Positive rake angle bionic shell micro-groove self-lubricating cutting blade and preparation method thereof

Abstract

The invention is suitable for the technical field of cutting blades, and provides a positive rake angle bionic shell micro-groove self-lubricating cutting blade and a preparation method thereof.The positive rake angle bionic shell micro-groove self-lubricating cutting blade comprises a tool base body, the rake face of the tool base body is of a positive rake angle concave cambered surface structure, and a bionic shell micro-groove is formed in the concave cambered surface structure. The invention has the advantages of small cutting force, low cutting temperature, long service life, good processing quality and the like, and also has self-lubricating property.

Description

Technical Field

[0001] The invention belongs to the technical field of cutting blades, and in particular relates to a positive rake angle bionic shell micro-groove self-lubricating cutting blade and a preparation method thereof. Background Art

[0002] In machining, the performance of cutting inserts plays a critical role in both efficiency and quality. However, due to the material's physical and mechanical properties, these capabilities are limited. High cutting forces during the cutting process can lead to increased tool wear, particularly adhesive wear, which severely impacts product quality. Conventional cutting inserts often suffer from rapid tool wear and low precision when machining materials with high hardness and complex surface characteristics. Therefore, finding cutting inserts that improve production efficiency and reduce machining costs is a pressing issue.

[0003] Researchers have found that the surfaces of some animals are not completely smooth, but rather consist of tiny structural units arranged in a certain geometric pattern. However, these biological surfaces often have less friction. Biological structures show great potential in improving cutting performance and also provide a new research direction for optimizing tool performance.

[0004] Since the theory of friction reduction on non-smooth surfaces was proposed, the goal of extending tool life, reducing friction, and lowering cutting forces by texturing the tool surface has gained widespread attention in the manufacturing industry. Although tool surface texturing can alleviate the friction between the tool and the chip, under dry cutting conditions, the severe plastic deformation of the workpiece material and the high friction involved in the machining process will generate high temperatures, leading to higher wear rates. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide a positive rake angle bionic shell micro-groove self-lubricating cutting blade, aiming to solve the problems raised in the above background technology.

[0006] An embodiment of the present invention is implemented as follows: a self-lubricating cutting blade with a positive rake angle and bionic shell microgrooves comprises a tool base, the front cutting surface of the tool base is a concave arc structure with a positive rake angle, and the concave arc structure is provided with a bionic shell microgroove.

[0007] Preferably, the rake face is located in the tool tip cutting area.

[0008] Preferably, the bionic shell microgrooves are composed of a plurality of mutually parallel microgrooves, and the cross-sectional shape of the microgrooves is one of an arc shape, a triangle, and a trapezoid.

[0009] Preferably, the angle between the extension direction of the micro groove and the cutting speed direction is 0-45°.

[0010] Preferably, the micro grooves are filled with solid lubricant.

[0011] Preferably, the solid lubricant is a mixture of molybdenum disulfide and antimony trioxide, and the mass ratio of molybdenum disulfide to antimony trioxide is 1:1.

[0012] Another object of the present invention is to provide a method for preparing a positive rake angle bionic shell micro-groove self-lubricating cutting blade, comprising the following steps:

[0013] The tungsten carbide powder and the cobalt powder are mixed and placed in a blade mold, and pressed under high pressure and high temperature to prepare a tool matrix, and the tool matrix is cleaned and dried;

[0014] Laser processing equipment is used to process bionic shell micro grooves on the rake face of the tool substrate, and then cleaning is performed;

[0015] Solid lubricant powder is mixed with alcohol to form a suspension, and the suspension is filled into the bionic shell microgrooves by an immersion method, and then dried;

[0016] A TiAlN coating is deposited on the surface of the tool substrate by physical vapor deposition.

[0017] Preferably, the volume ratio of the tungsten carbide powder to the cobalt powder is 9:1; the pressure of the high pressure and high temperature is 1 MPa, and the temperature is 1500°C.

[0018] Preferably, the parameters of the laser processing equipment are: power 60%, pulse frequency f=30kHz, number of scans n=30 times, and scanning speed 3mm / s.

[0019] Preferably, the thickness of the TiAlN coating is 2 μm.

[0020] The embodiment of the present invention provides a positive rake angle bionic shell micro-groove self-lubricating cutting blade, which has the following advantages:

[0021] Small cutting force: Tools with positive rake face can effectively reduce the contact area and friction coefficient between the tool and the workpiece, thereby reducing cutting force and cutting power consumption;

[0022] Low cutting temperature: Bionic shell micro grooves can increase the heat dissipation area of the tool surface, promote heat exchange between the tool surface and the air, effectively reduce the cutting temperature and avoid heat accumulation;

[0023] Long tool life: The bionic shell micro-grooves can improve the wear resistance and anti-adhesion properties of the tool. The micro-grooves can capture tiny chips trapped on the tool surface and store them inside the tool, preventing the chips from being squeezed between the tool surface and the workpiece for a long time, causing abrasive wear and extending the tool life.

