Deformation-induced twin-crystal aluminum-magnesium alloy composite material and preparation method thereof

Abstract

The invention relates to the technical field of aluminum alloy materials, in particular to a deformation-induced twin-crystal aluminum-magnesium alloy composite material and a preparation method thereof. The composite material is an Hf2PbC particle reinforced Al-Mg alloy composite material, the content of Mg in an Al-Mg alloy is 2.0-6.5 wt%, and the balance is Al; the size of Hf2PbC particles is 10 microns, and the addition amount of the Hf2PbC particles accounts for 0.05-1.0% of the total mass of the composite material According to the method, the spark plasma sintering technology is adopted for preparation, the Hf2PbC ceramic particles serve as a high-melting-point and high-hardness strengthening phase, particle composite strengthening can be achieved, and the Al-Mg alloy strength and hardness level of the material can be improved. High-pressure torsion and a Hopkinson bar dynamic loading technology are organically combined, the synergistic effect of large-plasticity shearing and high-strain-rate compression is achieved, continuous activation of a multi-scale deformation mechanism can be triggered in the aluminum magnesium alloy, and nucleation and expansion of high-density deformation twin crystals are effectively promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum alloy materials, and more specifically, to a deformation-induced twinned aluminum-magnesium alloy composite material and a preparation method thereof. Background Art

[0002] Aluminum-magnesium alloys have broad application prospects in transportation, aerospace, and military industries due to their light weight, high specific strength, good corrosion resistance, and weldability. However, the mechanical properties of traditional aluminum-magnesium alloys are still significantly insufficient, and their strength and plasticity are often difficult to improve simultaneously, limiting their application in scenarios with higher performance requirements. To improve the strength of the alloy, researchers usually achieve composite strengthening by adding second-phase strengthening particles (such as ceramic particles or intermetallic compounds). However, this method often leads to a significant decrease in plasticity while increasing hardness, affecting the material's forming ability and service reliability.

[0003] Recent research on nanostructured materials has demonstrated that the introduction of twin boundaries can simultaneously optimize both strength and plasticity. Twin boundaries can act as dislocation sources to promote plastic deformation while also hindering dislocation motion, thereby improving the material's strength-toughness balance. However, aluminum and its alloys, typical materials with high stacking fault energy, are subject to dislocation slip during conventional plastic deformation, making it difficult to spontaneously form deformation twins. This significantly limits the application of twinning strengthening mechanisms in aluminum alloys. Although small amounts of twins can be induced in aluminum through severe plastic deformation (such as equal-channel angular pressing and high-pressure torsion) or extreme conditions (such as low-temperature deformation and high strain rate loading), the process is complex and difficult to scale up. Therefore, developing novel processing technologies to promote the formation of deformation twins in aluminum-magnesium alloys under controllable conditions, thereby overcoming the limitations of traditional strengthening mechanisms and achieving a synergistic improvement in strength and plasticity, has become a key scientific issue that needs to be addressed urgently in this field and is of great significance for promoting the engineering application of high-performance aluminum-magnesium alloys. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one aspect of the present invention is to provide a deformation-induced twinned aluminum-magnesium alloy composite material, wherein the composite material is an Hf2PbC particle-reinforced Al-Mg alloy composite material, and the Al-Mg alloy components are as follows: Mg content is 2.0wt% to 6.5wt%, and the rest is Al; the Hf2PbC particles have a size of 10μm, and their addition amount accounts for 0.05% to 1.0% of the total mass of the composite material.

