Silicon carbide-copper-nickel cermet composite material, and preparation method and application thereof

Abstract

This invention belongs to the field of metal-ceramic composite materials technology, and discloses a silicon carbide-copper-nickel metal-ceramic composite material, its preparation method, and its application. The composite material, by mass percentage, consists of 34%–88% silicon carbide ceramic phase, 5%–30% copper metal phase, 5%–30% nickel metal phase, 1%–5% interface modifier, and ≤1% unavoidable impurities. The interface modifier is at least one of TiO2, Al2O3, SiO2, Co, and C. The composite material has a density ≥95%, and the grain sizes of the silicon carbide and copper-nickel alloy phases are controlled at 30μm–60μm and 1μm–20μm, respectively. The preparation method includes mixing for 2–6 hours, various molding processes, sintering at 1800℃–2050℃ under vacuum / inert atmosphere for 2–4 hours, and post-treatment steps. The composite material of this invention has high hardness (≥2600HV), high toughness, excellent electrical and magnetic conductivity, and super thermal shock resistance. It can withstand ≥20 water quenching cycles at 1500℃ without cracking. The preparation process is suitable for industrial mass production and can be widely used in metallurgy, military industry, aerospace, new energy and other fields. It effectively solves the technical bottlenecks of existing silicon carbide-based metal ceramics, such as poor component adjustability, weak interfacial bonding and unbalanced comprehensive performance.

Description

Technical Field

[0001] This invention belongs to the field of metal-ceramic composite materials technology, specifically relating to a silicon carbide-copper-nickel metal-ceramic composite material that combines high hardness, high toughness, excellent electrical and magnetic conductivity, and superior thermal shock resistance. It also relates to the standardized preparation process of this composite material and its industrial applications in multiple fields, falling under the category of advanced ceramic matrix composite material preparation and application technology. Background Technology

[0002] Silicon carbide ceramics are currently the most widely used advanced structural ceramics in the industrial field. They possess ultra-high hardness second only to diamond, excellent wear and corrosion resistance, high-temperature oxidation resistance, and low density, making them irreplaceable in applications such as blast furnace components in metallurgy, bulletproof structures in military industry, heat-resistant components in aerospace, and high-temperature wear-resistant mechanical parts. However, pure silicon carbide ceramics are typical brittle materials with poor fracture toughness and weak impact resistance. They also lack electrical and magnetic conductivity and are difficult to process at high temperatures, making them unsuitable for complex and extreme working conditions, especially scenarios involving high temperature, high pressure, rapid heating and cooling, and electromagnetic coupling, which severely limits the further expansion of their application range.

[0003] Metal-ceramic composites, by introducing a metallic binder phase into a ceramic matrix, effectively combine the high hardness, high wear resistance, and high temperature resistance of ceramics with the high toughness and good electrical and thermal conductivity of metals, achieving synergistic complementarity of the two phases' properties and overcoming the performance shortcomings of single ceramic materials. Currently, there is some research on silicon carbide-copper-nickel system metal-ceramics, but several technical bottlenecks exist in practical applications: First, the component compatibility range is narrow, resulting in poor performance control flexibility and difficulty in adapting to the differentiated needs of different working conditions; second, the interfacial bonding between the ceramic and metal phases is weak, easily leading to defects such as interfacial pores, microcracks, and particle agglomeration, resulting in low material density; third, insufficient high-temperature stability and poor thermal shock resistance, unable to withstand rapid heating and cooling cycles from high temperature to room temperature, easily leading to cracking and deformation; fourth, unbalanced comprehensive performance, making it difficult to simultaneously achieve high hardness, high toughness, high compressive strength, and excellent electrical and magnetic conductivity, failing to meet the requirements of multi-scenario composite working conditions, and resulting in low feasibility for industrial mass production.

