Layered / rod eutectic high-entropy alloy and design method and preparation method thereof

Abstract

The application belongs to the technical field of metal materials and its preparation, and discloses a layer / rod eutectic high-entropy alloy and a design method and a preparation method thereof. The preparation method is as follows: obtaining alloy components and eutectic structure forms of a eutectic alloy system, establishing a database; screening a candidate set of the eutectic alloy system with lamellar eutectic and / or rod eutectic, obtaining eutectic point components and determining key alloy elements; determining a candidate set of doped alloy elements to partially replace the key alloy elements, forming a eutectic high-entropy alloy system according to a predefined atomic molar ratio content, and screening to obtain a layer / rod eutectic high-entropy alloy meeting the requirements of 6.5<VEC<8.38, -18<ΔHmix<‑6 and a melting point difference of ≤35℃. The design method of the application is simple to operate, does not need complex calculation or formula deduction, and does not need secondary design, and can quickly determine the interval of the alloy system forming eutectic, and is high in efficiency and success probability.

Description

Technical Field

[0001] This invention relates to the field of metallic materials and their preparation technology, and in particular to a layer / rod eutectic high-entropy alloy and its design and preparation methods. Background Technology

[0002] Eutectic high-entropy alloys are a new type of alloy with great advantages. They combine the advantages of high-entropy alloys and eutectic alloys, have high phase stability, overcome the compositional segregation phenomenon of high-entropy alloys, and have good fluidity and castability. They also reconcile the contradiction between the strength and plasticity of metallic materials, greatly improving the application prospects of high-entropy alloys. Therefore, they have attracted strong attention from many researchers at home and abroad.

[0003] However, due to the multi-principal element characteristics of high-entropy alloys, it is difficult to accurately obtain a complete eutectic structure when designing and preparing eutectic high-entropy alloys. Although there are design methods for eutectic high-entropy alloys, such as the mixing enthalpy method, simple mixing method, infinite solid solution method, and machine learning method, these methods either require determining the composition of existing eutectic high-entropy alloys and performing secondary design based on this, or require simulation calculations through thermodynamic databases. This makes it difficult to quickly determine the range in which a eutectic can form for an alloy system with any selected composition. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a layer / rod eutectic high-entropy alloy, its design method, and its preparation method.

[0005] The present invention provides a layered / rod-shaped eutectic high-entropy alloy, its design method, and its preparation method, which are achieved through the following technical solutions:

[0006] This invention provides a design method for layered / rod-shaped eutectic high-entropy alloys, comprising the following steps:

[0007] Step 1, Create a database:

[0008] The alloy composition and eutectic microstructure of eutectic alloy systems were obtained from publicly available literature data. A database was established using the corresponding data of eutectic microstructure as input data and the alloy composition of eutectic alloy systems as output data.

[0009] It should be noted that this invention considers that structure determines performance, and different microstructures have a significant impact on the properties of alloys. Generally speaking, eutectic alloys exhibit three regular microstructures: spheroidal eutectic, rod-shaped eutectic, and lamellar eutectic. Among them, spheroidal eutectic structures typically possess high toughness and impact resistance, but lower strength and stiffness; lamellar eutectic structures typically possess high thermal stability and corrosion resistance, but lower strength and stiffness; rod-shaped eutectic structures typically possess high strength and toughness. Rod-shaped eutectic structures are equivalent to reinforcing phases distributed in a fibrous manner on the metal solid solution matrix, and under load, the fibrous reinforcing phase plays a major role. Therefore, under the same composition and grain size, rod-shaped structures possess good plasticity, toughness, and fatigue resistance. Based on the above, this invention attempts to design alloy compositions with lamellar and / or rod-shaped eutectic microstructures to simultaneously improve the strength and plasticity of high-entropy alloys, thereby obtaining high-strength and high-toughness eutectic high-entropy alloys.

[0010] To facilitate the selection of eutectic alloy systems with lamellar and / or rod-shaped eutectic structures based on the eutectic microstructure, this invention first establishes a database based on publicly available literature data on the alloy composition and eutectic microstructure of eutectic alloy systems. Specifically, the database uses the corresponding data on the eutectic microstructure as input data and the corresponding alloy composition of the eutectic alloy system as output data.

[0011] The alloy composition includes a eutectic point composition, which includes the types of alloying elements at the eutectic point and the corresponding content of each alloying element.

[0012] Step 2, determine the candidate set of basic alloying elements:

[0013] Using lamellar eutectic and / or rod-shaped eutectic as constraints, the database is screened to obtain a candidate set of eutectic alloy systems with lamellar eutectic and / or rod-shaped eutectic; the eutectic point composition of each eutectic alloy system in the candidate set is obtained as a candidate set of basic alloying elements.

[0014] It should be noted that the present invention uses the eutectic microstructure as input and lamellar and / or rod-shaped eutectic microstructure as constraints to filter the database, thereby obtaining eutectic alloy system data with the desired eutectic microstructure. The obtained eutectic alloy system data with the desired eutectic microstructure includes the types of alloying elements in the eutectic point composition and the corresponding content of each alloying element.

[0015] This invention obtains the eutectic point composition of each eutectic alloy system in the candidate set of the eutectic alloy system, that is, the alloy composition that can form lamellar eutectic and / or rod-shaped eutectic. The alloy composition is used as the basic alloy element candidate set to ensure that the obtained alloy composition can achieve the formation of lamellar eutectic and / or rod-shaped eutectic.

[0016] Step 3, Identify key alloying elements:

[0017] Obtain the types and contents of alloying elements in the eutectic point composition of the candidate basic alloying elements, sort the types of alloying elements in the eutectic point composition in order of their contents, and take the alloying element with the highest content as the key alloying element.

[0018] It should be noted that the present invention first identifies key alloying elements so that subsequent alloying can be improved by introducing doping alloying elements that can alloy with the key alloying elements.

[0019] This invention takes into account the influence of multi-principal element composition on the microstructure and mechanical properties of high-entropy alloys, and uses the alloying element with the highest content in the eutectic point composition as the key alloying element to achieve the effect of refining the eutectic microstructure and enhancing the overall strength and plasticity.

[0020] Step 4, determine the candidate set of doping alloying elements:

[0021] Using the types of alloying elements that can be infinitely solidified with the key alloying element and / or have a tendency to eutectic as constraints, the database is screened to obtain a candidate set of doped alloying elements.

