Wear-resistant, corrosion-resistant and high-temperature-resistant metal ceramic composite material for laser cladding and preparation method thereof

Abstract

The invention is applicable to the technical field of preparation of metal ceramic composite materials, and provides a wear-resistant, corrosion-resistant and high-temperature-resistant metal ceramic composite material for laser cladding and a preparation method of the metal ceramic composite material for laser cladding. The composite material comprises the following components in percentage by weight: 3%-6% of an intermetallic compound, 35%-42% of a ceramic reinforced phase, 8%-16% of nitride, 6%-12% of oxide, 6%-10% of an additive, 1%-2% of graphene and 0.6%-1.2% of nano hafnium carbide Performance breakthrough is achieved through multi-dimensional collaborative design, specifically, high-hardness carbide and nitride provide abrasion resistance, and oxide and intermetallic compounds enhance oxidation resistance / corrosion resistance; the boron nitride-silicon nitride particle size gradient constructs a low-friction and strong-heat-dissipation interface network, optimizes the microstructure, and adapts to high-temperature and high-speed working conditions; strong coupling of graphene and a metal matrix is achieved through nano regulation and control of the C-O-M bonding layer, the interface strength is improved, and finally dynamic balance of hardness, toughness, abrasion resistance, oxidation resistance, corrosion resistance and thermal shock resistance is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation of cermet composites, and particularly relates to a wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding and a preparation method thereof. Background Art

[0002] As a class of advanced materials composed of ceramic phases and metal phases, cermet composites exhibit significant advantages in enhancing material hardness, wear resistance, etc.; however, the existing technical solutions still face the following limitations: 1. Defects of single strengthening phases: Although traditional carbides or nitrides can enhance hardness, their thermal shock resistance and corrosion resistance are insufficient; although oxide or intermetallic compound coatings can resist oxidation, their bonding strength with the substrate is weak and they are prone to peeling, which limits the long-term reliability of the materials. 2. Interface bonding problems: The difference in thermal expansion coefficients between ceramic particles and the metal matrix leads to concentrated interfacial residual stresses, triggering crack propagation; traditional interface modification methods, such as electroless plating or surface coating, are difficult to achieve atomic-level bonding, with poor interface stability and unable to effectively transfer loads. 3. Insufficient microstructure regulation: Particle agglomeration and uneven size distribution result in large fluctuations in performance, making it difficult to achieve multi-scale synergistic strengthening; at the same time, the lack of gradient design for lubricating and wear-resistant phases makes it difficult to balance tribological properties and thermal stability, limiting the application potential of the materials under extreme working conditions. Summary of the Invention

[0003] The present invention provides a wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding and a preparation method thereof, aiming to solve the problems that although the existing cermet composites can improve hardness and wear resistance, there are limitations such as single strengthening phases leading to weak thermal shock resistance, corrosion resistance, easy peeling of oxide coatings, poor interface bonding, insufficient stability, and uneven microstructure regulation, lack of lubrication, and lack of gradient design for wear-resistant phases, which limit their application under extreme working conditions.

[0004] The present invention is realized as follows. A wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding includes, by mass percentage: A metal matrix, 45%-55%, using any one of nickel-based alloys or cobalt-based alloys, which includes, by atomic percentage: 18%-22% chromium, 4%-7% silicon, 2%-4% molybdenum and 3%-6% boron; Intermetallic compounds: 3%-6%, a mixture composed of 1%-3% nickel-aluminum intermetallic compounds and 2%-3% nickel-titanium intermetallic compounds; Ceramic reinforcing phases, 35%-42%, including: Carbides: 12%-18%, a mixture composed of 5%-10% tungsten carbide, 3%-8% titanium carbide and 2%-5% tantalum carbide; Nitride: 8% - 16%, a mixture composed of 5% - 10% silicon nitride and 3% - 8% boron nitride; Oxide: 6% - 12%, a mixture composed of 3% - 7% aluminum oxide and 3% - 5% zirconium oxide; Additive, 6% - 10%, including: 6% - 9% rare earth oxide, a mixture composed of 2% - 4% yttrium oxide, 2% - 3% lanthanum oxide and 1% - 2% cerium oxide; 1% - 2% graphene; 0.6% - 1.2% hafnium carbide nanoparticles. Preferably, the total atomic percentage of chromium, silicon and boron is 20% - 38%, and the atomic ratio of chromium to boron ≥ 5:1.

