A method and apparatus for polishing the surface of reaction sintered silicon carbide

Abstract

The application provides a method and device for polishing the surface of reaction sintered silicon carbide, and the method comprises a polishing process, wherein the silicon carbide ceramic product to be polished is polished for 30-40 min at room temperature and under the condition of pH=2-3 by using abrasive particles and a polishing liquid; the polishing liquid is a Fenton auxiliary polishing liquid, the Fenton auxiliary polishing liquid is composed of an A solution and a B solution, the A solution is a 10-12wt% hydrogen peroxide solution, the B solution is composed of an acidic silica sol, diamond, ferrous chloride and water, and the viscosity of the B solution is 500-1000 cSt. By using the Fenton auxiliary polishing liquid and the special device, the reaction sintered silicon carbide ceramic product can be polished, and very good polishing effect can be obtained, the silicon carbide ceramic product has high smoothness and low surface roughness, and the mechanical strength and wear resistance of the surface of the silicon carbide ceramic product can be improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of semiconductors, and particularly relates to a method and device for polishing the surface of reaction sintered silicon carbide. BACKGROUND

[0002] Reaction sintered silicon carbide ceramic is a high-temperature, high-hardness and high-corrosion-resistant material with excellent performance, and is widely used in the fields of aerospace, semiconductors, chemical industry and the like. However, due to the high hardness and brittleness of silicon carbide ceramic, traditional polishing and grinding methods are prone to cause surface cracking and high roughness, affecting the mechanical properties and service life. The polishing liquid in the prior art is usually prepared in advance, and therefore has strict requirements on the viscosity, chemical stability and abrasive dispersion state of the polishing liquid, and also causes a series of problems in storage and transportation. Even so, the change in the state of the polishing liquid cannot be avoided, thereby affecting the polishing effect. Therefore, in the field of reaction sintered silicon carbide ceramic, a new polishing method and polishing liquid are urgently needed to ensure the polishing effect. SUMMARY

[0003] The application provides a method and device for polishing the surface of reaction sintered silicon carbide ceramic products, which can improve the surface quality and mechanical properties of the products.

[0004] The method for polishing the surface of reaction sintered silicon carbide ceramic products comprises a polishing process, in which the silicon carbide ceramic product to be polished is polished for 30-40 min at room temperature and under the condition of pH=2-3 by using abrasive particles and a polishing liquid.

[0005] The polishing liquid is a Fenton auxiliary polishing liquid, which is composed of an A solution and a B solution. The A solution is a 10-12 wt% hydrogen peroxide solution, and the B solution is composed of an acidic silica sol, diamond, ferrous chloride and water. The viscosity of the B solution is 500-1000 cSt. The viscosity of the B solution needs to be within a suitable range. If the viscosity is lower than the minimum value, the abrasive particles will excessively diffuse during the polishing process, causing uneven chemical reaction and affecting the surface quality. Moreover, the viscosity that is too low will easily cause stratification, and the abrasive particles will be deposited at the bottom, resulting in uneven composition of the polishing liquid, which is more difficult to control during dropping, and affects the polishing quality and stability. On the contrary, if the viscosity is higher than 1000 cSt, the B solution will be difficult to uniformly distributed on the surface of the material under the action of the machine, causing uneven material removal and uneven surface, increasing mechanical damage and causing fine scratches. In addition, the viscosity that is too high will also make it difficult for the abrasive particles to be uniformly dispersed, resulting in waste of raw materials.

[0006] The specific steps of the polishing process are: first, uniformly spray the to-be-polished area of the silicon carbide ceramic product with the B solution; then start polishing, and drop the A solution into the polishing disc during the polishing process. Unlike traditional polishing liquid and traditional polishing methods, the traditional polishing liquid is usually a solution prepared in advance, so there are strict requirements for the viscosity, chemical stability and abrasive dispersion state of the solution. The Fenton-assisted polishing liquid is prepared on site before polishing, and the hydrogen peroxide solution cannot be mixed with other components, so each component remains independent before the polishing liquid is prepared. Therefore, the Fenton-assisted polishing liquid has lower requirements for viscosity, chemical stability and abrasive dispersion state. During the polishing process, the A solution and the B solution meet to form a Fenton oxidation system, and the hydrogen peroxide and iron ions will generate strong oxidizing hydroxyl radicals (—OH), which can efficiently oxidize organic substances and impurities on the surface of silicon carbide.