[0005] Another aspect of the present invention is to provide a method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material, wherein the preparation method comprises the following steps: S1. Preparation of Al-Mg alloy spherical powder: Prepare the raw materials with a Mg content of 2.0wt% to 6.5wt% by mass, with the remainder being Al. Smelt the melt to a qualified composition using an induction melting device while maintaining a superheated state. The melt is then sprayed into an atomizing disk. Under the centrifugal action of the high-speed rotation of the atomizing disk, molten droplets are ejected and fly within the atomizing chamber, where they cool and solidify to form powder. S2. Preparation of Hf2PbC particle-reinforced Al-Mg alloy composite powder: Al-Mg alloy powder with a particle size of less than 10 μm was screened out. Hf2PbC powder with a particle size of approximately 10 μm was then selected. The Hf2PbC powder was added in an amount of 0.05% to 1.0% of the total mass. Both powders were placed in a WC ball mill, a dispersant was added, and the mixture was ball milled using WC grinding balls. S3 sintering Hf2PbC particle reinforced Al-Mg alloy composite block: The Hf2PbC particle reinforced powder prepared in S2 was placed in a plasma spark sintering furnace for spark plasma hot pressing sintering; S4 processed Hf2PbC particle reinforced Al-Mg alloy composite material original sheet sample: the material prepared in S3 by wire cutting into a disc sample; S5. High-pressure torsion treatment: The disc-shaped specimen cut in S4 is placed between the upper and lower molds of a high-pressure torsion apparatus, ensuring that the specimen is centered and fits tightly against the molds. An axial preload is first applied, followed by a pre-torsion at a constant rotational speed. The axial pressure is then increased and maintained constant, while the main torsion is continued at this high-pressure speed, causing the specimen to undergo severe plastic shear deformation and gradually reduce its thickness. S6. Dynamic loading of a Hopkinson bar: The sample, after the S5 high-pressure torsion treatment, is placed in a Hopkinson bar experimental apparatus and clamped between the incident and transmitted bars. A high axial strain rate impact load is applied to the sample. Through multiple dynamic deformations, the sample thickness is further reduced, achieving plastic compression deformation, thereby inducing the formation of an ultrafine twin structure.

[0006] Preferably, the superheat in S1 is 50° C.-150° C., and the melt is sprayed into the atomizing disk at a flow rate of 40 kg / h-100 kg / h.

[0007] Preferably, the diameter of the atomizing disk in S1 is 100 mm, the rotation speed is 30,000-80,000 r / min, and the atomizing chamber is filled with Ar protective gas.

[0008] Preferably, the dispersant in S2 is stearic acid powder.

[0009] Preferably, the WC grinding balls in S2 have a particle size of 3 mm to 16 mm and are subjected to ball milling treatment; the ball milling speed is 350 to 450 rpm, the ball-to-material ratio is (15 to 20):1, the ball milling time is 10 h to 20 h, and Ar protection is introduced throughout the ball milling process.

[0010] Preferably, the sintering temperature in S3 is in the range of 350° C. to 450° C., the sintering pressure is 50 MPa, and the holding time is 5 min to 10 min.

[0011] Preferably, in said S4, the material prepared in S3 is processed by wire cutting into a disc-shaped sample with a diameter of 20 mm and a thickness of 4 mm.

[0012] Preferably, in S5, an axial preload of 2 GPa is first applied, and a pre-twist is applied for 2 turns at a constant speed of 0.5 rpm; then the axial pressure is increased to 4 GPa to 6 GPa, and the constant pressure is maintained, and the main twist is continued to be applied for 10 turns at a speed of 0.8 rpm under this high-pressure state, so that the sample undergoes severe plastic shear deformation and the thickness is gradually thinned to about 2 mm.

[0013] Preferably, in the S6, the driving pressure of the incident rod is adjusted to 0.35MPa to 0.55MPa, the deformation temperature is controlled between -196℃ and room temperature, and the corresponding strain rate range is 1500s⁻¹ to 3000s⁻¹. Through multiple dynamic deformations, the thickness of the sample is further reduced to 1mm, and the corresponding axial true strain is 0.693, achieving a plastic compression deformation of about 50%. The beneficial effects of the present invention are as follows: 1. The present invention adopts spark plasma sintering (SPS) technology to prepare Hf2PbC particle reinforced Al-Mg alloy composite material. Hf2PbC ceramic particles serve as a reinforcing phase with high melting point and high hardness, which can realize particle composite reinforcement and improve the strength and hardness level of the Al-Mg alloy material.