[0022] It should be noted that, in order to ensure that the added doped alloying elements can improve the strength and plasticity of the key alloying elements after introduction, the present invention uses alloying elements that can be infinitely dissolved or exist in a eutectic state with the key alloying elements as constraints.

[0023] In some preferred embodiments of the present invention, alloy elements in the database are screened to meet the constraints of having similar atomic radii and crystal structures to the key alloy element, and having only a single-phase region below the liquidus line in the binary phase diagram formed with the key alloy element. The alloy elements obtained from the screening are those that can be infinitely dissolved in the key alloy element.

[0024] In some preferred embodiments of the present invention, the alloy elements in the database are screened to meet the constraint that the valence electron concentration VEC≥8 of the alloy formed with the key alloy element. The alloy elements obtained by screening are the alloy elements that have a eutectic tendency with the key alloy element.

[0025] Step 5, establishing a candidate set of lamellar / rod eutectic high-entropy alloys:

[0026] Using several doped alloy elements selected from the candidate set of doped alloy elements as doping sources, partially replace the key alloy elements in the candidate set of base alloy elements, and form a eutectic high-entropy alloy system composed of at least five alloy elements according to the predefined atomic molar ratio content, thereby establishing a candidate set of lamellar / rod eutectic high-entropy alloys.

[0027] It should be noted that when partially replacing the key alloy elements in the candidate set of base alloy elements, the number of selected doped alloy elements is related to the actually determined base alloy elements. When the eutectic point composition selected from the candidate set of base alloy elements is a ternary system alloy, at least 2 doped alloy elements are selected from the candidate set of doped alloy elements. When the eutectic point composition selected from the candidate set of base alloy elements is a binary system alloy, at least 3 doped alloy elements are selected from the candidate set of doped alloy elements.

[0028] In some preferred embodiments of the present invention, when the screened eutectic point composition is a ternary eutectic point composition composed of three alloy elements A, B, and C, a eutectic high-entropy alloy system composed of six alloy elements is formed according to the predefined atomic molar ratio content, and the eutectic high-entropy alloy system meets the following requirements:

[0029] Its chemical composition expression is A a B b C c D d E e F f ; where A is the key alloy element, a is the atomic molar ratio content of element A, 30% ≤ a% ≤ 54%; B and C are the two alloy elements other than the key alloy element in the eutectic point composition, b is the atomic molar ratio content of element B, 0% < b% ≤ x, and x is the atomic molar ratio content of element B in the eutectic point composition; c is the atomic molar ratio content of element C, 0% < c% ≤ y + 1, and y is the atomic molar ratio content of element C in the eutectic point composition; D and E are alloy elements that can be infinitely solid-solved with the key alloy element, d is the atomic molar ratio content of element D, 0% < d% ≤ 15%; e is the atomic molar ratio content of element E, 0% < e% ≤ 30%; F is an alloy element having a eutectic tendency with the key alloy element, f is the atomic molar ratio content of element F, 0% < f% ≤ 30%; and a + b + c + d + e + f = 100.

[0030] Step 6, preliminary screening:

[0031] Taking the valence electron concentration VEC satisfying 6.5 < VEC < 8.38 and the mixing enthalpy satisfying -18 < ΔHmix < -6 as constraints, screen the candidate set of the layer / rod eutectic high-entropy alloy to obtain the candidate layer / rod eutectic high-entropy alloy.

[0032] Step 7, final screening:

[0033] Determine the phase composition of the eutectic two phases of the candidate layer / rod eutectic high-entropy alloy. Taking the melting point difference of the phase composition of the eutectic two phases ≤ 35°C as a constraint, screen the candidate layer / rod eutectic high-entropy alloy, and thus obtain the layer / rod eutectic high-entropy alloy.

[0034] In some preferred embodiments of the present invention, the melting point difference of the eutectic two phases is obtained through the following steps:

[0035] Calculate the melting point difference corresponding to the phase composition of the eutectic two phases through the JMatPro solidification simulation phase diagram.

[0036] In some preferred embodiments of the present invention, the phase composition of the eutectic two phases of the candidate layer / rod eutectic high-entropy alloy is determined through the following steps:

[0037] Simulate the X-ray diffraction spectrum of the candidate layer / rod eutectic high-entropy alloy through Jade software, and analyze the obtained X-ray diffraction spectrum to determine the phase composition of the two phases.

[0038] The present invention also provides a layer / rod eutectic high-entropy alloy designed based on the above design method. The layer / rod eutectic high-entropy alloy is based on the ternary eutectic point composition composed of three alloy elements A, B, and C as the matrix, and is obtained by introducing doping alloy elements D, E, and F. The chemical composition expression of the layer / rod eutectic high-entropy alloy is A a B b C c D d E e F f ; where A is the key alloy element, a is the atomic molar ratio content of element A, 30% ≤ a% ≤ 54%; b is the atomic molar ratio content of element B, 0% < b% ≤ x, and x is the atomic molar ratio content of element B in the eutectic point composition; c is the atomic molar ratio content of element C, 0% < c% ≤ y + 1, and y is the atomic molar ratio content of element C in the eutectic point composition; D and E are alloy elements that can be infinitely solid-solved with the key alloy element, d is the atomic molar ratio content of element D, 0% < d% ≤ 15%; e is the atomic molar ratio content of element E, 0% < e% ≤ 30%; F is an alloy element having a eutectic tendency with the key alloy element, f is the atomic molar ratio content of element F, 0% < f% ≤ 30%; and a + b + c + d + e + f = 100.

[0039] In some preferred embodiments of the present invention, the layer / rod eutectic high-entropy alloy has a two-phase structure consisting of a first phase and a second phase; wherein the first phase is a BCC phase or an FCC phase; and the second phase is a Laves phase.

