Ultrasonic vibration assisted hole grinding machining method for carbon fiber / bismaleimide resin composite material

Abstract

The invention discloses an ultrasonic vibration assisted hole grinding machining method for a carbon fiber / bismaleimide resin composite material, and relates to the technical field of composite material machining. The method comprises the following steps: cutting the carbon fiber / bismaleimide resin-based composite material into blocks, and clamping a sample on a numerical control machining center; an electroplated diamond abrasive particle hollow grinding head tool is selected, a laser displacement sensor is used for detecting the vibration displacement of the end of the tool, and the overhanging amount of the tool is adjusted to reach the maximum amplitude value of the tool; and the installed carbon fiber / bismaleimide resin-based composite material is subjected to ultrasonic vibration assisted double-helix hole grinding. According to the invention, the high-efficiency and high-quality drilling processing of the carbon fiber / bismaleimide resin composite material is realized by inhibiting the layering of the hole outlet and the formation of burrs and reducing the tearing of the outlet and the roughness of the hole wall.

Description

Technical Field

[0001] The invention relates to the technical field of composite material processing, and in particular to an ultrasonic vibration assisted hole grinding processing method for a carbon fiber / bismaleimide resin composite material. Background Art

[0002] Carbon fiber / bismaleimide resin-based composite material is an advanced carbon fiber reinforced resin composite material, which not only has the advantages of high strength, high stiffness, low density, but also has the properties of fatigue resistance, high temperature resistance, moisture resistance, etc. Due to its excellent performance, carbon fiber / bismaleimide resin composite materials are often used to prepare main load-bearing structures that serve at higher temperatures, and have broad application prospects in aerospace and other fields. Among them, the main connection methods are bolt connection and riveting, so the processing of connecting holes of carbon fiber / bismaleimide resin composite materials is an indispensable process. However, due to the material properties of carbon fiber / bismaleimide resin composite materials such as inhomogeneity, anisotropy, high hardness, and poor interlayer toughness, it becomes a typical difficult-to-process material. In traditional mechanical processing, especially drilling processing, defects such as delamination, tearing, burrs and scratches on the surface of the hole wall are very likely to occur, and it is impossible to achieve efficient and high-quality processing of carbon fiber / bismaleimide resin composite materials.

[0003] The existing technology has studied the formation mechanism, classification and evaluation of the damage of drilling carbon fiber reinforced resin-based composite materials, and pointed out that improving the tool and developing advanced hole making technology can inhibit CFRP drilling damage. At the same time, the existing technology summarizes the influence of process parameters (tool characteristics and geometric parameters, ultrasonic vibration frequency and amplitude, feed speed, spindle speed, cutting depth) on processing characteristics (delamination, torque, cutting force) during the drilling process of carbon fiber reinforced resin-based composite materials, and ultrasonic vibration assisted processing can effectively reduce processing damage. Those skilled in the art have found that due to the high brittleness and low fracture toughness of BMI resin, when drilling with a diamond drill, there will be exit delamination, tearing around the hole and scratches on the hole wall surface, and the core will block the tool. Through the above research, it was found that carbon fiber / BMI resin composite materials have problems such as delamination, tearing, burrs and scratches on the hole wall during traditional drilling, and it is impossible to achieve efficient and high-quality hole making in carbon fiber / BMI resin composite materials. Summary of the invention

[0004] In view of the deficiencies in the above-mentioned background technology, the present invention mainly solves the problems of outlet delamination, tearing, burrs and large hole wall roughness in the conventional drilling process of carbon fiber / bismaleimide resin-based composite materials in the prior art. The present invention provides a method for ultrasonic vibration-assisted hole grinding of carbon fiber / bismaleimide resin composite materials. The method suppresses the formation of hole outlet delamination and burrs, reduces outlet tearing and hole wall roughness, and realizes efficient and high-quality hole making of carbon fiber / bismaleimide resin composite materials.

