Preparation method of high-temperature-resistant and corrosion-resistant aluminum alloy material
Through mechanical grinding and ultrasonic sintering technology, combined with phenolic gel and fluorination treatment, the strength and corrosion resistance of aluminum alloy materials in high temperature and corrosion environments are solved, and the strength and corrosion resistance of aluminum-magnesium composite materials are significantly improved.
Patent Information
- Application Number
- CN202410978448.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-03
- Publication Date
- 2024-12-10
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Existing aluminum alloy materials have problems of insufficient strength and poor corrosion resistance in high temperature and corrosion environments, especially in applications such as automobile wheel hubs.
Magnesium nitrate hexahydrate, aluminum nitrate nitrate, sodium bicarbonate and other materials are mechanically grounded to prepare aluminum-magnesium hydrotalcite and aluminum lithium hydrotalcite. Through mixed calcination and ultrasonic assisted sintering, uniform alloy grains are formed and coated on the surface of the alloy. Powdered with phenolic gel and fluorination treatment to form a protective film to improve corrosion resistance.
The strength and corrosion resistance of aluminum-magnesium composite materials are significantly improved. Through uniform alloy crystal form development and the carbonized framework structure of phenolic gel, the corrosion resistance of the material is enhanced, and a low-surface energy protective film is formed through fluorination treatment. Prevent corrosion.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of alloy materials, and in particular to a method for preparing a high-temperature resistant and corrosion-resistant aluminum alloy material. Background Art
[0002] Aluminum alloys are widely used in the fields of marine industry, chemical industry, aerospace, metal packaging, transportation, etc. due to their low density, good mechanical properties, good processing performance, non-toxicity, easy recycling, electrical conductivity, and heat transfer. With the rapid development of aluminum alloys, aluminum alloys have been widely used in the manufacture of automobile wheels. Because automobile wheels are exposed to the air for many years and are affected by acid rain, which accelerates corrosion and aging, and also needs to bear a certain amount of pressure, aluminum alloys are required to have good strength and certain corrosion resistance. Summary of the invention
[0003] The purpose of the present invention is to provide a high temperature resistant and corrosion resistant aluminum alloy material and a preparation method thereof, so as to solve the problems existing in the prior art.
[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for preparing a high temperature resistant and corrosion resistant aluminum alloy material, comprising the following preparation steps: (1) Mix magnesium nitrate hexahydrate, aluminum nitrate nonahydrate and sodium bicarbonate, grind at 300-600 rpm for 1-4 h, add distilled water, stir at 300-500 rpm for 30 min, filter, and dry at 100 ° C for 12 h to obtain aluminum magnesium hydrotalcite; (2) Mix lithium nitrate trihydrate and aluminum nitrate nonahydrate, grind at 300-600 rpm for 40-60 min, add deionized water, and then add potassium hydroxide-sodium carbonate until the pH of the reaction solution is 7-9. Continue grinding for 5-9 h, filter, wash with deionized water 6-8 times, and dry at 100 ° C for 12 h to obtain lithium aluminum hydrotalcite; (3) Aluminum-magnesium