[0040] In some preferred embodiments of the present invention, the layer / rod-shaped eutectic high-entropy alloy is an iron-based eutectic high-entropy alloy, and its chemical composition is Fe. a Al b Ta c Co d Cr e Ni f Wherein, a is the atomic molar ratio of Fe, 30% ≤ a% ≤ 54%; b is the atomic molar ratio of Al, 3% ≤ b% ≤ 8%; c is the atomic molar ratio of Ta, 5% ≤ c% ≤ 8%; d is the atomic molar ratio of Co, 5% ≤ d% ≤ 15%; e is the atomic molar ratio of Cr, 20% ≤ e% ≤ 30%; f is the atomic molar ratio of Ni, 5% ≤ f% ≤ 30%; and a + b + c + d + e + f = 100. In some more preferred embodiments of the present invention, the layer / rod eutectic high-entropy alloy has a eutectic alloy microstructure of BCC phase + Laves phase, wherein the BCC phase is Fe2AlCr phase, and the Laves phase is hexagonal close-packed Fe2Ta. In some other preferred embodiments of the present invention, the layer / rod eutectic high-entropy alloy has a eutectic alloy microstructure of FCC+Laves phase, wherein the FCC phase is Fe3Ni phase and the Laves phase is hexagonal close-packed Fe2Ta.

[0041] The present invention also provides a method for preparing the above-mentioned layer / rod eutectic high-entropy alloy, comprising the following steps:

[0042] S1. According to the stoichiometric relationship of the chemical composition of the layer / rod eutectic high-entropy alloy obtained by the above design of the present invention, weigh out the corresponding mass of each preparation raw material for later use.

[0043] S2, place the weighed raw materials in a non-consumable arc melting water-cooled copper crucible in order of increasing melting point.

[0044] S3, after vacuuming, is filled with protective gas, deoxygenated, and then subjected to non-consumable arc melting to obtain molten liquid.

[0045] S4. After casting the molten liquid, the layer / rod eutectic high-entropy alloy is obtained.

[0046] In some preferred embodiments of the present invention, the non-consumable arc melting process is performed at least 5 times; and during each process, the current is controlled at 600A to 650A and the duration is 3min to 5min.

[0047] In some preferred embodiments of the present invention, the protective gas is argon with a purity ≥ 99.999 wt.%.

[0048] In some preferred embodiments of the present invention, the vacuuming process is performed to a vacuum degree ≤ 1 × 10⁻⁶. -3 Pa.

[0049] In some preferred embodiments of the present invention, the deoxygenation treatment involves placing the sponge titanium and various preparation raw materials in a non-consumable arc melting water-cooled copper crucible, and then melting the sponge titanium for 2 to 3 minutes to remove residual oxygen in the furnace.

[0050] In some preferred embodiments of the present invention, the purity of each raw material is ≥99.95%; each raw material is in block or granular form.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] This invention establishes a database based on publicly available literature data on the alloy composition and eutectic microstructure of eutectic alloy systems. Specifically, it uses the corresponding data on eutectic microstructure as input and the alloy composition of the eutectic alloy system as output. This database allows for filtering of eutectic alloy systems with lamellar and / or rod-shaped eutectic microstructures as input and constraints. The database is then used to obtain data on eutectic alloy systems exhibiting lamellar and / or rod-shaped eutectic microstructures. Furthermore, by obtaining the eutectic point composition of each eutectic alloy system in the candidate set, alloy compositions capable of forming lamellar and / or rod-shaped eutectic microstructures are obtained. These alloy compositions serve as the basic candidate set of alloying elements to ensure that the obtained alloy compositions can achieve the formation of lamellar and / or rod-shaped eutectic microstructures. This invention uses the most abundant alloying element in the eutectic point composition as the key alloying element to refine the eutectic microstructure and enhance overall strength and plasticity. Then, using the types of alloying elements that can be infinitely dissolved in solid solution and / or have a eutectic tendency with the key alloying element as constraints, the database is screened to obtain a candidate set of doped alloying elements. Several doped alloying elements selected from the candidate set are used as doping sources to partially replace the key alloying element in the basic candidate set, forming a eutectic high-entropy alloy system composed of at least five alloying elements according to a predefined atomic molar ratio. This ensures that the added doped alloying elements can improve the strength and plasticity of the key alloying element after introduction. Finally, using valence electron concentration and mixing enthalpy as criteria, and the melting point difference between the two eutectic phases as an auxiliary criterion, it is ensured that the chemical composition of the obtained layer / rod eutectic high-entropy alloy can be used to prepare the corresponding layer / rod eutectic high-entropy alloy sheet by melting.

[0053] This invention is simple to operate, requiring no complex calculations or formula derivations, nor secondary design. It can quickly determine the range in which the alloy system forms a eutectic, and directly obtain a non-equimolar ratio near / full eutectic high-entropy alloy composition with lamellar eutectic and / or rod-shaped eutectic microstructures. Furthermore, the design of this invention can simultaneously improve the strength and plasticity of high-entropy alloys, resulting in a non-equimolar ratio near / full eutectic high-entropy alloy composition with high strength and high toughness.

[0054] The design method of this invention is based on the experimental results reported in previous literature and has a theoretical basis. It can obtain multiple high-entropy amorphous alloy compositions at one time, realize the design of eutectic high-entropy alloys, has high design efficiency and high success probability, and reduces the workload of trial and error. Attached Figure Description

[0055] Figure 1 Fe as described in Example 1 50 Al8Ta7Co5Cr 25Scanning electron microscope image of Ni5.

[0056] Figure 2 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 Bright-field image of Ni5 obtained by transmission scanning electron microscopy.

[0057] Figure 3 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 X-ray diffraction pattern of Ni5.

[0058] Figure 4 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 The endothermic curve of Ni5 obtained by differential scanning calorimetry.

[0059] Figure 5 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 Compressive stress-strain curve of Ni5.

[0060] Figure 6 Fe for Example 2 45 Al8Ta7Co 10 Cr 20 Ni 10 Scanning electron microscope image.

[0061] Figure 7 Fe for Comparative Example 1 55 Al8Ta7Co5Cr 20 Scanning electron microscope image of Ni5.

[0062] Figure 8 Fe for Example 3 38.4 Al 3.625 Ta 7.4 Co8Cr 21.75 Ni 20.825 Scanning electron microscope image.

[0063] Figure 9 Fe for Example 3 38.4 Al 3.625 Ta 7.4 Co8Cr 21.75 Ni 20.825 The X-ray diffraction pattern.

[0064] Figure 10 Fe for Example 4 36 Al7Ta9Co 10 Cr 19Ni 19 Scanning electron microscope image.

[0065] Figure 11 Fe for Comparative Example 2 36 Al7Ta9Co 10 Cr 19 Ni 19 Scanning electron microscope image.