[0005] The object of the present invention is to provide a method for ultrasonic vibration-assisted hole grinding of a carbon fiber / bismaleimide resin composite material, which is characterized by comprising the following steps: The carbon fiber / bismaleimide resin-based composite material is cut into blocks, the surface is treated to be smooth, and the edges are polished to obtain a carbon fiber / bismaleimide resin-based composite material processing sample, and then the sample is clamped on a CNC machining center; Select an electroplated diamond abrasive hollow grinding head tool and install it on an ultrasonic tool holder with a vibration frequency of 30~40kHz; Connect the ultrasonic generator, ultrasonic tool holder and CNC machining center; Turn on the power supply and working switch of the ultrasonic generator, adjust the current value, and adjust the frequency of the ultrasonic generator to the frequency parameters required for processing, and dip water on the end of the tool with a brush. It can be seen that the water vibrates and atomizes, indicating that the vibration effect is in a resonant state; Use a laser displacement sensor to detect the vibration displacement of the tool end and adjust the tool overhang to achieve the maximum tool amplitude; The installed carbon fiber / bismaleimide resin-based composite material was subjected to ultrasonic vibration-assisted double-helix hole grinding, wherein the spindle speed was 3000-7000 r / min, the feed speed was 60-140 mm / min, the pitch was 0.1-0.3 mm / r, and the tool eccentricity was 1 mm; the hole grinding was completed.

[0006] Preferably, in the process of ultrasonic vibration-assisted double-helix hole grinding of carbon fiber / bismaleimide resin-based composite materials, a dry processing method without adding coolant is adopted.

[0007] Preferably, the power of the ultrasonic vibration device is turned on during the ultrasonic vibration-assisted double-helix hole grinding process.

[0008] Preferably, the tool parameters are: tool outer diameter 4 mm, tool inner diameter 2.6 mm, tool rod total length 50 mm, and sand-plated length 5 mm.

[0009] Preferably, when the tool overhang is adjusted to reach the maximum tool amplitude, the amplitude is 11 μm when the overhang is 26 mm.

[0010] Preferably, an Alicona Infinite Focus G4 fully automatic scanner is used to detect the hole entrance and exit morphologies after ultrasonic vibration-assisted spiral grinding of the carbon fiber / bismaleimide resin composite material, the Image software is used to calculate the outlet tearing area, and the Alicona Infinite Focus G4 fully automatic scanner is used to detect the hole wall morphology and surface roughness.

[0011] Preferably, a non-dominated sorting genetic algorithm is used to perform multi-objective optimization of process parameters for three index parameters: hole wall roughness, outlet tear area, and material removal rate. The outlet tear area is less than 0.5 mm. 2 , the hole wall roughness Sa value is less than 2.1 μm, and the single hole processing time is shortened to 1.2-1.8 seconds.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a method for ultrasonic vibration-assisted hole grinding of carbon fiber / bismaleimide resin composite materials. The method uses a hollow grinding head with a diameter of 4 mm and an eccentricity of 1 mm. Diamond abrasive grains on the inner and outer walls of the tool are used for inner and outer double spiral grinding. By optimizing process parameters, in the hole making process of the carbon fiber / bismaleimide resin-based composite material, there is no outlet delamination, and extremely small tearing and hole wall roughness are obtained. With the processing method of the present invention, high-quality holes can be obtained by ultrasonic vibration-assisted spiral hole grinding at the same processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The electroplated diamond hollow grinding head used in the embodiment; Figure 2 Schematic diagram of ultrasonic vibration-assisted double-helix hole grinding process used in the embodiment; Figure 3 The inlet and outlet morphologies of the holes processed by the method of the present invention in the embodiment; Figure 4 The morphology of the hole wall processed by the method of the present invention in the embodiment; Figure 5 Drilling damage of the twist drill used in the comparative example. DETAILED DESCRIPTION

[0014] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below in conjunction with specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0015] The purpose of the present invention is to solve the problems of outlet delamination, tearing, burrs and large hole wall roughness existing in traditional drilling processing of carbon fiber / bismaleimide resin-based composite materials, and to provide an ultrasonic vibration assisted double-helix hole grinding processing method for carbon fiber / bismaleimide resin-based composite materials to inhibit the formation of hole outlet delamination and burrs, reduce outlet tearing and hole wall roughness, and realize efficient and high-quality hole making processing of carbon fiber / bismaleimide resin composite materials.

