A titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity and its preparation and application

Abstract

The present invention discloses a titanium-based lightweight superalloy with high strength and high tensile plasticity, and its preparation and application. The chemical formula of the titanium-based lightweight superalloy is Ti a V b Nb c Al d Cr e Zr i Si j , and the titanium-based lightweight superalloy with high strength and high tensile plasticity disclosed by the present invention is designed by regulating the content of each element, the valence electron concentration and the electronegativity of the alloy according to the intrinsic characteristics of various elements. The addition of the non-alloying element Si introduces nanoscale precipitate phases into the alloy, which are uniformly distributed in the alloy matrix and interact with dislocations during the alloy deformation process, playing the role of second-phase strengthening. In summary, the alloy design idea enables the alloy to have low density, good room temperature strength and tensile plasticity, and excellent high temperature tensile properties at the same time; and has the advantages of simple operation, easy implementation, pollution-free process, low energy consumption and low cost.

Description

Technical Field

[0001] The present invention belongs to the field of multi-principal-element alloys, and in particular relates to a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity, and its preparation and application. Background Art

[0002] Lightweighting of structural materials can reduce the weight of components, improve energy efficiency, save resources, and reduce environmental pollution. It is widely used in aerospace, energy, transportation and other fields. However, the strength and plasticity of metal structural materials are usually not taken into account at the same time, and the strength generally decreases with the decrease of alloy density. With the rapid development of my country's aerospace and other fields, future equipment may face more severe service environments, especially high temperature environments, which put forward more stringent requirements on the performance of structural materials. However, traditional metal structural materials are gradually approaching performance bottlenecks under the design concept of single principal element, which limits the further development and application of conventional lightweight alloys in actual engineering fields. There is an urgent need for subversive new alloy design concepts to guide alloy design and performance regulation.

[0003] The emergence of multi-principal alloys has brought about a new alloy design concept. The supersaturated solid solution composed of multiple elements in equal or nearly equal atomic ratios and with chemically disordered atomic arrangement has provided a new design idea for the design of new lightweight materials. Since multi-principal alloys have large lattice distortion and their performance is limited by each component, they have a huge space for alloy design and development. However, since the emergence of multi-principal alloys, the systems studied are mostly based on transition elements and refractory elements. Since the density of these elements is generally large, the density of the prepared high-temperature alloys is relatively high (>8 g·cm -3 ), which limits its application in practical engineering, such as aerospace. The new lightweight high-temperature alloy developed based on the lightweight design of multi-principal alloys has outstanding characteristics such as high specific strength, low density and good corrosion resistance. These lightweight materials have shown great engineering application potential in the fields of civil aviation engines, military fighters, aerospace vehicles and other defense industries, as well as energy and transportation.

[0004] The currently studied lightweight high-temperature alloy system mainly uses light elements such as Al, Ti, and V for alloy design. Depending on the composition and content of the elements, the density is mainly distributed in the range of 1.5 - 6.5 g·cm -3range. However, due to the large difference in atomic radius of each component and the low mixing enthalpy, these lightweight alloys usually contain a large number of brittle precipitated phases (such as intermetallic compounds and ordered phases), which makes their room temperature plasticity poor and difficult to carry out subsequent processing, greatly limiting the scope of application of lightweight high-temperature alloys. Therefore, the development of lightweight high-temperature alloys that have both high strength and sufficient tensile plasticity and excellent high-temperature performance is still an important and challenging task. At the same time, it has important engineering significance for promoting the upgrading of lightweight alloy materials and promoting their industrial application. Summary of the invention

[0005] The present invention discloses a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity, as well as its preparation and application, which have solved the above-mentioned technical problems as well as other technical problems in the prior art.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: a titanium-based light high-temperature alloy with high strength and high tensile plasticity and its preparation and application, the chemical formula of the titanium-based light high-temperature alloy is Ti a V b Nb c Al d Cr e Zr i Si j The atomic ratio of each component is: 50 ≤a≤ 70 at%, 0<b ≤30 at%, 0<c≤ 20 at%, 0<d ≤25 at%, 0<e≤20at%, i≥0 at%, 0<j≤5 at%, and a+b+c+d+e+i+j =100 at%.

