High-entropy particle reinforced heat-resistant copper alloy, preparation method and application thereof

Abstract

The application provides a high-entropy particle reinforced heat-resistant copper alloy, a preparation method and application thereof. The high-entropy particle reinforced heat-resistant copper alloy comprises a copper matrix phase and FeCoNiCrSi high-entropy particle phases dispersed in the copper matrix phase; and the chemical formula of the high-entropy particle reinforced heat-resistant copper alloy is (Fe a Co b Ni c Cr d Si e ) x Cu 100‑x , wherein a is 15-30, b is 25-45, c is 1-5, d is 10-20, e is 10-40, and x is 4-6. In the copper alloy, the FeCoNiCrSi high-entropy particle phase serves as a reinforcing core, effectively prevents dislocation movement through dislocation pinning effect, significantly improves the mechanical strength of the obtained copper alloy, minimizes the stress generated by lattice mismatch to ensure the toughness of the obtained alloy, prevents high-temperature creep of the copper alloy, and significantly improves the heat resistance of the copper alloy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of copper alloys, in particular, to a high-entropy particle reinforced heat-resistant copper alloy, a preparation method and application thereof. BACKGROUND

[0002] Copper-based materials play an irreplaceable role in key industrial fields such as electronics, electric power, aerospace, etc. due to their excellent electrical and thermal conductivity. Traditional copper alloys introduce a small amount of alloying elements such as zinc, tin, nickel, iron, etc. to improve their strength and corrosion resistance, but this addition often comes at the expense of electrical conductivity, limiting its performance in applications requiring high strength and high electrical conductivity. To overcome this contradiction, in recent years, high-entropy alloys (HEAs) as a new type of material system have received widespread attention due to their unique properties and effects. HEAs are usually composed of five or more than five metal elements in equal or near-equal molar ratios, exhibiting superior corrosion resistance, wear resistance, plasticity and strength compared to traditional alloys.

[0003] However, introducing HEAs into copper-based materials to achieve a synergistic improvement in high strength and high electrical conductivity faces many challenges. Traditional precipitation strengthened copper alloys, such as Cu-Fe-P system, Cu-Ni-Si system, Cu-Cr-Zr system, etc., their strengthening mechanism mainly depends on the lattice mismatch between the precipitates and the copper matrix. However, a larger lattice mismatch (usually more than 5%) often leads to a significant increase in nucleation resistance of precipitates and a decrease in precipitate density, which not only affects the mechanical properties of the material, but also easily causes grain boundary sliding and micro-crack propagation at high temperatures, reducing the thermal stability of the material.

[0004] In addition, the preparation methods of high-entropy materials, such as vacuum arc melting, powder metallurgy, sputtering deposition, etc., also play a decisive role in the microstructure and final performance of the material. Among them, the vacuum arc melting technology is widely used because it can accurately control the composition of the material and prepare high-quality alloy ingots. However, how to uniformly distribute high-entropy particles in copper-based materials, and how to control the size, morphology and distribution of precipitates through reasonable heat treatment processes such as solid solution, rolling, recrystallization annealing and aging treatment, are important issues faced by researchers.

[0005] Therefore, based on the formation mechanism of high-entropy particles and the mechanism of action with the matrix alloy, how to provide a copper-based alloy material that not only has high mechanical properties, but also can maintain high strength and thermal stability at high temperatures, is one of the important technical problems to be solved in the field. SUMMARY

[0006] The main objective of this invention is to provide a high-entropy particle-reinforced heat-resistant copper alloy, its preparation method, and its application, so as to solve the problem that high-entropy particle-reinforced copper alloys in the prior art are difficult to possess both high mechanical properties and high heat resistance due to severe lattice mismatch.

[0007] To achieve the above objectives, a first aspect of the present invention provides a high-entropy particle-reinforced heat-resistant copper alloy comprising a copper matrix phase and a FeCoNiCrSi-based high-entropy particle phase dispersed in the copper matrix phase; and the chemical formula of the high-entropy particle-reinforced heat-resistant copper alloy is (Fe... a Co b Ni c Cr d Si e ) x Cu 100-x Where a is 15~30, b is 25~45, c is 1~5, d is 10~20, e is 10~40, and x is 4~6.

[0008] Furthermore, the FeCoNiCrSi system high-entropy particle phase and the copper matrix phase are coherent, and the particle size of the FeCoNiCrSi system high-entropy particle phase is 5nm~50nm.

[0009] Furthermore, in the chemical formula of the high-entropy particle-reinforced heat-resistant copper alloy, a is 18~26, b is 28~41, c is 4~5, d is 10~16, e is 12~40, and x is 4~5.5.

[0010] Furthermore, the yield strength of the high-entropy particle-reinforced heat-resistant copper alloy is 400 MPa to 500 MPa; and / or, the tensile strength of the high-entropy particle-reinforced heat-resistant copper alloy is 400 MPa to 550 MPa; and / or, the tensile strain of the high-entropy particle-reinforced heat-resistant copper alloy is 10% to 20%; and / or, the electrical conductivity of the high-entropy particle-reinforced heat-resistant copper alloy is 60% IACS to 75% IACS; and / or, the softening temperature of the high-entropy particle-reinforced heat-resistant copper alloy is 550℃ to 600℃.

