A method for processing micro-holes of a ceramic workpiece

Abstract

The present application relates to the technical field of ceramics, and particularly relates to a ceramic workpiece micro-hole processing method, comprising the following steps: processing preparation stage, positioning and marking, pretreatment, selecting a suitable laser, fine processing, and post-treatment. The method has the following three advantages: first, laser cutting technology can realize high-precision processing of the inner wall of the ceramic, and can process high-precision, small-size micro-holes and air channels, thereby improving the performance and quality of the ceramic product; second, the laser cutting technology has a high processing speed, which is 1000% faster than the traditional process CNC, effectively improves the production efficiency of the ceramic product, reduces the labor cost, and the present application does not need to use tools such as a micro-hole processing cutter grinding head, which is conducive to reducing the processing cost; third, the processing method can be applied to ceramic products of different materials, different sizes and different shapes, and has a wide application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of ceramics, and in particular to a method for processing micro-holes in a ceramic workpiece. Background Art

[0002] Ceramics are a type of material that performs well in high-temperature environments and are widely used in aerospace, chemical, energy and other fields. Ceramic materials have been widely used in modern industry, especially in high-temperature environments, such as aerospace, chemical, energy and other fields. With the continuous development of science and technology, the performance and quality requirements of ceramic materials are getting higher and higher. In the production process of ceramic products, the role of micro-airways on the inner wall of ceramics is very important. It can affect the performance and quality of ceramic products by controlling the gas flow inside the ceramics. For example, in ceramic engines, micro-airways can affect combustion efficiency and power output, thereby improving the efficiency of the engine. Therefore, the processing of micro-airways on the inner wall of ceramics is one of the important links in the production of ceramic products, and the design and manufacture of micro-airways on the inner wall of ceramics has become one of the research hotspots.

[0003] The machining of micro-gas grooves is a key step in the fabrication of micro-airways on ceramic inner walls. Its precision and efficiency directly impact the quality and performance of the entire ceramic product. While research into the machining of micro-gas grooves on ceramic inner walls has yielded some results, many challenges remain.

[0004] At present, there are mainly the following methods for processing micro airways on the inner wall of ceramics at home and abroad:

[0005] 1. Processing method based on chemical etching

[0006] Chemical etching is a common processing method that can remove a layer of material from the ceramic surface through chemical reactions. However, this method has low processing accuracy and cannot produce high-precision, small-sized micro airways.

[0007] 2. Machining-based processing methods

[0008] Machining is a method of removing material using a CNC machine with an electroplated grinding head. This method offers high precision and can produce high-precision, small-sized micro airways. However, this method is slow and expensive. Summary of the Invention

[0009] To overcome at least one of the following deficiencies of existing methods for machining micro-airways in ceramic inner walls: 1) low machining accuracy; 2) slow machining speed; and 3) high cost, the present invention provides a method for machining micro-holes in ceramic workpieces based on high-precision machining technology. This method can process both micro-airways and micro-holes in ceramic inner walls. This method utilizes laser cutting technology to precisely machine the inner wall of the ceramic by controlling the accuracy and speed of the laser beam, resulting in micro-air slots and micro-holes of varying shapes, sizes, and quantities.

[0010] The purpose of the present invention is achieved through the following technical solution: a method for processing micro-holes in a ceramic workpiece, the method comprising the following steps:

[0011] Step 1: Processing preparation stage

[0012] Before you begin, you need to prepare the ceramic sample workpiece to be processed and make sure its surface is clean and free of stains.

[0013] Step 2: Positioning and marking

[0014] Computer-aided design software is used to draw the shape and position of the required microholes, and then a laser system is used for precise marking.

[0015] The choice of micropore shape and position depends on the specific application scenario and design purpose. The shape of the micropore may need to consider its compatibility with subsequent functions, such as whether it is conducive to fluid flow, whether it meets specific optical or mechanical performance requirements, etc. The choice of micropore position may need to consider the stability of the overall structure, coordination with other components, and whether the optimal functional effect can be achieved.

[0016] After marking is completed, micropores that match the designed shape will appear on the ceramic sample. These micropores have high precision and clarity, relatively neat edges, and a certain depth and surface characteristics. The specific effects and characteristics will also vary depending on the laser parameters and the properties of the ceramic material.

