Ceramic micropore laser ultrasonic combined machining method and system

Abstract

The invention provides a ceramic micropore laser ultrasonic combined machining method and system, and relates to the technical field of ceramic micropore machining. The ceramic micropore laser ultrasonic combined machining method comprises the following steps that a to-be-machined ceramic workpiece is pretreated; dividing a plurality of stacked reference layers on a to-be-processed area of the ceramic workpiece according to the depth of the to-be-processed micropore; and the reference layers on the ceramic workpiece are processed layer by layer in a laser processing and ultrasonic processing alternating mode until all the reference layers are processed, and the ceramic workpiece with the target micropores is obtained. Through mutual assistance of laser machining and ultrasonic machining, on one hand, the size of an area needing to be removed in ultrasonic machining can be reduced, tool abrasion is reduced, the service life of a tool is prolonged, the machining efficiency is improved, and the production cost is reduced; and on the other hand, a heat affected zone generated by laser machining can be removed, the machining quality of the micropores is guaranteed, and the high efficiency of laser machining and the high quality of ultrasonic machining are both considered.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of ceramic micropore processing, and in particular to a ceramic micropore laser-ultrasonic compound processing method and system. BACKGROUND

[0002] Ceramic materials represented by alumina, aluminum nitride and silicon nitride have unique advantages in mechanical, thermal and electrical properties, and are considered as the cornerstone materials of modern industry and technological progress. In the actual application process of ceramic materials, the ceramic blanks formed by dry pressing, cold isostatic pressing and high-temperature sintering need secondary finishing to realize specific functions. For example, there are more than 2000 large-depth-diameter-ratio micropores as gas flow channels on a certain semiconductor special ceramic electrostatic chuck / absorber. However, the ceramic material has the characteristics of high hardness, great brittleness, low toughness and weak impact resistance, which makes its processing challenging. The traditional processing method has the problems of serious tool wear, low material removal efficiency, limited processing quality and precision, etc. The processing of large-depth-diameter-ratio micropores of ceramic structural parts has become an important link to reduce production cost, expand application scenarios and realize market conversion.

[0003] With the rapid development of advanced laser technology, laser beams with narrow pulse width and small spot size are widely used in precision cutting and drilling due to their high energy density. Laser technology has obvious advantages in material processing removal, such as no limitation on the shape, size and processing environment of the processed object, high processing efficiency, no wear and no pollution, which is a green processing technology. However, due to the inherent characteristics of the laser beam and the corresponding material removal mechanism, the laser drilling faces the problems of poor indicators such as forming micropore taper, roundness and coaxiality. The random generation of residues such as slag particles in the processing process not only determines the quality of the hole wall / exit surface, but also seriously affects the feeding of the laser beam focus, which is a key factor related to whether the ceramic micropore is completely penetrated and the size of the corresponding exit diameter.

[0004] In order to avoid the problems existing in laser processing, at present, ultrasonic processing technology is mainly used to realize the large-depth-diameter-ratio micropore processing of semiconductor special ceramic electrostatic chuck / absorber. Specifically, the machine tool spindle is connected with the ultrasonic tool holder, and the ultrasonic auxiliary processing technology is used to realize high-quality drilling of high-hardness ceramic workpieces. Compared with traditional drilling, the ultrasonic processing technology propagates and transforms the ultrasonic vibration energy to the working area of the tool, forms impact on the cut material, reduces the cutting force and cutting heat without changing the material properties, timely separates and discharges the chips to reduce burrs, suppresses the subsurface damage to improve the surface quality. However, due to the large number of micropores to be processed and the large depth-diameter-ratio, slow cutting feeding will seriously limit the processing efficiency. SUMMARY

[0005] In view of this, the present invention proposes a laser-ultrasonic composite machining method and system for ceramic micropores. By using laser machining and ultrasonic machining to complement each other, on the one hand, it can reduce the volume of the area to be removed by ultrasonic machining, reduce tool wear, extend tool life, improve machining efficiency and reduce production costs; on the other hand, it can remove the heat-affected zone generated by laser machining, ensure the machining quality of micropores, and take into account both the high efficiency of laser machining and the high quality of ultrasonic machining.

