Partition adaptive laser waveform sealing groove inner surface microstructure processing method and device

Abstract

This invention proposes a method and apparatus for processing microstructures on the inner surface of sealing grooves using zoned laser waveform adaptation, belonging to the field of aero-engine sealing technology. The processing method determines the boundary position of the inner surface of the sealing groove based on its inner surface parameters, and divides the inner surface of the sealing groove into a central bottom region and a corner region based on this boundary position. Different lasers are used for the central bottom region and the corner region (a square laser beam is used for the central bottom region, and a Gaussian laser beam is used for the corner region), thus adapting different laser waveforms to each zone. When processing sealing grooves (smaller structures), this reduces the heat-affected zone of the laser, solves the technical problem of product defects such as heat-induced microcracks, steps, or scratches easily occurring at corners, and improves the processing quality of the sealing groove.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine sealing technology and relates to the technical improvement of sealing grooves on aero-engines. Specifically, it is a method and device for processing microstructures on the inner surface of sealing grooves with zoned adaptation to laser waveforms. Background Technology

[0002] In aero-engines, the control of leakage of the medium (gas or liquid) directly determines the efficiency and reliability of the equipment. As the core sealing structure carrier, the quality of the sealing groove has become one of the key factors restricting the improvement of the sealing performance of aero-engines.

[0003] Traditional sealing grooves are equipped with sealing rings. During operation, the sealing groove relies on the elastic deformation of the sealing ring and the pressure of the medium to achieve a contact seal and block medium leakage. Therefore, this traditional sealing groove is suitable for aero engines with low speed and low heat generation. However, with the continuous development of aero engine technology, it is moving towards high temperature, high pressure, and high speed. When the aero engine speed is too high and the heat generation is high, it forms a high-temperature operating state. Under high temperature, the sealing ring will soften and relax under stress, lose its elasticity, and thus fail to effectively block the leakage channel, leading to seal failure.

[0004] To address the issue of sealing failure when traditional sealing grooves and sealing rings fail under high engine speeds and heat generation, some existing technologies have proposed incorporating microstructures on the inner surface of the sealing groove. These microstructures include micro-protrusions or micro-grooves, such as herringbone or V-shaped grooves. During high-speed operation of the aero-engine, these micro-protrusions or micro-grooves act like micro-oil pumps, pumping the leaking medium (gas or liquid) into the sealing gap (primarily through asymmetrical microstructure design guiding the leaking medium towards the high-pressure side or oil collection tank), forming a high-pressure gas or liquid film, thus achieving a non-contact seal.

[0005] However, since sealing grooves are made of superhard materials or composite materials, which have extremely high hardness, wear resistance and excellent high-temperature mechanical properties, existing technologies mostly use laser etching for superhard materials or composite materials. However, the size of sealing grooves is small, while the heat-affected zone of lasers is large. On the inner surface of sealing grooves, especially at corners, product defects such as thermally induced microcracks, steps or scratches are prone to appear, affecting the processing quality of sealing grooves. Summary of the Invention

[0006] In view of the technical problem described in the background art above, when using lasers to process microstructures on the inner surface of sealing grooves, product defects such as microcracks, steps or scratches are easily generated at the corners, which affects the processing quality of the sealing grooves. In order to address this technical problem, the present invention proposes a method and apparatus for processing microstructures on the inner surface of sealing grooves with zone-adaptive laser waveforms.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A method for fabricating microstructures on the inner surface of a sealing groove with partitioned laser waveform adaptation includes the following steps: S1: Obtain the inner surface parameters of the sealing groove; S2: Determine the boundary position of the inner surface of the sealing groove according to the inner surface parameters, and divide the inner surface of the sealing groove into the middle area of ​​the bottom of the groove and the corner area according to the boundary position; S3: Set the processing path; S4: Simultaneously start the laser modification device and the ultrasonic grinding device. According to the set processing path, use the laser modification device to generate a square laser beam to perform laser modification on the middle area of ​​the bottom of the tank. At the same time, use the ultrasonic grinding device to perform ultrasonic grinding to process microstructures in the middle area of ​​the bottom of the tank. The relationship between the depth of laser modification h1 and the depth of ultrasonic grinding h2 is: (h1-10)μm≤h2≤(h1-5)μm. When the boundary position is reached, the laser modification device switches to a Gaussian laser beam to perform laser modification on the corner area, and at the same time, an ultrasonic grinding device is used to perform ultrasonic grinding to process microstructures in the corner area; wherein, the relationship between the laser modification depth h1 and the ultrasonic grinding depth h2 is: (h1-10)μm≤h2≤(h1-5)μm; Once the corner area is processed, the microstructure of the inner surface of the sealing groove is complete.