[0007] Further, the speed of the polishing machine in the polishing process described in the application is n, with the unit of r / min; the polishing time is t, with the unit of min; and the dropping speed of the A solution into the polishing disc during the polishing process is w, with the unit of g / s;

[0008] And it satisfies: when 0 < t ≤ 20, w = 2e 0.5t , n = 40t;

[0009] When 20 < t ≤ T, w = 15 g / s, and n = 1000~1200 r / min, and the range of T is 30-40 min.

[0010] By preparing the A solution and the B solution on site before polishing respectively, and the hydrogen peroxide solution as the A solution is not mixed with the B solution, each component remains independent. With the help of the special device, the A solution and the B solution meet to form a Fenton oxidation system during the polishing process. Further, by matching a reasonable speed with an appropriate amount of polishing liquid, the Fenton reaction is continuously generated, while the cracking and damage of the surface of the silicon carbide ceramic can be effectively avoided.

[0011] Further, the mass fraction of the acidic silica sol in the B solution described in the application is 15~30%; the mass fraction of the diamond is 8~12%; and the mass fraction of the ferrous chloride is 1.5~3%.

[0012] Further, the method described in the application further includes a pretreatment process before the polishing process and a final treatment process after the polishing process; the pretreatment process includes coarse grinding, fine grinding, acid pickling detection and Fenton oxidation in sequence; and the final treatment process includes a cleaning and drying process and a detection process.

[0013] Further, the Fenton oxidation in the application is specifically: first, prepare a Fenton oxidation system liquid, the Fenton oxidation system liquid includes 7-10% of hydrogen peroxide by mass fraction and 0.1-0.2 mol / L of iron ions in concentration, then immerse the silicon carbide ceramic product after the acid pickling detection step in the Fenton oxidation system liquid, immerse for 40-60 min at a temperature of 20-25℃, and complete the Fenton oxidation process.

[0014] Further, the rough grinding treatment in the application is specifically: under the conditions of 500-1500 Pa pressure and 5000-10000 rpm rotation speed, grind the silicon carbide ceramic product by using a diamond grinding piece; to remove the unevenness and roughness on the surface of the silicon carbide ceramic.

[0015] Further, the fine grinding treatment in the application is specifically: regrind the silicon carbide ceramic product after the rough grinding treatment by using a fine grinding stone or grinding paper, and the pressure and rotation speed of the regrinding are 500-1500 Pa pressure and 5000-10000 rpm respectively; to further improve the surface flatness and smoothness.

[0016] Further, the acid pickling detection in the application is specifically: place the silicon carbide ceramic product after the fine grinding treatment in an appropriate amount of acid solution for acid pickling, the acid solution includes 40-50% of hydrofluoric acid solution by mass fraction, 30-40% of hydrochloric acid solution by mass fraction and deionized water, and the volume ratio of the hydrofluoric acid solution, the hydrochloric acid solution and the deionized water is 1:(2-4):(5-6); then detect the surface roughness, and the Ra is 25-50 μm. Since some impurities, dust or other pollutants will inevitably be assisted in the processing process, the acid pickling is to remove the impurities and small surface defects on the surface of the product, improve the ceramic quality and roughness, and also appropriately improve the adhesion of the ceramic surface, ensure that the abrasive grains can be more firmly attached to the surface in the subsequent process, and at the same time, the acid pickling can also remove the oxidation layer that may be generated in the sintering process or exposed to the air.

[0017] Further, the cleaning and drying process in the application is specifically: rinse 2-3 times with deionized water, and then dry at a temperature of 30-50℃ for 5-10 min; the detection process includes roughness detection, surface hardness detection and bending strength detection; the roughness Ra is 0.025-0.05 μm; the surface hardness is 2500-2600 HV by using a test force of 30 kg, maintaining for 20 seconds; and the bending strength is 550-580 MPa.

[0018] An apparatus for polishing the surface of reaction-bonded silicon carbide based on any one of the above-mentioned methods includes a polishing machine and a sample holder. The polishing machine includes a housing and a polishing disc located on the housing. The polishing disc is fixed to a rotating shaft at its bottom, and the rotating shaft is connected to the housing through a bushing.

[0019] Furthermore, the device described in this application also has a second support rod fixed on the housing, and the end of the second support rod is provided with a solution dispenser for holding solution A. The solution dispenser has its opening facing downward and is located above the polishing disc. A flow meter is also provided at the opening of the solution dispenser. The housing is also fixed with a solution tank for holding solution B. The solution tank has its opening facing upward, and a stirring mechanism is provided inside the solution tank. A nozzle is provided at the opening of the solution tank.

