A corrosion-resistant alloy material and a method for manufacturing the same

Abstract

The application discloses an anti-corrosion alloy material and a preparation method thereof, and relates to the technical field of alloy materials. The alloy material is prepared by sintering an alloy powder obtained by ball-milling and blending of an aluminum-based alloy powder and a graphene / aluminum-based alloy composite powder, and is loaded into a mold; the mass ratio of the aluminum-based alloy powder and the graphene / aluminum-based alloy composite powder is (8-9):(1-2); the aluminum-based alloy powder is obtained by atomization of an aluminum-based alloy bar through a vacuum induction gas atomization technology; the graphene / aluminum-based alloy composite powder is prepared by modification of aluminum-based alloy powder by graphene; the graphene is at least one of graphene oxide and a modified material of graphene oxide; and the modified material of graphene oxide is nitrogen-doped graphene oxide, boron-doped graphene oxide or nitrogen-boron co-doped graphene oxide.

Description

Technical Field

[0001] This invention relates to the field of alloy materials technology, specifically to a corrosion-resistant alloy material and its preparation method. Background Technology

[0002] In recent years, driven by the "dual-carbon" strategic goals, new energy vehicles have rapidly emerged, thus promoting the development of lightweight vehicles. Aluminum-based alloy materials are highly compatible with the requirements for lightweight automotive materials. With its core advantages of low density and high specific strength, aluminum-based alloys can significantly reduce the overall weight of new energy vehicles, thereby reducing energy consumption and helping new energy vehicles achieve the dual goals of reduced driving range and carbon emissions.

[0003] However, new energy vehicles operate in complex environments, and their body, chassis, and other components are frequently exposed to rain and other forms of corrosion, posing a significant potential safety hazard at all times. Therefore, current new energy vehicle production imposes more stringent requirements on the corrosion resistance of aluminum-based alloy materials. Furthermore, the components of new energy vehicles also require excellent mechanical properties.

[0004] Based on this, the present invention provides a corrosion-resistant alloy material and its preparation method, which enhances the corrosion resistance of existing aluminum-based alloys while strengthening their mechanical properties, so that the alloy material can adapt to more severe working conditions, which is of great significance. Summary of the Invention

[0005] The purpose of this invention is to provide a corrosion-resistant alloy material and its preparation method to solve the problems mentioned in the background art.

[0006] To achieve the above-mentioned objectives, the first aspect of this invention provides the following technical solution: A method for preparing a corrosion-resistant alloy material involves loading alloy powder obtained by ball milling and blending aluminum-based alloy powder and graphene / aluminum-based alloy composite powder into a mold and then sintering it.

[0007] Furthermore, the mass ratio of the aluminum-based alloy powder to the graphene / aluminum-based alloy composite powder is (8~9):(1~2).

[0008] This ratio ensures that graphene is uniformly dispersed in the aluminum alloy matrix, enhancing the corrosion resistance of the aluminum alloy while preventing a decrease in its toughness.

[0009] Furthermore, the aluminum-based alloy powder is obtained by atomizing aluminum-based alloy rods using vacuum induction gas atomization technology.

[0010] Furthermore, the vacuum induction gas atomization technology includes the following process parameters: The melting parameters are as follows: the protective gas is argon, the melting temperature is 710~740℃, and the holding time is 10~20min; The atomization parameters are: melt flow rate of 20~25g / s, atomizing gas of argon, and atomization pressure of 3~5MPa.

[0011] Further, the preparation method of the graphene / aluminum-based alloy composite powder is as follows: (1) Add cationic surfactant to deionized water and ultrasonically disperse for 10-30 min to obtain a cationic surfactant solution of 0.1-0.5 g / L; add aluminum-based alloy powder to the cationic surfactant solution and ultrasonically disperse for 20-60 min, then filter, wash and dry to obtain modified aluminum-based alloy powder; (2) Add graphene to deionized water and ultrasonically disperse for 10-30 min to obtain a graphene suspension of 1-2 g / L; add modified aluminum-based alloy powder to the graphene suspension and stir and mix at 50-60℃ for 20-60 min, then add ascorbic acid and stir and mix for 1-2 h, then filter, wash and vacuum dry to obtain a preliminary reduced composite powder; (3) Under a hydrogen atmosphere, heat the preliminary reduced composite powder to 300-400℃ and keep it at 1-2 h to obtain graphene / aluminum-based alloy composite powder.