[0007] Furthermore, when a = 50 at%, b = 14.8 at%, c = 15 at%, d = 10 at%, e = 5 at%, i = 5 at%, j = 0.2 at%, the chemical formula of the lightweight high-temperature alloy is Ti 50 V 14.8 Nb 15 Al 10 Cr5Zr5Si 0.2 The room temperature tensile strength of the alloy is 1116 MPa, the tensile plasticity is 7.5%, the tensile strength at 800℃ is 606 MPa, the tensile plasticity is 47%, and the density is 5.392 g·cm -3 .

[0008] Furthermore, when a = 50 at%, b = 14.6 at%, c = 15 at%, d = 10 at%, e = 5 at%, i = 5 at%, j = 0.4 at%, the chemical formula of the lightweight high-temperature alloy is Ti50 V 14.6 Nb 15 Al 10 Cr5Zr5Si 0.4 The room temperature tensile strength of the alloy is 1190 MPa, the tensile plasticity is 11%, the tensile strength at 800℃ is 697 MPa, the tensile plasticity is 61%, and the density is 5.383 g·cm -3 .

[0009] Furthermore, when a = 59.6 at%, b = 8 at%, c = 9 at%, d = 13 at%, e = 5 at%, i = 5 at%, j = 0.4 at%, the chemical formula of the lightweight high-temperature alloy is Ti 59.6 V8Nb9 13 Cr5Zr5Si 0.4 The room temperature tensile strength of the alloy is 1206 MPa, the tensile plasticity is 12%, the tensile strength at 800℃ is 445 MPa, the tensile plasticity is 73%, and the density is 4.982 g·cm -3 .

[0010] Furthermore, when a = 60 at%, b = 10.4 at%, c = 10 at%, d = 13 at%, e = 5 at%, i = 0 at%, j = 1.6 at%, the chemical formula of the titanium-based lightweight high-temperature alloy is Ti 60 V 10.4 Nb 10 Al 13 Cr5Si 1.6 The room temperature tensile strength of the alloy is 1093 MPa, the tensile plasticity is 12%, the tensile strength at 800℃ is 352 MPa, the tensile plasticity is 81%, and the density is 4.899 g·cm -3 .

[0011] When a = 60 at%, b = 10.2 at%, c = 10 at%, d = 13 at%, e = 5 at%, i = 0 at%, j = 1.8 at%, the chemical formula of the lightweight high-temperature alloy is Ti 60 V 10.2 Nb 10 Al 13 Cr5Si 1.8 The room temperature tensile strength of the alloy is 1116 MPa, the tensile plasticity is 10.5%, the tensile strength at 800℃ is 359 MPa, the tensile plasticity is 88%, and the density is 4.891 g·cm -3 .

[0012] Another object of the present invention is to provide a method for preparing the above titanium-based lightweight high-temperature alloy, the steps of which are as follows:

[0013] S1) Select high-purity (≥ 99.9 wt%) metal and non-metallic single-substance raw materials, use grinding wheels and sandpaper to clean the oxide scale on the metal surface, and use ultrasonic cleaning machine to use industrial anhydrous alcohol to clean and dry the raw materials; convert the atomic percentage of each alloy component into a mass ratio, use an electronic balance to accurately weigh (accuracy of 0.001 g) the required mass of each element, and prepare the ingredients;

[0014] S2) The weighed raw materials are placed in the copper crucible of a non-consumable vacuum arc furnace (volatile elements are placed in the bottom layer) according to their melting points in ascending order (i.e., the lower melting point is placed on the bottom layer, and the higher melting point is placed on the top layer) as well as the titanium ingot; the furnace chamber is then evacuated. When the low vacuum degree reaches 1.0 × 10 0 -5.0 × 10 0 Pa, close the low vacuum valve; open the high vacuum valve, and draw a high vacuum. When the high vacuum degree reaches 1.0 × 10 -4 - 8.0 × 10 -4 When the pressure reaches 0.047 MPa, close the high vacuum valve and fill the furnace chamber with high-purity argon gas to 0.047 MPa (up and down fluctuations of 0.002 MPa are allowed). Repeat this process twice to reduce the oxygen content in the furnace chamber.

