Method for producing tantalum-aluminum alloys

Abstract

The preparation method of the tantalum-aluminum alloy disclosed by the embodiment of the present application comprises the following steps: S1, mixing tantalum oxide, metal aluminum and metal magnesium in an oxygen-free environment to obtain mixed raw materials; S2, heating the mixed raw materials to a reaction temperature to cause a self-sustaining reaction; wherein, the metal magnesium in the mixed raw materials reduces the tantalum oxide to generate metal tantalum and magnesium oxide, and the generated metal tantalum forms a tantalum-aluminum alloy with the metal aluminum in the mixed raw materials; S3, removing the magnesium oxide to obtain a tantalum-aluminum alloy powder. The metal magnesium reacts with the tantalum oxide to generate metal tantalum, the generated metal tantalum directly forms a tantalum-aluminum alloy with the raw material metal aluminum, and then the acid solution is used to remove the magnesium oxide to obtain the tantalum-aluminum alloy powder; the tantalum and aluminum in the obtained tantalum-aluminum alloy powder are uniformly distributed, and the oxygen content is low; different compositions of the tantalum-aluminum alloy can be prepared according to the composition ratio of the tantalum-aluminum alloy, the method is simple and easy to operate, and has a good application prospect in the field of tantalum-aluminum alloy preparation.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of alloy preparation, and particularly relates to a preparation method of tantalum-aluminum alloy. BACKGROUND

[0002] The tantalum-aluminum alloy has the characteristics of high melting point, oxidation resistance, creep resistance, high specific strength, high hardness, corrosion resistance, etc., and has important application value in key fields such as aerospace, electronic information, medical treatment, etc. As a potential high-temperature metal functional material, the tantalum-aluminum alloy is an ideal material for making attenuators and is often used in electronic components. The tantalum-aluminum alloy is often used as an additive of high-temperature titanium alloy due to the similar melting point with titanium. The element tantalum can strengthen the multi-element composite solid solution effect in the high-temperature titanium alloy, effectively inhibit the composition segregation of the high-temperature titanium alloy, improve the high-temperature strength and temperature resistance of the titanium alloy, and improve the performance of the titanium alloy.

[0003] At present, the common preparation methods of the tantalum-aluminum alloy include the aluminum thermal self-propagating high-temperature synthesis method, the powder metallurgy method, and the induction melting method. In the self-propagating high-temperature synthesis method, a heating agent is added, and after the aluminum thermal reaction is initiated by igniting the heating agent, the reaction can be spontaneously carried out. While the aluminum reduces the tantalum oxide to form tantalum, a large amount of heat is generated. Excessive aluminum and the product tantalum form the tantalum-aluminum alloy under high-temperature conditions. The generated aluminum oxide and the slag former combine to form a molten slag. The tantalum-aluminum alloy with a specific composition is obtained by slag-gold separation. However, the by-product aluminum oxide needs to be removed by adding a slag former. The reaction temperature and the proportion of the molten slag are difficult to control. The aluminum thermal reduction releases a large amount of heat, resulting in a large amount of aluminum volatilization. The composition of the product is difficult to control, and the uniformity of the product is poor. A commonly used strong oxidizing agent, potassium chlorate, is used as the heating agent, which is prone to combustion and explosion, and the process has high risk. In the induction melting method, the aluminum is melted into aluminum liquid by using induction melting, and then tantalum particles are added to the aluminum liquid to prepare the tantalum-aluminum alloy. The tantalum mainly forms the tantalum-aluminum alloy in the form of atomic diffusion with the aluminum. However, the atmosphere requirement of this method is extremely high, otherwise aluminum oxide inclusions are easily formed under high temperature. The content of tantalum in the tantalum-aluminum alloy is low, and the alloy composition is not uniform.