[0006] The technical solution of this invention is implemented as follows: On one hand, the present invention provides a method for laser-ultrasonic composite processing of ceramic micropores, comprising the following steps: Pre-treatment of the ceramic workpiece to be processed; Based on the required depth of the micropores, several stacked reference layers are defined on the area to be processed of the ceramic workpiece. By alternating between laser processing and ultrasonic processing, the reference layer on the ceramic workpiece is processed layer by layer until all reference layers are processed, resulting in a ceramic workpiece with the target micropores. The alternation of laser processing and ultrasonic processing includes using a laser to remove material from a single reference layer to form a through hole, followed by using an ultrasonic tool to remove thermally damaged material and trim the pit walls.

[0007] Based on the above technical solutions, preferably, the pretreatment of the ceramic workpiece to be processed includes initial processing and surface treatment, wherein... The initial processing includes at least one of wire cutting, milling, and grinding, which is used to give the ceramic blank the shape and size of the ceramic workpiece to be processed; The surface treatment includes at least one of chemical mechanical polishing, plasma-assisted polishing, magnetorheological polishing and abrasive waterjet polishing, and the surface treatment is used to increase the surface finish of ceramic workpieces.

[0008] Based on the above technical solutions, preferably, the reference layer is provided with a heat-affected zone and a trimming zone, the heat-affected zone is a solid circle, and the trimming zone is located in a ring outside the heat-affected zone.

[0009] More preferably, the laser processing removes material from the heat-affected zone by laser according to preset laser parameters and laser posture trajectory, and forms waste to be processed in the trimming zone. The ultrasonic processing involves inserting an ultrasonic cutter into the heat-affected zone and removing the waste to be processed and some of the material attached to the micropore wall in the trimming zone by mechanical trimming according to preset ultrasonic parameters.

[0010] More preferably, the laser parameters are set to at least one of the following: laser wavelength 300nm-1100nm, pulse width 250 fs-20 ps, ​​output power 0.5 W-60 W, repetition frequency 1 kHz-1 MHz, defocus amount -20 µm-20 µm, and spot diameter 2 µm-12 µm.

[0011] More preferably, the ultrasonic parameters are set to at least one of the following: spindle speed of 5 krpm ~ 60 krpm, feed rate of 0.05 mm / min ~ 0.3 mm / min, ultrasonic amplitude of 10 µm ~ 25 µm, and frequency of 15 kHz ~ 40 kHz.

[0012] On the other hand, the present invention provides a ceramic micro-pore laser-ultrasonic composite processing system for realizing the above-mentioned ceramic micro-pore laser-ultrasonic composite processing method, including a laser processing device, an ultrasonic processing device and a processing platform. The processing platform is used to fix the pre-treated ceramic workpiece. The laser processing device and the ultrasonic processing device are both arranged above the processing platform and are used to perform laser processing and ultrasonic processing on the ceramic workpiece on the processing platform, respectively.

[0013] Based on the above technical solutions, preferably, the laser operation device includes a laser, a first rotating mirror, a second rotating mirror and a field lens. The laser operation device is provided with a laser optical path, which starts from the emitting end of the laser and passes through the first rotating mirror, the second rotating mirror and the field lens in sequence. The first rotating mirror and the second rotating mirror are used to change the laser pose trajectory of the laser beam.

[0014] Based on the above technical solutions, preferably, the ultrasonic working device includes a power amplifier, a spindle, an amplitude transformer, a transducer, and a drill bit. The power amplifier and the transducer are electrically connected, and the amplitude transformer, the transducer, and the drill bit are sequentially arranged on the spindle.

[0015] Based on the above technical solutions, preferably, the processing platform includes a carrier plate and a positioning base, the positioning base is disposed on the carrier plate, and the positioning base is used to fix the ceramic workpiece.

