High-zinc-content high-strength high-toughness aluminum alloy material and preparation method thereof

Abstract

The present application relates to the technical field of aluminum alloy material, in particular to a high-zinc-content high-strength high-toughness aluminum alloy material and a preparation method thereof.The present application overcomes the problem that current aluminum alloy materials are difficult to balance strength and toughness.In the present application, a melt is prepared by step-by-step melting of aluminum ingot, pure zinc, magnesium, copper metal and aluminum zirconium, aluminum erbium and aluminum silver intermediate alloy, and an alloy powder is obtained by impact atomization;the alloy powder is ball milled with SiC nanoparticles and stearic acid to obtain a composite powder, and a blank ingot is obtained by SPS sintering;after the blank ingot is extruded, solid solution treatment and sectional aging treatment are sequentially performed to obtain the high-zinc-content high-strength high-toughness aluminum alloy material.Through synergistic strengthening of alloy elements and process optimization, good combination of high strength and high toughness is achieved, and the present application is suitable for the field of aerospace.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aluminum alloy materials, in particular to a high-strength and high-toughness aluminum alloy material with high zinc content and a preparation method thereof. BACKGROUND

[0002] Aluminum alloy is one of the cornerstone materials in the modern aerospace industry. Since the early 20th century, with its low density, high specific strength, excellent processing performance, and relatively economical cost, aluminum alloy has been widely used in the design and manufacture of aircraft. From the fuselage, wings, bulkheads to the skin, key load-bearing structural components, the figure of aluminum alloy can be seen everywhere. Especially the high-strength 7xxx series (Al-Zn-Mg-Cu) and the damage tolerance performance excellent 2xxx series (Al-Cu) as the representative of aluminum alloy, after nearly a century of development, has formed a mature material system, providing indispensable material support for the lightweight, high maneuverability and flight safety of the aircraft.

[0003] With the continuous improvement of the performance requirements of new equipment in the aerospace technology, the lightweight and performance limit of the structural materials are put forward more stringent challenges. The core technical bottleneck in the current high-performance aluminum alloy field is the inherent contradiction between "strength" and "toughness". Although the traditional high-strength 7xxx series aluminum alloy (such as 7075, 7055, etc.) can obtain extremely high strength through alloy composition optimization and heat treatment process, but its fracture toughness, stress corrosion cracking (SCC) performance and fatigue crack propagation resistance will decrease. This inverted relationship between strength and toughness greatly limits the application of the material in the key structure which requires high safety redundancy and long service life. Therefore, how to significantly improve the toughness and damage tolerance of the material under the premise of further improving the strength, and break the traditional constraint of "the higher the strength, the worse the toughness", is a key problem to be solved in the research and development of aerospace aluminum alloy materials.

[0004] Therefore, a high-strength and high-toughness aluminum alloy material with high zinc content and a preparation method thereof are provided. SUMMARY

[0005] The present application aims to design a high-strength and high-toughness aluminum alloy material with high zinc content and a preparation method thereof. The present application obtains a melt by step-by-step melting aluminum ingot, pure zinc, magnesium, copper metal and aluminum zirconium, aluminum erbium, aluminum silver intermediate alloy, and obtains alloy powder by impact atomization; the alloy powder is ball milled with SiC nanoparticles and stearic acid to obtain a composite powder, and a blank ingot is obtained by SPS sintering; after the blank ingot is extruded, solid solution treatment and step-by-step aging treatment are sequentially performed to obtain a high-strength and high-toughness aluminum alloy material with high zinc content. Through alloy element synergistic strengthening and process optimization, good combination of high strength and high toughness is achieved, which is suitable for the field of aerospace.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0007] The application provides a preparation method of high-strength and high-toughness aluminum alloy material with high zinc content.

[0008] The aluminum ingot, the pure zinc metal, the pure magnesium metal, the pure copper metal, the aluminum-zirconium intermediate alloy, the aluminum-erbium intermediate alloy and the aluminum-silver intermediate alloy are step-by-step melted to obtain an alloy melt.

[0009] The alloy melt is subjected to impact atomization treatment, and the alloy powder is obtained after cooling and drying.

