High strength aluminum lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment method

Abstract

This invention provides a method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment, relating to the technical field of aluminum alloy friction stir deposition additive manufacturing. The method includes: fixing a substrate and placing a stirring head in the area to be added to the substrate; loading a base material into the stirring head; starting the program, with a push rod slowly pushing the aluminum-lithium alloy base material to the area to be added; when the aluminum-lithium alloy base material reaches a thermoplastic state, the stirring head advances to complete deposition; lifting the stirring head and adjusting the height of the end face of the stirring head relative to the deposited layer to perform reverse-direction additive manufacturing to complete deposition; repeating the deposition steps layer by layer upwards until the height of the deposited layer reaches the target height to obtain a friction stir deposition additive component; subjecting the friction stir deposition additive component to low-temperature solution treatment and a first aging treatment, followed by high-temperature solution treatment and a second aging treatment to obtain a high-strength aluminum-lithium alloy, effectively solving the problems of difficult forming and easy cracking of ultra-large and moderately complex aluminum-lithium alloy structural parts.

Description

Technical Field

[0001] This invention belongs to the technical field of aluminum alloy friction stir deposition additive manufacturing, specifically, it relates to a method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment. Background Technology

[0002] To improve the effective payload capacity of launch vehicles, it is imperative to achieve lightweighting of rocket body structural components. The application of lightweight, high-performance materials is an important way to achieve this. Compared with conventional aluminum alloys such as 2A14, 2024, and 2219, aluminum-lithium alloys have lighter weight and higher strength, enabling greater lightweighting of rocket body structural components.

[0003] Traditional methods for manufacturing structural components include casting, forging, and machining. However, the preparation of ultra-large 2195 aluminum-lithium alloy ingots is difficult, and homogeneous forging is challenging, making the integrated fabrication of ultra-large 2195 aluminum-lithium alloy structural components an international challenge. Therefore, there is an urgent need to develop new integrated forming technologies for ultra-large aluminum-lithium alloy structural components. Friction stir deposition additive manufacturing technology provides a new approach for the efficient and flexible manufacturing of large-size aluminum-lithium alloy structural components.

[0004] However, the poor formability of aluminum-lithium alloys poses a challenge to the stable forming of aluminum-lithium alloys through friction stir deposition additive manufacturing. Furthermore, aluminum alloys prepared under dynamic thermo-mechanical coupling are prone to abnormal grain growth during subsequent heat treatment, significantly deteriorating the material's strength and toughness. Therefore, it is urgent to explore methods for manufacturing high-strength aluminum-lithium alloys through friction stir deposition additive manufacturing and multi-stage heat treatment.

[0005] Patent document CN115519136A discloses an additive manufacturing apparatus and a solid-phase additive manufacturing method for hollow parts. The apparatus comprises a feeding tool, a tool head, a mold, and a substrate, forming a variable-volume mold cavity. The lower part of the feeding tool protrudes downwards relative to the bottom end of the tool head. The feeding tool is a hollow structure, and its sidewall has a discharge channel communicating with the mold cavity. The method includes feeding powdered raw material into the mold cavity, controlling the rotation of the substrate, controlling the rotation of the tool head and moving it axially downwards under forging pressure, and allowing the powdered raw material flowing from the discharge channel to spread along the bottom end of the tool head and deposit on the upper surface of the substrate. However, patent document CN115519136A has difficulty in fabricating large-size, high-performance aluminum-lithium alloy solid structural parts, such as rocket connecting rings. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment.

[0007] A method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to the present invention includes:

[0008] Step S1: Prepare the substrate and aluminum-lithium alloy base material;

[0009] Step S2: Fix the substrate, place the stirring head in the area of ​​the substrate to be added, and adjust the distance between the end face of the stirring head and the substrate.

[0010] Step S3: Load the base material into the hollow stirring head, and set the rotation speed, travel speed of the stirring head and the feeding speed of the aluminum-lithium alloy base material in the program.

