Rotary cutting tool provided with multiple cooling grooves in flank and manufacturing method thereof

Abstract

The invention discloses a rotary cutting tool provided with a plurality of cooling grooves on a flank face, which is characterized in that each cutting edge is independently provided with a rake face, a flank face and a cutting edge, at least part of the cutting edge is provided with a plurality of cooling grooves on the flank face at intervals, and bulges are reserved between adjacent cooling grooves to form a plurality of reinforcing ribs; and the reinforcing ribs support the workpiece during cutting. Through the supporting effect of the reinforcing ribs on the workpiece, vibration of the workpiece is reduced, the cutter vibration phenomenon is restrained, impact of the workpiece on the cutting edge is reduced, the cutting edge is protected, tipping is reduced, the service life of the cutter is prolonged, meanwhile, dispersion of cutting force is achieved, and workpiece deformation caused by too large friction force and too high cutting temperature in the thin-wall workpiece machining process is reduced; and the method is particularly suitable for finish machining and thin-walled workpiece machining.

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 plurality of cooling grooves arranged on a back face thereof and a preparation method thereof. Background Art

[0002] During the milling process, the size of the back angle of the tool has an important influence on the friction between the back face and the transition surface layer and the edge strength. When the back angle decreases, the edge sharpness is poor, and the contact length between the workpiece and the back face of the tool will increase, which will increase the friction, thereby reducing the tool life and poor workpiece surface quality. When the back angle increases, the edge becomes sharper, the friction between the workpiece and the back face of the tool decreases, and the surface quality of the machined surface is better. However, when the back angle increases to a certain extent, the strength of the milling cutter cutting edge part is weakened, the heat dissipation conditions become worse, the tool wear rate is accelerated, and the tool life is reduced. The tool life and processing quality in the prior art are both poor, especially for thin-walled metal parts that are difficult to process. The cutting force and cutting heat can easily cause the workpiece to deform, and the tools in the prior art cannot meet the requirements of finishing and thin-walled parts processing accuracy and surface quality. Summary of the invention

[0003] The present invention provides a rotary cutting tool having a plurality of cooling grooves arranged on a back face, which includes the following embodiments:

[0004] Embodiment 1. A rotary cutting tool having a plurality of cooling grooves disposed on a back face, comprising a tool body, and an optional tool holder for direct or indirect connection with a machine tool, characterized in that:

[0005] The tool body has a plurality of cutting edges and a plurality of chip grooves corresponding to the cutting edges, each of the cutting edges independently has a rake face, a flank face and a cutting edge, and the chip grooves are spiral grooves.

[0006] At least part of the cutting edge has a plurality of cooling grooves starting from the cutting edge arranged at intervals on the back face and protrusions are left between adjacent cooling grooves to form a plurality of reinforcing ribs, which support the workpiece during cutting.

[0007] In the cutting rotation direction of the rotary cutting tool, the reinforcing ribs on adjacent cutting edges on which the reinforcing ribs are arranged are arranged alternately.

[0008] Embodiment 2. A rotary cutting tool having a plurality of cooling grooves arranged on the back cutting edge according to embodiment 1, characterized in that the cooling grooves arranged at intervals on the back cutting edge are at least partially interconnected to form a through groove extending along the cutting edge, and the reinforcing ribs are arranged at intervals in the groove.

[0009] Embodiment 3. A rotary cutting tool with multiple cooling grooves arranged on the back cutting edge as described in Embodiment 1, characterized in that at least part of the reinforcing ribs start at the cutting edge and have a first back angle surface close to the cutting edge or intersecting with the front cutting edge, so that the back cutting edge where the reinforcing ribs are arranged forms a first back angle at the corresponding cutting edge, and the cooling groove has a surface close to the cutting edge, which is a second back angle surface, which forms a second back angle at the corresponding cutting edge, and the second back angle is greater than the first back angle.