[0016] The ceramic micropore laser-ultrasonic composite processing method and system of the present invention have the following advantages over the prior art: (1) By combining laser processing and ultrasonic processing, on the one hand, the volume of the area to be removed by ultrasonic machining can be reduced, tool wear can be reduced and tool life can be extended, processing efficiency can be improved and production costs can be reduced; on the other hand, the heat-affected zone generated by laser processing can be removed, ensuring the processing quality of micro-holes, thus taking into account both the high efficiency of laser processing and the high quality of ultrasonic processing. (2) By layering the thickness of the area to be processed, and setting the preset parameters of laser processing and pose trajectory and the preset parameters of ultrasonic processing according to the layer thickness, the range of the heat-affected zone of laser processing and the influence of the inherent characteristics of the laser beam on the processing quality are effectively controlled. The heat-affected zone is removed by the ultrasonic impact effect of the tool. On the one hand, the laser softens the surrounding material while removing the material, which is conducive to ultrasonic mechanical trimming. On the other hand, the ultrasonic vibration tool intermittently impacts the hole wall, removing the heat-affected zone and removing the slag at the same time, thus realizing efficient and high-quality processing of ceramic micropores. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the steps of the ceramic micropore laser-ultrasonic composite processing method of the present invention; Figure 2 This is a schematic diagram of the reference layer division for the ceramic micropore laser-ultrasonic composite processing method of the present invention; Figure 3 This is a schematic diagram of the laser-ultrasonic composite machining method for ceramic micropores according to the present invention, which involves alternating laser and ultrasonic processing. Figure 4 This is a schematic diagram of the laser processing device of the ceramic micropore laser-ultrasonic composite processing system of the present invention; Figure 5 This is a schematic diagram of the ultrasonic operation device of the ceramic micropore laser-ultrasonic composite processing system of the present invention. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] Currently, laser processing and ultrasonic cutting are commonly used for micro-hole machining on ceramic workpieces. Laser processing generates heat, which creates a heat-affected zone around the micro-holes. Additionally, the uneven heat conduction caused by the flow and accumulation of molten slag during processing results in poor workpiece quality stability. Ultrasonic cutting, on the other hand, requires several hours of operation for multiple sets of micro-holes on a single ceramic workpiece, which is extremely time-consuming. This method combines laser and ultrasonic processing to overcome these shortcomings.

[0021] like Figures 1-3 As shown, the ceramic micropore laser-ultrasonic composite processing method of the present invention first divides the area to be processed into layers according to depth, and then uses ultrasonic laser to alternately process different layers to process the required micropores. The specific steps are as follows.

[0022] First, the material and parameters of the ceramic workpiece are selected. For ease of illustration, in this embodiment, alumina ceramic is selected for micropore processing. The micropore parameters are selected as follows: diameter 100 µm, hole depth 1 mm. It is made of alumina material and prepared by high-temperature sintering process. It has the characteristics of high purity, high hardness, and strong brittleness. The density is 3.7 g / cm3, the Vickers hardness is 13.7 GPa, the flexural strength is 350 MPa, the elastic modulus is 320 GPa, the Poisson's ratio is 0.23, and the micropore depth-to-diameter ratio is 10:1.

[0023] Pre-treatment of ceramic workpieces involves selecting suitable blanks and processing them to make them suitable for micro-hole machining operations.

[0024] The pretreatment of the ceramic workpiece to be processed includes initial processing and surface treatment. The initial processing includes at least one of wire cutting, milling, and grinding, which is used to give the ceramic blank the shape and size of the ceramic workpiece to be processed. The surface treatment includes at least one of chemical mechanical polishing, plasma-assisted polishing, magnetorheological polishing, and abrasive waterjet polishing, which is used to increase the surface finish of the ceramic workpiece.

[0025] Specifically, in some embodiments, the ceramic workpiece to be processed is pre-treated. The initial processing adopts wire cutting to make the ceramic blank into a cuboid shape with dimensions of 100 mm × 100 mm (length × width). The ceramic blank is ground with a grinding wheel to give it a preset thickness h = 1 mm. The surface treatment adopts chemical mechanical polishing to increase the surface smoothness of the initially processed ceramic workpiece. The laser adsorbent 9 is applied to enhance the absorption of laser light by the workpiece surface.

