A cutting tool with surface in-situ self-generated micro-texture and its preparation method

Abstract

The present invention discloses a surface in-situ self-generated micro-textured tool and a preparation method thereof, belonging to the technical field of tool processing. The surface in-situ self-generated micro-textured tool includes a tool substrate, and micro-textured graphite papers are arranged on both the upper and lower surfaces of the tool substrate; the thickness of the graphite paper is 0.1 - 0.5 mm. The preparation process of the preparation method includes the following steps: S1, preparing the micro-textured graphite paper; S2, sintering the micro-textured graphite paper and tool powder in a mold to prepare a micro-textured tool blank; S3, cutting the micro-textured tool blank into a rough tool blank, performing grinding and chamfering treatment on the rough tool blank, and then polishing and forming. By combining the tool material sintering technology with the laser processing technology, the micro-textured tool can be prepared after the tool material is sintered, cut, rough ground, fine ground, lapped, and polished, improving the preparation efficiency of the micro-textured tool and having a low production cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of tool processing, and particularly relates to a tool with in-situ self-generated micro-textures on the surface and a preparation method thereof. Background Art

[0002] Disclosing the information of this background art section is only intended to enhance the overall understanding of the present invention, and it is not necessarily regarded as an admission or an implication in any form that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] Tools play a very important role in the cutting process. The quality of a tool needs to be judged by its cutting performance and service life. Among them, tool wear is one of the factors affecting tool life and cutting performance. When cutting difficult-to-machine materials, the friction and cutting heat between the tool and the workpiece will cause rapid wear of the tool, resulting in premature failure of the tool. The cutting efficiency also begins to decrease, and then the surface of the workpiece is damaged. Since it is difficult for the cutting fluid to enter the tool-chip contact area during high-speed cutting, it is still difficult to achieve an ideal degree of wear of the tool even under lubricated conditions. These reasons cause rapid tool wear and poor workpiece quality. In order to reduce friction and wear and improve tool life, micro-textured tools are used in more and more machining occasions. Micro-textured tools have the functions of improving the surface lubrication state and reducing friction and wear, and are also more and more widely used in the engineering field.

[0004] A micro-textured tool is an innovative tool with micro-textures or structures machined on the tool surface. As a technology in the field of precision machining, its definition usually involves introducing specific geometric structures on the tool surface or near-surface area, which can improve problems such as wear, short tool life, and low cutting efficiency that occur in the traditional tool cutting process, so as to improve the cutting performance of the tool. So far, the tool surface texturing technology has been successfully applied to turning, drilling, and milling operations. The micro-textures can be regular geometric shapes, such as circles, squares, or triangles, or irregular patterns. Their size, shape, and distribution pattern have a significant impact on the performance of the tool, such as friction, wear, chip control, and cutting heat. For example, it can reduce friction and wear and increase the load-bearing capacity.

[0005] For example, Chinese Patent Document CN103042375A discloses a processing method for preparing regular micro-textures on the surface of a metal matrix or coating, including mask preparation and texture processing; Mask preparation: S1: Select a metal or inorganic material as the mask plate. S2: Use a laser processing method to machine a pattern on the plate. Texture processing: S1: Grind and clean the surface of the metal matrix or coating. S2: Fix the mask to the surface of the metal matrix or coating to be processed, and use the micro-abrasive jet machining technology for erosion machining. This method has the advantages of wide application range and low cost, but its processing steps are cumbersome and the micro-texture preparation efficiency is low.

[0006] The design process of surface micro-textures is highly related to the specific functions of any application scenarios that require textures. The quality of micro-textures is also greatly affected by the forming methods. There are many existing micro-texture processing methods, but they have high costs, long processing cycles, and some micro-texture tools require adding lubricants to the textures. Therefore, suitable micro-texture forming methods and sizes have a significant impact on the performance of the tools. Summary of the Invention

[0007] In order to solve the deficiencies of the prior art, the purpose of the present invention is to provide a surface in-situ self-generated micro-texture tool and its preparation method. This method has the advantages of one-time forming of the micro-textures on the tool surface, higher preparation efficiency of the micro-texture tool, and good tool forming effect.

