Endophytic carbide enhanced metal ceramic material and design method thereof

Abstract

The invention provides an endogenous carbide enhanced metal ceramic material and a design method thereof. The design method comprises the following steps: calculating and predicting the mechanical properties of a ceramic phase, endogenous carbide and friction oxide in the metal ceramic material by using a first principle; based on the mechanical properties, setting screening standards of ceramic phases, endogenous carbides and friction oxides in the metal ceramic material, obtaining a target metal ceramic system, and determining the types of composition elements; in combination with phase diagram calculation, component intervals formed by different phases in the target metal ceramic system and a sintering window of the metal ceramic material are determined; the metal ceramic material and the preparation method thereof are designed based on component element types, component intervals and sintering windows. Through combination of first principle calculation and phase diagram calculation, the first principle calculation and the phase diagram calculation synergistically form design and prediction capability from a micromechanism to a macroscopic process, and the metal ceramic material with excellent strength, fracture toughness, high temperature resistance and high wear resistance is obtained through design.

Description

Technical Field

[0001] This invention belongs to the field of metal-ceramic materials technology, specifically relating to an endogenous carbide-reinforced metal-ceramic material and its design method. Background Technology

[0002] Ceramic materials (including cemented carbides) combine the high toughness and ductility of metals with the high melting point and wear resistance of ceramics, making them widely used in key engineering fields such as oil drilling, tunnel boring machines, and metal processing. Examples include drill bits and cutting tools, considered the "teeth of industry," and they are included in the national strategic new materials category. Traditional cemented carbides (WC-Co) have a history of nearly a century. Although performance optimization has been achieved through composition control and gradient structure construction, many problems remain, such as poor oxidation and corrosion resistance, making it difficult to meet the needs of modern industrial development. While Ti(C,N)-based cermets possess advantages such as high hardness and high oxidation resistance, their fracture toughness is insufficient (6-9 MPa∙m). 1 / 2 Furthermore, its high-temperature performance is insufficient to meet the requirements of dry, high-speed processing techniques. Therefore, there is an urgent need to develop new metal-ceramic materials with high strength, toughness, wear resistance, and high temperature resistance to support the rapid development of resource drilling, metal processing, and precision component industries.

[0003] Since their introduction in 2004, high-entropy alloys have rapidly become a research hotspot in materials science due to their unique high-entropy effect and hysteresis diffusion effect, exhibiting excellent mechanical properties, oxidation resistance, and high-temperature stability. Researchers have further developed high-entropy ceramic materials based on high-entropy alloys. This new material not only inherits the excellent properties of high-entropy alloys but also breaks through the performance limitations of traditional ceramics, showing broad application prospects in catalysis, thermal protection, high-temperature structural components, and precision machining, becoming a revolutionary direction for high-performance ceramic materials.

[0004] In recent years, research methods combining first-principles calculations and phase diagram calculations (CALPHAD) have played an increasingly important role in the development of cermets. First-principles calculations can accurately predict interfacial bonding strength, stability, and key thermodynamic properties at the atomic and electronic scale, revealing the physical essence behind the properties. For example, the invention patent with publication number CN116959632A discloses a machine learning design method for ultra-hard transition metal carbide high-entropy ceramics, including: collecting historical experimental data and first-principles simulation calculation information on the hardness of high-entropy transition metal carbide ceramics; calculating input feature descriptors based on the elemental composition ratio and inherent properties of the high-entropy ceramics to construct an initial dataset; performing feature engineering on the initial dataset, deleting redundant features, and standardizing the optimized dataset to obtain a high-entropy ceramic hardness prediction training set and a test set; training a selected machine learning model using the training set, and optimizing the model's hyperparameters through ten-fold cross-validation; evaluating and screening the trained machine learning models using the test set, and selecting the model with the best performance; establishing a hardness prediction dataset for high-entropy transition metal carbide ceramics in an unknown composition space based on the optimal model, and designing a novel ultra-hard transition metal carbide high-entropy ceramic by combining feature analysis.