[0005] Preferably, the ratio of the total mass of carbide to the total mass of nitride and oxide is (3 - 5):(7 - 10).

[0006] Preferably, hafnium carbide nanoparticles are dispersed in the ceramic phase gaps in a granular form, with a particle size ≤ 50 nm and a filling rate ≥ 90%.

[0007] Preferably, graphene is dispersed in the metal matrix in a lamellar structure, with a sheet diameter of 1 - 10 μm and the number of layers ≤ 5.

[0008] Preferably, the hexagonal crystal form of boron nitride accounts for ≥ 95%, and the particle size ratio of silicon nitride to boron nitride is 1:0.5 - 1:2.

[0009] Preferably, a C - O - M bonding layer is formed at the interface between graphene and the metal matrix, and the thickness of the bonding layer is 0.5 - 1.5 nm.

[0010] The present invention also provides a preparation method of a wear - resistant, corrosion - resistant and high - temperature - resistant metal - ceramic composite material for laser cladding, including the following steps: Step 1: Pretreatment of the metal matrix 1. Alloy selection: Select a nickel - based alloy or a cobalt - based alloy according to 45% - 55% by mass percentage; 2. Atomic regulation: Precisely add 18% - 22% chromium, 4% - 7% silicon, 2% - 4% molybdenum and 3% - 6% boron to ensure that the chromium / boron atomic ratio ≥ 5:1, forming an antioxidant, anti - thermal - corrosion and high - toughness matrix; Step 2: Preparation of intermetallic compounds and ceramic reinforcing phases 1. Intermetallic compounds: Mix 1% - 3% nickel - aluminum intermetallic compounds and 2% - 3% nickel - titanium intermetallic compounds to enhance high - temperature strength and oxidation resistance; 2. Ceramic reinforcing phases: ①. Carbide: 5% - 10% tungsten carbide, 3% - 8% titanium carbide, 2% - 5% tantalum carbide, providing high hardness; ②. Nitrides: 5%-10% silicon nitride, 3%-8% boron nitride, showing high-temperature stability and self-lubricity; ③. Oxides: 3%-7% aluminum oxide, 3%-5% zirconium oxide, enhancing oxidation resistance and thermal shock resistance; 3. Ratio optimization: Controlling carbide:nitride + oxide = 3-5:7-10 to achieve a dynamic balance between hardness and toughness; Step 3: Additive design and interface regulation ①. Rare earth oxides: Adding 2%-4% yttrium oxide, 2%-3% lanthanum oxide, 1%-2% cerium oxide to refine grains and improve strength and toughness; ②. Graphene: Dispersed in the metal matrix with a sheet diameter of 1-10 μm and a structure of ≤5 layers to form a C-O-M bonding layer, enhancing thermal conductivity and thermal shock resistance; ③. Nanocrystalline hafnium carbide: Particle size ≤50 nm, filling rate ≥90%, improving wear resistance and thermal shock resistance; ④. Boron nitride / silicon nitride: The proportion of hexagonal crystal form ≥95%, particle size ratio 1:0.5-1:2, constructing a low-friction and high-wear-resistant interface network; Step 4: Composite material forming and performance optimization 1. Laser cladding: Mix the pretreated metal matrix with reinforcing phases and additives, and form a uniform composite layer through the laser cladding process; 2. Microstructure regulation: Utilize the interface pinning effect of nanocrystalline hafnium carbide, the two-dimensional reinforcement mechanism of graphene, and the particle size gradient design of boron nitride / silicon nitride to achieve the synergistic improvement of the strength, toughness, wear resistance, and thermal stability of the material; 3. Performance verification: Through experimental tests, ensure that the material has long-term stability under extreme working conditions such as high temperature, high speed, and strong corrosion.

