Cbn soft material precision cutting insert

Abstract

The utility model relates to the field of precision cutting technology, especially a CBN soft material precision cutting blade, including CBN base body, CBN base body includes rake face, relief and the sharp cutting edge at the junction of rake face and relief, the first land enhanced platform and the second land enhanced platform are formed in order in the proximity of cutting edge of rake face, the one end of cutting edge is formed with the cusp, the cusp is arc, the arc radius of cusp is less than the total width of first land enhanced platform and second land enhanced platform, the utility model discloses CBN soft material precision cutting blade cutting edge is sharp land, can greatly reduce the cutting resistance of processing, thereby improves the anti -collapse ability of cutting edge, can also reduce the vibration of tool, tool bar, reduce the rigidity requirement of machine tool etc. CBN material and the groove type of the utility model are combined, and the sharp cutting edge can also greatly improve the surface roughness of the processing surface, burr, vibration line, roundness etc., and can also greatly improve the grade of machining accuracy.

Description

Technical Field

[0001] This utility model relates to the field of precision cutting technology, and specifically to a precision cutting insert for CBN soft material. Background Technology

[0002] Precision machining refers to high-precision cutting of workpieces in machining. Its main characteristics include a small depth of cut, typically requiring smaller depths of cut and feed rates to ensure machining accuracy and surface quality; and high precision requirements, with machining accuracy reaching IT8 to IT6 levels and surface roughness reaching Ra1.6 to 0.8 μm. Precision machining plays a vital role in mechanical manufacturing, enabling the achievement of high precision and excellent surface quality.

[0003] Existing precision cutting inserts are manufactured using materials such as tungsten steel, tungsten steel with coating, cermet, and cermet with coating through processes including grooving, denting, grinding, and die casting. When cutting soft ferrous metals (hardness less than HRC45) or performing high-precision turning, existing inserts suffer from poor surface finish, poor dimensional stability, and short tool life. Even with precision-ground cermet inserts, while a good surface finish can be achieved, the dimensional wear at the workpiece tip and end point may exceed the product tolerances. Furthermore, existing CBN (cubic boron nitride) inserts are designed only for machining cast iron and high-hardness products, making them completely unsuitable for high-precision turning of soft ferrous metals. Utility Model Content

[0004] The purpose of this utility model is to overcome the defects of the prior art and provide a CBN soft material precision cutting insert, which solves the problems of poor cutting surface finish, poor product dimensional stability and short tool life of existing cutting inserts. It also solves the problem that the wear of metal ceramic precision grinding inserts exceeds the product tolerance and that CBN is only suitable for machining high hardness products and not suitable for machining ferrous soft materials.

[0005] The technical solution to achieve the above objectives is: This utility model provides a CBN soft material precision cutting insert, including a CBN matrix, wherein the CBN matrix includes a rake face, a flank face, and a sharp cutting edge located at the junction of the rake face and the flank face; The rake face has a first edge enhancement platform and a second edge enhancement platform formed sequentially near the cutting edge; One end of the cutting edge is formed with a blade tip, which is arc-shaped and the radius of the arc of the blade tip is smaller than the total width of the first edge reinforcement platform and the second edge reinforcement platform.

[0006] A further improvement of this utility model of CBN soft material precision cutting insert is that a chip removal groove is provided on the rake face near the second cutting edge reinforcement platform, and the chip removal groove is arranged along the length direction of the CBN matrix.

[0007] A further improvement of this utility model of CBN soft material precision cutting insert is that the width of the first cutting edge reinforcement platform is greater than 0 mm and less than 0.3 mm, and the first cutting edge reinforcement platform is arranged along the length direction of the CBN matrix.

[0008] A further improvement of this utility model of CBN soft material precision cutting insert is that the width of the second cutting edge reinforcement platform is greater than 0 mm and less than 1.0 mm, and the second cutting edge reinforcement platform is arranged along the length direction of the CBN matrix.

[0009] A further improvement of this utility model of CBN soft material precision cutting insert is that the angle between the first cutting edge enhancement platform and the back face is greater than 75° and less than 90°.

[0010] A further improvement of this utility model of CBN soft material precision cutting insert is that the angle between the second cutting edge enhancement platform and the back face is greater than 45° and less than 90°.