[0011] A second aspect of the present invention provides a method for preparing the above-mentioned high-entropy particle-reinforced heat-resistant copper alloy, comprising: step S1, preparing raw materials according to the chemical formula of the high-entropy particle-reinforced heat-resistant copper alloy; step S2, refining a FeCoNiCrSi system high-entropy particle phase precursor alloy by vacuum arc melting; the precursor alloy and copper raw materials are successively melted and vacuum cast to obtain an ingot; step S3, performing a solution treatment on the ingot at a temperature of 1000±100℃ under a protective atmosphere with a pressure of 0.05±0.001MPa to obtain a first billet; step S4 Step S5: The first billet is subjected to a first cold rolling to obtain a second billet; Step S6: The second billet is subjected to annealing treatment at a temperature of 600℃~800℃ under a protective atmosphere with a pressure of 0.05±0.001MPa to obtain a third billet; Step S7: The third billet is subjected to a second cold rolling to obtain a fourth billet; Step S8: The fourth billet is subjected to aging treatment at a temperature of 250℃~550℃ under a protective atmosphere with a pressure of 0.05±0.001MPa to allow the FeCoNiCrSi system high-entropy particle phase to precipitate in situ, thereby obtaining a high-entropy particle-reinforced heat-resistant copper alloy.

[0012] Furthermore, in step S3, the solution treatment time is 1h to 4h.

[0013] Furthermore, in step S5, the annealing time is 0.5h to 3h.

[0014] Furthermore, in step S7, the time for aging processing is 1 hour to 24 hours.

[0015] Furthermore, the protective atmosphere in steps S3, S5, and S7 is argon; and / or, the reduction amount of the first cold roll and the second cold roll is independently 30% to 60%.

[0016] A third aspect of the present invention provides an application of the above-mentioned high-entropy particle-reinforced heat-resistant copper alloy as an alloy material in the aerospace, transportation, or industrial manufacturing fields.

[0017] By applying the technical solution of this invention, a copper alloy with a special composition and containing a FeCoNiCrSi system high-entropy particle phase is designed through the synergistic effect of multiple alloying elements, which greatly enhances the mechanical properties and heat resistance of the copper alloy. The FeCoNiCrSi system high-entropy particle phase, acting as a reinforcing core, effectively prevents dislocation movement through dislocation pinning, significantly improving the mechanical strength of the resulting copper alloy. It also ensures the toughness of the alloy by minimizing the stress generated by lattice mismatch, while simultaneously preventing high-temperature creep and significantly improving its heat resistance. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0019] Figure 1 This is a tensile stress-strain curve of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 1 of the present invention.

[0020] Figure 2 The image shows the scanning electron microscope (SEM) characterization results of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 1 of this invention.

[0021] Figure 3 The image shows the energy dispersive spectroscopy (EDS) test results of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 1 of this invention.

[0022] Figure 4 This is a high-angle annular dark field image (HAADF) characterization result of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 1 of the present invention;

[0023] Figure 5 This is a graph showing the softening temperature test results of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 1 of this invention.

[0024] Figure 6 This is a tensile stress-strain curve of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 2 of the present invention.

[0025] Figure 7 The image shows the SEM characterization results of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 2 of this invention.

[0026] Figure 8 The image shows the EDS test results of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 2 of this invention.

[0027] Figure 9 The figure shows the HAADF characterization results of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 2 of this invention.

[0028] Figure 10 This is a graph showing the softening temperature test curve of the high-entropy particle-reinforced heat-resistant copper alloy obtained in Example 2 of the present invention. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the embodiments.

[0030] As described in the background section, existing high-entropy particle-reinforced copper alloys suffer from severe lattice mismatch issues, making it difficult to simultaneously possess both high mechanical properties and high heat resistance. To address these technical problems, a first aspect of this invention provides a high-entropy particle-reinforced heat-resistant copper alloy comprising a copper matrix phase and a FeCoNiCrSi-based high-entropy particle phase dispersed within the copper matrix phase; and the chemical formula of the high-entropy particle-reinforced heat-resistant copper alloy is (Fe... a Co b Ni c Cr d Si e ) x Cu 100-x Where a is 15~30, b is 25~45, c is 1~5, d is 10~20, e is 10~40, and x is 4~6.

[0031] This invention utilizes the synergistic effect of multiple alloying elements to design a copper alloy with a unique composition and containing high-entropy FeCoNiCrSi phase particles, significantly enhancing the mechanical properties and heat resistance of the copper alloy. Specifically, this invention addresses the core technical bottlenecks of traditional precipitation-strengthened copper alloys, such as high lattice mismatch between precipitates and the matrix (>5%), high nucleation resistance, and low precipitation density. It employs Fe with a face-centered cubic structure... a Co b Ni c Cr d Si e (a+b+c+d+e=100) High-entropy nanoparticles, acting as precipitates, exhibit a lattice constant that better matches the copper matrix (~0.36147nm), significantly reducing the nucleation barrier and increasing the nucleation rate. Solid solution-strengthened cores are constructed through the high-entropy effect (≥12Rln6), and a dislocation pinning network is formed by combining the lattice distortion effect (strain <0.8%), effectively preventing dislocation movement and significantly improving the mechanical strength of the resulting copper alloy. Minimizing the stress generated by lattice mismatch ensures the toughness of the alloy while preventing high-temperature creep, significantly improving its heat resistance. Ultimately, a high-entropy particle-reinforced copper alloy (hereinafter referred to as "copper alloy") that balances high mechanical strength, high toughness, high electrical conductivity, and high heat resistance is obtained.