hydrotalcite and aluminum-lithium hydrotalcite are mixed in a mass ratio of 2:1-5:1, stirred evenly, placed in a muffle furnace, heated to 500-550°C at 10°C / min, roasted for 4-6 hours, cooled to 300-350°C, and then placed in an ultrasonic vibration assisted resistance sintering furnace, heated to 600-700°C at 3-7°C / min, roasted for 0.5-2 hours in a mixed atmosphere, stamped at a pressure of 30-100t, and then sintered at 400-450°C and a pressure of 10MPa for 30-50 minutes to obtain a sheet alloy material with a thickness of 0.2-1.5mm; (4) Spread the sheet alloy material on quartz glass and place it on the lower plate in a pulsed dielectric barrier discharge low-temperature plasma device with a distance of 3 mm between the plates. After passing argon gas and water vapor at a flow ratio of 4:1 for 3 to 5 minutes, start the generator and treat for 30 to 60 seconds to obtain a hydroxylated alloy material. (5) Mix the thermoplastic phenolic resin and the solvent in a mass ratio of 1:6 to 1:9, stir at 60 to 90 rpm for 30 to 60 min, add 0.01 to 0.03 times the mass of the thermoplastic phenolic resin in p-toluenesulfonic acid and 0.01 to 0.03 times the mass of the thermoplastic phenolic resin in diethyl sulfate, stir evenly, react at 80°C for 24 to 48 h to obtain a wet gel, place the wet gel in a solvent 3 to 7 times the mass of the wet gel, soak for 4 days, and replace the solvent once a day to obtain a phenolic gel; (6) The phenolic gel is evenly applied on the plasma-treated side of the hydroxylated alloy material with a thickness of 0.5-2.0 mm, and covered with another piece of hydroxylated alloy material. The material is placed in a refrigerator and frozen for 24-48 hours. The material is then placed in a quartz boat and heated to 350-450°C at a rate of 5-10°C / min under a nitrogen atmosphere. After being kept warm for 3-5 hours, the material is heated to 550-650°C at the same rate and kept warm for 1-2 hours to obtain an intermediate. The intermediate is placed in a 60°C hydrofluoric acid solution with a mass 100 times that of the intermediate. After being soaked for 5-10 minutes, the intermediate is taken out, washed with deionized water for 6-8 times, and dried at 100°C for 8 hours to obtain a high temperature resistant and corrosion resistant aluminum alloy material.
[0005] Furthermore, the grinding ball-to-material ratio in steps (1) and (2) is 10:1-40:1, and the grinding media are zirconia balls with a diameter of 10 mm and a diameter of 6 mm.
[0006] Furthermore, in step (1), the mass ratio of magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, sodium bicarbonate and distilled water is 6:4:1:12-15:4:1:37.5.
[0007] Furthermore, the mass ratio of potassium hydroxide to sodium carbonate in the potassium hydroxide-sodium carbonate in step (2) is 1.2:1.
[0008] Furthermore, in step (2), the mass ratio of lithium nitrate trihydrate, aluminum nitrate nonahydrate and deionized water is 1:5:5-1:8:9.
[0009] Furthermore, in step (3), the power of the ultrasonic wave is 600 W and the frequency is 22 kHz.
[0010] Furthermore, the flow ratio of hydrogen to argon in the mixed atmosphere in step (3) is 1:19.
[0011] Furthermore, in the pulse dielectric barrier discharge low-temperature plasma device in step (4), the voltage is 4 kV, the pulse width is 300 ns, the frequency is 1 kHz, and the positive and negative pulse intervals are 2 μs.
[0012] Furthermore, the solvent in step (5) is a mixture of one or more of ethanol and n-propanol.
[0013] Furthermore, the mass ratio of hydrofluoric acid to deionized water in the hydrofluoric acid solution of step (6) is 0.23:200.