[0010] Embodiment 4. A rotary cutting tool having multiple cooling grooves arranged on the back cutting edge according to embodiment 3, characterized in that the first back angle is 5 to 8 degrees, the second back angle is 7 to 20 degrees, and the second back angle is greater than the first back angle by more than 1 degree, or more than 2 degrees.

[0011] Embodiment 5. A rotary cutting tool having a plurality of cooling grooves arranged on the back cutting surface according to embodiment 1, characterized in that the cooling grooves arranged at intervals on the back cutting surface include an area whose size gradually increases from close to the cutting edge to far from the cutting edge.

[0012] Embodiment 6. The rotary cutting tool having a plurality of cooling grooves arranged on the back face according to embodiment 1 is characterized in that the reinforcing ribs are arranged alternately with each other in the axial direction of the tool body.

[0013] Embodiment 7. A method for preparing the rotary cutting tool of any one of embodiments 1 to 6, comprising the steps of:

[0014] Outer contour processing step: according to the shape of the rotary cutting tool, processing the outer contour of the tool body, the chip groove, and the optional tool holder on the raw material;

[0015] Cooling groove and reinforcing rib processing steps: the cooling groove is formed by removing excess material on the back cutting surface, and protrusions are left between adjacent cooling grooves to form the reinforcing ribs.

[0016] Embodiment 8. The method according to embodiment 7 is characterized in that the reinforcing rib processing step is performed using a femtosecond pulse laser processing method.

[0017] Embodiment 9. A method for preparing the rotary cutting tool of embodiment 3 or 4, comprising the steps of:

[0018] Grinding a chip groove and a front cutting face on a rotary cutting tool blank, and grinding a back cutting face to form the first back angle face;

[0019] A femtosecond pulse laser processing method is adopted to remove excess material on the back tool surface to form the second back angle surface, and to form the reinforcing rib on the back tool surface.

[0020] The beneficial technical effects of the present invention include:

[0021] 1. The present application forms a variable back angle by arranging reinforcing ribs on the back tool face at intervals, or reduces the friction of the back tool face by reinforcing ribs when the back angle remains unchanged. This can increase the edge strength without significantly increasing the friction force, and reduce the vibration of the workpiece through the supporting effect of the reinforcing ribs on the workpiece, suppress the tool vibration phenomenon, reduce the impact of the workpiece on the cutting edge, protect the cutting edge, reduce chipping, extend the tool life, and achieve the dispersion of cutting force, reduce the deformation of the workpiece caused by excessive friction and high cutting temperature in the processing of thin-walled parts, and improve the surface quality of the workpiece. It is particularly suitable for fine processing and thin-walled parts processing.

[0022] 2. The present application forms a smaller first clearance angle and a larger second clearance angle at the cutting edge by setting reinforcing ribs at intervals, so that the tool has the advantages of both a large clearance angle and a small clearance angle. While ensuring high sharpness of the cutting edge and low cutting resistance, the tool still has high strength.

[0023] 3. The present application forms cooling grooves in areas where no reinforcing ribs are provided, thereby increasing the carrying space for the cutting fluid, providing better cooling and lubrication effects during the cutting process, reducing tool wear and thermal damage, and further improving tool life and processing quality.

[0024] The innovative design of this application provides a more reliable tool for precision machining and high-quality cutting of workpiece surfaces, greatly improving machining efficiency and machining 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 machining, improve the machining accuracy of thin-walled parts, and overcome the technical bottleneck of the difficulty in machining thin-walled metals in the prior art. In actual applications, the machining efficiency has been increased by more than 1.3 times, and the tool life has been increased by more than 1.6 times. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] 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 limitations of the present disclosure.