[0011] A further improvement of this utility model of CBN soft material precision cutting insert is that the first cutting edge enhancement platform is horizontal or inclined with one side connected to the cutting edge having a higher height than the other side.

[0012] A further improvement of this utility model of CBN soft material precision cutting insert is that the second cutting edge reinforcement platform is horizontal, or inclined with one side connected to the first cutting edge reinforcement platform having a higher height than the other side.

[0013] A further improvement of this utility model of CBN soft material precision cutting insert is that the flank face is inclined and the angle between the flank face and the first edge reinforcement platform is an acute angle.

[0014] A further improvement of this utility model of CBN soft material precision cutting insert is that it also includes a metal matrix, wherein a joint groove adapted to the CBN matrix is ​​provided at one corner of the metal matrix; The CBN substrate is disposed within the bonding groove and is connected and fixed to the metal substrate.

[0015] The beneficial effects of this CBN soft material precision cutting insert are as follows: The cutting edge of this CBN soft material precision cutting insert is sharp, which greatly reduces cutting resistance during machining, thereby improving the cutting edge's resistance to chipping. It also reduces tool and tool holder vibration and lowers the rigidity requirements of the machine tool. The combination of CBN material and the groove shape of this insert, along with the sharp cutting edge, can also greatly improve the surface roughness, burrs, vibration marks, and roundness of the machined surface, and significantly improve the machining accuracy.

[0016] The tip radius of the precision cutting insert made of CBN soft material of this utility model is smaller than the total width of the first and second cutting edge reinforcement platforms. This facilitates the entry of fine and continuous iron chips into the chip removal groove during precision turning or precision boring.

[0017] This utility model of a CBN soft material precision cutting insert has a chip removal groove. The chip removal groove is a through groove, which can maximize the size of the chip removal groove, facilitate grinding with a grinding wheel, and effectively reduce processing costs.

[0018] This utility model of CBN soft material precision cutting insert is made of CBN material and is suitable for machining ferrous metals with a hardness of less than HRC45. It can improve machining accuracy, significantly improve the surface roughness and smoothness of the machined surface, reduce cutting load, and significantly improve tool life. When adjusting the machine or machining a single piece, it can greatly improve the product qualification rate. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural diagram of the CBN soft material precision cutting insert of this utility model.

[0020] Figure 2 This is a structural schematic diagram of the CBN soft material precision cutting insert of this utility model from another perspective.

[0021] Figure 3 for Figure 2 A magnified view of a portion of point A1 in the diagram.

[0022] Figure 4 for Figure 2 DD section view in the image.

[0023] Figure 5 for Figure 4 A magnified view of part A2 in the diagram.

[0024] Figure 6 This is a schematic diagram of the end face of the workpiece used in the comparative cutting experiment of this utility model.

[0025] Figure 7 This is a cross-sectional view of the workpiece processed in the comparative cutting experiment of this utility model. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0027] See Figure 1 This invention provides a precision cutting insert made of CBN soft material for machining ferrous metals with a hardness less than HRC45. Through special grooving and edge treatment of the CBN cutting tip, it combines the excellent properties of CBN cutting inserts, such as wear resistance, high hardness, chemical inertness, heat resistance, and low coefficient of friction, with the chip curling and chip removal performance of precision CNC cutting inserts. The groove design also appropriately improves the insert's anti-chipping performance. When machining ferrous soft metals with this CBN soft material precision cutting insert, the workpiece dimensional stability and surface finish are better, the first piece setup is easier to control in terms of dimensions, and batch processing results in more stable workpiece dimensions and a significantly increased service life. The structure of this CBN soft material precision cutting insert is described below with reference to the accompanying drawings.

[0028] See Figure 2 This diagram shows a structural schematic of the CBN soft material precision cutting insert of this utility model from another perspective. (See also...) Figure 3 It shows Figure 2 A magnified view of section A1 in the diagram. (See attached image.) Figure 5 It shows Figure 4 A magnified view of section A2 in the diagram. The following is in conjunction with... Figure 2 , Figure 3 and Figure 5 The structure of the CBN soft material precision cutting insert of this utility model is described.