[0012] This invention first uses a cationic surfactant to modify the surface of aluminum-based alloy powder to obtain positively charged modified aluminum-based alloy powder, which facilitates electrostatic adsorption with graphene oxide and graphene oxide-modified materials to form composite powder, greatly promoting the dispersion of graphene; subsequently, through reduction treatment, a graphene / aluminum-based alloy composite powder with tight interfacial bonding is prepared.

[0013] Furthermore, the amount of the cationic surfactant used is 1 to 2 wt% of the mass of the aluminum-based alloy powder.

[0014] Furthermore, the cationic surfactant includes, but is not limited to, at least one of dodecyltrimethylammonium bromide, hexadecyltrimethylammonium bromide, and octadecyltrimethylammonium chloride.

[0015] Furthermore, the mass ratio of the graphene to the modified aluminum-based alloy powder is (1~3):100.

[0016] Furthermore, the amount of ascorbic acid used is 1.2 to 2 times the mass of graphene.

[0017] Furthermore, the graphene is at least one of graphene oxide and modified graphene oxide; wherein the modified graphene oxide is nitrogen-doped graphene oxide, boron-doped graphene oxide, or nitrogen-boron co-doped graphene oxide.

[0018] Furthermore, the graphene is obtained by mixing and compounding graphene oxide and nitrogen-boron co-doped graphene oxide in a mass ratio of 1:(3~4).

[0019] Further, the preparation method of the nitrogen-doped graphene oxide, boron-doped graphene oxide, or nitrogen-boron co-doped graphene oxide is as follows: (1) Add graphene oxide to deionized water and ultrasonically disperse for 10-30 min to obtain a graphene oxide suspension of 0.6-2 g / L; (2) Add a nitrogen source or a boron source or a nitrogen source and a boron source to the graphene oxide suspension, ultrasonically disperse for 10-30 min, freeze dry, and obtain nitrogen-doped graphene oxide, boron-doped graphene oxide, or nitrogen-boron co-doped graphene oxide.

[0020] Furthermore, if nitrogen-doped graphene oxide is prepared, the mass ratio of graphene oxide to nitrogen source is 1:(1~5); if boron-doped graphene oxide is prepared, the mass ratio of graphene oxide to boron source is 1:(1~5); if nitrogen-boron co-doped graphene oxide is prepared, the mass ratio of graphene oxide, nitrogen source, and boron source is 1:(0.5~2.5):(0.5~2.5).

[0021] Furthermore, the nitrogen source is urea.

[0022] Furthermore, the boron source is boric acid.

[0023] Furthermore, the parameters for ball milling and blending are as follows: tungsten carbide balls with a diameter of 8-10 mm are used as grinding balls, the ball milling speed is 60-100 r / min, and the ball milling time is 20-40 min.

[0024] Furthermore, the sintering is spark plasma sintering, and the sintering process is as follows: the mold containing alloy powder is placed in a spark plasma sintering furnace, and under vacuum conditions, it is pressurized at a rate of 1~3 MPa / min until the pressure reaches 40~50 MPa. After pressurization, the temperature is increased to 400~500℃ at a rate of 50~80℃ / min and held for 5~10 min. Then, the pressure is increased to 60~70 MPa at a rate of 1~3 MPa / min, and the temperature is increased to 580~590℃ at a rate of 20~30℃ / min and held for 5~10 min. Finally, when the furnace cools to 100±5℃, the furnace is unloaded, and then cooled to room temperature before being removed.

[0025] A second aspect of the present invention provides a corrosion-resistant alloy material prepared by the above-described preparation method.

[0026] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention uses graphene / aluminum-based alloy composite powder to reinforce the aluminum-based alloy matrix; by introducing graphene into the graphene / aluminum-based alloy composite powder, the interfacial compatibility between graphene and the aluminum-based alloy matrix is ​​greatly improved, which has a significant effect on enhancing the corrosion resistance of the aluminum alloy.

[0027] 2. The present invention further employs nitrogen-doped graphene oxide, boron-doped graphene oxide, and nitrogen-boron co-doped graphene oxide to modify aluminum-based alloy powder. By doping with nitrogen and boron, the surface wettability of graphene is improved and the interfacial reaction is suppressed, thereby improving the interfacial compatibility between graphene and the aluminum-based alloy matrix. At the same time, it can also promote a more compact internal structure of the alloy in the subsequent process, thereby better blocking the penetration and diffusion of corrosive media and greatly improving the mechanical properties and corrosion resistance of aluminum alloy.