[0026] Figure 1 It is a structural schematic diagram of the milling cutter of Example 1;

[0027] Figure 2 It is a schematic diagram of the blade body in Example 1;

[0028] Figure 3 It is a partial enlarged view of the cooling groove and the reinforcing rib in Example 1;

[0029] Figure 4 is a schematic diagram of the blade body in Example 2;

[0030] Figure 5 It is a partial enlarged view of the cooling groove and the reinforcing rib in Example 2;

[0031] Figure 6 for Figure 4 AA section view in;

[0032] Figure 7 is an enlarged schematic diagram of the first back angle;

[0033] Figure 8 This is an enlarged schematic diagram of the second rear angle. Description of the drawings:

[0035] 100-tool body, 110-cutting edge, 120-chip groove, 130-front tool face, 140-cutting edge, 150-back tool face, 160-reinforcement rib, 10-first back angle face, 20-second back angle face, 30-cooling groove, 200-tool handle. DETAILED DESCRIPTION

[0036] 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.

[0037] The present application provides a rotary cutting tool with a plurality of cooling grooves arranged on the back 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 has a plurality of cutting edges and a plurality of chip grooves corresponding to the cutting edges, the cutting edges each independently having a front cutting edge, a back cutting edge and a cutting edge, the chip grooves being spiral grooves, at least part of the cutting edges having a plurality of cooling grooves starting from the cutting edge arranged at intervals on the back cutting edge and leaving protrusions between adjacent cooling grooves to form a plurality of reinforcing ribs, the reinforcing ribs providing support for the workpiece during cutting, and in the cutting rotation direction of the rotary cutting tool, the reinforcing ribs on adjacent cutting edges on which the reinforcing ribs are arranged are arranged alternately.

[0038] In milling, when the back angle is small, the tool sharpness is low, the friction area between the cutting edge and the workpiece increases, the greater the friction, the greater the cutting residual stress and the cutting hardening layer, resulting in an increase in cutting force and cutting temperature, which will not only accelerate the wear of the tool, but also may cause deformation and processing errors of the workpiece. Large friction area and cutting force may cause defects such as burrs and skew particles on the cutting surface, thereby reducing the accuracy and surface quality of parts. On the contrary, the larger the back angle, the smaller the contact area between the cutting edge and the workpiece surface, the sharper the tool, the smaller the friction, the smaller the cutting stress and the cutting hardening layer, and the smaller the cutting force not only reduces the wear of the tool, but also helps to reduce vibration and deformation during processing and improve processing accuracy. Increasing the back angle within an appropriate range can make the cutting surface smoother, reduce the generation of burrs and skew particles, and improve the accuracy and surface quality of parts. However, when the back angle is too large, the strength of the tool edge will be weakened, and it is easy to chip or break during the cutting process, reducing the durability and reliability of the tool. In addition, the too large back angle weakens the support of the workpiece during milling, which can easily lead to increased vibration during the cutting process, affecting the processing stability and accuracy, and in severe cases may even cause damage to the workpiece or machine tool failure. Especially in fine machining and thin-walled parts processing, due to the lack of support for the workpiece due to the large back angle, it is very easy to cause tool vibration, resulting in deformation of the workpiece and failure to meet processing requirements.

[0039] The present application arranges a plurality of reinforcing ribs at intervals on the back face of the rotating cutting tool, and the reinforcing ribs are used to form a variable back angle or to reduce the friction of the back face by the reinforcing ribs when the back angle remains unchanged, so that the edge strength can be increased without significantly increasing the friction force, and the reinforcing ribs have a good supporting effect, suppressing the vibration of the tool, and at the same time achieving the dispersion of the cutting force, reducing the deformation of the workpiece caused by excessive friction and excessive cutting temperature in the processing of thin-walled parts, and improving the surface quality of the workpiece processing, which is particularly suitable for fine processing and thin-walled parts processing. The back face of the tool and the area near the cutting edge in the area where the reinforcing ribs are set are thicker. This geometric shape enhances the strength and stability of the cutting edge, making it more able to withstand the cutting force during processing. Since the blade in this area is thicker, it is not easy to cause local chipping or excessive wear. The setting of the reinforcing ribs can not only improve the edge strength, but also provide support for the workpiece. Through the supporting effect of the reinforcing ribs on the workpiece, the impact of the workpiece vibration on the edge is reduced, the edge is protected, the chipping is reduced, and the tool life is extended.

