A laser pretreatment device and method for transparent ceramic materials

Abstract

This invention discloses a laser pretreatment device and method for transparent ceramic materials, including a laser generator, a lens, a tube furnace, a ceramic sample holder, and a three-dimensional control support. The tube furnace includes a heating mechanism and a reaction tube, with the laser generator and lens correspondingly positioned at one end of the reaction tube. The three-dimensional control support is correspondingly positioned at the other end of the reaction tube, and the ceramic sample holder is fixedly connected to the movable end of the three-dimensional control support, extending into the reaction tube. The ceramic sample holder is equipped with a mounting base for holding the transparent ceramic sample, and a temperature sensor is located on the back side of the transparent ceramic sample. This invention can minimize the absorption and scattering of laser light by transparent ceramic materials. High-temperature heating of the transparent ceramic before laser pretreatment can improve the efficiency of laser pretreatment, increase the laser damage threshold, and also improve the surface hardness and flexural strength of the transparent ceramic.

Description

Technical Field

[0001] This invention relates to the field of optical material pretreatment technology, and in particular to a laser pretreatment device and method for transparent ceramic materials. Background Technology

[0002] Transparent ceramics, as a new generation of solid-state laser materials, possess unparalleled advantages over laser crystals and glass, serving as a paradigm of integrated structure and function in the field of ceramic materials research. Compared to single-crystal and glass materials, transparent ceramics offer significant advantages, including the ability to achieve high-concentration doping, flexible dimensions, composite structures, and short manufacturing cycles. An increasing number of transparent ceramic materials are being manufactured for laser emission, such as the DiPOLE100 at Rutherford Appleton Laboratory in the UK and Hamamatsu Photonics in Japan, both of which utilize transparent ceramics as laser gain media. However, research on laser damage to transparent ceramics is relatively limited compared to laser crystals, glass, and thin films. This is because: firstly, research on transparent ceramics as laser gain media started relatively late; secondly, as polycrystalline, transparent ceramics inevitably involve impurities and defects such as grain boundaries, micropores, and second phases during laser interaction, making the laser damage process and mechanism of transparent ceramics more complex and difficult to systematically and deeply explain and analyze. With the increasing application of transparent ceramics as gain media in high-power laser devices, research on the damage characteristics and performance improvement of transparent ceramics has become increasingly urgent.

[0003] Chinese patent CN116121685A discloses a "laser pretreatment process, high-bonding-performance ceramic coating, and preparation process." This laser pretreatment process includes the following steps: cleaning the substrate surface using a primary laser cleaning process; etching the cleaned substrate surface using a laser etching process; and cleaning the etched substrate surface using a secondary laser cleaning process. This laser pretreatment process involves pretreatment of the substrate surface through primary laser cleaning, laser etching, and secondary laser cleaning processes, which are interconnected and have a synergistic effect. However, this patented technology is only suitable for processing non-transparent ceramics. Transparent ceramics, as transparent optical materials, have much more stringent requirements for laser surface processing. Based on the inherent high light transmittance and densely distributed defect characteristics of transparent ceramic materials, there is an urgent need to develop a laser pretreatment device and method more suitable for transparent ceramics. Summary of the Invention

[0004] Technical problem to be solved: In view of the technical problems existing in the pretreatment process of transparent ceramic materials in the background art, the present invention provides a laser pretreatment device and method for transparent ceramic materials, which improves the damage threshold of transparent ceramic materials and enhances the laser damage resistance of transparent ceramics.