[0032] Furthermore, the FeCoNiCrSi high-entropy particle phase and the copper matrix phase are coherent, and the particle size of the FeCoNiCrSi high-entropy particle phase is 5nm~50nm. That is to say, in the copper alloy crystal structure provided by this invention, because the lattice constant of the FeCoNiCrSi high-entropy particle phase is better compatible with the copper matrix, the two crystals exhibit a coherent relationship, thereby more effectively improving the comprehensive mechanical properties of the resulting copper alloy material. The aforementioned preferred particle size can more effectively pin dislocations, increasing yield strength. Simultaneously, thanks to the reduced nucleation resistance due to the coherent effect, the FeCoNiCrSi high-entropy particle phase particles can exhibit a higher density distribution in the copper matrix phase, further enhancing the overall strength of the resulting high-entropy particle-reinforced heat-resistant copper alloy. Moreover, the coherent high-entropy alloy particles of the aforementioned particle size can more significantly suppress grain boundary slip, slowing down the softening rate of the resulting copper alloy at high temperatures, thereby further improving its heat resistance.

[0033] In several preferred embodiments, the lattice constant of the FeCoNiCrSi-based high-entropy particle phase is preferably 0.351 nm to 0.357 nm; and the lattice mismatch between the FeCoNiCrSi-based high-entropy particle phase and the copper matrix phase is preferably 0.05% to 0.3%. The aforementioned preferred lattice constant of the FeCoNiCrSi-based high-entropy particle phase and its lattice mismatch with the copper matrix phase mean that the internal stress caused by the lattice mismatch is smaller, and the interface between the FeCoNiCrSi-based high-entropy particles and the copper matrix is ​​more stable, thereby reducing the probability of microcracks and further improving the mechanical properties of the resulting copper alloy. Simultaneously, the aforementioned preferred structural parameters also help maintain the lattice integrity around the FeCoNiCrSi-based high-entropy particles, reducing lattice defects, thereby further improving the heat resistance of the resulting copper alloy and promoting higher performance stability during long-term operation.

[0034] In the elemental composition of the aforementioned high-entropy particle-reinforced heat-resistant copper alloy, the Fe and Co content can improve the tensile strength of the resulting copper alloy, while an appropriate Si content is beneficial to improving the alloy's oxidation resistance and thermal stability, thereby maintaining excellent mechanical properties under high-temperature service conditions. Furthermore, adjusting the Cr and Ni content can improve the material's toughness, ensuring it is not easily fractured under impact loads. Therefore, to further synergistically enhance the mechanical strength and heat resistance of the resulting high-entropy particle-reinforced heat-resistant copper alloy, and to promote a more precise structural match between the FeCoNiCrSi system of high-entropy particles and the copper matrix, the preferred chemical formula has a value of a = 18-26, b = 28-41, c = 4-5, d = 10-16, e = 12-40, and x = 4-5.5; more preferably, a = 20-23, b = 30-35, c = 4-5, d = 13-15, e = 20-30, and x = 4.5-5.

[0035] Furthermore, the chemical formula of the high-entropy particle-reinforced heat-resistant copper alloy is (Fe 26 Co 41 Ni5Cr 16 Si 12 )4Cu 96 、(Fe 23 Co 35 Ni5Cr 14 Si 23 ) 4.5 Cu 95.5 、(Fe 21 Co 34 Ni5Cr 13 Si 27 5Cu 95 , or (Fe 18 Co 28 Ni4Cr 10 Si 40 ) 5.5 Cu 94.5 Through extensive experimentation, the inventors obtained the chemical formula of the aforementioned preferred FeCoNiCrSi system high-entropy particle-reinforced heat-resistant copper alloy. In the crystal structure of this copper alloy with the specific chemical formula, the high-entropy particles can better bond with the copper matrix, thus more significantly leveraging the beneficial effects of the coherent strengthening mechanism. Especially (Fe... 23 Co 35 Ni5Cr 14 Si 23 ) 4.5 Cu 95.5 and (Fe) 21 Co 34 Ni5Cr 13 Si 27 5Cu 95 In copper alloys with these two chemical formulas, the FeCoNiCrSi system high-entropy particle phase can achieve a more precise coherent match with the copper matrix, thereby significantly optimizing the crystal structure and metallographic structure of the resulting copper alloy, ultimately yielding a high-entropy particle-reinforced heat-resistant copper alloy with both higher mechanical properties and higher heat resistance.

[0036] In several preferred embodiments, the yield strength of the high-entropy particle-reinforced heat-resistant copper alloy is 400 MPa to 500 MPa; and / or, the tensile strength is 400 MPa to 550 MPa; and / or, the tensile strain is 10% to 20%; and / or, the electrical conductivity is 60% IACS to 75% IACS; and / or, the softening temperature is 550°C to 600°C. That is to say, the high-entropy particle-reinforced heat-resistant copper alloy provided by this invention, benefiting from the precise design of its elemental composition and the coherent strengthening mechanism in its crystal structure, exhibits particularly superior mechanical properties, electrical conductivity, and heat resistance.