[0040] In addition, by staggeredly arranging the reinforcing ribs on adjacent cutting edges, a hardened point is formed at the reinforcing rib of the preceding cutting edge, and the sharp edge of the following cutting edge at the cutting point can remove the hardened point on the workpiece.

[0041] The cooling grooves set in the present application start at the cutting edge, which means that the groove surface of the cooling groove intersects with the front cutting edge to form a cutting edge. In the area where the cooling groove is not set, the cutting edge is formed by the intersection of the front cutting edge and the back cutting edge or the surface of the reinforcing rib. The cooling grooves set at intervals on the back cutting edge can increase the carrying space of the cutting fluid on the back cutting edge and keep the cutting fluid in contact with the back cutting edge, thereby improving the cooling and lubrication effects.

[0042] In some embodiments, the cooling grooves arranged at intervals on the back tool face are at least partially interconnected to form a through groove extending along the cutting edge, and the reinforcing ribs are arranged at intervals in the grooves. The grooves extending along the cutting edge are arranged on the back tool face, and the reinforcing ribs are arranged at intervals in the grooves, which can further increase the cutting fluid carrying space. At the same time, the arrangement of the grooves can reduce the friction between the back tool face and the workpiece, and obtain a larger front angle along the cutting edge through the groove surface, thereby improving the sharpness of the cutting edge. The retained reinforcing ribs ensure that the tool does not change the supporting function and does not cause vibration.

[0043] In some embodiments, at least part of the reinforcing ribs starts at the cutting edge and has a first back angle surface close to the cutting edge or intersecting with the front cutting edge, so that the back cutting edge surface where the reinforcing ribs are provided forms a first back angle at the corresponding cutting edge, and the cooling groove has a surface close to the cutting edge, which is a second back angle surface, which forms a second back angle at the corresponding cutting edge, and the second back angle is greater than the first back angle.

[0044] The present application arranges reinforcing ribs and cooling grooves on the back tool surface at intervals to form a smaller first back angle and a larger second back angle respectively, so that the same cutting edge has the advantages of a large back angle and a small back angle, which can not only maintain a high sharpness and a small cutting resistance, but also increase the strength of the cutting edge without significantly increasing the friction through the arrangement of the reinforcing ribs. More importantly, the reinforcing ribs can support the workpiece during the cutting process and suppress the vibration of the tool. The arrangement of the cooling grooves increases the carrying space of the cutting fluid, provides better cooling and lubrication effects during the cutting process, reduces the wear and thermal damage of the tool, and further improves the tool life and processing quality.

[0045] In addition, due to the change in the sharpness of the same cutting edge, that is, the edge in the second back angle area is sharp and the cutting is light, while the edge sharpness in the first back angle area is lower, the cutting resistance increases locally and the local cutting temperature is high, making the metal hard and brittle, and the cutting amount in finishing is small, thus producing a certain chip breaking effect.

[0046] The terms in this application have the meanings commonly understood by those skilled in the art. For metal cutting tools, the angle between the back angle and the cutting plane is called the back angle. The "first back angle" in this application refers to the angle between the first back angle surface formed by the reinforcing ribs and the cutting plane at the cutting edge where the reinforcing ribs are provided, and the "second back angle" refers to the angle between the second back angle surface on the back angle surface and the cutting plane at the cutting edge where the reinforcing ribs are not provided.

[0047] In some embodiments, the first clearance angle is 5 to 8 degrees, the second clearance angle is 7 to 20 degrees, and the second clearance angle is greater than the first clearance angle by more than 1 degree, or more than 2 degrees, or more than 3 degrees, or more than 5 degrees, or more than 7 degrees. A smaller first clearance angle can improve the edge strength and provide support for the workpiece, reduce workpiece vibration, and reduce the impact of workpiece vibration on the edge. A larger second clearance angle can achieve better sharpness, and the smaller the cutting stress and the cutting hardened layer, the more the dispersion of cutting force can be achieved. Those skilled in the art can reasonably select the appropriate first clearance angle and second clearance angle based on factors such as processing materials and processing conditions. The difference between the first clearance angle and the second clearance angle is related to the tool diameter and the feed per tooth, and usually differs by more than 1 degree, or more than 2 degrees. The axial width of the first clearance angle surface can be selected according to actual conditions, and the minimum can be 0.02 mm.

