Stainless steel cutting tool

Abstract

The invention provides a stainless steel cutting tool which comprises a tool body, one end of the tool body is a clamping part, the other end of the tool body is a cutting part for cutting a workpiece, the cutting part is formed by spirally extending four racks along the central axis of the tool body, a tool groove is formed between every two adjacent racks, and the top end of each rack is provided with an end edge; a chip containing groove for discharging cuttings is formed between every two adjacent end edges; the radial angles of the adjacent racks are different and are 95 degrees + / -1 degrees or 85 degrees + / -1 degrees, and the sum of the two adjacent radial angles is 180 degrees. According to the invention, the rack adopts unequal spiral design, so that the resonance phenomenon can be reduced; the design of the four-rack circumferential blade and the U-shaped cutter groove is adopted, the overall stress of the cutter is more uniform when stainless steel is machined, the sharpness and durability of the cutting edge of the circumferential blade of the cutter are improved through the improved design of the circumferential blade structure, the cutting process is easier and smoother, and therefore the durability of the cutter is improved.

Description

Technical Field

[0001] This invention discloses a stainless steel cutting tool, which belongs to the category of machining supplies. Background Technology

[0002] Stainless steel is characterized by its high strength and toughness, work hardening during cutting, large cutting forces, and tendency to stick to the cutting tool at high cutting temperatures. This can easily lead to tool chipping and sticking during roughing, resulting in overall tool failure and reduced tool life.

[0003] To address the cutting characteristics of stainless steel, the tool design and manufacturing primarily utilize high-strength, high-toughness materials, coupled with a wear-resistant coating. Furthermore, the cutting edge is structurally strengthened, and the serrations on the cutting edge are microscopically controlled. The entire tool undergoes high-level polishing and post-coating polishing. The drawbacks of this method are that high-level polishing requires the use of extremely fine, specialized grinding wheels, and controlling the serrations on the cutting edge necessitates optimization of machining parameters and strict control of the machining environment (temperature and humidity).

[0004] Therefore, it is necessary to propose a stainless steel cutting tool to improve its service life. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the main purpose of this invention is to overcome the disadvantages of the tool being short-lived and easily worn in the roughing process of stainless steel, and to improve the tool service life.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A stainless steel cutting tool includes a tool body, one end of which is a clamping part, and the other end is a cutting part for cutting the workpiece. The cutting part is formed by four racks extending spirally along the central axis of the tool body. A groove is formed between adjacent racks, and an end cutting edge is provided at the top of each rack. A chip-removing groove is provided between every two adjacent end cutting edges. The radial angles of adjacent racks are different.

[0008] Furthermore, the radial angle between adjacent racks is 95°±1° or 85°±1°, and the sum of two adjacent radial angles is 180°.

[0009] Furthermore, the rack includes two long teeth and two short teeth arranged opposite to each other, wherein the two long teeth correspond to the end cutting edge passing through the central axis of the cutter body, and the distance between the tips of the two long teeth and the end cutting edge is 0.2-0.25cm, and the cutting edge inclination angle is 1.5°±0.2°.

[0010] Furthermore, the end blade includes a rearwardly inclined first front end face, a second front end face disposed behind the first front end face, and a first lower end face disposed below the first front end face, wherein the first front end face, the second front end face, and the first lower end face are all planar.

[0011] Furthermore, the front angle of the cutting edge is 4°±0.5°, the first rear angle of the cutting edge is 10°±0.2°, and the second rear angle of the cutting edge is 22°±0.4°.

[0012] Furthermore, the cutting groove is U-shaped.

[0013] Furthermore, the rack is provided with a peripheral blade, which includes a rearwardly inclined third front end face, a fourth front end face disposed behind the third front end face, and a second lower end face disposed below the third front end face. The third front end face and the second lower end face are arc surfaces, and the fourth front end face is a plane.

[0014] Furthermore, the rake angle of the circumferential cutting edge is 5°±1°, the first rear angle of the circumferential cutting edge is 10°±1°, and the second rear angle of the circumferential cutting edge is 28°±2°.

