Carbon fiber processing alloy milling cutter and production process

Abstract

The application relates to the technical field of alloy milling cutters, and particularly discloses a carbon fiber processing alloy milling cutter and a production process, which comprises a cutter body, the cutter body comprises first cutting teeth, second cutting teeth, third cutting teeth and fourth cutting teeth, and first chip removal grooves and second chip removal grooves are arranged on the cutter body; the symmetrical arrangement of the first cutting teeth and the third cutting teeth and the second cutting teeth and the fourth cutting teeth can inhibit processing vibration, the first cutting teeth and the third cutting teeth constitute a reverse cutting force couple, the cutting vibration amplitude and the layering risk can be reduced, the second cutting teeth and the fourth cutting teeth can inhibit material layering. Moreover, the first cutting teeth and the third cutting teeth enhance the axial cutting force, the second cutting teeth and the fourth cutting teeth can be subjected to secondary micro-cutting, the cutting chips can reduce scratching of the machined surface, the first chip removal grooves and the second chip removal grooves improve the discharge efficiency, and tool overheating or material layering caused by chip accumulation can be avoided.

Description

Technical Field

[0001] This application relates to the field of alloy end mill technology, and in particular to an alloy end mill for carbon fiber machining and its manufacturing process. Background Technology

[0002] Carbon fiber machining alloy end mills are high-efficiency precision cutting tools specifically designed for cutting high-hardness, high-wear-resistant composite materials. They are mainly used in aerospace, new energy vehicles, and high-end mold manufacturing, for machining high-performance materials such as carbon fiber reinforced resin matrix composites and carbon fiber / epoxy resin laminates. These materials are lightweight and high-strength, but due to their weak interlayer bonding, high hardness, and significant anisotropy, they are prone to defects such as delamination, burrs, and fiber pull-out during machining, placing stringent requirements on the geometry, edge strength, and thermal management performance of the cutting tools.

[0003] In the existing technology, most alloy end mills for carbon fiber processing adopt a single helical edge structure with a helix angle fixed in the range of 10° to 15°. The cutting edge is arranged in a continuous straight line or a gradually changing curve. The number of cutting teeth is mostly 2-4 teeth. The axial force is concentrated during cutting. The cutter body is covered with a traditional TiN coating. A drill bit is set on the cutter body. The drill bit is a simple conical shape with a tip angle of 60° to 90°. Chip removal grooves are also opened on the cutter body. The helix angle and number of chip removal grooves are the same as those of the helical edge.

[0004] Regarding the aforementioned technologies, when processing carbon fiber, the single helix can easily cause a sudden change in interlayer shear stress, leading to material delamination or tearing. Simultaneously, the lack of high-performance coatings or the use of only traditional TiN coatings results in low microhardness and poor bonding strength, making the coating prone to peeling off during high-speed cutting. This exposes the cemented carbide matrix directly into contact with the hard abrasive grains in the carbon fiber, accelerating edge wear. Furthermore, the chip groove design of single-helix cutting tools is relatively simple, making it easy for carbon fiber chips to entangle and clump together. Therefore, improvements are needed. Summary of the Invention

[0005] In order to improve the above-mentioned problems of alloy end mills for carbon fiber processing, this application provides an alloy end mill for carbon fiber processing and a manufacturing process thereof.

[0006] The first aspect of this application provides a carbon fiber machining alloy end mill, which adopts the following technical solution:

[0007] A carbon fiber machining alloy end mill includes a shank and a cutter body, characterized in that: the cutter body includes a cutting section and a drilling section, the sidewall of the cutting section is circumferentially provided with a first cutting tooth, a second cutting tooth, a third cutting tooth and a fourth cutting tooth, the first cutting tooth and the third cutting tooth are symmetrically arranged along the axis of the cutting section, the first cutting tooth and the third cutting tooth are both multiple sets of helical edges, the first cutting tooth is right-handed and the third cutting tooth is left-handed, and the tangential ratio angle of the first cutting tooth and the third cutting tooth is 95°;

[0008] The second cutting tooth and the fourth cutting tooth are symmetrically arranged along the axis of the cutting part. Both the second cutting tooth and the fourth cutting tooth have multiple sets of corrugated edges. The second cutting tooth is right-handed and the fourth cutting tooth is left-handed. The second cutting tooth and the fourth cutting tooth are respectively arranged between the first cutting tooth and the third cutting tooth. The tangential ratio angle of the second cutting tooth and the fourth cutting tooth is 85°.

[0009] A first chip removal groove is provided between the first cutting tooth and the second cutting tooth, and between the third cutting tooth and the fourth cutting tooth; a second chip removal groove is provided between the second cutting tooth and the third cutting tooth, and between the fourth cutting tooth and the first cutting tooth.

[0010] The drilling section is provided with a guide groove to facilitate the entry of cuttings into the first and second cuttings removal grooves during drilling.