[0011] Step S4: Start the program. The stirring head starts to rotate, and the push rod slowly pushes the aluminum-lithium alloy base material to the area to be added. When the aluminum-lithium alloy base material reaches the thermoplastic state, the stirring head starts to advance according to the set program to complete the first layer of deposition.

[0012] Step S5: The stirring head is raised, and the height of the end face of the stirring head relative to the deposition layer is adjusted to perform reverse additive manufacturing, thereby completing the deposition of the second layer of the deposition layer.

[0013] Step S6: Repeat steps S3 to S5, depositing layer by layer upwards until the height of the deposited layer reaches the target height, to obtain a stir-friction deposition additive component;

[0014] Step S7: The stir-friction deposition additive component is first subjected to low-temperature solution treatment and first aging treatment, and then subjected to high-temperature solution treatment and second aging treatment to obtain a high-strength aluminum-lithium alloy.

[0015] Preferably, the aluminum-lithium alloy base material is an Al-Cu-Li alloy.

[0016] Preferably, the diameter of the aluminum-lithium alloy base material is 10-15 mm.

[0017] Preferably, the stirring head rotates at a speed of 380–500 r / min, travels at a speed of 180–220 mm / min, the aluminum-lithium alloy substrate is fed at a speed of 70–100 mm / min, and the interlayer lifting amount is 1–2 mm.

[0018] Preferably, the actual height of the deposition layer in each deposition is 2 to 3 mm.

[0019] Preferably, the low-temperature solution treatment temperature is 400–460°C, and the time is 2–6 hours.

[0020] Preferably, the temperature of the first aging treatment is 165-175°C, and the time is 12-24 hours.

[0021] Preferably, the high-temperature solution treatment temperature is 480–520°C, and the time is 0.5–2 hours.

[0022] Preferably, the temperature of the second aging treatment is 170–175°C, and the time is 24–36 h.

[0023] This application also provides a high-strength aluminum-lithium alloy, which is manufactured using any one of the methods described above.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The high-strength aluminum-lithium alloy friction stir deposition additive manufacturing method provided by the present invention can achieve stable forming of Al-Cu-Li alloy;

[0026] 2. The multi-stage heat treatment method provided by the present invention releases strain energy and forms second-phase particles with pinning effect inside the structure through low-temperature solution treatment and first aging treatment. After high-temperature short-time treatment and second aging treatment, abnormal grain growth is effectively suppressed. Attached Figure Description

[0027] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0028] Figure 1 This is a schematic diagram of the structure manufactured by friction stir deposition additive manufacturing in Example 1;

[0029] Figure 2 This is a macroscopic photograph of the 2195 aluminum-lithium alloy after being formed by friction stir deposition additive manufacturing in Example 1;

[0030] Figure 3 The metallographic structure after low-temperature solution aging and high-temperature solution aging in Example 1;

[0031] Figure 4 The metallographic structure after low-temperature solution treatment followed by high-temperature solution treatment and aging in Comparative Example 1;

[0032] Figure 5 The metallographic structure after high-temperature solution treatment and aging in Comparative Example 2;

[0033] Figure 6 This is a comparison chart of the hardness of the component after multi-stage heat treatment in Example 1 and the hardness of the T8 state 2195 aluminum-lithium alloy base material;

[0034] Figure 7 This is a schematic diagram of the process of friction stir deposition additive manufacturing and multi-stage heat treatment in the embodiment.

[0035] The figure shows: substrate 1, deposited layer 2, stirring head 3, aluminum-lithium alloy base material 4, first forward direction 501, and second forward direction 502. Detailed Implementation

[0036] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0037] This embodiment provides a method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment, such as... Figure 7 As shown, it includes the following steps:

[0038] Step S1: Prepare substrate 1 and aluminum-lithium alloy base material 4;

[0039] Step S2: Fix the substrate 1, place the stirring head 3 in the area of ​​substrate 1 to be added, and adjust the distance between the end face of the stirring head 3 and the substrate.

[0040] Step S3: Load the aluminum-lithium alloy base material 4 into the hollow stirring head 3, and set the rotation speed, travel speed and feeding speed of the stirring head 3 and the aluminum-lithium alloy base material 4 in the program.