[0017] Step 3: Preprocessing

[0018] Pre-treat the area of ​​the ceramic sample's inner wall that will be irradiated to remove surface contaminants. Appropriate pre-treatment of the area to be irradiated, including the removal of surface contaminants, can improve processing efficiency and quality. After pre-treatment, the surface of the ceramic sample is cleaner and free of contaminants, which facilitates the smooth progress of subsequent processing and improves processing quality. The changes in the surface properties of the ceramic sample can make the ceramic sample easier to process in subsequent processing, improve bonding with other materials, and enhance optical properties. Pre-treatment can also improve processing efficiency because a clean surface and appropriate surface properties can reduce obstacles and problems during processing.

[0019] Step 4: Choose the right laser

[0020] Select the appropriate type of laser based on the processing requirements and adjust the laser power. The laser can be a ceramic laser. The power also needs to be adjusted appropriately. After repeated experiments, the inventors have determined that the optimal laser power is 5W-10W. Too high a power can easily lead to overheating, while too low a power cannot meet the processing requirements.

[0021] Step 5: Fine processing

[0022] The pulse mode is used to reduce the heat-affected zone, and the processing effect is continuously monitored and the parameters are fine-tuned during the process.

[0023] Step 6: Post-processing

[0024] After laser processing, the workpiece should be further cleaned to remove residues and ensure the cleanliness of the workpiece surface. After laser processing, the workpiece should be further cleaned to remove residues and check whether polishing or other subsequent processing is necessary.

[0025] Preferably, in step 1, the ceramic sample workpiece is prepared as follows:

[0026] Step 1, ingredients: accurately weigh various raw materials according to the required chemical composition;

[0027] Step 2, mixing: mix the raw materials thoroughly;

[0028] Step 3: Molding: Dry pressing, grouting, and other methods can be used, and the corresponding pressure, mold and other parameters can be set according to specific requirements;

[0029] Step 4, drying: Drying under appropriate temperature and humidity conditions to remove moisture;

[0030] Step 5, sintering: sintering is carried out in a high-temperature furnace, and appropriate process parameters such as sintering temperature, heating rate, and holding time are set to obtain the required ceramic properties and structure.

[0031] The ceramic samples are advanced ceramic materials such as alumina, silicon nitride, and silicon carbide produced by our unit. The specific raw materials, dosage, and related production parameters will not be repeated here.

[0032] Alumina ceramics have extremely high hardness (HRA90-93), excellent electrical insulation (1x10^-14 to 1x10^15 Ωcm), moderate to very high mechanical strength (360-600 MPa), extremely high compressive strength (2250-2700 MPa), low thermal conductivity (25-32 W / mK), and a maximum operating temperature of 1400°C. Alumina (Al2O3) boasts high hardness, excellent wear resistance, corrosion resistance, and high-temperature resistance, making it suitable for various industries such as machinery, molds, textiles, oil, chemicals, refractories, and electronics. It is currently the most widely used and largest-volume wear-resistant and high-temperature resistant oxide ceramic. The main alumina ceramic grades in Xiayang, Guangdong include A-100, A-200, and AZ-100.

[0033] Silicon carbide ceramics have an extremely low density (3.20g / cm 3 ), extremely high hardness (94HRA), high thermal conductivity (80W / mK), low linear expansion coefficient (4.5x10-6 / K at 400°C), and a maximum operating temperature of 1500°C, maintaining excellent corrosion and wear resistance even at high temperatures. Silicon carbide is one of the hardest materials in the fine ceramic family, with a hardness approaching that of diamond. Not only is it the lightest, it also possesses excellent thermal conductivity, high-temperature chemical stability, low thermal expansion, and extreme acid and alkali resistance. Therefore, silicon carbide is an excellent material for kiln furniture, furnaces, and high-temperature wear-resistant parts. Its outstanding resistance to corrosion, wear, and erosion is matched only by its ability to withstand friction and wear.