[0066] Figure 12 Fe for Comparative Example 2 36 Al7Ta9Co 10 Cr 19 Ni 19 The X-ray diffraction pattern. Detailed Implementation

[0067] The present invention will take iron-based eutectic high-entropy alloys as an example, and will clearly and completely describe the technical solutions in the embodiments of the invention through the following examples in conjunction with the accompanying drawings.

[0068] This invention provides a design method for layered / rod-shaped eutectic high-entropy alloys, comprising the following steps:

[0069] Step 1, Create a database:

[0070] To establish a database, we will obtain publicly available literature data on the alloy composition and eutectic microstructure of eutectic alloy systems. The alloy composition includes the eutectic point composition, which includes the types of alloying elements at the eutectic point and their corresponding contents.

[0071] Step 2, determine the candidate set of basic alloying elements:

[0072] 2.1) Using the constraint that the microstructure includes both lamellar eutectic and / or rod-shaped eutectic, the database is screened to obtain a candidate set of eutectic alloy systems that simultaneously have lamellar eutectic and rod-shaped eutectic.

[0073] 2.3) Obtain the eutectic point composition of each eutectic alloy system in the candidate set of the eutectic alloy system. Since Fe-Al-Ta has a ternary eutectic, and the eutectic point is Fe... 85 Al8Ta7, therefore with Fe 85 Al8Ta7 is a candidate set of basic alloying elements.

[0074] Step 3, Identify key alloying elements:

[0075] Obtain Fe 85The types and contents of alloying elements in Al8Ta7 are sorted in descending order of content as follows: Fe 85%, Al 8%, Ta 7%. That is, the key alloying element is Fe, the alloying element with the highest content.

[0076] Step 4, determine the doping alloying elements:

[0077] Since Cr elements can be infinitely solid - solved with Fe, Co is close to Fe and Cr in chemical properties, and the addition of Co can reduce the melting - point difference between two phases, Co and Cr are alloying elements that can be infinitely solid - solved with the key alloying element; Ni has a eutectic tendency with Fe, so Co, Cr, and Ni elements are used together as doping alloying elements.

[0078] Step 5, establish a candidate set of layer / rod - shaped eutectic high - entropy alloys:

[0079] Using Co, Cr, and Ni elements together as doping sources, partially replace Fe in 85 Fe in Al8Ta7. The chemical composition expression of the predefined layer / rod - shaped eutectic high - entropy alloy is Fe a Al b Ta c Co d Cr e Ni f ; where a is the atomic molar ratio content of Fe element, 30% ≤ a% ≤ 54%; b is the atomic molar ratio content of Al element, 0% < b% ≤ 8%; c is the atomic molar ratio content of Ta element, 0% < c% ≤ 8%; d is the atomic molar ratio content of Co element, 0% < d% ≤ 15%; e is the atomic molar ratio content of Cr element, 0% < e% ≤ 30%; f is the atomic molar ratio content of Ni element, 0% < f% ≤ 30%; and a + b + c + d + e + f = 100.

[0080] Step 6, preliminary screening:

[0081] Using the valence electron concentration VEC satisfying 6.5 < VEC < 8.38 and the mixing enthalpy satisfying - 18 < ΔHmix < - 6 as constraint conditions, screen the candidate set of layer / rod - shaped eutectic high - entropy alloys to obtain candidate layer / rod - shaped eutectic high - entropy alloys.

[0082] Step 7, final screening:

[0083] Simulate the X - ray diffraction pattern of the candidate layer / rod - shaped eutectic high - entropy alloy through Jade software. By analyzing the obtained X - ray diffraction pattern, determine the phase composition of the eutectic two - phase; using the melting - point difference of the phase composition of the eutectic two - phase ≤ 35°C as a constraint condition, screen the candidate layer / rod - shaped eutectic high - entropy alloy, and then the layer / rod - shaped eutectic high - entropy alloy is obtained.

[0084] The chemical composition expression of the layer / rod eutectic high-entropy alloy finally obtained by the above design method of the present invention is Fe a Al b Ta c Co d Cr e Ni f ; where a is the atomic molar ratio content of Fe element, 30% ≤ a% ≤ 54%; b is the atomic molar ratio content of Al element, 3% ≤ b% ≤ 8%; c is the atomic molar ratio content of Ta element, 5% ≤ c% ≤ 8%; d is the atomic molar ratio content of Co element, 5% ≤ d% ≤ 15%; e is the atomic molar ratio content of Cr element, 20% ≤ e% ≤ 30%; f is the atomic molar ratio content of Ni element, 5% ≤ f% ≤ 30%; and a + b + c + d + e + f = 100.

[0085] Example 1

[0086] In this example, the Fe 50 Al8Ta7Co5Cr 25 Ni5 eutectic high-entropy alloy obtained based on the above design method is taken as an example. Through calculation, it can be known that the valence electron concentration VEC of the Fe 50 Al8Ta7Co5Cr 25 Ni5 eutectic high-entropy alloy in this example is 7.04, and the mixing enthalpy ΔHmix = -8.3636, that is, the valence electron concentration VEC in this example satisfies 6.5 < VEC < 8.38, and the mixing enthalpy ΔHmix satisfies -18 < ΔHmix < -6. And the melting point difference between the two phases calculated by the JMatPro solidification simulation phase diagram is 14°C.

[0087] The Fe 50 Al8Ta7Co5Cr 25 Ni5 in this example also satisfies 30% ≤ a% ≤ 54%, 3% ≤ b% ≤ 8%, 5% ≤ c% ≤ 8%, 5% ≤ d% ≤ 15%, 20% ≤ e% ≤ 30%, 5% ≤ f% ≤ 30%; and a + b + c + d + e + f = 100.

[0088] This example also provides a preparation method for the above Fe 50 Al8Ta7Co5Cr 25 Ni5 eutectic high-entropy alloy, including the following steps:

[0089] 1) After polishing and cleaning the bulk or granular pure metals of Fe, Al, Ta, Co, Cr, and Ni with a purity of not less than 99.95% by an electronic balance, according to the atomic molar ratio of 50%:8%:7%:5%:25%:5%, respectively weigh a total mass of 130 ± 0.5 g of mixed raw materials.

[0090] 2) Place the raw materials in the non-consumable arc melting water-cooled copper crucible in order of increasing melting point. Then, evacuate the furnace until the vacuum level reaches 1×10⁻⁶. -3 After Pa, argon gas with a purity of 99.999 wt.% is introduced into the vacuum non-consumable arc melting furnace as a protective gas for melting. Before melting the raw materials, sponge titanium is melted for two to three minutes. The current is controlled at 600-650 A, and to ensure uniform composition, the high-entropy alloy ingot is turned over at least five times. After melting, the molten liquid is turned over into a copper mold to obtain a high-entropy alloy plate, thus obtaining a eutectic high-entropy alloy sample.