[0041] Step S4: Start the program. The stirring head 3 starts to rotate. The push rod slowly pushes the aluminum-lithium alloy base material 4 to the area to be added. When the aluminum-lithium alloy base material 4 reaches the thermoplastic state, the stirring head 3 starts to move forward according to the set program to complete the first layer of deposition.

[0042] Step S5: Raise the stirring head 3, adjust the height of the end face of the stirring head 3 and the deposition layer, perform reverse additive manufacturing, and complete the second deposition layer.

[0043] Step S6: Repeat steps S3 to S5, depositing layer by layer upwards until the height of the deposited layer reaches the target height, to obtain a stir-friction deposition additive component;

[0044] Step S7 involves subjecting the friction-stirred additive manufacturing component to low-temperature solution treatment and a first aging treatment, followed by high-temperature solution treatment and a second aging treatment to obtain a high-strength aluminum-lithium alloy. The low-temperature solution treatment temperature is 400–460℃, and the time is 2–6 hours. The first aging treatment temperature is 165–175℃, and the time is 12–24 hours. Most high-temperature solution treatments are performed at 480–520℃ for 0.5–2 hours. The second aging treatment temperature is 170–175℃, and the time is 24–36 hours.

[0045] In one embodiment, the aluminum-lithium alloy base material is an Al-Cu-Li alloy.

[0046] In one embodiment, the diameter of the aluminum-lithium alloy substrate is 10-15 mm.

[0047] In one embodiment, the stirring head rotates at a speed of 380–500 r / min and travels at a speed of 180–220 mm / min, the aluminum-lithium alloy masterbatch is fed at a speed of 70–100 mm / min, and the interlayer lifting amount is 1–2 mm.

[0048] The interlayer lift is the distance between the end face of the stirring head 3 and the previous deposition layer.

[0049] In one embodiment, the actual height of the deposition layer in each deposition is 2 to 3 mm.

[0050] The high-strength aluminum-lithium alloy friction stir deposition additive manufacturing method provided in this embodiment can achieve stable forming of Al-Cu-Li alloys. Furthermore, the friction stir deposition additive components undergo multi-stage heat treatment. Through low-temperature solution treatment and a first aging treatment, strain-stored energy is released, and second-phase particles with pinning effects are formed within the microstructure. After high-temperature short-time treatment and a second aging treatment, abnormal grain growth is effectively suppressed. This effectively solves the problems of difficult forming and easy cracking of ultra-large and moderately complex aluminum-lithium alloy structural parts, ultimately yielding a high-strength aluminum-lithium alloy.

[0051] Example 1

[0052] like Figure 1 As shown, the aluminum-lithium alloy base material 4 is a T8 state 2195 aluminum-lithium alloy with a diameter of 15mm. The additive manufacturing structural part has dimensions of 45mm×35mm×200mm. The low-temperature solution treatment temperature is 460℃ for 2 hours, the aging temperature is 170℃ for 12 hours, the high-temperature solution treatment temperature is 520℃ for 0.5 hours, and the aging temperature is 175℃ for 36 hours.

[0053] Step S11: First, prepare substrate 1 as an O-state 2219 aluminum alloy substrate with dimensions of 400mm×400mm×25mm. Use 1000# and 2000# sandpaper to polish the surface oxide of substrate 1 clean. Then, wipe the surface of substrate 1 clean with alcohol.

[0054] Step S12: Fix the substrate 1, place the stirring head 3 in the area to be added material, and adjust the distance between the end face of the stirring head 3 and the substrate 1 to 1.5mm.

[0055] Step S13: Load the 2195 aluminum-lithium alloy base material 4 into the hollow stirring head 3 for later use. Set the rotation speed of the stirring head 3 to 430 r / min, the travel speed to 195 mm / min, and the feeding speed to 90 mm / min.