[0005] Technical solution: The present invention provides a laser pretreatment device for transparent ceramic materials, comprising a laser generator, a lens, a tube furnace, a ceramic sample holder, and a three-dimensional control support. The tubular furnace includes a heating mechanism and a reaction tube disposed within the heating mechanism, with the laser generator and lens correspondingly disposed at one end of the reaction tube. The three-dimensional control support is correspondingly set at the other end of the reaction tube, and the ceramic sample clamp is fixedly connected to the moving end of the three-dimensional control support, and the ceramic sample clamp extends into the reaction tube; The ceramic sample holder is provided with a mounting base for mounting transparent ceramic samples. A temperature sensor electrically connected to a temperature measuring cable is provided on the back side of the transparent ceramic sample on the mounting base. The back side of the mounting base is fixedly connected to the movable end of the three-dimensional control bracket.

[0006] This invention also discloses a laser pretreatment method for transparent ceramic materials, employing a laser pretreatment device, the laser pretreatment method comprising the following steps: Step S1: The transparent ceramic sample is ultrasonically cleaned in anhydrous ethanol to remove dust and oil stains from the surface. Then, the transparent ceramic sample is ultrasonically cleaned in deionized water to further remove impurities from the surface of the transparent ceramic sample. Step S2: Fix the cleaned transparent ceramic sample on the ceramic sample holder of the three-dimensional control support, place the ceramic sample holder in the reaction tube of the tube furnace for heating, set the heating temperature below the phase transition temperature of the transparent ceramic, monitor the heating temperature of the transparent ceramic sample in real time through the temperature sensor, and turn on the laser generator after the preset temperature is reached. Step S3: While heating the transparent ceramic sample, the position of the transparent ceramic sample is moved by the three-dimensional control support, and laser scanning is performed to achieve laser preprocessing of the transparent ceramic sample; Step S4: The laser-pretreated transparent ceramic sample is sequentially ultrasonically cleaned with anhydrous ethanol and deionized water to obtain transparent ceramic products.

[0007] Preferably, during the anhydrous ethanol ultrasonic cleaning in steps S1 and S4, the transparent ceramic sample is cleaned in stages using ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz, with each ultrasonic frequency requiring a cleaning time of 3 to 6 minutes.

[0008] Preferably, the ultrasonic cleaning in deionized water in steps S1 and S4 is divided into two ultrasonic cleaning cycles, using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz in sequence for one ultrasonic-assisted cleaning cycle, with each ultrasonic frequency having a cleaning time of 3 to 6 minutes; after one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated; after the last ultrasonic cleaning, the surface of the transparent ceramic sample is rinsed with flowing deionized water to remove residual moisture and particles.

[0009] Preferably, 5% to 50% H2O2 is added during the ultrasonic cleaning process of deionized water in steps S1 and S4.

[0010] Preferably, in step S3, during the laser scanning pretreatment of transparent ceramics, a suitable laser wavelength is selected to minimize the absorption and scattering of laser light by the transparent ceramic material.

[0011] Preferably, in step S3, the laser generator is a nanosecond-level pulsed laser generator with a laser power of 10~60W, a frequency of 10Hz, a scanning speed of 1000mm / s, a scanning number of 2~10 times, and a spot diameter of 1mm. During the laser scanning preprocessing, the position of the transparent ceramic sample is adjusted by a three-dimensional control support so that the superposition of the two scanning spots is 30~50%.

