Rotary cutting tool with sawtooth-shaped cutting edge and preparation method of rotary cutting tool

Abstract

The invention discloses a rotary cutting tool with a zigzag cutting edge, which comprises a cutter body and is characterized in that a chip breaker groove is arranged on the front cutter surface of the cutter body, so that the zigzag cutting edge comprising a plurality of cutting teeth is formed on the cutting teeth, the groove surface of the chip breaker groove is provided with a cutting guide surface, and the cutting guide surface is provided with a plurality of cutting teeth. Therefore, cuttings can be guided into the cutter body chip containing groove or guided in the chip removal direction of the cutter body chip containing groove. The sawtooth-shaped cutting edge can effectively offset or balance cutting force, including axial cutting pressure, axial cutting tension and radial cutting force, from different directions, double dispersion of the cutting force and cutting heat is achieved, the temperature generated in the cutting process is reduced, the stability of the cutter in the machining process is greatly improved, and the service life of the cutter is prolonged. The service life of the cutter is prolonged, the machining efficiency and precision are remarkably improved, and a brand-new technical path is developed for machining of the metal thin-wall part.

Description

Technical Field

[0001] The present invention relates to the technical field of metal cutting, and in particular to a rotary cutting tool with a serrated cutting edge and a preparation method thereof. Background Art

[0002] The quality and performance of cutting tools have a vital impact on the processing accuracy, quality and efficiency of products. This problem is particularly prominent in the processing of aviation and aerospace parts. For example, the processing efficiency of difficult-to-process materials such as nickel-based alloys and titanium alloys is already low, and the parts become thinner due to lightweight design, which makes it easier to cause problems such as workpiece deformation during processing. In order to meet these challenges, the market has put forward higher requirements for cutting tool performance. In particular, the processing of thin-walled parts faces multiple challenges: they are prone to deformation due to uneven force, which in turn affects the accuracy of size and shape; they have low rigidity and are prone to vibration, which affects the quality and accuracy of the processed surface; they are difficult to clamp and fix, and are prone to deformation due to improper clamping force; they have poor heat dissipation capacity and are prone to local thermal deformation; mechanical stress and thermal stress may be introduced during processing, causing residual stress on the surface of the workpiece, which in turn affects its performance and service life; the finish and accuracy of the processed surface are difficult to guarantee, and problems such as uneven surface roughness and scratches are prone to occur; at the same time, thin-walled parts are very sensitive to cutting forces, and excessive cutting forces will cause deformation of the workpiece, further increasing the difficulty of processing. Therefore, it is particularly urgent to improve the performance of domestic cutting tools, and high-performance cutting tools that can solve these processing difficulties are urgently needed. Summary of the invention

[0003] The present invention provides a rotary cutting tool with a serrated cutting edge. The cutting tool aims to reduce and disperse cutting force, optimize chip removal performance, improve cutting efficiency, and extend tool life through its unique cutting edge design. The specific implementation methods include the following:

[0004] Embodiment 1: A rotary cutting tool with a serrated cutting edge, comprising a cutter body and an optional tool holder for direct or indirect connection with a machine tool, characterized in that the cutter body is provided with a plurality of cutter body chip grooves and cutting teeth corresponding to the cutter body chip grooves, the surface of the cutter body chip groove facing the cutting rotation direction is the cutter body rake face,

[0005] The tool body chip groove is a straight groove, and the tool body rake surface includes a plane,

[0006] or,

[0007] The tool body chip groove is a spiral groove, and the tool body rake surface includes a spiral surface,

[0008] A chip breaker groove is arranged on the front cutting face of the cutter body, so that a serrated edge including a plurality of cutting teeth is formed on the cutting tooth, and the serrated edges of at least two or all the cutting teeth on the same rotation center are located on the same cutting outer circle,

[0009] The groove surface of the chip breaker groove extends in the width direction of the front cutting edge of the tool body to an area not exceeding two-thirds, one-half or one-quarter of the width of the front cutting edge of the tool body.

[0010] or,

[0011] The groove surface of the chip breaker groove extends to an area of ​​two-thirds, one-half or more than one-quarter of the width of the front cutting edge of the tool body in the width direction of the front cutting edge of the tool body, and the groove surface of the chip breaker groove has a chip guiding surface, so that the chips can be guided into the chip groove of the tool body or the chips can be guided along the chip removal direction of the chip groove of the tool body.

[0012] Embodiment 2: The rotary cutting tool with a serrated cutting edge according to embodiment 1 is characterized in that the chip guiding surface is formed by a depression extending in the normal direction of the cutting edge or in the chip removal direction of the chip groove of the tool body, that is, the depression of the chip breaker groove extends in the normal direction of the corresponding cutting edge or in the chip removal direction of the chip groove of the tool body,

[0013] Optionally, the chip guiding surface further includes an arc transition surface between the bottom surface of the chip breaker groove and the front cutting edge of the tool body.

[0014] Embodiment 3: A rotary cutting tool with a serrated cutting edge according to embodiment 1, characterized in that the groove surface of the chip breaker groove has a first front angle surface intersecting with the outer peripheral surface of the tool body, and the first front angle surface forms a first front angle on the serrated cutting edge.

[0015] Embodiment 4, according to the rotary cutting tool with a serrated cutting edge described in embodiment 3, is characterized in that the chip breaker groove is only arranged at the depression of the serrated cutting edge, the groove surface of the chip breaker groove intersects with the outer peripheral surface of the tool body and forms a first rake angle at the depression of the serrated cutting edge.

[0016] Embodiment 5, according to the rotary cutting tool with a serrated cutting edge described in embodiment 3, it is characterized in that the groove surface of the chip breaker groove has a second rake angle surface connected to the first rake angle surface to form a second rake angle, and the second rake angle is larger than the corresponding first rake angle.

[0017] Embodiment 6: A rotary cutting tool with a serrated cutting edge according to embodiment 1, characterized in that the tooth pitch and / or tooth depth between the cutting teeth on the same cutting tooth is variable.

[0018] Embodiment 7: The rotary cutting tool with a serrated cutting edge according to embodiment 1 is characterized in that the tooth pitch and / or tooth depth of the cutting teeth between adjacent cutting teeth have different change patterns, so that adjacent serrated cutting edges are staggered with each other.

[0019] Embodiment 8: The rotary cutting tool with a serrated cutting edge according to embodiment 1 is characterized in that the cutting teeth between adjacent cutting teeth do not overlap with each other in the cutting rotation plane, so that adjacent serrated cutting edges are staggered with each other.

[0020] Embodiment 9: A rotary cutting tool with a serrated cutting edge according to embodiment 1, characterized in that the pitch of the cutting teeth is 5% to 25% of the diameter of the tool body.

[0021] Embodiment 10: A rotary cutting tool with a serrated cutting edge according to embodiment 1, characterized in that the angles between the cutting edges of different cutting teeth located in the same radial direction and the axis of the tool body are different.

[0022] Embodiment 11: A rotary cutting tool with a serrated cutting edge according to embodiment 1, characterized in that the chip groove of the tool body is a spiral groove, and at least part of the plurality of cutting teeth of the serrated cutting edge has a positive cutting edge segment, and the direction of the positive cutting edge segment is the same as the spiral direction of the spiral groove,

[0023] Furthermore, at least part of the multiple cutting teeth of the serrated edge have a reverse edge segment, the direction of the reverse edge segment is opposite to the spiral direction of the spiral groove, and the angle between the reverse edge segment and the axis of the tool body is greater than or equal to 0 degree and less than or equal to 75 degrees, for example, greater than or equal to 8 degrees and less than or equal to 60 degrees, for example, greater than or equal to 10 degrees and less than or equal to 50 degrees, for example, greater than or equal to 20 degrees and less than or equal to 40 degrees, for example, greater than or equal to 30 degrees and less than or equal to 45 degrees.

[0024] Embodiment 12, according to the rotary cutting tool with a serrated cutting edge described in embodiment 1, it is characterized in that the chip groove of the tool body is a spiral groove, at least part of the multiple cutting teeth of the serrated cutting edge have a vertical cutting edge segment, and the angle between the vertical cutting edge segment and the axis of the tool body is less than 8 degrees, for example, less than 5 degrees, for example, less than 3 degrees, for example, less than 2 degrees, for example, 0 degrees.

[0025] Embodiment 13, according to the rotary cutting tool with a serrated cutting edge described in Embodiment 1, it is characterized in that the rotary cutting tool with a serrated cutting edge has 2 to 8 cutting teeth, such as 4 to 6 cutting teeth, such as 6 to 8 cutting teeth.