[0004] Based on the aforementioned deficiencies of existing technologies, a silicon carbide-copper-nickel cermet composite material with reasonable component ratio, uniform microstructure, dense interfacial bonding, excellent comprehensive performance, strong thermal shock resistance, tolerance to extreme rapid cooling and heating conditions, and mature process for easy industrial production is developed. This material breaks through existing technological bottlenecks, meets the core needs of high-end equipment manufacturing, military industry, aerospace, new energy and other fields, and has significant engineering application value and broad market prospects. Summary of the Invention

[0005] Purpose of the invention This invention addresses the technical problems of existing silicon carbide-based metal-ceramic composite materials, such as poor component tunability, weak interfacial bonding, low density, uneven overall performance, poor thermal shock resistance, insufficient high-temperature stability, and difficulty in industrial mass production. It provides a silicon carbide-copper-nickel metal-ceramic composite material, its preparation method, and its applications. By precisely optimizing the raw material composition ratio, controlling the microstructure, and optimizing the sintering process, this invention effectively improves the interfacial bonding between the ceramic and metal phases, significantly enhancing the material's density and overall mechanical properties. The material simultaneously possesses ultra-high hardness, excellent impact toughness, high compressive strength, excellent electrical and magnetic conductivity, and superior thermal shock resistance, enabling long-term stable use under extreme high-temperature conditions. Furthermore, the preparation process is simple and controllable, suitable for large-scale industrial production, and comprehensively covers application needs in metallurgy, military, aerospace, new energy induction heating, wireless charging, and other fields.

[0006] Technical solution To achieve the above-mentioned objectives, the technical solution disclosed in this invention is as follows:

[0007] The silicon carbide-copper-nickel cermet composite material of the present invention is composed of the following components by mass percentage, the total mass percentage of each component being 100%: Silicon carbide (SiC) ceramic phase: 34%~88%, as the core reinforcing phase and continuous skeleton of the material, provides ultra-high hardness, wear resistance and high temperature stability, and is the core component that ensures the overall structural strength and wear resistance and high temperature resistance of the material; Copper (Cu) metallic phase: 5%–30%, as the core component of the binder phase, effectively improves the overall toughness and electrical and thermal conductivity of the material, optimizes the interfacial compatibility between the ceramic phase and the metallic phase, and alleviates the brittle defects of the ceramic phase; Nickel (Ni) metal phase: 5%~30%, forming Cu-Ni alloy binder phase with copper, strengthening the interfacial bonding force between ceramic phase and metal phase, while significantly improving the high-temperature strength, oxidation resistance and magnetic permeability of the material, making up for the shortcomings of insufficient high-temperature stability of pure copper binder phase. Interface modification agent: 1% to 5%, wherein the interface modification agent is at least one or more composite modifiers selected from TiO2, Al2O3, SiO2, Co, and C, specifically used to improve the interfacial wettability between silicon carbide ceramic phase and copper-nickel alloy phase, eliminate defects such as interfacial pores, microcracks, and particle agglomeration, and improve the interfacial compactness of the two phases and the overall density of the material. Unavoidable impurities: ≤1%. Strictly control the impurity content in raw materials and during the preparation process to avoid impurities interfering with the formation of microstructure and ensure that the overall performance of the material meets the standards.

[0008] The composite material of this invention, after optimized preparation and densification sintering treatment, forms a uniform and stable densified dual-phase metallographic structure with no obvious structural defects. Its specific structural characteristics are as follows: Organizational morphology: The silicon carbide ceramic phase forms a continuous and interconnected three-dimensional skeleton structure, which is uniformly dispersed in the copper-nickel alloy bonding matrix. The two phases are tightly bonded at the interface, without obvious interface pores, separation cracks, particle agglomeration or phase debonding. The interface bonding strength is high, which ensures the balanced comprehensive performance of the material from the microstructure level. Grain size control: The average grain size of silicon carbide grains is controlled at 30μm to 60μm, the average grain size of copper-nickel alloy binder phase is controlled at 1μm to 20μm, the grain size ratio of ceramic phase and metal phase is reasonable, taking into account both hardness and toughness, and avoiding performance shortcomings caused by excessively large or small grains. Density: The relative density of the sintered composite material is ≥95%. High density can effectively avoid stress concentration caused by internal pores, and ensure that the core mechanical properties such as hardness, toughness and compressive strength of the material are stable and suitable for use in extreme working conditions.