[0004] In summary, due to the large difference in physical properties such as density and melting point between tantalum and aluminum, the existing technology prepared tantalum-aluminum alloy has problems such as high impurity content, composition segregation, and poor uniformity of the structure. SUMMARY

[0005] Therefore, the embodiments of the present application disclose a preparation method of tantalum-aluminum alloy. Without adding a heating agent and a slag former, the characteristics of the generated magnesium oxide being more easily removed than aluminum oxide are directly used. Excessive magnesium is used to reduce the tantalum oxide to prepare the tantalum-aluminum alloy.

[0006] Some embodiments disclose a preparation method of tantalum-aluminum alloy, including the following steps:

[0007] S1, the tantalum oxide, metal aluminum and metal magnesium are mixed in an oxygen-free environment to obtain mixed raw materials;

[0008] S2, the mixed raw materials are heated to a reaction temperature to cause a self-propagating reaction; wherein the metal magnesium in the mixed raw materials reduces the tantalum oxide to generate metal tantalum and magnesium oxide, and the generated metal tantalum forms a tantalum-aluminum alloy with the metal aluminum in the mixed raw materials;

[0009] S3, the magnesium oxide is removed to obtain a tantalum-aluminum alloy powder.

[0010] Further, some embodiments disclose a preparation method of a tantalum-aluminum alloy, wherein the molar ratio of the metal magnesium to the tantalum oxide in the mixed raw materials is not less than 5, and the ratio of the metal aluminum to the tantalum oxide is determined according to the stoichiometric ratio of the product tantalum-aluminum alloy.

[0011] Some embodiments disclose a preparation method of a tantalum-aluminum alloy, wherein the reaction temperature for generating the tantalum-aluminum alloy in the self-propagating reaction is set to 800-1500℃.

[0012] Some embodiments disclose a preparation method of a tantalum-aluminum alloy, wherein the magnesium oxide is removed by using an acidic solution for washing; the acidic solution includes any combination of hydrochloric acid, sulfuric acid, nitric acid or hydrofluoric acid.

[0013] Some embodiments disclose a preparation method of a tantalum-aluminum alloy, wherein the method for removing the magnesium oxide includes: after washing with the acidic solution, dissolving with distilled water, standing and precipitating, and drying to obtain a tantalum-aluminum alloy powder.

[0014] Some embodiments disclose a preparation method of a tantalum-aluminum alloy, wherein the oxygen-free environment is an inert gas atmosphere.

[0015] Some embodiments disclose a preparation method of a tantalum-aluminum alloy, wherein the inert gas atmosphere is argon.

[0016] Some embodiments disclose a preparation method of a tantalum-aluminum alloy, wherein step S1 further includes molding the mixed raw materials to obtain a raw material blank.

[0017] The preparation method of the tantalum-aluminum alloy disclosed in the embodiments of the present application uses the reaction of the metal magnesium and the tantalum oxide to generate metal tantalum, the generated metal tantalum directly forms a tantalum-aluminum alloy with the raw material metal aluminum, and then the acidic solution is used to remove the magnesium oxide to obtain a tantalum-aluminum alloy powder; no heating agent or slagging agent is used, the obtained tantalum-aluminum alloy is a powder, the tantalum and aluminum are uniformly distributed in the tantalum-aluminum alloy powder, and the oxygen content is low; different compositions of the tantalum-aluminum alloy can be prepared according to the composition ratio of the tantalum-aluminum alloy, the method is simple and easy to operate, and has a good application prospect in the field of tantalum-aluminum alloy preparation. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 SEM-EDS diagram of the tantalum-aluminum alloy in Example 1;

[0019] Figure 2 Example 1 Ta-Al alloy XRD pattern;

[0020] Figure 3 Example 2 Ta-Al alloy SEM-EDS pattern;

[0021] Figure 4 Example 2 Ta-Al alloy XRD pattern. DETAILED DESCRIPTION

[0022] The term "example" is used herein to mean "serving as an example, instance, or illustration," and not to imply or create any preference or requirement for a particular embodiment. Unless otherwise indicated, performance metrics for embodiments of the present application are determined using conventional test methods in the art. It is understood that the terms used herein are not intended to limit the scope of the embodiments of the present application disclosed.