[0024] Good processing quality: Bionic shell micro grooves can effectively suppress the built-up edge generated during the cutting process and improve the processing surface quality;

[0025] Self-lubricating performance: The solid lubricant filled in the micro-grooves can be continuously released during the cutting process to form a lubricating film, continuously and stably supplying oil to the close contact area between the tool and the workpiece cutting layer, promoting chip removal and heat dissipation on the tool surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A flow chart of a method for preparing a positive rake angle bionic shell micro-groove self-lubricating cutting blade provided by an embodiment of the present invention;

[0027] Figure 2 A schematic structural diagram of a tool base with a rake face provided in an embodiment of the present invention;

[0028] Figure 3 A front view of a tool base body with a rake face provided by an embodiment of the present invention;

[0029] Figure 4 A schematic structural diagram of a positive rake angle bionic shell micro-groove self-lubricating cutting blade provided by an embodiment of the present invention;

[0030] Figure 5 A front view of a positive rake angle bionic shell micro-groove self-lubricating cutting blade provided by an embodiment of the present invention;

[0031] Figure 6 A side view of a positive rake angle bionic shell micro-groove self-lubricating cutting blade provided by an embodiment of the present invention;

[0032] Figure 7 A schematic diagram of the enlarged structure of the bionic shell micro-grooves in a positive rake angle bionic shell micro-grooves self-lubricating cutting blade provided by an embodiment of the present invention;

[0033] Figure 8 A schematic diagram of the operation of a positive rake angle bionic shell micro-groove self-lubricating cutting blade provided by an embodiment of the present invention.

[0034] In the accompanying drawings: 1- tool base; 2- rake face; 3- bionic shell micro groove. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] A positive rake angle bionic shell micro groove self-lubricating cutting blade, the preparation method of which is as follows Figure 1 As shown, the following steps are included:

[0037] Step 1: Preparation of a carbide tool substrate 1 with a rake face 2:

[0038] Tungsten carbide powder and cobalt powder are mixed in a volume ratio of 9:1, usually using a ball mill. Alcohol or other organic solvents are added during the ball milling process to prevent powder oxidation and improve mixing uniformity. The mixed powder is placed in a mold and pressed under high pressure to form a blade blank to form a dense cemented carbide structure. The sintered tool base 1 is post-processed to ensure that the tool base 1 has good precision and surface quality.

[0039] Step 2: Preparation of bionic shell microgrooves 3:

[0040] Since the perlite structure on the shell surface has good mechanical and tribological properties, the microstructure of the shell is introduced into the tool design through bionic design to form bionic shell microgrooves 3; Laser processing is a high-precision and high-efficiency micromachining method suitable for processing microgrooves on cemented carbide. The laser processing parameters are set as follows: power of 60%, pulse frequency f = 30 kHz, number of scans n = 30 times, scanning speed of 3 mm / s, the shape of the microgrooves is rectangular, and the cross-section shape can be circular arc, triangle or trapezoidal. The depth of the microgrooves is 10-50 μm, the width is 20-100 μm, the spacing between two adjacent microgrooves is 50-200 μm, and the angle between the arrangement direction of the microgrooves and the cutting speed direction is 0-45°. This arrangement can effectively guide the cutting fluid into the cutting area, improve the cooling effect, and at the same time reduce the contact area between the chips and the tool surface, thereby reducing the friction coefficient;

[0041] Step 3: Filling with solid lubricant:

[0042] Commonly used solid lubricants include molybdenum disulfide (MoS2), graphite, boron nitride (BN), etc., which have low friction coefficient, high wear resistance and good thermal stability, and are suitable for use under high temperature and high pressure cutting conditions. In order to prevent the oxidation of molybdenum disulfide during the cutting process, antimony trioxide is used as a flame retardant and is fully mixed with molybdenum disulfide in a volume ratio of 1:1 to ensure that molybdenum disulfide can continue to play a lubricating role. The impregnation method is suitable for powdered lubricants. The solid lubricant powder is mixed with alcohol to form a suspension. The suspension is filled into the microgrooves by impregnation and then dried at 80°C for 2 hours. The impregnation method can ensure that the lubricant is evenly distributed in the microgrooves and improve the lubrication effect.

[0043] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0044] like Figures 4 to 7FIG. 1 is a structural diagram of a positive rake angle bionic shell micro-groove self-lubricating cutting blade provided by one embodiment of the present invention, comprising:

[0045] The tool base body 1 comprises a front cutting surface 2 of the tool base body 1 which is a concave arc structure with a positive rake angle, and a bionic shell micro-groove is provided on the concave arc structure; the tool base body 1 is located in the tool tip cutting area.

[0046] In one embodiment of the present invention, the positive rake angle bionic shell micro groove self-lubricating cutting blade is provided with a tool base 1 with a rake face 2, such as Figures 2 to 3 As shown, the tool base 1 sets the rake face 2 in the tool tip area to a positive rake angle structure. Based on metal cutting theory, increasing the tool rake angle and reducing the tool wedge angle will reduce the contact radius of the tool tip arc with the workpiece cutting layer, further promoting the reduction of the friction coefficient. According to the shear theory of "the shear stress and the principal stress direction are 45 degrees", as the friction coefficient decreases and the shear angle increases, the cutting deformation decreases and the cutting force decreases.