[0014] 2. In the present invention, the Mg content is precisely controlled within the mass percentage range of 2.0 wt% to 6.5 wt%, so that Mg is distributed in the aluminum matrix in the form of solid solution, effectively controlling the degree of lattice distortion and reducing the stacking fault energy of aluminum (according to relevant theoretical estimates, the stacking fault energy of pure Al is about 150 mJ / m 2 After adding 6.5 wt% Mg, the stacking fault energy is about 60mJ / m 2 ), promoting the nucleation and expansion of twins under severe plastic deformation conditions. At the same time, it avoids the precipitation of brittle secondary phases such as Al3Mg2 under high Mg content conditions, helps maintain grain boundary integrity and twin boundary stability, and ultimately obtains an aluminum-magnesium alloy with a high-density ultrafine twin structure, balancing strength and plasticity.

[0015] 3. This invention combines high-pressure torsion (HPT) with dynamic loading using a Hopkinson bar (SHPB) technique, achieving a synergistic effect of high plastic shear and high strain-rate compression. This method can trigger the continuous activation of multi-scale deformation mechanisms in aluminum-magnesium alloys, effectively promoting the nucleation and expansion of high-density deformation twins. During HPT, the combined effects of high pressure and torsion on the material lead to grain refinement, forming ultrafine-grained or even nanocrystalline structures. This provides the material with an initial uniform, refined microstructure and high dislocation density. This method is commonly used to improve the strength, hardness, and other mechanical properties of materials while maintaining good ductility. This provides a structural foundation for subsequent twin nucleation, while the Hopkinson bar loading, under high strain rates and dynamic stress conditions, further drives the formation of large numbers of twins, enhancing microstructure density and interfacial stability. This combination not only increases the quantity and quality of deformation twins but also overcomes the limitations of a single deformation method, significantly improving the material's overall mechanical properties and microstructural control capabilities.

[0016] Additional aspects and advantages of the invention will become apparent from the description which follows, or may be learned by practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which: Figure 1 It is a schematic diagram of the high-pressure torsion process; Figure 2 This is a schematic diagram of the organizational transformation during high-pressure torsion; Figure 3 This is a picture of Example 1 of the present invention after 0.05wt% Hf2PbC / Al-5.5Mg plasma hot pressing (SPS); Figure 4 This is a TEM image of twins in a 0.05wt% Hf2PbC / Al-5.5Mg matrix according to Example 1 of the present invention. DETAILED DESCRIPTION

[0018] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0019] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from the description. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0020] like Figure 1 and 2As shown, the high-pressure torsion process gradually achieves grain refinement through a series of processes: dislocation accumulation → subgrain formation → grain boundary evolution. Therefore, high-pressure torsion provides the material with an initial uniform and refined structure. According to grain refinement strengthening theory, smaller grain size is more conducive to strength, hardness, and maintaining good ductility, providing a structural foundation for subsequent twin nucleation.

[0021] If the material has not undergone high-pressure torsion, the original grains are relatively coarse, and the grain size is closely related to the material's plastic deformation capacity. When the grains are coarse, the grain boundary area is reduced, and the grain boundary's barrier to dislocation movement is reduced, resulting in a decrease in the material's overall plasticity. At the same time, the stress distribution within the coarse-grained material is extremely uneven, making stress concentration more likely to form in local areas, increasing the probability of crack initiation and propagation. During the rapid deformation of the Hopkinson bar, this stress concentration effect is further exacerbated, inducing the rapid propagation of brittle cracks, ultimately leading to premature cracking or even fracture of the specimen. Therefore, coarse-grained materials exhibit more obvious brittle characteristics in the Hopkinson bar test, and the cracking tendency is significantly increased. Therefore, it is necessary to refine the grains after high-pressure torsion before conducting the Hopkinson bar rapid deformation test.