[0014] Compared with the prior art, the beneficial effects achieved by the present invention are: The invention mechanically grinds magnesium nitrate-aluminum nitrate mixture and aluminum nitrate-lithium nitrate to obtain aluminum-magnesium hydrotalcite and aluminum-lithium hydrotalcite respectively. With the above-mentioned raw materials, the metal elements are evenly dispersed, which is conducive to the complete and good development of alloy crystals. After mixed calcination, magnesium and aluminum elements form magnesium oxide and aluminum oxide. At the same time, the hydrotalcite structure is destroyed, so that the lithium element enters the mixed metal oxide. The interaction between magnesium and lithium atoms promotes aluminum-magnesium micro-alloying, which is conducive to improving the strength and corrosion resistance of the aluminum-magnesium composite material. Then, the calcination temperature is further increased to reduce magnesium oxide and aluminum oxide to alloy. Under the assistance of ultrasonic wave, the alloy grains are refined. In the crystallization process, the alloy is in a high-speed vibration state, which reduces agglomeration and promotes The uniform nucleation and growth of alloy grains is beneficial to improving the strength and corrosion resistance of the aluminum-magnesium composite material; the aluminum-magnesium alloy is then pressed into a sheet structure, and after hydroxylation treatment, phenolic gel is coated between two sheets of aluminum-magnesium alloy. The phenolic gel forms hydrogen bonds with the aluminum-magnesium alloy, thereby tightly adhering to the surface of the aluminum-magnesium alloy. After drying and carbonization, a carbon aerogel intermediate skeleton is formed, thereby improving the strength and toughness of the aluminum-magnesium composite material, and in the carbonization process, a carbide reinforcement phase is formed at the interface between the aluminum-magnesium alloy and the aerogel, thereby improving the strength of the aluminum-magnesium composite material, and is also beneficial to improving the corrosion resistance of the aluminum alloy material; and then through fluorination treatment, a low surface energy protective film is formed to prevent the alloy surface from being infiltrated by corrosive liquids. DETAILED DESCRIPTION
[0015] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0016] In order to more clearly illustrate the method provided by the present invention, the following examples are used to describe in detail the various index testing methods of the high temperature resistant and corrosion resistant aluminum alloy materials prepared in the following examples are as follows: Corrosion resistance: The embodiment and the comparative example of the same size were subjected to an acetic acid salt spray test according to GB / T10125. The test temperature was 35° C., the pH value of the acetic acid salt spray was 3.2, and the time when the surface of the alloy material began to corrode was recorded.
[0017] Strength: The tensile strength of the embodiment and the comparative example of the same size was tested according to GB / T228.
[0018] Example 1 (1) Magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, and sodium bicarbonate were mixed in a mass ratio of 6:4:1, with a ball-to-material ratio of 10:1, and ground at 300 rpm for 1 h. The grinding media were zirconium oxide balls with a diameter of 10 mm and 6 mm. Distilled water twice the mass of magnesium nitrate hexahydrate was added, and the mixture was stirred at 300 rpm for 30 min, filtered, and dried at 100°C for 12 h to obtain aluminum-magnesium hydrotalcite. (2) Lithium nitrate trihydrate and aluminum nitrate nonahydrate were mixed in a mass ratio of 1:5, with a ball-to-material ratio of 10:1, and ground at 300 rpm for 40 min. The grinding media were zirconium oxide balls with a diameter of 10 mm and a diameter of 6 mm. Deionized water 5 times the mass of lithium nitrate trihydrate was added, and potassium hydroxide-sodium carbonate was added until the pH of the reaction solution was 7. The mass ratio of potassium hydroxide to sodium carbonate in