[0009] The composite material of this invention has undergone performance testing, and its core indicators meet the following requirements, making it suitable for composite applications in multiple scenarios including mechanical, high-temperature, and electromagnetic environments: Mechanical properties: Hardness ≥2600HV, impact energy ≥3.5J / cm², fracture toughness KIC ≥6.5MPa·m^1 / 2, compressive strength ≥700MPa; Electromagnetic properties: Excellent electrical and magnetic conductivity, capable of efficiently coupling alternating magnetic fields, stably realizing inductive heating and inductive power extraction functions, breaking through the limitation of traditional silicon carbide ceramics having no electromagnetic properties; Thermal shock resistance: It can withstand ≥20 cycles of rapid cooling and heating in water quenching from 1500℃ to room temperature without cracking, peeling, or deformation; Operating condition adaptability: Under the impact of various cooling media such as air cooling, water cooling, and oil cooling, the structure has excellent stability and no cracking, deformation, or surface peeling problems. It can be used for a long time under extreme conditions of rapid cooling and heating.

[0010] Table 1

[0011] As shown in Table 1, although pure silicon carbide ceramics possess ultra-high compressive strength and hardness, they are brittle, have poor toughness, poor thermal shock resistance, and lack electrical and magnetic conductivity. In practical applications, they are prone to instantaneous brittle fracture, limiting their applicability. Ordinary steel and cast iron materials have good toughness and are easy to process, but their compressive strength, hardness, and high-temperature resistance are severely insufficient, making them unsuitable for extreme high-temperature conditions. The silicon carbide-copper-nickel cermet composite material described in this invention has a compressive strength of 700–900 MPa, while also possessing high hardness, high fracture toughness, excellent thermal shock resistance, electrical and magnetic conductivity, and high-temperature resistance. It comprehensively overcomes the performance defects of existing single materials and similar composite materials, exhibiting outstanding substantive characteristics and significant technological advancements.

[0012] The composite material preparation process of this invention is mature and controllable, requiring no special, complex, or high-end equipment. The process parameters are compatible with existing industrial production equipment, enabling large-scale industrial production. Specifically, it includes the following four standardized steps: Mixing process: Weigh silicon carbide powder, copper powder, nickel powder and interface modifier according to the above mass percentages, and put all raw materials into the mixing equipment at the same time. Mix for 2 to 6 hours, and control the mixing speed and environment throughout the process to ensure that the powder components are fully mixed, without particle agglomeration or segregation, and finally obtain a uniformly dispersed mixed powder. Molding process: Based on the structural shape, size and precision requirements of the subsequent product, at least one of the following processes is selected: dry pressing, cold pressing, hot pressing, warm pressing, slurry injection, injection molding, and 3D printing. The uniformly mixed powder is prepared into a green body of the preset shape and size to ensure that the green body has a complete structure, uniform density and no delamination or cracking defects. Sintering process: The formed green body is placed in a vacuum sintering furnace or an atmosphere-protected sintering furnace. Under vacuum or inert atmosphere protection such as argon or nitrogen, the temperature is raised to 1800℃~2050℃ at a uniform rate and held for sintering for 2~4 hours to complete the densification sintering of the material and the bonding reaction of the ceramic phase-metal phase interface. Then, it is naturally cooled to room temperature with the furnace to obtain a dense sintered green body. Post-processing: Based on the actual product precision, surface finish and dimensional tolerance requirements, the sintered blank is subjected to fine grinding, polishing or conventional machining to finally obtain silicon carbide-copper-nickel metal ceramic composite components with accurate dimensions, smooth surface and qualified performance. Attached Figure Description

[0013] Figure 1 The image shows the internal metallographic microstructure of the silicon carbide-copper-nickel cermet composite material described in Example 2 of this invention, wherein: • The black area is a continuously distributed three-dimensional silicon carbide (SiC) ceramic reinforcing phase, which constitutes the skeleton structure of the material and provides high hardness, high wear resistance and high temperature resistance. • The yellowish-gray area is a copper-nickel (Cu-Ni) alloy binder phase that is uniformly filled in the gaps between the ceramic skeleton, which plays a role in toughening, electrical conductivity and magnetic permeability; • The two-phase interface is tightly bonded, with no obvious pores, cracks or debonding, ensuring the material's excellent comprehensive mechanical properties and thermal shock resistance.