[0023] Unless otherwise indicated, the technical and scientific terms used herein have the same meaning as those commonly understood by one of ordinary skill in the art to which the embodiments of the present application belong; and the experimental methods and techniques used herein are those generally used and accepted in the art, unless otherwise indicated.

[0024] The terms "substantially" and "approximately," as used herein, are used to describe a small fluctuation. For example, they can mean less than or equal to ± 5%, such as less than or equal to ± 2%, such as less than or equal to ± 1%, such as less than or equal to ± 0.5%, such as less than or equal to ± 0.2%, such as less than or equal to ± 0.1%, such as less than or equal to ± 0.05%. Numerical data may, in the various examples herein, be presented in a range format. It is to be understood that such a range format is used only for convenience and brevity and should be understood as a shorthand method of describing individual values of the range. Unless otherwise indicated, a range format is used herein to describe a range including all values therein and including individual values within the indicated range. For example, a range of "1 to 5" should be interpreted to include not only the individual values of 1 and 5, but also the intermediate values of 2, 3, 4, and 5, as well as the individual values of 1, 2, 3, 4, and 5. The same applies to ranges having endpoints that are not absolute values, such as a range of "about 1 to about 5." In this example, the values of 1 and 5 are not absolute values, as the term "about" means a value that is acceptable within manufacturing tolerances. Thus, the range of "about 1 to about 5" includes individual values of 1, 2, 3, 4, and 5, as well as the intermediate values of 1.5, 2.5, 3.5, and 4.5. The same applies to ranges having endpoints that are not absolute values, such as a range of "about 1 to about 5." In this example, the values of 1 and 5 are not absolute values, as the term "about" means a value that is acceptable within manufacturing tolerances. Thus, the range of "about 1 to about 5" includes individual values of 1, 2, 3, 4, and 5, as well as the intermediate values of 1.5, 2.5, 3.5, and 4.5.

[0025] In this document, including the claims, the conjunctions, such as "comprise", "include", "have", "with", "contain", "involve", "hold", and the like, are to be interpreted as open-ended, i.e. as meaning "including but not limited to". Only the conjunctions "consist of" and "consist only of" are closed conjunctions.

[0026] For a better understanding of the present application, numerous specific details are given in the following embodiments. It will be understood by those skilled in the art that the present application can be practiced without certain specific details. In the embodiments, some methods, means, instruments, devices, etc. well known to those skilled in the art are not described in detail in order to highlight the principles of the present application.

[0027] The technical features disclosed in the embodiments of the present application can be combined arbitrarily without conflict, and the resulting technical solutions belong to the disclosure of the present application.

[0028] In some embodiments, the method for preparing the tantalum-aluminum alloy disclosed by some embodiments comprises the steps of:

[0029] S1, mixing the tantalum oxide, the metal aluminum and the metal magnesium in an oxygen-free environment to obtain a mixed raw material; generally, in the mixed raw material, the molar ratio of the metal magnesium to the tantalum oxide is not less than 5, and the ratio of the metal aluminum to the tantalum oxide is determined according to the stoichiometric ratio of the product tantalum-aluminum alloy;

[0030] Generally, the ratio of the metal aluminum to the metal tantalum in the obtained product tantalum-aluminum alloy is equal to the ratio of the metal aluminum to the tantalum oxide in the mixed raw material; generally, the oxygen-free environment is an inert atmosphere environment.

[0031] In some embodiments, the inert atmosphere is argon.