[0011] Compared with the prior art, the embodiments of the present application mainly have the following beneficial effects: First: The present invention realizes the dynamic balance of hardness, toughness, wear resistance, oxidation resistance, corrosion resistance, and thermal shock resistance; its high-hardness carbides and hard nitrides provide excellent wear resistance, while oxides and intermetallic compounds enhance oxidation and corrosion resistance; at the same time, the addition of nanocrystalline hafnium carbide and graphene further improves the thermal shock resistance and toughness of the material, making it perform excellently under complex working conditions such as high temperature, wear, and corrosion, and significantly extending the service life.

[0012] Second: The microstructure of the composite material of the present invention has been finely optimized, realizing the synergistic effect of each component, the high-density filling and uniform dispersion of hafnium carbide nanoparticles, and the two-dimensional nano-reinforcement mechanism of graphene, significantly improving the mechanical properties and thermal stability of the material. In addition, the particle size gradient design of boron nitride and silicon nitride constructs a multi-functional interface network with low friction, high wear resistance, and strong heat dissipation, further optimizing the microstructure of the material and enabling it to operate stably for a long time under high-temperature and high-speed conditions.

[0013] Third: Through the nano-regulation of the C-O-M bonding layer, the present invention realizes a strong coupling effect between graphene and the metal matrix, significantly improving the interfacial bonding strength. This interfacial strengthening mechanism not only enhances the strength and toughness of the material but also alleviates the difference in thermal expansion coefficient through the gradient chemical composition, inhibiting interfacial debonding during the thermal cycle, thereby greatly improving the thermal fatigue resistance of the material. Brief Description of the Drawings

[0014] Figure 1 is a schematic diagram of the preparation of the cermet composite material of the present invention; Detailed Description of the Embodiments

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the description of this application in the specification are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above description of the drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of this application or the above drawings are used to distinguish different objects and are not used to describe a specific order.

[0016] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0017] The embodiment of the present invention provides a wear-resistant, corrosion-resistant, and high-temperature-resistant cermet composite material for laser cladding, as Figure 1 shown, including by mass percentage: A metal matrix, 45%-55%, using any one of nickel-based alloys or cobalt-based alloys, which includes by atomic percentage: 18%-22% chromium, 4%-7% silicon, 2%-4% molybdenum, and 3%-6% boron; Intermetallic compound: 3% - 6%, a mixture composed of 1% - 3% nickel aluminide and 2% - 3% nickel titanide; Ceramic reinforcing phase, 35% - 42%, including: Carbide: 12% - 18%, a mixture composed of 5% - 10% tungsten carbide, 3% - 8% titanium carbide and 2% - 5% tantalum carbide; Nitride: 8% - 16%, a mixture composed of 5% - 10% silicon nitride and 3% - 8% boron nitride; Oxide: 6% - 12%, a mixture composed of 3% - 7% alumina and 3% - 5% zirconia; Additive, 6% - 10%, including: 6% - 9% rare earth oxide, a mixture composed of 2% - 4% yttrium oxide, 2% - 3% lanthanum oxide and 1% - 2% cerium oxide; 1% - 2% graphene; 0.6% - 1.2% hafnium carbide nanometer.

[0018] It should be noted that although the existing cermet composites can improve hardness and wear resistance, there are limitations such as single strengthening phase resulting in weak thermal shock resistance, corrosion resistance, easy spalling of oxide coatings, poor interface bonding, insufficient stability, uneven regulation of microstructure, lack of lubrication, and lack of wear-resistant phase gradient design, which limit the application in extreme working conditions. This solution realizes the dynamic balance of hardness, toughness, wear resistance, oxidation resistance, corrosion resistance and thermal shock resistance; its high-hardness carbides and hard nitrides provide excellent wear resistance, and oxides and intermetallic compounds enhance antioxidant and corrosion resistance; further improve the thermal shock resistance and toughness of the material, and significantly enhance the mechanical properties and thermal stability; in addition, the particle size gradient design of boron nitride and silicon nitride constructs a multifunctional interface network with low friction, high wear resistance and strong heat dissipation, optimizes the microstructure, and enables it to operate stably for a long time under high-temperature and high-speed working conditions; at the same time, through the nano-regulation of the C - O - M bonding layer, the strong coupling effect between graphene and the metal matrix is realized, significantly improving the interface bonding strength, alleviating the difference in thermal expansion coefficient, inhibiting interface debonding during the thermal cycle, and greatly improving the thermal fatigue resistance of the material.

