A kind of kagome metal composite material with ultra-wide temperature range and low expansion, and its preparation and application

Abstract

The present invention belongs to the field of new material technologies, and particularly relates to a kagome metal composite material with ultra-wide temperature range and low expansion, as well as its preparation and application. In this preparation method, a Co phase is introduced into the Re-Fe binary kagome metal, effectively broadening its low-expansion temperature range. Then, α-Fe is introduced to construct a dual-phase structure of Re-Fe-Co matrix and α-(Fe / Co), where Re-Fe-Co exhibits negative thermal expansion and α-(Fe,Co) exhibits positive thermal expansion. By controlling the Fe content to regulate the proportion of the two phases, the thermal expansion behavior is regulated to obtain a kagome metal composite material with ultra-wide temperature range and low expansion. The kagome metal composite material with ultra-wide temperature range and low expansion prepared by the present invention constructs a soft / hard heterogeneous structure. The synthesis steps are simple and easy to implement, and the significant improvements in both ultra-wide temperature range and low expansion performance and mechanical strength are achieved respectively through a two-step method.

Description

Technical Field

[0001] The present invention belongs to the technical field of new materials, and particularly relates to a kagome metal composite material with ultra-wide temperature range and low expansion, as well as its preparation and application. Background Art

[0002] In fields such as high-temperature precision instruments and aerospace, the dimensional stability of components is directly related to the performance and lifespan of equipment. Therefore, there is an urgent need to develop low-expansion materials that can maintain their dimensions unchanged in extreme high-temperature environments. However, the existing types of low-expansion materials are limited, especially those that can maintain low-expansion characteristics in high-temperature environments are scarce.

[0003] Although ceramic materials have certain high-temperature resistance, their insufficient mechanical properties and limitations in thermal and electrical conductivity make it difficult for them to meet the requirements of high-temperature precision applications. Although metal materials perform excellently in terms of heat conduction and electricity conduction, intermetallic compounds with high-temperature low-expansion properties have inherent brittleness, and their low-expansion temperature range is often relatively low, making it difficult to be applied in high-temperature environments.

[0004] To solve the above problems, the design of composite materials is an effective strategy. Traditional composite materials are prepared by solid-phase sintering. However, this method often leads to limited improvement in mechanical properties, and the mismatch of the thermal expansion coefficients of the two materials is likely to cause thermal cracks, thereby resulting in material failure. Therefore, how to scientifically design and prepare composite materials that can maintain low-expansion characteristics in high-temperature environments and at the same time have excellent mechanical properties is a research hotspot and difficulty in the current field of materials science. Summary of the Invention

[0005] The present invention discloses a kagome metal composite material with ultra-wide temperature range and low expansion, as well as its preparation and application, so as to solve any one of the above and other potential problems in the prior art.

[0006] To solve the above technical problems, the technical solution of the present invention is: a kagome metal composite material with ultra-wide temperature range and low expansion, and the chemical formula of the kagome metal composite material with ultra-wide temperature range and low expansion is R2Fe 11 Co6Fe x , where 0 < x ≤ 50, R is a rare earth element, and the kagome metal composite material with ultra-wide temperature range and low expansion has an R-Fe-Co phase and an α-(Fe,Co) phase.

[0007] Furthermore, the R-Fe-Co phase is a hard matrix phase, showing strong magnetism and a Curie temperature as high as 800K, and the α-(Fe,Co) phase is a plastic second phase, which improves the strength of the matrix phase through chemical compounding.

[0008] Furthermore, the R-Fe-Co phase is hexagonal crystal system with the space group of P63 / mmc; the α-(Fe,Co) phase is cubic crystal system with the space group of Im-3m.

[0009] Furthermore, the chemical formula of the ultra-wide temperature range low-expansion kagome metal composite is Lu2Fe 11 Co6Fe9, and the Lu2Fe 11 Co6Fe9 exhibits low-expansion characteristics in the temperature range of 110~800K, and the linear expansion coefficient α l is 0.98×10 -6 , and the compressive strength reaches 1110 Mpa.

[0010] Furthermore, the chemical formula of the ultra-wide temperature range low-expansion kagome metal composite is Y2Fe 11 Co6Fe9, and the Y2Fe 11 Co6Fe9 exhibits low-expansion characteristics in the temperature range of 110~800K, and the thermal expansion coefficient α l <3×10 -6 , and the compressive strength <1110 Mpa.