[0010] The alloy powder, SiC nanoparticles and stearic acid are ground to obtain a composite powder, and the composite powder is placed in a mold and subjected to sintering and heat preservation to obtain an ingot blank.

[0011] The ingot blank is subjected to extrusion molding to obtain an extruded material.

[0012] The extruded material is subjected to solid solution treatment and segmented aging treatment, and is naturally cooled to room temperature to obtain the high-strength and high-toughness aluminum alloy material with high zinc content.

[0013] Preferably, the proportions of the metal elements in the aluminum alloy are as follows: the proportion of zinc is 8.8-10.5%, the proportion of magnesium is 2.2-2.8%, the proportion of copper is 0.9-1.5%, the proportion of zirconium is 0.08-0.15%, the proportion of erbium is 0.1-0.3%, the proportion of silver is 0.1-0.4%, and the balance is aluminum.

[0014] Preferably, the specific process of step-by-step melting is as follows: the aluminum ingot, the pure copper metal, the aluminum-zirconium intermediate alloy, the aluminum-erbium intermediate alloy and the aluminum-silver intermediate alloy are first heated to 750 DEG C for melting in a vacuum environment, after complete melting, high-purity argon is filled to 0.05 MPa under stirring, then the pure zinc metal and the pure magnesium metal are added, the temperature is continuously increased to 770-790 DEG C, and the temperature is maintained for 25-35 min, and the electromagnetic stirring is started at the same time to obtain the alloy melt.

[0015] Preferably, the specific process of impact atomization treatment is as follows: the alloy melt is introduced into a tightly coupled atomization nozzle through a ceramic guide pipe preheated to 800 DEG C, the alloy melt is subjected to impact atomization by using high-purity argon with a pressure of 6-8 MPa, the atomized powder is cooled in a settling tower, and the collected powder is screened in an inert atmosphere glove box, the powder with a particle size of 15-50 mu m is selected and dried in a vacuum oven at 120 DEG C for 4 h to obtain the alloy powder.

[0016] Preferably, the SiC nanoparticles with an average particle size of 40 nm are used and subjected to vacuum drying treatment.

[0017] Preferably, the specific process of the milling treatment and the sintering holding treatment is as follows: the alloy powder, SiC nanoparticles and stearic acid are put into a ball mill, the adding amount of the SiC nanoparticles is 2.5% of the alloy powder, the adding amount of the stearic acid is 0.5% of the alloy powder, the ball-to-material ratio is set to 15:1, the rotating speed is set to 260-300 rpm, the cumulative ball milling time is 6 h, the ball milling is carried out in an intermittent mode of running for 30 min and stopping for 15 min, and the composite powder is obtained after the ball milling; the composite powder is loaded into a graphite mold, slightly vibrated and compacted, and then quickly transferred into a vacuum cavity of an SPS device, rapidly heated at a rate of 100 ℃ / min, and raised to 480 ℃; an uniaxial pressure of 80 MPa is applied, and the temperature and pressure are maintained for 6-12 min at 480 ℃ and 80 MPa; after the holding, the heating is stopped, and the ingot is cooled in the furnace while the pressure is maintained, to obtain an extrusion material.

[0018] Preferably, the specific steps of the extrusion forming treatment are as follows: the ingot is subjected to turning and skin removal, uniformly heated to 320 ℃ in a resistance furnace and maintained for 1 h, quickly transferred into an extruder after preheating, and subjected to hot extrusion at an extrusion ratio of 20:1 and a speed of 0.5-1 mm / s; and the extruded profile is forced air cooled to room temperature to obtain the extrusion material.

[0019] Preferably, the specific steps of the solid solution treatment and the sectional aging treatment are as follows: the extrusion material is put into a soaking furnace preheated to 465-485 ℃ and maintained for 1 h, quickly transferred into room temperature water within 5 s after being taken out of the furnace for quenching; immediately after the quenching, the material is subjected to artificial aging in a constant-temperature oil bath at 100-120 ℃ for 24 h to obtain a T6 state material; the T6 state material is put into a fluidized bed furnace preheated to 190-210 ℃, accurately maintained for 3 min, quickly taken out and quenched in water again to obtain a retrogression treatment material; the retrogression treatment material is aged at 110 ℃ for 8 h, and then the temperature is raised to 150 ℃ and maintained for 10-14 h, and the material is air cooled to room temperature to obtain the high-zinc-content high-strength high-toughness aluminum alloy material.