[0047] In order to increase the strength of the tool more reasonably, the rake face 2 is designed to be a 5° arc surface concave from the starting point of the cutting tip to the inside, and the entire arc surface area is 5×5mm;

[0048] The material of the blade substrate 1 can be selected from cemented carbide, ceramic or superhard material;

[0049] Bionic shell micro groove 3 Figures 4 to 7 As shown in the figure, the rake face 2 with a positive rake angle is divided into two areas, namely the inner area RS and the outer area Rf. The RS area is a bionic shell micro-groove 3 structure embedded in the rake face 2. This area can serve as a storage container for lubricant and chips, and plays a role in spontaneously transporting chips during cutting; the Rf area is a 5° concave arc surface structure, which makes the cutting tool and the cutting layer of the workpiece non-tight contact, reducing the extrusion force of the tool on the cutting layer. The RS area and the Rf area work together to ensure the strength and impact resistance of the cutting part of the tool.

[0050] The RS region of the bionic shell microgroove 3 is composed of a plurality of rectangular microgrooves, the depth of the microgrooves is 10 to 50 μm, the width is 20 to 100 μm, the spacing between two adjacent microgrooves is 50 to 200 μm, the angle between the extension direction of the microgrooves and the cutting speed direction is 0 to 45°, and the cross-sectional shape of the microgrooves is arc-shaped, triangular or trapezoidal;

[0051] The self-lubricating blade works as Figure 8As shown, a solid lubricant is a solid substance used to reduce friction and wear between two sliding surfaces under load. In the embodiment of the present invention, antimony trioxide is selected as a flame retardant and molybdenum disulfide is selected as a lubricant, which are fully mixed in a volume ratio of 1:1 to prepare a positive rake angle self-lubricating cemented carbide blade to improve cutting performance.

[0052] In summary, the embodiment of the present invention promotes chip breaking and micro-groove storage through the positive rake face, and solid lubricant to improve the cutting performance of the tool, improve the efficiency of the tool, significantly reduce cutting heat and machine tool energy consumption, thereby meeting the needs of green processing of difficult-to-cut materials.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A positive rake angle bionic shell micro groove self-lubricating cutting blade, characterized in that: The tool comprises a tool base (1), wherein the front cutting surface (2) of the tool base (1) is a concave arc surface structure with a positive rake angle, and a bionic shell micro-groove (3) is provided on the concave arc surface structure.

2. The positive rake angle bionic shell micro groove self-lubricating cutting blade according to claim 1, characterized in that: The front cutting surface (2) is located in the cutting area of the cutting tip.

3. The positive rake angle bionic shell micro groove self-lubricating cutting blade according to claim 1, characterized in that: The bionic shell microgrooves (3) are composed of a plurality of mutually parallel microgrooves, and the cross-sectional shape of the microgrooves is one of an arc shape, a triangle shape, and a trapezoid shape.

4. The positive rake angle bionic shell micro groove self-lubricating cutting blade according to claim 1, characterized in that: The angle between the extension direction of the micro groove and the cutting speed direction is 0-45°.

5. The positive rake angle bionic shell micro groove self-lubricating cutting blade according to claim 1, characterized in that: The micro grooves are filled with solid lubricant.

6. The positive rake angle bionic shell micro groove self-lubricating cutting blade according to claim 5, characterized in that: The solid lubricant is a mixture of molybdenum disulfide and antimony trioxide, and the mass ratio of the molybdenum disulfide to antimony trioxide is 1:

1.

7. A method for preparing a positive rake angle bionic shell micro-groove self-lubricating cutting blade according to any one of claims 1 to 6, characterized in that: The following steps are involved: Mixing tungsten carbide powder and cobalt powder and placing them in a blade mold, pressing and molding them under high pressure and high temperature to prepare a tool base (1), and then cleaning and drying the tool base (1); Using laser processing equipment to process bionic shell micro grooves (3) on the rake face (2) of the tool base (1), and then cleaning; Mixing solid lubricant powder with alcohol to form a suspension, filling the suspension into the bionic shell microgrooves (3) by an immersion method, and then drying; A TiAlN coating is deposited on the surface of a tool substrate (1) by using a physical vapor deposition method.

8. The method for preparing the positive rake angle bionic shell micro-groove self-lubricating cutting blade according to claim 7, characterized in that: The volume ratio of the tungsten carbide powder to the cobalt powder is 9:1; the pressure of the high pressure and high temperature is 1 MPa, and the temperature is 1500°C.

9. The method for preparing the positive rake angle bionic shell micro-groove self-lubricating cutting blade according to claim 7, characterized in that: The parameters of the laser processing equipment are: power 60%, pulse frequency f=30 kHz, number of scans n=30 times, and scanning speed 3 mm / s.

10. The method for preparing the positive rake angle bionic shell micro-groove self-lubricating cutting blade according to claim 7, characterized in that: The thickness of the TiAlN coating is 2 μm.

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