[0015] Furthermore, the cutting groove includes a long tooth cutting groove and a short tooth cutting groove. The long tooth cutting groove is a straight cutting groove with a tooth clearance angle of 35°±0.2°. The short tooth cutting groove is an arc cutting groove with a tooth clearance angle of 40°±0.2° and a tooth clearance rake angle of 4°±0.4°.

[0016] Furthermore, the helix angle of the rack is 40°±1°.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects:

[0018] Due to the mechanical properties of stainless steel, vibration and chip adhesion occur during machining. Microscopically, vibration causes the cutting edge to strike the material surface, while chip adhesion leads to a blunting of the cutting edge, an increased rake angle, and even a negative rake angle, further increasing cutting resistance and friction, accelerating tool failure. Setting the four racks in an unequal-division helix reduces resonance; the U-shaped flute ensures more even stress distribution across the tool during machining, reducing stress concentration. By designing the angle and shape of the rake angle of the peripheral cutting edge, the sharpness and durability of the peripheral cutting edge are improved, resulting in a smoother and easier cutting process, thus enhancing tool durability. Attached Figure Description

[0019] Figure 1 This is a front view of the blade.

[0020] Figure 2 for Figure 1 A schematic diagram of part A in the middle.

[0021] Figure 3 This is a schematic diagram of the cross-section of the cutting part.

[0022] Figure 4 This is a schematic diagram of Zhou Ren.

[0023] Figure 5 This is a schematic diagram of the backlash angle of the cut groove.

[0024] Figure 6 This is a schematic diagram of the cutting edge in direct view.

[0025] Figure 7 for Figure 6 A schematic diagram of part B in the middle.

[0026] Figure 8 This is a schematic diagram of a cutting groove.

[0027] Figure 9 This is a schematic diagram of the end-edge structure.

[0028] Figure 10 This is a schematic diagram of the end blade inclination angle.

[0029] Figure 11 This is a photograph of the actual wear on the cutting edge during the machining process, from unmachined to machined for 210 minutes.

[0030] Figure 12 This is a photograph of the cutting edge wear during the machining process, which lasted from 240 to 450 minutes.

[0031] Figure 13 This is a photograph of the cutting edge wear during the machining process, which lasted from 480 minutes to 660 minutes.

[0032] In the figure: 1-Clamping part; 2-Cutting part; 21-Rack; 21a-Long tooth; 21b-Short tooth; 210-Circumferential cutting edge; 211-Third front end face; 212-Fourth front end face; 213-Second lower end face; 22-Tool groove; 23-End cutting edge; 231-First front end face; 232-Second front end face; 233-First lower end face; 24-Cutting groove; 241-Long tooth cutting groove; 242-Short tooth cutting groove. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] Please see Figure 1-10This invention provides a stainless steel cutting tool, comprising a tool body, one end of which is a clamping part 1, and the other end is a cutting part 2 for cutting the workpiece. The cutting part 2 is formed by four racks 21 extending spirally along the central axis of the tool body. A groove 22 is formed between adjacent racks 21, and an end cutting edge 23 is provided at the top of each rack 21. The surface of the end cutting edge 23 is provided with a crescent to reduce the cutting resistance of the end cutting edge 23. A chip-receiving groove 24 is provided between every two adjacent end cutting edges 23 to discharge chips. The radial angles of adjacent racks 21 are different. The radial angles of adjacent racks 21 are 95°±1° (γ1) or 85°±1° (γ2), and the sum of two adjacent radial angles γ1+γ2 is 180°. Among them, the angle between the long tooth 21a and the short tooth 21b in front is 95°±1° (γ1), and the angle between the long tooth 21a and the short tooth 21b behind is 85°±1° (γ2). The rack 21 includes two long teeth 21a and two short teeth 21b arranged opposite each other. The two long teeth 21a correspond to the cutting edge 23 passing through the central axis of the cutter body, and the distance (e1) between the tips of the two long teeth 21a and the cutting edge 23 is 0.2-0.25 cm. The cutting edge inclination angle λ of the cutting edge 23 is 1.5°±0.2°. The cutting edge 23 includes a rearwardly inclined first front end face 231, a second front end face 232 located behind the first front end face 231, and a first lower end face 233 located below the first front end face 231. The first front end face 231, the second front end face 232, and the first lower end face 233 are all planar. The rake angle β3 of the cutting edge 23 is 4°±0.5°, the first clearance angle α3 of the cutting edge 23 is 10°±0.2°, and the second clearance angle α4 of the cutting edge 23 is 22°±0.4°. The cutting groove 22 is U-shaped. The rack 21 is provided with a peripheral cutting edge 210, which includes a rearwardly inclined third front end face 211, a fourth front end face 212 located behind the third front end face 211, and a second lower end face 213 located below the third front end face 212. The third front end face 211 and the second lower end face 213 are arc surfaces, the fourth front end face 212 is a plane, and the rear end face of the peripheral cutting edge 210 is also an arc surface and is back-shaved. The lower end face and the rear end face between adjacent racks 21 together form a U-shaped groove 22. The rake angle β1 of the peripheral cutting edge 210 is 5°±1°, the first clearance angle α1 of the peripheral cutting edge 210 is 10°±1°, and the second clearance angle α2 of the peripheral cutting edge 210 is 28°±2°. The cutting groove 24 includes a long-tooth cutting groove 241 and a short-tooth cutting groove 242. The long-tooth cutting groove 241 is a straight cutting groove, that is, the contour near the long tooth 21a is a straight line, and the tooth backlash angle gAL is 35°±0.2°. The short-tooth cutting groove 242 is an arc-shaped cutting groove, that is, the contour near the short tooth 21b is an arc, the tooth backlash angle gAS is 40°±0.2°, and the tooth backlash rake angle β2 is 4°±0.4°. The helix angle of the rack 21 is 40°±1°.