[0037] The second aspect of the present invention provides a method for preparing the above-mentioned high-entropy particle-reinforced heat-resistant copper alloy, comprising: step S1, preparing raw materials according to the chemical formula of the high-entropy particle-reinforced heat-resistant copper alloy; step S2, refining a FeCoNiCrSi system high-entropy particle phase precursor alloy by vacuum arc melting; the precursor alloy and copper raw materials are successively melted and vacuum cast to obtain an ingot; step S3, under a protective atmosphere with a pressure of 0.05±0.001MPa, the ingot is subjected to a solution treatment at a temperature of 1000±100℃ to obtain a first billet; step S4, the first billet is subjected to a first cold rolling to obtain a second billet; step S5, under a protective atmosphere with a pressure of 0.05±0.001MPa, the second billet is subjected to a temperature of 600℃~800℃. The annealing process yields a third billet; in step S6, the third billet undergoes a second cold rolling process to obtain a fourth billet; in step S7, the fourth billet is subjected to an aging treatment at a temperature of 250℃~550℃ under a protective atmosphere with a pressure of 0.05±0.001MPa to allow the high-entropy particle phase of the FeCoNiCrSi system to precipitate in situ, thereby obtaining a high-entropy particle-reinforced heat-resistant copper alloy.

[0038] In response to the aforementioned high-entropy particle-reinforced heat-resistant copper alloy, this invention provides a corresponding preparation method, which promotes Fe... a Co b Ni c Cr d Si eHigh-entropy particles are generated in situ within the copper matrix, resulting in finer particle sizes, more dispersed distribution, and better coherence with the copper matrix lattice. Furthermore, the vacuum arc melting casting method employed in the refining process simplifies and improves efficiency. Specifically, in the above preparation process, after batching, vacuum arc melting technology is used to form a low-impurity, low-porosity, and well-integrated FeCoNiCrSi-based high-entropy particle phase, creating prerequisites for the uniform precipitation of high-entropy particles in subsequent steps. Then, in step S3, the solution treatment is performed in a protective atmosphere at a precise temperature range of 1000±100℃. This aims to dissolve and stabilize the high-entropy particle composition in the precursor alloy, allowing it to fully integrate into the copper matrix and form a solid solution, laying the groundwork for the effective formation of subsequent precipitates. The annealing treatment following the first cold rolling is also performed in a protective atmosphere at a temperature range of 600℃~800℃, promoting recrystallization within the alloy and restoring the lattice structure damaged by cold rolling. Following the second cold rolling, high-entropy particles were precipitated through aging treatment, while their size and distribution were further optimized, resulting in a uniformly distributed nanoscale coherent precipitate phase within the copper matrix. Ultimately, this significantly improved the mechanical strength of the high-entropy particle-reinforced heat-resistant copper alloy. Furthermore, the in-situ precipitation further reduced the lattice mismatch, achieving a dual improvement in both the strength and heat resistance of the resulting copper alloy.

[0039] In step S3, the solution treatment time is further optimized to be 1 to 4 hours. If the treatment time is too short, the dissolution and diffusion between elements may be incomplete, leading to uneven distribution of high-entropy particles and adversely affecting the overall performance of the final copper alloy. Conversely, if the time is too long, element burn-off may occur. Therefore, the optimal solution treatment time is chosen to more thoroughly dissolve the elements in the alloy, eliminate grain boundaries, form a more stable solid solution state, and reduce intragranular strain. Ultimately, this significantly optimizes the crystal structure and metallographic structure of the resulting high-entropy particle-reinforced heat-resistant copper alloy, improving its various properties.

[0040] In step S5, the annealing time is preferably 0.5h to 3h to more effectively restore the crystal structure and promote the more ordered growth of FeCoNiCrSi system high-entropy particles as in-situ precipitates. At the same time, this annealing time further refines the grain structure of the alloy, thereby significantly improving the toughness and high strength of the final copper alloy.

[0041] In step S7, the aging treatment time is preferably 1h to 24h, so as to more effectively control the growth process of high-entropy particles and promote the formation of a more uniformly distributed nanoscale coherent phase in the copper matrix; and, this aging time can also effectively promote phase transformation, so that the microstructure inside the high-entropy particle-enhanced heat-resistant copper alloy reaches a more stable state, thereby enhancing its hardness and strength.

[0042] Furthermore, to better reduce oxidation contamination and improve the purity of the resulting copper alloy microstructure, it is preferable that the protective atmosphere in steps S3, S5, and S7 is argon. In practical applications, the pressure and gas environment in steps S3, S5, and S7 are all achieved through vacuum sealing.

[0043] In several typical implementations, the reduction amount of the first cold rolling and the second cold rolling is independently 30% to 60%. The above-mentioned reduction amount is preferred during the two cold rolling processes to better coordinate with the heat treatment conditions. This promotes grain refinement and increases dislocation density, creating more favorable conditions for the uniform precipitation of high-entropy particles in subsequent annealing and aging treatments, ultimately significantly optimizing the overall performance of the high-entropy particle-reinforced heat-resistant copper alloy.

[0044] A third aspect of this invention provides an application of the aforementioned high-entropy particle-reinforced heat-resistant copper alloy as an alloy material in the aerospace, transportation, or industrial manufacturing fields. The aforementioned high-entropy particle-reinforced heat-resistant copper alloy, through in-situ formed nanoscale coherent precipitates with specific elemental compositions, not only significantly improves the mechanical strength of the copper alloy but also promotes superior heat resistance, thereby effectively meeting the stringent performance requirements of various industrial sectors for alloy materials.