[0028] 3. The present invention further modifies aluminum-based alloy powder by combining graphene oxide and nitrogen-boron co-doped graphene, which can improve the tensile strength and corrosion resistance of aluminum alloys, and balance the toughness decay of aluminum alloys, thereby obtaining aluminum alloy materials with better comprehensive performance.

[0029] 4. This invention further ensures the comprehensive performance of aluminum alloys by controlling the mass ratio of graphene / aluminum alloy composite powder and aluminum-based alloy powder.

[0030] In summary, the preparation process of this invention is simple, highly controllable, and moderately cost-effective. It comprehensively prepares aluminum alloy materials with high density and high corrosion resistance, which exhibit excellent mechanical properties and corrosion resistance, and can adapt to more severe working environments, which is of great significance. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention are described in detail and completely below. It should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other equivalent embodiments obtained by those skilled in the art based on the embodiments disclosed in this invention without creative effort are within the protection scope of this invention.

[0032] It should be noted that there are no special restrictions on the suppliers of the raw materials involved in this invention; exemplarily, they include: 6061 series aluminum alloy bars, grade T6, purchased from Suzhou Yongxunchang Metal Materials Co., Ltd. Hexadecyltrimethylammonium bromide; ascorbic acid; graphene oxide with sheets <10μm and thickness of 0.8~1.2nm; urea; boric acid, all commercially available.

[0033] The corrosion-resistant aluminum alloy material prepared by this invention has dimensions of 60mm in length × 6mm in width × 3mm in thickness.

[0034] Preliminary preparations: 1. Preparation of nitrogen-doped graphene oxide: (1) Add graphene oxide to deionized water and ultrasonically disperse for 20 min to obtain a graphene oxide suspension of 1.4 g / L; (2) Add urea to the graphene oxide suspension, ultrasonically disperse for 20 min, and freeze-dry for 48 h to obtain nitrogen-doped graphene oxide; wherein the mass ratio of graphene oxide to urea is 1:3. 2. Preparation of boron-doped graphene oxide: (1) Add graphene oxide to deionized water and ultrasonically disperse for 20 min to obtain a graphene oxide suspension of 1.4 g / L; (2) Add boric acid to the graphene oxide suspension, ultrasonically disperse for 20 min, and freeze-dry for 48 h to obtain boron-doped graphene oxide; wherein the mass ratio of graphene oxide to boric acid is 1:3. 3. Preparation of nitrogen-boron co-doped graphene oxide: (1) Add graphene oxide to deionized water and ultrasonically disperse for 20 min to obtain a graphene oxide suspension of 1.4 g / L; (2) Add urea and boric acid to the graphene oxide suspension, ultrasonically disperse for 20 min, and freeze dry for 48 h to obtain nitrogen-boron co-doped graphene oxide; wherein the mass ratio of graphene oxide, urea and boric acid is 1:1.5:1.5.

[0035] Example 1: A method for preparing a corrosion-resistant alloy material: 1. Preparation of aluminum-based alloy powder: (1) Under an argon atmosphere, the aluminum-based alloy rod was heated to 730℃ and held for 15 minutes to obtain aluminum alloy melt; (2) The aluminum alloy melt flowed into the atomizer at a flow rate of 23g / s, and argon gas was used to impact and atomize the aluminum alloy melt at a pressure of 4MPa to obtain aluminum-based alloy powder. 2. Preparation of graphene / aluminum-based alloy composite powder: (1) Hexadecyltrimethylammonium bromide was added to deionized water and ultrasonically dispersed for 20 min to obtain a 0.3 g / L hexadecyltrimethylammonium bromide solution; aluminum-based alloy powder was added to the hexadecyltrimethylammonium bromide solution and ultrasonically dispersed for 40 min, then filtered, washed, and dried to obtain modified aluminum-based alloy powder; (2) Graphene oxide was added to deionized water and ultrasonically dispersed for 20 min to obtain a 1.5 g / L graphene suspension; modified aluminum-based alloy powder was added to the graphene suspension. Gold powder was stirred and mixed at 55°C for 40 min, and then ascorbic acid was added and stirred and mixed for 1.5 h. After filtration, washing and vacuum drying, a preliminary reduced composite powder was obtained; (3) Under a hydrogen atmosphere, the preliminary reduced composite powder was heated to 350°C and kept warm for 1.5 h to obtain graphene / aluminum alloy composite powder; the amount of hexadecyltrimethylammonium bromide was 1.5 wt% of the mass of aluminum alloy powder; the mass ratio of graphene oxide to modified aluminum alloy powder was 2:100; the amount of ascorbic acid was 1.6 times the mass of graphene oxide; 3. Aluminum-based alloy powder and graphene / aluminum-based alloy composite powder are added to a ball mill and ball-milled for 30 minutes at a speed of 80 r / min using tungsten carbide with a diameter of 9 mm to obtain alloy powder. The alloy powder is then loaded into a mold and placed in a spark plasma sintering furnace. Under vacuum conditions, the pressure is increased to 45 MPa at a pressurization rate of 2 MPa / min. After pressurization, the temperature is increased to 450℃ at a heating rate of 65℃ / min and held for 8 minutes. Then, the pressure is increased to 65 MPa at a pressurization rate of 2 MPa / min and the temperature is increased to 585℃ at a heating rate of 25℃ / min and held for 8 minutes. Finally, the furnace is unloaded when it cools to 100℃ and then cooled to room temperature before being removed to obtain corrosion-resistant aluminum alloy material. The mass ratio of aluminum-based alloy powder to graphene / aluminum-based alloy composite powder is 8.5:1.5.