[0016] In order to achieve the above object, the present invention provides a method for ultrasonic vibration-assisted hole grinding of a carbon fiber / bismaleimide resin composite material, comprising the following steps: The carbon fiber / bismaleimide resin-based composite material is cut into blocks, the surface is treated to be smooth, and the edges are polished to obtain a carbon fiber / bismaleimide resin-based composite material processing sample, and then the sample is clamped on a CNC machining center; Select an electroplated diamond abrasive hollow grinding head tool and install it on an ultrasonic tool holder with a vibration frequency of 30~40kHz; Connect the ultrasonic generator, ultrasonic tool holder and CNC machining center; Turn on the power supply and working switch of the ultrasonic generator, adjust the current value, and adjust the frequency of the ultrasonic generator to the frequency parameters required for processing, and dip water on the end of the tool with a brush. It can be seen that the water vibrates and atomizes, indicating that the vibration effect is in a resonant state; Use a laser displacement sensor to detect the vibration displacement of the tool end and adjust the tool overhang to achieve the maximum tool amplitude; The installed carbon fiber / bismaleimide resin-based composite material was subjected to ultrasonic vibration-assisted double-helix hole grinding, wherein the spindle speed was 3000-7000 r / min, the feed speed was 60-140 mm / min, the pitch was 0.1-0.3 mm / r, and the tool eccentricity was 1 mm; the hole grinding was completed.

[0017] Among them, in the ultrasonic vibration-assisted double-helix hole grinding process of carbon fiber / bismaleimide resin-based composite materials, a dry processing method without adding coolant is adopted.

[0018] During the ultrasonic vibration-assisted double-helix grinding process, the power of the ultrasonic vibration device is turned on.

[0019] The tool parameters are as follows: tool outer diameter 4 mm, tool inner diameter 2.6 mm, tool bar total length 50 mm, and sand plating length 5 mm.

[0020] When the tool overhang is adjusted to the maximum tool amplitude, the amplitude is 11 μm when the overhang is 26 mm.

[0021] Alicona Infinite Focus G4 fully automatic scanner was used to detect the entrance and exit morphologies of the holes after ultrasonic vibration assisted spiral grinding of carbon fiber / bismaleimide resin composite materials. Image software was used to calculate the area of ​​the outlet tearing zone. Alicona Infinite Focus G4 fully automatic scanner was used to detect the hole wall morphology and surface roughness.

[0022] The non-dominated sorting genetic algorithm was used to perform multi-objective optimization of process parameters for three index parameters: hole wall roughness, outlet tear area, and material removal rate. The outlet tear area was less than 0.5 mm. 2, the hole wall roughness Sa value is less than 2.1 μm, and the single hole processing time is shortened to 1.2-1.8 seconds.

[0023] In one embodiment, a method for ultrasonic vibration-assisted hole grinding of a carbon fiber / bismaleimide resin composite material is provided, comprising the following steps: Step 1: Prepare carbon fiber / bismaleimide resin composite material specimens. Use high-pressure water to cut a unidirectionally laminated carbon fiber / bismaleimide resin-based composite material with a grade of ZT7H / QY9611 and a thickness of 2 mm into a block of 200 mm × 90 mm, make its surface smooth, and polish the edges with sandpaper to obtain a carbon fiber / bismaleimide resin-based composite material processing specimen, which is then clamped in the ZMC-T6 CNC machining center.

[0024] Step 2: Connect the ultrasonic vibration machining system to the machining center.

[0025] Step 3: Select the electroplated diamond abrasive hollow grinding head tool and install it on the ultrasonic tool holder. The selected tools are as follows Figure 1 As shown, the tool parameters are outer diameter 4 mm, inner diameter 2.6 mm, total length 50 mm, sand plating length 5 mm, abrasive grain size 200 mesh, and substrate 45 steel.

[0026] Step 4: Turn on the power supply and working switch of the ultrasonic generator, adjust the current value, observe the frequency value on the ultrasonic generator screen, make it within the frequency parameters required for processing, the ultrasonic frequency is 38.488 kHz, and dip water on the end of the tool with a brush. You can see the water vibrates and atomizes, indicating that the vibration effect is in a resonant state.

[0027] Step 5: Use LK-H020 laser displacement sensor to detect and adjust the tool overhang multiple times to reach the maximum amplitude. At this time, the overhang is 26 mm and the amplitude A=11 μm.

[0028] Step 6: In the ultrasonic vibration-assisted spiral grinding process of carbon fiber / bismaleimide resin-based composite materials, a dry processing method without adding coolant is adopted.

[0029] Step 7: Perform ultrasonic vibration assisted double spiral grinding process experiment on the installed carbon fiber / bismaleimide resin-based composite material. Ultrasonic vibration assisted spiral grinding: spindle speed 3000~7000 r / min, feed speed 60~140 mm / min, pitch 0.1~0.3 mm / r, eccentricity 1 mm. Figure 2 As shown, the power of the ultrasonic vibration device is turned on during the ultrasonic vibration-assisted spiral hole grinding process.