[0019] Specifically, in this embodiment, the composite material uses 45% - 55% nickel-based alloy or cobalt-based alloy as the metal matrix by precisely controlling the atomic percentage, adding 18% - 22% chromium to form a dense chromium oxide film to improve antioxidant and corrosion resistance; 4% - 7% silicon forms a stable silicate protective film at high temperature to enhance the thermal corrosion resistance; 2% - 4% molybdenum improves wear resistance and thermal fatigue resistance, and at the same time improves high-temperature strength and toughness; 3% - 6% boron reduces the melting point, optimizes the wettability and spreading property of laser cladding, and improves hardness and wear resistance; The 3%-6% intermetallic compounds serve as a bridge between the metal matrix and the ceramic reinforcement phase. Among them, 1%-3% nickel aluminide compounds form a dense alumina film to prevent oxidation; 2%-3% nickel titanium compounds improve the high-temperature strength and creep resistance, and enhance the oxidation resistance. The 35%-42% ceramic reinforcement phase significantly improves the material properties through high hardness, high wear resistance, and high thermal stability; carbides provide extremely high hardness and wear resistance; nitrides exhibit excellent high-temperature stability and oxidation resistance; oxides enhance the oxidation resistance and thermal shock resistance. Additives further optimize the material properties; 6%-9% rare earth oxides form a dense oxide film, refine the grains, and improve the strength and toughness; 1%-2% graphene enhances the thermal conductivity and thermal shock resistance, and improves the toughness and crack resistance; 0.6%-1.2% hafnium carbide nanoparticles improve the wear resistance, thermal shock resistance, oxidation resistance, and corrosion resistance.

[0020] In a further preferred embodiment of the present invention, as Figure 1 shown, the total atomic percentage of chromium, silicon, and boron is 20%-38%, and the atomic ratio of chromium to boron ≥ 5:1.

[0021] In this embodiment, the total atomic percentage of chromium, silicon, and boron is strictly controlled within the range of 20%-38%, and it is ensured that the atomic ratio of chromium to boron ≥ 5:1. This ratio not only ensures the dominant role of chromium in oxidation resistance but also avoids the increase in brittleness caused by excessive boron, achieving a dynamic balance between rigidity and toughness.

[0022] In a further preferred embodiment of the present invention, as Figure 1 shown, the ratio of the total mass of carbides to the total mass of nitrides and oxides is (3-5):(7-10).

[0023] In this embodiment, the ratio of the total mass of carbides to the total mass of nitrides and oxides is strictly controlled within the range of (3-5):(7-10); a high ratio of nitrides / oxides can form a continuous and stable nitride / oxide coating, effectively hindering crack propagation and enhancing the oxidation / corrosion resistance; while an appropriate amount of carbides as the strengthening phase enhances the material hardness and wear resistance through dispersion; this ratio, through the synergistic effect of the toughness of the nitride / oxide matrix and the hard carbide phase, not only avoids the brittle risk caused by excessive single carbides but also prevents the strength decline caused by excessive nitrides / oxides, ultimately achieving a dynamic balance among hardness, toughness, and corrosion resistance.

[0024] In a further preferred embodiment of the present invention, as Figure 1 shown, hafnium carbide nanoparticles are dispersed in the gaps between ceramic phases in a particulate form, with a particle size ≤ 50 nm and a filling rate ≥ 90%.

[0025] In this embodiment, hafnium carbide nanoparticles are uniformly dispersed in the interstices of the ceramic matrix phase at a scale with a particle size ≤ 50 nm, and high-density filling with a filling rate ≥ 90% is achieved through process optimization; the high-filling-rate nano-HfC particles serve as the second-phase strengthener. On the one hand, they significantly hinder the dislocation movement and crack propagation in the ceramic matrix through the interface pinning effect, improving the flexural strength and fracture toughness of the material; on the other hand, the HfC particles with nano-scale particle size form a thermal expansion coefficient gradient transition layer with the ceramic matrix, effectively alleviating the concentration of thermal stress and enhancing the thermal shock resistance of the material; in addition, the high hardness property of the HfC particles further improves the wear resistance and erosion resistance of the composite material; through the multi-scale strengthening mechanism at the nano-scale, this design realizes the transformation of the brittleness of the ceramic material to toughness at the micro level, while retaining the inherent high-temperature stability and chemical inertness of the ceramic matrix, and finally constructs a multi-functional composite ceramic system with high hardness, high toughness, and excellent thermal / chemical stability.