[0036] Example 2: A method for preparing a corrosion-resistant alloy material: Example 2 is based on Example 1, with the following adjustment: the graphene used is nitrogen-doped graphene oxide, while other processes remain unchanged. Specifically: 2. Preparation of graphene / aluminum-based alloy composite powder: (1) Hexadecyltrimethylammonium bromide was added to deionized water and ultrasonically dispersed for 20 min to obtain a 0.3 g / L hexadecyltrimethylammonium bromide solution; aluminum-based alloy powder was added to the hexadecyltrimethylammonium bromide solution and ultrasonically dispersed for 40 min, then filtered, washed, and dried to obtain modified aluminum-based alloy powder; (2) Nitrogen-doped graphene oxide was added to deionized water and ultrasonically dispersed for 20 min to obtain a 1.5 g / L graphene suspension; modified aluminum-based alloy powder was added to the graphene suspension. Finally, the mixture was stirred at 55°C for 40 min, and ascorbic acid was added and stirred for 1.5 h. After filtration, washing and vacuum drying, a preliminary reduced composite powder was obtained. (3) Under a hydrogen atmosphere, the preliminary reduced composite powder was heated to 350°C and kept at that temperature for 1.5 h to obtain graphene / aluminum alloy composite powder. The amount of hexadecyltrimethylammonium bromide was 1.5 wt% of the mass of the aluminum alloy powder. The mass ratio of nitrogen-doped graphene oxide to modified aluminum alloy powder was 2:100. The amount of ascorbic acid was 1.6 times the mass of nitrogen-doped graphene oxide.

[0037] Example 3: A method for preparing a corrosion-resistant alloy material: Example 3 is based on Example 1, with the following adjustment: the graphene used is boron-doped graphene oxide, while other processes remain unchanged. Specifically: 2. Preparation of graphene / aluminum-based alloy composite powder: (1) Hexadecyltrimethylammonium bromide was added to deionized water and ultrasonically dispersed for 20 min to obtain a 0.3 g / L hexadecyltrimethylammonium bromide solution; aluminum-based alloy powder was added to the hexadecyltrimethylammonium bromide solution and ultrasonically dispersed for 40 min, then filtered, washed, and dried to obtain modified aluminum-based alloy powder; (2) Boron-doped graphene oxide was added to deionized water and ultrasonically dispersed for 20 min to obtain a 1.5 g / L graphene suspension; modified aluminum-based alloy powder was added to the graphene suspension. Finally, the mixture was stirred at 55°C for 40 min, and ascorbic acid was added and stirred for 1.5 h. After filtration, washing and vacuum drying, a preliminary reduced composite powder was obtained. (3) Under a hydrogen atmosphere, the preliminary reduced composite powder was heated to 350°C and kept at that temperature for 1.5 h to obtain graphene / aluminum alloy composite powder. The amount of hexadecyltrimethylammonium bromide was 1.5 wt% of the mass of the aluminum alloy powder. The mass ratio of boron-doped graphene oxide to modified aluminum alloy powder was 2:100. The amount of ascorbic acid was 1.6 times the mass of boron-doped graphene oxide.