[0045] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0046] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0047] Example 1

[0048] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0049] (1) According to (Fe) 23 Co 35 Ni5Cr 14 Si 23 ) 4.5 Cu 95.5 The chemical formula for this alloy is as follows: using an SDPTOP-FA2004 electronic balance, the following raw materials were weighed: Fe: 0.918 g, Co: 1.475 g, Ni: 0.21 g, Cr: 0.52 g, Si: 0.462 g, Cu: 96.415 g.

[0050] (2) Melting and casting: Fe is first refined using vacuum arc melting. 23 Co 35 Ni5Cr 14 Si 23 Pre-alloying, then Fe 23 Co 35 Ni5Cr 14 Si 23 The pre-alloyed and high-purity copper are melted together and repeatedly melted 12 times, then vacuum-cast to obtain an ingot.

[0051] (3) Vacuum sealing of the ingot, filling it with argon gas at 0.05 MPa to provide a protective atmosphere at 0.05 MPa, and solidifying it in a box-type resistance furnace at 1000 ℃ for 1 h, followed by water quenching to obtain the first billet.

[0052] (4) One-pass rolling: The first billet is subjected to multiple cold rolling passes with a total reduction of 40% to obtain the second billet;

[0053] (5) Recrystallization annealing: The second billet is vacuum sealed and filled with argon gas at 0.05 MPa, which provides a protective atmosphere at a pressure of 0.05 MPa. The billet is then recrystallized and annealed at 700 °C for 1 h to obtain the third billet.

[0054] (6) Secondary rolling: The third billet is subjected to multiple cold rolling passes with a total reduction of 50% to obtain the fourth billet;

[0055] (7) Aging: The fourth billet is vacuum sealed and filled with argon gas at 0.05 MPa, which provides a protective atmosphere at a pressure of 0.05 MPa. It is then aged at 450 °C for 24 h in a box-type resistance furnace to obtain FeCoNiCrSi system high-entropy particle-reinforced heat-resistant copper alloy.

[0056] The mechanical properties of the obtained high-entropy particle-reinforced heat-resistant copper alloy were tested, and the room temperature tensile stress-strain curves are shown below. Figure 1 .

[0057] The obtained high-entropy particle-reinforced heat-resistant copper alloy was characterized by SEM. The SEM characterization results are shown in the figure. Figure 2 ;Depend on Figure 2 It can be seen that the obtained high-entropy particle-reinforced heat-resistant copper alloy includes a copper matrix and a nano-precipitated phase (i.e., FeCoNiCrSi system high-entropy particle phase) dispersed in the copper matrix, and the precipitated phase is uniformly distributed in the copper matrix.

[0058] The obtained high-entropy particle-reinforced heat-resistant copper alloy was subjected to EDS energy dispersive spectroscopy, and the EDS characterization results are shown in the figure. Figure 3 .Depend on Figure 3It can be seen that the nano-precipitated phase is composed of Fe, Co, Ni, Cr and Si, that is, the FeCoNiCrSi system high-entropy particle phase is generated in situ in the copper matrix.

[0059] The obtained high-entropy particle-reinforced heat-resistant copper alloy was characterized by HAADF testing, and the HAADF characterization results are shown below. Figure 4 .Depend on Figure 4 It can be seen that the high-entropy particle phase crystal and the copper matrix phase crystal of the FeCoNiCrSi system exhibit a coherent relationship.

[0060] The softening temperature curve of the obtained high-entropy particle-reinforced heat-resistant copper alloy was tested, and the obtained curve is shown in the figure. Figure 5 .

[0061] Example 2

[0062] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0063] (1) According to (Fe) 21 Co 34 Ni5Cr 13 Si 27 5Cu 95 The chemical formula for this alloy is as follows: using an SDPTOP-FA2004 electronic balance, the following raw materials were weighed: Fe: 0.933 g, Co: 1.595 g, Ni: 0.234 g, Cr: 0.538 g, Si: 0.604 g, Cu: 96.097 g.

[0064] (2) Melting and casting: Fe is first refined using vacuum arc melting. 21 Co 34 Ni5Cr 13 Si 27 Pre-alloying, then Fe 21 Co 34 Ni5Cr 13 Si 27 The pre-alloyed and high-purity copper are melted together and repeatedly melted 12 times, then vacuum-cast to obtain an ingot.

[0065] (3) Vacuum sealing of the ingot, filling it with 0.05MPa argon gas to provide a protective atmosphere at a pressure of 0.05MPa, and solidifying it in a box-type resistance furnace at 1000 ℃ for 1h, followed by water quenching to obtain the first billet;

[0066] (4) One-pass rolling: The first billet is subjected to multiple cold rolling passes with a total reduction of 40% to obtain the second billet;

[0067] (5) Recrystallization annealing: The second billet is vacuum sealed and filled with argon gas at 0.05 MPa, which provides a protective atmosphere at a pressure of 0.05 MPa. The billet is then recrystallized and annealed at 700 °C for 1 h to obtain the third billet.

[0068] (6) Secondary rolling: The third billet is subjected to multiple cold rolling passes with a total reduction of 50% to obtain the fourth billet;

[0069] (7) Aging: The fourth billet is vacuum sealed and filled with argon gas at 0.05 MPa, which provides a protective atmosphere at a pressure of 0.05 MPa. It is then aged at 450 °C for 24 h in a box-type resistance furnace to obtain FeCoNiCrSi system high-entropy particle-reinforced heat-resistant copper alloy.