[0026] In a further preferred embodiment of the present invention, as Figure 1 shown, graphene is dispersed in the metal matrix in a sheet structure with a sheet diameter of 1 - 10 μm and the number of layers ≤ 5 layers.

[0027] In this embodiment, few-layer graphene is uniformly dispersed in the metal matrix in a two-dimensional sheet structure with a sheet diameter of 1 - 10 μm to form a nano-scale interface strengthening network; the high specific surface area of graphene forms a strong interface bond with the metal matrix, significantly improving the yield strength and tensile strength of the material through the load transfer effect; the sheet slip blocking effect of graphene can effectively disperse the stress at the crack tip, inducing crack deflection and bridging, greatly enhancing the fracture toughness of the material; at the same time, the high thermal conductivity of few-layer graphene and the metal matrix act synergistically to construct a three-dimensional heat conduction channel, significantly improving the heat dissipation efficiency of the material; in addition, the chemically inert layered structure of graphene can hinder the penetration of corrosive media, enhancing the corrosion resistance of the material; through the two-dimensional nano-reinforcement mechanism of graphene, this design realizes the synergistic improvement of the strength, toughness, and thermal / chemical stability of the metal material at the micro scale, and finally constructs an advanced metal matrix composite material system with super mechanical properties and multi-functionality.

[0028] In a further preferred embodiment of the present invention, as Figure 1 shown, the proportion of the hexagonal crystal form of boron nitride is ≥ 95%, and the particle size ratio of silicon nitride to boron nitride is 1:0.5 - 1:2.

[0029] In this embodiment, the hexagonal crystal form content of boron nitride is strictly controlled to be ≥95% to ensure the integrity of its layered structure, thereby endowing the material with excellent self-lubricity and thermal conductivity. At the same time, the particle size ratio of silicon nitride to boron nitride is designed to be 1:0.5 - 1:2, and the microstructure is optimized through particle size gradient regulation. Its core working principle is as follows: High-purity hexagonal boron nitride serves as the solid lubricating phase, and the weak van der Waals force between its layers can significantly reduce the friction coefficient of the material. Silicon nitride serves as the hard reinforcing phase, which can improve the density and wear resistance through fine particle size, or form a crack deflection path through coarse particle size to enhance the fracture toughness. Through the lubrication - heat dissipation synergistic effect of boron nitride and the strength - toughness complementary mechanism of silicon nitride, a multifunctional interface network with low friction, high wear resistance, and strong heat dissipation is constructed at the micro level, ultimately achieving the long-term stable operation of the material under high-temperature and high-speed working conditions.

[0030] In a further preferred embodiment of the present invention, as Figure 1 shown, a C - O - M bonding layer is formed at the interface between graphene and the metal matrix, and the thickness of the bonding layer is 0.5 - 1.5 nm.

[0031] In this embodiment, the oxygen atoms in the C - O - M bonding layer act as active media. Through chemical adsorption and diffusion reactions, strong covalent / ionic hybrid bonds are formed between graphene and the metal matrix, effectively eliminating interface voids and significantly enhancing the interface bonding strength. Through the interface stress transfer effect, the high modulus characteristics of graphene and the ductility of the metal matrix are synergistically coupled to achieve efficient load distribution in the composite material, thereby enhancing the strength and toughness of the material simultaneously. In addition, the gradient chemical composition of the bonding layer can alleviate the difference in thermal expansion coefficients between graphene and the metal matrix, inhibit interface debonding during the thermal cycle, and improve the thermal fatigue resistance of the material. Through the nano-regulation of interface chemical bonding, a strong coupling effect between graphene and the metal matrix is achieved at the atomic scale, ultimately constructing an advanced composite material system with both excellent mechanical properties and thermal stability.