[0038] Example 4: A method for preparing a corrosion-resistant alloy material: Example 4 is based on Example 1, with the following adjustment: the graphene used is nitrogen-boron co-doped graphene oxide, while other processes remain unchanged. Specifically: 2. Preparation of graphene / aluminum-based alloy composite powder: (1) Hexadecyltrimethylammonium bromide was added to deionized water and ultrasonically dispersed for 20 min to obtain a 0.3 g / L hexadecyltrimethylammonium bromide solution; aluminum-based alloy powder was added to the hexadecyltrimethylammonium bromide solution and ultrasonically dispersed for 40 min, then filtered, washed, and dried to obtain modified aluminum-based alloy powder; (2) Nitrogen-boron co-doped graphene oxide was added to deionized water and ultrasonically dispersed for 20 min to obtain a 1.5 g / L graphene suspension; modified aluminum-based alloy powder was added to the graphene suspension. Stir and mix at 55°C for 40 min, then add ascorbic acid and stir for 1.5 h. After filtration, washing and vacuum drying, a preliminary reduced composite powder is obtained. (3) Under a hydrogen atmosphere, the preliminary reduced composite powder is heated to 350°C and kept warm for 1.5 h to obtain graphene / aluminum alloy composite powder. The amount of hexadecyltrimethylammonium bromide is 1.5 wt% of the mass of aluminum alloy powder. The mass ratio of nitrogen-boron co-doped graphene oxide to modified aluminum alloy powder is 2:100. The amount of ascorbic acid is 1.6 times the mass of nitrogen-boron co-doped graphene oxide.

[0039] Performance Test 1: The mechanical properties and corrosion resistance of the corrosion-resistant aluminum alloy materials and pure alloy materials prepared in Examples 1-4 were tested. The specific test methods are as follows: 1. Mechanical property testing: The tensile properties of the aluminum alloy material were tested using a universal testing machine at 23℃ and 50% RH at a tensile rate of 2mm / min. 2. Corrosion resistance test: A 5wt% sodium chloride solution with pH=6.5 was prepared and continuously sprayed onto the aluminum alloy material at 35℃ and a spray pressure of 100 kPa, with a mist drop of 1.75 mL / (h·cm). 2 Record the start time of rusting.

[0040] The specific test results are shown in Table 1 below: Table 1

[0041] Result Analysis 1: From the test results in Table 1 above, we can see that: Regarding tensile strength and corrosion resistance: Examples 1-4 all exhibited relatively excellent tensile strength and corrosion resistance; among them, the graphene / aluminum alloy composite powder prepared by modifying aluminum alloy powder with nitrogen-boron co-doped graphene oxide in Example 4 showed the best enhancement effect on the performance of aluminum alloy, while the graphene / aluminum alloy composite powder prepared by modifying aluminum alloy powder with graphene oxide in Example 1 showed the weakest enhancement effect on the performance of aluminum alloy compared to the others.

[0042] Regarding elongation: Example 1 performed best, Example 2 performed worst, and Example 4 was second only to Example 2.

[0043] In summary, whether it is graphene oxide, nitrogen-doped graphene oxide, boron-doped graphene oxide, or nitrogen-boron co-doped graphene oxide, all can significantly enhance the tensile strength and corrosion resistance of aluminum alloys. However, they will significantly reduce the elongation of aluminum alloys. Low elongation means poor toughness and reduced processing performance of aluminum alloys, making them more prone to product defects in subsequent rolling, wire drawing, and other processes.

[0044] Based on the above analysis 1, in order to ensure that the aluminum alloy material has excellent comprehensive performance, the graphene was further adjusted in this invention, and Examples 5 to 7 were set up, as follows: Example 5: A method for preparing a corrosion-resistant alloy material: Example 5 is based on Example 1, with the following adjustment: the graphene used is a mixture of graphene oxide and nitrogen-boron co-doped graphene oxide in a mass ratio of 1:3, while other processes remain unchanged. Specifically: 2. Preparation of graphene / aluminum-based alloy composite powder: (1) Add hexadecyltrimethylammonium bromide to deionized water and ultrasonically disperse for 20 min to obtain a 0.3 g / L hexadecyltrimethylammonium bromide solution; add aluminum-based alloy powder to the hexadecyltrimethylammonium bromide solution and ultrasonically disperse for 40 min, then filter, wash, and dry to obtain modified aluminum-based alloy powder; (2) Add graphene oxide and nitrogen-boron co-doped graphene oxide to deionized water and ultrasonically disperse for 20 min to obtain a 1.5 g / L graphene suspension; add modified aluminum-based alloy powder to the graphene suspension and disperse at 55°C. Stir and mix for 40 min, then add ascorbic acid and stir and mix for 1.5 h. After filtration, washing and vacuum drying, a preliminary reduced composite powder is obtained; (3) Under a hydrogen atmosphere, the preliminary reduced composite powder is heated to 350℃ and kept at that temperature for 1.5 h to obtain graphene / aluminum alloy composite powder; wherein, the amount of hexadecyltrimethylammonium bromide is 1.5 wt% of the mass of aluminum alloy powder; the mass ratio of graphene oxide, nitrogen-boron co-doped graphene oxide and modified aluminum alloy powder is 0.5:1.5:100; the amount of ascorbic acid is 1.6 times the mass of graphene oxide and nitrogen-boron co-doped graphene oxide.