[0014] Beneficial effects Compared with existing silicon carbide composite materials, this invention has the following outstanding advantages, comprehensively solves the bottlenecks of existing technologies, and has extremely strong industrial application value: With strong component adjustability, it can adapt to the differentiated needs of multiple scenarios: the raw material composition ratio range is wide, and the mass ratio of silicon carbide, copper and nickel can be flexibly adjusted according to the performance emphasis of different working conditions, so as to prepare a variety of differentiated materials such as high conductivity and magnetic permeability, ultra-high wear resistance, high temperature stability, bulletproof protection and comprehensive balance, which can be precisely adapted to the application requirements of different fields. Excellent interface bonding and high material density: By adding special interface modifiers, the interfacial wettability between the ceramic phase and the metal phase is greatly optimized, and common defects such as interface pores, microcracks and phase debonding are completely solved. The material has a relative density of ≥95%, stable and reliable mechanical properties, no local performance weaknesses, and a longer service life. Excellent comprehensive mechanical properties: It perfectly integrates the high hardness and high wear resistance of the ceramic phase with the high toughness and high compressive strength of the metallic phase. Its core mechanical properties far exceed those of conventional composite materials. It has outstanding resistance to deformation and breakage under high pressure load and impact load, overcoming the core shortcoming of brittle fracture of pure silicon carbide ceramics. Unique electrical and magnetic properties broaden application scenarios: Breaking through the technical limitations of pure silicon carbide ceramics being non-conductive and non-magnetic, the material is endowed with excellent electrical and magnetic properties, enabling electromagnetic induction coupling, induction heating, and wireless power generation, successfully broadening the application of the material in emerging fields such as new energy induction heating and wireless charging. Top-notch high temperature resistance and thermal shock resistance: It can withstand 1500℃ high temperature for a long time, and 1800℃ high temperature for an instant. It also has excellent resistance to rapid heating and cooling. It can withstand more than 20 water quenching cycles from 1500℃ to room temperature without cracking. It is perfectly suited for extreme high temperature working conditions such as metallurgy and aerospace. The technology is mature and has high feasibility for industrial mass production: the preparation process is simple, the sintering temperature range is controllable, no special customized equipment is required, and the entire process of mixing, molding, sintering and post-processing is compatible with existing industrial production equipment. The process parameters are stable and can achieve large-scale standardized mass production. With a wide range of applications and broad market prospects, it can be widely used in metallurgical high-temperature components, military bulletproof structures, aerospace heat-resistant components, induction heating elements, wireless charging equipment, high-end wear-resistant conductive and magnetic components, and other fields. Its application scenarios fully cover the core national tracks such as high-end manufacturing, military industry, new energy, and aerospace. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to specific embodiments. The embodiments are only used to specifically illustrate the technical solutions of the present invention and do not limit the scope of protection of the present invention. Non-creative improvements made by those skilled in the art based on the core technical solutions of the present invention are all within the scope of protection of the present invention.

[0016] Example 1 Low-carbon silicon carbide, high conductivity, magnetic permeability, and high toughness composition (mass percentage): silicon carbide 38%, copper 28%, nickel 29%, TiO2-Al2O3-Co composite interface modifier 4%, unavoidable impurities ≤1%.

[0017] Preparation process: After accurately weighing each component according to the ratio, put them into the mixing equipment and stir for 4 hours; adopt cold pressing molding process with molding pressure of 30MPa; place the green blank in a vacuum sintering furnace, control the vacuum degree ≤10-²Pa, heat it at a uniform rate to 2050℃, and hold it for 3 hours to complete densification sintering; after cooling to room temperature in the furnace, it is finely ground and polished to obtain composite material components.

[0018] Performance test results: density 97.2%, hardness 2650HV, impact energy 4.4J / cm², fracture toughness 7.4MPa·m^1 / 2, compressive strength 830MPa; no cracking, deformation, or peeling after ≥25 cycles of water quenching at 1500℃; microstructure shows dense bonding between the two phases, with no pores, cracks, or debonding, exhibiting excellent electrical and magnetic conductivity, suitable for scenarios with high requirements for electrical and magnetic conductivity.

[0019] Example 2: Composition of silicon carbide with balanced overall performance (mass percentage): 60% silicon carbide, 17% copper, 19% nickel, 3% SiO2-TiO2-Co composite interface modifier, and ≤1% unavoidable impurities.

[0020] Preparation process: All raw materials are accurately weighed according to the formula and stirred for 4 hours; a warm pressing process is adopted with a molding pressure of 25MPa; the temperature is uniformly raised to 1900℃ under a vacuum atmosphere and held for 4 hours to complete sintering; after cooling in the furnace, polishing is performed to obtain the finished composite material.