[0012] Beneficial effects: Compared with the prior art, the present invention has the following outstanding advantages: 1. As a transparent optical material, transparent ceramics have more stringent requirements for laser surface processing. Based on the inherent high light transmittance and densely distributed defects of transparent ceramic materials, there is an urgent need to develop a new laser pretreatment device and method that is more suitable for transparent ceramics. 2. This invention proposes a convenient, fast, and quality-controllable laser pretreatment method and a surface treatment method to improve the laser damage resistance of transparent ceramics. First, the transparent ceramics are ultrasonically cleaned in ethanol to remove surface dust and oil stains. Then, the transparent ceramics are ultrasonically cleaned in deionized water to further remove surface impurities. Subsequently, the cleaned transparent ceramics are heated in a tube furnace at a temperature below the ceramic phase transition temperature. The transparent ceramics are placed on a three-dimensional control support, allowing for easy movement of the ceramics during heating for laser scanning to achieve laser pretreatment. The temperature of the transparent ceramics is then measured in real-time using thermocouples connected to the side of the ceramics. Once the preset temperature is reached, the laser pretreatment system is activated. Finally, the laser-treated transparent ceramics are cleaned with deionized water and ethanol. 3. The laser pretreatment method of this invention selects a laser wavelength with high light transmittance for transparent ceramics, which can minimize the absorption and scattering of laser light by the transparent ceramic material. Before laser pretreatment, the transparent ceramic is heated to a preset temperature, approximately 300 degrees Celsius lower than the phase transition temperature of the transparent ceramic material. This improves the efficiency of laser pretreatment, increases the laser damage threshold, and also enhances the surface hardness and flexural strength of the transparent ceramic. Effective cleaning is performed before and after the laser pretreatment process to prevent the introduction of impurities and contaminants, maximizing the effectiveness of the laser pretreatment. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the transparent ceramic laser pretreatment device of the present invention; Figure 2 A graph showing the change in laser damage threshold before and after laser pretreatment of the transparent ceramic of the present invention; Figure 3 The results show the residual stress of the transparent ceramic after laser pretreatment according to the present invention. Figure 4 This refers to the surface roughness of the transparent ceramic before and after laser pretreatment according to the present invention.

[0014] Reference numerals: 1. Laser beam; 2. Lens; 3. Tube furnace; 31. Heating mechanism; 32. Reaction tube; 4. Ceramic sample holder; 5. Transparent ceramic sample; 6. Temperature sensor; 7. Temperature cable; 8. Three-dimensional control support. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will be described in conjunction with the accompanying drawings of the embodiments of the present invention. Figures 1-4 The technical solutions of the embodiments of the present invention will be clearly and completely described herein. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0016] like Figure 1As shown, a laser pretreatment device for transparent ceramic materials according to the present invention includes a laser generator, a lens 2, a tube furnace 3, a ceramic sample holder 4, and a three-dimensional control support 8. The laser generator is a nanosecond-level pulsed laser generator, which can emit a laser beam 1 of the required power and frequency as needed. The tube furnace 3 includes a heating mechanism 31 and a reaction tube 32 disposed within the heating mechanism 31. The laser generator and the lens 2 are respectively disposed at one end of the reaction tube 32. The laser beam 1 emitted by the laser generator enters the reaction tube 32 along the lens 2. The three-dimensional control bracket 8 is correspondingly set at the other end of the reaction tube 32. The ceramic sample clamp 4 is fixedly connected to the moving end of the three-dimensional control bracket 8 and extends into the reaction tube 32. The ceramic sample clamp 4 is provided with a mounting base for mounting the transparent ceramic sample 5. The mounting base is located on the back side of the transparent ceramic sample 5 and is provided with a temperature sensor 6 electrically connected to the temperature measuring cable 7. The temperature sensor 6 is electrically connected to an external display through the temperature measuring cable 7. The temperature of the transparent ceramic sample 5 can be displayed in real time through the display. The back side of the mounting base is fixedly connected to the moving end of the three-dimensional control bracket 8. The position of the mounting base in the reaction tube 32 can be adjusted in real time by the three-dimensional control bracket 8 to facilitate the adjustment of the interaction points between the transparent ceramic sample 5 and the laser beam 1.

[0017] This invention also discloses a laser pretreatment method for transparent ceramic materials, using a laser pretreatment device 100, the laser pretreatment method comprising the following steps: Step S1: The transparent ceramic sample 5 is ultrasonically cleaned in anhydrous ethanol to remove surface dust and oil stains. During the anhydrous ethanol ultrasonic cleaning, the transparent ceramic sample 5 is cleaned in stages using ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz, with a cleaning time of 3-6 minutes for each ultrasonic frequency. Then, the transparent ceramic sample 5 is ultrasonically cleaned in deionized water with 5%-50% H2O2 added. The ultrasonic cleaning in deionized water is divided into two ultrasonic cleaning cycles, using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz for one ultrasonic-assisted cleaning cycle, with a cleaning time of 3-6 minutes for each ultrasonic frequency. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated. After the last ultrasonic cleaning, the surface of the transparent ceramic sample 5 is rinsed with flowing deionized water to remove residual moisture and particles, further removing impurities from the surface of the transparent ceramic sample 5.