[0020] In another aspect, the application provides a high-zinc-content high-strength high-toughness aluminum alloy material, and the synthetic raw materials include aluminum ingot, pure zinc metal, pure magnesium metal, pure copper metal, aluminum-zirconium intermediate alloy, aluminum-erbium intermediate alloy, aluminum-silver intermediate alloy and SiC nanoparticles.

[0021] Compared with the prior art, the application has the following beneficial effects:

[0022] 1. Synergistic strengthening of high-Zn matrix and SiC particles, realizing the superposition of chemical strengthening and physical strengthening, and obtaining extremely high comprehensive strength. The high-Zn matrix precipitates a large number of η' phases through aging, providing extremely high matrix strength; and the dispersed SiC nanoparticles as the framework further strengthen the matrix by hindering dislocation movement. More importantly, the high-hardness SiC particles can effectively passivate the micro-cracks that may be induced by high-Zn content, and inhibit their expansion, thereby increasing the strength while maintaining the necessary damage tolerance.

[0023] 2. Synergistic stabilization of Er-Ag micro-alloying and SiC particles, constructing a microstructure extremely stable in thermodynamics. The dispersed phase of Er and Zr is mainly responsible for pinning grain boundaries and sub-boundaries; and SiC particles play a role in physically pinning grain boundaries. This dual pinning effect of chemistry and physics enables the material to maintain ultra-fine grain size without growing during subsequent extrusion forming and heat treatment, laying a foundation for high strength and toughness. At the same time, the addition of Ag element can optimize the precipitates in the matrix / SiC interface region, form a stronger bond, and improve the efficiency of load transfer from the matrix to the SiC particles.

[0024] 3. After ball milling pretreatment, it solves the core problem of uniform dispersion of composite materials from the source. Through ball milling, not only the agglomeration of nano-SiC is completely dispersed and uniformly embedded in the matrix powder, but also a large number of dislocations and lattice distortions are introduced on the powder surface; these "activated" areas will become preferential diffusion channels during subsequent sintering, thereby reducing the sintering temperature, shortening the sintering time, inhibiting grain growth, and obtaining a more fine and uniform dense structure.

[0025] 4. Deformation processing endows the material with a unique micro-damage resistance mechanism. During extrusion forming, the relatively soft aluminum matrix flows around the hard SiC particles, forming a high-density dislocation zone and fine-grained zone around the particles. This flow effect makes the combination of the matrix and SiC more closely. At the same time, this non-uniform micro-strain field and fine structure can induce more complex crack propagation paths when the material is stressed, consuming more fracture energy, thereby significantly improving the fracture toughness of the material.

[0026] 5. The regression step of heat treatment not only can dissolve the coarse chain-shaped precipitates on the matrix grain boundaries, but also can optimize the precipitate morphology and distribution in the SiC / matrix interface region. By adjusting the re-aging process, a "cleaning zone" free of coarse precipitates or discontinuous fine precipitates can be formed at the interface, which can greatly alleviate the interface stress concentration, enhance the interface bonding strength, avoid premature failure due to weak interface, and ultimately make the strength and toughness of the composite material reach the best match. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1Yield strength and tensile rate diagrams of Example 1, Comparative Example 4 and Comparative Examples 9-11 in the present application. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0029] The present application provides a high-zinc-content high-strength high-toughness aluminum alloy material and a preparation method thereof, and the technical solutions are as follows:

[0030] Example 1

[0031] In a vacuum environment, first, the aluminum ingot, pure copper metal, aluminum zirconium intermediate alloy, aluminum erbium intermediate alloy and aluminum silver intermediate alloy are heated to 750 DEG C for melting, after complete melting, high-purity argon gas is filled to 0.05 MPa under stirring, then pure zinc metal and pure magnesium metal are added, and the temperature is further increased to 780 DEG C and kept for 30 min, while the electromagnetic stirring is started, to obtain an alloy melt;