[0048] In some embodiments, the cooling grooves arranged at intervals on the back tool face include areas whose size gradually increases from near the cutting edge to far from the cutting edge. A cooling groove of a larger size can be arranged far from the cutting edge without affecting the strength of the cutting edge, thereby increasing the carrying space of the cutting fluid on the back tool face. The areas whose size gradually increases from near the cutting edge to far from the cutting edge can keep the cutting fluid in contact with the back tool face continuously to avoid being thrown out, thereby increasing the carrying space and residence time of the cutting fluid, improving the cooling and lubrication effect, increasing the lubricity between the tool and the workpiece, and reducing the friction between the back tool face and the workpiece.

[0049] In some embodiments, the reinforcing ribs are arranged in an interlaced manner in the direction of the cutter body axis. The cutter body and the workpiece are milled in line contact in the direction of the cutter body axis, and the reinforcing ribs in the direction of the cutter body axis are arranged in an interlaced manner, so that the reinforcing ribs can continuously support the workpiece during the cutting process.

[0050] The present application proposes an innovative rotary cutting tool, which cleverly arranges multiple cooling grooves on the back face of the tool, and each cutting edge is independently and completely equipped with a front face, a back face and a sharp cutting edge. Multiple cooling grooves are arranged at intervals on the back face of at least part of the cutting edge, and a raised portion is retained between adjacent grooves, thereby naturally forming multiple reinforcing rib structures. These reinforcing ribs provide stable support for the workpiece during the cutting operation. Through the precise support of the reinforcing ribs, not only the friction resistance between the tool and the workpiece is significantly reduced, but also the vibration that may occur during the cutting process is effectively suppressed. At the same time, the design of the cooling groove achieves a dual improvement in the lubrication and cooling effects, greatly reduces the cutting temperature, further reduces the cutting residual stress and the thickness of the cutting hardened layer, and greatly reduces the impact of the workpiece on the cutting edge. This series of design measures not only effectively protects the integrity of the cutting edge, significantly reduces the risk of chipping, but also greatly extends the service life of the tool. In addition, the present application has successfully solved the problem of workpiece deformation caused by excessive friction resistance and high cutting temperature in thin-walled parts processing by dispersing the cutting force, thereby significantly improving the processing surface quality of the workpiece. The rotary cutting tool proposed in the present application is particularly suitable for fine machining and thin-walled parts processing fields with extremely high requirements on precision and surface quality.

[0051] On the other hand, the present application discloses a method for preparing the rotary cutting tool, which comprises the following steps:

[0052] Outer contour processing step: according to the shape of the rotary cutting tool, the outer contour of the tool body, the chip groove, and the optional tool handle are processed on the raw material;

[0053] Cooling groove and reinforcing rib processing steps: the cooling groove is formed by removing excess material on the back cutting surface, and protrusions are left between adjacent cooling grooves to form the reinforcing ribs.

[0054] Finally, the cutting tool is subjected to coating treatment, and the coating treatment is prepared by adopting a method of the prior art.

[0055] In some embodiments, the cooling groove and reinforcing rib processing steps are performed using a femtosecond pulse laser processing method.

[0056] The present application also discloses a method for preparing the rotary cutting tool, which comprises the following steps:

[0057] Grinding a chip groove and a front cutting face on a rotary cutting tool blank, and grinding a back cutting face to form the first back angle face;

[0058] A femtosecond pulse laser processing method is adopted to remove excess material on the back tool surface to form the second back angle surface, and to form the reinforcing rib on the back tool surface.

[0059] The reinforcing ribs 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.