[0091] The present invention relates to the Fe prepared by the above-described preparation method in this embodiment. 50 Al8Ta7Co5Cr 25 The Ni5 eutectic high-entropy alloy was subjected to scanning electron microscopy testing, and the test results are as follows: Figure 1 As shown.

[0092] Figure 1 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 Scanning electron microscope images of Ni5 eutectic high-entropy alloy, by Figure 1 It can be seen that the Fe prepared in Example 1 50 Al8Ta7Co5Cr 25 The formation of extremely fine, complete eutectic cells in the Ni5 eutectic high-entropy alloy indicates that the Fe prepared in Example 1... 50 Al8Ta7Co5Cr 25 The microstructure of Ni5 eutectic high-entropy alloy consists of layered and rod-shaped eutectic structures.

[0093] The present invention relates to the Fe prepared by the above-described preparation method in this embodiment. 50 Al8Ta7Co5Cr 25 The Ni5 eutectic high-entropy alloy was subjected to transmission scanning electron microscopy (TEM) testing, and the test results are as follows: Figure 2 As shown.

[0094] Figure 2 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 Bright-field images of the Ni5 eutectic high-entropy alloy obtained by transmission scanning electron microscopy clearly show that the Fe prepared in Example 1... 50 Al8Ta7Co5Cr 25 The unit cell of Ni5 eutectic high-entropy alloy consists of regular layers and rod-shaped eutectic structures.

[0095] The present invention relates to the Fe prepared by the above-described preparation method in this embodiment. 50 Al8Ta7Co5Cr 25X-ray diffraction tests were performed on the Ni5 eutectic high-entropy alloy, and the test results are as follows: Figure 3 As shown.

[0096] Figure 3 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 The X-ray diffraction pattern of the Ni5 eutectic high-entropy alloy shows that Fe 50 Al8Ta7Co5Cr 25 The phase composition of the Ni5 eutectic high-entropy alloy consists of a BCC-structured Fe2AlCr phase and a close-packed hexagonal Fe2Ta-structured Laves phase.

[0097] The present invention relates to the Fe prepared by the above-described preparation method in this embodiment. 50 Al8Ta7Co5Cr 25 The temperature rise and endothermic curve of Ni5 eutectic high-entropy alloy obtained by differential scanning calorimetry is shown in the figure, and the test results are as follows: Figure 4 As shown.

[0098] Figure 4 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 The heating and endothermic curve of the Ni5 eutectic high-entropy alloy shows a single, narrow endothermic peak, which confirms the presence of Fe in Example 1. 50 Al8Ta7Co5Cr 25 Ni5 eutectic high-entropy alloy is indeed a eutectic high-entropy alloy, and it has regular layered rod-like eutectic characteristics.

[0099] This invention employs wire electrical discharge machining (EDM) to cut Fe from Example 1. 50 Al8Ta7Co5Cr 25 Rectangular specimens with dimensions of 10×10×20mm were cut from Ni5 high-entropy alloy sheet. The specimen surfaces were then successively polished with 120#, 240#, 400#, 800#, 1000#, 1500#, and 2000# metallographic sandpaper. The compressive properties of the specimens in Example 1 were then tested using a universal testing machine. The test results are as follows: Figure 5 As shown.

[0100] Figure 5 Fe as described in Example 1 50 Al8Ta7Co5Cr 25 The compressive stress-strain curve of Ni5 shows that the Fe in Example 1... 50 Al8Ta7Co5Cr 25 Ni5 has a yield strength of 1669.2 MPa and a fracture strength of 1958.4 MPa, with a fracture strain as high as 16.2%, exhibiting good plasticity.

[0101] Example 2

[0102] This example takes the Fe 45 Al8Ta7Co 10 Cr 20 Ni 10 eutectic high-entropy alloy obtained based on the above design method as an example. Through calculation, it can be known that the valence electron concentration VEC of the Fe 45 Al8Ta7Co 10 Cr 20 Ni 10 eutectic high-entropy alloy is VEC = 7.29, and the mixing enthalpy ΔHmix = -9.4736. That is, the valence electron concentration VEC of this example satisfies 6.5 < VEC < 8.38, and the mixing enthalpy ΔHmix satisfies -18 < ΔHmix < -6. And the melting point difference between the two phases calculated by the JMatPro solidification simulation phase diagram is 14 °C.

[0103] The Fe 45 Al8Ta7Co 10 Cr 20 Ni 10 in this example also satisfies 30% ≤ a% ≤ 54%, 3% ≤ b% ≤ 8%, 5% ≤ c% ≤ 8%, 5% ≤ d% ≤ 15%, 20% ≤ e% ≤ 30%, 5% ≤ f% ≤ 30%; and a + b + c + d + e + f = 100.

[0104] This example also provides a preparation method for the above Fe 45 Al8Ta7Co 10 Cr 20 Ni 10 eutectic high-entropy alloy, including the following steps:

[0105] 1) After polishing and cleaning the bulk or granular pure metals of Fe, Al, Ta, Co, Cr, and Ni with a purity of not less than 99.95% by an electronic balance, weigh the mixed raw materials with a total mass of 130 ± 0.5 g at a molar ratio of 45:8:7:10:20:10 respectively.

[0106] 2) Place the raw materials in a non-consumable arc melting water-cooled copper crucible in ascending order of melting point. Then evacuate to a vacuum degree of 1×10 -3 Pa in the furnace cavity, and then fill the vacuum non-consumable arc melting furnace with argon with a purity of 99.999 wt.% as the protective gas for melting. Before melting the raw materials, first melt the sponge titanium for two to three minutes. Control the current at 600 - 650 A. To ensure the uniformity of the composition, the high-entropy alloy ingot is remelted at least 5 times. After melting, turn the molten liquid into a copper mold to obtain a high-entropy alloy plate and get a eutectic high-entropy alloy sample.

[0107] The present invention performed scanning electron microscope tests on the eutectic high-entropy alloy of Fe 45 Al8Ta7Co 10 Cr 20 Ni 10 and the test results are as Figure 6 shown.