[0008] Further specifying, S4 specifically refers to: S4.1: Simultaneously start the laser modification device and the ultrasonic grinding device. According to the set processing path, use the laser modification device to generate a square laser beam to perform laser modification on the middle area of ​​the bottom of the tank. At the same time, use the ultrasonic grinding device to perform ultrasonic grinding. The depth of laser modification is at least 5 μm greater than the depth of ultrasonic grinding in order to process microstructures in the middle area of ​​the bottom of the tank. The parameters of the square laser beam are: spot diameter 50 μm ~ 100 μm, vertical incidence, energy flux Φ = 2.0 J / cm² ~ 3.8 J / cm², and scanning speed 3 mm / s ~ 10 mm / s. S4.2: During the modification process in the middle area of ​​the tank bottom, the position parameters of the laser modification device are collected in real time. When it is determined that the laser modification device has reached the boundary position based on the position parameters of the laser modification device, the laser modification device is controlled to switch the square laser beam to a Gaussian laser beam and S4.3 is executed; otherwise, S4.1 is executed. S4.3: Laser modification of the corner area is performed using a Gaussian laser beam, while ultrasonic grinding is performed simultaneously in the corner area using an ultrasonic grinding device. The depth of laser modification is at least 5 μm greater than the depth of ultrasonic grinding, in order to process microstructures in the corner area. The parameters of the Gaussian laser beam are: spot diameter 30 μm~60 μm, energy flux Φ = 1.5 J / cm²~2.5 J / cm², and scanning speed 2 mm / s~8 mm / s. S4.4: During the corner area modification process, the position parameters of the laser modification device are collected in real time. When the corner area processing is completed based on the position parameters of the laser modification device, the laser modification device and the ultrasonic grinding device are stopped to complete the processing of the microstructure on the inner surface of the sealing groove; otherwise, S4.3 is executed.

[0009] Further specifying the synchronization time difference between the laser modification device and the ultrasonic grinding device Second.

[0010] Further specifying, the parameters of the ultrasonic grinding device are: ultrasonic frequency 15 kHz - 40 kHz, ultrasonic amplitude 2 μm - 10 μm.

[0011] Further defining the boundary, a cross-section is drawn along the depth direction of the sealing groove. Using this cross-section as a reference, the midpoint of the bottom of the sealing groove is taken as the origin, and the width direction of the groove bottom is taken as the X direction. The boundary position is then determined according to the following formula: In the formula, X is the dividing position, in mm; W is the width of the groove bottom, in mm; The distance between the dividing point and the bottom edge of the trench, in mm.

[0012] Further specifying, the coverage length of the corner area is determined according to the following formula: In the formula, R is the distance between the dividing point and the bottom edge of the tank, in mm; R is the radius of curvature of the corner, in mm. The laser compensation length is 0.01 mm to 0.05 mm.

[0013] Further specifying, when modifying the corner region, the incident angle of the Gaussian laser beam... The relationship with the microstructure morphology of the inner surface of the sealing groove is as follows: In the formula, The angle of inclination of the inner wall of the sealing groove, in degrees; This is a correction factor, with a value range of 350° / mm to 500° / mm; Radius of curvature of the corner, unit: mm.

[0014] Furthermore, the relationship between the radius of curvature R of the turning angle and the width W of the groove bottom is: R≤W / 4.

[0015] A microstructure processing device for the inner surface of a sealing groove with zone-adaptive laser waveform, used to realize the above-mentioned microstructure processing method for the inner surface of a sealing groove with zone-adaptive laser waveform, includes a laser modification device, an angle sensor, an ultrasonic grinding device, a control system, and a positioning workpiece and a position sensor. The positioning workpiece is used to fix and install the sealing groove during processing; The position sensor is installed on the positioning workpiece and connected to the control system signal. It is used to collect the position parameters of the laser modification device in real time during processing and send the position parameters to the control system. The angle sensor is installed on the laser modification device and connected to the control system signal. It is used to collect the angle parameters of the laser modification device in real time and send the angle parameters to the control system. The control system is electrically connected to the position sensor, angle sensor, ultrasonic grinding device, and laser modification device. The control system is used to receive position parameters and angle parameters, determine the processing position of the laser modification device based on the position parameters, and feed back the processing position to the ultrasonic grinding device and the laser modification device. The control system also adjusts the incident angle of the square laser beam or Gaussian laser beam based on the angle parameters. The laser modification device is used to perform laser modification on the middle area or corner area of ​​the bottom of the tank; The ultrasonic grinding device is used to simultaneously perform ultrasonic grinding on the laser-modified area after the laser modification device has completed laser modification of the middle area or corner area of ​​the bottom of the groove. Specifically, the depth of laser modification is at least 5 μm greater than the depth of ultrasonic grinding to process microstructures in the middle or corner areas of the groove bottom; the synchronization time difference between the laser modification device and the ultrasonic grinding device... Second.