[0034] Silicon nitride ceramics have extremely high hardness (92.5HRA), excellent fracture toughness (6-7.0MPam1 / 2), good bending strength (850MPa), and extremely low density (3.20g / cm 3 ), an extremely low coefficient of thermal expansion (3.2x10-6 / K), and a maximum operating temperature of 1400°C. Silicon nitride (S3N4) possesses an exceptional combination of material properties. Its low density yet exceptional hardness, coupled with its unique crystal structure, imparts exceptional thermal stability and high fracture toughness, making it a durable choice for use under extreme conditions. Therefore, silicon nitride ceramics are the undisputed choice for high-speed, high-precision bearings, as well as a crucial material for high-temperature forming, high-speed tooling, and high-temperature wear-resistant parts.

[0035] Preferably, step 2 of positioning marking specifically involves: setting parameters based on the graphical data drawn in CAD software; adjusting parameters such as laser power and focal length to ensure accurate marking; and activating the laser system to mark the ceramic sample according to the preset path and parameters, resulting in micropores on the ceramic sample that conform to the designed shape. There are many manufacturers and product models of laser systems, and different manufacturers and models may be selected for different applications. Han's Laser is a common example.

[0036] Preferably, in the third step, the pre-treatment method is a low-power scanning method or a method of adding specific chemical agents to change the surface layer properties.

[0037] Specifically, the low-power scanning method specifically refers to using a relatively low-power laser energy beam to slowly and carefully scan the surface of the area to be irradiated. By scanning with a low-power energy beam, the combination of contaminants with the workpiece surface is weakened or destroyed, thereby achieving the purpose of separating and removing the contaminants from the workpiece surface.

[0038] The method of adding specific chemical agents to change the surface layer properties of the workpiece surface specifically refers to selecting appropriate chemical agents according to the processing requirements and material properties and applying them to the surface. The purpose is to change the physical and chemical properties of the surface layer through the reaction or action of the chemical agents with the workpiece surface, which is beneficial to increasing the activity of the surface, improving the wettability of the surface, enhancing the compatibility of the surface with the subsequent processing process, etc.

[0039] Specifically, the chemical agent can be hydrofluoric acid (concentration about 5%-10%) for etching ceramic surfaces to increase their roughness and activity; or nitric acid (concentration about 10%-20%) for treating ceramic surfaces to improve their wettability. The reason for choosing these chemical agents is that they can react or act with the workpiece surface in a specific way, thereby changing the physical and chemical properties of the surface layer to achieve the purpose of increasing the activity of the surface, improving the wettability, and enhancing the compatibility.

[0040] Preferably, in the fourth step, the laser power is 5-10W, and the laser is a Nd:YAG ceramic laser with a wavelength of 850nm-1064nm. Within the wavelength range of 850nm-1064nm, it can better interact with the processed material, improving the processing efficiency and precision. Wavelength below 850nm may result in insufficient energy absorption, poor processing effect; wavelength exceeding 1064nm may cause excessive energy concentration, causing unnecessary damage to the material. Compared with other lasers, Nd:YAG ceramic laser has higher stability and reliability, can provide stable laser output, and ensure the consistency of processing quality. At the same time, its application in industrial processing is more mature, and the technology is relatively perfect.

[0041] Preferably, the fifth step of fine processing specifically refers to setting the pulse frequency and pulse width parameters of the laser according to the material properties and processing precision requirements to minimize the heat-affected zone while ensuring the processing quality. In actual operation, it is necessary to find the most suitable specific parameter combination through multiple tests and experience accumulation. The surface quality and dimensional accuracy of the processing effect are closely observed, and the parameters are adjusted and optimized in a timely manner.

[0042] If the surface quality is not up to standard, the parameters of the three aspects need to be adjusted:

[0043] 1. Laser power: Too high power may cause excessive melting or evaporation of the material, increasing surface roughness; too low power may result in insufficient processing and also affect the surface quality;

[0044] 2. Pulse width: A wider pulse width may cause more heat accumulation, resulting in worse surface roughness; a narrower pulse width can reduce the heat impact and make the surface smoother;

[0045] 3. Scanning speed: If the scanning speed is too fast, the material will not have enough time to fully react, which may cause an uneven surface; if the speed is too slow, it may generate too much heat.

[0046] If the dimensional accuracy is not high enough, four parameters need to be adjusted:

[0047] 1. Spot diameter: The smaller the spot diameter, the higher the processing accuracy;

[0048] 2. Positioning accuracy: The accuracy of the equipment's positioning system directly affects the accuracy of the processing position;

[0049] 3. Repeat positioning accuracy: The consistency of position during repeated processing has an important impact on accuracy;

[0050] 4. Pulse frequency: Appropriate pulse frequency helps improve processing accuracy.