[0021] Performance test results: density 96.9%, hardness 2800HV, impact energy 4.0J / cm², fracture toughness 7.0MPa·m^1 / 2, compressive strength 800MPa; no cracking after ≥20 cycles of water quenching at 1500℃; strong bonding between ceramic and metal phases; balanced and qualified hardness, toughness, high temperature resistance, electrical conductivity and magnetic permeability; extremely versatile and suitable for most conventional and moderately extreme working conditions.

[0022] Example 3: Composition of high silicon carbide, ultra-high hardness, wear-resistant component (mass percentage): silicon carbide 85%, copper 5%, nickel 5%, Co-Al2O3 composite interface modifier 4%, unavoidable impurities ≤1%.

[0023] Preparation process: Mix all raw materials according to the formula and stir for 5 hours; adopt hot pressing molding process; under the protection of argon inert atmosphere, heat up to 1950℃ at a uniform rate and hold for 3 hours to complete sintering; after cooling in the furnace, shape by conventional machining to obtain the final component.

[0024] It has a density of 96.6%, a hardness of 2980HV, an impact energy of 3.5J / cm², a fracture toughness of 6.5MPa·m^1 / 2, and a compressive strength of 790MPa; it can withstand ≥20 water quenching cycles at 1500℃ without cracking; it has a dense interface bond, excellent high-temperature stability, and wear resistance far exceeding that of conventional similar materials, making it suitable for extreme working conditions requiring high wear resistance and high hardness.

Claims

1. A silicon carbide-copper-nickel cermet composite material, characterized in that, By mass percentage, it consists of the following components: 34%–88% silicon carbide ceramic phase; 5%–30% copper; 5%–30% nickel; 1%–5% interface modifier; unavoidable impurities ≤1%; the total mass percentage of all components is 100%.

2. The silicon carbide-copper-nickel cermet composite material according to claim 1, characterized in that, The interface modification agent is at least one or more composite modifiers selected from TiO2, Al2O3, SiO2, Co, and C.

3. The silicon carbide-copper-nickel cermet composite material according to claim 1, characterized in that, The material has a dense two-phase structure, with silicon carbide forming a continuous three-dimensional skeleton structure and copper-nickel alloy phase uniformly filling the gaps in the skeleton. The two-phase interface is densely bonded without pores, cracks, debonding, or particle agglomeration.

4. The silicon carbide-copper-nickel cermet composite material according to claim 1, characterized in that, The silicon carbide grain size is 30μm to 60μm, the copper-nickel alloy phase grain size is 1μm to 20μm, and the composite material density is ≥95%.

5. The silicon carbide-copper-nickel cermet composite material according to any one of claims 1 to 4, characterized in that, The material properties meet the following requirements: hardness ≥2600HV; impact energy ≥3.5J / cm²; fracture toughness KIC ≥6.5MPa·m^1 / 2; compressive strength ≥700MPa; excellent electrical and magnetic conductivity; and can withstand ≥20 water quenching cycles from 1500℃ to room temperature without cracking.

6. The silicon carbide-copper-nickel cermet composite material according to claim 1, characterized in that, The composition is: 38% silicon carbide, 28% copper, 29% nickel, and 4% composite interface modifier.

7. The silicon carbide-copper-nickel cermet composite material according to claim 1, characterized in that, The composition is: 60% silicon carbide, 17% copper, 19% nickel, and 3% composite interface modifier.

8. The silicon carbide-copper-nickel cermet composite material according to claim 1, characterized in that, The composition is: 85% silicon carbide, 5% copper, 5% nickel, and 4% composite interface modifier.

9. A method for preparing the silicon carbide-copper-nickel cermet composite material according to any one of claims 1 to 8, characterized in that, include: Mixing for 2–6 hours; molding by at least one of the following methods: dry pressing, cold pressing, hot pressing, warm pressing, grouting, injection molding, gel casting, or 3D printing; sintering at 1800℃–2050℃ for 2–4 hours under vacuum or inert atmosphere; post-processing to obtain composite components.

10. The application of the silicon carbide-copper-nickel cermet composite material according to any one of claims 1 to 8 in the preparation of metallurgical high-temperature components, military bulletproof components, aerospace heat-resistant components, induction heating elements, wireless charging devices, or high-end wear-resistant conductive and magnetic components.

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