[0008] The preparation method of the in-situ self-generated micro-texture tool described in the present invention: Based on the tribology principle of micro-textures, design the micro-texture morphology, use laser processing technology to prepare micro-textured graphite paper. During the tool sintering process, replace the conventional graphite paper with the micro-textured graphite paper, place the micro-textured graphite paper on the upper and lower surfaces in contact with the powder respectively. Through the occupation of positions by the micro-protrusions on the graphite paper in the tool material, micro-groove textures are formed in-situ on the rake face of the tool. The micro-texture tool prepared by the preparation method provided by the present invention has good forming effect, high precision, high efficiency, good comprehensive mechanical properties, realizes the interweaving of hard cermet materials and soft lubricating graphite on the surface, has good tool life, and the surface roughness of the machined workpiece is low, and the friction coefficient is significantly reduced in the friction experiment.

[0009] In order to achieve the above purpose, the technical solution of the present invention is as follows:

[0010] In the first aspect, the present invention provides a surface in-situ self-generated micro-texture tool, including a tool substrate, and at least one surface of the tool substrate is provided with micro-textured graphite paper; the thickness of the graphite paper is 0.1 - 0.5 mm.

[0011] Further, micro-textured graphite papers are provided on both the upper and lower surfaces of the tool substrate.

[0012] Further, the thickness of the graphite paper is 0.2 - 0.4 mm. Using graphite paper has low cost and high processing efficiency. If graphite is used, it is more difficult to process, and if graphite is placed in a spark plasma sintering device, there will be different degrees of overflow phenomenon. The graphite paper of the present invention, as a flexible intermediate layer, can better fill the tiny gaps between the powder and the micro-grooves.

[0013] In one or more embodiments, the micro-texture is of a groove type. Among them, in the groove-type micro-texture, the average groove width is 20 - 300 μm, preferably 80 - 150 μm, more preferably 95 - 130 μm, and specifically can be 95 μm, 98 μm, 100 μm, 105 μm, 106, 108, 110 μm, 115 μm, 120 μm, etc.; the average spacing is 20 - 300 μm, preferably 90 - 250 μm, more preferably 140 - 155 μm, and specifically can be 95 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 147 μm, 150 μm, 152 μm, 155 μm, 160 μm, 170 μm, 180 μm, 190 μm, 195 μm, 243 μm, etc.; the average depth is 5 - 150 μm, preferably 20 - 80 μm, more preferably 40 - 80 μm, and specifically can be 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 80 μm, etc.

[0014] Further, the groove type includes a straight type.

[0015] In one or more embodiments, the tool substrate is a tool with a cemented carbide substrate. The cemented carbide substrate includes a (W,Ti)C-based metal substrate or a (WC-6Co)-based metal substrate, and specifically can be (W,Ti)C / Ni / Mo / Co or YG6 (WC-6Co), preferably (W,Ti)C / Ni / Mo / Co. The volume ratio of (W,Ti)C, Ni, Mo, and Co is (80 - 90):(2 - 5):(5 - 8):(4 - 7), preferably 85:3.5:6.5:5, that is, (W,Ti)C(85 vol%) / Ni(3.5 vol%) / Mo(6.5 vol%) / Co(5 vol%).

[0016] In a second aspect, the present invention provides a method for preparing the above-mentioned tool with surface in-situ self-generated micro-texture, including the following steps:

[0017] S1. Prepare micro-textured graphite paper;

[0018] S2. Place the micro-textured graphite paper and tool powder in a mold and sinter them to prepare a micro-textured tool blank;

[0019] S3. Cut the micro-textured tool blank into a rough tool, and successively perform grinding and chamfering on the rough tool, and then polish it into shape.

[0020] In one or more embodiments, in step S1, the preparation process of the micro-textured graphite paper includes: designing the micro-texture morphology size on the tool surface, and using laser processing technology to prepare the micro-textured graphite paper.