[0011] Furthermore, the chemical formula of the ultra-wide temperature range low-expansion kagome metal composite is Tb2Fe 11 Co6Fe9, and the Tb2Fe 11 Co6Fe9 exhibits low-expansion characteristics in the temperature range of 110~800K, and the thermal expansion coefficient α l is less than 3×10 -6 , and the compressive strength <1110 Mpa.

[0012] The chemical formula of the ultra-wide temperature range low-expansion kagome metal composite is Lu2Fe 11 Co6Fe 15 , and the Lu2Fe 11 Co6Fe 15 has strong anisotropic characteristics.

[0013] Another object of the present invention is to provide a method for preparing the above-mentioned ultra-wide temperature range low-expansion kagome metal composite, and the method specifically includes the following steps:

[0014] S1) Prepare corresponding raw materials according to the R-Fe-Co ternary kagome metal and the α-(Fe,Co) phase;

[0015] S2) Mix the raw materials prepared in S1);

[0016] S3) Melting and homogenizing the raw materials mixed in S2) through an arc furnace;

[0017] S4) Annealing the homogenized sample under a protective atmosphere;

[0018] S5) After the annealing is completed, a super-wide temperature range low-expansion kagome metal composite material is obtained.

[0019] The super-wide temperature range low-expansion kagome metal composite material exhibits low-expansion characteristics in the temperature range of 110 - 800K, and the thermal expansion coefficient α l <3×10 -6 , and the compressive strength ≤ 1110 Mpa

[0020] Furthermore, in the S1), the purities of both the R-Fe-Co ternary kagome metal raw material and the α-Fe raw material are > 99.9%.

[0021] Furthermore, the specific annealing process in the S4) is: annealing at a temperature of 1100 °C for at least 72 h; the protective atmosphere is an inert gas.

[0022] An above-mentioned super-wide temperature range low-expansion kagome metal composite material is applied in the fields of optical instruments, microelectronic devices, and high-precision instruments in aerospace.

[0023] The technical effect of the present invention: Due to the adoption of the above technical solution, the present invention provides a super-wide temperature range low-expansion kagome metal composite material and its preparation method. First, an appropriate amount of Co is introduced into the R-Fe binary kagome metal (R refers to rare earth elements) to prepare an R-Fe-Co ternary precursor compound. Subsequently, α-Fe is introduced to form an R-Fe-Co ternary kagome metal composite material, constructing a soft / hard heterogeneous structure. The synthesis steps are simple and easy to implement, and the significant improvement of the super-wide temperature range low-expansion performance and mechanical strength is realized through a two-step method.

[0024] On the one hand, the present invention provides a preparation method of a super-wide temperature range low-expansion kagome metal composite material. The preparation method introduces a Co phase into the R-Fe binary kagome metal, effectively broadening its low-expansion temperature range. Then, α-Fe is introduced to construct a two-phase structure of an R-Fe-Co matrix and α-(Fe / Co), where R-Fe-Co exhibits negative thermal expansion and α-(Fe,Co) exhibits positive thermal expansion. The thermal expansion behavior is regulated by controlling the Fe content to adjust the ratio of the two phases, and a super-wide temperature range low-expansion kagome metal composite material is obtained.

[0025] The super-wide temperature range low-expansion kagome metal composite material prepared by the present invention has excellent dimensional stability, high precision, and long service life. Its remarkable feature is that the shape and size are not affected by temperature changes, achieving a constant length / volume in a specific temperature range, that is, zero thermal expansion characteristics.