potassium hydroxide-sodium carbonate was 1.2:1. After grinding for 5 h, the mixture was filtered, washed with deionized water 6 times, and dried at 100°C for 12 h to obtain aluminum-lithium hydrotalcite. (3) Aluminum-magnesium hydrotalcite and aluminum-lithium hydrotalcite were mixed in a mass ratio of 2:1, stirred evenly, placed in a muffle furnace, heated to 500°C at 10°C / min, calcined for 4 hours, cooled to 300°C, and then placed in an ultrasonic vibration-assisted resistance sintering furnace, heated to 600°C at 3°C / min, calcined for 0.5 hours under a mixed atmosphere, a power of 600 W, and a frequency of 22 kHz. The flow ratio of hydrogen to argon in the mixed atmosphere was 1:19. The alloy was stamped at a pressure of 30t, and then sintered at 400°C and a pressure of 10 MPa for 30 minutes to obtain a sheet alloy material with a thickness of 0.2 mm. (4) Spread the sheet alloy material on quartz glass and place it on the lower plate in a pulsed dielectric barrier discharge low-temperature plasma device with a distance of 3 mm between the plates. After introducing argon gas and water vapor at a flow ratio of 4:1 for 3 minutes, start the generator and treat for 30 seconds at a voltage of 4 kV, a pulse width of 300 ns, a frequency of 1 kHz, and a positive and negative pulse interval of 2 μs to obtain a hydroxylated alloy material; (5) Thermoplastic phenolic resin and ethanol were mixed in a mass ratio of 1:6, stirred at 60 rpm for 30 min, and then 0.01 times the mass of the thermoplastic phenolic resin was added with p-toluenesulfonic acid and 0.01 times the mass of the thermoplastic phenolic resin with diethyl sulfate. After stirring evenly, the mixture was reacted at 80°C for 24 h to obtain a wet gel. The wet gel was placed in ethanol 3 times the mass of the wet gel and soaked for 4 days. The solvent was changed once a day to obtain a phenolic gel. (6) The phenolic gel was evenly applied on the plasma-treated side of the hydroxylated alloy material with a thickness of 0.5 mm, and covered with another piece of hydroxylated alloy material. The material was placed in a refrigerator and frozen for 24 hours. The material was placed in a quartz boat and heated to 350°C at a rate of 5°C / min under a nitrogen atmosphere. After being kept warm for 3 hours, the material was heated to 550°C at the same rate and kept warm for 1 hour to obtain an intermediate. The intermediate was placed in a 60°C hydrofluoric acid solution with a mass ratio of hydrofluoric acid to deionized water of 0.23:200. The material was soaked for 5 minutes, taken out, washed with deionized water for 6 times, and dried at 100°C for 8 hours to obtain a high temperature resistant and corrosion resistant aluminum alloy material.
[0019] Example 2 (1) Magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, and sodium bicarbonate were mixed in a mass ratio of 10.5:4:1, and the ball-to-material ratio was 30:1. The grinding process was performed at 450 rpm for 2.5 h. The grinding media was zirconium oxide balls with a diameter of 10 mm and a diameter of 6 mm. Distilled water with a mass of 2.25 times that of magnesium nitrate hexahydrate was added. After stirring at 400 rpm for 30 min, the mixture was filtered and dried at 100° C. for 12 h to obtain aluminum-magnesium hydrotalcite. (2) Lithium nitrate trihydrate and aluminum nitrate nonahydrate were mixed in a mass ratio of 1:6.5, with a ball-to-material ratio of 30:1, and ground at 450 rpm for 50 min. The grinding media were zirconium oxide balls with a diameter of 10 mm and a diameter of 6 mm. Deionized water 7 times the mass of lithium nitrate trihydrate was added, and potassium hydroxide-sodium carbonate was added until the pH of the reaction solution was 8. The mass ratio of potassium hydroxide to sodium carbonate in potassium hydroxide-sodium carbonate was 1.2:1. After grinding for 7 h, the mixture was filtered, washed with deionized water 7 times, and dried at 100°C for 12 h to obtain aluminum-lithium hydrotalcite. (3) Aluminum-magnesium hydrotalcite and aluminum-lithium hydrotalcite were mixed in a mass ratio of 3.5:1, stirred evenly, placed in a muffle furnace, heated