Preparation method of unsteady-state aluminum alloy, unsteady-state aluminum alloy prepared through preparation method and application of unsteady-state aluminum alloy
By adopting non-stable aluminum alloy and rapid hot stamping forming process, the problems of degradation of mechanical properties and long production cycles in traditional aluminum alloy hot stamping forming process are solved, and efficient production and stability of thin-walled aluminum alloy parts are achieved.
Patent Information
- Application Number
- CN202411610697.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-08
- Publication Date
- 2025-02-21
AI Technical Summary
The traditional aluminum alloy hot stamping forming process has problems such as natural aging under supersaturated solid solution, which leads to a decline in mechanical properties, and the long aging treatment time leads to a long production cycle and high cost.
The non-stable aluminum alloy is used, and the percentage of the atomic solute region enriched in its microstructure accounts for more than 80%. Through pre-aging treatment and rapid hot stamping forming process, the high-temperature solution treatment steps are reduced and the aging cycle is shortened.
It realizes long-term stable storage of non-stable aluminum alloys in natural environments, reduces production cycles and costs, and improves the production efficiency and product stability of thin-walled aluminum alloy parts.
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Abstract
Description
[0001] This invention is a divisional application. The basis of the divisional application is the invention application with application number 202410267714.2, the application date is 2024.03.08, and the patent name is non-steady-state aluminum alloy and its preparation method, rapid hot stamping forming parts process and the obtained thin-walled aluminum alloy parts. Technical Field
[0002] The invention relates to the technical field of aluminum alloys, and in particular to a non-steady-state aluminum alloy and a preparation method thereof, a rapid hot stamping part forming process and a prepared thin-walled aluminum alloy part. Background Art
[0003] In response to the demand for large-scale industrial production of parts in the fields of new energy vehicles, rail transit, etc., 6 series and 7 series aluminum alloys have become ideal materials for lightweight parts in the fields of new energy vehicles, rail transit, etc. due to their superior specific strength, corrosion resistance, oxidation resistance and other properties.
[0004] 6 series aluminum alloy is a heat-treatable aluminum alloy with Mg and Si as the main strengthening elements. 5 Si 6 ) phase is its main strengthening phase. 7 series aluminum alloy is a heat-treatable aluminum alloy with Zn and Mg as the main strengthening elements. 2 ) phase is its main strengthening phase. Among them, the 6-series and 7-series aluminum alloys have low plasticity at room temperature, which makes it difficult for the cold stamping process to meet the high-precision forming requirements of complex thin-walled components, that is, components with an overall size greater than 1m, a wall thickness less than 2mm, and features such as holes or grooves less than 5mm. Therefore, aluminum alloy hot stamping forming process is usually used to produce complex thin-walled components.
[0005] At present, the traditional aluminum alloy hot stamping forming process usually first subject the metastable aluminum alloy sheet to solid solution treatment in a heating furnace, then quickly transfer the solution treated aluminum alloy sheet to a cold mold for forming, and complete quenching under pressure, and finally restore the strength of the formed part through artificial aging.
[0006] However, there are two technical bottlenecks in the traditional aluminum alloy stamping process: First, the aluminum alloy that has undergone solid solution treatment is in a supersaturated solid solution state without precipitation phase precipitation after stamping. Long-term storage under natural conditions is prone to cause the natural aging phenomenon of supersaturated solid solution dissolution and precipitation phase gradual precipitation, resulting in a significant decrease in mechanical properties and large performance differences between different batches of products. Second, the aging treatment time for precipitation phase precipitation and strengthening from supersaturated solid solution is too long. For example, the artificial aging time of 6 series aluminum alloy from supersaturated solid solution → atomic cluster → GP zone → β" phase is as long as 4-8 hours, and the artificial aging time of 7 series aluminum alloy from supersaturated solid solution → atomic cluster → GPI zone or GPII zone → η' phase is as long as more than 20 hours, resulting in the problems of too long production cycle and too high production cost, which seriously restricts the large-scale and low-cost industrial production of complex thin-walled aluminum alloy parts. Summary of the invention
[0007] The purpose of the present invention is to provide a non-stable aluminum alloy and a preparation method thereof, a rapid hot stamping part forming process and the resulting thin-walled aluminum alloy parts, wherein the non-stable aluminum alloy can be stored stably for a long time, thereby improving the production flexibility of thin-walled aluminum alloy parts. In addition, the non-stable aluminum alloy can be used to form aluminum alloy parts with complex thin-walled structures in an integrated manner, and can significantly shorten the aging cycle or replace it with baking varnish while ensuring strength, thereby meeting the common core needs of "improving quality and efficiency" in the forming and manufacturing of complex thin-walled aluminum alloy parts.