[0026] Embodiment 14, according to the rotary cutting tool with a serrated cutting edge described in Embodiment 1, it is characterized in that the chip groove of the tool body is a straight groove, and the angle between the cutting edge section on the cutting tooth and the tool body axis is greater than or equal to 0 degrees and less than or equal to 75 degrees, for example, greater than or equal to 8 degrees and less than or equal to 60 degrees, for example, greater than or equal to 10 degrees and less than or equal to 50 degrees, for example, greater than or equal to 20 degrees and less than or equal to 40 degrees, for example, greater than or equal to 30 degrees and less than or equal to 45 degrees. Optionally, the tool body has a taper.

[0027] Embodiment 15: A method for preparing a rotary cutting tool with a serrated cutting edge as described in any one of embodiments 1 to 14, characterized in that the chip breaker groove is prepared by a processing method that does not cause thermal damage.

[0028] Embodiment 16: The method according to embodiment 15 is characterized in that the chip breaker groove is prepared by a femtosecond pulse laser processing method.

[0029] Embodiment 17: A method for preparing a rotary cutting tool having a serrated cutting edge according to any one of embodiments 1 to 14, characterized in that it comprises the following steps:

[0030] The tool body chip groove is ground on the rotating cutting tool blank to form the tool body rake face.

[0031] A chip breaker groove is machined on the front cutting edge of the cutter body by using a femtosecond pulse laser, and a serrated cutting edge including a plurality of cutting teeth is formed.

[0032] The present invention proposes an innovative tool design and cutting strategy, which combines the advantages of right-hand spiral, left-hand spiral and straight groove milling cutters, and realizes the precise combination and intelligent control of cutting forces during the cutting process. Its beneficial technical effects include:

[0033] 1. The serrated edge design provided in the present application can not only effectively disperse the cutting force and significantly reduce the vibration of the tool, but also balance and control the axial cutting tension, axial cutting pressure and radial cutting force of the tool during the cutting process. This innovative design greatly improves the processing efficiency and processing accuracy, while significantly extending the service life of the tool. More importantly, it can also significantly reduce the deformation and vibration of thin-walled workpieces during the processing process, and improve the processing accuracy of thin-walled parts.

[0034] 2. The present application innovatively forms a serrated cutting edge by setting a chip breaker on the front face. This design can directly process a smooth surface without damaging the cutting edge and the back face. At the same time, the ingenious design of the chip breaker does not destroy the original chip removal channel on the front face, and can even set the chip guide surface in a directional manner as needed, thereby overcoming the unfavorable factor of the corrugated milling cutter in the prior art that the spiral surface is damaged by the swing of the grinding wheel when preparing the corrugated cutting edge. The chip removal effect is significantly improved, the accumulation of heat is avoided, the generation of built-up edge is reduced, and the surface finish of the workpiece is improved. In addition, the design of the chip breaker further increases the carrying space of the cutting fluid, which is conducive to the timely discharge of heat and provides a strong guarantee for an efficient and stable cutting process.

[0035] 3. The present invention forms a first rake angle through the groove surface of the chip breaker, thereby improving the sharpness of the edge along the extension direction of the serrated edge, reducing cutting resistance, and making cutting easier. The setting of the second rake angle can reduce chip friction, reduce heat accumulation, and make chips discharge smoothly.

[0036] 4. This application achieves the unique effect of unequal spacing and unequal division by adjusting the tooth pitch and / or tooth depth between the cutting teeth and staggering the cutting edges of different cutting teeth. This design further disperses the cutting force and effectively avoids the shaking and vibration of the tool during the cutting process, thereby significantly improving the service life of the tool. At the same time, this innovative design also greatly improves the surface finish of the product, providing a strong guarantee for high-precision processing.

[0037] 5. Through careful adjustment of the sawtooth edge shape, the tool of the present application innovatively sets a vertical edge segment on the spiral edge. This ingenious design enables the tool to have the dual advantages of a straight groove edge and a spiral groove edge, making the tool more vertical, reducing cutting resistance, and improving cutting accuracy. In addition, the tool of the present application also cleverly combines the left spiral and right spiral edges through the unique setting of the forward edge segment and the reverse edge segment, achieving effective dispersion of the cutting force, avoiding the concentration of cutting stress during the cutting process, and thus significantly improving the stability of the tool.

[0038] Through the improvements of this application, the service life of the tool has been greatly extended, and the cutting speed and processing efficiency have been significantly improved, thereby ensuring a stable and efficient cutting process. The chip breaker groove set on the front cutting edge forms a serrated edge. This design effectively improves the stability of the cutting edge, which not only further improves the cutting efficiency, but also significantly improves the cutting quality, ensuring that the workpiece surface achieves high finish and high precision. This innovative improvement provides a more reliable tool for precision machining and high-quality cutting of the workpiece surface, and especially successfully solves the industry problem of difficult-to-machine materials such as high-temperature alloy materials. In actual applications, the processing efficiency has been improved by more than 1.5 times, and the tool life has been increased by 1.5 to 3 times at the same time. In addition, the present application can also effectively reduce the deformation and vibration of thin-walled workpieces during the processing process, overcoming the technical bottleneck of the difficulty in processing thin-walled metals in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description only relate to some embodiments of the present disclosure, but are not intended to limit the present disclosure.

[0040] Figure 1 It is a structural schematic diagram of the milling cutter of Example 1;

[0041] Figure 2 A schematic diagram of a cutter body portion of a milling cutter according to Embodiment 1;

[0042] Figure 3 It is a partial schematic diagram of the chip breaker of the milling cutter of Example 1;

[0043] Figure 4 is a partial schematic diagram of the chip guiding surface of the milling cutter of Example 1;

[0044] Figure 5 Schematic diagram of a first rake angle and a second rake angle of the milling cutter of Example 1;

[0045] Figure 6 is a schematic diagram of the angle between the axis of the milling cutter and a point on the cutting edge in Example 1;

[0046] Figure 7 It is a partial enlarged view of the cutting edge of a cutting tooth when the milling cutter of Example 1 is placed vertically;

[0047] Figure 8 It is a schematic structural diagram of the milling cutter of Example 2;

[0048] Fig. 9 It is a schematic structural diagram of the cutter body of the milling cutter of Example 2;

[0049] Fig.10 It is a schematic diagram of the chip breaker and chip guide surface structure of the milling cutter of Example 2;

[0050] Fig.11 It is a partial enlarged view of the cutting edge of a cutting tooth when the milling cutter of Example 2 is placed vertically;

[0051] Fig.12 The expanded view of the serrated edge of Example 3;

[0052] Fig.13 for Fig.12 A partial enlarged view of the serrated edge;

[0053] Fig.14 is an expanded view of the serrated edge in Example 4;

[0054] Fig.15 for Fig.14 A partial enlarged view of the serrated edge;

[0055] Fig.16 is an expanded view of the serrated edge in Example 5;

[0056] Fig.17 for Fig.16 A partial enlarged view of the serrated edge;

[0057] Fig.18 It is a corrugated milling cutter in the prior art;

[0058] Fig.19 Schematic diagram of the rake face of the corrugated milling cutter;

[0059] Fig. 20 Schematic diagram of setting different lengths of forward edge segments and reverse edge segments for a serrated edge. Description of the drawings:

[0061] 100-tool body, 110-tool body chip groove, 120-cutting tooth, 130-tool body rake face, 140-chip breaker groove, 141-first rake angle face, 142-second rake angle face, 150-serrated cutting edge, 10-cutting tooth, 20-chip guiding surface, 11-forward cutting edge segment, 12-reverse cutting edge segment, 13-vertical cutting edge segment, 160-corrugated edge, 200-tool handle. DETAILED DESCRIPTION

[0062] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0063] The present application discloses a rotary cutting tool with a serrated cutting edge, comprising a tool body and an optional tool holder for direct or indirect connection with a machine tool, characterized in that the tool body is provided with a plurality of tool body chip grooves and cutting teeth corresponding to the tool body chip grooves, the surface of the tool body chip groove facing the cutting rotation direction is the tool body rake face, the tool body chip groove is a straight groove, and the tool body rake face includes a plane, or the tool body chip groove is a spiral groove, and the tool body rake face includes a spiral surface, and a chip breaker groove is provided on the tool body rake face, so that a serrated edge including a plurality of cutting teeth is formed on the cutting tooth The cutting edge, the serrated cutting edges of at least two or all of the cutting teeth on the same rotation center are located on the same cutting outer circle, the groove surface of the chip breaker groove extends in the width direction of the front cutting edge of the tool body to an area not exceeding two-thirds, one-half or one-quarter of the width of the front cutting edge of the tool body, or the groove surface of the chip breaker groove extends in the width direction of the front cutting edge of the tool body to an area more than two-thirds, one-half or one-quarter of the width of the front cutting edge of the tool body, and the groove surface of the chip breaker groove has a chip guiding surface, so that the chips can be guided into the chip groove of the tool body or the chips can be guided along the chip discharge direction of the chip groove of the tool body.