[0011] By adopting the above technical solution, the symmetrical alternating arrangement of the first and third cutting teeth with the second and fourth cutting teeth achieves a balanced distribution of cutting force and suppresses machining vibration. Compared with the traditional unidirectional spiral blade, the first cutting tooth of the right-hand 95° spiral blade and the third cutting tooth of the left-hand 95° spiral blade form a reverse cutting force couple, forming a self-balancing system in the axial direction, which can further reduce the cutting vibration amplitude. It also generates a reverse torque during axial cutting to offset the radial tearing force during carbon fiber interlayer peeling and reduce the risk of delamination. The wavy cutting edges of the second cutting tooth of the right-hand 85° corrugated blade and the fourth cutting tooth of the left-hand 85° blade generate a pulsed cutting effect at the microscopic level, making the interlayer shear force of carbon fiber uniformly distributed and further suppressing material delamination.

[0012] Furthermore, the first and third cutting teeth are helical blades with opposite directions and a tangential ratio angle of 95°, which enhances the axial cutting force. The second and fourth cutting teeth are corrugated blades with a tangential ratio angle of 85°, which can perform secondary micro-cutting in the helical blade cutting gap. This ensures that the chip size is controllable and forms a micro-chip storage space through the corrugated structure of the cutting edge, reducing the scratches of the processed surface by the chips. The two work together to improve the material removal rate. The first chip removal groove, the second chip removal groove and the drilling guide groove form a continuous chip removal channel, which improves the efficiency of carbon fiber chip removal and avoids tool overheating or material delamination caused by chip accumulation.

[0013] Optionally, the second cutting tooth includes a first corrugated tooth and a second corrugated tooth, which are alternately arranged. The first corrugated tooth has a helix angle of 70° and the second corrugated tooth has a helix angle of 63°. The third cutting tooth includes a third corrugated tooth and a fourth corrugated tooth, which are alternately arranged. The third corrugated tooth has a helix angle of 66° and the fourth corrugated tooth has a helix angle of 60°.

[0014] By adopting the above technical solution, the corrugated teeth with helix angles of 70° and 63° are interlaced in the second cutting tooth, and the corrugated teeth with helix angles of 66° and 60° are interlaced in the fourth cutting tooth, forming an asymmetric cutting force distribution, suppressing harmonic resonance, dispersing the vibration frequency to multiple frequency bands, avoiding the natural frequency of the carbon fiber plate, reducing amplitude and processing noise, and the gradual reduction of the helix angle gradient can gradually reduce the cutting resistance, making the interlayer shear of carbon fiber smoother and reducing the surface roughness of the processed surface.

[0015] Optionally, the helix angle of both the first cutting tooth and the third cutting tooth is 5°.

[0016] By adopting the above technical solution, compared with the conventional 15° helix angle, the axial cutting force is reduced, avoiding delamination or tearing of carbon fiber laminates during processing, and the cutting edge rigidity is enhanced. It is suitable for intermittent cutting of carbon fibers and reduces the chipping rate of the cutting edge.

[0017] Optionally, the first cutting tooth is provided with a first chip breaker groove, and the third cutting tooth is provided with a second chip breaker groove. The helix angle of the first chip breaker groove and the second chip breaker groove is 20°. The first chip breaker groove is left-handed, and the second chip breaker groove is right-handed.

[0018] By adopting the above technical solution, the first chip breaker groove is engaged with the first cutting tooth in reverse, and the second chip breaker groove is engaged with the third cutting tooth in reverse. The intersection points of the first chip breaker groove and the second chip breaker groove with the first cutting tooth and the third cutting tooth respectively form "mechanical weak zones". By utilizing the sudden change effect of cutting force, the chip is forced to break periodically during the cutting process, shortening the chip length and reducing the risk of entanglement. The helix angles of the first chip breaker groove and the second chip breaker groove form an angle with the main cutting edge of the first cutting tooth and the second cutting tooth respectively, enhancing the local strength of the first cutting tooth and the second cutting tooth, and guiding the chip to curl and be discharged towards the chip removal groove.

[0019] Optionally, multiple sets of the first chip breaker groove and the second chip breaker groove are provided. The distance between adjacent first chip breaker grooves and adjacent second chip breaker grooves is 5 mm. Each set of first chip breaker grooves intersects with at least four sets of first cutting teeth, and each set of second chip breaker grooves intersects with at least four sets of third cutting teeth.

[0020] By adopting the above technical solution, the distance between adjacent first chip breaker grooves and adjacent second chip breaker grooves is 5mm, which enables forced chip breaker to be cut off in the early stage of chip formation, effectively controlling chip length. Furthermore, each set of first chip breaker grooves intersects with at least four sets of first cutting teeth, and each set of second chip breaker grooves intersects with at least four sets of third cutting teeth, ensuring that the first and second chip breaker grooves trigger chip breaking actions four times within one revolution of the tool. This achieves high-frequency chip breaking, reduces the contact time between the chip and the tool, and reduces the accumulation of cutting heat.