[0035] Setting the four racks into unequal-division helices reduces resonance and improves cutting quality and durability. U-shaped grooves ensure more even stress distribution across the tool during machining, reducing stress concentration. Variations in the angle and shape of the peripheral cutting edge's rake and stern angles enhance its sharpness and durability, resulting in smoother and more efficient cutting, further improving tool durability. Specific Implementation Example 1;

[0037] The total length L of the blade is 75cm. The diameter D1 of the clamping part 1 is 10cm, the diameter D of the cutting part 2 is 10cm±0.2m, the cutting edge length L1 of the rack 21 is 25cm, the groove length L2 of the groove 22 is 29cm, and the core thickness d4 is 6.2cm. The tooth width F of the long tooth 21a is 1.9cm, the cutting edge f1 of the peripheral cutting edge 210 of the long tooth 21a is 1.45cm, and the width f2 of the third front end face 211 of the peripheral cutting edge 210 is 0.65cm. The angle γ1 between the long tooth 21a and the front short tooth 21b is 95°±1°, and the angle γ2 between the long tooth 21a and the rear short tooth 21b is 85°±1°. The end cutting edges 23 of the two long teeth 21a are chamfered at the connection point, with a chamfer radius of 0.2cm. The width f3 of the first front end face 231 of the end cutting edge 23 is 0.9cm.

[0038] The tool structure differs from other tools in that it adopts a four-tooth rack peripheral cutting edge with a U-shaped groove design, and the rack uses an unequal-division helical design; the tool peripheral cutting edge has a rake angle of 5 degrees, and the rear end of the peripheral cutting edge has a double clearance angle and is back-shaved; the front end of the 24-tooth clearance groove is rounded with a radius of 0.57~0.6mm; after the tool is sharpened, it is blunted and rounded with a radius of 0.003~0.005mm.

[0039] In the cutting test of 304 stainless steel (S3000, F1000, ap: 20mm, ae: 0.2mm), a general-purpose coolant was used for thorough external cooling, and a dynamic milling method was employed. The changes in the circumferential cutting edge were observed under an electron microscope at 30x magnification every 30 minutes. The changes are as follows: Figure 11-13 .

