High-entropy carbide ceramic-based nanocomposite cutting tool material and preparation method thereof

Abstract

The present application relates to the technical field of ceramic matrix composite, in particular to a high-strength and high-toughness high-entropy carbide ceramic matrix composite tool material and a preparation method thereof.The present application uses metal Ni as the metal binder phase of high-entropy carbide ceramic, uses nano-Al2O3 as the ceramic binder phase, and simultaneously introduces graphene as the toughening phase of high-entropy carbide ceramic, so as to realize the synergistic improvement of multiple performances such as hardness, bending strength and fracture toughness of high-entropy ceramic material.Through the multi-scale cross-dimension coupling and regulation of micron-level metal Ni, nano-level ceramic Al2O3 and two-dimensional graphene nanosheet, and by using a suitable spark plasma sintering process, the high-entropy carbide ceramic matrix composite material with optimal performance configuration is obtained.This material has potential application value in the field of tool preparation and application.

Description

Technical Field

[0001] This invention belongs to the field of carbide ceramic matrix composite technology, specifically a high-entropy carbide ceramic matrix nanocomposite cutting tool material and its preparation method. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] In the field of high-entropy ceramics, exploration of their structure and function mainly focuses on oxides, nitrides, carbides, and borides. Among these, high-entropy carbide ceramics have attracted considerable attention due to their outstanding properties. They possess excellent oxidation resistance, wear resistance, and radiation resistance, along with a high melting point, low thermal conductivity, and excellent hardness, elastic modulus, and chemical inertness. Therefore, high-entropy carbide ceramics have significant practical value in ultra-high temperature coating and thermal insulation materials for spacecraft and gas turbines, cutting tools, nuclear reactors, and jet engines, and are considered an ideal choice.

[0004] However, densification and toughening of high-entropy carbide ceramics have always been major challenges limiting their development. Generally, hardness and toughness are contradictory in traditional ceramic matrices; in high-entropy carbide ceramics, a trade-off between hardness and toughness is unavoidable, thus requiring advanced strategies to address this conflict. Due to the high melting point of carbide ceramics, traditional sintering methods such as vacuum sintering and hot pressing often fail to produce dense high-entropy ceramic materials in the absence of a binder phase. Furthermore, research on toughening in high-entropy ceramics still has gaps. It is currently unclear whether traditional ceramic toughening methods are applicable to high-entropy ceramic systems, hindering the widespread application and promotion of high-entropy ceramic materials. In conclusion, research on high-entropy carbide ceramics faces challenges in densification and toughening. Solving these problems will contribute to the development and application of high-entropy ceramic materials. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a high-density, high-strength, high-entropy carbide ceramic-based multi-scale multidimensional nanocomposite cutting tool material, and also provides a simple preparation method suitable for industrial production.

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

[0007] In a first aspect, the present invention provides a high-entropy carbide ceramic-based nanocomposite cutting tool material, comprising the following raw materials in weight percentages: 92.2–96.4 wt.% high-entropy carbide ceramic and nano-Al2O3.

[0008] 3–6 wt.%, Ni 0.5–1.5 wt.%, graphene 0.1–0.3 wt.%.

[0009] This invention employs metallic Ni as the metallic binder phase in high-entropy carbide ceramics, introduces nano-Al₂O₃ as the ceramic binder phase, and incorporates two-dimensional graphene as the strengthening phase to further optimize the material's hardness, flexural strength, and fracture toughness. By coupling the strengthening effects of micron-scale metallic Ni and nano-scale ceramic Al₂O₃, and inheriting the advantages of each dimension of two-dimensional graphene and Al₂O₃, the strengthening effects at different scales and dimensions are compensated. Through spark plasma sintering, a graphene-high-entropy carbide ceramic-based multi-scale multi-dimensional nanocomposite cutting tool material with precisely controllable binder phase content and optimal performance configuration is obtained. This material has potential application value in the field of cutting tool manufacturing and application.

[0010] In some embodiments, the high-entropy carbide ceramic is prepared from the following raw materials: NbC, ZrC, WC, TaC, and TiC, wherein the molar ratio of NbC, ZrC, WC, TaC, and TiC is 1-1.2:1-1.2:1-1.2:1-1.2:1-1.2:1-1.2.