[0015] S3) arc melting is performed under the protection of high-purity argon gas. First, the titanium ingot is melted to further reduce the oxygen content in the furnace chamber. Then, the alloy raw materials of each component are melted and cooled to obtain alloy ingots. The melting time of each ingot is about 2.5 minutes. In order to obtain an alloy ingot with uniform chemical composition, after the alloy ingot is cooled after each melting, the alloy ingot is turned over by a turning shovel and tilted and placed on the crucible wall. This is repeated for a total of six meltings. Among them, after the alloy is melted three times, the furnace chamber needs to be evacuated again and filled with high-purity argon gas.

[0016] S4) After the master alloy is fully and evenly melted, it is dripped / cast into a water-cooled copper mold to finally obtain an alloy ingot of a specific shape.

[0017] When the alloy composition contains elements that are easily burned, such as Al and V, an excess of 0.05% should be added during the weighing in step 1 to compensate for the burning during the smelting process.

[0018] Furthermore, the titanium-based lightweight high-temperature alloy prepared by the method has a simple body-centered cubic structure and dispersed nanoscale precipitation phases, and the density of the alloy is 4.88-5.40 g·cm -3The tensile strength is between 843-1124 MPa, the elongation at break is greater than 10%, the tensile strength at 800℃ is between 229-697 MPa, and the elongation at break is greater than 20%.

[0019] The titanium-based lightweight high-temperature alloy is used in the fields of energy, transportation and aerospace.

[0020] The present invention mainly designs alloys by regulating the content of each element and the valence electron concentration of the alloy according to the intrinsic characteristics of each component element. Specifically, firstly, elements such as Ti, V, Nb, Al, etc. with relatively low density are selected according to the mixing rule to ensure the low density of the designed alloy. Literature research shows that V and Nb elements have good intrinsic plasticity and are added in appropriate amounts when designing the alloy. However, considering that V is not good for oxidation resistance and Nb element has a relatively high density, the addition amount of the element should be controlled. According to the design experience of BCC refractory high entropy alloys, when the valence electron concentration of the alloy system is less than 4.6, it often exhibits a certain plastic deformation ability. Therefore, when designing the alloy, the content of elements with low valence electron concentration should be as high as possible. In addition, in order to ensure that the designed alloy retains high strength, a small amount of elements with large atomic size mismatch can be added to improve the strength of the alloy by promoting solid solution strengthening. In addition, the addition of non-alloy element Si can introduce nano-scale precipitation phases into the alloy, which are evenly distributed in the alloy matrix and interact with dislocations during the deformation of the alloy to play a role in second phase strengthening. Based on the above design criteria, a titanium-based lightweight high-temperature alloy with excellent properties such as low density, high tensile strength at room temperature and high temperature, and good tensile plasticity was finally designed and prepared.

[0021] The beneficial effects of the present invention are as follows: due to the adoption of the above technical scheme, the high entropy alloy involved in the present invention is mainly designed by adjusting the content of each element and the valence electron concentration of the alloy according to the intrinsic characteristics of each component element, so that the alloy has excellent properties such as low density, high strength and good tensile plasticity at the same time, which is of great significance and great application prospects for achieving lightweight structural parts in the fields of energy, transportation, aerospace, etc.

[0022] The lightweight high-temperature alloys involved in the present invention can all be melted in a non-consumable vacuum arc furnace and directly dripped / cast to obtain alloy ingots. The preparation method is simple and easy to implement, the preparation process is pollution-free, and has low energy consumption and cost, and can realize large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a quasi-static tensile engineering stress-strain curve diagram of the titanium-based lightweight high-temperature alloy prepared in Example 2 and Example 4 of the present invention at room temperature.

[0024] Figure 2It is a quasi-static tensile engineering stress-strain curve diagram of the titanium-based lightweight high-temperature alloy prepared in Example 2 and Example 4 of the present invention at 800°C.