[0070] The mechanical properties of the obtained high-entropy particle-reinforced heat-resistant copper alloy were tested, and the room temperature tensile stress-strain curves are shown below. Figure 6 .

[0071] The obtained high-entropy particle-reinforced heat-resistant copper alloy was characterized by SEM. The SEM characterization results are shown in the figure. Figure 7 ;Depend on Figure 7 It can be seen that the obtained high-entropy particle-reinforced heat-resistant copper alloy includes a copper matrix and a nano-precipitated phase (i.e., FeCoNiCrSi system high-entropy particle phase) dispersed in the copper matrix, and the precipitated phase is uniformly distributed in the copper matrix.

[0072] The obtained high-entropy particle-reinforced heat-resistant copper alloy was subjected to EDS energy dispersive spectroscopy, and the EDS characterization results are shown in the figure. Figure 8 .Depend on Figure 8 It can be seen that the nano-precipitated phase is composed of Fe, Co, Ni, Cr and Si, that is, the FeCoNiCrSi system high-entropy particle phase is generated in situ in the copper matrix.

[0073] The obtained high-entropy particle-reinforced heat-resistant copper alloy was characterized by HAADF testing, and the HAADF characterization results are shown below. Figure 9 .Depend on Figure 9 It can be seen that the high-entropy particle phase crystal and the copper matrix phase crystal of the FeCoNiCrSi system exhibit a coherent relationship.

[0074] The softening temperature of the obtained high-entropy particle-reinforced heat-resistant copper alloy was tested, and the resulting curve is shown in the figure. Figure 10 .

[0075] Example 3

[0076] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0077] (1) According to (Fe) 26 Co 41 Ni5Cr 16Si 12 )4Cu 96 The chemical formula for this alloy is as follows: using an SDPTOP-FA2004 electronic balance, the following raw materials were weighed: Fe: 0.920g, Co: 1.531g, Ni: 0.186g, Cr: 0.527g, Si: 0.214g, Cu: 96.623g.

[0078] (2) Melting and casting: Fe is first refined using vacuum arc melting. 26 Co 41 Ni5Cr 16 Si 12 Pre-alloying, then Fe 26 Co 41 Ni5Cr 16 Si 12 The pre-alloyed and high-purity copper are melted together and repeatedly melted 12 times, then vacuum-cast to obtain an ingot.

[0079] (3) Vacuum sealing of the ingot, filling it with 0.05MPa argon gas to provide a protective atmosphere at a pressure of 0.05MPa, and solidifying it in a box-type resistance furnace at 1000℃ for 1h, followed by water quenching to obtain the first billet.

[0080] (4) One-pass rolling: The first billet is subjected to multiple cold rolling passes with a total reduction of 40% to obtain the second billet;

[0081] (5) Recrystallization annealing: The second billet is vacuum sealed and filled with argon gas at 0.05 MPa, which provides a protective atmosphere at a pressure of 0.05 MPa. The billet is then recrystallized and annealed at 700 °C for 1 h to obtain the third billet.

[0082] (6) Secondary rolling: The third billet is subjected to multiple cold rolling passes with a total reduction of 50% to obtain the fourth billet;

[0083] (7) Aging: The fourth billet is vacuum sealed and filled with argon gas at 0.05 MPa, which provides a protective atmosphere at a pressure of 0.05 MPa. It is then aged at 450℃ for 24 hours in a box-type resistance furnace to obtain FeCoNiCrSi system high-entropy particle-reinforced heat-resistant copper alloy.

[0084] Example 4

[0085] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0086] (1) According to (Fe) 18 Co 28 Ni4Cr 10 Si 40 ) 5.5 Cu 94.5The chemical formula for this alloy is as follows: using an SDPTOP-FA2004 electronic balance, the following raw materials were weighed: Fe: 0.884g, Co: 1.451g, Ni: 0.206g, Cr: 0.457g, Si: 0.988g, Cu: 96.013g.

[0087] (2) Melting and casting: Fe is first refined using vacuum arc melting. 18 Co 28 Ni4Cr 10 Si 40 Pre-alloying, then Fe 18 Co 28 Ni4Cr 10 Si 40 The pre-alloyed and high-purity copper are melted together and repeatedly melted 12 times, then vacuum-cast to obtain an ingot.

[0088] (3) Vacuum sealing of the ingot, filling it with 0.05MPa argon gas to provide a protective atmosphere at a pressure of 0.05MPa, and solidifying it in a box-type resistance furnace at 1000℃ for 1h, followed by water quenching to obtain the first billet.

[0089] (4) One-pass rolling: The first billet is subjected to multiple cold rolling passes with a total reduction of 40% to obtain the second billet;

[0090] (5) Recrystallization annealing: The second billet is vacuum sealed and filled with argon gas at 0.05 MPa, which provides a protective atmosphere at a pressure of 0.05 MPa. The billet is then recrystallized and annealed at 700 °C for 1 h to obtain the third billet.

[0091] (6) Secondary rolling: The third billet is subjected to multiple cold rolling passes with a total reduction of 50% to obtain the fourth billet;

[0092] (7) Aging: The fourth billet is vacuum sealed and filled with argon gas at 0.05 MPa, which provides a protective atmosphere at a pressure of 0.05 MPa. It is then aged at 450℃ for 24 hours in a box-type resistance furnace to obtain FeCoNiCrSi system high-entropy particle-reinforced heat-resistant copper alloy.