[0029] like Figure 2 , Figure 3 and Figure 5 As shown, the CBN soft material precision cutting insert of this utility model includes a CBN substrate 21, which includes a rake face 21a, a flank face 21b, and a sharp cutting edge 211 located at the junction of the rake face 21a and the flank face 21b; a first edge reinforcement platform 212 and a second edge reinforcement platform 213 are sequentially formed on the rake face 21a near the cutting edge 211; a cutting tip 214 is formed at one end of the cutting edge 211, and the cutting tip 214 is arc-shaped, with the radius of the arc of the cutting tip 214 being smaller than the total width of the first edge reinforcement platform 212 and the second edge reinforcement platform 213.

[0030] Furthermore, the radius of the arc of the blade tip 214 is greater than 0.

[0031] The radius of the arc of the cutting tip 214 of this invention is smaller than the total width of the first cutting edge enhancement platform 212 and the second cutting edge enhancement platform 213, which facilitates the guidance of small and continuous iron chips during precision turning or precision boring. When a chip removal groove 215 is provided on the rake face 21a, small and continuous iron chips can be guided into the chip removal groove 215.

[0032] The cutting edge 211 of this utility model is a sharp cutting edge. The essence of cutting ferrous metal materials is the separation and removal of materials caused by shear deformation. The sharp cutting edge design of the cutting edge will greatly reduce the cutting resistance during machining, thereby improving the chipping resistance of the cutting edge. CBN material itself is relatively brittle, and the sharp cutting edge design of the cutting edge is extremely important when machining ferrous metals with a hardness of less than HRC45. This sharp cutting edge can reduce the vibration of the tool and tool holder, reduce the rigidity requirements of the machine tool, and greatly improve the surface roughness, burrs, vibration marks, roundness, etc. of the machined surface, and can also greatly improve the machining accuracy level.

[0033] The cutting edge 211 of this utility model is single-sided, and the CBN substrate 21 is a sheet. The single-sided cutting edge is conducive to grinding with a grinding wheel, and the single-sided cutting edge is conducive to the continuous chip removal and chip breaking.

[0034] In one specific embodiment of this utility model, such as Figures 1 to 5 As shown, a chip removal groove 215 is provided on the rake face 21a near the second cutting edge reinforcement platform 213, and the chip removal groove 215 is arranged along the length direction of the CBN substrate 21.

[0035] The chip removal groove 215 extends through two opposite sides of the CBN substrate 21. One side of the chip removal groove 215 is connected to the second cutting edge reinforcement platform 213. The chip removal groove 215 adopts a through groove design, which facilitates grinding with a grinding wheel. The through groove can maximize the size of the chip removal groove and improve the chip removal capacity.

[0036] Preferably, the chip removal groove 215 is an arc-shaped groove or a semi-circular groove.

[0037] Furthermore, such as Figure 2 and Figure 5 As shown, the width of the first cutting edge reinforcement platform 212 is greater than 0 mm and less than 0.3 mm, and the first cutting edge reinforcement platform 212 is arranged along the length direction of the CBN substrate 21.

[0038] Furthermore, the width of the second cutting edge reinforcement platform 213 is greater than 0 mm and less than 1.0 mm, and the second cutting edge reinforcement platform 213 is arranged along the length direction of the CBN substrate 21.

[0039] Furthermore, the angle between the first cutting edge enhancement platform 212 and the flank face 21b is greater than 75° and less than 90°. Preferably, the angle between the first cutting edge enhancement platform 212 and the flank face 21b is 83°, 81°, 79°, 77°, etc.

[0040] Furthermore, the angle between the second edge-reinforcing platform 213 and the flank face 21b is greater than 45° and less than 90°. Preferably, the angle between the second edge-reinforcing platform 213 and the flank face 21b is 75°, 68°, 66°, 64°, 62°, etc. Furthermore, the first edge-reinforcing platform 212 is horizontal, or inclined with one side connected to the cutting edge 211 higher than the other side. When inclined, the first edge-reinforcing platform 212 is slightly inclined, with an angle between it and the horizontal plane greater than 0° and less than 10°. Preferably, its inclination angle is 3°, 5°, 7°, etc.

[0041] Furthermore, the second cutting edge reinforcing platform 213 is horizontal, or inclined with one side connected to the first cutting edge reinforcing platform 212 being higher than the other side. When inclined, the second cutting edge reinforcing platform 213 is slightly inclined, with an angle greater than 0° and less than 15° with the horizontal plane. Preferably, its inclination angle is 9°, 12°, 15°, etc.