[0045] Example 6: A method for preparing a corrosion-resistant alloy material: Example 6 is based on Example 1, with the following adjustments: the graphene used is a mixture of graphene oxide and nitrogen-boron co-doped graphene oxide at a mass ratio of 1:3.5, while other processes remain unchanged. Specifically: 2. Preparation of graphene / aluminum-based alloy composite powder: (1) Add hexadecyltrimethylammonium bromide to deionized water and ultrasonically disperse for 20 min to obtain a 0.3 g / L hexadecyltrimethylammonium bromide solution; add aluminum-based alloy powder to the hexadecyltrimethylammonium bromide solution and ultrasonically disperse for 40 min, then filter, wash, and dry to obtain modified aluminum-based alloy powder; (2) Add graphene oxide and nitrogen-boron co-doped graphene oxide to deionized water and ultrasonically disperse for 20 min to obtain a 1.5 g / L graphene suspension; add modified aluminum-based alloy powder to the graphene suspension and stir at 55°C. Mix for 40 min, then add ascorbic acid and mix for 1.5 h. After filtration, washing and vacuum drying, a preliminary reduced composite powder is obtained; (3) Under a hydrogen atmosphere, the preliminary reduced composite powder is heated to 350℃ and kept warm for 1.5 h to obtain graphene / aluminum alloy composite powder; wherein, the amount of hexadecyltrimethylammonium bromide is 1.5 wt% of the mass of aluminum alloy powder; the mass ratio of graphene oxide, nitrogen-boron co-doped graphene oxide and modified aluminum alloy powder is 0.44:1.56:100; the amount of ascorbic acid is 1.6 times the mass of graphene oxide and nitrogen-boron co-doped graphene oxide.

[0046] Example 7: A method for preparing a corrosion-resistant alloy material: Example 7 is based on Example 1, with the following adjustment: the graphene used is a mixture of graphene oxide and nitrogen-boron co-doped graphene oxide in a mass ratio of 1:4, while other processes remain unchanged. Specifically: 2. Preparation of graphene / aluminum-based alloy composite powder: (1) Add hexadecyltrimethylammonium bromide to deionized water and ultrasonically disperse for 20 min to obtain a 0.3 g / L hexadecyltrimethylammonium bromide solution; add aluminum-based alloy powder to the hexadecyltrimethylammonium bromide solution and ultrasonically disperse for 40 min, then filter, wash, and dry to obtain modified aluminum-based alloy powder; (2) Add graphene oxide and nitrogen-boron co-doped graphene oxide to deionized water and ultrasonically disperse for 20 min to obtain a 1.5 g / L graphene suspension; add modified aluminum-based alloy powder to the graphene suspension and disperse at 55°C. Stir and mix for 40 min, then add ascorbic acid and stir and mix for 1.5 h. After filtration, washing and vacuum drying, a preliminary reduced composite powder is obtained; (3) Under a hydrogen atmosphere, the preliminary reduced composite powder is heated to 350℃ and kept at that temperature for 1.5 h to obtain graphene / aluminum alloy composite powder; wherein, the amount of hexadecyltrimethylammonium bromide is 1.5 wt% of the mass of aluminum alloy powder; the mass ratio of graphene oxide, nitrogen-boron co-doped graphene oxide and modified aluminum alloy powder is 0.4:1.6:100; the amount of ascorbic acid is 1.6 times the mass of graphene oxide and nitrogen-boron co-doped graphene oxide.