[0032] S2, heating the mixed raw material to a reaction temperature to cause a self-propagating reaction; wherein the metal magnesium in the mixed raw material reduces the tantalum oxide to generate the metal tantalum and the magnesium oxide, and the metal tantalum forms the tantalum-aluminum alloy with the metal aluminum in the mixed raw material; in some embodiments, the reaction temperature for generating the tantalum-aluminum alloy in the self-propagating reaction is set to 800-1500℃; generally, the generated product is composed of the tantalum-aluminum alloy and the magnesium oxide;

[0033] S3, removing the magnesium oxide to obtain the tantalum-aluminum alloy powder; in some embodiments, the acid solution washing method is used to remove the magnesium oxide; the acid solution includes any combination of hydrochloric acid, sulfuric acid, nitric acid or hydrofluoric acid; generally, the product is washed with the acid solution to dissolve the magnesium oxide, the obtained solution is left to precipitate, then the supernatant is removed to leave the tantalum-aluminum alloy powder, the tantalum-aluminum alloy powder is further washed with distilled water, and the tantalum-aluminum alloy powder target product is obtained after drying;

[0034] Some embodiments disclose a method for preparing a tantalum-aluminum alloy, step S1 further comprises: molding the mixed raw materials into a raw material blank; heating the obtained raw material blank to a reaction temperature to perform a self-propagating reaction; wherein the metallic magnesium in the raw material blank reduces the tantalum oxide to form metallic tantalum and magnesium oxide, and the formed metallic tantalum forms a tantalum-aluminum alloy with the metallic aluminum in the raw material blank; the raw material blank is converted into a product blank composed of the tantalum-aluminum alloy and the magnesium oxide, and then the product blank is washed with an acid washing solution to dissolve the magnesium oxide; after standing and precipitation, the supernatant is removed to leave the tantalum-aluminum alloy powder, the tantalum-aluminum alloy powder is washed with distilled water, and further drying obtains the tantalum-aluminum alloy powder.

[0035] The technical details are further exemplarily described below in conjunction with embodiments.

[0036] Embodiment 1

[0037] In embodiment 1, the method for preparing a tantalum-aluminum alloy comprises:

[0038] According to a molar ratio of 1:6:10, the tantalum pentoxide, the metallic aluminum and the metallic magnesium are weighed and placed in a mixing tank to mix uniformly to obtain a raw material mixture;

[0039] The raw material mixture is pre-pressed into a cylindrical mold with a diameter of 12.5 mm, and the pressed blank is pre-pressed on a tablet press under the condition of 100 MPa to obtain a raw material blank;

[0040] The raw material blank is placed in a reaction furnace, the reaction furnace is heated to a reaction temperature of 1000℃ to initiate a self-propagating reaction, and the reaction temperature is kept for 1h to obtain a reaction product;

[0041] After the temperature in the reaction furnace decreases to room temperature, the self-propagating reaction product is dissolved with hydrochloric acid and then left to stand and precipitate, the supernatant is removed, and the product is dissolved with distilled water and then left to stand and precipitate, which is repeated three times, and the product is freeze-dried to obtain a tantalum-aluminum alloy powder.

[0042] Figure 1 The SEM-EDS diagram of the tantalum-aluminum alloy obtained in embodiment 1 is as follows: Figure 2 The XRD diagram of the tantalum-aluminum alloy is as follows: Figure 1 It can be seen that the tantalum and aluminum are uniformly distributed in the tantalum-aluminum alloy, and the distribution positions are consistent, forming the tantalum-aluminum alloy; and Figure 2 It can be seen that the product obtained in embodiment 1 is a tantalum-aluminum alloy powder with uniform distribution of tantalum and aluminum, and the oxygen content of the powder is measured to be 0.12%.

[0043] Embodiment 2

[0044] In embodiment 2, the method for preparing a tantalum-aluminum alloy comprises:

[0045] According to a molar ratio of 1:6:10, the tantalum pentoxide, the metallic aluminum and the metallic magnesium are weighed and placed in a mixing tank to mix uniformly to obtain a raw material mixture;

[0046] The raw material mixture is placed in a reaction furnace, the reaction furnace is heated to a reaction temperature of 1000 DEG C, a self-propagating reaction is initiated, and the reaction temperature is maintained for 1 h; a reaction product is obtained;

[0047] The temperature in the reaction furnace is reduced to room temperature, the self-propagating reaction product is dissolved with hydrochloric acid and then allowed to stand and precipitate, the supernatant is removed, and the product is dissolved with distilled water and then allowed to stand and precipitate, the operation is repeated three times, and the product is freeze-dried to obtain a tantalum-aluminum alloy powder.