[0064] The present application forms a serrated cutting edge by arranging a chip breaker groove on the front cutting edge, which can not only effectively offset or balance the cutting forces from different directions (including axial cutting pressure, axial cutting tension and radial cutting force), thereby realizing the dual dispersion of cutting force and cutting heat, but also significantly improves the stability of the tool during the processing, reduces tool vibration, improves processing efficiency and processing accuracy, and increases tool life, thus opening up a new technical path for the processing of thin-walled metal parts.

[0065] In addition, the chip breaker groove provided on the front face of the present application does not damage the cutting edge, and a smooth surface can be directly processed on the workpiece. When the groove surface of the chip breaker groove extends to an area not exceeding two-thirds, one-half or one-quarter of the width of the front face of the cutter body in the width direction of the front face of the cutter body, the design of the chip breaker groove does not damage the original chip removal channel of the front face, and can achieve smooth chip removal. When the groove surface of the chip breaker groove extends to an area more than two-thirds, one-half or one-quarter of the width of the front face of the cutter body in the width direction of the front face of the cutter body, the chip guide surface is oriented to set the chip guide surface, so that the groove surface of the chip breaker groove has a chip guide function, and can effectively guide the chips into the chip groove of the cutter body, or smoothly discharge them along the chip removal direction of the chip groove of the cutter body. This overcomes the problem in the prior art that the corrugated milling cutter is not conducive to chip removal because the grinding wheel swings and destroys the spiral surface when preparing the corrugated cutting edge, avoids heat accumulation, reduces the generation of built-up edge, and improves the surface finish of the workpiece.

[0066] In some embodiments, the chip guiding surface is formed by a depression extending in the normal direction of the cutting edge or in the chip removal direction of the chip groove of the tool body, that is, the depression of the chip breaker groove extends in the normal direction of its corresponding cutting edge, or extends in the chip removal direction of the chip groove of the tool body. Optionally, the chip guiding surface also includes an arc transition surface between the bottom surface of the chip breaker groove and the front cutting edge of the tool body. Such a design helps to guide the discharge of chips more effectively. By directional setting of the chip guiding surface, the problem of the corrugated milling cutter in the prior art that the spiral surface is damaged by the swing of the grinding wheel when preparing the corrugated cutting edge, which is not conducive to chip removal, is overcome. The arc transition surface between the bottom surface of the chip breaker groove and the front cutting edge of the tool body can further achieve smooth chip removal, thereby avoiding heat accumulation. In addition, the chip breaker groove can further increase the cutting fluid carrying space, which is also conducive to the timely discharge of heat.

[0067] In some embodiments, the groove surface of the chip breaker has a first rake angle surface intersecting with the outer peripheral surface of the tool body, and the first rake angle surface forms a first rake angle on the serrated edge. The present application forms a first rake angle by forming the groove surface of the chip breaker, thereby improving the sharpness of the edge along the extension direction of the serrated edge, reducing cutting resistance, and making cutting easier.

[0068] In some embodiments, the width of the first front angle surface is 60%-140% of the feed per tooth. The applicant has found that the reasonable setting of the width of the first front angle surface can significantly improve the life of the tool, especially for the cutting of nickel-based alloys and titanium alloys. The reasonable proportional relationship between the width of the first front angle surface and the feed per tooth has a significant impact on the shape and size of the chips. The present application sets the first front angle surface to 60%-140% of the feed, preferably 60%-120%, which can increase the tool life by several times. For example, when the feed per tooth is 0.04mm, the width of the first front angle surface can be set between 0.024mm and 0.056mm, and when the feed per tooth is 0.04mm, the width of the first front angle surface can be set between 0.054mm and 0.126mm.

[0069] In some embodiments, the chip breaker groove is only provided at the depression of the serrated cutting edge, and the groove surface of the chip breaker groove intersects with the outer peripheral surface of the tool body and forms a first rake angle at the depression of the serrated cutting edge.

[0070] In some embodiments, the groove surface of the chip breaker has a second rake angle surface connected to the first rake angle surface to form a second rake angle, and the second rake angle is greater than the corresponding first rake angle. When the tool cuts the workpiece, the chips will curl and deform and generate friction with the tool and generate high temperature. By setting the second rake angle, the friction between the chips and the tool can be significantly reduced, and the heat accumulation and conduction can be reduced, which is convenient for the chips to be discharged more smoothly, and the generation of built-up edge can be reduced, and the surface finish of the workpiece can be improved. In particular, in the processing of nickel-based alloys, titanium alloys, steel, and stainless steel, the second rake angle surface can significantly reduce the accumulation of cutting heat and play a role in reducing the cutting temperature.

[0071] The terms in this application have the meanings commonly understood by those skilled in the art. For metal cutting tools, the angle between the rake face and the base surface is the rake angle. The "first rake angle" in this application refers to the angle between the groove surface (i.e., the first rake angle surface) of the chip breaker and the base surface in the measurement plane of the rake angle. The "second rake angle" in this application refers to the angle between the second rake angle surface and the base surface in the measurement plane of the rake angle.

[0072] For a selected point on a cutting edge without a chip breaker, it has a rake angle formed by the rake face. For a selected point on a cutting edge with a chip breaker, it has a first rake angle formed by the groove face of the chip breaker (i.e., the first rake face), or has a first rake angle and a second rake angle formed by the second rake face, in which case the first rake angle is the corresponding first rake angle of the second rake angle.

[0073] In some embodiments, the tooth pitch and / or tooth depth between the cutting teeth on the same cutting tooth are varied, that is, the wavelength and / or amplitude of the same cutting edge are different, so as to achieve the effect of unequal spacing and unequal division, further disperse the cutting force, avoid tool shaking and vibration, improve the stability of the cutting edge, reduce the deformation and vibration of thin-walled workpieces during processing, and ensure that the workpiece surface reaches high finish and high precision.

[0074] The "tooth pitch" in this application refers to the distance between adjacent crests of a serrated edge, or the distance between adjacent troughs, and the "tooth depth" refers to the height of the cutting tooth, that is, the vertical distance between the crest and the trough.

[0075] In some embodiments, the tooth pitch and / or tooth depth of the cutting teeth between adjacent cutting teeth have different changing rules, so that adjacent serrated edges are arranged in an interlaced manner. That is, the wavelength and / or amplitude between adjacent edges are different, achieving the effect of unequal distance and unequal division, so that the cutting force is further dispersed, the tool shaking and vibration are avoided, the stability of the edge is improved, the deformation and vibration of thin-walled workpieces during processing are reduced, and the workpiece surface is ensured to achieve high finish and high precision.

[0076] In some embodiments, the cutting teeth between adjacent cutting teeth do not overlap each other in the cutting rotation plane, so that adjacent serrated edges are arranged in an interlaced manner. That is, the starting points of adjacent serrated edges are different, achieving the effect of unequal distance and unequal division, so that the cutting force is further dispersed, the tool shaking and vibration are avoided, the stability of the cutting edge is improved, the deformation and vibration of thin-walled workpieces during the processing are reduced, and the workpiece surface is ensured to achieve high finish and high precision.

[0077] The core goal of the present invention is to solve the problem of workpiece deformation and tool deflection caused by excessive chip force in a single direction during the cutting process of thin-walled parts, thereby improving processing accuracy and workpiece verticality, and extending the service life of the tool. To achieve this goal, the present application adjusts the tooth pitch and / or tooth depth between the cutting teeth and staggers the cutting edges of different cutting teeth to achieve a unique layout of unequal spacing and unequal division. This design further disperses the cutting force and effectively avoids the flutter phenomenon of thin-walled parts, thereby significantly improving processing accuracy and improving the surface finish of the product.

[0078] In some embodiments, the pitch of the cutting teeth is 5% to 25% of the diameter of the cutter body.

[0079] In some embodiments, the tooth pitch of the cutting teeth is 2 mm to 5 mm, such as 2 mm to 3.5 mm. In some embodiments, the tooth depth of the cutting teeth is 0.2 mm to 1.5 mm, such as 0.5 mm to 1 mm.