[0021] Optionally, the blade body surface is coated with a multi-layer titanium-based composite coating, and the handle and blade body are made of WC-Co cemented carbide. The multi-layer titanium-based composite coating includes a transition layer and a functional layer. The transition layer has a thickness of 0.5-1.2 μm and is composed of a gradient alloying layer of Ti and WC. The functional layer has a thickness of 1.5-3.8 μm, is composed of TiAlN, has a microhardness ≥2800 HV0.05, a surface roughness Ra≤0.15 μm, and a surface friction coefficient ≤0.25.

[0022] By adopting the above technical solution, the transition layer is a gradient alloying layer of pure Ti to Ti and WC. Due to the presence of WC in the tool body material, it can form a "chemical anchoring" effect with the transition layer, improving the bonding strength between the transition layer and the tool body. Furthermore, WC particles, as a reinforcing phase, are dispersed in the titanium, blocking the extension path of microcracks inside the coating, improving the coating toughness, and preventing coating peeling during high-speed cutting. The microhardness is ≥2800 HV0.05. Compared with uncoated tools, it can significantly suppress the wear of the cutting edge by silicide abrasive particles in carbon fiber. The surface roughness Ra≤0.15μm and the coefficient of friction≤0.25 can reduce cutting heat and extend tool life.

[0023] Optionally, the drilling section is provided in a pointed shape, the length of the drilling section is 3mm, the minimum length of the cutting section is 20mm, and the cross-section of the drilling section along its length is an isosceles right triangle.

[0024] By adopting the above technical solution, the drilling section length is 3mm, which shortens the overhang of the drilling section, suppresses the vibration at the moment of cutting, and avoids material edge chipping. The minimum cutting section length is 20mm, which can process typical carbon fiber laminates in one go, such as drone wing skin. The minimum cutting section length of 20mm can also disperse cutting heat and reduce the heat load per unit length. The cross-section of the drilling section along the length direction is an isosceles right triangle, which realizes low-resistance cutting of carbon fiber laminate materials and avoids material edge delamination. The cross-sectional shape matches the guide groove to form a directional chip guide channel and improve the initial chip discharge efficiency.

[0025] This application also provides a manufacturing process for a carbon fiber machining alloy end mill, including the following steps:

[0026] S1: Powder metallurgy tool body forming, using ultra-fine grain cemented carbide powder mixed with binder, and injection molding process to form an integrated blank of tool body and tool holder. After forming, it is degreased and vacuum sintered to obtain a matrix with a density ≥99.5% and a hardness ≥92HRA.

[0027] S2: Five-axis linkage grinding process, using diamond grinding wheels to perform precision grinding on the cutting part, respectively machining the first and third cutting teeth with a helix angle of 5°, the second cutting teeth with helix angles of 70° and 63°, and the fourth cutting teeth with helix angles of 66° and 60°. The guide groove is formed in the first and second chip removal grooves using electrical discharge forming process, and the drilling part is processed into an isosceles right triangle cross section by laser cutting;

[0028] S3: Edge passivation and chip breaking groove machining. The cutting edge band is passivated by magnetic grinding. Chip breaking grooves with a helix angle of 20° are machined at the positions of the first and second chip breaking grooves using an ultra-hard abrasive grinding wheel.

[0029] S4: Physical vapor deposition coating preparation: The blade is placed in a vacuum furnace and cleaned by argon ion bombardment to remove surface impurities. Ti target and Ar gas are introduced, and a gradient Ti alloy layer is deposited on the WC-Co substrate at a temperature of 450℃. The composition gradually changes from pure Ti to Ti-20%WC. The target is then switched to TiAl, N2 is introduced, and a TiAlN coating is deposited under a pulsed bias voltage of -100V. The microhardness is controlled to be ≥2800 HV0.05, the surface roughness Ra≤0.15μm, and the coating surface is polished by ion beam to make the coefficient of friction ≤0.25.

[0030] S5: Perform dynamic balancing correction at a tool dynamic balancing machine speed of 20000rpm, with residual unbalance ≤0.5g·mm. Use a white light interferometer to detect the uniformity of coating thickness, verify the cutting edge geometry parameters with a laser confocal microscope, and simulate cutting tests.

[0031] S6: After the simulated cutting test is passed, the non-cutting area of ​​the tool is sealed with an anti-oxidation wax coating, and the specifications and batch number are engraved on the tool holder by laser marking process, with a character depth of 0.1mm±0.02mm.

[0032] In summary, this application includes at least one of the following beneficial technical effects:

[0033] 1. The symmetrical alternating arrangement of the first and third cutting teeth with the second and fourth cutting teeth achieves a balanced distribution of cutting force and suppresses machining vibration. The symmetrically arranged right-handed 95° spiral cutting edge of the first cutting tooth and the left-handed 95° spiral cutting edge of the third cutting tooth form a reverse cutting force couple, forming a self-balancing system in the axial direction, which can further reduce the cutting vibration amplitude. It also generates a reverse torque during axial cutting to offset the radial tearing force during carbon fiber interlayer peeling and reduce the risk of delamination. The wavy cutting edges of the right-handed 85° corrugated cutting edge of the second cutting tooth and the left-handed 85° corrugated cutting edge of the fourth cutting tooth generate a pulsed cutting effect at the micro level, making the interlayer shear force of carbon fiber uniformly distributed and further suppressing material delamination.