[0020] The sample rack includes a first support rod movably connected to the box body and a connecting rod fixedly connected to the first support rod. The end of the connecting rod away from the first support rod is provided with a clamping mechanism. The first support rod is an automatic telescopic rod.

[0021] The polishing machine also includes a polishing machine control system capable of controlling the rotation speed. The polishing machine control system includes a display screen and a timer, and a pressure sensor is also installed at the bottom of the polishing disc. The rotating shaft, pressure sensor, display screen, flow meter, timer, nozzle, stirring mechanism, and polishing machine control system are all electrically connected to the motor. Powered by the motor, the polishing machine control system first controls the stirring mechanism and nozzle to spray solution B onto the area to be polished on the reaction-sintered silicon carbide ceramic product before polishing. Then, it drives the timer to start, and simultaneously controls the polishing disc to rotate at a set speed, while the flow meter begins to drip solution A into the polishing disc, initiating the polishing process. During polishing, the polishing machine control system controls the height of the first support rod based on the polishing time displayed on the screen and the pressure value fed back by the pressure sensor at the bottom of the polishing disc. This controls the relative distance between the sample held by the clamping mechanism and the polishing disc, ensuring that appropriate pressure is maintained throughout the polishing process, ultimately achieving a good polishing effect.

[0022] Compared with the prior art, the present invention has the following beneficial technical effects:

[0023] The method and apparatus for polishing the surface of reaction-bonded silicon carbide described in this invention, using Fenton-assisted polishing fluid and the special device of this application, achieves excellent polishing results. It not only provides high gloss and low surface roughness but also improves the mechanical strength and wear resistance of the silicon carbide ceramic surface. Measurements show that the surface roughness Ra of the polished reaction-bonded silicon carbide ceramic product is 0.025~0.05 μm. The surface Vickers hardness is 2500~2600 HV30 / 20, and the flexural strength is 550~580 MPa; the hardness and flexural strength are increased by 8.4% and 7.9% respectively compared to before polishing. The Fenton-assisted polishing slurry used in this application is prepared on-site before polishing, consisting of solution A and solution B. The hydrogen peroxide solution in solution A is not mixed with solution B, and each component remains independent. During polishing, solution A and solution B meet to form a Fenton oxidation system. Hydrogen peroxide and iron ions generate highly oxidizing hydroxyl radicals (-OH), which can efficiently oxidize organic matter and impurities on the silicon carbide surface. Furthermore, the method and apparatus described in this application, through a reasonable rotation speed and an appropriate amount of polishing slurry, ensure the continuous occurrence of the Fenton reaction while effectively avoiding cracking and breakage of the silicon carbide ceramic surface. The high-quality silicon carbide ceramic products obtained by the method described in this application can be widely used in aerospace, semiconductor, and other fields. Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating the method described in Embodiment 1 of the present invention;

[0025] Figure 2 This is a schematic diagram of the structure of the reaction-sintered silicon carbide surface polishing device described in this invention;

[0026] The components include: 1. Polishing machine, 2. Sample holder, 3. Second support rod, 4. Solution dispenser, 5. Flow meter, 6. Solution tank, 7. Stirring mechanism, and 8. Nozzle.

[0027] 101. Box body; 102. Polishing disc; 201. First support rod; 202. Connecting rod; 203. Clamping mechanism. Detailed Implementation Specific Implementation Method 1

[0029] A method for polishing the surface of reaction-bonded silicon carbide, the method comprising a polishing process, wherein the silicon carbide ceramic product to be polished is polished for 30-40 minutes at room temperature and pH=2~3 by using abrasive particles and polishing liquid;

[0030] The polishing slurry is a Fenton-assisted polishing slurry, which is composed of solution A and solution B. Solution A is a 10-12 wt% hydrogen peroxide solution, and solution B is composed of acidic silica sol, diamond, ferrous chloride and water. The viscosity of solution B is 500-1000 cSt.

[0031] The specific steps of the polishing process are as follows: First, the area of ​​the silicon carbide ceramic product to be polished is uniformly sprayed with the solution B; then polishing begins, and solution A is added to the polishing pad during the polishing process.