[0056] Step S14: Start the program. The stirring head 3 starts to rotate. The push rod slowly pushes the aluminum-lithium alloy base material 4 to the additive manufacturing area. When the aluminum-lithium alloy base material 4 reaches the thermoplastic state, the stirring head 3 starts to move forward in the set first forward direction 501. The thermoplastic 2195 aluminum alloy material deposits a 2-3 mm deposition layer 2 on the surface of the substrate 1 through stirring friction.

[0057] In step S15, the stirring head 3 is raised and its end face is adjusted to a height of 1.5mm from the first deposited layer. The forward direction is adjusted to the opposite direction of the first forward direction 501 in step S4: the second forward direction 502. According to the set parameters, the thermoplasticized 2195 aluminum alloy material deposits a 2-3mm deposited layer 2 on the surface of the first deposited layer through stirring friction.

[0058] Step S16: Repeat steps S13 to S15 for layer-by-layer deposition until a stir-friction deposition additive component with dimensions of 45mm × 35mm × 200mm is prepared (e.g., Figure 2 (As shown).

[0059] Step S17: After deposition, the substrate and component are separated by wire cutting, and the triboelectric additive component is subjected to multi-stage heat treatment:

[0060] Step S18: The aluminum-lithium alloy after the stir-friction deposition additive manufacturing process in step S16 is first subjected to low-temperature solution treatment and aging, and then subjected to high-temperature solution treatment and aging.

[0061] 1) The 2195 aluminum-lithium alloy components produced by friction stir deposition additive manufacturing were subjected to low-temperature solution treatment at 460℃ for 2 hours. After solution treatment, they were quenched in cold water. Then, the first aging treatment was performed at 170℃ for 12 hours. After aging, the components were cooled in air.

[0062] 2) The components that have undergone low-temperature solution treatment and aging treatment are subjected to high-temperature solution treatment at 520℃ for 0.5h. After the solution treatment is completed, they are quenched in cold water. Then, a second aging treatment is performed at 175℃ for 36h.

[0063] Its microstructure, such as Figure 3 As shown, the grain structure is fine and uniform, and no abnormally large grains are observed.

[0064] like Figure 6As shown, the hardness of the high-strength aluminum-lithium alloy obtained in Example 1 is compared with that of the T8 state 2195 aluminum-lithium alloy base material. The average hardness of the 2195 aluminum-lithium alloy produced by friction stir deposition additive manufacturing after heat treatment reaches 180.7 HV, while the average hardness of the T8 state 2195 aluminum-lithium alloy base material is 190.0 HV. The performance of the T6 state additive manufacturing 2195 aluminum-lithium alloy reaches 95% of that of the base alloy.

[0065] Example 1 solves the problems of difficult forming and easy cracking of ultra-large and medium-complex aluminum-lithium alloy structural parts, and its performance is comparable to that of T8 aluminum-lithium alloy.

[0066] Comparative Example 1

[0067] The base alloy is T8 state 2195 aluminum-lithium alloy with a diameter of 15mm. The additive manufacturing structural part has a size of 45mm×35mm×200mm. The low-temperature solution treatment temperature is 460℃ for 2 hours, the high-temperature solution treatment temperature is 520℃ for 0.5 hours, and the aging temperature is 175℃ for 36 hours.

[0068] Step S21: First, prepare a substrate material of O-state 2219 aluminum alloy with a size of 400mm×400mm×25mm. Use 1000# and 2000# sandpaper to polish the oxide on the substrate surface clean. Then, wipe the substrate surface clean with alcohol.

[0069] Step S22: Fix the substrate, place the stirring head in the area to be added and adjust the distance between its end face and the substrate to 1.5mm;

[0070] Step S23: Load the 2195 aluminum-lithium alloy master material into the hollow stirring head for later use.

[0071] Step S24: Set the rotation speed of the stirring head to 430 r / min, the travel speed to 195 mm / min, and the feeding speed to 90 mm / min.

[0072] Step S25: Start the program. The stirring head starts to rotate. The push rod slowly pushes the aluminum-lithium alloy substrate to the additive manufacturing area. When the aluminum-lithium alloy substrate reaches the thermoplastic state, the stirring head starts to move forward according to the set program. The thermoplastic 2195 aluminum alloy material deposits a 2-3 mm deposition layer on the substrate surface through stirring friction.