[0034] 2. The first and third cutting teeth are helical blades with opposite directions and a tangential ratio angle of 95°, which enhances the axial cutting force. The second and fourth cutting teeth are corrugated blades with a tangential ratio angle of 85°. Secondary micro-cutting can be performed in the gap between the helical blades, which not only ensures that the chip size is controllable, but also forms a micro-chip storage space through the corrugated structure of the cutting edge, reducing the scratches of the processed surface by the chips. The two work together to improve the material removal rate. The first chip removal groove, the second chip removal groove and the drilling guide groove form a continuous chip removal channel, which improves the efficiency of carbon fiber chip removal and avoids tool overheating or material delamination caused by chip accumulation.

[0035] 3. The corrugated teeth with helix angles of 70° and 63° are interlaced in the second cutting tooth, and the corrugated teeth with helix angles of 66° and 60° are interlaced in the fourth cutting tooth, forming an asymmetric cutting force distribution, suppressing harmonic resonance, dispersing the vibration frequency to multiple frequency bands, avoiding the natural frequency of the carbon fiber plate, reducing amplitude and processing noise. The gradual decrease in helix angle can gradually reduce cutting resistance, making the interlayer shear of carbon fiber smoother and reducing the surface roughness of the machined surface.

[0036] 4. The first chip breaker groove is in reverse engagement with the first cutting tooth, and the second chip breaker groove is in reverse engagement with the third cutting tooth. The intersection points of the first and second chip breaker grooves with the first and third cutting teeth respectively form "mechanically weak zones". By utilizing the sudden change effect of cutting force, the chips are forced to break periodically during the cutting process, shortening the chip length and reducing the risk of entanglement. The helix angles of the first and second chip breaker grooves form an angle with the main cutting edge of the first and second cutting teeth respectively, enhancing the local strength of the first and second cutting teeth, and guiding the chips to curl and be discharged towards the chip removal groove.

[0037] 5. The spacing between adjacent first and second chip breaker grooves is 5mm, which enables the chips to be cut off in the early stage of formation, effectively controlling the chip length. Furthermore, each set of first chip breaker grooves intersects with at least four sets of first cutting teeth, and each set of second chip breaker grooves intersects with at least four sets of third cutting teeth, ensuring that the first and second chip breaker grooves trigger chip breaking four times within one revolution of the tool. This achieves high-frequency chip breaking, reduces the contact time between the chip and the tool, and reduces the accumulation of cutting heat.

[0038] 6. The transition layer is a gradient alloy layer that transitions from pure Ti to Ti and WC. Due to the presence of WC in the tool body material, it can form a "chemical anchoring" effect with the transition layer, improving the bonding strength between the transition layer and the tool body. Furthermore, WC particles, as a reinforcing phase, are dispersed in the titanium, blocking the extension path of microcracks inside the coating, improving the coating toughness, and preventing coating peeling during high-speed cutting. The microhardness is ≥2800 HV0.05. Compared with uncoated tools, it can significantly suppress the wear of the cutting edge by silicide abrasive particles in carbon fiber. The surface roughness Ra≤0.15μm and the coefficient of friction≤0.25 can reduce cutting heat and extend tool life. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the overall structure of the alloy end mill in the embodiments of this application;

[0041] Figure 2 yes Figure 1 Another perspective;

[0042] Figure 3 yes Figure 2 Another perspective;

[0043] Figure 4 yes Figure 3Another perspective;

[0044] Figure 5 yes Figure 4 Another perspective;

[0045] Figure 6 yes Figure 5 Another perspective.

[0046] Reference numerals: 1. Tool holder; 2. Tool body; 21. Cutting section; 211. First cutting tooth; 212. Second cutting tooth; 213. Third cutting tooth; 214. Fourth cutting tooth; 22. Drilling section; 23. First chip removal groove; 24. Second chip removal groove; 25. Guide groove; 3. First chip breaking groove; 4. Second chip breaking groove. Detailed Implementation

[0047] The following is in conjunction with the appendix Figure 1-6 This application will be described in further detail.

[0048] This application discloses an alloy end mill for carbon fiber machining. (Refer to...) Figure 1 and Figure 2 A carbon fiber machining alloy end mill includes a shank 1 and a cutter body 2. The shank 1 and cutter body 2 are made of WC-Co cemented carbide and are integrally formed. The cutter body 2 includes a cutting section 21 and a drilling section 22. The side wall of the cutting section 21 is circumferentially provided with a first cutting tooth 211, a second cutting tooth 212, a third cutting tooth 213 and a fourth cutting tooth 214. The first cutting tooth 211 and the third cutting tooth 213 are symmetrically arranged along the axis of the cutting section 21. The first cutting tooth 211 and the third cutting tooth 213 are both multi-set helical edges, and the first cutting tooth 211 is right-handed and the third cutting tooth 213 is left-handed. The tangential ratio angle of the first cutting tooth 211 and the third cutting tooth 213 is 95°.