[0011] In some embodiments, the particle size of NbC, ZrC, WC, TaC, and TiC is 0.4-0.5 μm.

[0012] In some embodiments, the Ni has a particle size of 0.5-0.6 μm.

[0013] In some embodiments, the particle size of the nano-Al2O3 is 100-120 nm.

[0014] A second aspect of the present invention provides a method for preparing a high-entropy carbide ceramic-based nanocomposite cutting tool material, comprising:

[0015] Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium. Under water bath ultrasonic conditions, five carbide powders were added in order of increasing content. After the addition was completed, a high-entropy carbide ceramic suspension was obtained under mechanical stirring and ultrasonic dispersion. The suspension was then further ultrasonically dispersed, ball-milled, and dried to obtain high-entropy carbide ceramic powder.

[0016] Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium. Ni, nano-Al2O3 and graphene were added in order of increasing content under water bath ultrasonic conditions. Under mechanical stirring and ultrasonic dispersion, a doped phase suspension was obtained.

[0017] The high-entropy carbide ceramic powder is mixed with the doped phase suspension and ultrasonically dispersed in a water bath to obtain a high-entropy carbide ceramic matrix composite powder suspension. The suspension is then ball-milled, dried, and sieved to obtain the high-entropy carbide ceramic matrix composite powder.

[0018] The high-entropy carbide ceramic matrix composite powder is pressed into shape in a mold and sintered to obtain a high-entropy carbide ceramic matrix nanocomposite cutting tool material.

[0019] In some embodiments, a carbide ceramic powder is added and ultrasonically dispersed in a water bath for 15-20 minutes with thorough stirring, and another carbide powder is added every 15-20 minutes.

[0020] In some embodiments, Ni metal powder is added and ultrasonically dispersed in a water bath for 15-20 minutes with thorough stirring. Nano Al2O3 ceramic powder is added every 15-20 minutes and ultrasonically dispersed and stirred thoroughly. Graphene is added every 15-20 minutes and ultrasonically dispersed and stirred thoroughly.

[0021] In some embodiments, the ball milling time is 24-32 hours.

[0022] In some embodiments, the sintering is performed using a spark plasma sintering process: the vacuum level is maintained at 1×10⁻⁶. -3 Below Pa, the temperature is increased to 1200-1300℃ at 86-90℃ / min, then increased to 1600-1700℃ at 100-110℃ / min, held for 10-15min, and then cooled to 700-800℃ at 100-110℃ / min, followed by furnace cooling. During the temperature rise from room temperature to 1600-1700℃, the pressure is maintained at 30-35MPa. During the holding period at 1600-1700℃, the pressure is maintained at 30-35MPa. During the cooling period to 700-800℃, the pressure is maintained at 11-12MPa.

[0023] More specifically, including:

[0024] (1) Preparation of high-entropy carbide ceramic powder

[0025] Five carbide powders (NbC, ZrC, WC, TaC, and TiC) were weighed in equimolar ratios. Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium. The five carbide powders were added sequentially from lowest to highest concentration. One carbide ceramic powder was added at a time, and the mixture was ultrasonically dispersed in a water bath for 15 minutes with thorough stirring. Another carbide powder was added every 15 minutes until all five powders were added, and the mixture was then ultrasonically dispersed and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a high-entropy carbide ceramic suspension was obtained, and ultrasonic dispersion was continued for 1 hour. Grinding balls were added at a specific ball-to-powder ratio, and the mixture was ball-milled for 24 hours. The powder was then dried in a vacuum drying oven and sieved to obtain the high-entropy carbide ceramic powder.

[0026] (2) Ingredients

[0027] The mass ratio is (95.85 wt.%) high-entropy ceramics - (3 wt.%) Al2O3 - (1 wt.%) Ni - (0.15 wt.%) graphene.

[0028] (3) Doped phase dispersion

[0029] Anhydrous ethanol was used as the dispersant, and polyethylene glycol and polyvinylpyrrolidone (PVP) at 1.0% of the relative mass of the nano-Al₂O₃ particles were added as the dispersion medium. Ni, nano-Al₂O₃, and graphene were added sequentially in ascending order of content. Ni metal powder was added and ultrasonically dispersed in a water bath for 15 min with thorough stirring. Nano-Al₂O₃ ceramic powder was added after 15 min, and the mixture was ultrasonically dispersed and stirred thoroughly. Graphene was added after 15 min, and the mixture was ultrasonically dispersed and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a doped phase suspension was obtained, and ultrasonic dispersion was continued for 1 h.