[0016] Further specifying, the laser modification device includes a picosecond laser generator and a DMD digital micromirror and an optical imaging system arranged sequentially along the laser emission direction. The DMD digital micromirror is used to shape the laser generated by the picosecond laser generator into a square laser beam or a Gaussian laser beam. The square laser beam is projected onto the middle area of ​​the bottom of the sealing groove after passing through the optical imaging system, and the middle area of ​​the bottom of the groove is laser modified. The Gaussian laser beam is projected onto the corner area of ​​the sealing groove after passing through the optical imaging system, and the corner area is laser modified.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The microstructure processing method for the inner surface of a sealing groove with zoned adaptation laser waveform of the present invention determines the boundary position of the inner surface of the sealing groove according to the inner surface parameters of the sealing groove, and divides the inner surface of the sealing groove into a middle area of ​​the groove bottom and a corner area according to the boundary position. Different lasers are used for the middle area of ​​the groove bottom and the corner area respectively (a square laser beam is used for the middle area of ​​the groove bottom and a Gaussian laser beam is used for the corner area), realizing zoned adaptation of lasers with different waveforms. In this way, when processing sealing grooves (small-sized structures), the heat-affected zone of the laser is reduced, solving the technical problem that product defects such as thermally induced microcracks, steps or scratches are prone to occur at the corners, and improving the processing quality of the sealing groove. In addition, this application controls the depth of laser modification and the depth of ultrasonic grinding so that the depth of laser modification is at least 5μm greater than the depth of ultrasonic grinding, thereby forming microstructures in the middle area of ​​the groove bottom and the corner area.

[0018] (2) The microstructure processing method of the inner surface of the sealing groove with zone-adaptive laser waveform of the present invention utilizes laser modification device and ultrasonic grinding device for synchronous processing, realizing the deep coupling of laser modification process and ultrasonic grinding process in time domain and space (same time and same trajectory). Ultrasonic grinding is performed during the window period after laser modification to remove material, maximize the utilization efficiency of softening effect, significantly reduce grinding force, suppress the generation of defects such as reinforcing phase pull-out, matrix tearing, and subsurface microcracks, and realize efficient and low-damage precision processing of sealing groove structure.

[0019] (3) When modifying the corner region, the present invention utilizes the incident angle of the Gaussian laser beam. The relationship between the microstructure morphology of the inner surface of the sealing groove and the modification of the corner region solves the problem of laser obstruction in the deep cavity structure. At the same time, by utilizing the elliptical spot projection characteristics of the Gaussian laser beam, a continuous and smooth transition of the modified layer at the corner is achieved.

[0020] (4) In the process of simultaneous processing of laser-modified devices and ultrasonic grinding devices, the present invention controls the synchronization time difference between the two. The precision of the machining trajectory for the sealing groove (narrow and deep groove) ensures accuracy and avoids groove width deviation.

[0021] (5) The present invention uses a square laser beam in the middle area of ​​the bottom of the tank and a Gaussian laser beam in the corner area. The square laser beam has a uniform energy distribution and a steep edge transition. With a high effective energy flux, it can achieve efficient large-area modification of the middle area of ​​the bottom of the tank. The Gaussian laser beam has a concentrated energy spot. With a lower effective energy flux, it can achieve fine modification of the narrow corner space, avoiding excessive ablation and damage to the corner area due to excessive energy. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the microstructure processing method for the inner surface of the sealing groove with partitioned adaptive laser waveform according to the present invention; Figure 2 This is a schematic diagram of the microstructure processing device for the inner surface of the sealing groove that adapts to the laser waveform in the partitioning method according to the present invention; Figure 3 This is a schematic diagram of an optical imaging system; Figure 4 The diagram shows a ring-shaped Gaussian laser beam and a square laser beam, where a is a ring-shaped Gaussian beam and b is a flat-top beam. Figure 5 This is a schematic diagram showing the relationship between the laser incident angle and the corner morphology. Figure 6 This is a schematic diagram of the processing path; Explanation of reference numerals in the attached figures: 1- Picosecond laser generator, 2- DMD digital micromirror, 3- Optical imaging system, 31- Lens, 32- Charge-coupled device, 4- Angle sensor, 5- Ultrasonic grinding device, 6- Control system, 7- Positioning workpiece, 8- Sealing groove. Detailed Implementation

[0023] The technical solution of the present invention will be further explained and described below with reference to the accompanying drawings and specific embodiments, but the present invention is not limited to the embodiments described below.

[0024] See Figure 1 This invention proposes a method for fabricating microstructures on the inner surface of a sealing groove with partitioned adaptive laser waveforms, comprising the following steps: S1: Obtain the inner surface parameters of the sealing groove 8; specifically, the sealing groove 8 itself is an existing conventional structure, and its inner surface parameters are specifically determined by the structural dimensions of the sealing groove 8. As a preferred embodiment of the present invention, the groove width W of the sealing groove 8 is ≤0.5mm, and the depth-to-width ratio H / W is ≥6:1.