to 525°C at 10°C / min, calcined for 5 hours, cooled to 325°C, and then placed in an ultrasonic vibration-assisted resistance sintering furnace, heated to 650°C at 5°C / min, calcined for 1.2 hours under a mixed atmosphere, a power of 600 W, and a frequency of 22 kHz. The flow ratio of hydrogen to argon in the mixed atmosphere was 1:19. The material was stamped under a pressure of 65t, and then sintered at 425°C and a pressure of 10 MPa for 40 minutes to obtain a sheet alloy material with a thickness of 0.9 mm. (4) Spread the sheet alloy material on quartz glass and place it on the lower plate in a pulsed dielectric barrier discharge low-temperature plasma device with a distance of 3 mm between the plates. After introducing argon gas and water vapor at a flow ratio of 4:1 for 4 minutes, start the generator and treat for 45 seconds at a voltage of 4 kV, a pulse width of 300 ns, a frequency of 1 kHz, and a positive and negative pulse interval of 2 μs to obtain a hydroxylated alloy material; (5) Thermoplastic phenolic resin and ethanol were mixed in a mass ratio of 1:7.5, stirred at 75 rpm for 45 min, and then 0.02 times the mass of the thermoplastic phenolic resin of p-toluenesulfonic acid and 0.02 times the mass of the thermoplastic phenolic resin of diethyl sulfate were added, stirred evenly, and reacted at 80°C for 36 h to obtain a wet gel. The wet gel was placed in ethanol 5 times the mass of the wet gel and soaked for 4 days, with the solvent changed once a day to obtain a phenolic gel; (6) The phenolic gel was evenly applied on the plasma-treated side of the hydroxylated alloy material with a thickness of 1.2 mm, and covered with another piece of hydroxylated alloy material. The material was placed in a refrigerator and frozen for 36 hours. The material was then placed in a quartz boat. The temperature was raised to 400°C at a rate of 7°C / min under a nitrogen atmosphere. After being kept warm for 4 hours, the temperature was raised to 600°C at the same rate and kept warm for 1.5 hours to obtain an intermediate. The intermediate was placed in a 60°C hydrofluoric acid solution with a mass ratio of hydrofluoric acid to deionized water of 0.23:200 in the hydrofluoric acid solution. After soaking for 7 minutes, the material was taken out, washed with deionized water for 7 times, and dried at 100°C for 8 hours to obtain a high temperature resistant and corrosion resistant aluminum alloy material.
[0020] Example 3 (1) Magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, and sodium bicarbonate were mixed in a mass ratio of 15:4:1, with a ball-to-material ratio of 40:1, and ground at 600 rpm for 4 h. The grinding media were zirconium oxide balls with a diameter of 10 mm and 6 mm, and distilled water 2.5 times the mass of magnesium nitrate hexahydrate was added. After stirring at 500 rpm for 30 min, the mixture was filtered and dried at 100°C for 12 h to obtain aluminum-magnesium hydrotalcite. (2) Lithium nitrate trihydrate and aluminum nitrate nonahydrate were mixed in a mass ratio of 1:8, with a ball-to-material ratio of 40:1, and ground at 600 rpm for 60 min. The grinding media were zirconium oxide balls with a diameter of 10 mm and 6 mm, and deionized water of 9 times the mass of lithium nitrate trihydrate was added. Potassium hydroxide-sodium carbonate was then added until the pH of the reaction solution was 9. The mass ratio of potassium hydroxide to sodium carbonate in potassium hydroxide-sodium carbonate was 1.2:1. After grinding for 9 h, the mixture was filtered, washed with deionized water for 8 times, and dried at 100°C for 12 h to obtain aluminum-lithium hydrotalcite. (3) Aluminum-magnesium hydrotalcite and aluminum-lithium hydrotalcite were mixed in a mass ratio of 5:1, stirred evenly, placed in a muffle furnace, heated to 550°C at 10°C / min, calcined for 6 hours, cooled to 350°C, and then placed in an ultrasonic vibration-assisted resistance sintering furnace, heated to 700°C at 7°C / min, calcined for 2 hours in a mixed atmosphere at a power of 600 W and a frequency of 22 kHz, the flow ratio of hydrogen to argon in the mixed atmosphere being 1:19, stamped under a pressure