[0030] (4) Mixing

[0031] According to the proportion in step (2), the high-entropy carbide ceramic powder is mixed with the doped phase suspension obtained in step (3), and ultrasonically dispersed in a water bath for 15 minutes to obtain a high-entropy carbide ceramic matrix composite powder suspension. Grinding balls are added at a certain ball-to-material ratio, and the mixture is ball-milled for 24 hours. Then, it is dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic matrix composite powder.

[0032] (5) Pressing and sintering

[0033] Calculate the required weight of high-entropy carbide ceramic matrix composite powder based on the mold size, separate the mold and powder contact area with graphite paper, and load the powder; employ spark plasma sintering process: maintain a vacuum level of 1×10⁻⁶. -3Below Pa, the temperature is increased to 1200℃ at 86℃ / min, then increased to 1600℃ at 100℃ / min, held for 10 min, and then cooled to 800℃ at 100℃ / min, followed by furnace cooling. During the period from room temperature to 1600℃, the pressure is maintained at 30 MPa. During the holding period at 1600℃, the pressure is maintained at 30 MPa. During the cooling period from 1600℃ to 800℃, the pressure is maintained at 11 MPa.

[0034] From the beginning of the sintering process to the end, a high-density, high-strength, high-entropy carbide ceramic-based multi-scale nanocomposite cutting tool material can be obtained.

[0035] Beneficial effects of the present invention

[0036] (1) This invention achieves multi-scale integration by coupling the strengthening effects of micron-scale metallic Ni and nano-scale ceramic Al2O3, and inherits the advantages of two-dimensional graphene and Al2O3 in various dimensions. This compensates for the strengthening effects at different scales and dimensions, enabling performance-driven ceramic tool material design.

[0037] (2) In this invention, metal Ni is introduced as the metal binder phase of high-entropy carbide ceramics, and nano-Al2O3 is introduced as the ceramic binder phase of high-entropy carbide ceramics, which can realize low-temperature controllable sintering of high-entropy ceramics.

[0038] (3) The present invention uses spark plasma sintering technology, which has a short sintering time and sintering temperature, and can achieve high densification while suppressing the growth of high entropy carbide ceramic grains.

[0039] (4) From a production technology perspective, a technology is provided that enables the industrial production of high-density, high-strength, and high-entropy ceramic cutting tool materials.

[0040] (5) The preparation method of the present invention is simple, practical and easy to promote. Attached Figure Description

[0041] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. Exemplary embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0042] Figure 1 This is a multi-scale, cross-dimensional design diagram for high-entropy carbide ceramic matrix composites. Detailed Implementation

[0043] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0044] Terminology Explanation:

[0045] Al2O3 refers to aluminum oxide.

[0046] Ni refers to nickel.

[0047] NbC refers to niobium carbide.

[0048] ZrC refers to zirconium carbide.

[0049] WC refers to tungsten carbide.

[0050] TaC refers to tantalum carbide.

[0051] TiC refers to titanium carbide.

[0052] The present invention will be further described in detail below with reference to specific embodiments. It should be noted that the specific embodiments are explanations of the present invention and not limitations thereof.

[0053] In the following embodiments, the bending strength, Vickers hardness, and fracture toughness of the tool material were all tested using methods commonly used in the industry.

[0054] Example 1

[0055] (1) Five carbide ceramic powders (0.4 μm NbC, ZrC, WC, TaC, and TiC) were used as raw materials and prepared in equimolar ratios. Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium (the total amount of polyethylene glycol and polyvinylpyrrolidone was 1.5% of the carbide mass, and the mass ratio of the two was 2:3). The five carbide powders were added in order of increasing content. One carbide ceramic powder was added and ultrasonically dispersed in a water bath for 15 min with thorough stirring. Another carbide powder was added every 15 min until all five powders were added and ultrasonically dispersed and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a high-entropy carbide ceramic suspension was obtained and ultrasonically dispersed for another 1 h. Grinding balls were added at a certain ball-to-material ratio, and the mixture was ball-milled for 24 h. Then, it was dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic powder.