[0108] Figure 6 For the Fe 45 Al8Ta7Co 10 Cr 20 Ni 10 eutectic high-entropy alloy of Example 2, as can be seen from Figure 6 the scanning electron microscope image, in the Fe 45 Al8Ta7Co 10 Cr 20 Ni 10 eutectic high-entropy alloy prepared in Example 2, extremely fine and complete eutectic cells are formed, but there are still a small amount of primary phases.

[0109] Comparative Example 1

[0110] Taking the Fe 55 Al8Ta7Co5Cr 20 Ni5 eutectic high-entropy alloy as an example, through calculation, the valence electron concentration VEC of the Fe 50 Al8Ta7Co5Cr 25 Ni5 eutectic high-entropy alloy in this example is 7.14, and the mixing enthalpy ΔHmix = -8.3856, that is, the valence electron concentration VEC in this example satisfies 6.5 < VEC < 8.38, and the mixing enthalpy ΔHmix satisfies -18 < ΔHmix < -6. And the melting point difference between the two phases calculated by the JMatPro solidification simulation phase diagram is 20°C. Although the alloy composition of this comparative example also meets the design requirements, the Fe content does not meet the requirement of 30% ≤ a% ≤ 54% mentioned above.

[0111] And the preparation method of this comparative example is the same as that of Example 1, the difference is only that:

[0112] the eutectic high-entropy alloy of this comparative example is the Fe 55 Al8Ta7Co5Cr 20 Ni5 eutectic high-entropy alloy.

[0113] The present invention performed scanning electron microscope tests on the Fe 55 Al8Ta7Co5Cr 20 Ni5 eutectic high-entropy alloy prepared by the above preparation method of this comparative example, and the test results are as Figure 7 shown.

[0114] Figure 7 For the Fe of Comparative Example 1 55 Al8Ta7Co5Cr 20 Scanning electron microscope image of the Ni5 eutectic high-entropy alloy, from Figure 7 It can be seen that for the Fe of Comparative Example 1 55 Al8Ta7Co5Cr 20 In the Ni5 eutectic high-entropy alloy, large Laves primary phases appeared, and the alloy composition deviated from the eutectic, forming a hypoeutectic structure. This indicates that when the content of key alloying elements exceeds

[0115] Example 3

[0116] This example takes the Fe 38.4 Al 3.625 Ta 7.4 Co8Cr 21.75 Ni 20.825 eutectic high-entropy alloy obtained based on the above design method as an example. Through calculation, it can be known that the valence electron concentration VEC of the Fe 38.4 Al 3.625 Ta 7.4 Co8Cr 21.75 Ni 20.825 eutectic high-entropy alloy is VEC = 7.658, and the mixing enthalpy ΔHmix = -11.708. That is, the valence electron concentration VEC of this example satisfies 6.5 < VEC < 8.38, and the mixing enthalpy ΔHmix satisfies -18 < ΔHmix < -6. And the melting point difference between the two phases calculated by the JMatPro solidification simulation phase diagram is 34 °C.

[0117] The Fe of this example​​​​​​​​​​​​​​​​​​​​​​​​​1) After cleaning the block or granular pure metals Fe, Al, Ta, Co, Cr and Ni with a purity of not less than 99.95% by grinding and cleaning them with an electronic balance, weigh out a total of 130±0.5g of mixed raw materials with an atomic ratio of 38.4:3.625:7.4:8:21.75:20.825.

[0120] 2) Place the raw materials in the non-consumable arc melting water-cooled copper crucible in order of increasing melting point. Then, evacuate the furnace until the vacuum level reaches 1×10⁻⁶. -3 After Pa, argon gas with a purity of 99.999 wt.% is introduced into the vacuum non-consumable arc melting furnace as a protective gas for melting. Before melting the raw materials, sponge titanium is melted for two to three minutes. The current is controlled at 600-650 A, and to ensure uniform composition, the high-entropy alloy ingot is turned over at least five times. After melting, the molten liquid is turned over into a copper mold to obtain a high-entropy alloy plate, thus obtaining a eutectic high-entropy alloy sample.

[0121] The present invention relates to the Fe prepared by the above-described preparation method in this embodiment. 38.4 Al 3.625 Ta 7.4 Co8Cr 21.75 Ni 20.825 The eutectic high-entropy alloy was subjected to scanning electron microscopy testing, and the test results are as follows: Figure 8 As shown.

[0122] Figure 8 Fe for Example 3 38.4 Al 3.625 Ta 7.4 Co8Cr 21.75 Ni 20.825 Scanning electron microscope images of eutectic high-entropy alloys, by Figure 8 It can be seen that the Fe prepared in Example 3 38.4 Al 3.625 Ta 7.4 Co8Cr 21.75 Ni 20.825 Extremely fine and complete eutectic cells are formed in the eutectic high-entropy alloy. The cells of this high-entropy alloy are composed of regular layers and rod-shaped eutectic structures.

[0123] The present invention relates to the Fe prepared by the above-described preparation method in this embodiment. 38.4 Al 3.625 Ta 7.4 Co8Cr 21.75 Ni 20.825 X-ray diffraction tests were performed on the eutectic high-entropy alloy, and the test results are as follows: Figure 9 As shown.

[0124] Figure 9 Fe for Example 338.4 Aluminum 3.625 Tantalum 7.4 Co8Cr 21.75 Nickel 20.825 For the X-ray diffraction pattern of the eutectic high-entropy alloy, it can be seen that Fe 38.4 Aluminum 3.625 Tantalum 7.4 Co8Cr 21.75 Nickel 20.825 The phase composition structure of the eutectic high-entropy alloy consists of the Fe3Ni phase with a face-centered cubic (FCC) structure and the Laves phase with a hexagonal close-packed Fe2Ta configuration.

[0125] Example 4

[0126] In this example, taking the Fe 32 Aluminum 3.5 Ta8Co8Cr 26 Nickel 22.5 eutectic high-entropy alloy as an example, through calculation, it can be known that the valence electron concentration VEC of the Fe 32 Aluminum 3.5 Ta8Co8Cr 26 Nickel 22.5 eutectic high-entropy alloy in this example is VEC = 7.658, and the mixing enthalpy ΔHmix = -12.618. That is, the valence electron concentration VEC in this example satisfies 6.5 < VEC < 8.38, and the mixing enthalpy ΔHmix satisfies -18 < ΔHmix < -6. And the melting point difference between the two phases calculated by the JMatPro solidification simulation phase diagram is 13 °C.