[0030] Step 8: Hole quality inspection. After the specimen is cleaned with anhydrous ethanol in an ultrasonic cleaner, the Alicona Infinite Focus G4 fully automatic scanner is used to inspect the hole entrance and exit morphologies after ultrasonic vibration-assisted spiral grinding of carbon fiber / bismaleimide resin composite materials. Figure 3 As shown in the figure, there is no tearing, burr, crack or other damage at the hole entrance and exit, and the processed hole diameter is within the range of 6±0.05 mm. The tear area of ​​the exit is calculated using Image software, and the tear area is less than 1.5 mm 2 After the hole was cut open with a diamond slicer, the Alicona InfiniteFocus G4 fully automatic scanner was used to detect the hole wall morphology and surface roughness. Figure 4 As shown in the figure, no delamination or obvious scratches were found on the hole wall, and the hole wall roughness Sa value was less than 3 μm.

[0031] Step 9: Optimization of ultrasonic vibration-assisted spiral grinding process parameters. The non-dominated sorting genetic algorithm is used to perform multi-objective optimization of process parameters for three index parameters: hole wall roughness, outlet tear area, and material removal rate. The outlet tear area is less than 0.5 mm. 2 , the hole wall roughness Sa value is less than 2.1 μm, and the single hole processing time is shortened to 1.2-1.8 seconds.

[0032] It should be noted that the experimental methods used in the present invention are all conventional methods unless otherwise specified; the reagents and materials used are all commercially available unless otherwise specified.

[0033] Example 1 Step 1: Prepare carbon fiber / bismaleimide resin composite material specimens. Use high-pressure water to cut a unidirectionally laminated carbon fiber / bismaleimide resin-based composite material with a grade of ZT7H / QY9611 and a thickness of 2 mm into a block of 200 mm × 90 mm, make its surface smooth, and polish the edges with sandpaper to obtain a carbon fiber / bismaleimide resin-based composite material processing specimen, which is then clamped in the ZMC-T6 CNC machining center.

[0034] Step 2: Connect the ultrasonic vibration machining system to the machining center.

[0035] Step 3: Select the electroplated diamond abrasive hollow grinding head tool and install it on the ultrasonic tool holder. The selected tools are as follows Figure 1 As shown, the tool parameters are outer diameter 4 mm, inner diameter 2.6 mm, total length 50 mm, sand plating length 5 mm, abrasive grain size 200 mesh, and substrate 45 steel.

[0036] Step 4: Turn on the power supply and working switch of the ultrasonic generator, adjust the current value, observe the frequency value on the ultrasonic generator screen, make it within the frequency parameters required for processing, the ultrasonic frequency is 38.488 kHz, and dip water on the end of the tool with a brush. You can see the water vibrates and atomizes, indicating that the vibration effect is in a resonant state.

[0037] Step 5: Use LK-H020 laser displacement sensor to detect and adjust the tool overhang multiple times to reach the maximum amplitude. At this time, the overhang is 26 mm and the amplitude A=11 μm.

[0038] Step 6: In the ultrasonic vibration-assisted spiral grinding process of carbon fiber / bismaleimide resin-based composite materials, a dry processing method without adding coolant is adopted.

[0039] Step 7: Perform ultrasonic vibration assisted spiral hole grinding process experiment on the installed carbon fiber / bismaleimide resin-based composite material. Ultrasonic vibration assisted spiral hole grinding was adopted: spindle speed 6254 r / min, feed speed 65 mm / min, pitch 0.15 mm / r, eccentricity 1 mm. The power of the ultrasonic vibration equipment was turned on during the ultrasonic vibration assisted spiral hole grinding process.

[0040] Step 8: Hole quality inspection. After the specimen was cleaned with anhydrous ethanol in an ultrasonic cleaner, the Alicona Infinite Focus G4 fully automatic scanner was used to inspect the entrance and exit morphology of the processed hole. There were no burrs, cracks or other damage at the entrance and exit of the hole, and the processed hole diameter was 5.968 mm. The tear area of ​​the exit was calculated using Image software, and the tear area was 0.168 mm. 2 After the hole was cut open with a diamond slicer, the AliconaInfinite Focus G4 fully automatic scanner was used to detect the hole wall morphology and surface roughness. No delamination or obvious scratches were found on the hole wall, and the hole wall roughness Sa value was 2.023 μm.