[0032] Working principle: This composite material uses a nickel-based alloy or cobalt-based alloy with a mass percentage of 45% - 55% as the metal matrix. By precisely regulating the atomic percentage and adding 18% - 22% of chromium, a dense chromium oxide film can be formed, thereby improving the oxidation resistance and corrosion resistance of the material. At the same time, adding 4% - 7% of silicon enables it to form a stable silicate protective film at high temperatures, further enhancing the hot corrosion resistance of the material. In addition, adding 2% - 4% of molybdenum can improve the wear resistance and thermal fatigue resistance of the material, while improving its high-temperature strength and toughness. The addition of 3% - 6% of boron can reduce the melting point of the material, optimize the wettability and spreadability of laser cladding, and improve the hardness and wear resistance of the material. Intermetallic compounds account for 3% - 6%. As a bridge between the metal matrix and the ceramic reinforcement phase, 1% - 3% of nickel-aluminum intermetallic compounds can form a dense alumina film to effectively prevent oxidation; 2% - 3% of nickel-titanium intermetallic compounds can improve the high-temperature strength and creep resistance of the material, while enhancing its oxidation resistance; The ceramic reinforcement phase accounts for 35% - 42%. It significantly improves the material properties through its high hardness, high wear resistance, and high thermal stability. Among them, carbides provide extremely high hardness and wear resistance; nitrides exhibit excellent high-temperature stability and oxidation resistance; oxides enhance oxidation resistance and thermal shock resistance; Additives further optimize the material properties. 6% - 9% of rare earth oxides can form a dense oxide film, refine the grains, and thus improve the strength and toughness of the material; 1% - 2% of graphene can enhance the thermal conductivity and thermal shock resistance of the material, and improve its toughness and crack resistance; 0.6% - 1.2% of nano hafnium carbide can improve the wear resistance, thermal shock resistance, oxidation resistance, and corrosion resistance of the material; In terms of the ratio, the total atomic percentage of chromium, silicon, and boron is strictly controlled within the range of 20% - 38%, and it is ensured that the atomic ratio of chromium to boron ≥ 5:1. This ratio not only ensures the dominant role of chromium in oxidation resistance but also avoids the increase in brittleness caused by excessive boron, thus achieving a dynamic balance between rigidity and toughness; The ratio of the total mass of carbides to the total mass of nitrides and oxides is strictly controlled within the range of (3 - 5):(7 - 10). A high nitride / oxide ratio can form a continuous and stable nitride / oxide coating, effectively hindering crack propagation and enhancing oxidation / corrosion resistance; while an appropriate amount of carbides, as a strengthening phase, enhances the hardness and wear resistance of the material through dispersion distribution. This ratio, through the synergistic effect of the toughness of the nitride / oxide matrix and the hard carbide phase, not only avoids the brittle risk caused by excessive single carbides but also prevents the strength decline caused by excessive nitrides / oxides, ultimately achieving a dynamic balance among hardness, toughness, and corrosion resistance; Nano hafnium carbide particles are uniformly dispersed in the interstices of the ceramic matrix phase at a scale with a particle size ≤ 50 nm, and through process optimization, a high-density filling with a filling rate ≥ 90% is achieved. The high-filling-rate nano HfC particles, as the second-phase strengthening body, on the one hand, significantly hinder the dislocation movement and crack propagation in the ceramic matrix through the interface pinning effect, improving the flexural strength and fracture toughness of the material; on the other hand, the nano-sized HfC particles and the ceramic matrix form a thermal expansion coefficient gradient transition layer, effectively alleviating the thermal stress concentration and enhancing the thermal shock resistance of the material. In addition, the high hardness characteristics of HfC particles further improve the wear resistance and erosion resistance of the composite material. This design realizes the transformation of the brittleness of ceramic materials to toughness at the micro level through a multi-scale strengthening mechanism at the nano scale, while retaining the inherent high-temperature stability and chemical inertness of the ceramic matrix, and finally constructs a multifunctional composite ceramic system with high hardness, high toughness, and excellent thermal / chemical stability; Few-layer graphene is uniformly dispersed in the metal matrix in the form of two-dimensional sheet structures with a sheet diameter of 1-10 μm, forming a nano-scale interface strengthening network; the high specific surface area of graphene forms a strong interface bond with the metal matrix, and significantly improves the yield strength and tensile strength of the material through the load transfer effect; the sheet slip barrier effect of graphene can effectively disperse the stress at the crack tip, induce crack deflection and bridging, and greatly enhance the fracture toughness of the material; at the same time, the high thermal conductivity of few-layer graphene and the metal matrix act synergistically to construct a three-dimensional heat conduction channel, significantly improving the heat dissipation efficiency of the material; in addition, the chemically inert layered structure of graphene can hinder the penetration of corrosive media and enhance the corrosion resistance of the material; this design realizes the synergistic improvement of the strength, toughness and thermal / chemical stability of metal materials at the microscale through the two-dimensional nano-reinforcement mechanism of graphene, and finally constructs an advanced metal matrix composite material system with both super mechanical properties and multifunctionality; The hexagonal crystal form content of boron nitride is strictly controlled at ≥95% to ensure the integrity of its layered structure, thereby endowing the material with excellent self-lubricity and thermal conductivity; at the same time, the particle size ratio of silicon nitride to boron nitride is designed to be 1:0.5-1:2, and the microstructure is optimized through particle size gradient regulation; its core working principle is: high-purity hexagonal boron nitride as a solid lubricating phase, the weak van der Waals force between its layers can significantly reduce the friction coefficient of the material, while silicon nitride as a hard reinforcing phase can improve the density and wear resistance through fine particle size, or form a crack deflection path through coarse particle size to enhance the fracture toughness; this ratio constructs a multifunctional interface network with low friction, high wear resistance and strong heat dissipation at the micro level through the lubrication-heat dissipation synergistic effect of boron nitride and the strength-toughness complementary mechanism of silicon nitride, and finally realizes the long-term stable operation of the material under high-temperature and high-speed working conditions; The oxygen atoms in the C-O-M bonding layer act as active media, and form strong covalent / ionic hybrid bonds between graphene and the metal matrix through chemical adsorption and diffusion reactions, effectively eliminating interface voids and significantly improving the interface bonding strength; this bonding layer synergistically couples the high modulus characteristics of graphene and the ductility of the metal matrix through the interface stress transfer effect, realizing the efficient distribution of load in the composite material, thereby enhancing the strength and toughness of the material at the same time; in addition, the gradient chemical composition of the bonding layer can alleviate the difference in thermal expansion coefficient between graphene and the metal matrix, inhibit interface debonding during the thermal cycle, and improve the thermal fatigue resistance of the material; this design realizes the strong coupling effect between graphene and the metal matrix at the atomic scale through the nano-regulation of interface chemical bonding, and finally constructs an advanced composite material system with both super mechanical properties and excellent thermal stability.