[0022] After high-pressure torsion, the grain size of the Hf2PbC particle-reinforced Al-Mg alloy composite material is reduced to a few dozen microns. The addition of an appropriate amount of Mg to the matrix significantly reduces the stacking fault energy of the matrix, which in turn facilitates the initiation of a twinning deformation mechanism. During the rapid deformation of the Hopkinson bar, under high strain rate loading, dislocation motion and slip within the material are restricted, leading to a rapid increase in local shear stress, which in turn favors the material's plastic deformation through the twinning mechanism. During high-speed impact, the probability of internal stress exceeding the critical shear stress for twinning increases significantly, triggering the activation of the crystal twinning mechanism. Furthermore, the local stress waves induced by high-speed deformation propagate rapidly within the grains, causing strong local strain concentrations that intensify the nucleation and rapid expansion of twins, ultimately forming a twinned structure.

[0023] Example 1 Preparation of Al-Mg alloy spherical powder: Prepare the raw materials according to the mass percentage: Mg content is 5.5wt%, and the rest is Al. The raw materials are prepared in the composition ratio. The melt with qualified composition is melted by induction melting device and maintained at 100°C superheat. The melt is then sprayed into the atomizing disk at a flow rate of 50 kg / h. Under the centrifugal effect of the high-speed rotation of the atomizing disk, the molten droplets are ejected and fly in the atomizing chamber, cool, and solidify to form powder. The atomizing disk has a diameter of 100 mm and a rotation speed of 55,000 r / min. The atomizing chamber is filled with Ar protective gas. Preparation of Hf2PbC particle-reinforced Al-Mg alloy composite powder: Al-Mg alloy powder with a particle size of less than 10 μm was screened out, and then Hf2PbC powder with a particle size of about 10 μm was selected and added in an amount of 0.05% of the total mass. Both powders were placed in a WC ball mill, and stearic acid powder was added as a dispersant. WC grinding balls with a particle size of 3 mm to 16 mm were used for ball milling at a ball milling speed of 400 rpm, a ball-to-powder ratio of 20:1, and a ball milling time of 15 h. Ar protection was introduced throughout the ball milling process. Sintering Hf2PbC particle reinforced Al-Mg alloy composite block: The prepared Hf2PbC particle reinforced powder was placed in a plasma spark sintering furnace for spark plasma hot pressing sintering at a sintering temperature of 380°C, a sintering pressure of 50 MPa, and a holding time of 5 min. Processing Hf2PbC particle reinforced Al-Mg alloy composite material original sheet samples: The prepared material was processed into circular sheet samples with a diameter of 20mm and a thickness of 4mm by wire cutting. Both sides of the sample were mechanically polished to ensure the surface flatness; High-pressure torsion treatment: The disc-shaped specimen is placed in a high-pressure torsion die system, centered, and clamped. An axial preload of 2 GPa is first applied, followed by two pre-twisting cycles at 0.5 rpm to activate dislocations and initial microdeformation mechanisms. The axial pressure is then increased to 5 GPa and maintained constant. Under these conditions, the main torsion cycle is continued at 0.8 rpm for 10 cycles. During this process, the specimen thickness gradually decreases from 4 mm to approximately 2 mm, forming a high-density dislocation structure and refined grains.

[0024] Dynamic Hopkinson bar loading: The sample, after high-pressure torsion treatment, was clamped between the incident and transmission rods of a 14mm high-strength steel Hopkinson bar device, using insulating tape for positioning. The device's driving air pressure was set to 0.45 MPa, and the initial loading velocity was approximately 20 m / s. The deformation temperature was controlled at room temperature, and the corresponding strain rate during the deformation process was approximately 2200 s⁻¹. After a single loading cycle, the sample thickness was compressed from 2 mm to 1 mm, with an axial true strain of 0.693, indicating sufficient plastic compression deformation.