[0021] Furthermore, the morphological dimensions of the micro-texture on the tool surface need to be designed according to the basic action mechanism of the micro-textured tool. Specifically, measurements are carried out in accordance with the tool-chip contact direction on the rake face of the tool and the tool wear position, and the influences such as material forming during the sintering process of the tool matrix material are calculated. The basic morphology of the micro-texture on the tool surface is designed using drawing software (such as AutoCAD).

[0022] Furthermore, in the laser processing technology, the spot diameter is 2 - 100 μm, the frequency is 10 - 100 kHz, the laser processing speed is 2 mm / s - 800 mm / s, and the laser processing power is 5 - 80 W.

[0023] Furthermore, in step S1, the groove width of the micro-textured graphite paper is 20 - 300 μm, preferably 80 - 110 μm, more preferably 95 - 105 μm, and specifically can be 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, etc.; the spacing is 20 - 300 μm, preferably 90 - 260 μm, more preferably 100 - 250 μm, and specifically can be 100 μm, 150 μm, 200 μm, 250 μm, etc.; the depth is 5 - 200 μm, preferably 50 - 200 μm, more preferably 70 - 180 μm, and specifically can be 40 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, etc.

[0024] In one or more embodiments, in step S2, the mold is a graphite mold. The graphite mold includes an upper punch and a lower punch.

[0025] Among them, the micro-textured graphite paper is placed on the upper and lower surfaces of the tool powder and is closely attached. When the micro-textured graphite paper and the tool powder are placed in the mold, from bottom to top are the lower punch, the micro-textured graphite paper, the tool powder, the micro-textured graphite paper, and the upper punch, so that finally the graphite paper containing micro-textures is formed on the upper and lower surfaces of the tool.

[0026] In one or more embodiments, in step S2, the tool powder is a composite powder of cermet materials, and its preparation process is not specifically limited. Taking (W,Ti)C / Ni / Mo / Co as an example, it is ultrasonically dispersed for 30 min in a certain proportion, ball milled at high energy for 48 h, dried for 48 h, and screened through a 100-mesh sieve for standby.

[0027] In one or more embodiments, in step S2, the micro-textured tool blank is disc-shaped. Furthermore, the diameter of the disc-shaped blank of the micro-textured tool is 25 - 35 mm, and the thickness is 3 - 5 mm.

[0028] In one or more embodiments, in step S2, the sintering is carried out in a vacuum atmosphere.

[0029] The densification degree and mechanical properties of the cermet prepared from the tool substrate in a vacuum atmosphere are the highest.

[0030] The sintering includes, but is not limited to, spark plasma sintering, hot pressing sintering, and hot isostatic pressing sintering. A certain pressure can be applied during the sintering process to ensure that the powder can be filled into the micro-textured graphite paper for molding.

[0031] Furthermore, the sintering temperature is 1300 - 1500 °C, preferably 1350 - 1450 °C, the holding time is 5 - 20 minutes, preferably 10 - 15 minutes, and the sintering pressure is 10 - 60 MPa, preferably 20 - 40 MPa.

[0032] In one or more embodiments, in step S3, the cutting is carried out by wire electrical discharge machining. It is necessary to ensure that the main and secondary cutting edges of each tool tip of the rough blank are parallel to the boundary of the square micro-textured unit, and the distance between the boundary and the micro-texture is kept between 1 mm and 2 mm. The length of the rough tool blank cut is 13 mm × width 13 mm × thickness 4 mm.

[0033] In one or more embodiments, in step S3, the rough tool blank is a cuboid, wherein the length and width are equal, the upper and lower surfaces of the rough tool blank are micro-textured surfaces, and the other surfaces are non-micro-textured surfaces.

[0034] In one or more embodiments, in step S3, the grinding includes grinding the non-micro-textured surface and the micro-textured surface of the rough tool blank respectively; the grinding includes rough grinding and fine grinding.