[0008] In a first aspect, the present invention provides a non-steady-state aluminum alloy as follows: A non-stable aluminum alloy, wherein the percentage of atomic solute-enriched areas in the microstructure of the non-stable aluminum alloy is more than 80%.
[0009] The solute elements in the non-steady-state aluminum alloy defined in the present invention have been precipitated in large quantities and evenly distributed, which greatly improves the activation energy for further precipitation of the strengthening phase and suppresses the parking effect. The alloy can be stored for a long time in a natural environment without changes in mechanical properties, thereby effectively improving the production flexibility and product stability of thin-walled aluminum alloy parts.
[0010] Among them, the unstable state defined in the present invention is different from the traditional metastable state in two points: First, the metastable precipitation phase of 6 series aluminum alloy is mainly β" phase (the percentage of quantity is more than 80%), and the 7 series aluminum alloy is mainly η' phase (the percentage of quantity is more than 80%), while the unstable precipitation phase of 6 series aluminum alloy is mainly GP zone (the percentage of quantity is more than 80%), and the 7 series aluminum alloy is mainly GPII zone (the percentage of quantity is more than 80%).
[0011] Second, the metastable precipitate phase can remain stable for a long time at room temperature, but has low plasticity. When stamping into thin-walled aluminum alloy parts, it needs to be re-solidified, then stamped and aged, resulting in long production cycles and low efficiency. The non-stable precipitate phase can not only remain stable for a long time at room temperature, but also does not require high-temperature solution treatment when forming thin-walled aluminum alloy parts, which can save process steps, reduce energy consumption, save production costs, and improve the production efficiency of thin-walled aluminum alloy parts.
[0012] In a second aspect, the present invention provides a method for preparing a non-stable aluminum alloy using the following technical solution: The preparation method of the non-stable aluminum alloy comprises the following steps: Sa. performing solid solution and quenching treatment on the supplied aluminum alloy sheet to obtain a supersaturated solid solution aluminum alloy sheet; Sb, pre-aging treatment is performed on the supersaturated solid solution aluminum alloy sheet material, so that the percentage of atomic solute enriched areas in the microstructure of the supersaturated solid solution aluminum alloy sheet material accounts for more than 80% and is uniformly distributed, thereby obtaining a non-steady-state aluminum alloy.
[0013] Optionally, the as-supplied aluminum alloy sheet is any one of a 6-series as-supplied aluminum alloy sheet and a 7-series as-supplied aluminum alloy sheet.
[0014] The non-stable aluminum alloy defined in the Sb step of the present invention refers to a state in which the atomic solute-rich area in the microstructure precipitation phase of the aluminum alloy accounts for more than 80%. Specifically, the non-stable state of the 6-series aluminum alloy refers to a state in which the GP area in the microstructure precipitation phase accounts for more than 80%; the non-stable state of the 7-series aluminum alloy refers to a state in which the GPII area in the microstructure precipitation phase accounts for more than 80%.
[0015] Optionally, when the supplied aluminum alloy sheet material is a 6 series supplied aluminum alloy sheet material: In Sa, the solution treatment is carried out at 530-550°C and the solution treatment time is 25-35min; In Sb, the pre-aging treatment is carried out at 160-200°C, the pre-aging treatment time is 70-120min, and the atomic solute enriched area is the GP area.
[0016] The strengthening phase elements of the supersaturated solid solution 6 series aluminum alloy sheet have been dissolved in the aluminum matrix. After being treated at 160-200℃ for 70-120min to reach a non-steady state, the strengthening phase elements are uniformly precipitated and form a large number of GP zones and a small amount of β" phase, which not only consumes the solute elements, but also increases the activation energy of the further evolution and precipitation of the precipitate phase, so that the 6 series aluminum alloy in this state can be stored for a long time in the natural environment. Among them, in Sa, the solution treatment time should not exceed the range of 25-35min. If the time is too short, the solid solution degree is low. If the time is too long, it is easy to overburn, and the local melting of the grain boundary, microscopic voids, blackening of the surface, bubbles and fractures will occur, which seriously affect the performance of the aluminum alloy. In Sb, if the pre-aging treatment time is less than 70min, the atomic solute enriched zone cannot form a GP zone, or too little is formed, and the performance after subsequent aging is low; if the pre-aging treatment time is more than 120min, the atomic solute enriched zone will further evolve, the forming performance of thin-walled aluminum alloy parts will decrease, and the performance after aging will be low.