[0056] (2) Using the high-entropy carbide ceramic and 0.5μm nickel (Ni) from step (1) as raw materials, the high-entropy ceramic and 0.5μm nickel (Ni) are mixed in a mass ratio of (99wt.%) high-entropy ceramic and (1wt.%) Ni.

[0057] (3) Anhydrous ethanol was used as a dispersant, and polyethylene glycol and polyvinylpyrrolidone (polyethylene glycol and polyvinylpyrrolidone in a mass ratio of 2:3) were added relative to the mass of Ni particles. Ni metal powder was added and ultrasonically dispersed in a water bath for 15 min and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a doped phase suspension was obtained and ultrasonic dispersion was continued for 1 h.

[0058] (4) According to the ratio in step (2), the high-entropy carbide ceramic powder is mixed with the doped phase suspension obtained in step (3), and ultrasonically dispersed in a water bath for 15 minutes to obtain a high-entropy carbide ceramic matrix composite powder suspension. Grinding balls are added at a certain ball-to-material ratio, and the mixture is ball-milled for 24 hours. Then it is dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic matrix composite powder.

[0059] (5) Using spark plasma sintering process: vacuum degree maintained at 1×10 -3 Below Pa, the temperature is increased to 1200℃ at 86℃ / min, then increased to 1600℃ at 100℃ / min, held for 10 min, and then cooled to 800℃ at 100℃ / min, followed by furnace cooling. During the period from room temperature to 1600℃, the pressure is maintained at 30 MPa. During the holding period at 1600℃, the pressure is maintained at 30 MPa. During the cooling period from 1600℃ to 800℃, the pressure is maintained at 11 MPa.

[0060] After the sintering process is completed, a high-density, high-strength, and high-toughness high-entropy carbide ceramic-based multi-scale multidimensional nanocomposite cutting tool material can be obtained. Its mechanical properties are: bending strength 560.42 MPa, Vickers hardness HV. 0.5 17.69 GPa, fracture toughness 6.47 MPa·m 1 / 2 .

[0061] Example 2

[0062] (1) Five carbide ceramic powders (0.4 μm NbC, ZrC, WC, TaC, and TiC) were used as raw materials and prepared in equimolar ratios. Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium (the total amount of polyethylene glycol and polyvinylpyrrolidone was 1.5% of the carbide mass, and the mass ratio of the two was 2:3). The five carbide powders were added in order of increasing content. One carbide ceramic powder was added and ultrasonically dispersed in a water bath for 15 min with thorough stirring. Another carbide powder was added every 15 min until all five powders were added and ultrasonically dispersed and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a high-entropy carbide ceramic suspension was obtained and ultrasonically dispersed for another 1 h. Grinding balls were added at a certain ball-to-material ratio, and the mixture was ball-milled for 24 h. Then, it was dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic powder.

[0063] (2) Using the high-entropy carbide ceramic and 100nm alumina (Al2O3) from step (1) as raw materials, according to (97wt.%)

[0064] High-entropy ceramics - (3wt.%)Al2O3 mass ratio.

[0065] (3) Anhydrous ethanol was used as a dispersant, and polyethylene glycol and polyvinylpyrrolidone (polyethylene glycol and polyvinylpyrrolidone) at a relative mass of 1.0% of the nano-Al2O3 particles were added as a dispersion medium (mass ratio of polyethylene glycol to polyvinylpyrrolidone was 2:3). Nano-Al2O3 ceramic powder was added and ultrasonically dispersed in a water bath for 15 min with thorough stirring. Under mechanical stirring and ultrasonic dispersion, a doped phase suspension was obtained, and ultrasonic dispersion was continued for 1 h.

[0066] (4) According to the ratio in step (2), the high-entropy carbide ceramic powder is mixed with the doped phase suspension obtained in step (3), and ultrasonically dispersed in a water bath for 15 minutes to obtain a high-entropy carbide ceramic matrix composite powder suspension. Grinding balls are added at a certain ball-to-material ratio, and the mixture is ball-milled for 24 hours. Then it is dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic matrix composite powder.

