-assisted micro-abrasive blasting polishing machining apparatus according to claim 1, wherein A protective film is covered on the surface of the workpiece in the machining area, and the protective film protects the surface of the workpiece and prevents the surface of the workpiece from being oxidized by plasma and abraded by micro abrasive particles.

3. The apparatus according to claim 1, wherein the plasma auxiliary fine abrasive particle jet polishing machining apparatus is characterized by comprising: a plasma jet generator for generating a plasma jet; and a nozzle for jetting the plasma jet generated by the plasma jet generator toward the workpiece. The gas supplied by the gas supply module includes cooling gas, reaction gas and inert gas, the plasma excitation module includes a plasma torch pipe, an anti-resistance matcher, an induction coil and an electric spark generator, the gas supply tank of the gas supply module is connected with the cooling gas, the reaction gas and the inert gas through conduits respectively on the right side, wherein the inert gas and the reaction gas are mixed in the supply tank and then flow out from the internal pipe of the plasma torch pipe through the conduits, and the cooling gas flows out from the external pipe of the plasma torch pipe alone; the induction coil surrounds the bottom of the plasma torch pipe, the positive pole of the radio frequency power source of the radiation power module is connected to one end of the induction coil through the impedance matcher, the negative pole of the radio frequency power source and the other end of the induction coil are grounded, and the electric spark generator is located in the internal pipe of the plasma torch pipe.

4. The apparatus according to claim 1, wherein The nozzle of the nozzle module is a conical nozzle.

5. The apparatus according to claim 3, wherein the plasma jet is formed by a plasma torch. The cooling gas is helium or argon, the reaction gas is oxygen or water vapor, and the inert gas is helium or argon. The micro abrasive grains include one or at least two or more of a mixture of nanodiamond, boron carbide, silicon carbide, silicon nitride, silicon oxide, gallium oxide and aluminum oxide. The free radicals in the plasma have strong oxidizing properties and chemically react with atoms on the surface of the inner hole of the workpiece to form a denatured layer with low hardness.

6. A method as claimed in claim 1, wherein said plasma assisted micro-abrasive jet polishing machining apparatus is implemented. The method comprises the following steps: (1) fixing the connecting frame on the workpiece, ensuring that the center hole of the connecting frame is coaxial with the blind hole of the workpiece, and covering the surface of the workpiece in the machining area with a protective film; (2) starting the air suction pump to place the inner chamber of the connecting frame in a vacuum state, and then stopping the air suction pump; (3) controlling the tool converter to be adjusted to the plasma generation system; (4) starting the gas supply tank to allow the reaction gas and the inert gas to flow into the inner cavity of the plasma torch pipe, and the cooling gas to flow into the outer cavity of the plasma torch pipe; (5) starting the radio frequency power source and the electric spark generator, igniting and ionizing the inert gas through the electric spark igniter, flowing the high-frequency current generated by the radio frequency power source into the coil to generate a high-frequency induction magnetic field, and exciting the reaction gas to generate plasma; (6) controlling the tool converter to be adjusted to the micro abrasive grain spraying system; (7) adjusting the nozzle module so that the spraying point is aligned with the inner hole wall of the workpiece; (8) simultaneously starting the air compressor, the flow control valve and the rotation speed control tank, and performing circumferential shearing impact micro-removal on the denatured layer of the inner hole wall of the workpiece by the nozzle module; (9) stopping the flow control valve and starting the air suction pump, blowing the abrasive grains and chips in the inner hole of the workpiece into both sides of the inner chamber of the connecting frame, and then recycling them to the collection chamber through the air suction pump; (10) repeating the steps (2)-(9) for 2-3 times, and adjusting the repetition period of the above steps according to the actual workpiece machining process parameter index requirements; (11) turning off all switches and disassembling the connecting frame to complete the machining.

7. The method of claim 6, wherein, In the step (1), the protective film protects the surface of the workpiece to prevent the surface of the workpiece from being oxidized by the plasma and abraded by the micro abrasive grains.

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