[0040] Depend on Figure 11-13 It can be seen that after 11 hours (660 minutes) of cutting test, no major chipping occurred on the peripheral cutting edge of the tool. No significant tool vibration occurred throughout the cutting process, and the peripheral cutting edge wore slowly without exhibiting rapid wear and failure. The machine tool spindle load remained consistently at around 15%, demonstrating the stability of the structure and machining scheme.

[0041] During comparative experiments, the inventors discovered that when the radial angles of adjacent racks exceeded the range of 95°±1° (γ1) or 85°±1° (γ2), the cutting effect was unsatisfactory. When the radial angle γ1 increased, the cutting resistance of the tool remained almost unchanged, but the radial force on the tool increased, and the tool's vibration resistance decreased. Conversely, when the radial angle γ1 decreased, the cutting resistance of the tool also remained almost unchanged, but the radial force on the tool decreased, and the tool's vibration resistance improved. After repeated experiments with different radial angles, it was determined that a radial angle γ1 of 95°±1° was the most reasonable, resulting in a more balanced performance of the tool, good radial force, and good vibration resistance. This ensured both tool durability and reduced the occurrence of resonance.

[0042] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformations made under the concept of the present invention using the description and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A stainless steel cutting tool, comprising a tool body, one end of which is a clamping part (1), and the other end is a cutting part (2) for cutting a workpiece, the cutting part being formed by four racks (21) extending spirally along the central axis of the tool body, with a groove (22) formed between adjacent racks, and an end cutting edge (23) provided at the top of each rack (21); a chip-receiving groove (24) for discharging chips is provided between every two adjacent end cutting edges (23); characterized in that: The radial angles of adjacent racks (21) are different.

2. The stainless steel cutting tool according to claim 1, characterized in that: The radial angle between adjacent racks is 95°±1° or 85°±1°, and the sum of two adjacent radial angles is 180°.

3. The stainless steel cutting tool according to claim 2, characterized in that: The rack (21) includes two long teeth (21a) and two short teeth (21b) arranged opposite to each other. The two long teeth (21a) correspond to the end cutting edge (23) passing through the central axis of the cutter body, and the distance (e1) between the tips of the two long teeth (21a) and the end cutting edge (23) is 0.2-0.25cm. The cutting edge inclination angle (λ) of the end cutting edge (23) is 1.5°±0.2°.

4. The stainless steel cutting tool according to claim 3, characterized in that: The end blade (23) includes a rearwardly inclined first front end face (231), a second front end face (232) disposed behind the first front end face (231), and a first lower end face (233) disposed below the first front end face (231). The first front end face (231), the second front end face (232), and the first lower end face (233) are all planar.

5. The stainless steel cutting tool according to claim 4, characterized in that: The rake angle (β3) of the end blade is 4°±0.5°, the first clearance angle (α3) of the end blade is 10°±0.2°, and the second clearance angle (α4) of the end blade is 22°±0.4°.

6. The stainless steel cutting tool according to claim 3, characterized in that: The cutting groove (22) is U-shaped.

7. The stainless steel cutting tool according to claim 3, characterized in that: The rack (21) is provided with a peripheral blade (210), which includes a rearwardly inclined third front end face (211), a fourth front end face (212) disposed behind the third front end face (211), and a second lower end face (213) disposed below the third front end face (211). The third front end face (211) and the second lower end face (213) are arc surfaces, and the fourth front end face (212) is a plane.

8. The stainless steel cutting tool according to claim 7, characterized in that: The rake angle (β1) of the peripheral blade is 5°±1°, the first clearance angle (α1) of the peripheral blade is 10°±1°, and the second clearance angle (α2) of the peripheral blade is 28°±2°.

9. The stainless steel cutting tool according to claim 3, characterized in that: The cutting groove (24) includes a long tooth cutting groove (241) and a short tooth cutting groove (242). The long tooth cutting groove (241) is a straight cutting groove with a tooth back angle (gAL) of 35°±0.2°. The short tooth cutting groove (242) is an arc cutting groove with a tooth back angle (gAS) of 40°±0.2° and a tooth back rake angle (β2) of 4°±0.4°.

10. The stainless steel cutting tool according to claim 3, characterized in that: The helix angle of the rack (21) is 40°±1°.

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