[0018] Step S2: Fix the cleaned transparent ceramic sample 5 on the ceramic sample holder 4 of the three-dimensional control support 8, place the ceramic sample holder 4 in the reaction tube 32 of the tube furnace for heating, set the heating temperature below the phase transition temperature of the transparent ceramic, monitor the heating temperature of the transparent ceramic sample 5 in real time through the temperature sensor 6, and turn on the laser generator after the preset temperature is reached.

[0019] Step S3: While heating the transparent ceramic sample 5, the position of the transparent ceramic sample 5 is moved by the three-dimensional control support 8 to perform laser scanning for laser pretreatment of the transparent ceramic sample 5. During the laser scanning pretreatment of the transparent ceramic, an appropriate laser wavelength is selected to minimize the absorption and scattering of the laser by the transparent ceramic material. A nanosecond-level pulsed laser generator is selected, with a laser power of 10~60W, a frequency of 10Hz, a scanning speed of 1000mm / s, 2~10 scans, and a spot diameter of 1mm. During the laser scanning pretreatment, the position of the transparent ceramic sample 5 is adjusted by the three-dimensional control support 8 so that the superposition of the two scanning spots is 30-50%.

[0020] Step S4: The pre-treated transparent ceramic sample 5 is subjected to ultrasonic cleaning with anhydrous ethanol and deionized water in sequence. During the anhydrous ethanol ultrasonic cleaning, ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz are used sequentially for staged cleaning of the transparent ceramic sample 5, with each ultrasonic frequency requiring 3–6 minutes of cleaning time. During the deionized water ultrasonic cleaning process, 5%–50% H2O2 is added. The ultrasonic cleaning in deionized water is divided into two ultrasonic cleaning cycles, using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz sequentially for one ultrasonic-assisted cleaning cycle, with each ultrasonic frequency requiring 3–6 minutes of cleaning time. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated. After the final ultrasonic cleaning, the surface of the transparent ceramic sample 5 is rinsed with flowing deionized water to remove residual moisture and particles.

[0021] Example 1: This invention also discloses a laser pretreatment method for transparent ceramic materials. In this example, the transparent ceramic sample 5 is a sheet-like structure made of Nd:YAG transparent ceramic material. The laser pretreatment method includes the following steps: Step S1: The transparent Nd:YAG ceramic sample 5 is ultrasonically cleaned in anhydrous ethanol to remove surface dust and oil stains. During the anhydrous ethanol ultrasonic cleaning, the transparent Nd:YAG ceramic sample 5 is cleaned in stages using ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz, with a cleaning time of 3 minutes for each ultrasonic frequency. Then, the transparent Nd:YAG ceramic sample 5 is ultrasonically cleaned in deionized water with 5% H2O2 added. The ultrasonic cleaning in deionized water is divided into two ultrasonic cleaning cycles, using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz for one ultrasonic-assisted cleaning cycle, with a cleaning time of 3 minutes for each ultrasonic frequency. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated. After the last ultrasonic cleaning, the surface of the transparent ceramic sample 5 is rinsed with flowing deionized water to remove residual moisture and particles, further removing impurities from the surface of the transparent Nd:YAG ceramic sample 5.

[0022] Step S2: Fix the cleaned Nd:YAG transparent ceramic sample 5 onto the ceramic sample holder 4 of the three-dimensional control support 8, place the ceramic sample holder 4 into the reaction tube 32 of the tube furnace for heating, set the heating temperature below the phase transition temperature of the transparent ceramic, monitor the heating temperature of the Nd:YAG transparent ceramic sample 5 in real time through the temperature sensor 6, and turn on the laser generator after the preset temperature is reached.