[0005] Phase diagram calculations, based on thermodynamic principles, depict the phase equilibrium relationships of materials, enabling precise composition selection, determination of sintering process windows, and prediction of equilibrium phase composition. Together, these two methods constitute a capability for designing and predicting from microscopic mechanisms to macroscopic processes. This integrated computational materials engineering approach fundamentally changes the traditional "trial and error" R&D model, enabling rational design and efficient development of metal-ceramic materials, significantly shortening the R&D cycle and reducing costs. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides an endogenous carbide-reinforced metal-ceramic material and its design method. Combining first-principles calculations and phase diagram calculations, the two work together to form a design and prediction capability from microscopic mechanism to macroscopic process, resulting in a metal-ceramic material with excellent strength, fracture toughness, high temperature resistance, and high wear resistance.

[0007] The technical solution adopted by this application to solve the above problems is as follows: This invention provides a method for designing endogenous carbide-reinforced metal-ceramic materials, comprising the following steps: (1) Predict the mechanical properties of ceramic phase, endogenous carbides, and tribological oxides in cermet materials using first-principles calculations; (2) Based on mechanical properties, screening criteria were set to screen out ceramic phases, endogenous carbides, and tribooxides to obtain the target metal ceramic system and determine the types of constituent elements; (3) Combine phase diagram calculations to determine the composition range of different phases in the target metal-ceramic system and the sintering window of the metal-ceramic material; (4) Based on the types of constituent elements determined in step (2) and the composition range and sintering window determined in step (3), metal ceramic materials and their preparation methods are designed.

[0008] This invention utilizes first-principles calculations at the atomic and electronic scale to accurately predict interfacial bonding strength, stability, and key thermodynamic properties, revealing the physical essence behind these properties. Phase diagram calculations, based on thermodynamic principles, depict the phase equilibrium relationships of materials, enabling precise composition selection, determination of sintering process windows, and prediction of equilibrium phase composition. Together, these two methods constitute a comprehensive capability for designing and predicting processes from microscopic mechanisms to macroscopic processes.

[0009] Preferably, in step (1), the mechanical properties predicted by the first-principles calculation method include: obtaining the phase cell parameters of the ceramic phase, endogenous carbides, and tribooxides in the cermet material, calculating the intrinsic elastic constant matrix, and obtaining the bulk modulus, shear modulus, and hardness.

[0010] Preferably, in step (2), the screening criteria are set to screen out ceramic phase, endogenous carbide, and friction oxide, including: calculating the ratio of bulk modulus to shear modulus and Cauchy pressure based on bulk modulus, shear modulus, and hardness, and setting screening criteria to screen out ceramic phase, endogenous carbide, and friction oxide; The screening criteria for both the ceramic phase and the friction oxide prioritized hardness; specifically, the screening criterion for the ceramic phase was a hardness greater than 30 GPa, and the screening criterion for the friction oxide was a hardness greater than 5 GPa. The screening criteria for endogenous carbides are a volume modulus to shear modulus ratio greater than 1.5 or a Cauchy pressure greater than 0.

[0011] This invention selects phases exhibiting both high hardness and high toughness by combining the ratio of bulk modulus to shear modulus and Cauchy pressure, and then screens for elemental types to determine the target metal-ceramic system. The higher the ratio of bulk modulus to shear modulus and the Cauchy pressure, the better the phase toughness.

[0012] On the other hand, the present invention also provides a metal-ceramic material, which, based on the total mass of the metal-ceramic material, includes 70-90 wt% high-entropy ceramic particles and the balance being a metal binder phase.

[0013] More preferably, it comprises 80-90 wt% high-entropy ceramic particles.

[0014] Preferably, the high-entropy ceramic particles are carbides or carbonitrides formed by any five or six elements selected from Ti, Nb, W, Mo, Ta, V, Zr, and Hf, including at least one of Mo and W.

[0015] In high-entropy ceramic particles, metallic elements such as W, Mo, Ta, and Nb can improve the mechanical properties of (Ti,Me) and (C,N) ceramic particles, where Me refers to metallic elements. W and Ta can improve toughness; Mo can improve the wettability of ceramic particles with metals during sintering, slightly increasing fracture toughness; Nb and Ta can effectively inhibit the growth of WC and Ti(C,N) particles, which is beneficial to improving the bending strength and thermal shock resistance of the material.