of 100t, and then sintered at 450°C and a pressure of 10 MPa for 50 minutes to obtain a sheet alloy material with a thickness of 1.5 mm; (4) Spread the sheet alloy material on quartz glass and place it on the lower plate in a pulsed dielectric barrier discharge low-temperature plasma device with a distance of 3 mm between the plates. After introducing argon gas and water vapor at a flow ratio of 4:1 for 5 minutes, start the generator and treat for 60 seconds at a voltage of 4 kV, a pulse width of 300 ns, a frequency of 1 kHz, and a positive and negative pulse interval of 2 μs to obtain a hydroxylated alloy material; (5) Thermoplastic phenolic resin and n-propanol were mixed in a mass ratio of 1:9, stirred at 90 rpm for 60 min, and then p-toluenesulfonic acid and diethyl sulfate in an amount of 0.03 times the mass of the thermoplastic phenolic resin were added. After stirring evenly, the mixture was reacted at 80°C for 48 h to obtain a wet gel. The wet gel was placed in n-propanol in an amount of 7 times the mass of the wet gel and soaked for 4 days. The solvent was changed once a day to obtain a phenolic gel. (6) The phenolic gel was evenly applied on the plasma-treated side of the hydroxylated alloy material with a thickness of 2 mm, and covered with another piece of hydroxylated alloy material. The material was placed in a refrigerator and frozen for 48 hours. The material was then placed in a quartz boat. The temperature was raised to 450°C at a rate of 10°C / min under a nitrogen atmosphere. After being kept warm for 5 hours, the temperature was raised to 650°C at the same rate and kept warm for 2 hours to obtain an intermediate. The intermediate was placed in a 60°C hydrofluoric acid solution with a mass ratio of hydrofluoric acid to deionized water of 0.23:200. The material was soaked for 10 minutes, taken out, washed 8 times with deionized water, and dried at 100°C for 8 hours to obtain a high temperature resistant and corrosion resistant aluminum alloy material.
[0021] Comparative Example 1 The difference between Comparative Example 1 and Example 2 is that there is no step (2), and step (3) is changed to: the aluminum-magnesium hydrotalcite is placed in a muffle furnace, heated to 525°C at 10°C / min, roasted for 5 hours, cooled to 325°C, and then placed in an ultrasonic vibration assisted resistance sintering furnace, heated to 650°C at 5°C / min, roasted for 1.2 hours under a mixed atmosphere, a power of 600W, and a frequency of 22kHz, wherein the flow ratio of hydrogen to argon in the mixed atmosphere is 1:19, stamped and formed at a pressure of 65t, and then sintered at 425°C and a pressure of 10MPa for 40 minutes to obtain a sheet alloy material with a thickness of 0.9mm. The remaining steps are the same as those of Example 2.
[0022] Comparative Example 2 The difference between Comparative Example 2 and Example 2 is that there are no steps (1) and (2), and step (3) is changed to: aluminum powder, magnesium powder and lithium powder are mixed in a mass ratio of 2:1:0.5, stirred evenly, placed in a muffle furnace, heated to 525°C at 10°C / min, roasted for 5h, cooled to 325°C, and then placed in an ultrasonic vibration assisted resistance sintering furnace, heated to 650°C at 5°C / min, roasted for 1.2h under a mixed atmosphere, a power of 600W, and a frequency of 22kHz, the flow ratio of hydrogen and argon in the mixed atmosphere is 1:19, stamped at a pressure of 65t, and then sintered at 425°C and a pressure of 10MPa for 40min to obtain a sheet alloy material with a thickness of 0.9mm. The remaining steps are the same as those of Example 2.
[0023] Comparative Example 3 The difference between Comparative Example 3 and Example 2 is that step (3) is different. Step (3) is changed to: aluminum-magnesium hydrotalcite and aluminum-lithium hydrotalcite are mixed in a mass ratio of 3.5:1, stirred evenly, placed in a muffle furnace, heated to 525°C at 10°C / min, roasted for 5h, stamped under a pressure of 65t, and then sintered at 425°C and a pressure of 10MPa for 40min to obtain a sheet alloy material with a thickness of 0.9mm. The remaining steps are the same as those in Example 2.