[0025] S2: Determine the boundary position of the inner surface of the sealing groove based on the inner surface parameters, and divide the inner surface of the sealing groove 8 into the middle area of ​​the groove bottom and the corner area based on the boundary position; The method for determining the boundary position is as follows: A cross-section is drawn along the depth direction of the sealing groove 8. Using this cross-section as a reference, the midpoint of the bottom of the sealing groove 8 is taken as the origin, the width direction of the groove bottom is taken as the X direction, and the depth direction is taken as the Y direction. The boundary position is then determined according to the following formula: In the formula, X is the dividing position, in mm; W is the width of the groove bottom, in mm; The distance between the dividing point and the edge of the tank bottom, in mm. It is set by the operator according to the requirements.

[0026] Therefore, the dividing position is a straight line extending along the length of the groove bottom in the X direction, which is the same as the direction of laser scanning.

[0027] S3: Set the processing path; the processing path is set by the operator. For details, see [link to documentation]. Figure 6 In a preferred embodiment of the present invention, the processing path is a zigzag path formed by reciprocating scanning.

[0028] S4: Simultaneously start the laser modification device and the ultrasonic grinding device 5. According to the set processing path, use the laser modification device to generate a square laser beam to perform laser modification on the middle area of ​​the bottom of the tank. At the same time, use the ultrasonic grinding device 5 to perform ultrasonic grinding to process microstructures in the middle area of ​​the bottom of the tank. The relationship between the depth of laser modification h1 and the depth of ultrasonic grinding h2 is: (h1-10)μm≤h2≤(h1-5)μm. When the boundary position is reached, the laser modification device switches to a Gaussian laser beam to perform laser modification on the corner area, and simultaneously uses ultrasonic grinding device 5 to perform ultrasonic grinding to process microstructures in the corner area; wherein, the relationship between the laser modification depth h1 and the ultrasonic grinding depth h2 is: (h1-10)μm≤h2≤(h1-5)μm; Once the corner area is processed, the microstructure of the inner surface of the sealing groove is complete.

[0029] In this invention, S4 specifically refers to: S4.1: Simultaneously activate the laser modification device and ultrasonic grinding device 5. Following the set processing path, use the laser modification device to generate a square laser beam to perform laser modification on the central area of ​​the tank bottom. Simultaneously, use the ultrasonic grinding device 5 to perform ultrasonic grinding to process microstructures in the central area of ​​the tank bottom. The relationship between the laser modification depth h1 and the ultrasonic grinding depth h2 is: (h1-10)μm≤h2≤(h1-5)μm. The parameters of the square laser beam are: spot diameter 50μm~100μm, perpendicular incidence, energy flux Φ=2.0 J / cm²~3.8 J / cm², and scanning speed 3 mm / s~10 mm / s. Specifically, the spot diameter of the square laser beam can be 50μm, 60μm, 70μm, 80μm, 90μm, or 100μm. The square laser beam is incident perpendicular to the tank bottom to the central area for laser modification. The energy flux of the square laser beam can be 2.0 J / cm²~3.8 J / cm². J / cm², 2.3 J / cm², 2.5 J / cm², 2.8 J / cm², 3.0 J / cm², 3.3 J / cm², 3.5 J / cm² or 3.8 J / cm²; scanning speed can be 3 mm / s, 5 mm / s, 8 mm / s or 10 mm / s.

[0030] S4.2: During the modification process in the middle area of ​​the tank bottom, the position parameters of the laser modification device are collected in real time. When it is determined that the laser modification device has reached the boundary position based on the position parameters of the laser modification device, the laser modification device is controlled to switch the square laser beam to a Gaussian laser beam and S4.3 is executed; otherwise, S4.1 is executed. S4.3: Laser modification of the corner area is performed using a Gaussian laser beam, while ultrasonic grinding device 5 is simultaneously used to perform ultrasonic grinding in the corner area. See [link to documentation]. Figure 4 This diagram illustrates the Gaussian and square laser beams generated by a laser-modified device for processing microstructures in corner regions. The relationship between the laser modification depth h1 and the ultrasonic grinding depth h2 is: (h1-10) μm ≤ h2 ≤ (h1-5) μm. The parameters of the Gaussian laser beam are: spot diameter 30 μm~60 μm, energy flux Φ = 1.5 J / cm²~2.5 J / cm², and scanning speed 2 mm / s~8 mm / s. Specifically, the spot diameter of the Gaussian laser beam is 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, or 60 μm; the energy flux is 1.5 J / cm², 1.8 J / cm², 2.0 J / cm², 1.3 J / cm², or 2.5 J / cm²; and the scanning speed is 2 mm / s, 5 mm / s, or 8 mm / s. (See also...) Figure 5 The incident angle of a Gaussian laser beam is determined as follows: [The text abruptly ends here, so the translation stops.] The relationship with the microstructure morphology of the inner surface of the sealing groove is as follows: In the formula, The angle of inclination of the inner wall of the sealing groove, in degrees; This is a correction factor, which is set by the operator according to the requirements. The value ranges from 350° / mm to 500° / mm, specifically 350° / mm, 400° / mm, 450° / mm or 500° / mm. The radius of curvature of the corner is expressed in mm. The radius of curvature of the corner is a structural parameter of the sealing groove 8. As the radius of curvature of the corner R increases, the correction coefficient K tends to decrease. Specifically, when R = 0.12 mm, k = 350° / mm; when R = 0.1 mm, k = 400° / mm; when R = 0.09 mm, k = 450° / mm; and when R = 0.08 mm, k = 500° / mm.