[0016] Preferably, the high-entropy ceramic particles contain ≥95% single-phase high-entropy ceramic and <5% other ceramic.

[0017] More preferably, the atomic ratio of Mo or W in the high-entropy ceramic particles is ≥10%.

[0018] Preferably, the high-entropy ceramic particles have a particle size of 0.5-10 μm. More preferably, the high-entropy ceramic particles have a particle size of 0.5-5 μm.

[0019] Preferably, the metal binder phase includes at least one of Co and Ni.

[0020] Preferably, the particle size of the metal binder phase is 0.5-30 μm. More preferably, the particle size of the metal binder phase is 0.5-5 μm.

[0021] Preferably, the metal-ceramic material has a hardness ≥1500 HV30 and a fracture toughness ≥9 MPa∙m at room temperature. 1 / 2 Abrasive wear rate at room temperature ≤7×10 -7 mm 3 / (N∙m), abrasive wear rate at 600℃ ≤1×10 -4 mm 3 / (N∙m).

[0022] On the other hand, the present invention also provides a method for preparing endogenous carbide-reinforced metal-ceramic materials, which involves uniformly mixing the high-entropy ceramic particles and the metal binder phase using a wet ball milling method, and then preparing the metal-ceramic material by rapid negative pressure sintering. The method specifically includes the following steps: (1) Based on the total weight, weigh the high-entropy ceramic particle raw material, metal powder raw material and forming agent to obtain the precursor powder, disperse it in the solvent and ball mill it evenly; (2) After the precursor powder is dried and sieved, it is pressed into shape and then sintered under a negative pressure in an inert atmosphere to obtain a metal ceramic material.

[0023] This invention rapidly sintersects mixed metal-ceramic powders into shape using rapid negative pressure sintering. The process is simple, and the heating and holding time is short, which can inhibit the growth of grains and endogenous compounds that cause performance degradation, accelerate production efficiency, and achieve large-scale rapid sintering.

[0024] Preferably, in step (1), the molding agent is paraffin wax; based on the total mass of the high-entropy ceramic particle raw material and the metal powder raw material, the proportion of the molding agent is 1-5 wt%.

[0025] Preferably, the solvent is anhydrous ethanol.

[0026] Dispersing the weighed precursor powder in anhydrous ethanol not only facilitates material dispersion but also effectively prevents cold welding and agglomeration.

[0027] Preferably, in step (1) ball milling, the mass ratio of grinding balls to precursor powder is 3-10:1, the ball milling speed is 50-300 r / min, and the ball milling time is 4-12 h.

[0028] Preferably, in step (2), the dried precursor powder is sieved sequentially using 40-mesh and 60-mesh sieves.

[0029] Multiple sieving processes can yield precursor powder with uniform particle size, which facilitates subsequent pressing and molding.

[0030] Preferably, the inert atmosphere described in step (2) is argon. By using argon for protection, oxidation and nitriding of high-entropy ceramic particles and metal binder phases are avoided.

[0031] Preferably, the rapid negative pressure sintering in step (2) includes: placing the pressed precursor powder into a sintering furnace, heating it to a first temperature and holding it at that temperature to remove wax; after removing wax, heating it to a second temperature and holding it at that temperature for sintering; after sintering, introducing an inert atmosphere to cool it to a third temperature; and then water cooling to obtain a metal ceramic material.

[0032] Preferably, the total sintering time in the sintering furnace is ≤4.5 h.

[0033] Preferably, the first temperature is 500℃, the corresponding holding time is 30 min, and the heating time is ≤2.5 h.

[0034] Preferably, the second temperature is 1400℃-1500℃, and the corresponding heat preservation time is ≤2 h; wherein the time above 1200℃ is ≤2 h.

[0035] Preferably, the third temperature is 1000℃ and the cooling time is ≤1 h.

[0036] By setting the above-mentioned rapid sintering time, sintering at a shorter high temperature can effectively prevent the growth of endogenous carbides.