[0060] The present application forms a variable back angle by setting reinforcing ribs at intervals, or reduces the friction of the back tool face by reinforcing ribs when the back angle remains unchanged. This can increase the edge strength without significantly increasing the friction, and has a good supporting effect, suppressing tool vibration, while achieving the dispersion of cutting force, reducing the deformation of workpieces caused by excessive friction and high cutting temperature during thin-walled part processing, and significantly improving processing efficiency and precision. The design of the cooling groove increases the carrying space of the cutting fluid, provides better cooling and lubrication effects during the cutting process, reduces tool wear and thermal damage, and further improves tool life and processing quality, opening up a new technical path for the processing of thin-walled metal parts, and has broad application prospects in the metal processing industry.

[0061] The above ranges can be used alone or in combination. The present application can be more easily understood through the following examples.

[0062] Example

[0063] Example 1

[0064] like Figures 1 to 3 As shown, this embodiment discloses a rotary cutting tool with a plurality of cooling grooves and reinforcing ribs arranged on the back face, which is an end mill, comprising a cutter body 100 and a tool holder 200 for connecting to a machine tool, wherein the cutter body has four cutting edges 110 and four chip grooves 120 corresponding to the cutting edges, Figure 2 It is a schematic diagram of a tool body, wherein the cutting edges independently have a rake face 130, a flank face 150 and a cutting edge 140, and the chip groove is a spiral groove with a spiral angle of 40 degrees.

[0065] The cutting edge is provided with a plurality of cooling grooves 30 starting from the cutting edge at intervals on the back face of the cutting edge and protrusions are left between adjacent cooling grooves to form a plurality of reinforcing ribs 160, and the reinforcing ribs 160 support the workpiece during cutting. Figure 3A partial enlarged view of the cooling groove 30 and the reinforcing rib 160 is shown. The adjacent cooling grooves 30 are interconnected to form a through groove extending along the cutting edge 140. The groove surface of the cooling groove intersects with the front cutting edge to form the cutting edge 140. The reinforcing rib 160 is arranged in the groove at intervals. The starting point of the protrusion is located in the groove (that is, the starting point of the protrusion is a certain distance from the cutting edge 140). The through groove makes the tool have a back angle of about 15 degrees. The through groove increases the carrying space of the cutting fluid, provides better cooling and lubrication effects during the cutting process, reduces the wear and thermal damage of the tool, and further improves the tool life and processing quality.

[0066] In the cutting rotation direction of the rotary cutting tool, the reinforcing ribs on adjacent cutting edges are arranged in a staggered manner. In the direction of the tool body axis, the reinforcing ribs are arranged in a staggered manner.

[0067] By setting reinforcing ribs at intervals on the back tool face, the friction of the back tool face can be reduced by the reinforcing ribs without changing the back angle. This can increase the edge strength without significantly increasing the friction. The supporting effect of the reinforcing ribs on the workpiece can reduce the vibration of the workpiece, suppress the tool vibration, reduce the impact of the workpiece on the cutting edge, protect the cutting edge, reduce edge chipping, extend the tool life, and disperse the cutting force, reduce the deformation of the workpiece caused by excessive friction and high cutting temperature in the processing of thin-walled parts, and improve the surface quality of the workpiece. It is especially suitable for fine processing and thin-walled parts processing.

[0068] The tool was prepared as follows:

[0069] Outer contour processing step: according to the shape of the rotary cutting tool, the outer contour of the tool body, the chip groove, and the tool handle are processed on the raw material;

[0070] The cooling groove and reinforcing rib processing step is to remove excess material on the back face, set a through groove extending along the cutting edge on the back face, and leave protrusions between the grooves to form the cooling groove and reinforcing rib. The cooling groove and reinforcing rib processing step is performed by a femtosecond pulse laser processing method.