[0080] In some embodiments, the angles between the cutting edges of different cutting teeth located in the same radial direction and the axis of the cutter body are different. That is, in the same radial direction, along the parallel to the axis of the cutter body, the angles between the tangents of the cutting edges of different cutting teeth and the axis of the cutter body are different. Such a setting can make the points on the cutting edges at any cutting moment have different force directions, thereby continuously dispersing the cutting force, avoiding tool shaking and vibration, and improving the stability of the tool during the processing process.

[0081] In some embodiments, the tool body chip groove is a spiral groove, at least some of the multiple cutting teeth of the serrated edge have a forward edge segment, the direction of the forward edge segment is the same as the spiral direction of the spiral groove, and at least some of the multiple cutting teeth of the serrated edge have a reverse edge segment, the direction of the reverse edge segment is opposite to the spiral direction of the spiral groove, and the angle between the reverse edge segment and the tool body axis is greater than or equal to 0 degrees and less than or equal to 75 degrees, such as greater than or equal to 8 degrees and less than or equal to 60 degrees, such as greater than or equal to 10 degrees and less than or equal to 50 degrees, such as greater than or equal to 20 degrees and less than or equal to 40 degrees, such as greater than or equal to 30 degrees and less than or equal to 45 degrees. The reverse spiral edge segment can form an opposite force at each cutting tooth, effectively offsetting or balancing the cutting forces in different directions (covering axial cutting pressure, axial cutting tension and radial cutting force), thereby achieving dual dispersion of cutting force and cutting heat, and increasing the stability of the tool.

[0082] In some embodiments, the tool body chip groove is a spiral groove, the helix angle is between 15 degrees and 35 degrees, and the rotary cutting tool has a constant helix angle, for example, the helix angle of the rotary cutting tool is 15 degrees, or 20 degrees, or 25 degrees, or 30 degrees, or 35 degrees. The multiple cutting teeth formed by the chip breaker groove of the present application can achieve different edge angles at a fixed chip groove helix angle, thereby achieving a combination of different edges.

[0083] In milling, left-hand spiral, right-hand spiral and straight groove milling cutters each have their own unique advantages and disadvantages for thin-walled parts processing. The advantages and disadvantages of these three types of milling cutters in thin-walled parts processing are as follows:

[0084] 1. Left-handed helical milling cutter, (a) Advantages: 1. Reduce vibration and deformation. When a left-handed helical milling cutter is cutting, the direction of the cutting force helps to reduce the vibration and deformation of the workpiece, which is especially suitable for the processing of thin-walled parts. The clockwise rotation cutting method can reduce the deformation and vibration of the material during the cutting process, thereby obtaining a better processing effect; 2. Improve processing accuracy: Since the left-handed helical milling cutter can effectively control the direction of the cutting force, reduce vibration and deformation, it can maintain a high processing accuracy when processing thin-walled parts; 3. Good cutting stability: The left-handed helical milling cutter has better stability during the cutting process, and can reduce the instability of the tool and workpiece caused by cutting force fluctuations. (b) Disadvantages: The feed speed is relatively slow. The feed speed of the left-handed helical milling cutter is relatively slow, and it may require a longer processing time. Therefore, in the pursuit of high-efficiency processing occasions, it is necessary to weigh its use.

[0085] 2. Right spiral milling cutter, (i) Advantages: 1. Fast processing speed: Right spiral milling cutter usually has a higher processing speed, which can greatly improve production efficiency and is suitable for processing occasions that pursue high efficiency. 2. Consistent cutting force direction: When the right spiral milling cutter is cutting, the direction of the cutting force is consistent with the direction of tool rotation, which helps to smooth the cutting process. (ii) Disadvantages: 1. High requirements for cutting force control: When processing thin-walled parts, special attention should be paid to the size and direction of the cutting force to avoid deformation of the workpiece caused by excessive cutting force or unreasonable direction. Therefore, the setting and control of cutting parameters are required to be high. 2. Surface problems may occur: When processing thin-walled parts, the right spiral milling cutter may generate vibration and cause deformation of the parts. At the same time, burrs and other problems are prone to appear on the processed surface, affecting the processing quality.

[0086] 3. Straight slot milling cutter, (i) Advantages: 1. Uniform distribution of cutting force: When cutting, the cutting force of the straight slot milling cutter is relatively uniform, which is conducive to maintaining the stability of the cutting process; 2. High processing efficiency: Under specific processing conditions, such as processing deep grooves and planes, the straight slot milling cutter has high processing efficiency. (ii) Disadvantages: 1. Insufficient control of the cutting force direction: The straight slot milling cutter may not be as effective as the spiral milling cutter in guiding the cutting force direction. When processing thin-walled parts, more attention should be paid to the setting and control of cutting parameters to prevent deformation of the workpiece caused by excessive cutting force or unreasonable distribution; 2. Limited processing accuracy: For thin-walled parts with high processing accuracy requirements, the straight slot milling cutter may be difficult to achieve the ideal processing effect because it is relatively weak in cutting force control and cutting stability.

[0087] It can be seen that different types of milling cutters have their own unique advantages. The design of a single tool in the prior art cannot integrate and give full play to the advantages of various types of tools. Limited by a single manufacturing method and grinding technology, the design potential of fusion cutting edge tools cannot be fully utilized. The present application innovatively realizes the serrated cutting edge design by cleverly combining left-spiral cutting edges, right-spiral cutting edges, straight groove cutting edges, and changing the spiral angle of the cutting edges. This unique combination can effectively disperse the axial cutting tension, axial cutting pressure, and radial chip force, greatly reducing the problem of workpiece deformation caused by excessively large chip force in a single direction on thin-walled parts.

[0088] In some embodiments, for any cutting tooth, the lengths of the forward cutting edge section and the reverse cutting edge section are not equal, so as to better balance or disperse the forces on the cutting edge and the tool, reduce tool vibration, and improve processing quality. Fig. 20As shown in the figure, a schematic diagram of setting different lengths of forward edge segments and reverse edge segments on a cutting tooth with a specific tooth depth on a spiral groove edge is shown. When the wave crest of the cutting tooth is at point C, the lengths of the forward edge segment AC and the reverse edge segment BC are substantially equal. When the wave crest of the cutting tooth moves down to point C2, the length of the forward edge segment AC2 is less than the length of the reverse edge segment BC2. When the wave crest of the cutting tooth moves up to point C1, the length of the forward edge segment AC1 is greater than the length of the reverse edge segment BC1. For different cutting conditions, by adjusting the ratio of the forward edge segment to the reverse edge segment, different force conditions of the cutting edge and the tool can be obtained, and reasonable adjustments and settings can be made for specific cutting conditions to offset or balance the cutting forces from different directions (covering axial cutting pressure, axial cutting tension and radial cutting force), and realize the precise combination and intelligent regulation of the cutting forces during the cutting process, thereby realizing the dual dispersion of cutting forces and cutting heat. That is, the cutting tool of the present application can adjust the angles of the cutting edges on both sides of the cutting teeth while keeping the tooth depth and / or tooth pitch unchanged to achieve a change in the serrated cutting edge, thereby precisely regulating the axial and radial cutting forces of the tool.

[0089] In some embodiments, the tool body chip groove is a spiral groove, and at least part of the plurality of cutting teeth of the serrated edge has a vertical edge segment, and the angle between the vertical edge segment and the tool body axis is less than 8 degrees, such as less than 5 degrees, such as less than 3 degrees, such as less than 2 degrees, such as 0 degrees. Such an arrangement can make the spiral edge include a straight groove edge segment, that is, a vertical edge segment, so that the tool has the advantages of both a straight groove and a spiral groove, and the transition edge segment between the vertical edge segments arranged in segmented intervals can further play a chip breaking role.

[0090] In some embodiments, the rotary cutting tool having a serrated cutting edge has 2 to 8 cutting teeth, such as 4 to 6 cutting teeth, such as 6 to 8 cutting teeth.