[0037] Preferably, the sintering process is vacuum negative pressure sintering, wherein the furnace pressure during dewaxing is 0.5-20 kPa, and the furnace pressure after dewaxing is 2-20 kPa.

[0038] Preferably, M is generated in situ during sintering. x Type C compounds, wherein M is at least one of Ti, Nb, W, Mo, Ta, V, Zr, Co, and Ni, and X = 2-6.

[0039] More preferably, M is generated in situ during sintering. x Type C compounds are at least one of MoCoC, WCoC, (Mo,W)CoC, MoNiC, WNiC, and (Mo,W)NiC.

[0040] During sintering, MoCoC, WCoC, (Mo,W)CoC, or MoNiC, WNiC, (Mo,W)NiC compounds are formed. These endogenous compounds have a face-centered cubic structure and possess advantages such as high hardness, high thermal stability, and excellent interfacial bonding with the ceramic / metal matrix. Therefore, in this type of cermet material, in addition to the traditional ceramic hard phase and metal binder phase, the aforementioned hard carbide phase also exists. These endogenous carbides have hardness values ​​between the ceramic and metal phases and also possess a certain degree of toughness, which can act as endogenous reinforcements to significantly improve the hardness of the prepared cermet material. Since these endogenous reinforcements are uniformly dispersed in the matrix material, they can support and protect the matrix during friction, significantly improving the friction resistance of the cermet material at both room temperature and high temperature. In addition, the formation of these endogenous reinforcements originates from element diffusion between ceramic particles and the metal binder phase, and their location at the interface between ceramic particles and the metal binder phase can strengthen the ceramic / metal interfacial bonding and improve the fracture toughness of the material.

[0041] Compared with the prior art, the present invention has the following beneficial effects: 1. The metal-ceramic material design method of this application allows for targeted material design through first-principles calculations, enabling element selection based on performance requirements. Simultaneously, phase diagram calculations are used to select appropriate element contents and sintering temperatures, reducing trial-and-error costs and accelerating the development of metal-ceramic materials.

[0042] 2. The metal-ceramic material designed in this application uses high-entropy ceramic particles to replace traditional ceramic materials. Specific element combinations generate endogenous carbides as reinforcement, and high-performance friction products are generated on the friction surface. This gives the metal-ceramic material excellent strength, fracture toughness, high temperature resistance, and high wear resistance. At room temperature, its hardness is ≥1500 HV30, and its fracture toughness is ≥9 MPa∙m. 1 / 2 Abrasive wear rate at room temperature ≤7×10 -7 mm 3 / (N∙m), abrasive wear rate at 600℃ ≤1×10 -4 mm 3 / (N∙m).

[0043] 3. The metal-ceramic material preparation method of this application adopts a low-threshold negative pressure sintering technology to accelerate the heating and cooling process, shorten the holding time, simplify the preparation process, speed up the production cycle, reduce the production cost, and facilitate its mass production. Attached Figure Description

[0044] Figure 1 A flowchart illustrating the design process of the high-strength, high-toughness, and high-wear-resistant metal-ceramic material provided by this invention.

[0045] Figure 2 The phase diagram calculation results for the metal-ceramic material in Example 1 of this invention are shown.

[0046] Figure 3 This is a scanning electron microscope image of the metal-ceramic material in Embodiment 1 of the present invention.

[0047] Figure 4 This is a TEM-EDS image of the endogenous carbide MoWCoC reinforcement in the metal-ceramic composite material of Example 1 of the present invention.

[0048] Figure 5 The results of calculation and testing of hardness, elastic modulus, bulk modulus / shear modulus, and Cauchy pressure of the ceramic particles, binder phase, endogenous carbides, and friction products of the metal ceramic materials in Example 1 and the comparative example of the present invention are presented.

[0049] Figure 6 This is a scanning electron microscope image of the friction surface of the metal-ceramic material at 600°C in Example 1 of the present invention.