[0032] The alloy melt is introduced into a tightly coupled atomizing nozzle through a ceramic guide pipe preheated to 800 DEG C, and the alloy melt is impacted and atomized by high-purity argon gas with a pressure of 7 MPa, the atomized powder is cooled in a settling tower and collected in an argon-filled collection tank, the collected powder is sieved in an inert atmosphere glove box, the powder with a particle size of 30 μm is selected and dried in a vacuum oven at 120 DEG C for 4 h to obtain an alloy powder;

[0033] The alloy powder, SiC nanoparticles and stearic acid are put into a ball mill, the addition amount of SiC nanoparticles is 2.5% of the alloy powder, the addition amount of stearic acid is 0.5% of the alloy powder, the ball-to-material ratio is set to 15:1, the rotation speed is set to 280 rpm, the cumulative ball milling time is 6 h, and the ball milling is carried out in an intermittent mode of running for 30 min and stopping for 15 min, to obtain a composite powder; the composite powder is loaded into a graphite mold, slightly vibrated and compacted, and then quickly transferred to the vacuum cavity of an SPS device, heated at a rate of 100 DEG C / min, and raised to 480 DEG C, an uniaxial pressure of 80 MPa is applied, and the temperature and pressure are kept at 480 DEG C and 80 MPa for 9 min, after the heat preservation is completed, the heating is stopped, and the furnace is cooled under the condition of maintaining the pressure, to obtain an ingot;

[0034] The billet is turned to remove the surface graphite-rich layer, the billet is uniformly heated to 320 DEG C in a resistance furnace and kept for 1h, the preheated billet is quickly transferred to an extruder to perform hot extrusion, the extrusion ratio is 20:1, the speed is controlled at 0.8mm / s, and the extruded profile is forced air cooled to room temperature to obtain the extruded material;

[0035] The extruded material is placed into a soaking furnace preheated to 475 DEG C and kept for 1h, after being taken out of the furnace, it is quickly transferred into room temperature water within 5s for quenching; after quenching, it is immediately subjected to artificial aging in a constant temperature oil bath at 110 DEG C and kept for 24h to obtain T6 state material; the T6 state material is placed into a fluidized bed furnace preheated to 200 DEG C, kept for 3min accurately, then taken out quickly and subjected to water quenching again to obtain retrogression treated material; the retrogression treated material is aged at 110 DEG C for 8h, then the temperature is increased to 150 DEG C and kept for 12h, and then air cooled to room temperature to obtain high-zinc-content high-strength high-toughness aluminum alloy material;

[0036] According to the mass percentage, the proportion of each metal element in the aluminum alloy of the application is: the proportion of zinc element is 9.8%; the proportion of magnesium element is 2.5%; the proportion of copper element is 1.2%; the proportion of zirconium element is 0.11%; the proportion of erbium element is 0.2%; the proportion of silver element is 0.25%; and the balance is aluminum element.

[0037] Example 1-5 Referring to the parameter conditions in Example 1, the specific differences are shown in Table 1.

[0038] Table 1 Parameter conditions of Examples 1-5

[0039]

[0040] Comparative Example 1 Referring to the parameter conditions in Example 1, the difference lies in that no erbium element is introduced, and others remain unchanged.

[0041] Comparative Example 2 Referring to the parameter conditions in Example 1, the difference lies in that no silver element is introduced, and others remain unchanged.

[0042] Comparative Example 3 Referring to the parameter conditions in Example 1, the difference lies in that no magnesium, copper and zirconium elements are introduced, and others remain unchanged.

[0043] Comparative Example 4 Referring to the parameter conditions in Example 1, the difference lies in that no SiC nanoparticles are added, and others remain unchanged.

[0044] Comparative Example 5 Referring to the parameter conditions in Example 1, the difference lies in that no stearic acid is added, and others remain unchanged.

[0045] Experimental Example 1 Hardness and mechanical strength test

[0046] Tensile strength and yield strength of Examples 1-5 and Comparative Examples 1-5 were tested according to GB / T 228.1-2021; Vickers hardness of Examples 1-5 and Comparative Examples 1-5 was tested according to GB / T 3854-2019; the obtained results are shown in Table 2.