[0025] Figure 3 It is the X-ray diffraction spectrum of the titanium-based lightweight high-temperature alloy prepared in Example 2 and Example 4 of the present invention.

[0026] Figure 4 Ti prepared in Example 2 of the present invention 50 V 14.6 Nb 15 Al 10 Cr5Zr5Si 0.4 Scanning electron microscope image of a titanium-based lightweight superalloy.

[0027] Figure 5 Ti prepared in Example 4 of the present invention 60 V 10.4 Nb 10 Al 13 Cr5Si 1.6 Scanning electron microscope image of a titanium-based lightweight superalloy. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods, and the technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings. The following examples are only part of the embodiments of the present invention and do not fully cover the scope of the claims of the present invention.

[0029] The present invention discloses a titanium-based light high-temperature alloy with high strength and high tensile plasticity. The chemical formula of the titanium-based light high-temperature alloy is Ti a V b Nb c Al d Cr e Zr i Si j , the atomic ratio of each component is: 50≤a≤ 70 at%, 0<b ≤30 at%, 0<c≤20 at%, 0<d ≤25 at%, 0<e≤20 at%, i≥0, 0<j≤5at%, and a+b+c+d+e+i+j=100 at%; and the titanium-based lightweight high-temperature alloy has a simple body-centered cubic structure and dispersed nano-scale precipitates.

[0030] A method for preparing the above-mentioned titanium-based lightweight high-temperature alloy, the method specifically comprises the following steps:

[0031] S1) According to the designed proportion, the atomic percentage of each raw material is converted into the mass ratio of each element, and the ingredients are prepared; each raw material is a metal or non-metal single substance raw material with a purity of ≥ 99.9 wt%;

[0032] S2) placing the raw materials weighed in S1) and the titanium ingot into a copper crucible of a non-consumable vacuum arc furnace in the order of their melting points from low to high, with the volatile elements placed in the lower layer; then evacuating the furnace chamber to remove oxygen;

[0033] The specific process of emptying is: when the low vacuum degree reaches 1.0× 10 0 ~5× 10 0 Pa, close the low vacuum valve; open the high vacuum valve, and draw a high vacuum. When the high vacuum degree reaches 1.0 × 10 -4 ~8 × 10 -4 After the pressure reaches 0.047 MPa, close the high vacuum valve and fill the furnace chamber with high-purity argon gas to 0.047 MPa (allowing a fluctuation of 0.002 MPa), and repeat this process at least twice;

[0034] S3) arc melting is performed under the protection of high-purity argon gas, firstly melting the titanium ingot, then melting and cooling the alloy raw materials of each component to obtain an alloy ingot, and then melting the obtained alloy ingot and drop-casting / casting it into a water-cooled copper mold to finally obtain a titanium-based lightweight high-temperature alloy;

[0035] The specific process of smelting is:

[0036] The melting time of each ingot is at least 2.5 min. After each melting, the alloy ingot is turned over and tilted using a turning rod after the alloy ingot has cooled. This process is repeated for a total of six meltings. After the alloy has been melted three times, the furnace chamber needs to be evacuated again and filled with high-purity argon gas.

[0037] The titanium-based lightweight high-temperature alloy obtained by the preparation method has a density range of 4.88-5.40 g·cm -3 The tensile strength at room temperature is 843-1124 MPa, and the elongation at break is greater than 10%. The tensile strength at 800℃ is 230-697 MPa.

[0038] Phase analysis of a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity of the present invention: The prepared lightweight high-temperature alloy was analyzed by using a Rigaku Smartlab X-ray diffractometer produced by Rigaku Corporation of Japan: a Cu-Kα (λ = 0.1542 nm) ray source was used, the working voltage was 40 kV, and the working current was 200 mA; an electric spark wire cutting machine was used to cut a 10 × 10 × 1.5 mm diameter ingot from the initial master alloy ingot. 3 Before testing, use 240# , 600 # , 1000 # , and 2000 # The surface of the sample to be tested was polished flat and smooth with sandpaper, and then ultrasonic vibration cleaning was performed with anhydrous ethanol. The sample was tested after it was dried. The test angle range was 20 - 90 °, the scanning speed was 10 ° / min, and the measurement angle error was less than 0.02 °;