[0050] Figure 7 This is a scanning electron microscope image of the friction surface of the metal-ceramic material at 600℃ in Comparative Example 1 of the present invention. Detailed Implementation

[0051] The specific implementation methods of this application will be further described in detail below with reference to the accompanying drawings and embodiments. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0052] The specific implementation methods of this application will be further described in detail below with reference to the accompanying drawings and embodiments.

[0053] Example 1 The specific implementation methods of this application will be further described in detail below with reference to the accompanying drawings and embodiments. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0054] The specific implementation methods of this application will be further described in detail below with reference to the accompanying drawings and embodiments.

[0055] like Figure 1 As shown, first-principles calculations determined that W-based carbides in cermet materials exhibit better overall performance than Fe-based or Cr-based carbides, with higher hardness and modulus, but slightly lower toughness. Considering the requirements for hardness and wear resistance, W3Co3C was selected as the endogenous carbide, and Co as the metallic binder phase. Mo can increase the wettability between ceramic particles and the metallic phase, while Ta and Nb have a grain-refining effect. Calculations showed that the (Ti,W,Mo,Nb,Ta)(C,N) ceramic particles have a hardness >30 GPa, and the hardness of the friction oxides Ti, Co, and Ta oxides are all above 5 GPa. Therefore, the cermet composition (Ti,W,Mo,Nb,Ta)(C,N) was selected.

[0056] Obtain binary and ternary thermodynamic databases, with elements representing those in the target cermet, establish a thermodynamic model, and calculate the Gibbs free energy of common phases in the system. Integrate and expand the calculation results to establish a phase diagram thermodynamic database for the cermet system. Based on the thermodynamic database, perform phase diagram calculations for the cermet system to obtain the total atomic content of C and N and the sintering temperature range, such as... Figure 2 As shown.

[0057] Based on the above calculation results, a metal-ceramic material was prepared. The total mass of the metal-ceramic material was 1 kg, including: 900 g of high-entropy ceramic powder and 100 g of Co powder. The high-entropy ceramic had a composition of (Ti,W,Mo,Nb,Ta)(C,N), with each element by mass percentage as follows: Ti: 12%, W: 12%, Mo: 12%, Nb: 12%, Ta: 12%, with the total atomic percentage of metal elements being 50%; C: 25%, N: 15%, with the total atomic percentage of C and N being 40%.

[0058] The preparation process is as follows: Weigh 900 g of (Ti,W,Mo,Nb,Ta)(C,N) powder and 100 g of Co powder.

[0059] (Ti,W,Mo,Nb,Ta)(C,N) powder, 100 g of Co powder, and an additional 20 g of paraffin wax were placed in a ball mill jar. 500 ml of anhydrous ethanol was added, along with 5 kg of cemented carbide grinding balls, and the mixture was ball-milled for dispersion. The ball mill speed was 150 r / min, and the milling time was 6 h. The ball-milled powder was dried and sieved sequentially through 40-mesh and 60-mesh sieves to obtain uniformly sized cermet powder. The cermet powder was pressed using a press to obtain several powder block products. The cermet powder blocks were placed in a vacuum sintering furnace for sintering. After evacuating the furnace, Ar was introduced at a pressure of 0.5 kPa, and the temperature was rapidly raised to 500℃ and held for 0.5 h for dewaxing. After dewaxing, the furnace temperature was raised from 500℃ to 1450℃ and held for 30 min. Finally, the temperature was cooled for 0.5 h, and the sintered cermet samples were removed from the furnace.

[0060] The cermet material prepared in this embodiment has a hardness of 1750-1850 HV30 at room temperature and a fracture toughness of 9-10 MPa∙m. 1 / 2 In wear tests of Al2O3 ceramic balls under a 5 N load, the wear rate at room temperature was 2.8 × 10⁻⁶. -7 ±0.5 mm 3 / (N∙m), the wear rate at 600℃ is 2.6×10 -5 ±0.7 mm 3 / (N∙m). The statistical comparison of the results of Example 1 and Comparative Example 1 is shown in Table 1.