[0031] S4.4: During the corner area modification process, the position parameters of the laser modification device are collected in real time. When the corner area processing is completed based on the position parameters of the laser modification device, the operation of the laser modification device and the ultrasonic grinding device 5 is stopped, and the processing of the microstructure on the inner surface of the sealing groove is completed; otherwise, S4.3 is continued.

[0032] In this invention, when processing microstructures in the middle and corner areas of the groove bottom, the depth of laser modification and the depth of ultrasonic grinding are controlled by the control system 6. In a preferred embodiment of this invention, the depth of laser modification is 150 μm, which is at least 5 μm greater than the depth of ultrasonic grinding. Preferably, the depth of laser modification is 5 μm-10 μm greater than the depth of ultrasonic grinding, i.e., the depth of ultrasonic grinding is 140 μm-145 μm.

[0033] In a preferred embodiment of the present invention, the synchronization time difference between the laser modification device and the ultrasonic grinding device 5 is... Second.

[0034] In a preferred embodiment of the present invention, the parameters of the ultrasonic grinding device 5 are: ultrasonic frequency 15 kHz - 40 kHz, ultrasonic amplitude 2 μm - 10 μm; specifically, the ultrasonic frequency can be 15 kHz, 20 kHz, 25 kHz, 30 kHz, 35 kHz or 40 kHz; the ultrasonic amplitude is 2 μm, 3 μm, 5 μm, 8 μm or 10 μm.

[0035] In this invention, the coverage length of the corner area is determined according to the following formula: In the formula, R is the distance between the dividing point and the bottom edge of the tank, in mm; R is the radius of curvature of the corner, in mm. The coverage length of the corner area is set by the operator according to the requirements of the laser compensation length, and the value is 0.01 mm to 0.05 mm. The specific value can be 0.01 mm, 0.02 mm, 0.03 mm, 0.04 mm or 0.05 mm.

[0036] The completion of processing in the aforementioned corner area refers to the coverage length of the corner area reached by the processing position.

[0037] In a preferred embodiment of the present invention, the relationship between the radius of curvature R of the turning angle and the width W of the groove bottom is: R≤W / 4.

[0038] The following describes the microstructure processing method for the inner surface of a sealing groove according to the present invention, using the processing of a sealing groove 8 with dimensions of groove width W=0.45 mm, groove depth 3.0 mm, depth-to-width ratio 7:1, corner curvature radius R=0.1 mm, right-angle corner, wall inclination angle θ=90°, and tolerance ≤±0.1 mm as an example: Select a silicon carbide superhard material workpiece, use anhydrous ethanol to perform ultrasonic cleaning and deburring on the workpiece surface to remove surface oil and impurities, and cut out a sealing groove 8.

[0039] Picosecond laser generator 1 was selected with a wavelength of 532 nm, a pulse width of 30 ps, ​​a pulse repetition frequency of 150 kHz, and a laser power of P=24 W. The DMD digital micromirror 2 was adjusted to square laser mode to ensure smooth switching of the square laser beam and that the beam focusing accuracy met the standard. The rotatable laser emitter head was adjusted and the angle sensor was calibrated to ensure that the incident angle adjustment range was 0°~10° and the angle accuracy was ±0.1°. The three-dimensional moving platform (the device on which the picosecond laser generator 1 is installed) was calibrated to ensure a positioning accuracy of ±0.001 mm, which ensures that the slot width tolerance is ≤±0.1 mm. The ultrasonic grinding device 5 was adjusted to an ultrasonic frequency of 25 kHz and an amplitude of 5 μm (bottom of the groove) and 3 μm (corner machining), which is lower than the conventional parameters to avoid interference between the grinding head and the groove wall. The diamond grinding head was selected with a fine grit (1200 mesh) and a diameter of 0.2 mm, which is suitable for a groove width of W=0.4 mm. The grinding head speed was adjusted to 8000 r / min and the feed rate f=100 mm / min. The sealing groove 8 was installed on the positioning workpiece 8, and the control system 6 was adjusted. The time synchronization error between laser and ultrasonic grinding was ≤0.1 s and the position deviation was ≤0.001 mm.

[0040] Determine the boundary location, based on and Substituting W=0.45 mm and R=0.1 mm, the calculation yields... =0.15 mm, =-0.1 mm; thus, the middle area of ​​the trench bottom can be obtained as The region between -0.1 mm and x = 0.1 mm, including the corner region. <-0.1 mm and >0.1 mm, including corner arcs and extended areas; the angle of incidence in the corner area is calculated based on... Substituting θ=90°, k=400° / mm, and R=0.1 mm, we calculate α=5°. We take α=5° as the incident angle for corner processing to ensure full laser irradiation coverage in the corner area of ​​the narrow deep groove.