[0039] Microstructure detection: The Supra55 field emission scanning electron microscope produced by Zeiss, Germany, was used to observe the microstructure of the as-cast lightweight high-temperature alloy. The wire-cut electrospark cutting was used to cut the sample with a size of 10 × 3 × 1.3 mm. 3 The thin slice samples were then # , 600 # , 1000 # and 2000 # The samples were mechanically polished with sandpaper, and finally electrochemically polished with 6% perchloric acid + 34% n-butanol + 60% methanol (volume fraction) electrolyte. The polished samples were placed in deionized water for full dilution to remove the residual electrolyte, and then placed in anhydrous ethanol for ultrasonic vibration cleaning. After the samples were fully dried, they were observed under an electron microscope.

[0040] Room temperature quasi-static tensile mechanical properties test: The room temperature tensile mechanical properties test was carried out using a CMT 4105 electronic universal testing machine with a strain rate of 1 × 10 -3 s -1 ; The sample was processed into a gauge size of 5 × 15 × 1.3 mm using an electric spark wire cutting machine. 3 Tensile tests were performed on dog-bone shaped plate specimens. At least three samples were selected for each alloy composition to ensure the repeatability of the test.

[0041] High temperature quasi-static tensile mechanical properties test: The high temperature tensile mechanical properties test was carried out using a LE 5105 electronic universal testing machine with a strain rate of 6.67 × 10 -3 s -1 ; Use electric spark wire cutting machine to process the sample into a gauge size of 2× 8 × 1 mm 3 Tensile tests were performed on dog-bone shaped plate specimens. At least three samples were selected for each alloy composition to ensure the repeatability of the test.

[0042] Density measurement: The density of the prepared lightweight high-temperature alloy was measured according to the Archimedean principle: First, an electronic balance (with an accuracy of 10 -3g) Weigh the mass m of the sample to be tested in the air, then place a small beaker filled with distilled water on the tray of the electronic balance, and return the reading to zero after the balance reading stabilizes; finally, suspend the sample to be tested in the beaker with a thin wire and completely immerse it in the distilled water without touching the beaker wall and keep it stable and motionless, and record the reading n on the electronic balance at this time, according to the formula:

[0043] ,

[0044] The density of the sample to be tested can be calculated. It should be noted that during the weighing process, it is necessary to ensure that there are no bubbles adhering to the sample surface and the inner wall of the beaker to reduce the measurement deviation. At the same time, in order to further reduce the measurement error, the average value is generally obtained through multiple measurements. Among them, the sample used is the same as the sample used for the scanning electron microscope test.

[0045] The lightweight high-temperature alloy prepared by the method has a simple body-centered cubic structure, with dispersed nanoscale precipitation phases in the matrix, and an alloy density of 4.88-5.40 g·cm -3 The room temperature tensile strength is 843 – 1124 MPa, the elongation at break is greater than 10%, the 800℃ tensile strength is 230 – 697 MPa, and the elongation at break is greater than 4.5%.

[0046] Example 1

[0047] A titanium-based lightweight high-temperature alloy with high tensile strength at room temperature and high temperature, and high tensile plasticity, whose composition (atomic ratio) is: Ti 50 V 14.8 Nb 15 Al 10 Cr5Zr5Si 0.2 The room temperature tensile strength of the alloy is 1116 MPa, the tensile plasticity is 7.5%, the tensile strength at 800℃ is 606 MPa, the tensile plasticity is 47%, and the density is 5.392 g·cm -3 The prepared alloy is mainly composed of BCC phase, and the nanoscale precipitates are evenly distributed in the matrix.