[0047] Table 2 Hardness and mechanical strength of Examples 1-5 and Comparative Examples 1-5

[0048]

[0049] It can be found from Table 2 that, compared with Example 1, the tensile strength, yield strength and surface hardness of Comparative Example 1 all decrease significantly after not introducing erbium element, because in the present alloy system, erbium and zirconium elements synergistically form a high-thermal-stability dispersed phase during high-temperature sintering and thermal deformation, and this particle can strongly pin the grain boundary and subgrain boundary, effectively inhibiting grain growth; lacking the synergistic pinning effect of erbium element, the grain size of the material becomes relatively coarse during high-temperature preparation, and the increase of the grain size directly leads to the decrease of the strength and hardness of the material. The mechanical properties of Comparative Example 2 also decrease obviously compared with Example 1 after not introducing silver element; the core role of silver in the present scheme is a micro-alloying catalyst, which can significantly change the nucleation and growth kinetics of the main strengthening phase, promote the formation of η' phase with smaller size and more dispersed distribution, and improve the thermal stability of the precipitated phase; lacking the catalytic effect of silver, the precipitation strengthening effect of the material during aging treatment will be weakened, the size of the precipitated phase is large and the distribution is uneven, so that the strength and hardness of the material cannot reach the optimal level. Comparative Example 3 removes three key elements of magnesium, copper and zirconium at the same time, resulting in a significant decrease in mechanical properties; magnesium is an essential element for forming the main strengthening phase with zinc, and lacking magnesium, the alloy loses the most fundamental basis for aging strengthening; copper is an important auxiliary strengthening element, and zirconium is a key grain refinement and recrystallization inhibition element; the simultaneous lack of these three elements makes the alloy degenerate into a simple Al-Zn binary alloy, which cannot form effective precipitation strengthening and grain refinement, so its strength and hardness decrease significantly. The removal of SiC nanoparticles in Comparative Example 4 leads to a significant decrease in the overall strength and hardness of the material, which indicates that the high performance of the present application is achieved through the synergistic effect of chemical strengthening of the matrix alloy and physical strengthening of SiC particles. The results of Comparative Example 5 reveal that without adding stearic acid as a process control agent, the soft aluminum alloy powder will be severely cold-welded and agglomerated during ball milling, and at the same time, the SiC nanoparticles cannot be effectively dispersed and uniformly distributed, which leads to a large number of SiC agglomerates and micro-pores in the final sintered material, and these defects as crack sources cause a significant decrease in the mechanical properties of the material.

[0050] Examples 6-9 - Refer to the parameter conditions in Example 1 with the specific differences shown in Table 3.

[0051] Table 3 - Parameter conditions for Example 1 and Examples 6-9

[0052]

[0053] Comparative Example 6 - Refer to the parameter conditions in Example 1 with the difference that instead of step melting, all materials are melted in one step.

[0054] Comparative Example 7 - Refer to the parameter conditions in Example 1 with the difference that after the impact atomization process, the powder is not sieved.

[0055] Comparative Example 8 - Refer to the parameter conditions in Example 1 with the difference that the alloy powder, SiC nanoparticles and stearic acid are not milled.

[0056] Experimental Example 2 - Mechanical strength testing

[0057] The tensile strength and yield strength of Examples 1, 6-9 and Comparative Examples 6-8 were tested according to the method of Experimental Example 1 with the results shown in Table 4.

[0058] Table 4 - Mechanical strength of Examples 1, 6-9 and Comparative Examples 6-8

[0059]