[0035] Furthermore, the grinding treatment of the non-micro-textured surface of the rough tool blank is to rough grind the 4 non-micro-textured surfaces. The rough grinding is carried out by a high-precision grinding machine. Specifically: the tool blank is rough ground successively with 200-mesh and 600-mesh diamond grinding wheels. The rough grinding is carried out in a way of mutual correction of the opposite surfaces. The rough grinding sequence is: first, the side surface without micro-texture is rough ground, and then the side surface parallel to it is rough ground. The feed per pass is 0.001 - 0.01 mm, preferably 0.004 - 0.006 mm. When the cumulative feed of the first pair of parallel side surfaces reaches 0.05 - 0.15 mm respectively, the other two parallel side surfaces are replaced for rough grinding. During the rough grinding process, an optical microscope is used for observation at any time. The magnification of the optical microscope is 5 times.

[0036] Further, the micro-textured surface of the rough tool blank is polished, specifically, the two micro-textured surfaces of the cut rough tool blank are rough-ground and finish-ground. Specifically: diamond sandpaper is used to rough-grind and finish-grind the two micro-textured surfaces of the cut tool blank, and diamond sandpaper with different mesh numbers is used for rough-grinding and finish-grinding in sequence. Preferably, the mesh number is 200 - 1500 mesh, specifically, it can be 200 mesh, 800 mesh, and 1500 mesh.

[0037] In one or more embodiments, in step S3, the chamfering process is to chamfer the tool blank, and the chamfer radius is 0.5 - 1 mm, preferably 0.7 - 0.9 mm. A blade grinding machine is used for chamfering.

[0038] In one or more embodiments, in step S3, before polishing and forming, the six surfaces of the tool blank are ground to remove the scratches formed on each surface during the rough grinding process. The grinding tool is a grinding glass with a specification of 1000 mesh, and a water-soluble diamond W0.5 grinding paste is used for manual grinding.

[0039] In one or more embodiments, in step S3, a fully automatic polishing machine is used to polish the tool blank, and the specification of the diamond polishing agent is W2.5 particle size.

[0040] In the method of the present invention, those not specifically limited can be in accordance with the prior art.

[0041] One or some of the above technical solutions have the following advantages or beneficial effects:

[0042] (1) In the preparation method of the surface in-situ self-generated micro-textured tool of the present invention, the tool material sintering technology is combined with the laser processing technology. After the tool material is sintered, the micro-textured tool can be prepared through cutting, rough grinding, finish grinding, grinding, and polishing, which improves the preparation efficiency of the micro-textured tool and has a low production cost.

[0043] (2) Based on the micro-texture tribology principle, the present invention designs the micro-texture morphology, uses the laser processing technology to prepare the micro-textured graphite paper. During the tool sintering process, the micro-textured graphite paper is used instead of the conventional graphite paper, and the micro-textured graphite paper is placed on the upper and lower surfaces in contact with the powder. Through the occupation of the micro-protrusions on the graphite paper in the tool material, the micro-groove texture is formed in-situ on the rake face of the tool. The micro-textured tool prepared by the preparation method provided by the present invention has good forming effect, high precision, high efficiency, and good comprehensive mechanical properties (hardness greater than 19 GPa, fracture toughness greater than 7 MPa·m 1 / 2 1 / 2, flexural strength 800 MPa), realizes the interweaving of the hard cermet material surface and the soft lubricating graphite, has a good tool life, and the surface roughness of the machined workpiece is low. In the friction experiment, the friction coefficient is significantly reduced (the friction coefficient is as low as 0.13).

[0044] (3) The self-generated micro-textured tool prepared by the present invention has a good forming effect. Compared with preparing micro-textures after the tool is sintered and formed, the rake face of the in-situ self-generated micro-textured tool has no obvious defects, and surface residual compressive stress is formed on the rake face, with stronger comprehensive mechanical properties, overcoming the problem of surface damage in the micro-texture tool preparation technology.

[0045] (4) In the self-generated micro-textured tool prepared by the present invention, the graphite paper and the tool material matrix are sintered into an integral body during the sintering process. During the post-treatment process after the tool is formed, the graphite is preserved in the grooves, and in the friction experiment, the dual coupling effect of the micro-texture and graphite can be realized.