[0048] Example 2

[0049] A titanium-based lightweight high-temperature alloy with high tensile strength and high tensile plasticity at room temperature and high temperature, and its composition (atomic ratio) is: Ti 50 V 14.6 Nb 15 Al 10 Cr5Zr5Si 0.4 The room temperature tensile mechanical properties of the alloy are shown in Figure 1 As shown in Figure 2, the tensile strength of the alloy is 1190 MPa and the elongation at break is 11%. 50 V14.6 Nb 15 Al10 Cr5Zr5Si 0.4 The results of tensile mechanical properties of the alloy at 800℃ are as follows Figure 2 As shown in Figure 2, the tensile strength of the alloy is 697 MPa and the elongation at break is 61%. Figure 3 From the XRD spectrum in the figure, it can be seen that the prepared alloy is mainly composed of BCC phase; Figure 4 The SEM image of the alloy microstructure shows that the white dots are nanoscale precipitates. The density of the alloy is 5.383 g·cm -3 .

[0050] Example 3

[0051] A titanium-based lightweight high-temperature alloy with high tensile strength and high tensile plasticity at room temperature and high temperature, and its composition (atomic ratio) is: Ti 59.6 V8Nb9 13 Cr5Zr5Si 0.4 The room temperature tensile strength of the alloy is 1206 MPa, the tensile plasticity is 12%, the tensile strength at 800℃ is 445 MPa, the tensile plasticity is 73%, and the density is 4.982 g·cm -3 The prepared alloy is mainly composed of BCC phase, and the nanoscale precipitates are evenly distributed in the matrix.

[0052] Example 4

[0053] A titanium-based lightweight high-temperature alloy with high tensile strength and high tensile plasticity at room temperature and high temperature, and its composition (atomic ratio) is: Ti 60 V 10.4 Nb 10 Al 13 Cr5Si 1.6 The room temperature tensile mechanical properties are shown in Figure 1 As shown in Figure 1, the tensile strength of the alloy is 1093 MPa and the elongation at break is 12%. The tensile mechanical properties at 800℃ are shown in Figure 1. Figure 2 As shown, the tensile strength is 352 MPa and the elongation at break is 81%. Figure 3 From the XRD spectrum in the figure, it can be seen that the prepared alloy is mainly composed of BCC phase; Figure 5 The SEM image of the alloy microstructure shows that the white dots are nanoscale precipitates. The density of the alloy is 4.899 g·cm -3 .

[0054] Example 5

[0055] A titanium-based lightweight high-temperature alloy with high tensile strength and high tensile plasticity at room temperature and high temperature, and its composition (atomic ratio) is: Ti 60 V10.2 Nb 10 Al 13 Cr5Si 1.8 The room temperature tensile strength of the alloy is 1116 MPa, the tensile plasticity is 10.5%, the tensile strength at 800℃ is 359 MPa, the tensile plasticity is 88%, and the density is 4.891 g·cm -3 The prepared alloy is mainly composed of BCC phase, and the nanoscale precipitates are evenly distributed in the matrix.

[0056] The above is a detailed introduction to a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity, as well as its preparation and application provided in 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 method and scope of application. In summary, the content of this specification should not be understood as a limitation on the present application.

[0057] If certain words are used in the specification and claims to refer to specific components, those skilled in the art should understand that hardware manufacturers may use different nouns to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. As mentioned in the entire specification and claims, "including" and "comprising" are open-ended terms, so they should be interpreted as "including / including but not limited to". "Approximately" means that within an acceptable error range, 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 a preferred embodiment of the present application, but the description is for the purpose of illustrating the general principles of the present application, and is not used to limit the scope of the present application. The scope of protection of the present application shall be subject to that defined in the attached claims.

[0058] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0059] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0060] The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall be within the scope of protection of the present application if they do not deviate from the spirit and scope of the present application.