[0025] The deformed sample was observed by transmission electron microscopy (TEM), and deformation twin structures were clearly observed inside the grains, which verified the effectiveness of the method of the present invention in forming twin structures. Figure 3 (Image of 0.05wt% Hf2PbC / Al-5.5Mg after plasma hot pressing (SPS)) and Figure 4As shown in the TEM image of twins in a 0.05wt% Hf2PbC / Al-5.5Mg matrix, the twins exhibit distinct twinning characteristics, appearing as a series of straight, regularly arranged thin stripes that extend across the grain interior. The twin interfaces are distinct. The 0.05wt% Hf2PbC / Al-5.5Mg matrix is made of an Al-5.5Mg alloy. The addition of Mg reduces the stacking fault energy of the matrix. Under high-speed impact loading from a Hopkinson bar, rapid deformation triggers the twinning mechanism, inducing the formation of a twinned structure.

[0026] Example 2 Preparation of Al-Mg alloy spherical powder: Prepare the raw materials according to the mass percentage: Mg content is 4.0wt%, and the rest is Al. The raw materials are prepared in the composition ratio. The melt with qualified composition is melted by induction melting device and maintained at 80°C superheat. The melt is then sprayed into the atomizing disk at a flow rate of 50kg / h. Under the centrifugal effect of the high-speed rotation of the atomizing disk, the molten droplets are ejected and fly in the atomizing chamber, cool, and solidify to form powder. The atomizing disk has a diameter of 100mm and a rotation speed of 55000r / min. The atomizing chamber is filled with Ar protective gas. Preparation of Hf2PbC particle-reinforced Al-Mg alloy composite powder: Al-Mg alloy powder with a particle size of less than 10 μm was screened out, and then Hf2PbC powder with a particle size of about 10 μm was selected and added in an amount of 0.1% of the total mass. Both powders were placed in a WC ball mill, and stearic acid powder was added as a dispersant. WC grinding balls with a particle size of 3 mm to 16 mm were used for ball milling at a ball milling speed of 400 rpm, a ball-to-powder ratio of 15:1, and a ball milling time of 15 h. Ar protection was introduced throughout the ball milling process. Sintering Hf2PbC particle reinforced Al-Mg alloy composite block: The prepared Hf2PbC particle reinforced powder was placed in a plasma spark sintering furnace for spark plasma hot pressing sintering at a sintering temperature of 380°C, a sintering pressure of 50 MPa, and a holding time of 5 min. Processing Hf2PbC particle reinforced Al-Mg alloy composite material original sheet samples: The prepared material was processed into circular sheet samples with a diameter of 20mm and a thickness of 4mm by wire cutting. Both sides of the sample were mechanically polished to ensure the surface flatness; High-pressure torsion treatment: The disc-shaped specimen is placed in a high-pressure torsion die system, centered, and clamped. An axial preload of 2 GPa is first applied, followed by two pre-twisting cycles at 0.5 rpm to activate dislocations and initial microdeformation mechanisms. The axial pressure is then increased to 4 GPa and maintained constant. Under these conditions, the main torsion cycle is continued at 0.8 rpm for 10 cycles. During this process, the specimen thickness gradually decreases from 4 mm to approximately 2 mm, forming a high-density dislocation structure and refined grains.

[0027] Dynamic Hopkinson bar loading: The sample, after high-pressure torsion treatment, was clamped between the incident and transmission rods of a 14mm high-strength steel Hopkinson bar device, using insulating tape for positioning. The device's driving air pressure was set to 0.45 MPa, and the initial loading velocity was approximately 20 m / s. The deformation temperature was controlled at room temperature, and the corresponding strain rate during the deformation process was approximately 2200 s⁻¹. After a single loading cycle, the sample thickness was compressed from 2 mm to 1 mm, with an axial true strain of 0.693, indicating sufficient plastic compression deformation.

[0028] The deformed sample was observed through a transmission electron microscope (TEM), and deformation twin structures were clearly observed inside the grains, verifying the effectiveness of the method of the present invention in forming twin structures.