[0067] (5) Using spark plasma sintering process: vacuum degree maintained at 1×10 -3 Below Pa, the temperature is increased to 1200℃ at 86℃ / min, then increased to 1600℃ at 100℃ / min, held for 10 min, and then cooled to 800℃ at 100℃ / min, followed by furnace cooling. During the period from room temperature to 1600℃, the pressure is maintained at 30 MPa. During the holding period at 1600℃, the pressure is maintained at 30 MPa. During the cooling period from 1600℃ to 800℃, the pressure is maintained at 11 MPa.

[0068] After the sintering process is completed, a high-density, high-strength, and high-toughness high-entropy carbide ceramic-based multi-scale multidimensional nanocomposite cutting tool material can be obtained. Its mechanical properties are: bending strength 592.15 MPa, Vickers hardness HV. 0.5 23.63 GPa, fracture toughness 6.06 MPa·m 1 / 2 .

[0069] Example 3

[0070] (1) Five carbide ceramic powders (0.4 μm NbC, ZrC, WC, TaC, and TiC) were used as raw materials and prepared in equimolar ratios. Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium (the total amount of polyethylene glycol and polyvinylpyrrolidone was 1.5% of the carbide mass, and the mass ratio of the two was 2:3). The five carbide powders were added in order of increasing content. One carbide ceramic powder was added and ultrasonically dispersed in a water bath for 15 min with thorough stirring. Another carbide powder was added every 15 min until all five powders were added and ultrasonically dispersed and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a high-entropy carbide ceramic suspension was obtained and ultrasonically dispersed for another 1 h. Grinding balls were added at a certain ball-to-material ratio, and the mixture was ball-milled for 24 h. Then, it was dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic powder.

[0071] (2) Using the high-entropy carbide ceramic, 0.5μm nickel (Ni) and 100nm alumina (Al2O3) from step (1) as raw materials, the high-entropy ceramic, 0.5μm nickel (Ni) and 100nm alumina (Al2O3) are mixed in a mass ratio of (96wt.%) high-entropy ceramic - (3wt.%) Al2O3 - (1wt.%) Ni.

[0072] (3) Anhydrous ethanol was used as the dispersant, and polyethylene glycol and polyvinylpyrrolidone (polyethylene glycol to polyvinylpyrrolidone) at a relative mass of 1.0% of the nano-Al2O3 particles were added as the dispersion medium (the mass ratio of polyethylene glycol to polyvinylpyrrolidone was 2:3). Metallic Ni, nano-Al2O3, and graphene were added sequentially from low to high content. Ni metal powder was added and ultrasonically dispersed in a water bath for 15 min with thorough stirring. Nano-Al2O3 ceramic powder was added every 15 min, and then ultrasonically dispersed and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a doped phase suspension was obtained, and ultrasonic dispersion was continued for 1 h.

[0073] (4) According to the ratio in step (2), the high-entropy carbide ceramic powder is mixed with the doped phase suspension obtained in step (3), and ultrasonically dispersed in a water bath for 15 minutes to obtain a high-entropy carbide ceramic matrix composite powder suspension. Grinding balls are added at a certain ball-to-material ratio, and the mixture is ball-milled for 24 hours. Then it is dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic matrix composite powder.

[0074] (5) Using spark plasma sintering process: vacuum degree maintained at 1×10 -3 Below Pa, the temperature is increased to 1200℃ at 86℃ / min, then increased to 1600℃ at 100℃ / min, held for 10 min, and then cooled to 800℃ at 100℃ / min, followed by furnace cooling. During the period from room temperature to 1600℃, the pressure is maintained at 30 MPa. During the holding period at 1600℃, the pressure is maintained at 30 MPa. During the cooling period from 1600℃ to 800℃, the pressure is maintained at 11 MPa.

[0075] After the sintering process is completed, a high-density, high-strength, and high-toughness high-entropy carbide ceramic-based multi-scale multidimensional nanocomposite cutting tool material can be obtained. Its mechanical properties are: bending strength 524.35 MPa, Vickers hardness HV. 05 19.77 GPa, fracture toughness 6.95 MPa·m 1 / 2 .