[0042] Furthermore, the flank face 21b is inclined, and the angle between the flank face 21b and the first edge-reinforcing platform 212 is an acute angle. Alternatively, the angle between the flank face 21b and the horizontal portion of the rake face 21a is an acute angle. Preferably, the angle between the flank face 21b and the horizontal portion of the rake face 21a is 7°, 9°, 11°, etc.

[0043] In one specific embodiment of this utility model, such as Figure 2 As shown, the CBN soft material precision cutting insert of this utility model also includes a metal substrate 22, and a joint groove adapted to the CBN substrate 21 is provided at one corner of the metal substrate 22; the CBN substrate 21 is disposed in the joint groove and is connected and fixed to the metal substrate 22.

[0044] The metal substrate 22 is provided with a mounting groove 221 to facilitate the installation and fixing of the cutting blade.

[0045] Preferably, the metal substrate 22 is a tungsten carbide substrate.

[0046] The CBN substrate 21 is preferably a sheet, which is disposed in the bonding groove of the metal substrate 22 and welded and fixed to the metal substrate 22, for example, by means of high frequency induction brazing, vacuum brazing or laser brazing.

[0047] Furthermore, such as Figure 2As shown, a groove 222 is provided on the metal substrate 22 to connect with the chip removal groove 215 on the CBN substrate 21. The other end of the groove 222 is located on the corresponding side of the metal substrate 22 to facilitate chip removal during the cutting process.

[0048] The CBN soft material precision cutting insert of this invention has outstanding performance in precision cutting. The following is a comparative experiment on the cutting of the same product.

[0049] The workpiece to be cut is Figure 6 and Figure 7 The Q235 precision seamless tube shown has an outer diameter of φ20mm, an inner diameter of φ10mm, a length of L of 10mm, and an inner hole roughness of 1.6. The machining target is an inner hole of φ11mm. The cutting difficulties include the tendency to stick to the tool, the easy generation of edge-shaped cuttings during cutting due to the softness and good ductility of the material, and the easy generation of burrs during the cutting process.

[0050] Experiment 1: Using the CBN soft material precision cutting insert of this invention, workpieces were machined with a cutting allowance of 0.05 mm (single-sided), a spindle speed of 2000 rpm, and a feed rate of 0.05 mm / rpm. The machining quantities were 1 to 5 pieces, with machining accuracy and visual surface finish meeting requirements; 6 to 30 pieces, with machining accuracy and visual surface finish meeting requirements; 31 to 100 pieces, with machining accuracy and visual surface finish meeting requirements; and 101 to 200 pieces, with machining accuracy and visual surface finish meeting requirements. Tool diameter compensation: During the machining process, a total of five tool compensations were performed, with a total compensation of 0.02 mm. Experiment 2: Using a Japanese Tungaloy brand insert, model CCMT060202-AH725, with a ceramic-coated full-circumferential cutting edge, the workpiece was machined. The cutting allowance was 0.3mm (single side), the spindle speed was 2000 rpm, and the feed rate was 0.08mm / rpm. For machining quantities of 1 to 5 pieces, the machining accuracy and visual surface finish met the requirements. For machining quantities of 6 to 30 pieces, the machining accuracy and visual surface finish still met the requirements. For machining quantities of 31 to 100 pieces, the machining accuracy and visual surface finish did not meet the requirements. Tool diameter compensation: the surface finish after tool compensation exceeded the tolerance, requiring insert replacement.

[0051] Experiment 3 used Tungaloy (Japan) brand cermet inserts, model DCGT070201FR-J10 NS530, to machine workpieces. The cutting allowance was 0.05mm (single-sided), the spindle speed was 2000 rpm, and the feed rate was 0.05mm / rpm. The machining quantity was 1 to 5 pieces, and the machining accuracy and visual surface finish met the requirements. Tool diameter compensation was required every 2 pieces. The machining quantity was 6 to 30 pieces, and the machining accuracy and visual surface finish met the requirements. Tool diameter compensation was required every 2 pieces. The machining quantity was 31 to 100 pieces, and the machining accuracy and visual surface finish met the requirements. Tool diameter compensation was required every 2 pieces. The machining quantity was 101 to 200 pieces, and the machining accuracy and visual surface finish met the requirements. Tool diameter compensation was required every 2 pieces. The cermet inserts required continuous tool compensation, which was cumbersome and labor-intensive.