[0060] It can be found from Table 4 that, compared with the step-by-step melting process of Example 1, the one-step melting method of Comparative Example 6 results in a significant decrease in the mechanical strength of the final product. The root cause is that the melting points of magnesium and zinc in the alloy are much lower than those of other components such as aluminum and copper, and they are extremely volatile and oxidized at high temperatures. The long-time heating required for one-step melting to melt high-melting-point components can cause serious "burning loss" of magnesium and zinc, causing the actual composition of the final alloy to deviate from the design value. Since magnesium and zinc are the key to forming the main strengthening phase, the lack of their content directly leads to a significant reduction in the effect of aging precipitation strengthening, thereby causing a significant decrease in the strength of the material. Comparative Example 7 does not perform screening treatment after powder atomization, and its mechanical properties decrease significantly compared with Example 1. This is because the un-screened metal powder has a wide particle size distribution range, containing a large number of fine and coarse particles. This uneven particle size distribution can result in poor powder bulk density, making it difficult to achieve complete densification during subsequent sintering, and easily producing micro-pore defects. At the same time, the wide particle size distribution also affects the uniformity of SiC particles attached to the powder surface during ball milling. Ultimately, these microstructural heterogeneities and defects become mechanical weak points. Comparative Example 8 omits the grinding process, and its mechanical properties have been severely reduced. Ball milling is the key process to achieve uniform dispersion of nano-SiC particles in the metal matrix. If this step is omitted, nano-SiC particles will exist in the form of large-size agglomerates due to their extremely high specific surface energy. During subsequent forming, these hard and brittle SiC agglomerates not only cannot play an effective dispersion strengthening role, but also become a serious stress concentration source, leading to premature failure of the material under stress.

[0061] Examples 10-13 refer to the parameter conditions in Example 1, with specific differences as shown in Table 5.

[0062] Table 5 Parameter conditions of Example 1 and Examples 10-13

[0063]

[0064] Comparative Example 4 refers to the parameter conditions in Example 1, with the difference being that no SiC nanoparticles are added, and the others remain unchanged.

[0065] Comparative Example 9 refers to the parameter conditions in Example 1, with the difference being that no extrusion forming treatment is performed.

[0066] Comparative Example 10 refers to the parameter conditions in Example 1, with the difference being that no solid solution treatment is performed.

[0067] Comparative Example 11 refers to the parameter conditions in Example 1, with the difference being that no segmented aging treatment is performed, and it is obtained by directly water quenching after heat preservation at 200°C.

[0068] Experimental Example 3 Mechanical strength and toughness test

[0069] The tensile strength, yield strength, and elongation were tested according to GB / T 228.1-2021 for Examples 1, 10-13, Comparative Examples 4, and 9-11. The results are shown in Table 6. The yield strength and elongation of Examples 1, 4, and 9-11 are as follows: Figure 1 As shown.

[0070] Table 6 Mechanical strength and toughness of Examples 1, 10-13, Comparative Examples 4 and 9-11

[0071]

[0072] From Table 6 and Figure 1 It can be observed that Comparative Example 4, lacking the addition of SiC nanoparticles, exhibits a significant performance decline. This indicates that the addition of SiC nanoparticles effectively enhances the strength and toughness of the material through dispersion strengthening. As a reinforcing phase, SiC nanoparticles can hinder dislocation movement, thereby improving overall mechanical properties. Comparative Example 9, lacking extrusion molding, shows an even more pronounced performance decline. Extrusion molding refines grains through plastic deformation, increasing material density and reducing internal defects. The absence of this process leads to a loose material structure, coarse grains, and consequently, a significant reduction in strength and plasticity. Comparative Example 10, lacking solution treatment, shows a significant performance decline. Solution treatment allows alloying elements to fully dissolve into the matrix, forming a supersaturated solid solution, laying the foundation for subsequent age-hardening. Without solution treatment, this effect cannot be achieved, resulting in insufficient material strengthening and a substantial reduction in performance. Comparative Example 11, which did not undergo segmented aging treatment and was only subjected to single-temperature holding followed by water quenching, exhibited the worst performance. Segmented aging treatment can control the size, distribution, and quantity of the strengthening phase by observing the precipitation behavior at different temperature stages, thereby achieving a better strengthening effect. In contrast, aging at a single temperature cannot achieve the ideal precipitation state, which further reduces the strength and toughness of the material.