[0023] Step S3: While heating the transparent Nd:YAG ceramic sample 5, the position of the transparent Nd:YAG ceramic sample 5 is moved using the three-dimensional control support 8 to perform laser scanning for laser pretreatment of the transparent Nd:YAG ceramic sample 5. During the laser scanning pretreatment of the transparent ceramic, an appropriate laser wavelength is selected to minimize the absorption and scattering of the laser by the transparent ceramic material. Since the optical transmittance of the transparent Nd:YAG ceramic material is high at a wavelength of 1064nm, a laser wavelength of 1064nm is selected. A nanosecond-level pulsed laser generator is selected, with a laser power of 40W, a frequency of 10Hz, a scanning speed of 1000mm / s, 4 scans, and a spot diameter of 1mm. During the laser scanning pretreatment, the position of the transparent Nd:YAG ceramic sample 5 is adjusted using the three-dimensional control support 8 to ensure that the superposition of the two scanning spots is 30%.

[0024] Step S4: The Nd:YAG transparent ceramic sample 5, after laser pretreatment, is sequentially ultrasonically cleaned with anhydrous ethanol and deionized water. During anhydrous ethanol ultrasonic cleaning, ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz are used sequentially for staged cleaning of the Nd:YAG transparent ceramic sample 5, with a cleaning time of 3 minutes for each ultrasonic frequency. During deionized water ultrasonic cleaning, 5% H2O2 is added. Ultrasonic cleaning in deionized water is divided into two ultrasonic cleaning cycles, using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz sequentially for one ultrasonic-assisted cleaning cycle, with a cleaning time of 3 minutes for each ultrasonic frequency. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated. After the final ultrasonic cleaning, the surface of the Nd:YAG transparent ceramic sample 5 is rinsed with flowing deionized water to remove residual moisture and particles.

[0025] Example 2: This invention also discloses a laser pretreatment method for transparent ceramic materials. In this example, the transparent ceramic sample 5 is a sheet-like structure made of MgAl2O4 transparent ceramic material. The laser pretreatment method includes the following steps: Step S1: The transparent ceramic sample 5 of MgAl2O4 was ultrasonically cleaned in anhydrous ethanol to remove surface dust and oil stains. During the anhydrous ethanol ultrasonic cleaning, the transparent ceramic sample 5 of MgAl2O4 was cleaned in stages using ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz, with a cleaning time of 4 minutes for each ultrasonic frequency. Then, the transparent ceramic sample 5 of MgAl2O4 was ultrasonically cleaned in deionized water with 25% H2O2 added to remove the ions. The ultrasonic cleaning process in water is divided into two ultrasonic cleaning cycles. The ultrasonic-assisted cleaning cycles are performed sequentially at 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz, with each ultrasonic frequency lasting for 4 minutes. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated. After the last ultrasonic cleaning, the surface of the transparent MgAl2O4 ceramic sample 5 is rinsed with flowing deionized water to remove residual moisture and particles, further removing impurities from the surface of the transparent MgAl2O4 ceramic sample 5.

[0026] Step S2: Fix the cleaned transparent ceramic sample 5 of MgAl2O4 onto the ceramic sample holder 4 of the three-dimensional control support 8, place the ceramic sample holder 4 in the reaction tube 32 of the tube furnace for heating, and set the heating temperature below the phase transition temperature of transparent ceramic. Monitor the heating temperature of the transparent ceramic sample 5 of MgAl2O4 in real time through the temperature sensor 6. Turn on the laser generator after the preset temperature is reached.