[0048] Figure 3 The SEM-EDS diagram of the tantalum-aluminum alloy obtained in Example 2 is shown in Figure 1. Figure 4 The XRD diagram of the tantalum-aluminum alloy is shown in Figure 2. Figure 3 It can be seen that the tantalum atoms and the aluminum atoms are uniformly distributed in the tantalum-aluminum alloy, and the distribution positions are consistent, and the tantalum-aluminum alloy is formed. Figure 4 It can be seen that the product obtained in Example 2 is a tantalum-aluminum alloy powder with uniform distribution of tantalum and aluminum, and the oxygen content of the powder is 0.38%.

[0049] The preparation method of the tantalum-aluminum alloy disclosed in the embodiments of the present application utilizes the reaction of magnesium and tantalum oxide to generate metallic tantalum, the generated metallic tantalum directly forms a tantalum-aluminum alloy with raw material aluminum, and then the magnesium oxide is removed by using an acid solution to obtain a tantalum-aluminum alloy powder; no heating agent or slagging agent is used, the obtained tantalum-aluminum alloy is in the form of powder, the tantalum and aluminum are uniformly distributed in the tantalum-aluminum alloy powder, and the oxygen content is low; different compositions of the tantalum-aluminum alloy can be prepared according to the composition ratio of the tantalum-aluminum alloy, the method is simple and easy to operate, and has a good application prospect in the field of tantalum-aluminum alloy preparation.

[0050] The technical solutions disclosed in the embodiments of the present application and the technical details disclosed in the embodiments are only exemplary to illustrate the inventive concept of the present application, and do not constitute a limitation on the technical solutions of the embodiments of the present application, and any conventional changes, substitutions or combinations of the technical details disclosed in the embodiments of the present application all have the same inventive concept as the present application, and are within the protection scope of the claims of the present application.

Claims

1. A method for producing a tantalum-aluminum alloy, characterized by, The method comprises the steps of: S1, mixing tantalum oxide, metal aluminum and metal magnesium in an oxygen-free environment to obtain a mixed raw material; in the mixed raw material, the molar ratio of metal magnesium to tantalum oxide is not less than 5, and the ratio of metal aluminum to tantalum oxide is determined according to the stoichiometric ratio of the product tantalum-aluminum alloy; S2, heating the mixed raw material to a reaction temperature to cause a self-propagating reaction; wherein the reaction temperature is set to 800-1500 DEG C, the metal magnesium in the mixed raw material reduces the tantalum oxide to generate metal tantalum and magnesium oxide, and the generated metal tantalum forms a tantalum-aluminum alloy with the metal aluminum in the mixed raw material; S3, removing the magnesium oxide to obtain a tantalum-aluminum alloy powder.

2. The method of producing a tantalum-aluminum alloy according to claim 1, characterized by, The method for removing the magnesium oxide includes: after washing with an acidic solution, dissolving with distilled water, standing and precipitating, and drying to obtain a tantalum-aluminum alloy powder.

3. The method of producing a tantalum-aluminum alloy according to claim 2, characterized by, The oxygen-free environment is an inert gas atmosphere.

4. The method of producing a tantalum-aluminum alloy according to claim 1, characterized by, The inert gas is argon.

5. The method of producing a tantalum-aluminum alloy according to claim 4, characterized by, Step S1 further comprises molding the mixed raw material to obtain a raw material blank.

6. The method of producing a tantalum-aluminum alloy according to claim 1, characterized by, ​

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