[0051] Preferably, in step five, the short pulse width is 1-3 μs, the high pulse frequency is 5-10 kHz, the scanning speed is 80-100 mm / s, and the focal length of the focusing lens is 40-60 mm. Preferably, the focal length of the focusing lens is 50 mm.

[0052] If the heat-affected zone is large, defects such as material deformation, microstructural changes, and increased residual stress may occur, affecting material performance and service life. This solution, through reasonable parameter settings, can control the heat-affected zone to a smaller range. The specific range will be affected by various factors, such as material properties and processing requirements, but it can generally effectively reduce the heat-affected zone and improve processing quality.

[0053] Preferably, the post-processing in step six is ​​to use appropriate tools or methods to clean away debris, particles and other substances generated by laser processing remaining on the surface of the workpiece.

[0054] Use appropriate tools or methods, such as continuously blowing the product with a multi-directional high-pressure air gun. First, the product can be cooled down. Second, the debris, particles and other substances remaining on the surface of the workpiece generated by laser processing can be blown away without affecting the processing of subsequent products.

[0055] Preferably, after the post-processing in step six, step seven is also included, polishing or coating treatment, wherein the polishing treatment is to polish the inner wall of the ceramic sample by mechanical polishing or chemical polishing to improve the surface finish of the workpiece; and spray Teflon coating on the inner wall of the ceramic sample to improve the surface strength of the workpiece.

[0056] After post-processing, according to the roughness requirements of the workpiece surface: if a higher smoothness is required, and the workpiece surface has obvious flaws, scratches, etc., polishing is required, and better workpiece surface flatness is required to meet specific functions.

[0057] There are many ways to polish, the most common ones are mechanical polishing (using tools such as polishing wheels) and chemical polishing. The specific requirements depend on factors such as the material, shape, size of the workpiece and the polishing effect to be achieved. Mechanical polishing is generally chosen.

[0058] While ensuring that the workpiece size meets the requirements, coating strengthening treatment is performed on the workpiece surface, such as spraying Teflon coating, which is beneficial to improving the strength of the workpiece surface.

[0059] This invention uses laser cutting technology to create micro-air channels on the inner wall of ceramics. Specifically, a ceramic sample is first prepared and then processed using a laser cutter. During the processing, by adjusting and controlling the laser beam, micro-air channels of varying shapes, sizes, and quantities can be created on the inner wall of the ceramic. To verify the feasibility and superiority of this method, a comparative experiment was conducted against traditional processing methods, and the processing results were measured and analyzed.

[0060] Compared with traditional processing methods, the method of the present invention has the advantages of high processing precision, high speed, low cost, etc., can improve the performance and quality of ceramic products, and has broad application prospects.

[0061] The beneficial effects of the present invention are:

[0062] Compared with traditional processing methods, the method of the present invention has the following three advantages:

[0063] 1) High processing precision: The laser cutting technology of the present invention can achieve high-precision processing of the inner wall of ceramics, and can process micro holes and air channels with high precision (tolerance of ±0.03-0.05mm), small size (micro hole diameter φ0.25-0.5mm), and micro hole depth of 5-10mm, thereby improving the performance and quality of ceramic products;

[0064] 2) Fast speed and low cost: Laser cutting technology has a fast processing speed, which is 1000% faster than traditional CNC technology. It effectively improves the production efficiency of ceramic products and reduces labor costs. In addition, this application does not require the use of tools such as tool grinding heads for processing micro holes, which is conducive to reducing processing costs.

[0065] 3) Wide range of applications: The processing method proposed in the present invention can be applied to ceramic products of different materials, sizes and shapes, and has a wide range of application prospects.

[0066] Specifically, ceramic products are made of materials such as alumina, silicon nitride, and silicon carbide. Sizes range from microscopic ceramic products measuring a few millimeters, such as micro ceramic gas-permeable discs, to larger ceramic components measuring tens of centimeters or even larger, such as large ceramic robotic arms. The process is suitable for regularly shaped ceramic products, such as round, rectangular, and square, as well as irregularly shaped products, such as uniquely shaped ceramic mechanical parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 Schematic diagram of the microporous structure of the alumina porous ceramic disk of Example 1 of the present invention.