[0026] Based on the required micropore depth, several stacked reference layers are defined on the area to be processed of the ceramic workpiece. In some embodiments, such as... Figure 2 As shown, a non-uniform thickness method can be adopted. Based on the depth of the micro-hole to be processed, the material in the micro-hole is divided into layers from top to bottom: the first layer, the second layer, ..., the nth layer, and their depths are set as h1, h2, ..., hn, respectively. This makes the depth of each layer of the micro-hole decrease from top to bottom. In a specific embodiment, it is divided into five layers, and the thickness of each layer is set as h1=0.3 mm > h2=0.25 mm > h3=0.2 mm > h4=0.15 mm > h5=0.1 mm. This setting of thickness from large to small can maintain a high processing quality and consistency as much as possible under the influence of errors. In particular, it can accurately control the material removal depth and heat-affected zone range corresponding to laser processing, and realize the timely separation and discharge of slag and chips under ultrasonic vibration, ensuring the feed of the laser beam focus and the processing quality of ceramic micro-holes.

[0027] like Figure 3 As shown, when processing each reference layer, the reference layers on the ceramic workpiece are processed layer by layer by alternating between laser processing and ultrasonic processing until all reference layers are processed, resulting in a ceramic workpiece with the target micropores.

[0028] The alternation of laser processing and ultrasonic processing includes using a laser to remove material from a single reference layer to form a through hole, followed by using an ultrasonic tool to remove thermally damaged material and trim the pit walls.

[0029] In other words, when processing the reference layer, the stacked reference layers can be processed from top to bottom. When processing a certain reference layer, the material inside the micropore is first removed by laser processing, and then the inner wall of the hole and waste such as slag are removed by ultrasonic processing, and the inner wall of the hole is formed with high precision.

[0030] Specifically, a heat-affected zone and a trimming zone are provided on the reference layer. The heat-affected zone is a solid circle, and the trimming zone is a ring located outside the heat-affected zone. According to the set heat-affected zone, the material on the reference layer can be removed by laser along a spiral path. The diameter of the trimming zone must be consistent with the diameter of the hole. It should be noted that during the operation, the heat-affected zone formed by laser processing needs to be controlled within the trimming zone.

[0031] During the processing, the laser processing removes material from the heat-affected zone by laser according to preset laser parameters and laser posture trajectory, and forms waste to be processed in the trimming zone. The ultrasonic processing inserts an ultrasonic cutter into the heat-affected zone and removes the waste to be processed and some of the material attached to the micropore wall in the trimming zone by mechanical trimming according to preset ultrasonic parameters.

[0032] In some embodiments, the laser parameters are set to at least one of the following: laser wavelength 300nm-1100nm, pulse width 250 fs-20 ps, ​​output power 0.5 W-60 W, repetition frequency 1 kHz-1 MHz, defocus amount -20 µm-20 µm, and spot diameter 2 µm-12 µm.

[0033] In some embodiments, the ultrasonic parameters are set to at least one of the following: spindle speed of 5 krpm ~ 60 krpm, feed rate of 0.05 mm / min ~ 0.3 mm / min, ultrasonic amplitude of 10 µm ~ 25 µm, and frequency of 15 kHz ~ 40 kHz.

[0034] Since this embodiment uses reference layers of different thicknesses as examples for illustration, and the processing parameters for each layer are also set differently, a specific embodiment is given for ease of understanding.

[0035] The preset parameters for laser processing include: wavelength of 1030 nm, pulse width of 250 fs, output power of 59.8 / 45.0 / 25.3 / 20.6 / 10.2 W (first / second / third / fourth / fifth layers), repetition frequency of 700 / 600 / 360 / 250 / 100 kHz (first / second / third / fourth / fifth layers), defocusing amount of 0 mm, and spot diameter of 8.2 µm; the pose trajectory is as follows: Figure 4 As shown in d, the scanning speed is 80 / 100 / 120 / 250 / 300 mm / s (first layer / second layer / third layer / fourth layer / fifth layer), the jumping direction is from the inside to the outside, the scanning spacing is 3 µm, and the beam deflection angle is 3°.