[0033] It should be noted that for the foregoing embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the present invention is not limited by the described action sequence, because according to the present invention, certain steps may be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0034] In several embodiments provided by the present application, it should be understood that the disclosed device can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the above-mentioned unit division may have other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or communication connection between each other can be through some interfaces. The indirect coupling or communication connection between devices or units can be in the form of telecommunications or other forms.

[0035] The units described as separate components above may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0036] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting the protection scope of the invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on these embodiments, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art can still, without conflict and without creative efforts, combine, add, delete or make other adjustments to the features in the embodiments of the present invention according to the circumstances, so as to obtain different technical solutions that essentially do not deviate from the concept of the present invention. These technical solutions also belong to the scope of protection of the present invention.

Claims

1. A wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding, characterized in that, Comprising by mass percentage: A metal matrix, 45% - 55%, any one of nickel-based alloys or cobalt-based alloys, which by atomic percentage comprises: 18% - 22% chromium, 4% - 7% silicon, 2% - 4% molybdenum and 3% - 6% boron; Intermetallic compound: 3% - 6%, a mixture composed of 1% - 3% nickel-aluminum intermetallic compound and 2% - 3% nickel-titanium intermetallic compound; Ceramic reinforcement phase, 35% - 42%, including: Carbide: 12% - 18%, a mixture composed of 5% - 10% tungsten carbide, 3% - 8% titanium carbide and 2% - 5% tantalum carbide; Nitride: 8% - 16%, a mixture composed of 5% - 10% silicon nitride and 3% - 8% boron nitride; Oxide: 6% - 12%, a mixture composed of 3% - 7% alumina and 3% - 5% zirconia; Additives, 6% - 10%, including: 6% - 9% rare earth oxides, a mixture composed of 2% - 4% yttrium oxide, 2% - 3% lanthanum oxide and 1% - 2% cerium oxide; 1% - 2% graphene; 0.6% - 1.2% nano hafnium carbide.