[0046] (5) Compared with using a micro-mill to prepare a graphite punch in the prior art, the present invention uses laser processing of graphite paper. The diameter of the milling cutter limits the minimum feature size (usually ≥50 μm), while the laser spot diameter is small, with higher precision, and the preparation process is simpler; in addition, the processing efficiency of laser processing of graphite paper is higher, and if processing a graphite punch, the processing time will be significantly extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The specification drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0048] Figure 1 It is a schematic diagram of the relative positions of the graphite paper and the tool powder in the mold in the embodiment of the present invention;

[0049] Figure 2 It is a surface diagram of the surface in-situ self-generated micro-textured tool in Embodiment 1 of the present invention;

[0050] Among them, 1 is the upper punch; 2 is the tool powder; 3 is the graphite paper; 4 is the lower punch. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0051] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in combination with specific embodiments.

[0052] In the embodiment, the thickness of the graphite paper is 0.3 mm, which is a commercially available product.

[0053] The micro-groove texture is a groove-type micro-texture.

[0054] Embodiment 1

[0055] The present invention prepares a (W,Ti)C / Ni / Mo / Co micro-textured tool by in-situ self-generation method of spark plasma sintering. The micro-texture is of groove type, the included angle between the micro-groove texture and the cutting edge is 45°, the average groove width is 98μm, the average spacing is 152μm, and the average depth is 40μm, as Figure 1 shown.

[0056] The preparation method of the surface in-situ self-generated micro-textured tool: includes the following steps:

[0057] (1) Use drawing software to draw according to the designed shape and size of the micro-texture.

[0058] (2) Import the above drawing file into the fiber laser marking machine software (frequency 30kHz, laser processing speed 50mm / s, laser processing power 27W) to prepare micro-groove textures on the graphite paper. The included angle between the prepared micro-groove textures and the cutting edge is 45°, the groove width is 0.1mm, the spacing is 0.15mm, and the depth is 0.13mm.

[0059] (3) Place the prepared micro-textured graphite paper and the tool material composite powder in a graphite mold, and use a spark plasma sintering device in a vacuum atmosphere, with a sintering temperature of 1400°C and a holding time of 10min, to prepare a disc-shaped blank of (W,Ti)C-based micro-textured cermet material tool with a diameter of 30mm and a thickness of 4mm.

[0060] (4) Use wire electrical discharge machining to cut the prepared disc-shaped blank of (W,Ti)C-based micro-textured cermet material. It is necessary to ensure that the main and secondary cutting edges of each cutting tip of the rough blank should be parallel to the boundary of the square micro-texture unit, and the boundary distance from the micro-texture is between 1mm and 2mm. The length of the rough blank of the cut tool is 13mm × width 13mm × thickness 4mm.

[0061] (5) Use a high-precision grinding machine to rough grind the 4 non-micro-textured surfaces of the tool rough blank. Among them, the high-precision grinding machine successively uses 200-mesh and 600-mesh diamond grinding wheels to rough grind the tool rough blank. The rough grinding is carried out in a way of mutual correction of the opposite sides. The rough grinding sequence is: first rough grind the side without micro-texture, and then rough grind the parallel side. Each feed amount is 0.005mm. When the cumulative feed amount of the first pair of parallel sides reaches 0.1mm respectively, replace the other two parallel sides for rough grinding. Observe at any time with a 5-fold optical microscope during the rough grinding process.

[0062] (6) Use diamond sandpaper to rough grind and finish grind the two micro-textured surfaces of the cut tool rough blank. Among them, the diamond sandpaper successively uses 200-mesh, 800-mesh, and 1500-mesh diamond sandpaper for rough grinding and finish grinding.

[0063] (7) Chamfer the rough-ground tool blank using a tool grinder with a chamfer radius of 0.8 mm.

[0064] (8) Grind the six surfaces of the tool blank using abrasive glass to remove the scratches formed on each surface during rough grinding. Among them, the abrasive glass has a specification of 1000 mesh, and water-soluble diamond W0.5 grinding paste is used.