[0041] Synchronous processing operation: Processing of the middle area of ​​the tank bottom: Activate the synchronous control module, switch the laser to a square laser beam, with the laser incident perpendicularly (0°), a spot size of 100 μm (adapted to a 0.45 mm tank width), and a scanning speed v = 5 mm / s; the laser synchronously modifies the middle area of ​​the tank bottom, forming a 150 μm thick modified layer; simultaneously, the ultrasonic grinding head grinds synchronously at an ultrasonic frequency of 25 kHz, an amplitude of 5 μm, a grinding head speed of 8000 r / min, and a feed rate of 100 mm / min, achieving rapid and low-damage removal of the modified layer while strictly controlling the tank width. Corner area processing: When processing reaches the dividing position... =-0.1 mm and When the laser diameter is 0.1 mm, the synchronous control module controls the laser modification device to automatically switch the laser to a Gaussian laser beam, while adjusting the incident angle to 5°. The energy flux of the Gaussian laser beam is 1.5 J / cm², and the processing speed is reduced to 4 mm / s. The ultrasonic grinding head adjusts its amplitude to 3 μm, keeps the rotation speed and feed speed constant, and grinds synchronously to avoid interference between the grinding head and the groove wall. The angle sensor monitors the incident angle in real time. If a deviation occurs (Δα>0.5°), the control system automatically corrects it to ensure angle stability.

[0042] Inspection and correction: After processing, a three-dimensional confocal microscope is used to inspect the flatness of the groove bottom, the groove width and the depth-to-width ratio, a roughness tester is used to inspect the surface roughness, and calipers are used to inspect the corner radius and dimensional accuracy.

[0043] See Figure 2 The present invention also proposes a microstructure processing device for the inner surface of a sealing groove with partitioned adaptation laser waveform, which is used to realize the above-mentioned microstructure processing method for the inner surface of a sealing groove with partitioned adaptation laser waveform. The device is characterized by including a laser modification device, an angle sensor 4, an ultrasonic grinding device 5, a control system 6, a positioning workpiece 7, and a position sensor. The positioning workpiece 7 is used to fix the sealing groove 8 during processing; A position sensor is installed on the positioning workpiece 7 and connected to the control system signal. It is used to collect the position parameters of the laser modification device in real time during processing and send the position parameters to the control system 6. Angle sensor 4 is installed on the laser modification device and connected to the control system signal to collect the angle parameters of the laser modification device in real time and send the angle parameters to the control system 6. The control system 6 is electrically connected to the position sensor, angle sensor 4, ultrasonic grinding device 5, and laser modification device. The control system 6 receives position and angle parameters, determines the processing position of the laser modification device based on the position parameters, and feeds back the processing position to the ultrasonic grinding device 5 and the laser modification device. The control system 6 also adjusts the incident angle of the square laser beam or Gaussian laser beam based on the angle parameters. Furthermore, the control system 6 controls the depth of laser modification and the depth of ultrasonic grinding. Specifically, the depth of laser modification and the depth of ultrasonic grinding are set before processing. The control system controls the laser modification device to perform laser modification based on the set laser modification depth, and controls the ultrasonic grinding device 5 to perform ultrasonic grinding based on the set ultrasonic grinding depth. The control system 6 also controls the ultrasonic grinding device 5 to synchronously perform ultrasonic grinding and laser modification with the laser modification device. Laser modification devices are used to perform laser modification on the middle or corner areas of the bottom of a tank. The ultrasonic grinding device 5 is used to simultaneously perform ultrasonic grinding on the laser-modified area after the laser modification device has completed the laser modification of the middle area or corner area of ​​the bottom of the tank. In a preferred embodiment of the present invention, the control system 6 includes a servo control module, a synchronization control module, and a positioning control module. The servo control module is connected to both an angle sensor and a laser incident angle adjustment module. The angle data detected by the angle sensor is sent to the servo control module in real time. The servo control module determines whether the laser incident angle is appropriate based on the angle data, thereby controlling the laser incident angle. The synchronization control module is connected to the laser modification device and the ultrasonic grinding device 5, and is used to control the laser modification depth of the laser modification device and the ultrasonic grinding depth of the ultrasonic grinding device 5 according to the set laser modification depth and ultrasonic grinding depth. The positioning control module is connected to a position sensor. The position sensor sends the real-time detected position data to the positioning control module. The positioning control module determines whether the installation position of the sealing groove 8 is appropriate based on the position data, and then provides feedback to the operator. The operator adjusts the position of the sealing groove 8 according to the feedback from the positioning control module.

[0044] The laser modification depth is at least 5 μm greater than the ultrasonic grinding depth to process microstructures in the middle or corner areas of the groove bottom. Preferably, the laser modification depth is 5 μm-10 μm greater than the ultrasonic grinding depth, i.e., the ultrasonic grinding depth is 140 μm-145 μm. The synchronization time difference between the laser modification device and the ultrasonic grinding device 5... Second.