[0017] Optionally, when the supplied aluminum alloy sheet material is a 7 series supplied aluminum alloy sheet material: In Sa, the solution treatment is carried out at 480-500°C and the solution treatment time is 25-35min; In Sb, the pre-aging treatment is carried out at 110-140°C, the pre-aging treatment time is 30-100 min, and the atomic solute enriched area is the GPII area.
[0018] The strengthening phase elements of the supersaturated solid solution 7 series aluminum alloy sheet have been dissolved in the aluminum matrix. After being treated at 110-140℃ for 30-100min to reach a non-stable state, the strengthening phase elements are uniformly precipitated and form a large number of GPII zones and a small amount of η′ phase, which not only consumes the solute elements, but also increases the activation energy of the precipitation phase for further evolution and precipitation, so that the 7 series aluminum alloy in this state can be stored for a long time in the natural environment. Among them, for Sa, the solid solution treatment time should not exceed the range of 25-35min. If the time is too short, the solid solution degree is low. If the time is too long, it is easy to overburn, and the local melting of the grain boundary, microscopic voids, black surface, bubbles and fractures will occur, which seriously affect the performance of the aluminum alloy. For Sb, if the pre-aging treatment time is less than 30min, the atomic solute enriched zone cannot form the GPII zone, or the formation is too small, and the performance after subsequent aging is low; if the pre-aging treatment time is more than 100min, the atomic solute enriched zone will further evolve, the forming performance of thin-walled aluminum alloy parts will decrease, and the performance after aging will be low.
[0019] In a third aspect, the present invention provides a rapid hot stamping forming process for a non-steady-state aluminum alloy part using the following technical solution: A rapid hot stamping forming process for non-steady-state aluminum alloy parts comprises the following steps: S1. heating the unstable aluminum alloy to a temperature between recrystallization and solid solution, with a heating rate greater than a critical heating rate, to ensure that the percentage of the amount of dissolved atomic-rich solute in the unstable aluminum alloy is no more than 10%; S2, transferring the non-steady-state aluminum alloy after the heat treatment to a cold die within 1-5 seconds for stamping to obtain an aluminum alloy part, and then quenching under pressure, so that the microstructure of the aluminum alloy part still maintains a non-steady state in which the number percentage of the atomic solute-enriched area accounts for more than 80%; S3. The aluminum alloy parts after pressure-holding quenching are subjected to baking varnish or aging treatment, the temperature of baking varnish or aging treatment is 160-200° C., and the time is 20-50 min, so as to obtain aluminum alloy parts in which the number percentage of metastable state in the precipitated phase is more than 80%.
[0020] In the present invention, a non-stable aluminum alloy capable of long-term stable storage is used as a raw material for forming thin-walled aluminum alloy parts. Secondly, the heating rate is controlled to be greater than the critical heating rate in S1 to ensure that the quantitative percentage of the dissolved amount of the atomic solute enriched area in the non-stable aluminum alloy is not higher than 10%, and the specific heating rate is selected according to different aluminum alloys; in addition, the non-stable aluminum alloy after the heat treatment is transferred to a cold mold for stamping forming within 1-5s. Through the coordination of rapid heating and rapid transfer, a large amount of dissolution of the atomic solute enriched area of the non-stable aluminum alloy during the heating process can be prevented, so that rapid strengthening can be achieved through a short time of baking paint or artificial aging treatment, which is conducive to the rapid integrated forming of complex thin-walled aluminum alloy parts, thereby realizing large-scale, low-cost and stable industrial production of aluminum alloy parts.
[0021] Optionally, when the non-steady-state aluminum alloy uses a 6-series supplied aluminum alloy sheet as the supplied aluminum alloy sheet: In S1, the heating rate is 30-80°C / s, the temperature between recrystallization and solid solution is 360-480°C, and the atomic solute-rich region is the GP region; In S2, the cooling rate during pressure-holding quenching is controlled above 50°C / s, and the atomic solute-enriched area is the GP area; In S3, the metastable state of the aluminum alloy part is that the precipitation phase is mainly β" phase.