Claims

1. A method for preparing a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity, characterized in that: The chemical formula of the titanium-based lightweight high-temperature alloy is Ti 50 V 14.8 Nb 15 Al 10 Cr5Zr5Si 0.2 The room temperature tensile strength of the alloy is 1116 MPa, the tensile plasticity is 7.5%, the tensile strength at 800℃ is 606 MPa, the tensile plasticity is 47%, and the density is 5.392 g·cm -3 ; The prepared alloy is mainly composed of BCC phase, and the nanoscale precipitation phase is evenly distributed in the matrix; The method specifically comprises the following steps: S1) According to the designed proportion, the atomic percentage of each raw material is converted into the mass ratio of each element and the ingredients are prepared; S2) Put the weighed raw materials in S1) and the titanium ingot into the copper crucible of the non-consumable vacuum arc furnace in the order of their melting points from low to high, with the volatile elements placed in the lower layer; then evacuate the furnace chamber to remove oxygen; when the low vacuum degree reaches 1.0 10 0 -5.0 × 10 0 Pa, close the low vacuum valve; open the high vacuum valve, and draw a high vacuum. When the high vacuum degree reaches 1.0 × 10 -4 -8.0 × 10 -4 After Pa, close the high vacuum valve and fill the furnace chamber with high-purity argon gas to 0.047 MPa±0.002 MPa, and repeat this process at least twice; S3) Arc melting is carried out under the protection of high-purity argon gas. First, the titanium ingot is melted, and then the alloy raw materials of each component are melted and cooled to obtain an alloy ingot. After the obtained alloy ingot is melted, it is drop-cast or cast into a water-cooled copper mold to finally obtain a titanium-based lightweight high-temperature alloy.

2. A method for preparing a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity, characterized in that: The chemical formula of the titanium-based lightweight high-temperature alloy is Ti 50 V 14.6 Nb 15 Al 10 Cr5Zr5Si 0.4 The room temperature tensile strength of the alloy is 1190 MPa, the tensile plasticity is 11%, the tensile strength at 800℃ is 697 MPa, the tensile plasticity is 61%, and the density is 5.383 g·cm -3 ; The prepared alloy is mainly composed of BCC phase, and the nanoscale precipitation phase is evenly distributed in the matrix; The method specifically comprises the following steps: S1) According to the designed proportion, the atomic percentage of each raw material is converted into the mass ratio of each element and the ingredients are prepared; S2) Put the weighed raw materials in S1) and the titanium ingot into the copper crucible of the non-consumable vacuum arc furnace in the order of their melting points from low to high, with the volatile elements placed in the lower layer; then evacuate the furnace chamber to remove oxygen; when the low vacuum degree reaches 1.0 10 0 -5.0 × 10 0 Pa, close the low vacuum valve; open the high vacuum valve, and draw a high vacuum. When the high vacuum degree reaches 1.0 × 10 -4 -8.0 × 10 -4 After Pa, close the high vacuum valve and fill the furnace chamber with high-purity argon gas to 0.047 MPa±0.002 MPa, and repeat this process at least twice; S3) Arc melting is carried out under the protection of high-purity argon gas. First, the titanium ingot is melted, and then the alloy raw materials of each component are melted and cooled to obtain an alloy ingot. After the obtained alloy ingot is melted, it is drop-cast or cast into a water-cooled copper mold to finally obtain a titanium-based lightweight high-temperature alloy.

3. A method for preparing a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity, characterized in that: The chemical formula of the titanium-based lightweight high-temperature alloy is Ti 59.6 V8Nb9 13 Cr5Zr5Si 0.4 The room temperature tensile strength of the alloy is 1206 MPa, the tensile plasticity is 12%, the tensile strength at 800℃ is 445 MPa, the tensile plasticity is 73%, and the density is 4.982 g·cm -3 ; The prepared alloy is mainly composed of BCC phase, and the nanoscale precipitation phase is evenly distributed in the matrix; The method specifically comprises the following steps: S1) According to the designed proportion, the atomic percentage of each raw material is converted into the mass ratio of each element and the ingredients are prepared; S2) Put the weighed raw materials in S1) and the titanium ingot into the copper crucible of the non-consumable vacuum arc furnace in the order of their melting points from low to high, with the volatile elements placed in the lower layer; then evacuate the furnace chamber to remove oxygen; when the low vacuum degree reaches 1.0 10 0 -5.0 × 10 0 Pa, close the low vacuum valve; open the high vacuum valve, and draw a high vacuum. When the high vacuum degree reaches 1.0 × 10 -4 -8.0 × 10 -4 After Pa, close the high vacuum valve and fill the furnace chamber with high-purity argon gas to 0.047 MPa±0.002 MPa, and repeat this process at least twice; S3) Arc melting is carried out under the protection of high-purity argon gas. First, the titanium ingot is melted, and then the alloy raw materials of each component are melted and cooled to obtain an alloy ingot. After the obtained alloy ingot is melted, it is drop-cast or cast into a water-cooled copper mold to finally obtain a titanium-based lightweight high-temperature alloy.