[0052] Experiment 4 used a Japanese Kyocera brand ceramic-coated single-sided cutting edge insert, model TPGH110302L, to machine workpieces. The cutting allowance was 0.1mm (single-sided), the spindle speed was 2000 rpm, and the feed rate was 0.06mm / rpm. For machining quantities of 1 to 5 pieces, the machining accuracy and visual surface finish met the requirements; tool diameter compensation was not required. For machining quantities of 6 to 30 pieces, the machining accuracy and visual surface finish met the requirements; tool diameter compensation was continuously adjusted as needed. For machining quantities of 31 to 100 pieces, the machining accuracy and visual surface finish met the requirements; tool diameter compensation was continuously adjusted as needed. For machining quantities of 101 to 200 pieces, the machining accuracy and visual surface finish did not meet the requirements. The ceramic-coated single-sided cutting edge insert had good machining accuracy and surface finish, but frequent tool compensation was required.

[0053] The CBN soft material precision cutting insert of this invention can ensure that the machining accuracy and surface finish meet the requirements when cutting soft materials. It also requires fewer tool compensations and smaller tool compensation amounts, which can greatly save inspection and machine setup time and significantly improve the quality stability of the product.

[0054] The CBN soft material precision cutting insert of this invention has the following characteristics when machining ferrous metals with a hardness of less than HRC45: Improved machining accuracy; The surface roughness and smoothness of the machined surface are greatly improved, and the machining of soft materials is particularly outstanding; Reduce cutting load; Significantly improves blade life; When adjusting the machine or processing individual pieces, the product qualification rate is greatly improved; CBN material exhibits excellent properties such as high hardness, wear resistance, heat resistance, chemical inertness, high thermal conductivity, and low coefficient of friction.

[0055] The present invention has been described in detail above with reference to the accompanying drawings and embodiments. Those skilled in the art can make various modifications to the present invention based on the above description. Therefore, certain details in the embodiments should not be construed as limiting the present invention, and the scope of protection of the present invention shall be defined by the appended claims.

Claims

1. A precision cutting insert made of CBN soft material, characterized in that, The CBN matrix includes a rake face, a flank face, and a sharp cutting edge located at the junction of the rake face and the flank face. The rake face has a first edge enhancement platform and a second edge enhancement platform formed sequentially near the cutting edge; One end of the cutting edge is formed with a blade tip, which is arc-shaped and the radius of the arc of the blade tip is smaller than the total width of the first edge reinforcement platform and the second edge reinforcement platform.

2. The CBN soft material precision cutting insert as described in claim 1, characterized in that, The rake face is provided with a chip removal groove near the second cutting edge enhancement platform, and the chip removal groove is provided along the length direction of the CBN matrix.

3. The CBN soft material precision cutting insert as described in claim 1, characterized in that, The width of the first cutting edge reinforcement platform is greater than 0 mm and less than 0.3 mm, and the first cutting edge reinforcement platform is arranged along the length direction of the CBN matrix.

4. The CBN soft material precision cutting insert as described in claim 1, characterized in that, The width of the second cutting edge reinforcement platform is greater than 0 mm and less than 1.0 mm, and the second cutting edge reinforcement platform is arranged along the length direction of the CBN matrix.

5. The CBN soft material precision cutting insert as described in claim 1, characterized in that, The angle between the first cutting edge enhancement platform and the back face is greater than 75° and less than 90°.

6. The CBN soft material precision cutting insert as described in claim 1, characterized in that, The angle between the second cutting edge enhancement platform and the back face is greater than 45° and less than 90°.

7. The CBN soft material precision cutting insert as described in claim 1, characterized in that, The first cutting edge enhancement platform is horizontal or inclined, with one side connected to the cutting edge having a higher height than the other side.

8. The CBN soft material precision cutting insert as described in claim 1, characterized in that, The second cutting edge enhancement platform is horizontal or inclined, with one side of the platform connected to the first cutting edge enhancement platform being higher than the other side.

9. The CBN soft material precision cutting insert as described in claim 1, characterized in that, The back face is inclined, and the angle between the back face and the first edge enhancement platform is an acute angle.

10. The CBN soft material precision cutting insert as described in claim 1, characterized in that, It also includes a metal substrate, wherein a joint groove adapted to the CBN substrate is provided at one corner of the metal substrate; The CBN substrate is disposed within the bonding groove and is connected and fixed to the metal substrate.

Images