[0076] Example 4

[0077] (1) Five carbide ceramic powders (0.4 μm NbC, ZrC, WC, TaC, and TiC) were used as raw materials and prepared in equimolar ratios. Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium (the total amount of polyethylene glycol and polyvinylpyrrolidone was 1.5% of the carbide mass, and the mass ratio of the two was 2:3). The five carbide powders were added in order of increasing content. One carbide ceramic powder was added and ultrasonically dispersed in a water bath for 15 min with thorough stirring. Another carbide powder was added every 15 min until all five powders were added and ultrasonically dispersed and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a high-entropy carbide ceramic suspension was obtained and ultrasonically dispersed for another 1 h. Grinding balls were added at a certain ball-to-material ratio, and the mixture was ball-milled for 24 h. Then, it was dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic powder.

[0078] (2) Using the high-entropy carbide ceramic, 0.5μm nickel (Ni), 100nm alumina (Al2O3), and graphene from step (1) as raw materials, the mixture was prepared in the following order: (95.85wt.%) high-entropy ceramic - (3wt.%) Al2O3 - (1wt.%) Ni -

[0079] (0.15wt.%) Graphene mass ratio.

[0080] (3) Anhydrous ethanol was used as the dispersant, and polyethylene glycol and polyvinylpyrrolidone (polyethylene glycol to polyvinylpyrrolidone mass ratio of 2:3) were added as the dispersion medium at a relative mass of 1.0% of the nano-Al2O3 particles. Ni, nano-Al2O3, and graphene were added in order of increasing content. Ni metal powder was added and ultrasonically dispersed in a water bath for 15 min with thorough stirring. Nano-Al2O3 ceramic powder was added after 15 min and ultrasonically dispersed and stirred thoroughly. Graphene was added after 15 min and ultrasonically dispersed and stirred thoroughly. Under mechanical stirring and ultrasonic dispersion, a doped phase suspension was obtained, and ultrasonic dispersion was continued for 1 h.

[0081] (4) According to the ratio in step (2), the high-entropy carbide ceramic powder is mixed with the doped phase suspension obtained in step (3), and ultrasonically dispersed in a water bath for 15 minutes to obtain a high-entropy carbide ceramic matrix composite powder suspension. Grinding balls are added at a certain ball-to-material ratio, and the mixture is ball-milled for 24 hours. Then it is dried in a vacuum drying oven and sieved to obtain well-dispersed high-entropy carbide ceramic matrix composite powder.

[0082] (5) Using spark plasma sintering process: vacuum degree maintained at 1×10 -3Below Pa, the temperature is increased to 1200℃ at 86℃ / min, then increased to 1600℃ at 100℃ / min, held for 10 min, and then cooled to 800℃ at 100℃ / min, followed by furnace cooling. During the period from room temperature to 1600℃, the pressure is maintained at 30 MPa. During the holding period at 1600℃, the pressure is maintained at 30 MPa. During the cooling period from 1600℃ to 800℃, the pressure is maintained at 11 MPa.

[0083] After the sintering process is completed, a high-density, high-strength, and high-toughness high-entropy carbide ceramic-based multi-scale multidimensional nanocomposite cutting tool material can be obtained. Its mechanical properties are: bending strength 572.40 MPa, Vickers hardness HV. 0.5 21.73 GPa, fracture toughness 7.65 MPa·m 1 / 2 .

[0084] Comparative Example 1

[0085] The difference from Example 4 is that Fe is used instead of Ni. Its mechanical properties are: flexural strength 497.13 MPa, Vickers hardness HV. 0.5 19.92 GPa, fracture toughness 6.21 MPa·m 1 / 2 .

[0086] Comparative Example 2

[0087] The difference from Example 4 is that micron-sized Al2O3 is used instead of nano-sized Al2O3. Its mechanical properties are: flexural strength 514.61 MPa, Vickers hardness HV. 0.5 20.46 GPa, fracture toughness 5.73 MPa·m 1 / 2 .

[0088] As can be seen from the comparison between Example 4 and Comparative Example 1, compared with Fe, using Ni as the metal binder phase of high-entropy carbide ceramics can be coupled with the strengthening and toughening effect of nanoscale ceramic Al2O3, thereby better improving the strength and toughness of the tool material.

[0089] As can be seen from the comparison between Example 4 and Comparative Example 2, nano Al2O3 has a better effect on improving the strength and toughness of tool materials compared with micron Al2O3.