[0065] (9) Polish the tool blank using a fully automatic polishing machine, where the diamond polishing agent has a specification of W2.5 grit.

[0066] The surface micro-groove texture prepared by the in-situ self-generation method has an average width of 98 μm, an average spacing of 152 μm, and an average depth of 40 μm after rough grinding - fine grinding - lapping - polishing. The cermet tool material is prepared into a 3 mm × 4 mm × 30 mm ceramic spline through cutting - rough grinding - fine grinding - lapping - polishing steps, and its mechanical properties are measured as follows: hardness 19.38 GPa, fracture toughness 7.74 MPa·m 1 / 2 、flexural strength 866 MPa. Through friction experiments, under the condition of a test force of 10 N, the friction coefficient is measured to be 0.13.

[0067] Example 2

[0068] In this example, a micro-textured (W,Ti)C-based cermet tool is prepared by the in-situ self-generation method. The preparation method is the same as that of Example 1, except that the width of the micro-textured graphite paper groove is 100 μm, the spacing is 100 μm, and the depth is 130 μm. The average width of the micro-groove texture prepared by the post-treatment process after the cermet tool material goes through the cutting - rough grinding - fine grinding - lapping - polishing steps is 105 μm, the average spacing is 95 μm, and the average depth is 30 μm. The cermet tool material is prepared into a 3 mm × 4 mm × 30 mm ceramic spline through cutting - rough grinding - fine grinding - lapping - polishing steps, and its mechanical properties are measured as follows: hardness 19.15 GPa, fracture toughness 7.68 MPa·m 1 / 2 、flexural strength 835.23 MPa. Through friction experiments, under the condition of a test force of 10 N, the friction coefficient is measured to be 0.14.

[0069] Example 3

[0070] In this example, a micro-textured (W,Ti)C-based cermet cutting tool was prepared by the in-situ self-generation method. The preparation method is the same as that in Example 1, except that the width of the grooves in the micro-textured graphite paper is 100 μm, the spacing is 200 μm, and the depth is 130 μm. The average width of the micro-groove texture prepared by the post-treatment process of the cermet cutting tool material through the steps of cutting - rough grinding - fine grinding - lapping - polishing is 108 μm, the average spacing is 195 μm, and the average depth is 50 μm. The cermet cutting tool material was prepared into a 3 mm × 4 mm × 30 mm ceramic spline through the steps of cutting - rough grinding - fine grinding - lapping - polishing, and its mechanical properties were measured as follows: hardness 19.26 GPa, fracture toughness 7.33 MPa·m 1 / 2 and flexural strength 830.15 MPa. Through the friction experiment, under the condition that the test force is 10 N, the friction coefficient was measured to be 0.15.

[0071] Example 4

[0072] In this example, a micro-textured (W,Ti)C-based cermet cutting tool was prepared by the in-situ self-generation method. The preparation method is the same as that in Example 1, except that the width of the grooves in the micro-textured graphite paper is 100 μm, the spacing is 250 μm, and the depth is 130 μm. The average width of the micro-groove texture prepared by the post-treatment process of the cermet cutting tool material through the steps of cutting - rough grinding - fine grinding - lapping - polishing is 110 μm, the average spacing is 243 μm, and the average depth is 60 μm. The cermet cutting tool material was prepared into a 3 mm × 4 mm × 30 mm ceramic spline through the steps of cutting - rough grinding - fine grinding - lapping - polishing, and its mechanical properties were measured as follows: hardness 19.12 GPa, fracture toughness 7.71 MPa·m 1 / 2 and flexural strength 825.33 MPa. Through the friction experiment, under the condition that the test force is 10 N, the friction coefficient was measured to be 0.16.