[0026] The ultra-wide temperature range low-expansion kagome metal composite material provided by the present invention has the characteristics of high strength in the high-temperature range, and its shape and size remain stable when the temperature changes. Compared with intermetallic compounds, the working temperature range of this material is broadened and its intrinsic brittleness is eliminated. At the same time, compared with ceramic materials, this material exhibits better thermal and electrical conductivity, and the raw material cost is lower, which makes practical applications possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 is the X-ray diffraction structure refinement pattern of Lu2Fe 11 Co6Fe9 biphasic powder at 300 K;

[0029] Figure 2 is the crystal structure diagram of the R-Fe-Co phase and the α-(Fe,Co) phase of the present invention;

[0030] Figure 3 is the backscattered electron diffraction microstructural diagram of the R-Fe-Co phase and the α-(Fe,Co) phase of the present invention;

[0031] Figure 4 is R2Fe of the present invention 11 Co6Fe x (R = Lu, x = 9, 15, 25 and 50) and the linear expansion diagram of the α-Fe phase;

[0032] Figure 5 is the engineering stress-strain curve of Lu2Fe 11 Co6Fe9 at 300 K and the sample diagram of processing and forming. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] In order to better understand the technical solutions of the present invention, the embodiments of the present invention will be described in detail below with reference to the drawings.

[0034] It should be clear that the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0035] The terms used in the embodiments of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The singular forms "a", "the", and "said" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms unless the context clearly dictates otherwise.

[0036] The present invention provides an ultra-wide temperature range low-expansion kagome metal composite material, and the chemical formula of the ultra-wide temperature range low-expansion kagome metal composite material is R2Fe 11 Co6Fe x , where 0 < X ≤ 50, R is a rare earth element, and the ultra-wide temperature range low-expansion kagome metal composite material includes Lu2Fe 11 Co6Fe9, and the Lu2Fe 11 Co6Fe9 exhibits low-expansion characteristics in the temperature range of 110 - 800K, and the linear expansion coefficient α l is 0.98×10 -6 .

[0037] The preparation method introduces a Co phase into the R-Fe binary kagome metal, effectively broadening its low-expansion temperature range. Then, α-Fe is introduced to construct a dual-phase structure of R-Fe-Co matrix and α-(Fe / Co), where R-Fe-Co exhibits negative thermal expansion and α-(Fe,Co) exhibits positive thermal expansion. By controlling the Fe content to regulate the proportion of the two phases, the thermal expansion behavior is regulated to obtain an ultra-wide temperature range low-expansion kagome metal composite material.

[0038] The preparation method includes the following steps:

[0039] S1): Prepare the corresponding raw materials according to the R-Fe-Co and α-(Fe,Co) phases, and the purity of the raw materials is >99.9%. The R-Fe-Co phase is a hexagonal crystal system with a space group of P63 / mmc, and the α-(Fe,Co) phase is a cubic crystal system with a space group of Im-3m.

[0040] S2): Mix the raw materials prepared in S1).

[0041] S3): Melt the mixed raw materials evenly through an arc furnace.

[0042] S4): Place the sample obtained by uniform melting under a protective atmosphere and anneal it at 1100°C for at least 72h.

[0043] S5): After the annealing is completed, an ultra-wide temperature range low-expansion kagome metal composite material is obtained.

[0044] The protective atmosphere is an inert atmosphere.

[0045] Example 1:

[0046] To prepare the component of the present invention, Lu2Fe 11 The bulk of the Lu2FeCo6Fe9 ultra-wide temperature range low-expansion kagome metal composite material is synthesized by an electric arc furnace melting method respectively:

[0047] The specific operation is carried out according to the following steps:

[0048] Weigh 8 g of Lu, Fe, and Co raw materials with a molar ratio of 2:20:6 respectively. Mix the raw materials in an electric arc furnace, evacuate the furnace body (vacuum degree < 2×10 -3 Pa), and then repeatedly melt 4 times under the protection of inert gas Ar, 2 minutes each time. Place the obtained sample in an inert atmosphere, anneal at a temperature of 1100 °C for 72 h. The X-ray diffraction results show that the obtained product is a composite phase of Lu2(Fe,Co) 17 and α-(Fe,Co), without other impurities.

[0049] Example 2:

[0050] To prepare the component of the present invention, Y2Fe 11 The bulk of the Y2FeCo6Fe9 ultra-wide temperature range low-expansion kagome metal composite material is synthesized by an electric arc furnace melting method respectively:

[0051] The specific operation is carried out according to the following steps:

[0052] Weigh 8 g of Y, Fe, and Co raw materials with a molar ratio of 2:20:6 respectively. Mix the raw materials in an electric arc furnace, evacuate the furnace body

[0053] (vacuum degree < 2×10 -3 Pa), and then repeatedly melt 4 times under the protection of inert gas Ar, 2 minutes each time. Place the obtained sample in an inert atmosphere, anneal at a temperature of 1100 °C for 75 h. The X-ray diffraction results show that the obtained product is a composite phase of Y2(Fe,Co) 17 and α-(Fe,Co), without other impurities.