[0090] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-entropy carbide ceramic-based nanocomposite cutting tool material, characterized in that, It is composed of the following raw materials in weight percentage: high-entropy carbide ceramic 92.2~96.4 wt.%, nano-Al2O3 3~6 wt.%, Ni 0.5~1.5 wt.%, and graphene 0.1~0.3 wt.%; The high-entropy carbide ceramic is prepared from the following raw materials: NbC, ZrC, WC, TaC, and TiC, wherein the molar ratio of NbC, ZrC, WC, TaC, and TiC is 1-1.2:1-1.2:1-1.2:1-1.2:1-1.2; The particle size of the nano-Al2O3 is 100-120 nm.

2. The high-entropy carbide ceramic-based nanocomposite cutting tool material as described in claim 1, characterized in that, The particle size of NbC, ZrC, WC, TaC, and TiC is 0.4-0.5 μm.

3. The high-entropy carbide ceramic-based nanocomposite cutting tool material as described in claim 1, characterized in that, The Ni has a particle size of 0.5-0.6 μm.

4. A method for preparing the high-entropy carbide ceramic-based nanocomposite cutting tool material as described in claim 1, characterized in that, include: Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium. Under water bath ultrasonic conditions, five carbide powders were added in order of increasing content. After the addition was completed, a high-entropy carbide ceramic suspension was obtained under mechanical stirring and ultrasonic dispersion. The suspension was then further ultrasonically dispersed, ball-milled, and dried to obtain high-entropy carbide ceramic powder. Anhydrous ethanol was used as the dispersion solvent, and polyethylene glycol and polyvinylpyrrolidone were used as the dispersion medium. Ni, nano-Al2O3 and graphene were added in order of increasing content under water bath ultrasonic conditions. Under mechanical stirring and ultrasonic dispersion, a doped phase suspension was obtained. The high-entropy carbide ceramic powder is mixed with the doped phase suspension and ultrasonically dispersed in a water bath to obtain a high-entropy carbide ceramic matrix composite powder suspension. The suspension is then ball-milled, dried, and sieved to obtain the high-entropy carbide ceramic matrix composite powder. The high-entropy carbide ceramic matrix composite powder is pressed into shape in a mold and sintered to obtain a high-entropy carbide ceramic matrix nanocomposite cutting tool material. The high-entropy carbide ceramic is prepared from the following raw materials: NbC, ZrC, WC, TaC, and TiC, wherein the molar ratio of NbC, ZrC, WC, TaC, and TiC is 1-1.2:1-1.2:1-1.2:1-1.2:1-1.2; The particle size of the nano-Al2O3 is 100-120 nm.

5. The method for preparing the high-entropy carbide ceramic-based nanocomposite cutting tool material as described in claim 4, characterized in that, Add one type of carbide ceramic powder and ultrasonically disperse it in a water bath for 15-20 minutes while stirring thoroughly. Add another type of carbide powder every 15-20 minutes.

6. The method for preparing the high-entropy carbide ceramic-based nanocomposite cutting tool material as described in claim 4, characterized in that, Add Ni metal powder and ultrasonically disperse it in a water bath for 15-20 minutes while stirring thoroughly. Add nano Al2O3 ceramic powder every 15-20 minutes and ultrasonically disperse and stir thoroughly. Add graphene every 15-20 minutes and ultrasonically disperse and stir thoroughly.

7. The method for preparing the high-entropy carbide ceramic-based nanocomposite cutting tool material as described in claim 4, characterized in that, The ball milling time is 24-32 hours.

8. The method for preparing the high-entropy carbide ceramic-based nanocomposite cutting tool material as described in claim 4, characterized in that, The sintering process employs spark plasma sintering, with the vacuum level maintained at 1×10⁻⁶. -3 Below Pa, the temperature is increased to 1200-1300℃ at 86-90℃ / min, then increased to 1600-1700℃ at 100-110℃ / min, held for 10-15min, and then cooled to 700-800℃ at 100-110℃ / min, followed by furnace cooling. During the temperature rise from room temperature to 1600-1700℃, the pressure is maintained at 30-35MPa. During the holding period at 1600-1700℃, the pressure is maintained at 30-35MPa. During the cooling period to 700-800℃, the pressure is maintained at 11-12MPa.

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