[0036] It should be noted that the beam deflection angle is the angle between the center line of beam 7 and the center line of micro-aperture 8. The size is fixed, but the direction changes dynamically. The inherent characteristics of the laser beam are reduced to improve the processing quality by using deflection scanning.

[0037] The preset parameters for ultrasonic machining include: spindle speed of 5 / 12 / 28 / 45 / 60 krpm (first layer / second layer / third layer / fourth layer / fifth layer), feed rate of 0.2 / 0.18 / 0.12 / 0.08 / 0.05 mm / min (first layer / second layer / third layer / fourth layer / fifth layer), ultrasonic amplitude of 12 µm, vibration frequency of 20 kHz, and tool shape of double-edged with a drill tip angle of 118° and a diameter of 100 µm.

[0038] In this embodiment, the diameter of the laser-processed micro-hole is 90 µm, which is smaller than the preset micro-hole diameter d=100 µm. The corresponding heat-affected zone is less than 3 µm, which is limited to the area where the final material needs to be removed.

[0039] Correspondingly, the micro-hole diameter corresponding to the ultrasonic processing is 100 µm, which matches the final target hole diameter. That is, ultrasonic processing simultaneously realizes the initial processing of micro-hole enlargement and hole wall trimming, removing the heat-affected zone and irregular hole wall formed by laser initial processing.

[0040] To further facilitate understanding, another embodiment is provided in this example. In this other embodiment, aluminum nitride ceramic is microporously processed. The micropore parameters are set as follows: diameter 10 µm, pore depth 0.5 mm. It is made of aluminum nitride material and prepared by dry pressing process. It has the characteristics of high purity, high hardness, and high brittleness. The density is 3.3 g / cm3, the Vickers hardness is 10.4 GPa, the flexural strength is 310 MPa, the elastic modulus is 320 GPa, the Poisson's ratio is 0.23, the micropore depth-to-diameter ratio is 50:1, and the diameter d is 10 µm.

[0041] The preprocessing process is the same as in the previous embodiment, and will not be described again here.

[0042] In this embodiment, a non-uniform thickness method is used to divide the microholes to be processed into a first layer and a second layer from top to bottom, and their depths are set as h1 and h2 respectively, so that the depth of each layer of the microholes to be processed decreases from top to bottom, i.e., h1=0.3 mm>h2=0.2 mm. This allows for accurate control of the material removal depth and heat-affected zone range corresponding to laser processing, and also enables timely separation and discharge of slag and chips under ultrasonic vibration, ensuring the feed of the laser beam focus and the processing quality of the ceramic microholes.

[0043] Accordingly, the parameters for both laser processing and ultrasonic processing have been changed. The preset parameters for laser processing include: wavelength of 515 nm, pulse width of 10 ps, ​​output power of 50.2 / 34.6 W (first layer / second layer), repetition frequency of 0.8 / 1 MHz (first layer / second layer), defocus amount of 0 / 100 µm, and spot diameter of 3.2 µm. The pose trajectory includes: scanning speed of 0 mm / s, no jump direction, scanning interval of 0 µm, and beam deflection angle of 0°, meaning that there is no change in pose trajectory during laser processing.

[0044] The preset parameters for ultrasonic machining include: spindle speed of 30 / 45 krpm (first layer / second layer), feed rate of 0.15 / 0.05 mm / min (first layer / second layer), ultrasonic amplitude of 20 µm, vibration frequency of 40 kHz, and tool shape of double-edged with a drill tip angle of 135° and a diameter of 50 µm.

[0045] In this embodiment, the diameter of the laser-processed micro-hole is 3.2 µm, which is smaller than the preset micro-hole diameter d=10 µm. The corresponding heat-affected zone is less than 2.7 µm, which is limited to the area where the final material needs to be removed.

[0046] The ultrasonic processing corresponds to a micro-hole diameter of 10 µm, which matches the final target hole diameter. That is, ultrasonic processing simultaneously achieves micro-hole enlargement and hole wall trimming in the initial processing, removing the heat-affected zone and irregular hole wall formed by laser initial processing.