[0093] Example 5

[0094] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0095] The only difference between this embodiment and embodiment 1 is that in step (3), the solution treatment temperature is changed to 800°C.

[0096] Example 6

[0097] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0098] The only difference between this embodiment and embodiment 1 is that in step (3), the solution treatment temperature is changed to 1200°C.

[0099] Example 7

[0100] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0101] The only difference between this embodiment and Embodiment 1 is that in step (5), the recrystallization annealing temperature is changed to 500°C.

[0102] Example 8

[0103] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0104] The only difference between this embodiment and Embodiment 1 is that in step (5), the recrystallization annealing temperature is changed to 900°C.

[0105] Example 9

[0106] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0107] The only difference between this embodiment and Embodiment 1 is that in step (5), the recrystallization annealing time is changed to 10 min.

[0108] Example 10

[0109] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0110] The only difference between this embodiment and Embodiment 1 is that in step (5), the recrystallization annealing time is changed to 4 hours.

[0111] Example 11

[0112] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0113] The only difference between this embodiment and embodiment 1 is that in step (7), the aging temperature is changed to 200°C.

[0114] Example 12

[0115] A method for preparing a high-entropy particle-reinforced heat-resistant copper alloy:

[0116] The only difference between this embodiment and embodiment 1 is that in step (7), the aging temperature is changed to 600°C.

[0117] Comparative Example 1

[0118] A method for preparing a copper alloy:

[0119] The only difference between this comparative example and Example 1 is that steps (6) and (7) were not performed, that is, high-entropy particles were not formed in situ in the copper matrix, and FeCoNiCrSi copper alloy was obtained directly.

[0120] Test methods

[0121] Mechanical Properties: The room temperature mechanical properties of the alloys were tested using a CMT4105 universal electronic tensile testing machine. Each sample was machined into a dog-bone shaped tensile specimen using a wire cutter. Subsequently, the oxide scale and defects on the surface and sides of the specimens were removed sequentially using 240-grit, 600-grit, and 1000-grit sandpaper until smooth. The mechanical properties of the specimens were measured using an extensometer with a gauge length of 15 mm. The yield strength, tensile strength, and tensile strain of each sample at room temperature (25±2℃) were obtained.

[0122] Conductivity: The resistance of each sample was measured using a precision Applent AT512 resistor at room temperature using a two-arm bridge method, and the conductivity was calculated.

[0123] Softening temperature: After vacuum sealing each sample, annealing was performed at 500℃, 550℃, 600℃, 650℃, and 700℃ for 1 hour. The micro Vickers hardness tester used was a 430SVD, with a test load of 200 g and a pressing time of 15 s. To minimize the impact of errors on the experiment, 10 test data were randomly selected for each sample. The maximum and minimum values ​​were then removed, and the average of the remaining 8 values ​​was calculated to obtain the final hardness value. The annealing temperature at which the final hardness decreased by 20% corresponds to the softening temperature.

[0124] Electron microscopy testing: Each sample was electropolished and characterized using SEM to obtain the particle size of the nano-precipitates in each sample. EDS was also used in conjunction with SEM. Transmission electron microscopy (TEM) was used to prepare transmission samples using focused ion beam (FIB) and to characterize the nano-precipitates in each sample, obtaining their lattice constants and lattice mismatch with the copper matrix.

[0125] The copper alloy samples obtained in each embodiment and comparative example were subjected to the above tests, and the results are shown in Table 1 and Table 2.

[0126] Table 1

[0127]

[0128] Table 2

[0129]

[0130] As can be seen from the above description, compared with the various comparative examples, the above embodiments of the present invention, through precise design of the elemental composition of the alloy, and the in-situ formation of FeCoNiCrSi-based high-entropy particles, a nanoscale coherent precipitate phase, in the copper matrix, significantly improves the mechanical strength of the obtained high-entropy particle-reinforced heat-resistant copper alloy and also promotes its superior heat resistance.

[0131] Specifically, in each embodiment:

[0132] Comparing Examples 3 and 4 with Examples 1 and 2, it can be seen that (Fe) 23 Co 35 Ni5Cr 14 Si 23 ) 4.5 Cu 95.5 and (Fe) 21 Co 34 Ni5Cr 13 Si 27 5Cu 95 In these two types of copper alloys, the FeCoNiCrSi system high-entropy particle phase can achieve a more precise coherent match with the copper matrix, thereby significantly optimizing the crystal structure and metallographic structure of the resulting copper alloy, ultimately yielding a high-entropy particle-reinforced heat-resistant copper alloy with both higher mechanical properties and higher heat resistance.

[0133] Comparing Examples 5 and 6 with Example 1, it can be seen that by optimizing the solution treatment temperature, the high-entropy particle components in the precursor alloy can be effectively dissolved and stabilized, allowing them to fully integrate into the copper matrix and form a solid solution. This lays the groundwork for the effective formation of subsequent precipitates, ultimately resulting in a copper alloy with higher overall performance.

[0134] Comparing Examples 7 and 8 with Example 1, it can be seen that by optimizing the recrystallization annealing temperature, recrystallization inside the alloy can be promoted more effectively, the crystal structure damaged by cold rolling can be restored, and ultimately higher mechanical properties and heat resistance can be exhibited.

[0135] Comparing Examples 9 and 10 with Example 1, it can be seen that by optimizing the recrystallization annealing time, the crystal structure can be restored more effectively, promoting the more ordered growth of FeCoNiCrSi system high-entropy particles as in-situ precipitates, further refining the grain structure of the alloy, and thus significantly improving the toughness and high strength of the final copper alloy.