[0127] The Fe 32 Aluminum 3.5 Ta8Co8Cr 26 Nickel 22.5 in this example also satisfies 30% ≤ a% ≤ 54%, 3% ≤ b% ≤ 8%, 5% ≤ c% ≤ 8%, 5% ≤ d% ≤ 15%, 20% ≤ e% ≤ 30%, 5% ≤ f% ≤ 30%; and a + b + c + d + e + f = 100.

[0128] This example also provides a preparation method for the above-mentioned Fe 32 Aluminum 3.5 Ta8Co8Cr 26 Nickel 22.5 eutectic high-entropy alloy, including the following steps:

[0129] 1) After polishing and cleaning the bulk or granular pure metals of Fe, Al, Ta, Co, Cr, and Ni with a purity of not less than 99.95% by an electronic balance, weigh the mixed raw materials with a total mass of 130 ± 0.5 g at a molar ratio of 32:3. .5:8:8:26:22.5 respectively.

[0130] (2) Place the raw materials in a non-consumable arc melting water-cooled copper crucible in order of increasing melting point. Then evacuate to a vacuum degree of 1×10 -3 Pa in the furnace cavity, and then fill the vacuum non-consumable arc melting furnace with argon with a purity of 99.999 wt.% as the protective gas for melting. Before melting the raw materials, first melt the titanium sponge for two to three minutes. Control the current at 600 - 650 A. To ensure uniform composition, the high-entropy alloy ingot is remelted at least 5 times. After melting, pour the molten liquid into a copper mold to obtain a high-entropy alloy plate, and obtain a eutectic high-entropy alloy sample.

[0131] The present invention conducts a scanning electron microscope test on the Fe 32 Al 3.5 Ta8Co8Cr 26 Ni 22.5 eutectic high-entropy alloy prepared by the above preparation method of this embodiment, and the test results are as Figure 10 shown.

[0132] Figure 10 For the Fe 32 Al 3.5 Ta8Co8Cr 26 Ni 22.5 scanning electron microscope image of the eutectic high-entropy alloy in Example 4, it can be seen from Figure 10 that in the Fe 32 Al 3.5 Ta8Co8Cr 26 Ni 22.5 eutectic high-entropy alloy prepared in Example 4, extremely fine and complete eutectic cells are formed, but there are still a small amount of primary phases.

[0133] Comparative Example 2

[0134] This comparative example takes the Fe 36 Al7Ta9Co 10 Cr 19 Ni 19 eutectic high-entropy alloy obtained by the above design method as an example. Through calculation, it can be known that the valence electron concentration VEC of the Fe 36 Al7Ta9Co 10 Cr 19 Ni 19 eutectic high-entropy alloy in this comparative example is 7.48, and the mixing enthalpy ΔHmix = -12.798, that is, the valence electron concentration VEC of this comparative example satisfies 6.5 < VEC < 8.38, and the mixing enthalpy ΔHmix satisfies -18 < ΔHmix < -6. And the melting point difference between the two phases calculated by the JMatPro solidification simulation phase diagram is 14 °C. But it does not satisfy 5% ≤ c% ≤ 8%.

[0135] The preparation method of this comparative example is the same as that of Example 1, except that:

[0136] The eutectic high-entropy alloy in this comparative example is Fe. 36 Al7Ta9Co 10 Cr 19 Ni 19 Eutectic high-entropy alloy.

[0137] The present invention relates to Fe prepared by the above preparation method in the comparative example. 36 Al7Ta9Co 10 Cr 19 Ni 19 The eutectic high-entropy alloy was subjected to scanning electron microscopy testing, and the test results are as follows: Figure 11 As shown.

[0138] Figure 11 Fe for Comparative Example 2 36 Al7Ta9Co 10 Cr 19 Ni 19 Scanning electron microscope images of eutectic high-entropy alloys, by Figure 11 It can be seen that the Fe prepared in Comparative Example 2 36 Al7Ta9Co 10 Cr 19 Ni 19 Eutectic high-entropy alloys contain a large amount of Laves primary phase and a small amount of eutectic structure, and the alloy composition deviates from the eutectic point.

[0139] The present invention relates to Fe prepared by the above preparation method in the comparative example. 36 Al7Ta9Co 10 Cr 19 Ni 19 X-ray diffraction tests were performed on the eutectic high-entropy alloy, and the test results are as follows: Figure 12 As shown.

[0140] Figure 12 Fe for Comparative Example 2 36 Al7Ta9Co 10 Cr 19 Ni 19 The X-ray diffraction pattern of the eutectic high-entropy alloy shows that Fe... 36 Al7Ta9Co 10 Cr 19 Ni 19 The phase composition of the eutectic high-entropy alloy consists of an FCC-structured Fe3Ni phase and a close-packed hexagonal Fe2Ta-structured Laves phase.

[0141] It should be noted that, in performing the above-mentioned scanning electron microscope (SEM) and transmission electron microscope (TEM) tests, the present invention first uses wire electrical discharge machining (EDM) to cut a cross-sectional sample with dimensions of 10×20×4mm from the high-entropy alloy plate. The sample surface is then polished with 120#, 240#, 400#, 800#, 1000#, 1500#, and 2000# metallographic sandpaper in sequence, and then polished before performing the SEM and TEM tests.

[0142] In performing the above-mentioned X-ray diffraction test, the scanning angle is 20° to 100° and the scanning speed is 0.02° / s.

[0143] In performing the differential scanning calorimetry test described above, the heating rate was 10 K / min and the termination temperature was 1450 °C.