[0049] The second cutting tooth 212 and the fourth cutting tooth 214 are symmetrically arranged along the axis of the cutting part 21. Both the second cutting tooth 212 and the fourth cutting tooth 214 have multiple sets of corrugated edges. The second cutting tooth 212 is right-handed and the fourth cutting tooth 214 is left-handed. The second cutting tooth 212 and the fourth cutting tooth 214 are respectively arranged between the first cutting tooth 211 and the third cutting tooth 213. The tangential ratio angle of the second cutting tooth 212 and the fourth cutting tooth 214 is 85°.

[0050] The cutting part 21 is integrally disposed on the tool holder 1, and the drilling part 22 is integrally disposed on the end of the cutting part 21 away from the tool holder 1. A first chip removal groove 23 is provided between the first cutting tooth 211 and the second cutting tooth 212, the third cutting tooth 213 and the fourth cutting tooth 214, and a second chip removal groove 24 is provided between the second cutting tooth 212 and the third cutting tooth 213, the fourth cutting tooth 214 and the first cutting tooth 211. The drilling part 22 is provided in a pointed shape, and a guide groove 25 is provided on the drilling part 22 to facilitate the entry of chips into the first chip removal groove 23 and the second chip removal groove 24 during drilling.

[0051] The symmetrical alternating arrangement of the first cutting tooth 211, the third cutting tooth 213, the second cutting tooth 212, and the fourth cutting tooth 214 achieves a balanced distribution of cutting force and suppresses machining vibration. Compared with the traditional unidirectional spiral blade, the first cutting tooth 211 of the right-hand spiral blade and the third cutting tooth 213 of the left-hand spiral blade, which are symmetrically arranged, form a reverse cutting force couple and create a self-balancing system in the axial direction. This can further reduce the amplitude of cutting vibration and generate a reverse torque during axial cutting to offset the radial tearing force during carbon fiber interlayer peeling and reduce the risk of delamination. The wavy cutting edges of the second cutting tooth 212 of the right-hand spiral blade and the fourth cutting tooth 214 of the left-hand spiral blade generate a pulsed cutting effect at the microscopic level, making the interlayer shear force of carbon fiber evenly distributed and further suppressing material delamination.

[0052] Furthermore, the first cutting tooth 211 and the third cutting tooth 213 are helical blades with opposite directions and a tangential ratio angle of 95°, which enhances the axial cutting force. The second cutting tooth 212 and the fourth cutting tooth 214 are corrugated blades with a tangential ratio angle of 85°, which can perform secondary micro-cutting in the helical blade cutting gap. This ensures that the chip size is controllable and forms a micro-chip storage space through the corrugated structure of the cutting edge, reducing the scratches of the processed surface by the chips. The two work together to improve the material removal rate. The first chip removal groove 23, the second chip removal groove 24 and the guide groove 25 of the drilling part 22 form a continuous chip removal channel, which improves the efficiency of carbon fiber chip removal and avoids tool overheating or material delamination caused by chip accumulation.

[0053] Reference Figure 4 and Figure 6 In this embodiment, the second cutting tooth 212 includes a first corrugated tooth and a second corrugated tooth, which are alternately arranged. The helix angle of the first corrugated tooth is 70° and the helix angle of the second corrugated tooth is 63°. The third cutting tooth 213 includes a third corrugated tooth and a fourth corrugated tooth, which are alternately arranged. The helix angle of the third corrugated tooth is 66° and the helix angle of the fourth corrugated tooth is 60°.

[0054] The corrugated teeth with helix angles of 70° and 63° are interlaced in the second cutting tooth 212, and the corrugated teeth with helix angles of 66° and 60° are interlaced in the fourth cutting tooth 214, forming an asymmetric cutting force distribution, suppressing harmonic resonance, dispersing the vibration frequency to multiple frequency bands, avoiding the natural frequency of the carbon fiber plate, reducing amplitude and processing noise. The gradual decrease in helix angle can gradually reduce cutting resistance, making the interlayer shear of carbon fiber smoother and reducing the surface roughness of the machined surface.

[0055] Reference Figure 3 and Figure 5 The first cutting tooth 211 and the third cutting tooth 213 both have a helix angle of 5°. Compared to the conventional 15° helix angle, this reduces the axial cutting force, prevents delamination or tearing of the carbon fiber laminate during machining, and enhances the edge rigidity, making it suitable for intermittent cutting of carbon fibers and reducing the chipping rate. The first cutting tooth 211 has a first chip breaker groove 3, and the third cutting tooth 213 has a second chip breaker groove 4. The helix angle of both the first chip breaker groove 3 and the second chip breaker groove 4 is 20°, with the first chip breaker groove 3 being left-handed and the second chip breaker groove 4 being right-handed.