[0073] Example 5

[0074] In this example, a micro-textured (W,Ti)C-based cermet cutting tool was prepared by the in-situ self-generation method. The preparation method is the same as that in Example 1, except that the width of the grooves in the micro-textured graphite paper is 100 μm, the spacing is 150 μm, and the depth is 180 μm. The average width of the micro-groove texture prepared by the post-treatment process of the cermet cutting tool material through the steps of cutting - rough grinding - fine grinding - lapping - polishing is 95 μm, the average spacing is 155 μm, and the average depth is 80 μm. The cermet cutting tool material was prepared into a 3 mm × 4 mm × 30 mm ceramic spline through the steps of cutting - rough grinding - fine grinding - lapping - polishing, and its mechanical properties were measured as follows: hardness 19.13 GPa, fracture toughness 7.65 MPa·m 1 / 2 and flexural strength 845.33 MPa. Through the friction experiment, under the condition that the test force is 10 N, the friction coefficient was measured to be 0.15.

[0075] Example 6

[0076] In this example, a micro-textured tool was prepared by in-situ self-generation method. The preparation method was the same as that of Example 1, except that the width of the micro-textured graphite paper groove was 100 μm, the spacing was 150 μm, and the depth was 70 μm. The average width of the micro-groove texture prepared by the post-treatment process of the cermet tool material through the steps of cutting - rough grinding - fine grinding - lapping - polishing was 106 μm, the average spacing was 147 μm, and the average depth was 20 μm. The cermet tool material was prepared into a 3 mm × 4 mm × 30 mm ceramic spline through the steps of cutting - rough grinding - fine grinding - lapping - polishing, and its mechanical properties were measured as follows: hardness 19.33 GPa, fracture toughness 7.66 MPa·m 1 / 2 and flexural strength 833.52 MPa. Through the friction experiment, under the condition of a test force of 10 N, the friction coefficient was measured to be 0.14.

[0077] Comparative Example 1

[0078] As described in Example 1, the preparation method was the same as that of Example 1, except that conventional graphite paper was used, and a non-textured tool was prepared by the post-treatment process of the cermet tool material through the steps of cutting - rough grinding - fine grinding - lapping - polishing. The cermet tool material was prepared into a 3 mm × 4 mm × 30 mm ceramic spline through the steps of cutting - rough grinding - fine grinding - lapping - polishing, and its mechanical properties were measured as follows: hardness 19.15 GPa, fracture toughness 6.75 MPa·m 1 / 2 and flexural strength 796.83 MPa. Through the friction experiment, under the condition of a test force of 10 N, the friction coefficient was measured to be 0.35.

[0079] Comparative Example 2

[0080] As described in Example 1, the preparation method was the same as that of Example 1, except that the width of the micro-textured graphite paper groove was 2 μm, the spacing was 3 μm, and the depth was 70 μm. A large number of defects existed in the micro-groove texture prepared by the post-treatment process of the cermet tool material through the steps of cutting - rough grinding - fine grinding - lapping - polishing, and there was almost no texture. The cermet tool material was prepared into a 3 mm × 4 mm × 30 mm ceramic spline through the steps of cutting - rough grinding - fine grinding - lapping - polishing, and its mechanical properties were measured as follows: hardness 16.66 GPa, fracture toughness 5.33 MPa·m 1 / 2 and flexural strength 586.12 MPa. Through the friction experiment, under the condition of a test force of 10 N, the friction coefficient was measured to be 0.65.

[0081] Comparative Example 3

[0082] As described in Example 1, the preparation method is the same as that of Example 1, except that a graphite indenter is used instead of micro-textured graphite paper. Compared with the preparation of micro-textured graphite paper, the preparation time of the micro-textured graphite indenter is greatly extended, the surface ablation is serious, and the micro-texture forming effect is poor after sintering and forming, without a complete micro-texture. The cermet tool material is processed through the steps of cutting - rough grinding - fine grinding - lapping - polishing to prepare a non-textured tool. The cermet tool material is processed into a 3 mm × 4 mm × 30 mm ceramic spline through the steps of cutting - rough grinding - fine grinding - lapping - polishing, and its mechanical properties are measured as follows: hardness 15.31 GPa, fracture toughness 4.85 MPa·m 1 / 2 , flexural strength 520.16 MPa.