[0027] Step S3: While heating the transparent ceramic sample 5 of MgAl2O4, the position of the transparent ceramic sample 5 of MgAl2O4 is moved by the three-dimensional control support 8 to perform laser scanning to achieve laser pretreatment of the transparent ceramic sample 5 of MgAl2O4. During the laser scanning pretreatment of the transparent ceramic, an appropriate laser wavelength is selected to minimize the absorption and scattering of laser by the transparent ceramic material. Since the optical transmittance of transparent ceramic of MgAl2O4 is as high as 87% at a wavelength of 1064nm, a laser wavelength of 1064nm is selected. A nanosecond-level pulsed laser generator is selected, with a laser power of 30W, a frequency of 10Hz, a scanning speed of 1000mm / s, 6 scans, and a spot diameter of 1mm. During the laser scanning pretreatment, the position of transparent ceramic sample 5 of MgAl2O4 is adjusted by the three-dimensional control support 8 so that the superposition of the two scanning spots is 40%.

[0028] Step S4: The pre-treated MgAl2O4 transparent ceramic sample 5 was sequentially ultrasonically cleaned with anhydrous ethanol and deionized water. During the anhydrous ethanol ultrasonic cleaning, ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz were used for staged cleaning, with each ultrasonic frequency lasting 4 minutes. During the deionized water ultrasonic cleaning, 25% H2O2 was added. The ultrasonic cleaning in deionized water was divided into two ultrasonic cleaning cycles, using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz for one ultrasonic-assisted cleaning cycle, with each ultrasonic frequency lasting 4 minutes. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank was replaced, and the above steps were repeated. After the final ultrasonic cleaning, the surface of the MgAl2O4 transparent ceramic sample 5 was rinsed with flowing deionized water to remove residual moisture and particles.

[0029] Example 3: This invention also discloses a laser pretreatment method for transparent ceramic materials. In this example, the transparent ceramic sample 5 is a sheet-like structure made of Nd:LuAG transparent ceramic material. The laser pretreatment method includes the following steps: Step S1: The transparent Nd:LuAG ceramic sample 5 is ultrasonically cleaned in anhydrous ethanol to remove surface dust and oil stains. During the anhydrous ethanol ultrasonic cleaning, the transparent Nd:LuAG ceramic sample 5 is cleaned in stages using ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz, with a cleaning time of 6 minutes for each ultrasonic frequency. Then, the transparent Nd:LuAG ceramic sample 5 is ultrasonically cleaned in deionized water with 50% H2O2 added. The ultrasonic cleaning in deionized water is divided into two ultrasonic cleaning cycles, using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz for one ultrasonic-assisted cleaning cycle, with a cleaning time of 6 minutes for each ultrasonic frequency. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated. After the last ultrasonic cleaning, the surface of the transparent Nd:LuAG ceramic sample 5 is rinsed with flowing deionized water to remove residual moisture and particles, further removing impurities from the surface of the transparent ceramic sample 5.

[0030] Step S2: Fix the cleaned Nd:LuAG transparent ceramic sample 5 onto the ceramic sample holder 4 of the three-dimensional control support 8, place the ceramic sample holder 4 into the reaction tube 32 of the tube furnace for heating, set the heating temperature below the phase transition temperature of the transparent ceramic, monitor the heating temperature of the Nd:LuAG transparent ceramic sample 5 in real time through the temperature sensor 6, and turn on the laser generator after the preset temperature is reached.

[0031] Step S3: While heating the transparent Nd:LuAG ceramic sample 5, the position of the transparent Nd:LuAG ceramic sample 5 is moved by the three-dimensional control support 8 to perform laser scanning for laser pretreatment of the transparent Nd:LuAG ceramic sample 5. During the laser scanning pretreatment of the transparent ceramic, an appropriate laser wavelength is selected to minimize the absorption and scattering of laser light by the transparent ceramic material. Since the optical transmittance of Nd:LuAG transparent ceramic at a wavelength of 1064nm is as high as 84%, a laser wavelength of 1064nm is selected. A nanosecond-level pulsed laser generator is selected, with a laser power of 25W, a frequency of 10Hz, a scanning speed of 1000mm / s, 10 scans, and a spot diameter of 1mm. During the laser scanning pretreatment, the position of the transparent Nd:LuAG ceramic sample 5 is adjusted by the three-dimensional control support 8 to ensure that the superposition of the two scanning spots is 50%.