[0091] In some embodiments, the tool body chip groove is a straight groove, and the angle between the cutting edge section on the cutting tooth and the tool body axis is greater than or equal to 0 degrees and less than or equal to 75 degrees, for example, greater than or equal to 8 degrees and less than or equal to 60 degrees, for example, greater than or equal to 10 degrees and less than or equal to 50 degrees, for example, greater than or equal to 20 degrees and less than or equal to 40 degrees, for example, greater than or equal to 30 degrees and less than or equal to 45 degrees. Optionally, the tool body has a taper. Such a design allows the straight groove cutting edge to have the characteristics of a spiral cutting edge at the same time, so that the tool has the advantages of high verticality, low cutting resistance, and high cutting accuracy. For a straight groove milling cutter, the angle between its cutting edge and the tool body axis is 0 degrees. A straight groove milling cutter has the advantages of uniform cutting force distribution and high machining efficiency, but the straight groove milling cutter has insufficient control over the cutting force direction during cutting, resulting in limited machining accuracy. A serrated edge including multiple cutting teeth is formed by setting a chip breaker groove. For any cutting tooth, it includes two spiral edge segments in opposite directions. The lengths of the two spiral edge segments may be equal or unequal. At any point on the spiral edge segment, the angle between the tangent through the point and the axis of the tool body is the angle between the edge segment on the cutting tooth and the axis of the tool body. By setting the spiral edge segment, the line contact state of the straight groove edge during cutting is changed, and the cutting is performed using spiral edge segments with several cutting teeth respectively. The advantages of right-spiral, left-spiral and straight groove milling cutters are cleverly combined, and the verticality of the side wall can be improved in side wall processing, while the purpose of dispersing the cutting force and cutting heat is achieved, which significantly improves the stability of the tool during processing, and can also effectively reduce the temperature generated during cutting, extend the service life of the tool, and improve processing efficiency and precision.

[0092] The core purpose of the present invention is to reduce the vibration of thin-walled parts during the cutting process, thereby improving processing efficiency and processing accuracy, and extending the service life of the tool. Those skilled in the art understand that the force forms of left-handed spiral cutting edges, right-handed spiral cutting edges, and straight-groove cutting edges during cutting are significantly different, and different cutting edges have their own advantages and disadvantages. For example, the left-handed spiral cutting edge mainly produces axial pressure and radial cutting force during cutting, wherein the axial pressure presses the tool toward the fixture, and the right-handed spiral cutting edge mainly produces axial tension and radial cutting force during cutting, wherein the axial tension has a tendency to pull the tool out of the fixture, and the straight-groove cutting edge mainly produces radial cutting force. In order to better solve the influence of cutting force on the processing of thin-walled parts, it is necessary to balance the axial cutting tension, axial cutting pressure, and radial cutting force to reduce and disperse the cutting resistance, thereby improving the processing quality and efficiency. The serrated edge of the present application is achieved by combining a left spiral edge, a right spiral edge, a straight groove edge, and changes in the first rake angle, the second rake angle, and the angle of the edge. This combination can effectively disperse the axial cutting tension, axial cutting pressure, and radial cutting force, thereby significantly reducing the deformation of thin-walled parts caused by vibration. Furthermore, the present application achieves the unique effect of unequal spacing and unequal division by adjusting the tooth pitch and / or tooth depth between the cutting teeth and staggering the edges of different cutting teeth. This design further disperses the cutting force and effectively avoids the flutter phenomenon of thin-walled parts, thereby significantly improving the processing accuracy and the surface finish of the product, opening up a new technical path for the processing of thin-walled metal parts and has broad application prospects in the metal processing industry.

[0093] The present application also discloses a method for preparing the rotary cutting tool with a serrated cutting edge, characterized in that the chip breaker groove is prepared by a processing method that does not cause thermal damage.

[0094] In some embodiments, the chip breaker is prepared by a femtosecond pulse laser processing method.

[0095] In some embodiments, the method of the rotary cutting tool having a serrated cutting edge comprises the following steps:

[0096] The tool body chip groove is ground on the rotating cutting tool blank to form the tool body rake face.

[0097] A chip breaker groove is machined on the front cutting edge of the cutter body by using a femtosecond pulse laser, and a serrated cutting edge including a plurality of cutting teeth is formed.

[0098] The chip breaker described in the present application can be prepared by femtosecond pulse laser processing and forming, for example, a precision CNC laser machine purchased from DMG Mori Seiki Machine Tool Trading Co., Ltd. under the trade name LASERTEC 50Shape can be used. It is generally believed that laser processing and forming will deteriorate the performance of cemented carbide. For example, picosecond and nanosecond processing will cause thermal damage, forming a thermal damage layer at the chip breaker position, damaging the tool, and the surface finish is very poor. Not only can it not meet the finishing requirements, but the tool life is sharply reduced. Without being limited by theory, it is believed that the reason for the generation of this thermal damage layer is that the high temperature generated during the processing causes the cemented carbide to oxidize, the microstructure in the alloy changes, and the hardness and wear resistance are reduced. This can be clearly found by comparing the tool life with that without the thermal damage layer. The life of the tool with the thermal damage layer is often less than half of the tool without the thermal damage layer, and some even deteriorate to one-fifth of the normal life or even shorter. However, the use of femtosecond pulse laser processing will not cause thermal damage due to its extremely fast speed. Not only that, femtosecond pulse laser processing can also improve or enhance the performance of cemented carbide. Through this technology, we can create specific textures or microstructures on the surface of cemented carbide to achieve surface nano-crystallization. Using the high precision and control ability of femtosecond pulse lasers, we can create complex nano-scale structures on the surface of cemented carbide, thereby giving the material special properties, such as increased hardness, improved wear resistance, and increased fatigue life of the material. In addition, femtosecond pulse laser processing can also be used to repair microcracks or damage on cemented carbide tools, thereby further improving their surface properties. The surface finish after processing can reach 0.1-0.2nm, which is very suitable for fine processing.

[0099] The revolutionary design of the present application can not only effectively offset or balance the cutting forces from different directions (including axial cutting pressure, axial cutting tension and radial cutting force), realize the dual dispersion of cutting force and cutting heat, but also greatly improve the stability of the tool during the processing, while reducing the temperature generated during the cutting process, thereby extending the service life of the tool, and significantly improving the processing efficiency and precision, opening up a new technical path for the processing of thin-walled metal parts, and has broad application prospects in the metal processing industry.

[0100] The above ranges can be used alone or in combination. The present application can be more easily understood through the following examples.

[0101] Example

[0102] Example 1

[0103] like Figures 1 to 7As shown, this embodiment discloses a rotary cutting tool with a serrated edge, which is a milling cutter, including a cutter body 100 and a tool holder 200 for connecting to a machine tool, characterized in that the cutter body is provided with four cutter body chip grooves 110 and four cutting teeth 120 corresponding to the cutter body chip grooves, the surface of the cutter body chip groove facing the cutting rotation direction is the cutter body rake face 130, the cutter body chip groove is a spiral groove, and the cutter body rake face is a spiral surface,

[0104] A chip breaker groove 140 is provided on the front face of the cutter body, so that a serrated edge 150 including a plurality of cutting teeth 10 is formed on the cutting tooth 120, and the serrated edges of all the cutting teeth on the same rotation center are located on the same cutting outer circle.

[0105] The groove surface of the chip breaker groove extends to an area of ​​more than one quarter of the width of the front cutting edge of the cutter body in the width direction of the front cutting edge of the cutter body, Figure 3 A schematic diagram of the dimension is shown in the figure, in which line segment a marks the width of the chip breaker groove, that is, the dimension of the chip breaker groove in the direction perpendicular to the direction of the cutting edge, and line segment b marks the width of the front cutting edge of the tool body, that is, the dimension of the front cutting edge from the cutting edge to the bottom of the spiral groove in the direction perpendicular to the direction of the cutting edge. The dimension of a is approximately one-third of b, that is, the groove surface of the chip breaker groove extends in the width direction of the front cutting edge of the tool body to an area of ​​one-third of the width of the front cutting edge of the tool body, and the groove surface of the chip breaker groove has a chip guiding surface 20, so that the chips can be guided into the tool body chip groove or the chips can be guided along the chip removal direction of the tool body chip groove.

[0106] Figure 4 A schematic diagram of the chip guide surface 20 is shown in the figure, wherein the chip guide surface is formed by a depression extending in the normal direction of the cutting edge, which is the direction indicated by the two arrows pointing to the left in the figure. The arrow pointing upward indicated by the dotted line in the figure is the spiral direction of the spiral groove, which is also the chip discharge direction of the chips. The depressions of the two chip breaker grooves shown in the figure extend in the normal direction of the cutting edge of their corresponding cutting teeth 10, respectively. Such a setting can enable the chips to be discharged smoothly, and avoid the adverse effect of the chip breaker groove on the original chip removal channel caused by the front cutting edge. The problem of the corrugated milling cutter in the prior art being not conducive to chip removal because the spiral surface is damaged by the swing of the grinding wheel when preparing the corrugated cutting edge, thereby achieving smooth chip removal, reducing chip friction, avoiding heat accumulation, reducing the generation of built-up edge, and improving the surface finish of the workpiece. In addition, the chip breaker groove can further increase the cutting fluid carrying space, which is also conducive to the timely discharge of heat.