[0045] In this invention, the laser modification device includes a picosecond laser generator 1, a DMD digital micromirror 2, and an optical imaging system 3 arranged sequentially along the laser emission direction. The DMD digital micromirror 2 is used to shape the laser generated by the picosecond laser generator 1 into a square laser beam or a Gaussian laser beam. The square laser beam is projected onto the middle region of the bottom of the sealing groove 8 after passing through the optical imaging system 3, thereby performing laser modification on the middle region of the bottom of the groove. The Gaussian laser beam is projected onto the corner region of the sealing groove 8 after passing through the optical imaging system 3, thereby performing laser modification on the corner region. The optical imaging system 3 is a 4f optical system. See [link to relevant documentation]. Figure 3 The optical imaging system 3 consists of two lenses 31 and a charge-coupled device 32. The parameters of the laser generated by the picosecond laser generator 1 are: wavelength 532 nm, pulse width 30 ps, ​​and pulse repetition frequency 200 kHz; see [link to relevant documentation]. Figure 4 The DMD digital micromirror 2 adjusts the laser generated by the picosecond laser generator 1 into a ring or square light field in real time, that is, a square laser beam or a Gaussian laser beam.

[0046] In a preferred embodiment of the present invention, the laser modification device further includes a laser incident angle adjustment module, which includes a rotatable laser emitter. Specifically, the rotatable laser emitter is electrically connected to a servo control module, which controls the emission angle of the rotatable laser emitter to precisely adjust the incident angle of the Gaussian laser beam at the corner region.

[0047] In a preferred embodiment of the present invention, the ultrasonic grinding device 5 includes an ultrasonic generator, an ultrasonic grinding spindle, and a diamond grinding head. The ultrasonic frequency is 20 kHz to 40 kHz, and the amplitude is adjustable from 5 μm to 15 μm. The diamond grinding head uses fine-grained abrasive to reduce processing damage. The grinding head speed can be adjusted as needed, taking into account both grinding efficiency and surface quality.

[0048] The above description is only used to illustrate the technical solutions of the present invention, and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing, those skilled in the art should understand that modifications can still be made to the technical solutions described above, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A method for processing the inner surface microstructure of a seal groove of a partition-adapted laser waveform, characterized by, Includes the following steps: S1: Obtain the inner surface parameters of the sealing groove (8); S2: Determine the boundary position of the inner surface of the sealing groove according to the inner surface parameters, and divide the inner surface of the sealing groove (8) into the middle area of ​​the bottom of the groove and the corner area according to the boundary position; S3: Set the processing path; S4: Simultaneously start the laser modification device and the ultrasonic grinding device (5). According to the set processing path, use the laser modification device to generate a square laser beam to perform laser modification on the middle area of ​​the bottom of the tank. At the same time, use the ultrasonic grinding device (5) to perform ultrasonic grinding to process microstructures in the middle area of ​​the bottom of the tank. The relationship between the depth of laser modification h1 and the depth of ultrasonic grinding h2 is: (h1-10)μm≤h2≤(h1-5)μm. When the boundary position is reached, the laser modification device switches to a Gaussian laser beam to perform laser modification on the corner area. At the same time, use the ultrasonic grinding device (5) to perform ultrasonic grinding to process microstructures in the corner area. The relationship between the depth of laser modification h1 and the depth of ultrasonic grinding h2 is: (h1-10)μm≤h2≤(h1-5)μm. Once the corner area is processed, the microstructure of the inner surface of the sealing groove is complete.

2. The method of claim 1, wherein the method further comprises: Specifically, S4 is: S4.1: Simultaneously start the laser modification device and the ultrasonic grinding device (5). According to the set processing path, use the laser modification device to generate a square laser beam to perform laser modification on the middle area of ​​the bottom of the tank. At the same time, use the ultrasonic grinding device (5) to perform ultrasonic grinding. The depth of laser modification is at least 5 μm greater than the depth of ultrasonic grinding in order to process microstructures in the middle area of ​​the bottom of the tank. The parameters of the square laser beam are: spot diameter 50 μm ~ 100 μm, vertical incidence, energy flux Φ = 2.0 J / cm² ~ 3.8 J / cm², and scanning speed 3 mm / s ~ 10 mm / s. S4.2: During the modification process in the middle area of ​​the tank bottom, the position parameters of the laser modification device are collected in real time. When it is determined that the laser modification device has reached the boundary position based on the position parameters of the laser modification device, the laser modification device is controlled to switch the square laser beam to a Gaussian laser beam and S4.3 is executed; otherwise, S4.1 is executed. S4.3: The corner area is modified by laser using a Gaussian laser beam, and ultrasonic grinding is performed simultaneously using an ultrasonic grinding device (5) in the corner area. The depth of laser modification is at least 5 μm greater than the depth of ultrasonic grinding in order to process microstructures in the corner area. The parameters of the Gaussian laser beam are: spot diameter 30 μm~60 μm, energy flux Φ= 1.5 J / cm²~2.5 J / cm², scanning speed 2 mm / s~8 mm / s. S4.4: During the corner area modification process, the position parameters of the laser modification device are collected in real time. When the corner area processing is completed according to the position parameters of the laser modification device, the laser modification device and the ultrasonic grinding device (5) are stopped to complete the processing of the microstructure on the inner surface of the sealing groove; otherwise, S4.3 is continued.