[0056] The first chip breaker groove 3 is in reverse engagement with the first cutting tooth 211, and the second chip breaker groove 4 is in reverse engagement with the third cutting tooth 213. The intersection points of the first chip breaker groove 3 and the second chip breaker groove 4 with the first cutting tooth 211 and the third cutting tooth 213 respectively form "mechanically weak zones". By utilizing the sudden change effect of cutting force, the chips are forced to break periodically during the cutting process, shortening the chip length and reducing the risk of entanglement. The helix angles of the first chip breaker groove 3 and the second chip breaker groove 4 form an angle with the main cutting edge of the first cutting tooth 211 and the second cutting tooth 212 respectively, enhancing the local strength of the first cutting tooth 211 and the second cutting tooth 212, and guiding the chips to curl and be discharged towards the chip removal groove.

[0057] Reference Figure 3 and Figure 5 Multiple sets of the first chip breaker groove 3 and the second chip breaker groove 4 are provided. The distance between adjacent first chip breaker grooves 3 and adjacent second chip breaker grooves 4 is 5 mm. Each set of first chip breaker grooves 3 intersects with at least four sets of first cutting teeth 211, and each set of second chip breaker grooves 4 intersects with at least four sets of third cutting teeth 213. The 5 mm distance between adjacent first chip breaker grooves 3 and adjacent second chip breaker grooves 4 ensures that the first chip breaker grooves 3 and the second chip breaker grooves 4 trigger chip breaking four times within one revolution of the tool, achieving high-frequency chip breaking, reducing the contact time between the chip and the tool, and reducing the accumulation of cutting heat.

[0058] The surface of the blade body 2 is coated with a multi-layer titanium-based composite coating, which includes a transition layer and a functional layer. The thickness of the transition layer is 0.5-1.2μm, and its composition is a gradient alloying layer of Ti and the matrix material. The thickness of the functional layer is 1.5-3.8μm, its composition is TiAlN, its microhardness is ≥2800 HV0.05, its surface roughness Ra≤0.15μm, and its surface friction coefficient is ≤0.25.

[0059] The transition layer is a gradient alloying layer that transitions from pure Ti to Ti and WC. Due to the presence of WC in the tool body 2 material, it can form a "chemical anchoring" effect with the transition layer, improving the bonding strength between the transition layer and the tool body 2. Furthermore, WC particles, as a reinforcing phase, are dispersed in the titanium, blocking the extension path of microcracks inside the coating, improving the coating toughness, and preventing coating peeling during high-speed cutting. The microhardness is ≥2800 HV0.05. Compared with uncoated tools, it can significantly suppress the wear of the cutting edge by silicide abrasive particles in carbon fiber. The surface roughness Ra≤0.15μm and the coefficient of friction≤0.25 can reduce cutting heat and extend tool life.

[0060] Reference Figure 3 and Figure 4 The drilling section 22 has a length of 3mm, and the cutting section 21 has a minimum length of 20mm. The cross-section of the drilling section 22 along its length is an isosceles right triangle. The 3mm length of the drilling section 22 reduces its overhang, suppressing vibration during cutting and preventing edge chipping. The minimum length of the cutting section 21 (20mm) allows for one-time processing of typical carbon fiber laminates, such as drone wing skins. The minimum length of the cutting section 21 also disperses cutting heat, reducing the heat load per unit length. The isosceles right triangle cross-section of the drilling section 22 along its length enables low-resistance cutting of the carbon fiber laminate, preventing edge delamination. The cross-sectional shape matches the guide groove 25, forming a directional chip flow channel and improving initial chip removal efficiency.

[0061] The implementation principle of the carbon fiber machining alloy end mill in Embodiment 1 of this application is as follows:

[0062] When it is necessary to suppress material delamination, the symmetrical alternating arrangement of the first cutting tooth 211, the third cutting tooth 213, the second cutting tooth 212, and the fourth cutting tooth 214 achieves a balanced distribution of cutting force and suppresses machining vibration. The symmetrically arranged right-handed 95° helical blade of the first cutting tooth 211 and the left-handed 95° helical blade of the third cutting tooth 213 form a reverse cutting force couple, forming a self-balancing system in the axial direction, which can further reduce the cutting vibration amplitude. It also generates a reverse torque during axial cutting to offset the radial tearing force during carbon fiber interlayer peeling and reduce the risk of delamination. The wavy cutting edges of the right-handed 85° corrugated blade of the second cutting tooth 212 and the left-handed 85° corrugated blade of the fourth cutting tooth 214 generate a pulsed cutting effect at the microscopic level, making the interlayer shear force of carbon fiber uniformly distributed and further suppressing material delamination.