[0107] The groove surface of the chip breaker groove has a first rake angle surface intersecting with the outer peripheral surface of the tool body, and the first rake angle surface forms a first rake angle on the serrated edge. The groove surface of the chip breaker groove also has a second rake angle surface connected to the first rake angle surface to form a second rake angle, and the second rake angle is greater than the corresponding first rake angle. Figure 5 A schematic diagram of the first rake angle and the second rake angle is shown in FIG. Figure 5 Figure (a) is a schematic cross-sectional view perpendicular to the axis of the blade body at the recess of the serrated edge 150, and the cutting tooth 10 is shown in the dotted frame in the figure. Figure (b) is a partial enlarged view of the dotted frame in (a), and the dotted circle in the figure is the recess of the serrated edge, showing the first rake angle surface 141 and the second rake angle surface 142. Figure (c) is a partial enlarged schematic view of the area within the dotted circle in Figure (b) in the first rake angle measurement plane, in which the first rake angle α formed by the first rake angle surface 141 is 10 degrees, and the second rake angle β formed by the second rake angle surface 142 is 20 degrees. Figure 5 (c) also shows the width L of the first rake face 141, which is about 0.05 mm. During processing, the feed per tooth can be selected from 0.04 mm to 0.08 mm according to different processing conditions. The setting of the first rake angle and the second rake angle can reduce the cutting resistance, reduce the friction between the chips and the tool, make the chip removal smoother, make the cutting easier, and reduce the tool wear.

[0108] The pitch of the cutting teeth is 3 mm, which is the distance between two cutting teeth. Figure 3 The c marked in the figure shows the tooth distance.

[0109] The included angles between the cutting edges of different cutting teeth located in the same radial direction (in the same radial direction, parallel to the axial direction of the cutter body) (ie, the tangent of the cutting edges at that location) and the axis of the cutter body are different. Figure 6 Four dotted lines parallel to the axis of the tool body are shown in the figure, and each dotted line is in the same radial direction. For different cutting edge points on any of the dotted lines (i.e., the black points marked in the figure), the angle between the tangent of the cutting edge at that location and the marked dotted line is different. Therefore, during milling, the force directions of different cutting points and the workpiece in the same radial direction are slightly different at any time, thereby avoiding tool vibration.

[0110] Each cutting tooth 10 of the serrated edge has a forward edge segment 11 and a reverse edge segment 12, the direction of the forward edge segment 11 is the same as the spiral direction of the spiral groove, and the angle between the forward edge segment 11 and the axis of the tool body is greater than or equal to 0 degrees and less than or equal to 60 degrees, the direction of the reverse edge segment 12 is opposite to the spiral direction of the spiral groove, and the angle between the reverse edge segment 12 and the axis of the tool body is greater than or equal to 0 degrees and less than or equal to 45 degrees. Figure 7 The schematic diagram of the angle between the point d located on the positive cutting edge section 11 and the point e located on the reverse cutting edge section 12 and the axis of the cutter body is shown in FIG. The milling cutter is a right spiral milling cutter. Figure 7 Place the milling cutter vertically (with Figure 6The vertical dotted line in the figure is the axis of the tool body, which intersects with points d and e on the cutting edge. The figure also shows the tangents through points d and e, which form angles D and E with the axis of the tool body respectively. Angle D is 30 degrees, and angle E is 20 degrees. The directions of the two angles are different, so that the two cutting edges have different directions. The positive cutting edge segment 11 extends from left to right in the figure, which is the same as the spiral direction of the spiral groove, and the reverse cutting edge segment 12 extends from right to left in the figure, which is opposite to the spiral direction of the spiral groove.

[0111] This design allows the cutting edge to combine the characteristics of left-hand and right-hand spirals, while having the advantages of both left-hand and right-hand spiral edges. It can improve the verticality of the side wall during side wall processing, while achieving the purpose of dispersing the cutting force and cutting heat, significantly improving the stability of the tool during processing, and effectively reducing the temperature generated during the cutting process, thereby extending the tool life and improving processing efficiency and precision.

[0112] Example 2

[0113] like Figures 8 to 11 As shown, this embodiment discloses a rotary cutting tool with a serrated edge, which is a milling cutter, including a cutter body 100 and a tool holder 200 for being directly or indirectly connected to a machine tool, characterized in that the cutter body is provided with four cutter body chip grooves 110 and cutting teeth 120 corresponding to the cutter body chip grooves, and the surface of the cutter body chip groove facing the cutting rotation direction is the cutter body rake face 130,

[0114] The tool body chip groove 110 is a spiral groove, and the tool body rake face 130 is a spiral surface.

[0115] A chip breaker groove 140 is provided on the front cutting face 130 of the cutter body, so that a serrated edge 150 including a plurality of cutting teeth 10 is formed on the cutting tooth 120, and the serrated edges of all the cutting teeth on the same rotation center are located on the same cutting outer circle.

[0116] The groove surface of the chip breaker groove extends to an area of ​​about one-half of the width of the tool body front cutting edge in the width direction of the tool body front cutting edge, and the groove surface of the chip breaker groove has a chip guiding surface 20, so that the chips can be guided into the tool body chip groove or the chips can be guided along the chip discharge direction of the tool body chip groove.

[0117] The chip guiding surface 20 is formed by a depression extending toward the chip discharge direction of the tool body chip groove, that is, the depression of the chip breaker groove faces the chip discharge direction of the tool body chip groove. Fig.10The schematic diagram of the chip guide surface 20 is shown in FIG. The dotted arrow pointing to the upper right in the figure is the chip removal direction of the spiral groove. The groove surface of the chip breaker groove is provided with a depression between adjacent cutting teeth 10. The depression is marked with a short dotted arrow to indicate the extension direction of the depression, which extends toward the chip removal direction of the spiral groove. Such a setting can achieve smooth chip removal, reduce chip friction, avoid heat accumulation, reduce the generation of built-up edge, and improve the surface finish of the workpiece. In addition, the chip breaker groove can further increase the cutting fluid carrying space, which is also conducive to timely heat discharge.

[0118] The groove surface of the chip breaker groove has a first rake angle surface intersecting with the outer peripheral surface of the tool body, and the first rake angle surface forms a first rake angle on the serrated edge. The groove surface of the chip breaker groove also has a second rake angle surface connected to the first rake angle surface to form a second rake angle, and the second rake angle is greater than the corresponding first rake angle.

[0119] The tooth pitch of the cutting teeth is 3 mm.

[0120] The cutting teeth of the serrated edge have a vertical edge section 13, and the included angle between the vertical edge section 13 and the axis of the cutter body is less than 5 degrees and greater than 0 degrees. Fig.11 A schematic diagram of a vertical edge section 13 of one of the cutting teeth 10 is shown in FIG. Fig.11 Place the milling cutter vertically (with Fig. 9 The vertical dotted line in the figure is the axis of the cutter body, which intersects with point f on the cutting edge. The figure also shows the tangent through point f, which forms an angle F with the axis of the cutter body, and the angle F is 3 degrees. The cutting edge segment between the two vertical cutting edge segments 13 is a spiral cutting edge segment, which can play a chip breaking role in cutting, and such a setting can make the spiral cutting edge include a straight groove cutting edge segment, that is, a vertical cutting edge segment, integrating the dual advantages of right spiral and straight groove milling cutters. The transition cutting edge segment between the vertical cutting edge segments arranged in segmented intervals can further play a chip breaking role, so that the tool has the characteristics of high verticality, reduced cutting resistance, and high cutting accuracy. The tool life, cutting speed and processing efficiency are significantly improved, and a stable and efficient cutting process is ensured, which effectively reduces the deformation and vibration of thin-walled workpieces during processing.

[0121] Example 3

[0122] like Fig.12 and Fig.13 As shown, this embodiment discloses a rotary cutting tool with a serrated cutting edge, which is a milling cutter, comprising a cutter body and a cutter handle, characterized in that the cutter body is provided with four cutter body chip grooves and four cutting teeth corresponding to the cutter body chip grooves, and the surface of the cutter body chip groove facing the cutting rotation direction is the cutter body rake face,

[0123] The tool body chip groove is a spiral groove, and the tool body rake face is a spiral face,

[0124] A chip breaker groove is arranged on the front cutting face of the cutter body, so that a serrated edge including a plurality of cutting teeth is formed on the cutting teeth, and the serrated edges of all the cutting teeth on the same rotation center are located on the same cutting outer circle.