[0073] Step S26: Raise the stirring head and adjust its end face to be 1.5mm above the first deposited layer. Adjust the forward direction to the opposite direction. According to the set parameters, the thermoplasticized 2195 aluminum alloy material deposits a 2-3mm layer on the surface of the first deposited layer through stirring and friction. Repeat this step and deposit layer by layer until a component with dimensions of 45mm×35mm×200mm is prepared.

[0074] Step S27: After deposition, the substrate and component are separated by wire cutting, and the friction stir deposition additive component is subjected to multi-stage heat treatment.

[0075] Step S28: The aluminum-lithium alloy after additive manufacturing in step S25 is first subjected to low-temperature solution treatment, and then to high-temperature solution treatment and aging treatment.

[0076] 1) The 2195 aluminum-lithium alloy components produced by friction stir deposition additive manufacturing were subjected to low-temperature solution treatment at a temperature of 460℃ for 2 hours. After the solution treatment was completed, they were quenched in cold water.

[0077] 2) The components that have undergone low-temperature solution treatment are then subjected to high-temperature solution treatment at 520℃ for 0.5 hours, followed by quenching in cold water. Then, aging treatment is performed at 175℃ for 36 hours. The resulting microstructure is as follows: Figure 4 As shown.

[0078] like Figure 4 As shown, Comparative Example 1 exhibits abnormal grain growth, significantly deteriorating the material's strength and toughness. This demonstrates that the multi-stage heat treatment in Example 1 releases stored strain energy, and during the first aging treatment, second-phase particles with grain boundary pinning effects are formed within the grains, effectively suppressing abnormal grain growth during subsequent high-temperature short-time treatment. While Comparative Example 1 relies on low-temperature solution heat treatment to release stored strain energy within the material, the effect is limited, and the lack of grain boundary pinning precipitates within the grains leads to abnormal grain growth during the subsequent high-temperature solution heat treatment stage.

[0079] Comparative Example 2

[0080] The base alloy is T8 state 2195 aluminum-lithium alloy with a diameter of 15mm. The additive manufacturing structural part has a size of 45mm×35mm×200mm. The high-temperature solution treatment temperature is 520℃ and the time is 0.5h; the aging temperature is 175℃ and the time is 36h.

[0081] Step S31: First, prepare a substrate material of O-state 2219 aluminum alloy with a size of 400mm×400mm×25mm. Use 1000# and 2000# sandpaper to polish the oxide on the substrate surface clean. Then, wipe the substrate surface clean with alcohol.

[0082] Step S32: Fix the substrate, place the stirring head in the area to be added and adjust the distance between its end face and the substrate to 1.5mm;

[0083] Step S33: Load the 2195 aluminum-lithium alloy master material into the hollow stirring head for later use;

[0084] Step S34: Set the rotation speed of the stirring head to 430 r / min, the travel speed to 195 mm / min, and the feeding speed to 90 mm / min.

[0085] Step S35: Start the program, the stirring head starts to rotate, and the push rod slowly pushes the aluminum-lithium alloy base material to the additive manufacturing area. When the aluminum-lithium alloy base material reaches the thermoplastic state, the stirring head starts to move forward according to the set program. The thermoplastic 2195 aluminum alloy base material deposits a 2-3 mm deposition layer on the substrate surface through stirring friction.

[0086] Step S36: Raise the stirring head and adjust its end face to be 1.5mm above the first deposited layer. Adjust the forward direction to the opposite direction. According to the set parameters, the thermoplasticized 2195 aluminum alloy material deposits a 2-3mm layer on the surface of the first deposited layer through stirring and friction. Repeat this step and deposit layer by layer until a component with dimensions of 45mm×35mm×200mm is prepared.

[0087] Step S37: After deposition, the substrate and component are separated by wire cutting, and the triboelectric additive component is heat-treated.