[0071] Example 2

[0072] like Figures 4 to 8 As shown, this embodiment discloses a rotary cutting tool with multiple cooling grooves and reinforcing ribs arranged on the back face, which is an end mill, and its structure is basically the same as that of Example 1, including a tool body 100, and a tool holder for connecting to a machine tool, characterized in that the tool body has four cutting edges 110 and four chip grooves 120 corresponding to the cutting edges, and the cutting edges each independently have a front face 130, a back face 150 and a cutting edge 140, and the chip groove is a spiral groove with a spiral angle of 40 degrees.

[0073] The cutting edge has a plurality of cooling grooves 30 arranged at intervals on the back face starting from the cutting edge and protrusions are left between adjacent cooling grooves to form a plurality of reinforcing ribs 160, the reinforcing ribs 160 support the workpiece during cutting, and the reinforcing ribs on adjacent cutting edges are arranged in an interlaced manner in the cutting rotation direction of the rotary cutting tool. In the direction of the tool body axis, the reinforcing ribs are arranged in an interlaced manner.

[0074] Figure 5 A partial enlarged view of the cooling groove 30 and the reinforcing rib 160 is shown. The size of the cooling groove gradually increases from the edge to the edge, so that the cutting fluid can keep in contact with the back face to avoid being thrown out, increase the cutting fluid carrying space and residence time, improve the cooling and lubrication effect, increase the lubricity between the tool and the workpiece, and reduce the friction between the back face and the workpiece. The reinforcing rib 160 starts at the edge 140 and has a first back angle surface 10 intersecting with the front face 130, so that the back face where the reinforcing rib is set forms a first back angle at the corresponding edge. The cooling groove 30 has a groove surface near the edge, which is a second back angle surface 20. The second back angle surface 20 forms a second back angle at the corresponding edge, and the second back angle is greater than the first back angle. Figures 6 to 8 A schematic diagram of the first back angle and the second back angle is shown, wherein Figure 6 for Figure 4 In the AA section view in the figure, in the AA section, the cutting edge at point a is provided with a reinforcing rib on the back face, and the cutting edge at point b adjacent to the cutting edge is provided with a cooling groove, so that Figure 6 In the figure, the edge pointed by point a has the first back angle, and the edge pointed by point b has the second back angle. Figure 7 for Figure 6 An enlarged schematic diagram of the first back angle at point a. Figure 8 for Figure 6 An enlarged schematic diagram of the second back angle at point b. Figure 7 The first back angle α is about 8 degrees, Figure 8 The second back angle β is about 15 degrees.

[0075] The cutting edge of the tool is formed by the intersection of the groove surface of the cooling groove and the reinforcing rib (i.e., the back tool face) with the front tool face, and a variable back angle is formed by the cooling groove and the reinforcing rib, so that the same cutting edge has the advantages of a large back angle and a small back angle, which can not only maintain a high sharpness and a small cutting resistance, but also increase the strength of the cutting edge without significantly increasing the friction through the setting of the reinforcing ribs. The reinforcing ribs have a good supporting effect, suppress tool vibration, and at the same time achieve the dispersion of cutting force, reduce the deformation of the workpiece caused by excessive friction and high cutting temperature in the processing of thin-walled parts, and improve the surface quality of the workpiece. It is especially suitable for fine machining and thin-walled parts processing.

[0076] The tool was prepared as follows:

[0077] Grinding a chip groove and a front cutting face on a rotary cutting tool blank, and grinding a back cutting face to form the first back angle face;

[0078] A femtosecond pulse laser processing method is used to remove excess material on the back tool surface, and cooling grooves are arranged on the back tool surface at intervals and protrusions are left between the cooling grooves to form reinforcing ribs, and the groove surface of the cooling groove close to the cutting edge forms the second back angle surface.

[0079] The cutting tools in the embodiments of the present application are all coated.

[0080] Cutting test

[0081] The tool of the embodiment of the present application was 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 finishing. The processing time, processing quantity, finish, and verticality (⊥) were measured. The tool of the comparative example did not have cooling groove reinforcement ribs on the back face.