[0047] Performance Test 2: Using the test methods in Performance Test 1, mechanical property tests and corrosion resistance tests were conducted on Examples 5-7. The specific test results are shown in Table 2 below: Table 2

[0048] Result Analysis 2: Comparing the data in Table 2 and Table 1, it can be seen that the graphene / aluminum alloy composite powder prepared by modifying aluminum alloy powder with graphene oxide and nitrogen-boron co-doped graphene oxide significantly enhances the performance of aluminum alloys compared to Example 1. While the tensile strength and corrosion resistance are slightly reduced compared to Example 4, the elongation of the aluminum alloy is enhanced. This indicates that the combination of graphene oxide and nitrogen-boron co-doped graphene oxide can achieve the best performance enhancement for aluminum alloys.

[0049] From the test results of Examples 1 to 7 above, it can be seen that Examples 5 to 7 exhibit superior performance test results. Among them, Example 6 shows the most balanced overall performance. Example 6 is now selected as the best example, and based on it, a comparative experiment is conducted, setting up Comparative Examples 1 and 2, as follows: Comparative Example 1: A method for preparing a corrosion-resistant alloy material: Comparative Example 1 is based on Example 6, with the following adjustment: the aluminum-based alloy powder was not modified using a cationic surfactant, while other processes remained unchanged. Specifically: 2. Preparation of graphene / aluminum alloy composite powder: (1) Add graphene oxide and nitrogen-boron co-doped graphene oxide to deionized water and ultrasonically disperse for 20 min to obtain a graphene suspension of 1.5 g / L; add aluminum alloy powder to the graphene suspension and stir and mix at 55°C for 40 min, then add ascorbic acid and stir and mix for 1.5 h. After filtration, washing and vacuum drying, a preliminary reduced composite powder is obtained; (2) Under hydrogen atmosphere, heat the preliminary reduced composite powder to 350°C and keep it at 1.5 h to obtain graphene / aluminum alloy composite powder; wherein, the mass ratio of graphene oxide, nitrogen-boron co-doped graphene oxide and aluminum alloy powder is 0.44:1.56:100; the amount of ascorbic acid is 1.6 times the mass of graphene oxide and nitrogen-boron co-doped graphene oxide.

[0050] Comparative Example 2: A method for preparing a corrosion-resistant alloy material: Comparative Example 2 is based on Example 6, but with the following adjustment: the mass ratio of aluminum-based alloy powder to graphene / aluminum-based alloy composite powder is 7:3, while other processes remain unchanged, as follows: 3. Aluminum-based alloy powder and graphene / aluminum-based alloy composite powder are added to a ball mill and ball-milled for 30 minutes at a speed of 80 r / min using tungsten carbide with a diameter of 9 mm to obtain alloy powder. The alloy powder is then loaded into a mold and placed in a spark plasma sintering furnace. Under vacuum conditions, the pressure is increased to 45 MPa at a pressurization rate of 2 MPa / min. After pressurization, the temperature is increased to 450℃ at a heating rate of 65℃ / min and held for 8 minutes. Then, the pressure is increased to 65 MPa at a pressurization rate of 2 MPa / min and the temperature is increased to 585℃ at a heating rate of 25℃ / min and held for 8 minutes. Finally, the furnace is unloaded when it cools to 100℃ and then cooled to room temperature before being removed to obtain corrosion-resistant aluminum alloy material. The mass ratio of aluminum-based alloy powder to graphene / aluminum-based alloy composite powder is 7:3.

[0051] Performance Test 3: Using the test methods in Performance Test 1, mechanical property tests and corrosion resistance tests were conducted on Comparative Examples 1 and 2. The specific test results are shown in Table 3 below: Table 3

[0052] Result Analysis 3: As can be seen from the test results in Table 3 above, the present invention achieves the enhancement of the mechanical properties and corrosion resistance of aluminum alloys by adjusting the dosage ratio of graphene / aluminum-based alloy composite powder.

[0053] Those skilled in the art should understand that the present invention is not limited to the details of the exemplary embodiments described above. Other specific embodiments may be adopted without departing from the spirit and essential characteristics of the invention. Therefore, the above embodiments should be considered exemplary only and not restrictive, and the scope of protection of the present invention is defined by the appended claims, not by the foregoing description. All changes within the meaning and scope of the claims and their equivalents should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a corrosion-resistant alloy material, characterized in that: The alloy powder obtained by ball milling and blending aluminum-based alloy powder and graphene / aluminum-based alloy composite powder is loaded into a mold and sintered. The mass ratio of the aluminum-based alloy powder to the graphene / aluminum-based alloy composite powder is (8~9):(1~2); The aluminum-based alloy powder is obtained by atomizing aluminum-based alloy rods using vacuum induction gas atomization technology. The graphene / aluminum-based alloy composite powder was prepared by modifying aluminum-based alloy powder with graphene. The graphene is at least one of graphene oxide and modified graphene oxide. The modified material for the graphene oxide is nitrogen-doped graphene oxide, boron-doped graphene oxide, or nitrogen-boron co-doped graphene oxide.