[0125] The groove surface of the chip breaker groove extends in the width direction of the rake face of the tool body to an area not exceeding one quarter of the width of the rake face of the tool body.

[0126] The groove surface of the chip breaker groove has a first rake angle surface intersecting with the outer peripheral surface of the tool body, and the first rake angle surface forms a first rake angle on the serrated edge. The groove surface of the chip breaker groove also has a second rake angle surface connected to the first rake angle surface to form a second rake angle, and the second rake angle is greater than the corresponding first rake angle.

[0127] The cutting teeth between adjacent cutting teeth do not overlap each other in the cutting rotation plane, so that the four serrated edges are arranged in an alternating manner. Fig.12 The expanded view of the serrated edge is shown in the figure, wherein the lines located in the upper part are the images of the four serrated edges after being expanded and projected onto the central axis of the tool body, and the three wavy lines located in the lower part are the images of the three serrated edges after being individually expanded and projected onto the central axis of the tool body, and the straight line in the figure is the central axis of the tool body. It can be seen from the figure that the ripples of different serrated edges have the same amplitude and wavelength, but the ripples do not overlap with each other, that is, the ripples have different starting points, so that the cutting teeth do not overlap with each other in the cutting rotation plane. Fig.13 Shows Fig.12 The four serrated edges at the top are expanded and projected onto the center axis of the cutter body (i.e. Fig.12 The enlarged part of the dotted box in the middle shows that the four serrated edges are arranged in an interlaced manner. This arrangement further disperses the cutting force, avoids the concentration of cutting stress during the cutting process, avoids tool shaking and vibration, improves the stability of the cutting edge, reduces the deformation and vibration of thin-walled workpieces during the processing, and ensures that the workpiece surface achieves high finish and high precision.

[0128] Example 4

[0129] like Fig.14 and Fig.15 As shown, this embodiment discloses a rotary cutting tool with a serrated edge, which is a milling cutter, including a cutter body and a cutter handle, characterized in that the cutter body is provided with four cutter body chip grooves and four cutting teeth corresponding to the cutter body chip grooves, and the surface of the cutter body chip groove facing the cutting rotation direction is the cutter body rake face,

[0130] The tool body chip groove is a spiral groove, and the tool body rake face is a spiral face,

[0131] A chip breaker groove is arranged on the front cutting face of the cutter body, so that a serrated edge including a plurality of cutting teeth is formed on the cutting teeth, and the serrated edges of all the cutting teeth on the same rotation center are located on the same cutting outer circle.

[0132] The groove surface of the chip breaker groove extends in the width direction of the rake face of the tool body to an area not exceeding one quarter of the width of the rake face of the tool body.

[0133] The groove surface of the chip breaker groove has a first rake angle surface intersecting with the outer peripheral surface of the tool body, and the first rake angle surface forms a first rake angle on the serrated edge. The groove surface of the chip breaker groove also has a second rake angle surface connected to the first rake angle surface to form a second rake angle, and the second rake angle is greater than the corresponding first rake angle.

[0134] The tooth pitch between the cutting teeth on the same cutting tooth is variable, and the tooth pitch between adjacent cutting teeth has different variation rules, so that the four serrated edges are arranged in an interlaced manner. Fig.14 The figure shows the unfolded view of the serrated edge, wherein the line located at the upper part is a view of the four serrated edges after unfolding and projecting onto the central axis of the blade body, and the three wavy lines located at the lower part are a view of the three serrated edges after each unfolding and projecting onto the central axis of the blade body, and the straight line in the figure is the central axis of the blade body. It can be seen from the figure that the ripples of different serrated edges have the same amplitude, but the wavelength of the ripples of the first serrated edge gradually decreases from left to right, that is, the tooth pitch of the cutting teeth gradually decreases, the wavelength of the second serrated edge gradually increases from left to right, that is, the tooth pitch of the cutting teeth gradually increases, the wavelength of the third serrated edge gradually decreases from left to right, and the wavelength of the fourth serrated edge gradually increases from left to right (not shown in the figure), and the first edge and the third edge, as well as the second edge and the fourth edge do not overlap with each other, and the crests and troughs of the ripples are intertwined, so that the four cutting teeth do not overlap with each other in the cutting rotation plane. Fig.15 Shows Fig.14 The four serrated edges at the top are expanded and projected onto the center axis of the cutter body (i.e. Fig.14 The area in the dotted box in the middle), as can be seen from the figure, the four serrated edges are arranged in an interlaced manner. This arrangement further disperses the cutting force, avoids the concentration of cutting stress during the cutting process, avoids tool shaking and vibration, improves the stability of the cutting edge, reduces the deformation and vibration of thin-walled workpieces during the processing process, and ensures that the workpiece surface achieves high finish and high precision.

[0135] Example 5

[0136] like Fig.16 and 17As shown, this embodiment discloses a rotary cutting tool with a serrated edge, which is a milling cutter, including a cutter body and a cutter handle, characterized in that the cutter body is provided with four cutter body chip grooves and four cutting teeth corresponding to the cutter body chip grooves, and the surface of the cutter body chip groove facing the cutting rotation direction is the cutter body rake face,

[0137] The tool body chip groove is a spiral groove, and the tool body rake face is a spiral face,

[0138] A chip breaker groove is arranged on the front cutting face of the cutter body, so that a serrated edge including a plurality of cutting teeth is formed on the cutting teeth, and the serrated edges of all the cutting teeth on the same rotation center are located on the same cutting outer circle.

[0139] The groove surface of the chip breaker groove extends in the width direction of the rake face of the tool body to an area not exceeding one quarter of the width of the rake face of the tool body.

[0140] The groove surface of the chip breaker groove has a first rake angle surface intersecting with the outer peripheral surface of the tool body, and the first rake angle surface forms a first rake angle on the serrated edge. The groove surface of the chip breaker groove also has a second rake angle surface connected to the first rake angle surface to form a second rake angle, and the second rake angle is greater than the corresponding first rake angle.

[0141] The tooth depths between the cutting teeth on the same cutting tooth vary, and the tooth depths of the cutting teeth between adjacent cutting teeth have different variation rules, so that the four serrated edges are arranged in an interlaced manner. Fig.16 The figure shows an example of an unfolded view of the serrated edge, wherein the line at the top is a view of the four serrated edges after unfolding and projecting onto the central axis of the cutter body, and the three wavy lines at the bottom are a view of the three serrated edges after each unfolding and projecting onto the central axis of the cutter body, and the straight line in the figure is the central axis of the cutter body. It can be seen from the figure that the ripples of different serrated edges have the same wavelength, but the amplitude of the ripples of the first serrated edge gradually decreases from left to right, that is, the tooth depth of the cutting teeth gradually decreases, and the amplitude of the ripples of the second serrated edge is It gradually increases from left to right, that is, the tooth depth of the cutting tooth gradually increases, the amplitude of the corrugation of the third serrated edge gradually decreases from left to right, and the amplitude of the corrugation of the fourth serrated edge gradually increases from left to right (not shown in the figure), and the first edge and the third edge, as well as the second edge and the fourth edge do not overlap with each other, the crests and troughs of the corrugations are staggered, and the amplitude of the corrugation of the second edge and the third edge is greater than that of the first edge and the fourth edge, so that the four cutting teeth do not overlap with each other in the cutting rotation plane. Fig.17 Shows Fig.16 The four serrated edges at the top are expanded and projected onto the center axis of the cutter body (i.e. Fig.16The area in the dotted box in the middle), as can be seen from the figure, the four serrated edges are arranged in an interlaced manner. This arrangement further disperses the cutting force, avoids the concentration of cutting stress during the cutting process, avoids tool shaking and vibration, improves the stability of the cutting edge, reduces the deformation and vibration of thin-walled workpieces during the processing process, and ensures that the workpiece surface achieves high finish and high precision.

[0142] Comparative Example 1

[0143] Fig.18 A corrugated milling cutter in the prior art is shown, which includes a cutter body 100 and a shank 200. The cutter body 100 is provided with a cutter body chip groove 110 and cutting teeth 120 corresponding to the cutter body chip groove. The cutter body chip groove is a spiral groove, and the surface of the cutter body chip groove facing the cutting rotation direction is the cutter body rake face 130. After the cutter body rake face is ground by a grinding wheel, the cutter body rake face intersects with the outer peripheral surface of the cutter body to form a corrugated edge 160.