[0082] The processing test results are shown in Table 1 below:

[0083] Table 1

[0084]

[0085]

[0086] When machining thin-walled parts, the verticality and smoothness of the cutting tool of the embodiment of the present application are significantly better than those of the control example, and the tool life and machining efficiency are significantly improved, indicating that the support of the workpiece by the reinforcing ribs can suppress the vibration of the tool, reduce the impact of the workpiece on the cutting edge, protect the cutting edge, reduce the chipping of the cutting edge, and extend the tool life. It can also provide better cooling and lubrication effects during the cutting process, reduce the deformation of the workpiece caused by excessive friction and high cutting temperature in the machining of thin-walled parts, and improve the surface quality of the workpiece machining, which is especially suitable for finishing and thin-walled parts machining. In this application, the tool life is increased by 1.6 to 2 times while the machining efficiency is increased by more than 1.3 times, showing significant superiority and application value.

[0087] 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 plurality of cooling grooves arranged on the back face of the cutting tool, comprising a cutting body and an optional tool holder for direct or indirect connection with a machine tool, characterized in that: The tool body has a plurality of cutting edges and a plurality of chip grooves corresponding to the cutting edges, each of the cutting edges independently has a rake face, a flank face and a cutting edge, and the chip grooves are spiral grooves. At least part of the cutting edge has a plurality of cooling grooves starting from the cutting edge arranged at intervals on the back face and protrusions are left between adjacent cooling grooves to form a plurality of reinforcing ribs, which support the workpiece during cutting. In the cutting rotation direction of the rotary cutting tool, the reinforcing ribs on adjacent cutting edges on which the reinforcing ribs are arranged are arranged alternately.

2. The rotary cutting tool having a plurality of cooling grooves provided on the back face according to claim 1, characterized in that: The cooling grooves arranged at intervals on the back cutting surface are at least partially interconnected, so as to form a through groove extending along the cutting edge, and the reinforcing ribs are arranged at intervals in the groove.

3. The rotary cutting tool having a plurality of cooling grooves provided on the back face according to claim 1, characterized in that: At least part of the reinforcing ribs starts at the cutting edge and has a first back angle surface close to the cutting edge or intersecting with the front cutting edge, so that the back cutting edge where the reinforcing ribs are set forms a first back angle at the corresponding cutting edge, and the cooling groove has a surface close to the cutting edge, which is a second back angle surface, which forms a second back angle at the corresponding cutting edge, and the second back angle is greater than the first back angle.

4. The rotary cutting tool having a plurality of cooling grooves provided on the back face according to claim 3, characterized in that: The first clearance angle is 5 to 8 degrees, the second clearance angle is 7 to 20 degrees, and the second clearance angle is greater than the first clearance angle by 1 degree or more, or by 2 degrees or more.

5. The rotary cutting tool having a plurality of cooling grooves provided on the back face according to claim 1, characterized in that: The cooling grooves arranged at intervals on the back face include areas with gradually increasing sizes from near the cutting edge to far away from the cutting edge.

6. The rotary cutting tool having a plurality of cooling grooves provided on the back face according to claim 1, characterized in that: In the axial direction of the cutter body, the reinforcing ribs are arranged alternately.

7. A method for preparing a rotary cutting tool according to any one of claims 1 to 6, comprising the steps of: Outer contour processing step: according to the shape of the rotary cutting tool, the outer contour of the tool body, the chip groove, and the optional tool handle are processed on the raw material; Cooling groove and reinforcing rib processing steps: the cooling groove is formed by removing excess material on the back cutting surface, and protrusions are left between adjacent cooling grooves to form the reinforcing ribs.

8. The method according to claim 7, characterized in that The cooling groove and reinforcing rib processing steps are performed using a femtosecond pulse laser processing method.

9. A method for preparing a rotary cutting tool according to claim 3 or 4, comprising the steps of: Grinding a chip groove and a front cutting face on a rotary cutting tool blank, and grinding a back cutting face to form the first back angle face; A femtosecond pulse laser processing method is adopted to remove excess material on the back tool surface to form the second back angle surface, and to form the reinforcing rib on the back tool surface.

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