[0032] The polishing machine's rotation speed during the polishing process is n, in r / min; the polishing time is t, in seconds (min); and the dripping rate of solution A added to the polishing disc during the polishing process is w, in g / s.

[0033] And it satisfies: when 0 < t ≤ 20, w = 2e 0.5t n=40t;

[0034] When 20 < t ≤ T, w = 15 g / s and n = 1000~1200 r / min are satisfied, and the range of T is 30-40 min.

[0035] The mass fraction of acidic silica sol in solution B is 15-30%; the mass fraction of diamond is 8-12%; and the mass fraction of ferrous chloride is 1.5-3%. Specific Implementation Method Two

[0037] An apparatus based on the reaction sintering silicon carbide surface polishing method described in Embodiment 1 includes a polishing machine 1 and a sample holder 2. The polishing machine 1 includes a housing 101 and a polishing disc 102 located on the housing 101. The polishing disc 102 is fixed to the bottom by a rotating shaft, and the rotating shaft is connected to the housing 101 through a bushing.

[0038] A second support rod 3 is also fixed on the housing 101. The end of the second support rod 3 is provided with a solution dispenser 4 for holding solution A. The solution dispenser 4 has its opening facing downward and is located above the polishing disc 102. A flow meter 5 is also provided at the opening of the solution dispenser 4. A solution tank 6 for holding solution B is also fixed on the housing 101. The solution tank 6 has its opening facing upward. A stirring mechanism 7 is provided inside the solution tank 6. A nozzle 8 is provided at the opening of the solution tank 6. Example 1

[0039] A method for polishing the surface of reaction-sintered silicon carbide, such as Figure 1As shown, the method includes a pretreatment process before polishing, a polishing process, and a final treatment process after polishing. The pretreatment process sequentially includes coarse grinding, fine grinding, acid washing and testing, and Fenton oxidation. The polishing process involves polishing the silicon carbide ceramic product to be polished using abrasive particles and polishing fluid at room temperature and pH 2-3 for 30-40 minutes. The final treatment process includes a cleaning and drying process and a testing process.

[0040] In this embodiment 1, the rough grinding process specifically involves grinding the silicon carbide ceramic product using a diamond grinding disc under a pressure of 1000 Pa and a rotation speed of 5000~10000 rpm.

[0041] The fine grinding process specifically involves using fine grinding stones or abrasive paper to grind the coarsely ground silicon carbide ceramic product again. The pressure and rotation speed of the second grinding are 1200 Pa and 5000~10000 rpm, respectively.

[0042] In this embodiment 1, the pickling test specifically involves: placing the silicon carbide ceramic product that has undergone fine grinding into an appropriate amount of acidic solution for pickling. The acidic solution includes a 47% hydrofluoric acid solution, a 38% hydrochloric acid solution, and deionized water, with a volume ratio of 1:3:6. Then, the surface roughness is tested, and the measured Ra is 30 μm.

[0043] In this embodiment 1, the Fenton oxidation specifically involves: first, preparing a Fenton oxidation system solution, which includes 7.7% hydrogen peroxide by mass and 0.1 mol / L iron ions; then immersing the silicon carbide ceramic product that has completed the pickling and testing steps in the Fenton oxidation system solution at 25°C for 60 minutes to complete the Fenton oxidation process.

[0044] The polishing fluid used in the polishing process is Fenton-assisted polishing fluid, which consists of solution A and solution B. Solution A is a 10wt% hydrogen peroxide solution, and solution B is composed of acidic silica sol, diamond, ferrous chloride and water. The viscosity of solution B is 800 cSt.

[0045] The specific steps of the polishing process are as follows: First, the area to be polished of the silicon carbide ceramic product is uniformly sprayed with the B solution; then polishing begins, and during the polishing process, the A solution is added dropwise to the polishing pad. The mass fraction of acidic silica sol in the B solution is 15-30%; the mass fraction of diamond is 8-12%; and the mass fraction of ferrous chloride is 1.5-3%.

[0046] The polishing machine's rotation speed during the polishing process is n, in r / min; the polishing time is t, in seconds (min); and the dripping rate of solution A added to the polishing disc during the polishing process is w, in g / s.

[0047] And it satisfies: when 0 < t ≤ 20, w = 2e 0.5t n=40t;

[0048] When 20 < t ≤ T, w = 15 g / s and n = 1000~1200 r / min are satisfied, and the range of T is 30-40 min.