[0022] After the 6 series non-steady-state aluminum alloy is quickly heated to 360-480℃, the ductility of the aluminum alloy is greatly improved and the large-scale dissolution of the precipitate phase is prevented; then, it is painted or aged at 160-200℃ for 20-50min, which can prompt the GP zone to quickly transform into the β" phase, forming a state where the β" phase accounts for more than 80%, and there are a small amount of GP zone and β' phase. Under the joint effect of dislocation strengthening, the mechanical properties of the stamped aluminum alloy parts are efficiently enhanced, and the strength of the final stamped aluminum alloy parts reaches 98%-103% of the T6 state.
[0023] Optionally, when the non-steady-state aluminum alloy uses 7 series supplied aluminum alloy sheet material as the supplied aluminum alloy sheet material: In S1, the heating rate is 30-80°C / s, the temperature between recrystallization and solid solution is 360-480°C, and the atomic solute-rich region is the GPII region; In S2, the cooling rate during pressure-holding quenching is controlled above 100°C / s, and the atomic solute-enriched region is the GPII region; In S3, the metastable state of the aluminum alloy part is that the precipitation phase is mainly η′ phase.
[0024] After rapidly heating the 7 series non-steady-state aluminum alloy to 360-480°C, the ductility of the aluminum alloy is greatly improved and the massive dissolution of the precipitated phase is prevented; subsequently, baking or aging treatment at 160-200°C for 20-50 minutes can promote the rapid transformation of the GPII zone into the η′ phase, forming a state in which the η′ phase accounts for more than 80%, and a small amount of GPII zone and η phase exist at the same time. Under the joint effect of dislocation strengthening, the mechanical properties of the stamped aluminum alloy parts are efficiently enhanced, and finally the strength of the stamped aluminum alloy parts reaches 97%-102% of the T6 state.
[0025] Optionally, in Sa, the state of the supplied aluminum alloy sheet includes but is not limited to T4 state (natural aging after solution treatment), T6 state (artificial aging after solution treatment), O state (annealing state), and F state (free processing state).
[0026] Optionally, in S1, the heating method includes but is not limited to contact heating and self-resistance heating.
[0027] Optionally, the 6 series aluminum alloy sheets in supply state include but are not limited to 6A02 aluminum alloy, 6061 aluminum alloy, 6082 aluminum alloy, 6160 aluminum alloy, 6125 aluminum alloy, 6262 aluminum alloy, 6060 aluminum alloy, 6005 aluminum alloy, 6463 aluminum alloy, 6063 aluminum alloy, 6061 aluminum alloy, and 6111 aluminum alloy.
[0028] Optionally, the 7 series aluminum alloy sheets include but are not limited to 7005 aluminum alloy, 7039 Aluminum alloy, 7049 aluminum alloy, 7050 aluminum alloy, 7075 aluminum alloy, 7175 aluminum alloy, 7178 aluminum alloy, 7475 aluminum alloy, 7A04 aluminum alloy.
[0029] In a fourth aspect, a thin-walled aluminum alloy part disclosed in the present application adopts the following technical solution: A thin-walled aluminum alloy part is produced by any of the above-mentioned non-steady-state aluminum alloy rapid hot stamping forming parts processes.
[0030] Compared with the prior art, the present invention has the following beneficial technical effects: 1. In the present invention, the non-stable aluminum alloy refers to an aluminum alloy in which the percentage of atomic solute-enriched areas in the microstructure is more than 80%. The non-stable aluminum alloy is used to replace the traditional metastable aluminum alloy to produce thin-walled aluminum alloy parts. The non-stable aluminum alloy can not only remain stable at room temperature for a long time, but also does not need to be re-solution-treated at high temperature when forming thin-walled aluminum alloy parts, which can save process steps, reduce energy consumption, save production costs, and improve the production efficiency of thin-walled aluminum alloy parts.
[0031] 2. The present invention obtains a supersaturated solid solution aluminum alloy by performing solid solution and quenching treatment on aluminum alloy sheets, and then performs pre-aging treatment on the supersaturated solid solution aluminum alloy at a specific temperature to achieve a non-stable state. The solute elements in the non-stable aluminum alloy have been precipitated in large quantities and are evenly distributed, which greatly improves the activation energy for further precipitation of the strengthening phase and suppresses the parking effect, so that the non-stable aluminum alloy can be stored for a long time in a natural environment, thereby improving the flexibility of production.