[0063] When it is necessary to avoid excessively long chips from affecting the use of the milling cutter itself, the first chip breaker groove 3 is in reverse engagement with the first cutting tooth 211, and the second chip breaker groove 4 is in reverse engagement with the third cutting tooth 213. The intersection points of the first chip breaker groove 3 and the second chip breaker groove 4 with the first cutting tooth 211 and the third cutting tooth 213 respectively form "mechanically weak zones". By utilizing the sudden change effect of cutting force, the chip is forced to break periodically during the cutting process, shortening the chip length and reducing the risk of entanglement. The helix angles of the first chip breaker groove 3 and the second chip breaker groove 4 form an angle with the main cutting edge of the first cutting tooth 211 and the second cutting tooth 212 respectively, enhancing the local strength of the first cutting tooth 211 and the second cutting tooth 212, while guiding the chip to curl and be discharged towards the chip removal groove.

[0064] When it is necessary to improve the strength of the coating on the end mill, the transition layer is a gradient alloying layer of pure Ti to Ti and WC. Due to the presence of WC in the material of the cutter body 2, a "chemical anchoring" effect can be formed with the transition layer, which improves the bonding strength between the transition layer and the cutter body 2. In addition, WC particles, as a reinforcing phase, are dispersed in titanium, blocking the extension path of microcracks inside the coating, improving the coating toughness, and preventing the coating from peeling off during high-speed cutting. The microhardness is ≥2800 HV0.05. Compared with uncoated tools, it can significantly suppress the wear of the cutting edge by silicide abrasive grains in carbon fiber. The surface roughness Ra≤0.15μm and the coefficient of friction≤0.25 can reduce cutting heat and extend tool life.

[0065] This embodiment also provides a manufacturing process for carbon fiber machining alloy end mills, including the following steps:

[0066] S1: Powder metallurgy tool body 2 is formed by mixing ultra-fine grain cemented carbide powder with binder and then using injection molding to form an integrated blank of tool body 2 and tool holder 1. After forming, it is degreased and vacuum sintered to obtain a matrix with a density of ≥99.5% and a hardness of ≥92HRA.

[0067] S2: Five-axis linkage grinding process, using diamond grinding wheels to perform precision grinding on the cutting part 21, respectively machining the first cutting tooth 211 and the third cutting tooth 213 with a helix angle of 5°, the second cutting tooth 212 with helix angles of 70° and 63° and the fourth cutting tooth 214 with helix angles of 66° and 60°, and forming the guide groove 25 in the first chip removal groove 23 and the second chip removal groove 24 using the electric discharge forming process, and machining the drilling part 22 into an isosceles right-angled triangular cross section by laser cutting;

[0068] S3: Edge passivation and chip breaking groove machining. The cutting edge band is passivated by magnetic grinding process. Chip breaking grooves with a helix angle of 20° are machined at the positions of the first chip breaking groove 3 and the second chip breaking groove 4 using an ultra-hard abrasive grinding wheel.

[0069] S4: Physical vapor deposition coating preparation: The blade body 2 is placed in a vacuum furnace and cleaned by argon ion bombardment to remove surface impurities. Ti target and Ar gas are introduced, and a gradient Ti alloy layer is deposited on the WC-Co substrate material at a temperature of 450℃. The composition gradually changes from pure Ti to Ti-20%WC. The TiAl target is then switched to, and N2 is introduced. TiAlN coating is deposited under a pulsed bias voltage of -100V. The microhardness is controlled to be ≥2800 HV0.05, the surface roughness Ra≤0.15μm, and the coating surface is polished by ion beam to make the coefficient of friction ≤0.25.

[0070] S5: Perform dynamic balancing correction at a tool dynamic balancing machine speed of 20000rpm, with residual unbalance ≤0.5g·mm. Use a white light interferometer to detect the uniformity of coating thickness, verify the cutting edge geometry parameters with a laser confocal microscope, and simulate cutting tests.

[0071] S6: After the simulated cutting test is passed, the non-cutting area of ​​the tool is sealed with an anti-oxidation wax coating. The specifications and batch number are engraved on the tool holder 1 by laser marking process, with a character depth of 0.1mm±0.02mm.

[0072] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," "third," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms "an" or "a" and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms "comprising" or "including" and similar terms mean that the elements or objects preceding "comprising" or "including" encompass the elements or objects listed following "comprising" or "including" and their equivalents, and do not exclude other elements or objects. "Above," "below," "left," "right," etc., are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0073] The above are all optional embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A carbon fiber machining alloy end mill, comprising a shank and a cutter body, characterized in that: The cutter body includes a cutting section and a drilling section. The sidewall of the cutting section is circumferentially provided with a first cutting tooth, a second cutting tooth, a third cutting tooth and a fourth cutting tooth. The first cutting tooth and the third cutting tooth are symmetrically arranged along the axis of the cutting section. The first cutting tooth and the third cutting tooth are both multiple sets of helical blades. The first cutting tooth is right-handed and the third cutting tooth is left-handed. The tangential ratio angle of the first cutting tooth and the third cutting tooth is 95°. The second cutting tooth and the fourth cutting tooth are symmetrically arranged along the axis of the cutting part. Both the second cutting tooth and the fourth cutting tooth have multiple sets of corrugated edges. The second cutting tooth is right-handed and the fourth cutting tooth is left-handed. The second cutting tooth and the fourth cutting tooth are respectively arranged between the first cutting tooth and the third cutting tooth. The tangential ratio angle of the second cutting tooth and the fourth cutting tooth is 85°. A first chip removal groove is provided between the first cutting tooth and the second cutting tooth, and between the third cutting tooth and the fourth cutting tooth; a second chip removal groove is provided between the second cutting tooth and the third cutting tooth, and between the fourth cutting tooth and the first cutting tooth. The drilling section is provided with a guide groove for facilitating the entry of cuttings into the first and second cuttings removal grooves during drilling. The second cutting tooth includes a first corrugated tooth and a second corrugated tooth, which are alternately arranged. The helix angle of the first corrugated tooth is 70° and the helix angle of the second corrugated tooth is 63°. The third cutting tooth includes a third corrugated tooth and a fourth corrugated tooth, which are alternately arranged. The helix angle of the third corrugated tooth is 66° and the helix angle of the fourth corrugated tooth is 60°.