[0144] Fig.19 The figure shows a depression extending to the bottom of the chip groove formed on the rake face corresponding to the edge of the concave portion of the corrugated blade 160 after grinding by a grinding wheel in the prior art, and the direction of the depression (i.e. the direction indicated by the three short arrows) is opposite to the chip removal direction of the chip groove (i.e. the direction indicated by the long arrow). The existence of the depression destroys the chip removal channel formed by the spiral surface, and the direction of the depression is opposite to the chip removal direction, which increases the chip removal resistance, making it difficult to remove the chips, thereby limiting the machining accuracy and life of the tool.

[0145] Comparative Example 2

[0146] This comparative example is a spiral groove end mill in the prior art, which has no chip breaker groove and no serrated edge, and the rest of the structure is consistent with Example 1.

[0147] The tool of the present application is prepared by the following method: a tool body chip groove is ground on a rotating cutting tool blank to form a tool body rake face, and a chip breaker groove is machined on the tool body rake face using a femtosecond pulse laser to form a serrated cutting edge including a plurality of cutting teeth, and a chip guide surface and a first rake angle surface and a second rake angle surface are machined at the same time.

[0148] Cutting test

[0149] The cutting tools of the embodiments and comparative examples of the present application were used to process thin-walled parts made of titanium alloy TC4. The machine equipment used was a DMG80 five-axis machine tool. The processing method was five-axis milling. The processing time, processing quantity, finish, and verticality (⊥) were measured. The processing test results are shown in Table 1 below:

[0150] Table 1

[0151]

[0152] Compared with the tool in the comparative example, the tool in the embodiment of the present application has significantly reduced vibration and noise during the processing, and the chip removal is smooth. It can be seen from the above-mentioned chip processing test results that the present application realizes the effective dispersion of axial cutting tension, axial cutting pressure and radial cutting force by combining a left spiral cutting edge, a right spiral cutting edge or a spiral cutting edge and a vertical cutting edge, and setting a first rake angle and a second rake angle, significantly reducing the deformation of thin-walled parts caused by vibration, thereby improving the processing stability. By optimizing the cutting edge design and the layout of the chip breaker, the generation of cutting heat and the concentration of cutting stress are reduced, and the wear or chipping of the cutting edge caused by local stress concentration is effectively avoided. At the same time, the design of the chip breaker significantly increases the chip capacity and chip removal space, which helps to discharge chips in a timely and smooth manner, further reduces the accumulation of cutting heat, and reduces the friction between chips and the tool. Therefore, the surface finish and verticality indicators of the workpiece after processing are significantly improved.

[0153] When processing thin-walled aviation parts with complex shapes, the technical solution of this application performs particularly well, significantly reducing tool wear and greatly extending the service life. At the same time, the cutting speed and processing efficiency are also significantly improved, ensuring the stability and efficiency of the cutting process. Overall, compared with the prior art, this application improves the processing efficiency by more than 1.5 times and increases the tool life by 1.5 to 3 times, showing significant superiority and application value.

[0154] The above description is merely an exemplary embodiment of the present disclosure and is not intended to limit the protection scope of the present disclosure. The protection scope of the present disclosure is determined by the appended claims.

Claims

1. A rotary cutting tool having a serrated cutting edge, comprising a tool body, and optionally a tool holder for direct or indirect connection with a machine tool, characterized in that: The cutter body is provided with a plurality of cutter body chip grooves and cutting teeth corresponding to the cutter body chip grooves. The surface of the cutter body chip groove facing the cutting rotation direction is the cutter body rake face. A chip breaker groove is arranged on the front cutting face of the cutter body, so that a serrated edge including a plurality of cutting teeth is formed on the cutting tooth, and the serrated edges of at least two or all the cutting teeth on the same rotation center are located on the same cutting outer circle, The groove surface of the chip breaker groove extends in the width direction of the front cutting edge of the tool body to an area not exceeding two-thirds, one-half or one-quarter of the width of the front cutting edge of the tool body. or, The groove surface of the chip breaker groove extends to an area of ​​two-thirds, one-half or more than one-quarter of the width of the front cutting edge of the tool body in the width direction of the front cutting edge of the tool body, and the groove surface of the chip breaker groove has a chip guiding surface, so that the chips can be guided into the chip groove of the tool body or the chips can be guided along the chip removal direction of the chip groove of the tool body.

2. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The chip guide surface is formed by a depression extending in the normal direction of the cutting edge or in the chip removal direction of the tool body chip groove, that is, the depression of the chip breaker groove extends in the normal direction of the corresponding cutting edge or in the chip removal direction of the tool body chip groove. Optionally, the chip guiding surface further includes an arc transition surface between the bottom surface of the chip breaker groove and the front cutting edge of the tool body.

3. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The groove surface of the chip breaker groove has a first rake angle surface intersecting with the outer peripheral surface of the tool body, and the first rake angle surface forms a first rake angle on the serrated cutting edge.

4. The rotary cutting tool with a serrated cutting edge according to claim 3, characterized in that: The chip breaker groove is only arranged at the concave part of the serrated cutting edge, and the groove surface of the chip breaker groove intersects with the outer peripheral surface of the tool body and forms a first front angle at the concave part of the serrated cutting edge.

5. The rotary cutting tool with a serrated cutting edge according to claim 3, characterized in that: The groove surface of the chip breaker groove has a second rake angle surface connected to the first rake angle surface to form a second rake angle, and the second rake angle is greater than the corresponding first rake angle.

6. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The tooth distance and / or tooth depth between the cutting teeth on the same cutting tooth varies.

7. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The tooth pitch and / or tooth depth of the cutting teeth between adjacent cutting teeth have different changing rules, so that the adjacent serrated cutting edges are arranged in a staggered manner.

8. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The cutting teeth between adjacent cutting teeth do not overlap each other in the cutting rotation plane, so that adjacent serrated edges are arranged in an interlaced manner.

9. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The tooth pitch of the cutting teeth is 5% to 25% of the diameter of the cutter body.

10. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The included angles between the cutting edges of different cutting teeth located in the same radial direction and the axis of the cutter body are different.

11. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The chip groove of the tool body is a spiral groove, and at least part of the plurality of cutting teeth of the serrated edge has a positive edge section, and the direction of the positive edge section is the same as the spiral direction of the spiral groove. Furthermore, at least part of the multiple cutting teeth of the serrated edge have a reverse edge segment, the direction of the reverse edge segment is opposite to the spiral direction of the spiral groove, and the angle between the reverse edge segment and the axis of the tool body is greater than or equal to 0 degree and less than or equal to 75 degrees, for example, greater than or equal to 8 degrees and less than or equal to 60 degrees, for example, greater than or equal to 10 degrees and less than or equal to 50 degrees, for example, greater than or equal to 20 degrees and less than or equal to 40 degrees, for example, greater than or equal to 30 degrees and less than or equal to 45 degrees.

12. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The chip groove of the tool body is a spiral groove, and at least part of the multiple cutting teeth of the serrated edge have a vertical edge segment, and the angle between the vertical edge segment and the tool body axis is less than 8 degrees, such as less than 5 degrees, such as less than 3 degrees, such as less than 2 degrees, such as 0 degree.

13. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The rotary cutting tool with a serrated cutting edge has 2 to 8 cutting teeth, such as 4 to 6 cutting teeth, such as 6 to 8 cutting teeth.

14. The rotary cutting tool with a serrated cutting edge according to claim 1, characterized in that: The chip groove of the tool body is a straight groove, and the angle between the cutting edge section on the cutting tooth and the tool body axis is greater than or equal to 0 degrees and less than or equal to 75 degrees, for example, greater than or equal to 8 degrees and less than or equal to 60 degrees, for example, greater than or equal to 10 degrees and less than or equal to 50 degrees, for example, greater than or equal to 20 degrees and less than or equal to 40 degrees, for example, greater than or equal to 30 degrees and less than or equal to 45 degrees. Optionally, the tool body has a taper.

15. A method for preparing a rotary cutting tool having a serrated cutting edge according to any one of claims 1 to 14, characterized in that: The chip breaker is prepared by a processing method that does not cause thermal damage.

16. The method according to claim 15, characterized in that The chip breaker is prepared by a femtosecond pulse laser processing method.

17. A method for preparing a rotary cutting tool having a serrated cutting edge according to any one of claims 1 to 14, characterized in that: It includes the following steps: The tool body chip groove is ground on the rotating cutting tool blank to form the tool body rake face. A chip breaker groove is machined on the front cutting edge of the cutter body by using a femtosecond pulse laser, and a serrated cutting edge including a plurality of cutting teeth is formed.

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