2. The method for preparing a corrosion-resistant alloy material according to claim 1, characterized in that: The graphene is obtained by mixing and compounding graphene oxide and nitrogen-boron co-doped graphene oxide in a mass ratio of 1:(3~4).

3. The method for preparing a corrosion-resistant alloy material according to claim 1, characterized in that: The vacuum induction gas atomization technology includes the following process parameters: The melting parameters are as follows: the protective gas is argon, the melting temperature is 710~740℃, and the holding time is 10~20min; The atomization parameters are: melt flow rate of 20~25g / s, atomizing gas of argon, and atomization pressure of 3~5MPa.

4. The method for preparing a corrosion-resistant alloy material according to claim 1, characterized in that: The preparation method of the graphene / aluminum-based alloy composite powder is as follows: (1) Add cationic surfactant to deionized water and disperse ultrasonically to obtain a cationic surfactant solution of 0.1~0.5g / L; add aluminum-based alloy powder to the cationic surfactant solution and disperse ultrasonically, then filter, wash and dry to obtain modified aluminum-based alloy powder; (2) Add graphene to deionized water and disperse ultrasonically to obtain a graphene suspension of 1~2g / L; add modified aluminum-based alloy powder to the graphene suspension and stir and mix at 50~60℃, then add ascorbic acid and stir and mix, then filter, wash and vacuum dry to obtain a preliminary reduced composite powder; (3) Under a hydrogen atmosphere, heat the preliminary reduced composite powder to 300~400℃ and keep it warm to obtain graphene / aluminum-based alloy composite powder.

5. The method for preparing a corrosion-resistant alloy material according to claim 4, characterized in that: The amount of the cationic surfactant is 1-2 wt% of the aluminum-based alloy powder; the mass ratio of graphene to modified aluminum-based alloy powder is (1-3):100; the amount of ascorbic acid is 1.2-2 times the mass of graphene.

6. The method for preparing a corrosion-resistant alloy material according to claim 1, characterized in that: The preparation method of the nitrogen-doped graphene oxide, boron-doped graphene oxide, or nitrogen-boron co-doped graphene oxide is as follows: (1) Add graphene oxide to deionized water and disperse it by ultrasonication to obtain a graphene oxide suspension of 0.6~2g / L; (2) Add a nitrogen source or a boron source or a nitrogen source and a boron source to the graphene oxide suspension, disperse it by ultrasonication, freeze dry it to obtain nitrogen-doped graphene oxide, boron-doped graphene oxide, or nitrogen-boron co-doped graphene oxide.

7. The method for preparing a corrosion-resistant alloy material according to claim 6, characterized in that: If nitrogen-doped graphene oxide is prepared, the mass ratio of the graphene oxide to the nitrogen source is 1:(1~5); If boron-doped graphene oxide is prepared, the mass ratio of graphene oxide to boron source is 1:(1~5); If nitrogen-boron co-doped graphene oxide is prepared, the mass ratio of graphene oxide, nitrogen source, and boron source is 1:(0.5~2.5):(0.5~2.5).

8. The method for preparing a corrosion-resistant alloy material according to claim 1, characterized in that: The parameters for ball milling blending are as follows: tungsten carbide balls with a diameter of 8-10 mm are used as grinding balls, the ball milling speed is 60-100 r / min, and the ball milling time is 20-40 min.

9. The method for preparing a corrosion-resistant alloy material according to claim 1, characterized in that: The sintering is spark plasma sintering. The specific sintering process is as follows: the mold containing alloy powder is placed in a spark plasma sintering furnace. Under vacuum conditions, the pressure is increased to 40-50 MPa at a pressurization rate of 1-3 MPa / min. After pressurization, the temperature is increased to 400-500℃ at a heating rate of 50-80℃ / min and held for 5-10 min. Then, the pressure is increased to 60-70 MPa at a pressurization rate of 1-3 MPa / min, and the temperature is increased to 580-590℃ at a heating rate of 20-30℃ / min and held for 5-10 min. Finally, the furnace is unloaded when it cools to 100±5℃, and then cooled to room temperature before being removed.

10. A corrosion-resistant alloy material prepared by the preparation method according to any one of claims 1 to 9.

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