[0024] Comparative Example 4 The difference between Comparative Example 4 and Example 2 is that there is no step (4), and step (6) is changed to: phenolic gel is evenly applied to one side of the sheet alloy material with a thickness of 1.2 mm, covering the other sheet alloy material, placed in a refrigerator, frozen for 36 hours, placed in a quartz boat, heated to 400° C. at 7° C. / min in a nitrogen atmosphere, kept warm for 4 hours, and then heated to 600° C. at the same speed, kept warm for 1.5 hours to obtain an intermediate, and the intermediate is placed in a 60° C. hydrofluoric acid solution with a mass ratio of hydrofluoric acid to deionized water of 0.23:200 in the hydrofluoric acid solution, soaked for 7 minutes, taken out, washed with deionized water 7 times, and dried at 100° C. for 8 hours to obtain a high temperature resistant and corrosion resistant aluminum alloy material. The remaining steps are the same as those in Example 2.
[0025] Comparative Example 5 The difference between Comparative Example 5 and Example 2 is that step (5) is omitted, and step (6) is changed to: placing the hydroxylated alloy material in a 60° C. hydrofluoric acid solution with a mass ratio of hydrofluoric acid to deionized water of 0.23:200, soaking for 7 minutes, taking it out, washing it with deionized water for 7 times, and drying it at 100° C. for 8 hours to obtain a high temperature resistant and corrosion resistant aluminum alloy material. The remaining steps are the same as those in Example 2.
[0026] Comparative Example 6 The difference between Comparative Example 6 and Example 2 lies in the difference in step (6), where step (6) is changed to: smear the phenolic gel evenly on the plasma-treated side of the hydroxylated alloy material to a thickness of 1.2 mm, cover the other hydroxylated alloy material, put it in a refrigerator, freeze it for 36 hours, put it in a quartz boat, and heat it to 400° C. at 7° C. / min in a nitrogen atmosphere, keep it warm for 4 hours, then heat it to 600° C. at the same speed, keep it warm for 1.5 hours to obtain a high temperature resistant and corrosion resistant aluminum alloy material. The remaining steps are the same as those in Example 2.
[0027] Effect example Table 1 below shows the performance analysis results of the high temperature resistant and corrosion resistant aluminum alloy materials using Examples 1 to 3 of the present invention and Comparative Examples 1 to 6.
[0028] Table 1 From the comparison of the experimental data of the embodiment and the comparative example, it can be found that the present invention uses aluminum-magnesium hydrotalcite and aluminum-lithium hydrotalcite as raw materials. Compared with traditional metal powders, the present invention can make the metal elements dispersed evenly, which is conducive to the complete and good development of the alloy crystal form, thereby enhancing the strength of the alloy material. After mixed calcination, the lithium element enters the mixed metal, and the interaction between the magnesium and lithium atoms promotes the micro-alloying of aluminum and magnesium, which is conducive to improving the strength and corrosion resistance of the aluminum-magnesium composite material. Then, under the assistance of ultrasound, the alloy grains are refined, and they are in a high-speed vibration state during the crystallization process to reduce agglomeration and promote uniform nucleation and growth of the alloy grains, which is conducive to improving the strength and corrosion resistance of the aluminum-magnesium composite material; then, phenolic gel is coated between the flaky aluminum-magnesium alloy, and after carbonization, an aerogel intermediate skeleton is formed to improve the strength and toughness of the aluminum-magnesium composite material, and in the carbonization process, a carbide reinforcement phase is formed at the interface between the aluminum-magnesium alloy and the aerogel, thereby improving the strength of the aluminum-magnesium composite material, and is also conducive to improving the corrosion resistance of the aluminum alloy material; and then a low surface energy protective film is formed by fluorination treatment to prevent the alloy surface from being infiltrated by corrosive liquids.
[0029] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the equivalent elements of the claims be included in the invention. Any marking in a claim should not be considered as limiting the claim to which it relates.