[0032] Step S4: The Nd:LuAG transparent ceramic sample 5, after laser pretreatment, is sequentially ultrasonically cleaned with anhydrous ethanol and deionized water. During anhydrous ethanol ultrasonic cleaning, the Nd:LuAG transparent ceramic sample 5 is cleaned in stages using ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz, with each ultrasonic frequency lasting 6 minutes. During deionized water ultrasonic cleaning, 50% H2O2 is added. Ultrasonic cleaning in deionized water is divided into two ultrasonic cleaning cycles, using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz sequentially for one ultrasonic-assisted cleaning cycle, with each ultrasonic frequency lasting 6 minutes. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated. After the final ultrasonic cleaning, the surface of the Nd:LuAG transparent ceramic sample 5 is rinsed with flowing deionized water to remove residual moisture and particles.

[0033] The laser pretreatment methods in Embodiments 1-3 of this invention employ laser wavelengths with high light transmittance suitable for transparent ceramics, thereby minimizing laser absorption and scattering by the transparent ceramic material. Prior to laser pretreatment, the transparent ceramic is heated to a preset temperature approximately 300 degrees Celsius below its phase transition temperature. This improves the efficiency of laser pretreatment, increases the laser damage threshold, and enhances the surface hardness and flexural strength of the transparent ceramic. Effective cleaning is performed both before and after laser pretreatment to prevent the introduction of impurities and contaminants, maximizing the effectiveness of the laser pretreatment.

[0034] like Figure 2 As shown in the figure, the change in laser damage threshold of the transparent ceramic sample 5 of MgAl2O4 before and after laser pretreatment in Example 2 of the present invention is illustrated by... Figure 2 It can be seen that the laser damage threshold of the transparent MgAl2O4 ceramic sample 5 is significantly improved after laser pretreatment. Under single-scan pretreatment, the energy density of the pulsed laser is changed, and the laser energy density is continuously increased from 2.24 J / cm². 2 Up to 8.96 J / cm 2 During the process, the laser damage threshold of the transparent MgAl2O4 ceramic sample was significantly improved. Under the multi-scan system, with the energy density of the stable laser remaining constant, continuously increasing the number of scans for laser pretreatment had a significant positive effect on reducing the laser damage threshold, until the laser damage threshold tended to stabilize after 7 scans.

[0035] like Figure 3As shown, the test results of the residual stress of the transparent ceramic sample of Nd:LuAG after laser pretreatment in Example 3 of the present invention are obtained from... Figure 3 It can be seen that the residual stress of the transparent Nd:LuAG ceramic without laser pretreatment is 2.84 N / m. 2 After a single laser scan, the residual stress of the Nd:LuAG transparent ceramic was 2.16 N / m². After five laser scans, the residual stress of the Nd:LuAG transparent ceramic was 0.80 N / m². 2 Test results show that this surface pretreatment method for improving the laser damage resistance of transparent ceramics can effectively reduce the residual stress of transparent ceramics, which is a potential mechanism for improving the laser damage threshold.

[0036] like Figure 4 As shown, the surface roughness test results of the Nd:LuAG transparent ceramic after laser pretreatment in Embodiment 3 of the present invention are obtained from... Figure 4 It can be seen that the surface roughness Ra of the transparent Nd:LuAG ceramic without laser pretreatment is 7.6 nm; after 7 laser scans, the surface roughness of the transparent Nd:LuAG ceramic is 4.3 nm.