[0136] Comparing Examples 11 and 12 with Example 1, it can be seen that by optimizing the aging treatment temperature, high-entropy particles can be induced to form a uniformly distributed nanoscale coherent precipitate phase in the copper matrix, which ultimately significantly improves the mechanical strength of the obtained high-entropy particle-reinforced heat-resistant copper alloy.

[0137] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those described herein.

[0138] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-entropy particle-reinforced heat-resistant copper alloy, characterized by, The high-entropy particle reinforced heat-resistant copper alloy comprises a copper matrix phase and FeCoNiCrSi high-entropy particle phases dispersed in the copper matrix phase; and the chemical formula of the high-entropy particle reinforced heat-resistant copper alloy is (Fe a Co b Ni c Cr d Si e ) x Cu 100-x , wherein a is 15-30, b is 25-45, c is 1-5, d is 10-20, e is 10-40, and x is 4-6. The lattice constant of the FeCoNiCrSi high-entropy particle phase is 0.351 nm to 0.357 nm. The lattice mismatch degree between the FeCoNiCrSi high-entropy particle phase and the copper matrix phase is 0.05% to 0.3%. The tensile strength of the high-entropy particle reinforced heat-resistant copper alloy is 400 MPa to 550 MPa. The softening temperature of the high-entropy particle reinforced heat-resistant copper alloy is 550°C to 600°C.

2. The high-entropy particle-reinforced heat-resistant copper alloy of claim 1, wherein, The FeCoNiCrSi high-entropy particle phase and the copper matrix phase are in a coherent relationship, and the particle size of the FeCoNiCrSi high-entropy particle phase is 5 nm to 50 nm.

3. The high-entropy particle-reinforced heat-resistant copper alloy of claim 2, wherein, In the chemical formula of the high-entropy particle reinforced heat-resistant copper alloy, a is 18 to 26, b is 28 to 41, c is 4 to 5, d is 10 to 16, e is 12 to 40, and x is 4 to 5.

5.

4. The high-entropy particle reinforced heat-resistant copper alloy according to any one of claims 1 to 3, characterized in that, The yield strength of the high-entropy particle reinforced heat-resistant copper alloy is 400 MPa to 500 MPa; and / or, The tensile strain of the high-entropy particle reinforced heat-resistant copper alloy is 10% to 20%; and / or, The electrical conductivity of the high-entropy particle reinforced heat-resistant copper alloy is 60% IACS to 75% IACS.

5. A method of producing the high-entropy particle-reinforced heat-resistant copper alloy according to any one of claims 1 to 4, characterized by, Comprising: Step S1, preparing raw materials according to the chemical formula of the high-entropy particle reinforced heat-resistant copper alloy; Step S2, using a vacuum arc melting method to prepare a precursor alloy of the FeCoNiCrSi high-entropy particle phase; the precursor alloy and copper raw materials are sequentially subjected to melting and vacuum suction casting to obtain an ingot; Step S3, performing solid solution treatment on the ingot at a temperature of 1000±100°C under a protective atmosphere with a pressure of 0.05±0.001 MPa to obtain a first blank; Step S4, cold rolling the first blank to obtain a second blank; Step S5, performing annealing treatment on the second blank at a temperature of 600°C to 800°C under a protective atmosphere with a pressure of 0.05±0.001 MPa to obtain a third blank; Step S6, cold rolling the third blank to obtain a fourth blank; Step S7, performing aging treatment on the fourth blank at a temperature of 250°C to 550°C under a protective atmosphere with a pressure of 0.05±0.001 MPa to cause the FeCoNiCrSi high-entropy particle phase to precipitate in situ to obtain the high-entropy particle reinforced heat-resistant copper alloy.

6. The method of claim 5, wherein the high-entropy particle-reinforced heat- resistant copper alloy is prepared by the steps of: preparing a high-entropy copper alloy by mixing copper and at least one of aluminum, cobalt, nickel, and chromium; and adding a plurality of particles to the high-entropy copper alloy. In the step S3, the solid solution treatment time is 1 h to 4 h.

7. The method of claim 5 or 6, wherein the high-entropy particle-reinforced heat- resistant copper alloy is prepared by the steps of: preparing a copper alloy powder by a powder metallurgy method; and mixing the copper alloy powder with a high-entropy alloy powder to prepare a mixed powder, and then sintering the mixed powder. In the step S5, the annealing treatment time is 0.5 h to 3 h.

8. The method of claim 5 or 6, wherein the high-entropy particle-reinforced heat- resistant copper alloy is prepared by the steps of: preparing a copper alloy powder by a powder metallurgy method; and mixing the copper alloy powder with a high-entropy alloy powder to prepare a mixed powder, and then sintering the mixed powder. In the step S7, the aging treatment time is 1 h to 24 h.

9. The preparation method of the high-entropy particle reinforced heat-resistant copper alloy according to claim 5 or 6, characterized in that, In the step S3, the step S5, and the step S7, the protective atmosphere is argon; and / or, The down pressure of the first cold rolling and the second cold rolling is independently 30% to 60%.

10. Use of the high-entropy particle-reinforced heat-resistant copper alloy of any one of claims 1 to 4 as an alloy material in the aerospace field, the transportation field, or the industrial manufacturing field.

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