[0054] Example 3:

[0055] To prepare the component of the present invention, Tb2Fe 11 The bulk of the Tb2FeCo6Fe9 ultra-wide temperature range low-expansion kagome metal composite material is synthesized by an electric arc furnace melting method respectively:

[0056] The specific operation is carried out according to the following steps:

[0057] Weigh 8 g of Tb, Fe, and Co raw materials with a molar ratio of 2:20:6 respectively. Mix the raw materials in an electric arc furnace, evacuate the furnace body (vacuum degree < 2×10 -3Pa), and then repeatedly melted 4 times under the protection of inert gas Ar, 2 minutes each time. The obtained sample was annealed at 1100 °C for 80 h in an inert atmosphere. X-ray diffraction results showed that the obtained product was a composite phase of Tb2(Fe,Co) 17 and α-(Fe,Co), without other impurities.

[0058] For the ultra-wide temperature range low-expansion kagome metal composites Lu2Fe 11 Co6Fe9, Y2Fe 11 Co6Fe9, Tb2Fe 11 Co6Fe9 obtained in Examples 1, 2, and 3, the linear expansion was measured, and they showed low-expansion characteristics in the temperature ranges of 110 - 800 K, 110 - 800 K, and 110 - 800 K respectively. The thermal expansion coefficient (α l ) was less than 3×10 -6 .

[0059] In the preparation method of the present invention, the R-Fe-Co ternary kagome metal is a hard matrix phase, and the α-(Fe,Co) phase is a plastic second phase. Through the two-step method, the low-expansion temperature range can be widened step by step and the mechanical behavior of the matrix phase can be improved, realizing high-strength and low-expansion performance in the high-temperature domain.

[0060] Figure 1 This is the ultra-wide temperature range low-expansion kagome metal composite material of the present invention. When R = Lu, the X-ray diffraction structure refinement pattern of Lu2Fe 11 Co6Fe9 powder at 300 K. It can be seen from this figure that the X-ray diffraction pattern simulated based on its crystal structure is consistent with the experimentally obtained X-ray diffraction pattern, indicating the correctness of the structure model of the ultra-wide temperature range low-expansion kagome metal composite material of the present invention.

[0061] Figure 2 This is the crystal structure diagram of the R-Fe-Co phase and the α-(Fe,Co) phase of the present invention. The crystal structures of the present invention are respectively a rare earth-rich 2:17 type hexagonal phase and a cubic phase composed of Fe and a small amount of Co elements.

[0062] Figure 3 This is the backscattered electron diffraction microstructural diagram of the R-Fe-Co phase and the α-(Fe,Co) phase of the present invention. It can be seen that the R-Fe-Co phase is the substrate phase, the α-(Fe,Co) phase is the precipitated phase, and the two phases are uniformly mixed without compositional segregation.

[0063] Figure 4 This is the linear expansion diagram of R2Fe11Co6Fex (R = Lu, x = 9, 15, 25 and 50) of the present invention. From the Lu2Fe described in the present invention 11Co6Fe x From the linear thermal expansion curve, it can be seen that by regulating the doping ratio of Fe, thermal expansion can be controlled, and zero expansion characteristics are exhibited in the Lu2Fe11Co6Fe9 component, with a thermal expansion coefficient of 0.98×10 -6 .

[0064] Figure 5 is the engineering stress-strain curve of Lu2Fe 11 Co6Fe9 at 300K. From the engineering stress-strain curve described in the present invention, it can be seen that the above low-expansion composite material exhibits excellent mechanical properties, with a compressive strength reaching 1110 Mpa and being processable.

[0065] The above provides a detailed introduction to a low-expansion kagome metal composite material with an ultra-wide temperature range, its preparation, and application provided by the embodiments of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

[0066] As used in the specification and claims, certain terms are used to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. The specification and claims do not use the difference in names as a way to distinguish components, but use the difference in functions of components as the criterion for distinction. As mentioned throughout the specification and claims, "comprising" and "including" are open-ended terms, so they should be interpreted as "including / including but not limited to". "Roughly" means within an acceptable error range, and those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect. The subsequent description of the specification is for the purpose of describing the preferred embodiments of implementing the present application, but the description is for the purpose of explaining the general principles of the present application and is not intended to limit the scope of the present application. The protection scope of the present application shall be subject to what is defined by the appended claims.