[0061] Figure 3 The image shows the microstructure of the high-entropy cermet material in this embodiment. As can be seen from the image, the particle size of the high-entropy ceramic is 0.5-10 μm, and the particle size of the metal binder phase Co is 0.5-30 μm. In addition to the high-entropy ceramic (Ti,W,Mo,Nb,Ta)(C,N) particles and the metal binder phase Co, white compounds are also present. Figure 4 The EDS results confirmed that the compound was MoWCoC.

[0062] Figure 5 The results of calculation and testing of hardness, elastic modulus, bulk modulus / shear modulus, and Cauchy pressure of ceramic particles, binder phase, endogenous carbides, and friction products in metal-ceramic composite materials in Example 1 and Comparative Example 1 are presented. Figure 6 This is a SEM image of the friction surface of the high-entropy cermet material at 600℃ in this embodiment. The main wear mechanism at 600℃ is abrasive wear. The results show that the hardness of the cermet material prepared in Example 1 is 1750-1850 HV30, and the fracture toughness is 9-10 MPa∙m. 1 / 2 It is superior to the hardness and fracture toughness of the cermet material in Comparative Example 1 (1400-1500 HV30, fracture toughness 8-9 MPa∙m). 1 / 2 The improved performance of the metal-ceramic materials prepared in the examples is mainly due to two factors: firstly, the excellent properties of the (Ti,W,Mo,Nb,Ta)(C,N) high-entropy ceramics themselves; secondly, the performance can be attributed to the MoWCoC compound, which acts as an endogenous reinforcement, bearing the load during material loading and improving the mechanical properties of the material. The different hardness and heat resistance of the materials in the examples and the comparative examples resulted in significant differences in their wear resistance. The metal-ceramic material prepared in the examples had a room temperature wear rate of 2.8 × 10⁻⁷ ± 0.5 mm. 3 / (N∙m), the wear rate at 600℃ is 2.6×10⁻⁵±0.7 mm. 3 / (N∙m), the wear rate is increased by more than 50% compared to the comparative material. The improved wear resistance of the example is due to the excellent properties of the (Ti,W,Mo,Nb,Ta)(C,N) high-entropy ceramic and the endogenous reinforcement MoWCoC compound.

[0063] Comparative Example 1 A cermet material, with a total mass of 1 kg. The ceramic powder consists of 900 g of Ti(C,N) powder, and the metal powder consists of 100 g of Co powder. 20 g of paraffin wax is used as the powder binder.

[0064] Except for the different material ratios, 500 ml of anhydrous ethanol was added as a dispersant, and the preparation method was the same as in Example 1.

[0065] The Ti(C,N) cermet material prepared in this comparative example has a hardness of 1400-1500 HV30 at room temperature and a fracture toughness of 8-9 MPa∙m. 1 / 2 Wear tests on Al2O3 ceramic balls under a 5 N load showed a wear rate of 1.8 × 10⁻⁶ ± 0.5 mm at room temperature. 3 / (N∙m), the wear rate at 600℃ is 5.9×10⁻⁵±0.9 mm. 3 / (N∙m).

[0066] from Figure 7 It can be seen that a large area of ​​material detachment occurred on the friction surface of the comparative Ti(C,N) cermet material at 600℃, while the friction grooves basically disappeared. This indicates that the material underwent thermal softening during the friction process at 600℃, resulting in large-area deformation and detachment. The main wear mechanism was delamination wear. Table 1. Hardness, fracture toughness, and wear rate at room temperature and 600°C for the examples and comparative examples. The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A design method for endogenous carbide-reinforced metal-ceramic materials, characterized in that, Includes the following steps: (1) Predict the mechanical properties of ceramic phase, endogenous carbides, and tribological oxides in cermet materials using first-principles calculations; (2) Based on mechanical properties, screening criteria were set to screen out ceramic phases, endogenous carbides, and tribooxides to obtain the target metal ceramic system and determine the types of constituent elements; (3) Combine phase diagram calculations to determine the composition range of different phases in the target metal-ceramic system and the sintering window of the metal-ceramic material; (4) Based on the types of constituent elements determined in step (2) and the composition range and sintering window determined in step (3), metal ceramic materials and their preparation methods are designed.