[0049] In this embodiment 1, the cleaning and drying process specifically involves rinsing with deionized water 2-3 times, and then drying at 40°C for 10 minutes; the testing process includes roughness testing, surface hardness testing, and bending strength testing; the roughness Ra was measured to be 0.03 μm; the surface hardness was determined by applying a test force of 30 kgf for 20 seconds, resulting in a hardness value of 2512 HV; and the bending strength was 576 MPa. Example 2

[0050] An apparatus for polishing the surface of reaction-sintered silicon carbide based on the method of Example 1, such as Figure 2 As shown, it includes a polishing machine 1 and a sample holder 2. The polishing machine 1 includes a housing 101 and a polishing disc 102 located on the housing 101. The polishing disc 102 is fixed to the bottom by a rotating shaft, and the rotating shaft is connected to the housing 101 by a bushing.

[0051] A second support rod 3 is also fixed on the housing 101. The end of the second support rod 3 is provided with a solution dispenser 4 for holding solution A. The solution dispenser 4 has its opening facing downward and is located above the polishing disc 102. A flow meter 5 is also provided at the opening of the solution dispenser 4. A solution tank 6 for holding solution B is also fixed on the housing 101. The solution tank 6 has its opening facing upward. A stirring mechanism 7 is provided inside the solution tank 6. A nozzle 8 is provided at the opening of the solution tank 6.

[0052] In this embodiment 2, the sample holder 2 includes a first support rod 201 movably connected to the housing 101 and a connecting rod 202 fixedly connected to the first support rod 201. A clamping mechanism 203 is provided at the end of the connecting rod 202 away from the first support rod 201. The first support rod 201 is an automatic telescopic rod. In this embodiment 2, the first support rod 201 is a miniature electric telescopic rod, specifically the electric push rod miniature thumb push rod with high thrust 12 / 24V DC LEGO robot linear telescopic rod from Zhejiang Haorang Technology Co., Ltd.

[0053] The polishing machine 1 also includes a polishing machine control system capable of controlling the rotation speed. The polishing machine control system includes a display screen and a timer. A pressure sensor is also provided at the bottom of the polishing disc 102. The rotating shaft, pressure sensor, display screen, flow controller 5, timer, nozzle 8, stirring mechanism 7, and polishing machine control system are all electrically connected to the motor. In this embodiment 2, the flow controller 5 is implemented using a P-series micro flow meter from Shanghai Jishen Instrument Co., Ltd.

[0054] The polishing process specifically includes the following steps:

[0055] First, the reactive sintered silicon carbide ceramic product to be polished is clamped onto the clamping mechanism 203. Then, the first support rod 201 is rotated to position the ceramic product above the solution tank 6. Next, the stirring mechanism 7 is controlled by the polishing machine control system to stir for 10-20 seconds, after which solution B is sprayed onto the polishing area of ​​the ceramic product through the nozzle 8. After spraying, the first support rod 201 is rotated to a suitable position.

[0056] The polishing machine control system controls the height of the first support rod 201 to ensure the pressure displayed on the screen is within the range of 500~1500 Pa. The timer and polishing disc 102 are then activated. The polishing machine control system controls the polishing disc to rotate at a set speed, and the flow meter 5 begins adding solution A to the polishing disc 102 at a specific dripping rate, thus initiating the polishing process. During polishing, the polishing machine control system controls the height of the first support rod 201 based on the polishing time displayed on the screen and the pressure value fed back from the pressure sensor at the bottom of the polishing disc 102. This controls the relative distance between the sample held by the clamping mechanism 203 and the polishing disc 102, ensuring that appropriate pressure is maintained throughout the polishing process, ultimately achieving a good polishing effect.

[0057] This invention has been described through the specific embodiments described above. Those skilled in the art should understand that various modifications and equivalent substitutions can be made to this invention without departing from its scope. Parts not described in detail in this specification are well-known to those skilled in the art. Furthermore, various modifications can be made to this invention for specific situations or circumstances without departing from its scope. Therefore, this invention is not limited to the specific embodiments disclosed, but should include all embodiments falling within the scope of the claims.