[0032] 3. The present invention uses a non-stable aluminum alloy that can be stored stably for a long time as a raw material for forming thin-walled aluminum alloy parts, and combines rapid heating and rapid transfer of the non-stable aluminum alloy, which can prevent the large-scale dissolution of atomic solute enriched areas during the heating and forming process of the non-stable aluminum alloy. After the thin-walled aluminum alloy parts are formed, they can be parked for a long time and can quickly restore their strength through a short period of artificial aging or baking paint. The aging strengthening cycle of several hours is shortened to tens of minutes or replaced by baking paint, which greatly improves production efficiency and can realize large-scale, low-cost and stable industrial production of thin-walled aluminum alloy parts.
[0033] 4. The present invention forms parts through rapid hot stamping of non-steady-state aluminum alloy, which can meet the high-precision requirements of thin-walled aluminum alloy parts with an overall size greater than 1m, an average wall thickness less than 2mm, and features such as holes or grooves less than 5mm. BRIEF DESCRIPTION OF THE DRAWINGS
[0034] Figure 1 This is a process flow chart of a rapid hot stamping process for aluminum alloy parts in this application.
[0035] Figure 2 This is a TEM photograph of the non-steady-state aluminum alloy obtained in the Sb step in Example Group 1 of the present application.
[0036] Figure 3 This is a TEM photograph of the aluminum alloy part obtained in step S3 of Example Group 1 of the present application.
[0037] Figure 4 This is a TEM photograph of the non-steady-state aluminum alloy obtained in the Sb step in Example Group 2 of the present application.
[0038] Figure 5 This is a TEM photograph of the aluminum alloy part obtained in step S3 of Example Group 2 of the present application. DETAILED DESCRIPTION Example
[0039] [Example Group 1] A non-steady-state aluminum alloy rapid hot stamping forming process, referring to Figure 1 , its production process includes the following steps: Preparation of non-steady-state aluminum alloy: Sa, the T6 state 6111 aluminum alloy sheet was solution treated at 540°C for 35 minutes, followed by water quenching to obtain a supersaturated solid solution aluminum alloy sheet; Sb, treating the supersaturated solid solution 6111 aluminum alloy at 160°C for 90 min to reach a non-steady state, and obtaining a non-steady state aluminum alloy with a GP zone ratio of 90±5%; Part forming: S1, heating the non-steady-state aluminum alloy to 450°C at a rate of 60°C / s; S2, transferring the non-steady-state aluminum alloy after the heating treatment to a cold die within 2 seconds for stamping to obtain an aluminum alloy part, and then quenching under pressure in the die at a quenching cooling rate of 107°C / s; S3. The aluminum alloy part after pressure quenching is subjected to baking paint or aging treatment at 180° C. for 30 min to obtain an aluminum alloy part, wherein the β" phase accounts for 85±5%.
[0040] [Example Group 2] A non-steady-state aluminum alloy rapid hot stamping forming parts process, the production process comprises the following steps: Preparation of non-steady-state aluminum alloy: Sa, the T6 state 7075 aluminum alloy sheet is solution treated at 480°C for 30 minutes, followed by water quenching to obtain a supersaturated solid solution aluminum alloy sheet; Sb, treating the supersaturated solid solution 7075 aluminum alloy at 130°C for 70 minutes to reach a non-steady state, thereby obtaining a non-steady aluminum alloy; obtaining a non-steady aluminum alloy in which the GPII region accounts for 85±5%; Part forming: S1, heating the non-steady-state aluminum alloy to 400°C at a rate of 40°C / s; S2, transferring the non-steady-state aluminum alloy after the heating treatment to a cold die within 2 seconds for stamping to obtain an aluminum alloy part, and then quenching under pressure in the die at a quenching cooling rate of 152°C / s; S3. The aluminum alloy part after pressure quenching is subjected to baking paint or aging treatment at 180° C. for 30 minutes to obtain an aluminum alloy part, in which the η′ phase accounts for 90±5%.
[0041] Performance testing 1. Hardness test of unstable aluminum alloy: The unstable aluminum alloys obtained in the Sb step in Example Group 1 and Example Group 2 were stored for three months respectively, and the Vickers hardness test was performed on the unstable aluminum alloys with different storage times. Three unstable aluminum alloy samples were randomly selected from each example group, and three points of each unstable aluminum alloy sample were randomly selected for hardness test, and the summary results were recorded in the following Table 1.
[0042] Table 1 2. Aluminum alloy parts: Standard tensile test pieces were cut from the aluminum alloy parts obtained in step S3 of Example Group 1 and Example Group 2, respectively, and then uniaxial tensile tests were performed using a universal testing machine with reference to GB / T 228.1-2021 "Tensile Test of Metallic Materials Part 1: Room Temperature Test Method". Three aluminum alloy part specimens were randomly selected from each example group for tensile tests at a test temperature of 25°C, and the tensile strength, yield strength, and elongation at break of the aluminum alloy parts were summarized and recorded in Table 2 below.