[0067] It should also be noted that the term "including", "comprising", or any other variant thereof is intended to cover non-exclusive inclusion, so that a commodity or system including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such a commodity or system. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the commodity or system including the said element.

[0068] It should be understood that the term "and / or" used herein is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: the existence of A alone, the simultaneous existence of A and B, and the existence of B alone. Additionally, the character " / " in this text generally indicates that the associated objects before and after are in an "or" relationship.

[0069] The above description shows and describes several preferred embodiments of the present application. However, as previously mentioned, it should be understood that the present application is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications, and environments, and can be altered within the scope of the application concept described herein through the above teachings or the technology or knowledge in the relevant field. Any alterations and changes made by those skilled in the art that do not depart from the spirit and scope of the present application shall fall within the protection scope of the appended claims of the present application.

Claims

1. A cage - like metal composite material with ultra - wide temperature range and low expansion, characterized in that, The chemical formula of the ultra-wide temperature range low-expansion kagome metal composite is R2Fe 11 Co6Fe x , where 0 < x ≤ 50, R is a rare earth element, and the ultra-wide temperature range low-expansion kagome metal composite has an R-Fe-Co phase and an α-(Fe,Co) phase; The R-Fe-Co phase is a hard matrix phase, showing strong magnetism and having a Curie temperature as high as 800 K. The α-(Fe,Co) phase is a plastic precipitation phase, which improves the mechanical properties of the matrix phase through chemical compounding. The R-Fe-Co phase is of hexagonal crystal system with the space group of P63 / mmc; the α-(Fe,Co) phase is of cubic crystal system with the space group of Im-3m.

2. The ultra-wide temperature range low-expansion kagome metal composite material according to claim 1, wherein The chemical formula of the ultra-wide temperature range low-expansion kagome metal composite material is Lu2Fe 11 Co6Fe9, and the Lu2Fe 11 Co6Fe9 exhibits zero-expansion characteristics in the temperature range of 110~800K, and the linear expansion coefficient α l is 0.98×10 -6 , and the compressive strength is 1110 MPa.

3. The ultra-wide temperature range low-expansion kagome metal composite material according to claim 1, wherein The chemical formula of the ultra-wide temperature range low-expansion kagome metal composite material is Y2Fe 11 Co6Fe9, and the Y2Fe 11 Co6Fe9 exhibits low-expansion characteristics in the temperature range of 110~800K, and the linear expansion coefficient α l <3×10 -6 , and the compressive strength < 1110 MPa.

4. The ultra-wide temperature range low-expansion kagome metal composite material according to claim 1, wherein The chemical formula of the ultra-wide temperature range low-expansion kagome metal composite material is Tb2Fe 11 Co6Fe9 measures the linear expansion. The Tb2Fe 11 Co6Fe9 exhibits low-expansion characteristics in the temperature range of 110~800K, and the linear expansion coefficient α l <3×10 -6 , and the compressive strength < 1110 MPa.

5. A method for preparing the ultra-wide temperature range low-expansion kagome metal composite material according to any one of claims 1-4, characterized in that, The method specifically includes the following steps: S1) Prepare corresponding raw materials according to the R-Fe-Co phase and α-(Fe,Co) phase of the ultra-wide temperature range low-expansion kagome metal composite material; S2) Mix the raw materials prepared in S1); S3) Uniformly melt the raw materials mixed in S2) through an electric arc furnace; S4) Anneal the uniformly melted sample under a protective atmosphere; S5) After the annealing is completed, an ultra-wide temperature range low-expansion kagome metal composite material is obtained.

6. The method according to claim 5, characterized in that, The specific annealing process in S4) is: annealing at a temperature of 1100 °C for at least 72 h; the protective atmosphere is an inert gas.

7. An ultra-wide temperature range low-expansion kagome metal composite material as described in any one of claims 1-4 is applied in the fields of optical instruments, microelectronic devices, and high-precision instruments in aerospace.

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