Claims

1. A method for polishing the surface of reaction-sintered silicon carbide, characterized in that, The method includes a polishing process, in which the silicon carbide ceramic product to be polished is polished for 30-40 minutes at room temperature and pH=2~3 using an abrasive and polishing liquid method. The polishing slurry is a Fenton-assisted polishing slurry, which is composed of solution A and solution B. Solution A is a 10-12 wt% hydrogen peroxide solution, and solution B is composed of acidic silica sol, diamond, ferrous chloride and water. The viscosity of solution B is 500-1000 cSt. The specific steps of the polishing process are as follows: First, the area of ​​the silicon carbide ceramic product to be polished is uniformly sprayed with the solution B; then polishing begins, and solution A is added to the polishing pad during the polishing process.

2. The method according to claim 1, characterized in that, The mass fraction of acidic silica sol in solution B is 15-30%; the mass fraction of diamond is 8-12%; and the mass fraction of ferrous chloride is 1.5-3%.

3. The method according to claim 2, characterized in that, The method also includes a pretreatment process before the polishing process and a final treatment process after the polishing process; The pretreatment process includes coarse grinding, fine grinding, acid washing and detection, and Fenton oxidation in sequence; the final treatment process includes cleaning and drying and detection.

4. The method according to claim 3, characterized in that, The Fenton oxidation process specifically involves: first, preparing a Fenton oxidation system solution, which includes 7-10% hydrogen peroxide by mass and 0.1-0.2 mol / L iron ions; then immersing the silicon carbide ceramic product that has completed the acid pickling and testing steps in the Fenton oxidation system solution at a temperature of 20-25°C for 40-60 minutes to complete the Fenton oxidation process.

5. The method according to claim 4, characterized in that, The rough grinding process specifically involves grinding silicon carbide ceramic products using diamond grinding discs under a pressure of 500~1500 Pa and a rotation speed of 5000~10000 rpm. The fine grinding process specifically involves using fine grinding stones or abrasive paper to grind the coarsely ground silicon carbide ceramic product again, with a pressure of 500~1500 Pa and a rotation speed of 5000~10000 rpm for the second grinding. The pickling test specifically involves placing the silicon carbide ceramic product that has undergone fine grinding into an appropriate amount of acidic solution for pickling. The acidic solution includes a hydrofluoric acid solution with a mass fraction of 40-50%, a hydrochloric acid solution with a mass fraction of 30-40%, and deionized water. The volume ratio of the hydrofluoric acid solution, hydrochloric acid solution, and deionized water is 1:(2-4):(5-6). Then, the surface roughness is tested, and the Ra is measured to be 25-50 μm.

6. The method according to claim 5, characterized in that, The cleaning and drying process specifically involves rinsing with deionized water 2-3 times, followed by drying at 30-50°C for 5-10 minutes. The testing process includes roughness testing, surface hardness testing, and bending strength testing. The roughness Ra is measured to be 0.025-0.05 μm. The surface hardness is determined by applying a test force of 30 kgf for 20 seconds, resulting in a hardness value of 2500-2600 HV. The bending strength is measured to be 550-580 MPa.

7. An apparatus for polishing the surface of reaction-sintered silicon carbide according to any one of claims 1 to 6, characterized in that, The device includes a polishing machine (1) and a sample holder (2). The polishing machine (1) includes a housing (101) and a polishing disc (102) located on the housing (101). The polishing disc (102) is fixed to the bottom by a rotating shaft, and the rotating shaft is connected to the housing (101) by a bushing. A second support rod (3) is also fixed on the box (101). The end of the second support rod (3) is provided with a solution dispenser (4) for holding solution A. The solution dispenser (4) has its opening facing downward and is located above the polishing disc (102). A flow meter (5) is also provided at the opening of the solution dispenser (4). A solution tank (6) for holding solution B is also fixed on the box (101). The solution tank (6) has its opening facing upward. A stirring mechanism (7) is provided inside the solution tank (6). A nozzle (8) is provided at the opening of the solution tank (6).

8. The apparatus according to claim 7, characterized in that, The sample rack (2) includes a first support rod (201) movably connected to the box body (101) and a connecting rod (202) fixedly connected to the first support rod (201). The end of the connecting rod (202) away from the first support rod (201) is provided with a clamping mechanism (203). The first support rod (201) is an automatic telescopic rod.

9. The device according to claim 8, the polishing machine (1) further includes a polishing machine control system capable of controlling the rotation speed, the polishing machine control system includes a display screen and a timer, and a pressure sensor is also provided at the bottom of the polishing disc (102); the rotating shaft, pressure sensor, display screen, flow meter (5), timer, nozzle (8), stirring mechanism (7) and polishing machine control system are all electrically connected to the motor.

Images