[0068] Figure 2 Schematic diagram of the microporous structure of the alumina robotic arm of Example 2 of the present invention.

[0069] Figure 3 Schematic diagram of the micropore structure of the silicon carbide robotic arm of Example 3 of the present invention.

[0070] Figure 4 Schematic diagram of the microporous structure of the silicon carbide triangular bracket of Example 4 of the present invention.

[0071] Figure 5 Schematic diagram of the micro airway structure of the silicon carbide air floatation gauge of Example 5 of the present invention. DETAILED DESCRIPTION

[0072] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the examples, and the contents of the embodiments are not intended to limit the present invention. In the following examples, unless otherwise specified, the raw materials or processing techniques used are conventional commercially available raw materials or conventional processing techniques in the art.

[0073] Example 1

[0074] A method for machining micro-holes in a ceramic workpiece comprises the following steps:

[0075] Step 1: Processing preparation stage: Before starting, you need to prepare the ceramic sample workpiece to be processed (alumina porous ceramic disk) and ensure that its surface is clean and free of stains.

[0076] Step 2: Positioning and Marking: Use computer-aided design software to draw the desired micropore shape and location, then use a laser system for precise marking. Specifically, set parameters based on the graphical data drawn in the CAD software; adjust laser power to 7W and focal length to 50mm to ensure accurate marking. Start the laser system and mark the ceramic sample according to the preset path and parameters, resulting in micropores that match the designed shape.

[0077] Step 3. Pretreatment: Pretreat the area of ​​the ceramic sample workpiece to be irradiated to remove contaminants on the surface; the pretreatment method is to use a low-power scanning method or add specific chemicals to change the surface properties. The low-power scanning method specifically refers to using a relatively low-power laser energy beam to scan the surface of the area to be irradiated.

[0078] Step 4. Select a suitable laser: Select the appropriate type of laser according to the processing requirements and adjust the laser power; the laser power is 7W, and the laser is a Nd:YAG ceramic laser with a wavelength of 957nm.

[0079] Step 5: Fine Machining: Based on the material properties and machining accuracy requirements, the laser's pulse frequency and pulse width parameters are set to minimize the heat-affected zone. The surface quality and dimensional accuracy of the machining process are closely monitored, and the parameters are finely adjusted and optimized in a timely manner. Specifically, the short pulse width is 2μs, the high pulse frequency is 7kHz, the scanning speed is 90mm / s, and the focusing lens focal length is 50mm.

[0080] Specifically, in step 1, the preparation method of the ceramic sample workpiece is as follows: Step 1, batching: accurately weigh various raw materials according to the required chemical composition; Step 2, mixing: fully and evenly mix the raw materials; Step 3, molding: dry pressing molding, slip injection molding and other methods can be used, and the corresponding pressure, mold and other parameters are set according to specific requirements; Step 4, drying: drying under appropriate temperature and humidity conditions to remove moisture; Step 5, sintering: sintering in a high-temperature furnace, setting appropriate process parameters such as sintering temperature, heating rate, and holding time to obtain the required ceramic properties and structure.

[0081] like Figure 1 As shown in the figure, the micro-hole processing of the alumina ceramic disk was successfully achieved under this setting. The diameter of the ceramic disk was D110 mm, the micro-hole processing time was 90 minutes, the number of micro-holes on the ceramic disk was 97, the diameter of each micro-hole was about 250 μm and the depth was about 100 μm. The micro-holes of the alumina porous ceramic disk had no cracks and the incisions were fine.

[0082] Example 2

[0083] The difference between this embodiment and Example 1 is that: in this actual operation, a Nd:YAG ceramic laser with a wavelength of 850nm was used to perform micro-hole processing on the ceramic workpiece of the alumina robotic arm. After repeated experiments, the optimal process conditions were obtained as follows: laser power 5W, short pulse width 3μs, high pulse frequency 10kHz, scanning speed 100mm / s, and focusing lens focal length 40mm.

[0084] like Figure 2 As shown in the figure, under this setting, the micro-hole processing of the crack-free alumina robot arm with a diameter of 2000μm and a depth of 3000μm was successfully achieved. The overall dimensions of the ceramic robot arm are 300mm*90mm*5mm, the processing time is 60 minutes, and the number of micro-holes on the alumina robot arm is 42 with a diameter of 2000μm±0.03mm.