2. The carbon fiber machining alloy end mill according to claim 1, characterized in that: The helix angle of both the first cutting tooth and the third cutting tooth is 5°.

3. The carbon fiber machining alloy end mill according to claim 2, characterized in that: The first cutting tooth has a first chip breaker groove, and the third cutting tooth has a second chip breaker groove. The helix angle of the first chip breaker groove and the second chip breaker groove is 20°. The first chip breaker groove is left-handed, and the second chip breaker groove is right-handed.

4. The carbon fiber machining alloy end mill according to claim 3, characterized in that: Both the first chip breaker groove and the second chip breaker groove have multiple sets. The distance between adjacent first chip breaker grooves and adjacent second chip breaker grooves is 5mm. Each set of first chip breaker grooves intersects with at least four sets of first cutting teeth, and each set of second chip breaker grooves intersects with at least four sets of third cutting teeth.

5. A carbon fiber machining alloy end mill according to claim 1, characterized in that: The handle and the blade body are made of WC-Co cemented carbide. The blade body surface is coated with a multi-layer titanium-based composite coating, which includes a transition layer and a functional layer. The transition layer has a thickness of 0.5-1.2 μm and is composed of a gradient alloying layer of Ti and WC. The functional layer has a thickness of 1.5-3.8 μm, is composed of TiAlN, has a microhardness ≥2800 HV0.05, a surface roughness Ra≤0.15 μm, and a surface friction coefficient ≤0.

25.

6. The carbon fiber machining alloy end mill according to claim 1, characterized in that: The drilling section is pointed in shape, the length of the drilling section is 3mm, the minimum length of the cutting section is 20mm, and the cross-section of the drilling section along its length is an isosceles right triangle.

7. A manufacturing process for a carbon fiber machining alloy end mill, based on the carbon fiber machining alloy end mill as described in any one of claims 1-6, characterized in that: Includes the following steps: S1: Powder metallurgy blade forming, using ultra-fine grain cemented carbide powder mixed with binder, and injection molding process to form an integrated blank of blade body and handle, after which degreasing and vacuum sintering are performed to obtain WC-Co matrix material with a density ≥99.5% and a hardness ≥92HRA; S2: Five-axis linkage grinding process, using diamond grinding wheels to perform precision grinding on the cutting part, respectively machining the first and third cutting teeth with a helix angle of 5°, the second cutting teeth with helix angles of 70° and 63°, and the fourth cutting teeth with helix angles of 66° and 60°. The guide groove is formed in the first and second chip removal grooves using electrical discharge forming process, and the drilling part is processed into an isosceles right triangle cross section by laser cutting; S3: Edge passivation and chip breaking groove machining. The cutting edge band is passivated by magnetic grinding. Chip breaking grooves with a helix angle of 20° are machined at the positions of the first and second chip breaking grooves using an ultra-hard abrasive grinding wheel. S4: Physical vapor deposition coating preparation: The blade is placed in a vacuum furnace and cleaned by argon ion bombardment to remove surface impurities. Ti target and Ar gas are introduced, and a gradient Ti alloy layer is deposited on the WC-Co substrate at a temperature of 450℃. The composition gradually changes from pure Ti to Ti-20%WC. The target is then switched to TiAl, N2 is introduced, and a TiAlN coating is deposited under a pulsed bias voltage of -100V. The microhardness is controlled to be ≥2800 HV0.05, the surface roughness Ra≤0.15μm, and the coating surface is polished by ion beam to make the coefficient of friction ≤0.

25. S5: Perform dynamic balancing correction at a tool dynamic balancing machine speed of 20000rpm, with residual unbalance ≤0.5g·mm. Use a white light interferometer to detect the uniformity of coating thickness, verify the cutting edge geometry parameters with a laser confocal microscope, and simulate cutting tests. S6: After the simulated cutting test is passed, the non-cutting area of ​​the tool is sealed with an anti-oxidation wax coating. The specification parameters and batch number are engraved on the tool holder (1) by laser marking process, with a character depth of 0.1mm±0.02mm.

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