Claims
1. A method for preparing a high temperature resistant and corrosion resistant aluminum alloy material, characterized in that: The method comprises the following preparation steps: (1) Magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, and sodium bicarbonate were mixed in a mass ratio of 10.5:4:1, and the ball-to-material ratio was 30:
1. The grinding process was performed at 450 rpm for 2.5 h. The grinding media was zirconium oxide balls with a diameter of 10 mm and a diameter of 6 mm. Distilled water with a mass of 2.25 times that of magnesium nitrate hexahydrate was added. After stirring at 400 rpm for 30 min, the mixture was filtered and dried at 100° C. for 12 h to obtain aluminum-magnesium hydrotalcite. (2) Lithium nitrate trihydrate and aluminum nitrate nonahydrate were mixed in a mass ratio of 1:6.5, with a ball-to-material ratio of 30:1, and ground at 450 rpm for 50 min. The grinding media were zirconium oxide balls with a diameter of 10 mm and a diameter of 6 mm. Deionized water 7 times the mass of lithium nitrate trihydrate was added, and potassium hydroxide-sodium carbonate was added until the pH of the reaction solution was 8. The mass ratio of potassium hydroxide to sodium carbonate in potassium hydroxide-sodium carbonate was 1.2:
1. After grinding for 7 h, the mixture was filtered, washed with deionized water 7 times, and dried at 100°C for 12 h to obtain aluminum-lithium hydrotalcite. (3) Aluminum-magnesium hydrotalcite and aluminum-lithium hydrotalcite were mixed in a mass ratio of 3.5:1, stirred evenly, placed in a muffle furnace, heated to 525°C at 10°C / min, calcined for 5 hours, cooled to 325°C, and then placed in an ultrasonic vibration-assisted resistance sintering furnace, heated to 650°C at 5°C / min, calcined for 1.2 hours under a mixed atmosphere, a power of 600 W, and a frequency of 22 kHz. The flow ratio of hydrogen to argon in the mixed atmosphere was 1:
19. The material was stamped under a pressure of 65t, and then sintered at 425°C and a pressure of 10 MPa for 40 minutes to obtain a sheet alloy material with a thickness of 0.9 mm. (4) Spread the sheet alloy material on quartz glass and place it on the lower plate in a pulsed dielectric barrier discharge low-temperature plasma device with a distance of 3 mm between the plates. After introducing argon gas and water vapor at a flow ratio of 4:1 for 4 minutes, start the generator and treat for 45 seconds at a voltage of 4 kV, a pulse width of 300 ns, a frequency of 1 kHz, and a positive and negative pulse interval of 2 μs to obtain a hydroxylated alloy material; (5) Thermoplastic phenolic resin and ethanol were mixed in a mass ratio of 1:7.5, stirred at 75 rpm for 45 min, and then 0.02 times the mass of the thermoplastic phenolic resin of p-toluenesulfonic acid and 0.02 times the mass of the thermoplastic phenolic resin of diethyl sulfate were added, stirred evenly, and reacted at 80°C for 36 h to obtain a wet gel. The wet gel was placed in ethanol 5 times the mass of the wet gel and soaked for 4 days, with the solvent changed once a day to obtain a phenolic gel; (6) The phenolic gel was evenly applied on the plasma-treated side of the hydroxylated alloy material with a thickness of 1.2 mm, and covered with another piece of hydroxylated alloy material. The material was placed in a refrigerator and frozen for 36 hours. The material was then placed in a quartz boat. The temperature was raised to 400°C at a rate of 7°C / min under a nitrogen atmosphere. After being kept warm for 4 hours, the temperature was raised to 600°C at the same rate and kept warm for 1.5 hours to obtain an intermediate. The intermediate was placed in a 60°C hydrofluoric acid solution with a mass ratio of hydrofluoric acid to deionized water of 0.23:200 in the hydrofluoric acid solution. After soaking for 7 minutes, the material was taken out, washed with deionized water for 7 times, and dried at 100°C for 8 hours to obtain a high temperature resistant and corrosion resistant aluminum alloy material.