[0085] Example 3

[0086] The difference between this embodiment and Example 1 is that: in this actual operation, a Nd:YAG ceramic laser with a wavelength of 850nm was used to perform micro-hole processing on the ceramic workpiece of the silicon carbide robotic arm. After repeated experiments, the optimal process conditions were obtained as follows: laser power 8W, short pulse width 2μs, high pulse frequency 8kHz, scanning speed 100mm / s, and focusing lens focal length 50mm.

[0087] like Figure 3 As shown in the figure, under this setting, a crack-free micro-hole machining of a silicon carbide workpiece with a diameter of 5mm and a depth of 5mm was successfully achieved using a robot arm. The dimensions of the robot arm are 300mm*80mm*5, and the required machining time is 15 minutes. The number of micro-holes on the silicon carbide ceramic workpiece is 3.

[0088] Example 4

[0089] The difference between this embodiment and Example 1 is that: in this actual operation, a Nd:YAG ceramic laser with a wavelength of 1064nm was used to perform micro-hole processing on the ceramic workpiece of the silicon carbide tripod bracket. After repeated experiments, the optimal process conditions were obtained as follows: laser power 10W, short pulse width 1μs, high pulse frequency 5kHz, scanning speed 80mm / s, and focusing lens focal length 60mm.

[0090] like Figure 4 As shown in the figure, under this setting, a crack-free micro-hole machining of a silicon carbide triangular bracket with a diameter of 1000μm and a depth of 5mm was successfully achieved. The dimensions of the silicon carbide triangular bracket are 135mm*135mm*10mm, and the required machining time is 45 minutes. The number of micro-holes on the ceramic workpiece is 21 with a diameter of 1.0mm.

[0091] Example 5

[0092] The difference between this embodiment and Example 1 is that: in this actual operation, a Nd:YAG ceramic laser with a wavelength of 850nm-1064nm was used to perform micro-airway processing on the ceramic workpiece of the silicon carbide air floatation gauge. After repeated experiments, the optimal process conditions were obtained as follows: laser power 5-10W, short pulse width 1-2μs, high pulse frequency 5-10kHz, scanning speed 80-100mm / s, and focusing lens focal length 50mm.

[0093] Under this setting, we successfully achieved the micro-airway machining of a crack-free silicon carbide air float gauge with a width of 0.25mm, a length of 6mm, and a depth of 0.1mm. The dimensions of the ceramic workpiece of the silicon carbide air float gauge are an outer diameter of D12.5mm, an inner diameter of D8mm, and a total length of 38mm. The required machining time is 30 minutes, and the number of micro-airways on the ceramic workpiece is 4. At the same time, 4 φ0.3±0.025mm micro-holes were achieved, such as Figure 5 shown.

[0094] Example 6

[0095] This embodiment differs from Examples 1-5 in that it also includes Step 6, Post-Processing: Further cleaning of the laser-finished workpiece to remove debris and ensure a clean surface. Specifically, appropriate tools or methods are used to remove debris, particulate matter, and other substances remaining on the workpiece surface resulting from laser processing. The remainder of this embodiment is identical to Examples 1-5 and will not be further elaborated here.

[0096] Comparative Example 1

[0097] Using traditional CNC technology, for example, it takes 16 hours to produce 97 evenly spaced micro-holes measuring 0.25 ± 0.03 mm. Furthermore, a single diamond electroplated grinding head can only produce a maximum of three micro-holes before the electroplating layer peels off, necessitating a timely tool change to continue machining. Otherwise, not only will the micro-holes fail to meet the required dimensions, but the tool may also burn, leading to chipping and cracking in the ceramic. This significantly increases processing and material costs, and creates a high risk of scrap.

[0098] Comparative Example 2

[0099] Fiber lasers are suitable for industrial metal cutting, such as sheet metal cutting, where they achieve high precision and high speed. TRUMPF fiber lasers can cut a wide range of metals, from thin sheets to medium-thick plates, such as stainless steel and carbon steel. However, they cannot achieve the same performance in ceramics as metal processing, and are unable to produce micro-holes as small as 0.3 ± 0.03 mm in diameter.