4. A method for preparing a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity, wherein the titanium-based lightweight high-temperature alloy has a chemical formula of Ti 60 V 10.4 Nb 10 Al 13 Cr5Si 1.6 The room temperature tensile strength of the alloy is 1093 MPa, the tensile plasticity is 12%, the tensile strength at 800℃ is 352 MPa, the tensile plasticity is 81%, and the density is 4.899 g·cm -3 The prepared alloy is mainly composed of a BCC phase, and the nanoscale precipitated phase is uniformly distributed in the matrix. The method specifically comprises the following steps: S1) According to the designed proportion, the atomic percentage of each raw material is converted into the mass ratio of each element and the ingredients are prepared; S2) Put the weighed raw materials in S1) and the titanium ingot into the copper crucible of the non-consumable vacuum arc furnace in the order of their melting points from low to high, with the volatile elements placed in the lower layer; then evacuate the furnace chamber to remove oxygen; when the low vacuum degree reaches 1.0 10 0 -5.0 × 10 0 Pa, close the low vacuum valve; open the high vacuum valve, and draw a high vacuum. When the high vacuum degree reaches 1.0 × 10 -4 -8.0 × 10 -4 After Pa, close the high vacuum valve and fill the furnace chamber with high-purity argon gas to 0.047 MPa±0.002 MPa, and repeat this process at least twice; S3) Arc melting is carried out under the protection of high-purity argon gas. First, the titanium ingot is melted, and then the alloy raw materials of each component are melted and cooled to obtain an alloy ingot. After the obtained alloy ingot is melted, it is drop-cast or cast into a water-cooled copper mold to finally obtain a titanium-based lightweight high-temperature alloy.

5. A method for preparing a titanium-based lightweight high-temperature alloy with high strength and high tensile plasticity, characterized in that: The chemical formula of the titanium-based lightweight high-temperature alloy is Ti 60 V 10.2 Nb 10 Al 13 Cr5Si 1.8 The room temperature tensile strength of the alloy is 1116 MPa, the tensile plasticity is 10.5%, the tensile strength at 800℃ is 359 MPa, the tensile plasticity is 88%, and the density is 4.891 g·cm -3 The prepared alloy is mainly composed of BCC phase, and the nanoscale precipitation phase is evenly distributed in the matrix. The method specifically comprises the following steps: S1) According to the designed proportion, the atomic percentage of each raw material is converted into the mass ratio of each element and the ingredients are prepared; S2) Put the weighed raw materials in S1) and the titanium ingot into the copper crucible of the non-consumable vacuum arc furnace in the order of their melting points from low to high, with the volatile elements placed in the lower layer; then evacuate the furnace chamber to remove oxygen; when the low vacuum degree reaches 1.0 10 0 -5.0 × 10 0 Pa, close the low vacuum valve; open the high vacuum valve, and draw a high vacuum. When the high vacuum degree reaches 1.0 × 10 -4 -8.0 × 10 -4 After Pa, close the high vacuum valve and fill the furnace chamber with high-purity argon gas to 0.047 MPa±0.002 MPa, and repeat this process at least twice; S3) Arc melting is carried out under the protection of high-purity argon gas. First, the titanium ingot is melted, and then the alloy raw materials of each component are melted and cooled to obtain an alloy ingot. After the obtained alloy ingot is melted, it is drop-cast or cast into a water-cooled copper mold to finally obtain a titanium-based lightweight high-temperature alloy.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The titanium-based lightweight high-temperature alloy obtained by the preparation method has a density range of 4.88-5.40 g·cm -3 The tensile strength at room temperature is 843-1124 MPa, the elongation at break is greater than 10%, and the tensile strength at 800°C is 230-697 MPa.

7. A titanium-based lightweight high-temperature alloy prepared by the preparation method according to any one of claims 1 to 5 is used in the fields of energy, transportation and aerospace.

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