[0041] Example 2 Steps 1 to 6 are the same as those in Example 1; Step 7: Perform ultrasonic vibration assisted spiral hole grinding process experiment on the installed carbon fiber / bismaleimide resin-based composite material. Ultrasonic vibration assisted spiral hole grinding was adopted: spindle speed 5648 r / min, feed speed 97 mm / min, pitch 0.24 mm / r, eccentricity 1 mm. The power of the ultrasonic vibration equipment was turned on during the ultrasonic vibration assisted spiral hole grinding process.

[0042] Step 8: Hole quality inspection. After the specimen was cleaned with anhydrous ethanol in an ultrasonic cleaner, the Alicona Infinite Focus G4 fully automatic scanner was used to inspect the entrance and exit morphology of the processed hole. There were no burrs, cracks or other damage at the entrance and exit of the hole, and the processed hole diameter was 5.982 mm. The tear area of ​​the exit was calculated using Image software, and the tear area was 0.455 mm. 2 After the hole was cut open with a diamond slicer, the Alicona Infinite Focus G4 fully automatic scanner was used to detect the hole wall morphology and surface roughness. No delamination or obvious scratches were found on the hole wall, and the hole wall roughness Sa value was 2.011 μm.

[0043] Example 3 Steps 1 to 6 are the same as those in Example 1; Step 7: Perform ultrasonic vibration assisted spiral hole grinding process experiment on the installed carbon fiber / bismaleimide resin-based composite material. Ultrasonic vibration assisted spiral hole grinding was adopted: spindle speed 6564 r / min, feed speed 80 mm / min, pitch 0.12 mm / r, eccentricity 1 mm. The power of the ultrasonic vibration equipment was turned on during the ultrasonic vibration assisted spiral hole grinding process.

[0044] Step 8: Hole quality inspection. After the specimen was cleaned with anhydrous ethanol in an ultrasonic cleaner, the Alicona Infinite Focus G4 fully automatic scanner was used to inspect the entrance and exit morphology of the processed hole. There were no burrs, cracks or other damage at the entrance and exit of the hole, and the processed hole diameter was 5.993 mm. The tear area of ​​the exit was calculated using Image software, and the tear area was 0.285 mm. 2 After the hole was cut open with a diamond slicer, the Alicona Infinite Focus G4 fully automatic scanner was used to detect the hole wall morphology and surface roughness. No delamination or obvious scratches were found on the hole wall, and the hole wall roughness Sa value was 1.621 μm.

[0045] Example 4 Steps 1 to 6 are the same as those in Example 1; Step 7: Perform ultrasonic vibration assisted spiral hole grinding process experiment on the installed carbon fiber / bismaleimide resin-based composite material. Ultrasonic vibration assisted spiral hole grinding was adopted: spindle speed 4802 r / min, feed speed 83 mm / min, pitch 0.1mm / r, eccentricity 1 mm. The power of the ultrasonic vibration equipment was turned on during the ultrasonic vibration assisted spiral hole grinding process.

[0046] Step 8: Hole quality inspection. After the specimen was cleaned with anhydrous ethanol in an ultrasonic cleaner, the Alicona Infinite Focus G4 fully automatic scanner was used to inspect the entrance and exit morphology of the processed hole. There were no burrs, cracks or other damage at the entrance and exit of the hole, and the processed hole diameter was 5.978 mm. The tear area of ​​the exit was calculated using Image software, and the tear area was 0.401 mm. 2 After the hole was cut open with a diamond slicer, the Alicona Infinite Focus G4 fully automatic scanner was used to detect the hole wall morphology and surface roughness. No delamination or obvious scratches were found on the hole wall, and the hole wall roughness Sa value was 1.075 μm.

[0047] Example 5 Steps 1 to 6 are the same as those in Example 1; Step 7: Perform ultrasonic vibration assisted spiral hole grinding process experiment on the installed carbon fiber / bismaleimide resin-based composite material. Ultrasonic vibration assisted spiral hole grinding was adopted: spindle speed 3844 r / min, feed speed 95 mm / min, pitch 0.19 mm / r, eccentricity 1 mm. The power of the ultrasonic vibration equipment was turned on during the ultrasonic vibration assisted spiral hole grinding process.