[0047] like Figures 4-5 As shown, the ceramic micropore laser-ultrasonic composite processing system of the present invention is used to realize the above-mentioned ceramic micropore laser-ultrasonic composite processing method. It includes a laser processing device, an ultrasonic processing device, and a processing platform. The processing platform is used to fix the pre-treated ceramic workpiece. The laser processing device and the ultrasonic processing device are both arranged above the processing platform and are used to perform laser processing and ultrasonic processing on the ceramic workpiece on the processing platform, respectively.

[0048] Specifically, such as Figure 4 As shown, the laser operation device includes a laser 1, a first rotating mirror 2, a second rotating mirror 3, and a field lens 4. The laser operation device is provided with a laser optical path. The laser optical path starts from the emitting end of the laser 1 and passes through the first rotating mirror 2, the second rotating mirror 3, and the field lens 4 in sequence. The first rotating mirror 2 and the second rotating mirror 3 are used to change the laser pose trajectory of the laser beam.

[0049] The laser beam generated by laser 1 is processed by beam expander 2 and aperture 3, and after its trajectory is adjusted by X-axis rotating mirror 4 and Y-axis rotating mirror 5, it enters field lens 6. After its position is adjusted, it is focused onto ceramic workpiece 10.

[0050] like Figure 5 As shown, the ultrasonic working device includes a power amplifier 13, a main shaft 14, an amplitude transformer 15, a transducer 16, and a drill bit 17. The power amplifier 13 and the transducer 16 are electrically connected, and the amplitude transformer 15, the transducer 16, and the drill bit 17 are sequentially arranged on the main shaft 14.

[0051] The spindle 14 is connected to the drill bit 17 via a tool holder. Through high-speed rotation and continuous feed, it contacts and impacts the workpiece 10. The power amplifier 13 drives the transducer 16 to generate an ultrasonic vibration signal. After the amplitude is amplified by the amplitude transformer 15, the drill bit 17 is controlled to vibrate at high frequency and low amplitude, achieving intermittent contact impact with the ceramic workpiece 10. The processing platform includes a carrier plate 12 and a positioning base 11. The positioning base 11 is disposed on the carrier plate 12 and is used to fix the ceramic workpiece.

[0052] In this embodiment, the carrier plate 12 has three orthogonal degrees of freedom: x, y, and z, with a positioning accuracy of 3 µm and a repeatability of 5 µm.

[0053] The entire processing procedure can be divided into steps S1-S7, as follows.

[0054] S1: Pre-treat the ceramic workpiece 10 and install and fix it on the carrier plate 12.

[0055] S2: Based on the thickness of the area to be processed in the ceramic workpiece 10, the depth h of the microhole 8 to be processed is divided into n layers, each of which is a reference layer.

[0056] S3: Based on the thickness of each layer of the micro-holes 8 to be processed set in S2, set the preset parameters and pose trajectory for laser processing; S4: By setting the preset parameters and pose trajectory of laser processing through S3, high-speed initial processing is performed on the micro-hole 8 reference layer set in S2. This reference layer is the uppermost reference layer for micro-processing. S5: Based on the thickness of each layer of the micro-hole 8 to be processed set in S2 and the preset parameters and pose trajectory of laser processing set in S3, set the preset parameters of ultrasonic processing; S6: Using the ultrasonic processing preset parameters set in S5, perform mechanical processing on a single reference layer of the micro-hole 8 initially processed by laser in S4; S7: Repeat steps S4 and S6 from top to bottom for the stacked reference layer, performing laser pre-processing and ultrasonic trimming in sequence until the micro-holes to be processed are completed.

[0057] This system combines the high efficiency of laser processing with the high quality of ultrasonic drilling. By using laser and ultrasonic processing in tandem, it can reduce the volume of the area to be removed by ultrasonic machining, reduce tool wear, extend tool life, improve processing efficiency, and reduce production costs. On the other hand, it can effectively solve the problems of poor taper, roundness, and coaxiality of laser-formed microholes, remove the heat-affected zone generated by laser processing, and ensure the processing quality of microholes.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for laser-ultrasonic composite processing of ceramic micropores, characterized in that, Includes the following steps: Pre-treatment of the ceramic workpiece to be processed; Based on the required depth of the micropores, several stacked reference layers are defined on the area to be processed of the ceramic workpiece. By alternating between laser processing and ultrasonic processing, the reference layer on the ceramic workpiece is processed layer by layer until all reference layers are processed, resulting in a ceramic workpiece with the target micropores. The alternation of laser processing and ultrasonic processing includes using a laser to remove material from a single reference layer to form a through hole, followed by using an ultrasonic tool to remove thermally damaged material and trim the pit walls.