2. The wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding according to claim 1, wherein, The total atomic percentage of chromium, silicon and boron is 20% - 38%, and the atomic ratio of chromium to boron ≥ 5:

1.

3. A wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding according to claim 1, characterized in that, The ratio of the total mass of carbides to the total mass of nitrides and oxides is (3 - 5):(7 - 10).

4. A wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding and a preparation method thereof according to claim 1, characterized in that, Nano hafnium carbide is dispersed in the ceramic phase gaps in granular form, with a particle size ≤ 50 nm and a filling rate ≥ 90%.

5. A wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding according to claim 1, characterized in that, Graphene is dispersed in the metal matrix in a lamellar structure, with a sheet diameter of 1 - 10 μm and the number of layers ≤ 5 layers.

6. The wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding according to claim 1, wherein The hexagonal crystal form of boron nitride accounts for ≥ 95%, and the particle size ratio of silicon nitride to boron nitride is 1:0.5 - 1:

2.

7. The wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding according to claim 1, wherein, A C-O-M bonding layer is formed at the interface between graphene and the metal matrix, and the thickness of the bonding layer is 0.5 - 1.5 nm.

8. A preparation method of a wear-resistant, corrosion-resistant and high-temperature-resistant cermet composite material for laser cladding, characterized in that, Including the following steps: Step 1: Pretreatment of the metal matrix 1. Alloy selection: Select a nickel-based alloy or a cobalt-based alloy at 45% - 55% by mass percentage; 2. Atomic regulation: Precisely add 18% - 22% chromium, 4% - 7% silicon, 2% - 4% molybdenum and 3% - 6% boron to ensure that the chromium / boron atomic ratio ≥ 5:1, forming an antioxidant, heat corrosion-resistant and high-toughness matrix; Step 2: Preparation of intermetallic compounds and ceramic reinforcement phases 1. Intermetallic compound: Mix 1% - 3% nickel-aluminum intermetallic compound with 2% - 3% nickel-titanium intermetallic compound to enhance high-temperature strength and oxidation resistance; 2. Ceramic reinforcement phase: ①. Carbide: 5% - 10% tungsten carbide, 3% - 8% titanium carbide, 2% - 5% tantalum carbide, providing high hardness; ②. Nitride: 5% - 10% silicon nitride, 3% - 8% boron nitride, showing high-temperature stability and self-lubrication; ③. Oxide: 3% - 7% alumina, 3% - 5% zirconia, enhancing oxidation resistance and thermal shock resistance; 3. Ratio optimization: Control carbide:nitride + oxide = 3 - 5:7 - 10 to achieve a dynamic balance between hardness and toughness; Step 3: Additive design and interface regulation ①. Rare earth oxides: Add 2% - 4% yttrium oxide, 2% - 3% lanthanum oxide, 1% - 2% cerium oxide to refine grains and improve strength and toughness; ②. Graphene: Dispersed in the metal matrix with a sheet diameter of 1 - 10 μm and a structure of ≤5 layers to form a C-O-M bonding layer, enhancing thermal conductivity and thermal shock resistance; ③. Nano hafnium carbide: Particle size ≤50 nm, filling rate ≥90%, improving wear resistance and thermal shock resistance; ④. Boron nitride / silicon nitride: The proportion of hexagonal crystal form ≥95%, particle size ratio 1:0.5 - 1:2, constructing a low-friction and high-wear-resistant interface network; Step Four: Composite material forming and performance optimization 1. Laser cladding: Mix the pretreated metal matrix with the reinforcing phase and additives, and form a uniform composite layer through the laser cladding process; 2. Microstructure regulation: Utilize the interface pinning effect of nano hafnium carbide, the two-dimensional reinforcement mechanism of graphene, and the particle size gradient design of boron nitride / silicon nitride to achieve the synergistic improvement of the strength, toughness, wear resistance, and thermal stability of the material; 3. Performance verification: Through experimental tests, ensure that the material has long-term stability under extreme working conditions such as high temperature, high speed, and strong corrosion.

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