[0029] Example 3 Preparation of Al-Mg alloy spherical powder: Prepare the raw materials according to the mass percentage: Mg content is 4.5wt%, and the rest is Al. The raw materials are prepared in the composition ratio. The melt with qualified composition is melted by induction melting device and maintained at 70°C superheat. The melt is then sprayed into the atomizing disk at a flow rate of 50 kg / h. Under the centrifugal effect of the high-speed rotation of the atomizing disk, the molten droplets are ejected and fly in the atomizing chamber, cool, and solidify to form powder. The atomizing disk has a diameter of 100 mm and a rotation speed of 55,000 r / min. The atomizing chamber is filled with Ar protective gas. Preparation of Hf2PbC particle-reinforced Al-Mg alloy composite powder: Al-Mg alloy powder with a particle size of less than 10 μm was screened out, and then Hf2PbC powder with a particle size of about 10 μm was selected and added in an amount of 0.2% of the total mass. Both powders were placed in a WC ball mill, and stearic acid powder was added as a dispersant. WC grinding balls with a particle size of 3 mm to 16 mm were used for ball milling at a ball milling speed of 400 rpm, a ball-to-powder ratio of 15:1, and a ball milling time of 15 h. Ar protection was introduced throughout the ball milling process. Sintering Hf2PbC particle reinforced Al-Mg alloy composite block: The prepared Hf2PbC particle reinforced powder was placed in a plasma spark sintering furnace for spark plasma hot pressing sintering at a sintering temperature of 380°C, a sintering pressure of 50 MPa, and a holding time of 5 min. Processing Hf2PbC particle reinforced Al-Mg alloy composite material original sheet samples: The prepared material was processed into circular sheet samples with a diameter of 20mm and a thickness of 4mm by wire cutting. Both sides of the sample were mechanically polished to ensure the surface flatness; High-pressure torsion treatment: The disc-shaped specimen is placed in a high-pressure torsion die system, centered, and clamped. An axial preload of 2 GPa is first applied, followed by two pre-twisting cycles at 0.5 rpm to activate dislocations and initial microdeformation mechanisms. The axial pressure is then increased to 5 GPa and maintained constant. Under these conditions, the main torsion cycle is continued at 0.8 rpm for 10 cycles. During this process, the specimen thickness gradually decreases from 4 mm to approximately 2 mm, forming a high-density dislocation structure and refined grains.

[0030] Dynamic Hopkinson bar loading: The sample, after high-pressure torsion treatment, was clamped between the incident and transmission rods of a 14mm high-strength steel Hopkinson bar device, using insulating tape for positioning. The device's driving air pressure was set to 0.45 MPa, and the initial loading velocity was approximately 20 m / s. The deformation temperature was controlled at room temperature, and the corresponding strain rate during the deformation process was approximately 2200 s⁻¹. After a single loading cycle, the sample thickness was compressed from 2 mm to 1 mm, with an axial true strain of 0.693, indicating sufficient plastic compression deformation.

[0031] The deformed sample was observed through a transmission electron microscope (TEM), and deformation twin structures were clearly observed inside the grains, verifying the effectiveness of the method of the present invention in forming twin structures.

[0032] The embodiments of the present invention show that by combining high-pressure torsion with the dynamic loading method of the Hopkinson bar, it is possible to construct an ultrafine twin structure in an aluminum-magnesium alloy, significantly improving the material's organizational uniformity and mechanical properties, verifying the feasibility and superiority of the present invention.

[0033] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A deformation-induced twinned aluminum-magnesium alloy composite material, characterized by: The composite material is an Hf2PbC particle reinforced Al-Mg alloy composite material. The Al-Mg alloy components are as follows: Mg content is 2.0wt% to 6.5wt% by mass, and the rest is Al; the Hf2PbC particles have a size of 10 μm, and their addition amount accounts for 0.05% to 1.0% of the total mass of the composite material.

2. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 1, characterized in that: The specific steps of the preparation method are as follows: S1. Preparation of Al-Mg alloy spherical powder: Prepare the raw materials with a Mg content of 2.0wt% to 6.5wt% by mass, with the remainder being Al. Smelt the melt to a qualified composition using an induction melting device while maintaining a superheated state. The melt is then sprayed into an atomizing disk. Under the centrifugal action of the high-speed rotation of the atomizing disk, molten droplets are ejected and fly within the atomizing chamber, where they cool and solidify to form powder. S2. Preparation of Hf2PbC particle-reinforced Al-Mg alloy composite powder: Al-Mg alloy powder with a particle size of less than 10 μm was screened out. Hf2PbC powder with a particle size of approximately 10 μm was then selected. The Hf2PbC powder was added in an amount of 0.05% to 1.0% of the total mass. Both powders were placed in a WC ball mill, a dispersant was added, and the mixture was ball milled using WC grinding balls. S3 sintering Hf2PbC particle reinforced Al-Mg alloy composite block: The Hf2PbC particle reinforced powder prepared in S2 was placed in a plasma spark sintering furnace for spark plasma hot pressing sintering; S4 processed Hf2PbC particle reinforced Al-Mg alloy composite material original sheet sample: the material prepared in S3 by wire cutting into a disc sample; S5. High-pressure torsion treatment: The disc-shaped specimen cut in S4 is placed between the upper and lower molds of a high-pressure torsion apparatus, ensuring that the specimen is centered and fits tightly against the molds. An axial preload is first applied, followed by a pre-torsion at a constant rotational speed. The axial pressure is then increased and maintained constant, while the main torsion is continued at this high-pressure speed, causing the specimen to undergo severe plastic shear deformation and gradually reduce its thickness. S6. Dynamic loading of a Hopkinson bar: The sample, after the S5 high-pressure torsion treatment, is placed in a Hopkinson bar experimental apparatus and clamped between the incident and transmitted bars. A high axial strain rate impact load is applied to the sample. Through multiple dynamic deformations, the sample thickness is further reduced, achieving plastic compression deformation, thereby inducing the formation of an ultrafine twin structure.

3. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 2, characterized in that: The superheat degree in S1 is 50° C.-150° C., and the melt is sprayed into the atomizing disk at a flow rate of 40 kg / h-100 kg / h.

4. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 2, characterized in that: The diameter of the atomizing disk in S1 is 100 mm, the rotation speed is 30,000-80,000 r / min, and the atomizing chamber is filled with Ar protective gas.

5. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 2, characterized in that: The dispersant in S2 is stearic acid powder.

6. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 2, characterized in that: The WC grinding balls in the S2 have a particle size of 3 mm to 16 mm and are subjected to ball milling. The ball milling speed is 350 to 450 rpm, the ball-to-material ratio is (15 to 20):1, the ball milling time is 10 h to 20 h, and Ar protection is introduced throughout the ball milling process.

7. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 2, characterized in that: The sintering temperature range in S3 is 350° C. to 450° C., the sintering pressure is 50 MPa, and the holding time is 5 min to 10 min.

8. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 2, characterized in that: In the S4, the material prepared in S3 is processed by wire cutting into a disc-shaped sample with a diameter of 20 mm and a thickness of 4 mm.

9. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 2, characterized in that: In the S5, an axial preload of 2 GPa is first applied, and a pre-twist is applied for 2 turns at a constant speed of 0.5 rpm. Then, the axial pressure is increased to 4 GPa to 6 GPa and the constant pressure is maintained. Under this high-pressure state, the main twist is continued to be applied for 10 turns at a speed of 0.8 rpm, causing the sample to undergo severe plastic shear deformation and gradually thinning the thickness to about 2 mm.

10. The method for preparing a deformation-induced twinned aluminum-magnesium alloy composite material according to claim 2, characterized in that: In the S6, the driving air pressure of the incident rod is adjusted to 0.35 MPa to 0.55 MPa, the deformation temperature is controlled between -196 ° C and room temperature, and the corresponding strain rate range is 1500 s⁻¹ to 3000 s⁻¹. Through multiple dynamic deformations, the sample thickness is further reduced to 1 mm, and the corresponding axial true strain is 0.693, achieving a plastic compression deformation of about 50%.

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