2. The ceramic micropore laser-ultrasonic composite processing method as described in claim 1, characterized in that, The pretreatment of the ceramic workpiece to be processed includes initial processing and surface treatment, wherein... The initial processing includes at least one of wire cutting, milling, and grinding, which is used to give the ceramic blank the shape and size of the ceramic workpiece to be processed; The surface treatment includes at least one of chemical mechanical polishing, plasma-assisted polishing, magnetorheological polishing and abrasive waterjet polishing, and the surface treatment is used to increase the surface finish of ceramic workpieces.

3. The ceramic micropore laser-ultrasonic composite processing method as described in claim 1, characterized in that, The reference layer is provided with a heat-affected zone and a trimming zone. The heat-affected zone is a solid circle, and the trimming zone is a ring located outside the heat-affected zone.

4. The ceramic micropore laser-ultrasonic composite processing method as described in claim 3, characterized in that, The laser processing removes material from the heat-affected zone using a laser according to preset laser parameters and laser posture trajectory, forming waste material to be processed in the trimming zone. The ultrasonic processing inserts an ultrasonic cutter into the heat-affected zone and removes the waste material to be processed and some material attached to the micropore walls in the trimming zone by mechanical trimming according to preset ultrasonic parameters.

5. The ceramic micropore laser-ultrasonic composite processing method as described in claim 4, characterized in that, The laser parameters are set to at least one of the following: laser wavelength 300nm-1100nm, pulse width 250 fs ~ 20 ps, ​​output power 0.5 W ~ 60 W, repetition frequency 1 kHz ~ 1 MHz, defocus amount -20 µm ~ 20 µm, and spot diameter 2 µm ~ 12 µm.

6. The ceramic micropore laser-ultrasonic composite processing method as described in claim 4, characterized in that, The ultrasonic parameters are set to at least one of the following: spindle speed 5 krpm ~ 60 krpm, feed rate 0.05 mm / min ~ 0.3 mm / min, ultrasonic amplitude 10 µm ~ 25 µm, and frequency 15 kHz ~ 40 kHz.

7. A ceramic micropore laser-ultrasonic composite processing system, characterized in that, The method for laser-ultrasonic composite machining of ceramic micropores according to any one of claims 1-6 includes a laser working device, an ultrasonic working device, and a processing platform. The processing platform is used to fix the pre-treated ceramic workpiece. The laser working device and the ultrasonic working device are both disposed above the processing platform and are used to perform laser machining and ultrasonic machining on the ceramic workpiece on the processing platform, respectively.

8. The ceramic micropore laser-ultrasonic composite processing system as described in claim 7, characterized in that, The laser operation device includes a laser (1), a first rotating mirror (2), a second rotating mirror (3) and a field lens (4). The laser operation device is provided with a laser optical path. The laser optical path starts from the emitting end of the laser (1) and passes through the first rotating mirror (2), the second rotating mirror (3) and the field lens (4) in sequence. The first rotating mirror (2) and the second rotating mirror (3) are used to change the laser pose trajectory of the laser beam.

9. The ceramic micropore laser-ultrasonic composite processing system as described in claim 7, characterized in that, The ultrasonic working device includes a power amplifier (13), a spindle (14), an amplitude transformer (15), a transducer (16), and a drill bit (17). The power amplifier (13) and the transducer (16) are electrically connected. The amplitude transformer (15), the transducer (16), and the drill bit (17) are sequentially arranged on the spindle (14).

10. The ceramic micropore laser-ultrasonic composite processing system as described in claim 7, characterized in that, The processing platform includes a carrier plate (12) and a positioning base (11). The positioning base (11) is disposed on the carrier plate (12) and is used to fix the ceramic workpiece.

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