[0083] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A surface in-situ self-generated micro-textured tool, characterized in that, It includes a tool substrate, and at least one surface of the tool substrate is provided with micro-textured graphite paper; the thickness of the graphite paper is 0.1 - 0.5 mm; The rake face of the in-situ self-generated micro-textured tool forms surface residual compressive stress; The preparation method of the surface in-situ self-generated micro-textured tool includes the following steps: S1. Prepare micro-textured graphite paper; S2. Place the micro-textured graphite paper and tool powder in a mold and sinter them to prepare a micro-textured tool blank; S3. Cut the micro-textured tool blank into a rough tool, and successively perform grinding and chamfering on the rough tool, and then polish it into shape; In step S1, the preparation process of the micro-textured graphite paper includes: designing the micro-texture morphology size on the tool surface, and using laser processing technology to prepare micro-textured graphite paper; In step S2, the mold is a graphite mold; the graphite mold includes an upper punch and a lower punch; When the micro-textured graphite paper and tool powder are placed in the mold, from bottom to top are the lower punch, micro-textured graphite paper, tool powder, micro-textured graphite paper, and upper punch; In step S1, the groove width of the micro-textured graphite paper is 20 - 300 μm; the spacing is 20 - 300 μm; the depth is 5 - 200 μm.

2. The surface in-situ self-generated micro-textured tool according to claim 1, wherein Both the upper and lower surfaces of the tool substrate are provided with micro-textured graphite paper; The tool substrate is a tool with a cemented carbide substrate.

3. The surface in-situ self-generated micro-textured tool according to claim 2, wherein The micro-texture is of a groove type; In the groove-type micro-texture, the average groove width is 20 - 300 μm; the average spacing is 20 - 300 μm; the average depth is 5 - 150 μm.

4. A preparation method of the surface in-situ self-generated micro-textured tool according to any one of claims 1-3, characterized in that, It includes the following steps: S1. Prepare micro-textured graphite paper; S2. Place the micro-textured graphite paper and tool powder in a mold and sinter them to prepare a micro-textured tool blank; S3. Cut the micro-textured tool blank into a rough tool, and successively perform grinding and chamfering on the rough tool, and then polish it into shape.

5. The preparation method according to claim 4, characterized in that, In step S1, the preparation process of the micro-textured graphite paper includes: designing the micro-texture morphology size on the tool surface, and using laser processing technology to prepare micro-textured graphite paper; In the laser processing technology, the laser processing speed is 2 mm / s - 800 mm / s, and the laser processing power is 5 - 80 W.

6. The preparation method according to claim 4, characterized in that, In step S2, the mold is a graphite mold; the graphite mold includes an upper punch and a lower punch; When the micro-textured graphite paper and tool powder are placed in the mold, from bottom to top are the lower punch, micro-textured graphite paper, tool powder, micro-textured graphite paper, and upper punch; The tool powder is a metal ceramic material composite powder; The micro-textured tool blank is in a disc shape.

7. The preparation method according to claim 4, characterized in that, In step S2, the sintering is sintering in a vacuum atmosphere; The sintering includes one of spark plasma sintering, hot pressing sintering, and hot isostatic pressing sintering; The sintering temperature is 1300 - 1500 °C, the holding time is 5 - 20 minutes, and the sintering pressure is 10 - 60 MPa.

8. The preparation method according to claim 4, characterized in that, In step S3, the cutting is by wire electrical discharge machining; It is necessary to ensure that the main and secondary cutting edges of each tool tip of the rough tool are parallel to the boundary of the square micro-texture unit, and the boundary is kept at a distance of 1 mm - 2 mm from the micro-texture.

9. The preparation method according to claim 4, characterized in that, In step S3, the upper and lower surfaces of the rough tool are micro-textured surfaces, and the remaining surfaces are non-micro-textured surfaces; Alternatively, in step S3, the grinding includes grinding the non-textured surface and the micro-textured surface of the tool blank respectively; the grinding includes rough grinding and finish grinding.

10. The preparation method according to claim 4, characterized in that, In step S3, the chamfering process is to chamfer the tool blank, and the chamfer radius is 0.5 - 1 mm.

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