[0088] Step S38: Perform high-temperature solution treatment and aging treatment on the aluminum-lithium alloy after additive manufacturing in step S36.

[0089] The 2195 aluminum-lithium alloy component produced by friction stir deposition additive manufacturing was subjected to high-temperature solution treatment at 520℃ for 0.5 hours, followed by quenching in cold water. Then, it underwent aging treatment at 175℃ for 36 hours. Its microstructure is as follows: Figure 5 As shown.

[0090] like Figure 5 As shown, Comparative Example 2 exhibits abnormal grain growth, significantly deteriorating the material's strength and toughness. This demonstrates that the multi-stage heat treatment in Example 1 releases stored strain energy, and during the first aging treatment, second-phase particles with pinning grain boundaries are formed within the grains, effectively suppressing abnormal grain growth during subsequent high-temperature short-time treatment. Because the material undergoes severe plastic deformation during forming, a large number of dislocations and substructures are generated internally, increasing the driving force for grain growth and leading to significant grain enlargement. However, Comparative Example 2 directly performs high-temperature solution treatment on the deposited material, lacking the steps of removing stored strain energy and introducing pinning second-phase particles, ultimately resulting in significant grain growth.

[0091] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0092] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment, characterized in that, include: Step S1: Prepare the substrate (1) and the aluminum-lithium alloy base material (4). Step S2: Fix the substrate (1), place the stirring head (3) in the area of ​​the substrate (1) to be added, and adjust the distance between the end face of the stirring head (3) and the substrate (1). Step S3: The aluminum-lithium alloy master material (4) is loaded into the hollow stirring head (3), and the rotation speed, travel speed and feeding speed of the stirring head (3) and the aluminum-lithium alloy master material (4) are set in the program. Step S4: Start the program. The stirring head (3) starts to rotate. The push rod pushes the aluminum-lithium alloy base material (4) to the area to be added. When the aluminum-lithium alloy base material (4) reaches the thermoplastic state, the stirring head (3) starts to move forward according to the set program to complete the first layer deposition of the deposition layer (2). Step S5: The stirring head (3) is raised, and the height of the end face of the stirring head (3) and the deposition layer is adjusted to perform reverse additive manufacturing and complete the second deposition of the deposition layer (2); Repeat steps S3 to S5, depositing layer by layer upwards until the height of the deposition layer (2) reaches the target height, to obtain a stir-friction deposition additive component; Step S6: The stir-friction deposition additive component is first subjected to low-temperature solution treatment and first aging treatment, and then subjected to high-temperature solution treatment and second aging treatment to obtain a high-strength aluminum-lithium alloy.

2. The method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to claim 1, characterized in that, The aluminum-lithium alloy base material (4) is an Al-Cu-Li alloy.

3. The method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to claim 1, characterized in that, The diameter of the aluminum-lithium alloy base material (4) is 10-15 mm.

4. The method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to claim 1, characterized in that, The stirring head (3) has a rotation speed of 380-500 r / min and a travel speed of 180-220 mm / min. The aluminum-lithium alloy mother material (4) has a feeding speed of 70-100 mm / min and an interlayer lifting amount of 1-2 mm.

5. The method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to claim 1, characterized in that, The actual height of the deposition layer in each deposition is 2 to 3 mm.

6. The method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to claim 1, characterized in that, The low-temperature solution treatment temperature is 400–460℃, and the time is 2–6 hours.

7. The method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to claim 1, characterized in that, The temperature for the first aging treatment is 165–175°C, and the time is 12–24 hours.

8. The method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to claim 1, characterized in that, Most high-temperature solution treatments are carried out at temperatures ranging from 480 to 520°C for 0.5 to 2 hours.

9. The method for high-strength aluminum-lithium alloy friction stir deposition additive manufacturing and multi-stage heat treatment according to claim 1, characterized in that, The second aging treatment is performed at a temperature of 170–175°C for 24–36 hours.

10. A high-strength aluminum-lithium alloy, characterized in that, It is made using the method described in any one of claims 1 to 9.

Images