[0144] Obviously, the above embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A design method for layered / rod-shaped eutectic high-entropy alloys, characterized in that, It includes the following steps: Obtain the alloy composition and eutectic microstructure morphology of the eutectic alloy system in the publicly available literature data, and establish a database with the corresponding data of the eutectic microstructure morphology as input data and the alloy composition of the eutectic alloy system as the corresponding output data; Taking the microstructure morphology including lamellar eutectic and / or rod eutectic as a constraint condition, screen the database to obtain a candidate set of eutectic alloy systems with lamellar eutectic and / or rod eutectic; obtain the eutectic point composition of each eutectic alloy system in the candidate set of eutectic alloy systems as the candidate set of basic alloy elements; Obtain the types and contents of alloy elements with eutectic point composition in the candidate set of basic alloy elements, sort the types of alloy elements with eutectic point composition in descending order of content, and take the alloy element type with the largest content as the key alloy element; Taking the types of alloy elements that can be infinitely solid-soluble and / or have a eutectic tendency with the key alloy element as a constraint condition, screen the database to obtain a candidate set of doped alloy elements; Taking several doped alloy elements selected from the candidate set of doped alloy elements as doping sources, partially replace the key alloy element in the candidate set of basic alloy elements, and form a eutectic high-entropy alloy system composed of at least five alloy elements according to the predefined atomic molar ratio content, and establish a candidate set of lamellar / rod eutectic high-entropy alloys; Taking the valence electron concentration VEC satisfying 6.5 < VEC < 8.38 and the mixing enthalpy ΔHmix satisfying -18 < ΔHmix < -6 as constraint conditions, screen the candidate set of lamellar / rod eutectic high-entropy alloys to obtain candidate lamellar / rod eutectic high-entropy alloys; Determine the phase composition of the eutectic two phases of the candidate lamellar / rod eutectic high-entropy alloy, and screen the candidate lamellar / rod eutectic high-entropy alloy with the melting point difference between the eutectic two phases satisfying ≤35°C, and the lamellar / rod eutectic high-entropy alloy is obtained; When the eutectic point composition obtained by screening is the ternary eutectic point composition composed of three alloy elements A, B and C, form a eutectic high-entropy alloy system composed of six alloy elements according to the predefined atomic molar ratio content, and the eutectic high-entropy alloy system meets the following requirements: Its chemical composition formula is A a B b C c D d E e F f ; Among them, A is the key alloy element, a is the atomic molar ratio content of element A, 30% ≤ a% ≤ 54%; b represents the atomic molar percentage of element B, 0% <b%≤ x , x is the atomic molar ratio of element B in the eutectic point composition; c is the atomic molar ratio of element C, 0%. <c%≤ y+ 1, y This represents the atomic molar ratio of carbon element in the eutectic point composition. D and E are alloy elements that can be infinitely solid-soluble with the key alloy element, d is the atomic molar ratio content of element D, 0% < d% ≤ 15%; e is the atomic molar ratio content of element E, 0% < e% ≤ 30%; F is an alloy element that has a eutectic tendency with the key alloy element, f is the atomic molar ratio content of element F, 0% < f% ≤ 30%; And a + b + c + d + e + f = 100; Among them, A, B, C, D, E, F are Fe, Al, Ta, Co, Cr, Ni in turn.

2. The design method as described in claim 1, characterized in that, The melting point difference between the eutectic two phases is obtained through the following steps: Calculate the melting point difference corresponding to the phase composition of the eutectic two phases through JMatPro solidification simulation phase diagram.

3. The design method as described in claim 1, characterized in that, The phase composition of the eutectic two phases of the candidate lamellar / rod eutectic high-entropy alloy is determined through the following steps: Simulate the X-ray diffraction pattern of the candidate layer / rod eutectic high-entropy alloy by Jade software, and determine the phase composition of the eutectic two phases by analyzing the obtained X-ray diffraction pattern.

4. The design method as described in claim 1, characterized in that, Taking the conditions that the atomic radius is close to that of the key alloy element, the crystal structure is the same, and there is only a single-phase region below the liquidus in the binary phase diagram formed with the key alloy element as constraints, screen the alloy elements in the database to obtain alloy elements that can be infinitely solid-solved with the key alloy element.

5. The design method as described in claim 1, characterized in that, Taking the condition that the valence electron concentration VEC of the alloy formed with the key alloy element is ≥ 8 as a constraint, screen the alloy elements in the database to obtain alloy elements that have a eutectic tendency with the key alloy element.

6. A layered / rod-shaped eutectic high-entropy alloy designed by the design method according to any one of claims 1 to 5, characterized in that, Using a ternary eutectic composition composed of three alloying elements A, B, and C as the matrix, and by introducing doping alloying elements D, E, and F, the layer / rod-shaped eutectic high-entropy alloy is obtained, and the chemical composition expression of the alloy is A. a B b C c D d E e F f ; Among them, A is the key alloy element, a is the atomic molar ratio content of element A, 30% ≤ a% ≤ 54%; b represents the atomic molar ratio of element B, 0% <b%≤ x , x is the atomic molar ratio of element B in the eutectic point composition; c is the atomic molar ratio of element C, 0%. <c%≤ y+ 1, y This represents the atomic molar ratio of carbon element in the eutectic point composition. D and E are alloy elements that can be infinitely solid-solved with the key alloy element, d is the atomic molar ratio content of element D, 0% < d% ≤ 15%; e is the atomic molar ratio content of element E, 0% < e% ≤ 30%; F is an alloy element that has a eutectic tendency with the key alloy element, f is the atomic molar ratio content of element F, 0% < f% ≤ 30%; And a + b + c + d + e + f = 100.

7. The layer / rod eutectic high-entropy alloy as described in claim 6, characterized in that, The layer / rod eutectic high-entropy alloy has a two-phase structure composed of a first phase and a second phase; The first phase is a BCC phase or FCC; The second phase is a Laves phase.

8. A method for preparing the layer / rod eutectic high-entropy alloy according to claim 6, characterized in that, It includes the following steps: Weigh the corresponding masses of each preparation raw material according to the stoichiometric relationship of the chemical composition of the described layer / rod eutectic high-entropy alloy for standby; Place the weighed preparation raw materials in a non-consumable arc melting water-cooled copper crucible in ascending order of melting point; After vacuum pumping, fill with a protective gas, and after deoxidation treatment, perform non-consumable arc melting treatment to obtain a molten liquid; After casting the molten liquid, the layer / rod eutectic high-entropy alloy is obtained.

9. The preparation method according to claim 8, characterized in that, The non-consumable arc melting treatment is carried out at least 5 times; and each time during the treatment, the current is controlled at 600A - 650A, and the duration is 3min - 5min; The protective gas is argon with a purity ≥ 99.999wt.%; The vacuuming process is performed until the vacuum level is ≤1×10⁻⁶. -3 Pa; The deoxidation treatment is carried out by placing titanium sponge and each preparation raw material in a non-consumable arc melting water-cooled copper crucible, and first melting titanium sponge for 2min - 3min to remove residual oxygen in the furnace.

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