3. The method for fabricating microstructures on the inner surface of a sealing groove with partitioned adaptive laser waveforms according to claim 1 or 2, characterized in that, Synchronization time difference between the laser-modified device and the ultrasonic grinding device (5) seconds.

4. The method of claim 1 or 2, wherein the method is characterized by, The parameters of the ultrasonic grinding device (5) are: ultrasonic frequency 15 kHz - 40 kHz, ultrasonic amplitude 2 μm - 10 μm.

5. The method of claim 1, wherein, Make a cross-section along the depth direction of the sealing groove (8). Using the cross-section as a reference, take the midpoint of the bottom of the sealing groove (8) as the origin and the width direction of the bottom of the groove as the X direction. Determine the boundary position according to the following formula: In the formula, X is the demarcation position, unit: mm; W is the groove bottom width, unit: mm; is the distance between the demarcation position and the groove bottom edge, unit: mm.

6. The method for fabricating microstructures on the inner surface of a sealing groove with partitioned adaptive laser waveforms according to claim 2, characterized in that, The coverage length of the corner area is determined by the following formula: In the formula, R is the distance between the dividing point and the bottom edge of the tank, in mm; R is the radius of curvature of the corner, in mm. The laser compensation length is 0.01 mm to 0.05 mm.

7. The method for fabricating microstructures on the inner surface of a sealing groove with partitioned adaptive laser waveforms according to claim 2, characterized in that, When modifying the corner region, the incident angle of the Gaussian laser beam The relationship with the microstructure morphology of the inner surface of the sealing groove is as follows: In the formula, The angle of inclination of the inner wall of the sealing groove, in degrees; This is a correction factor, with a value range of 350° / mm to 500° / mm; Radius of curvature of the corner, unit: mm.

8. The method for fabricating microstructures on the inner surface of a sealing groove with partitioned adaptive laser waveforms according to claim 6 or 7, characterized in that, The relationship between the radius of curvature R of the turning angle and the width W of the groove bottom is: R≤W / 4.

9. A device for processing microstructures on the inner surface of a sealing groove with partitioned adaptive laser waveforms, used to implement the method for processing microstructures on the inner surface of a sealing groove with partitioned adaptive laser waveforms as described in claim 2, characterized in that, It includes laser modification devices, angle sensors (4), ultrasonic grinding devices (5), control systems (6), and positioning workpieces (7) and position sensors; The positioning workpiece (7) is used to fix the sealing groove (8) during processing; The position sensor is installed on the positioning workpiece (7) and connected to the control system signal to collect the position parameters of the laser modification device in real time during processing and send the position parameters to the control system (6). The angle sensor (4) is installed on the laser modification device and connected to the control system signal to collect the angle parameters of the laser modification device in real time and send the angle parameters to the control system (6). The control system (6) is electrically connected to the position sensor, angle sensor (4), ultrasonic grinding device (5), and laser modification device. The control system (6) is used to receive position parameters and angle parameters, and determine the processing position of the laser modification device according to the position parameters, and feed back the processing position to the ultrasonic grinding device (5) and the laser modification device. The control system (6) also adjusts the incident angle of the square laser beam or Gaussian laser beam according to the angle parameters. The laser modification device is used to perform laser modification on the middle area or corner area of ​​the bottom of the tank; The ultrasonic grinding device (5) is used to simultaneously perform ultrasonic grinding on the laser-modified area after the laser modification device has completed laser modification of the middle area or corner area of ​​the bottom of the groove. The laser modification depth is at least 5 μm greater than the ultrasonic grinding depth to process microstructures in the middle or corner areas of the groove bottom; the synchronization time difference between the laser modification device and the ultrasonic grinding device (5) Second.

10. The microstructure processing device for the inner surface of the sealing groove with partitioned adaptive laser waveform according to claim 9, characterized in that, The laser modification device includes a picosecond laser generator (1) and a DMD digital micromirror (2) and an optical imaging system (3) arranged sequentially along the laser emission direction. The DMD digital micromirror (2) is used to shape the laser generated by the picosecond laser generator (1) into a square laser beam or a Gaussian laser beam. The square laser beam is projected onto the middle area of ​​the bottom of the sealing groove (8) after passing through the optical imaging system (3) to perform laser modification on the middle area of ​​the bottom of the groove. The Gaussian laser beam is projected onto the corner area of ​​the sealing groove (8) after passing through the optical imaging system (3) to perform laser modification on the corner area.

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