[0048] Step 8: Hole quality inspection. After the specimen was cleaned with anhydrous ethanol in an ultrasonic cleaner, the Alicona Infinite Focus G4 fully automatic scanner was used to inspect the entrance and exit morphology of the processed hole. There were no burrs, cracks or other damage at the entrance and exit of the hole, and the processed hole diameter was 5.969 mm. The tear area of ​​the exit was calculated using Image software, and the tear area was 0.481 mm. 2 After the hole was cut open with a diamond slicer, the Alicona Infinite Focus G4 fully automatic scanner was used to detect the hole wall morphology and surface roughness. No delamination or obvious scratches were found on the hole wall, and the hole wall roughness Sa value was 1.514 μm.

[0049] See also Figure 5 As shown, the comparison of using a twist drill to drill holes on a carbon fiber / bismaleimide composite material is shown. Figure 5 a is a top view of a hole machined in a carbon fiber / bismaleimide composite material using a twist drill. Figure 5 a is a cross-sectional inspection diagram of a hole machined in a carbon fiber / bismaleimide composite material using a twist drill. Figure 5 From a to b, it can be seen that there are serious damages such as delamination, tearing, burrs and scratches on the hole wall around the hole.

[0050] The present invention describes preferred embodiments and their effects. However, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0051] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for ultrasonic vibration-assisted hole grinding of carbon fiber / bismaleimide resin composite materials, characterized in that: The following steps are involved: The carbon fiber / bismaleimide resin-based composite material is cut into blocks, the surface is treated to be smooth, and the edges are polished to obtain a carbon fiber / bismaleimide resin-based composite material processing sample, and then the sample is clamped on a CNC machining center; Select an electroplated diamond abrasive hollow grinding head tool and install it on an ultrasonic tool holder with a vibration frequency of 30~40kHz; Connect the ultrasonic generator, ultrasonic tool holder and CNC machining center; Turn on the power supply and working switch of the ultrasonic generator, adjust the current value, and adjust the frequency of the ultrasonic generator to the frequency parameters required for processing, and dip water on the end of the tool with a brush. It can be seen that the water vibrates and atomizes, indicating that the vibration effect is in a resonant state; Use a laser displacement sensor to detect the vibration displacement of the tool end and adjust the tool overhang to achieve the maximum tool amplitude; The installed carbon fiber / bismaleimide resin-based composite material was subjected to ultrasonic vibration-assisted double-helix hole grinding, wherein the spindle speed was 3000~7000 r / min, the feed speed was 60~140 mm / min, the pitch was 0.1~0.3 mm / r, and the tool eccentricity was 1 mm; the hole grinding was completed.

2. The method for ultrasonic vibration-assisted hole grinding of carbon fiber / bismaleimide resin composite materials according to claim 1, characterized in that: In the ultrasonic vibration-assisted double-helix hole grinding process of carbon fiber / bismaleimide resin-based composite materials, a dry machining method without adding coolant is adopted.

3. The ultrasonic vibration assisted hole grinding method of carbon fiber / bismaleimide resin composite material according to claim 1, characterized in that: During the ultrasonic vibration-assisted double-helix grinding process, the power of the ultrasonic vibration device is turned on.

4. The method for ultrasonic vibration-assisted hole grinding of carbon fiber / bismaleimide resin composite material according to claim 1, characterized in that: The tool parameters are as follows: tool outer diameter 4 mm, tool inner diameter 2.6 mm, tool bar total length 50 mm, and sand plating length 5 mm.

5. The method for ultrasonic vibration-assisted hole grinding of carbon fiber / bismaleimide resin composite material according to claim 1, characterized in that: When the tool overhang is adjusted to the maximum tool amplitude, the amplitude is 11 μm when the overhang is 26 mm.

6. The method for ultrasonic vibration-assisted hole grinding of carbon fiber / bismaleimide resin composite material according to claim 1, characterized in that: Alicona Infinite Focus G4 fully automatic scanner was used to detect the entrance and exit morphologies of the holes after ultrasonic vibration assisted spiral grinding of carbon fiber / bismaleimide resin composite materials. Image software was used to calculate the area of ​​the outlet tearing zone. Alicona Infinite Focus G4 fully automatic scanner was used to detect the hole wall morphology and surface roughness.

7. The method for ultrasonic vibration-assisted hole grinding of carbon fiber / bismaleimide resin composite material according to claim 6, characterized in that: The non-dominated sorting genetic algorithm was used to perform multi-objective optimization of process parameters for three index parameters: hole wall roughness, outlet tear area, and material removal rate. The outlet tear area was less than 0.5 mm. 2 , the hole wall roughness Sa value is less than 2.1 μm, and the single hole processing time is shortened to 1.2-1.8 seconds.

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