[0037] The above are preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A laser pretreatment method for transparent ceramic materials, characterized in that, Includes a laser generator, a lens (2), a tube furnace (3), a ceramic sample holder (4), and a three-dimensional control support (8); The tubular furnace (3) includes a heating mechanism (31) and a reaction tube (32) disposed within the heating mechanism (31). The laser generator and lens (2) are respectively disposed at one end of the reaction tube (32). The three-dimensional control support (8) is correspondingly set at the other end of the reaction tube (32), and the ceramic sample clamp (4) is fixedly connected to the moving end of the three-dimensional control support (8), and the ceramic sample clamp (4) extends into the reaction tube (32). The ceramic sample clamp (4) is provided with a mounting base for mounting a transparent ceramic sample (5). The mounting base is located on the back side of the transparent ceramic sample (5) and is provided with a temperature sensor (6) electrically connected to a temperature measuring cable (7). The back side of the mounting base is fixedly connected to the movable end of the three-dimensional control bracket (8). The laser pretreatment method includes the following steps: Step S1: The transparent ceramic sample (5) is ultrasonically cleaned in anhydrous ethanol to remove dust and oil stains from the surface. Then, the transparent ceramic sample (5) is ultrasonically cleaned in deionized water to further remove impurities from the surface of the transparent ceramic sample (5). Step S2: Fix the cleaned transparent ceramic sample (5) on the ceramic sample holder (4) of the three-dimensional control support (8), place the ceramic sample holder (4) in the reaction tube (32) of the tube furnace for heating, set the heating temperature below the phase transition temperature of the transparent ceramic, monitor the heating temperature of the transparent ceramic sample (5) in real time through the temperature sensor (6), and turn on the laser generator after the preset temperature is reached. Step S3: While heating the transparent ceramic sample (5), the position of the transparent ceramic sample (5) is moved by the three-dimensional control support (8), and laser scanning is performed to achieve laser pretreatment of the transparent ceramic sample (5); the laser generator is a nanosecond pulse laser generator with a laser power of 10~60W, a frequency of 10Hz, a scanning speed of 1000mm / s, a scanning number of 2~10 times, and a spot diameter of 1mm; during the laser scanning pretreatment process, the position of the transparent ceramic sample (5) is adjusted by the three-dimensional control support (8) so that the superposition of the two scanning spots is 30~50%; Step S4: The transparent ceramic sample (5) after laser pretreatment is ultrasonically cleaned with anhydrous ethanol and deionized water in sequence to obtain transparent ceramic products.

2. The laser pretreatment method for transparent ceramic materials according to claim 1, characterized in that, In steps S1 and S4, during the ultrasonic cleaning with anhydrous ethanol, the transparent ceramic sample (5) was cleaned in stages using ultrasonic frequencies of 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz, with each ultrasonic frequency requiring a cleaning time of 3 to 6 minutes.

3. The laser pretreatment method for transparent ceramic materials according to claim 2, characterized in that, In steps S1 and S4, ultrasonic cleaning in deionized water is divided into two ultrasonic cleaning cycles. One ultrasonic-assisted cleaning cycle is performed sequentially using 15kHz, 24kHz, 41kHz, 56kHz, 78kHz, 90kHz, and 115kHz. The cleaning time for each ultrasonic frequency is 3 to 6 minutes. After one ultrasonic cleaning cycle, the deionized water in the rinsing tank is replaced, and the above steps are repeated. After the last ultrasonic cleaning, the surface of the transparent ceramic sample (5) is rinsed with flowing deionized water to remove residual moisture and particles.

4. The laser pretreatment method for transparent ceramic materials according to claim 3, characterized in that, In steps S1 and S4, 5% to 50% H2O2 is added during the ultrasonic cleaning process with deionized water.

5. The laser pretreatment method for transparent ceramic materials according to claim 1, characterized in that, In step S3, during the laser scanning pretreatment of transparent ceramics, a suitable laser wavelength is selected to minimize the absorption and scattering of laser light by the transparent ceramic material.

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