[0100] The performance comparison of the micro holes / air passages of the ceramic workpieces prepared in Examples 1-5 and Comparative Examples 1-2 shows that the micro holes / air passages with small size (micro hole diameter φ 0.25-0.5 mm) can be machined, the machining precision is high (tolerance is ±0.03-0.05 mm), the micro holes / air passages with a micro hole depth of 5-10 mm are beneficial to improve the performance and quality of the ceramic products, the machining speed is fast, which is 1000% higher than that of the traditional CNC, and there is no tool wear, which is beneficial to popularization and application.

[0101] The above specific examples are further illustrations of the technical solutions and beneficial effects of the present application, and are not limitations of the embodiments. Any obvious replacement without departing from the concept of the present application is within the protection scope of the present application.

Claims

1. A method for machining micro-holes in a ceramic workpiece, characterized in that: The following steps are involved: Step 1: Processing preparation stage Before you begin, you need to prepare the ceramic sample workpiece to be processed and make sure its surface is clean and free of stains; Step 2: Positioning and marking Use computer-aided design software to draw the shape and position of the required microholes, and then use a laser system to mark them accurately; Step 3: Preprocessing Pre-treat the area of ​​the ceramic sample workpiece to be irradiated to remove contaminants on the surface; Step 4: Choose the right laser Select the appropriate type of laser according to processing requirements and adjust the laser power; Step 5: Fine processing Use pulse mode to reduce the heat-affected zone, continuously monitor the processing effect and make subtle adjustments to the parameters during the process; Step 6: Post-processing The workpiece that has completed laser fine processing will be further cleaned to remove residues to ensure the cleanliness of the workpiece surface; The second step of positioning marking is as follows: setting parameters according to the graphic data drawn by the CAD software; adjusting the laser power, focal length and other parameters to ensure accurate marking; starting the laser system and marking the ceramic sample according to the preset path and parameters, so that the ceramic sample shows micropores that match the designed shape; In step 3, the pretreatment method is a low-power scanning method or a method of adding a specific chemical agent to change the surface properties; In the step 4, the laser power is 5-10W, and the laser is a Nd:YAG ceramic laser with a wavelength of 850nm-1064nm; In the step 5, the short pulse width is 1-3 μs, the high pulse frequency is 5-10 kHz, the scanning speed is 80-100 mm / s, and the focal length of the focusing lens is 40-60 mm; After the post-processing of step 6, the step 7 is further included, namely, polishing or coating treatment. The polishing treatment is to polish the inner wall of the ceramic sample by mechanical polishing or chemical polishing to improve the surface finish of the workpiece; spray Teflon coating on the ceramic sample to improve the surface strength of the workpiece. The ceramic is aluminum oxide or silicon carbide ceramic.

2. A ceramic workpiece micro-hole processing method according to claim 1, characterized in that: In step 1, the ceramic sample workpiece is prepared as follows: Step 1, ingredients: accurately weigh various raw materials according to the required chemical composition; Step 2, mixing: mix the raw materials thoroughly; Step 3: Molding: Dry pressing, grouting, and other methods can be used, and the corresponding pressure, mold and other parameters can be set according to specific requirements; Step 4, drying: Drying under appropriate temperature and humidity conditions to remove moisture; Step 5, sintering: sintering is carried out in a high-temperature furnace, and appropriate process parameters such as sintering temperature, heating rate, and holding time are set to obtain the required ceramic properties and structure.

3. A ceramic workpiece micro-hole processing method according to claim 1, characterized in that: The low-power scanning method specifically refers to using a relatively low-power laser energy beam to scan the surface of the area to be irradiated.

4. A method for machining micro-holes in a ceramic workpiece according to claim 1, characterized in that: The step five of fine processing is specifically as follows: according to the material characteristics and processing accuracy requirements, the pulse frequency and pulse width parameters of the laser are set to minimize the heat affected zone. During the process, the surface quality and dimensional accuracy of the processing effects are closely observed, and the parameters are finely adjusted and optimized in a timely manner.

5. The method for machining micro-holes in a ceramic workpiece according to claim 1, wherein: The post-processing in step six is ​​specifically to use appropriate tools or methods to clean the debris, particles and other substances generated by laser processing remaining on the surface of the workpiece.

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