[0073] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a high-zinc-content, high-strength, and high-toughness aluminum alloy material, characterized in that: The preparation method includes the following steps: The alloy melt is obtained by stepwise melting of aluminum ingots, pure zinc metal, pure magnesium metal, pure copper metal, aluminum-zirconium master alloy, aluminum-erbium master alloy, and aluminum-silver master alloy. The proportions of each metallic element in the aluminum alloy, calculated by mass percentage, are as follows: zinc 8.8-10.5%; magnesium 2.2-2.8%; copper 0.9-1.5%; zirconium 0.08-0.15%; erbium 0.1-0.3%; silver 0.1-0.4%; with the balance being aluminum. The alloy melt is subjected to impact atomization treatment, and then cooled and dried to obtain alloy powder. The alloy powder, SiC nanoparticles, and stearic acid are ground to obtain a composite powder; the composite powder is placed in a mold and sintered and heat-preserved to obtain an ingot; the amount of SiC nanoparticles added is 2.5% of the alloy powder, and the amount of stearic acid added is 0.5% of the alloy powder; The billet is subjected to extrusion molding to obtain extruded material; The extruded material is placed in a homogenizing furnace preheated to 465℃-485℃ and held for 1 hour. After being removed from the furnace, it is transferred to room temperature water for quenching within 5 seconds. After quenching, it is artificially aged in a constant temperature oil bath at 100℃-120℃ for 24 hours to obtain the T6 state material. The T6 state material is placed in a fluidized bed furnace preheated to 190℃-210℃ and held for 3 minutes. It is then removed and water-quenched again to obtain the reversion-treated material. The reversion-treated material is aged at 110℃ for 8 hours, then the temperature is raised to 150℃ and held for 10-14 hours. It is then air-cooled to room temperature to obtain the high-zinc-content, high-strength, and high-toughness aluminum alloy material.

2. The method for preparing a high-zinc-content, high-strength, and high-toughness aluminum alloy material according to claim 1, characterized in that: The specific process of the step-by-step melting is as follows: Under vacuum, the aluminum ingot, the pure copper metal, the aluminum-zirconium master alloy, the aluminum-erbium master alloy, and the aluminum-silver master alloy are melted. After complete melting, argon gas is introduced under stirring, and then the pure zinc metal and the pure magnesium metal are added. The mixture is kept heated while electromagnetic stirring is turned on to obtain the alloy melt.

3. The method for preparing a high-zinc-content, high-strength, and high-toughness aluminum alloy material according to claim 1, characterized in that: The specific process of the impact atomization treatment is as follows: the alloy melt is introduced into a tightly coupled atomizing nozzle through a ceramic guide tube preheated to 800°C, and the alloy melt is impact-atomized with argon gas. The atomized powder is cooled in a settling tower and collected in a collection tank filled with argon gas. The collected powder is sieved, and the powder with a particle size of 15-50 μm is selected and vacuum dried to obtain the alloy powder.

4. The method for preparing a high-zinc-content, high-strength, and high-toughness aluminum alloy material according to claim 1, characterized in that: The specific processes of the grinding and sintering heat preservation treatment are as follows: the alloy powder, the SiC nanoparticles and the stearic acid are placed in a ball mill and the cumulative ball milling time is 6 hours. After the ball milling is completed, the composite powder is obtained. The composite powder is loaded into a graphite mold and quickly transferred to a vacuum chamber. The temperature is raised to 480°C and held under pressure for 6-12 minutes. After the heat preservation is completed, the heating is stopped and the ingot is cooled with the furnace under pressure to obtain the billet.

5. The method for preparing a high-zinc-content, high-strength, and high-toughness aluminum alloy material according to claim 1, characterized in that: The specific steps of the extrusion molding process are as follows: the billet is machined and peeled to remove the graphite-rich layer on the surface, then heated to 320°C in a resistance furnace and held for 1 hour, and then quickly transferred to an extruder for hot extrusion. The extruded profile is then forced to air-cool to room temperature to obtain the extruded material.

6. A high-zinc-content, high-strength, and high-toughness aluminum alloy material, characterized in that: The raw materials for synthesizing the high-zinc-content, high-strength, and high-toughness aluminum alloy material include aluminum ingots, pure zinc metal, pure magnesium metal, pure copper metal, aluminum-zirconium master alloy, aluminum-erbium master alloy, aluminum-silver master alloy, and SiC nanoparticles; the high-zinc-content, high-strength, and high-toughness aluminum alloy material is prepared by the preparation method described in any one of claims 1-5.

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