[0043] Table 2 3. A transmission electron microscope was used to observe the precipitation state of the precipitated phase of the non-steady-state aluminum alloy obtained in each embodiment group and the precipitation state of the precipitated phase near the fracture of the aluminum alloy part.
[0044] A non-steady-state aluminum alloy sample obtained in the Sb step of Example Group 1 was randomly selected. The TEM photo of the non-steady-state aluminum alloy sample is shown in FIG. Figure 2 ,Among them, the average size distribution of the microstructure precipitation phase of the non-steady-state aluminum alloy is 5.5nm, and the proportion of GP zone is 93.6%.
[0045] An aluminum alloy part sample obtained in step S3 of Example Group 1 was randomly selected. The TEM photo of the aluminum alloy part sample is shown in FIG. Figure 3 Among them, the average size distribution of the microstructure precipitation phase of the aluminum alloy part is 19.9nm, and the proportion of β" phase is 89.2%.
[0046] A non-steady-state aluminum alloy sample obtained in the Sb step of Example Group 2 was randomly selected. The TEM photo of the non-steady-state aluminum alloy sample is shown in FIG. Figure 4 ,Among them, the average size distribution of the microstructure precipitation phase of the non-steady-state aluminum alloy is 4.8nm, and the proportion of GPII zone is 83.3%.
[0047] An aluminum alloy part sample obtained in step S3 of Example Group 2 was randomly selected. The TEM photo of the aluminum alloy part sample is shown in FIG. Figure 5 Among them, the average size distribution of the microstructure precipitation phase of the aluminum alloy part is 9.1nm, and the proportion of η′ phase is 94.1%.
[0048] In summary, the non-steady-state high-strength aluminum alloy sheet obtained by the present invention can be stably stored for a long time, which meets the actual industrial production requirements; after the non-steady-state high-strength aluminum alloy is hot stamped and rapidly strengthened, the strength can reach more than 95% of the T6 state, and the aging strengthening cycle is shortened from several hours to tens of minutes or replaced by baking paint, which greatly improves production efficiency and reduces manufacturing costs.
[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A method for preparing a non-stable aluminum alloy, characterized in that: The following steps are involved: Sa, performing solid solution and quenching treatment on the supplied aluminum alloy sheet to obtain a supersaturated solid solution aluminum alloy sheet; Sb, pre-aging treatment is performed on the supersaturated solid solution aluminum alloy sheet material, so that the number of atomic solute-enriched areas in the microstructure of the supersaturated solid solution aluminum alloy accounts for more than 80% and is uniformly distributed, thereby obtaining the non-steady-state aluminum alloy.
2. The method for preparing a non-stable aluminum alloy according to claim 1, characterized in that: When the supplied aluminum alloy sheet material is a 6 series supplied aluminum alloy sheet material: In Sa, the solution treatment is carried out at 530-550°C and the solution treatment time is 25-35min; In Sb, the pre-aging treatment is carried out at 160-200°C and the pre-aging treatment time is 70-120min; The atomic solute-enriched area is the GP area, the number of which accounts for more than 80% and is evenly distributed.
3. The method for preparing a non-stable aluminum alloy according to claim 1, characterized in that: When the supplied aluminum alloy sheet material is a 7 series supplied aluminum alloy sheet material: In Sa, the solution treatment is carried out at 480-500°C and the solution treatment time is 25-35min; In Sb, the pre-aging treatment is carried out at 110-140°C and the pre-aging treatment time is 30-100min. The atomic solute-enriched area is the GPII area, the number of GPII areas accounts for more than 80%, and is evenly distributed.
4. The method for preparing a non-stable aluminum alloy according to any one of claims 1 to 3, characterized in that: In Sa, the states of the supplied aluminum alloy sheet include T4 state, T6 state, O state, and F state.
5. A non-stable aluminum alloy, characterized in that: The non-steady-state aluminum alloy is prepared by the preparation method of any one of claims 1 to 4.
6. An application of a non-stable aluminum alloy as claimed in claim 5, characterized in that: Used for preparing thin-walled aluminum alloy parts.
7. The use of a non-stable aluminum alloy according to claim 6, characterized in that: The thin-walled aluminum alloy parts are thin-walled aluminum alloy parts with an average wall thickness of less than 2 mm and features such as holes or grooves less than 5 mm.