2. The metal-ceramic material design method according to claim 1, characterized in that, In step (1), the mechanical properties predicted by the first-principles calculation method include: obtaining the phase cell parameters of ceramic phase, endogenous carbide and tribooxide in the cermet material, calculating the intrinsic elastic constant matrix, and obtaining the bulk modulus, shear modulus and hardness.

3. The metal-ceramic material design method according to claim 2, characterized in that, In step (2), the screening criteria are set to screen out ceramic phase, endogenous carbide, and friction oxide, including: calculating the ratio of bulk modulus to shear modulus and Cauchy pressure based on bulk modulus, shear modulus, and hardness, and setting screening criteria to screen out ceramic phase, endogenous carbide, and friction oxide. The screening criteria for both the ceramic phase and the friction oxide prioritized hardness; specifically, the screening criterion for the ceramic phase was a hardness greater than 30 GPa, and the screening criterion for the friction oxide was a hardness greater than 5 GPa. The screening criteria for endogenous carbides are a volume modulus to shear modulus ratio greater than 1.5 or a Cauchy pressure greater than 0.

4. A metal-ceramic material, characterized in that, The material is obtained using the design method described in any one of claims 1-3, based on the total mass of the cermet material, comprising 70-90 wt% high-entropy ceramic particles and the balance being a metallic binder phase; The high-entropy ceramic particles are carbides or carbonitrides formed by any five or six elements selected from Ti, Nb, W, Mo, Ta, V, Zr, and Hf, including at least one of Mo and W; the particle size of the high-entropy ceramic particles is 0.5-10 μm. The metal binder phase includes at least one of Co and Ni; the particle size of the metal binder phase is 0.5-30 μm.

5. The metal-ceramic material according to claim 4, characterized in that, The high-entropy ceramic particles contain ≥95% single-phase high-entropy ceramic and <5% other ceramic. Mo or W has an atomic ratio ≥10% in high-entropy ceramic particles.

6. The metal-ceramic material according to claim 4, characterized in that, The aforementioned metal-ceramic material has a hardness ≥1500 HV30 and a fracture toughness ≥9 MPa∙m at room temperature. 1 / 2 Abrasive wear rate at room temperature ≤7×10 -7 mm 3 / (N∙m), abrasive wear rate at 600℃ ≤1×10 -4 mm 3 (N∙m).

7. A method for preparing a metal-ceramic material according to any one of claims 4-6, characterized in that, The high-entropy ceramic particles and the metal binder phase are uniformly mixed using a wet ball milling method, and then the metal-ceramic material is prepared by rapid negative pressure sintering. The specific steps include: (1) Based on the total weight, weigh the high-entropy ceramic particle raw material, metal powder raw material and forming agent to obtain the precursor powder, disperse it in the solvent and ball mill it evenly; (2) After the precursor powder is dried and sieved, it is pressed into shape and then sintered under a negative pressure in an inert atmosphere to obtain a metal ceramic material.

8. The preparation method according to claim 7, characterized in that, In step (1), the mass ratio of grinding balls to precursor powder is 3-10:1, the ball milling speed is 50-300 r / min, and the ball milling time is 4-12 h.

9. The preparation method according to claim 7, characterized in that, The rapid negative pressure sintering described in step (2) includes: placing the pressed precursor powder into a sintering furnace, heating it to a first temperature and holding it at that temperature to remove wax; after removing wax, heating it to a second temperature and holding it at that temperature for sintering; after sintering, introducing an inert atmosphere to cool it to a third temperature; and then using a water cooling system to obtain a metal ceramic material.

10. The preparation method according to claim 9, characterized in that, The total sintering time in the sintering furnace is ≤4.5 h; The first temperature is 500℃, the corresponding holding time is 30 min, and the heating time is ≤2.5 h; The second temperature is 1400℃-1500℃, and the corresponding holding time is ≤2 h; where the time above 1200℃ is ≤2 h.

11. The third temperature is 1000℃, and the cooling time is ≤1 h; The sintering process is vacuum negative pressure sintering, during which the furnace pressure is 0.5-20 kPa and after dewaxing, the furnace pressure is 2-20 kPa.

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