High-performance magnesium-lithium alloy material and preparation method thereof

Abstract

The application discloses a kind of high-performance magnesium-lithium alloy materials, the high-performance magnesium-lithium alloy material is obtained by being compacted by magnesium-lithium alloy powder into mould, then sintering densification is carried out, in addition, the application also provides a kind of preparation method of high-performance magnesium-lithium alloy material, comprising the following steps: one, Mg-8Li-9Al-1Zn alloy powder is weighed and loaded into mould;Two, the powder in the powder loaded mould is compacted;Three, the mould with compacted powder is sintered densification in vacuum, and high-performance magnesium-lithium alloy material is obtained in mould.The high-performance magnesium-lithium alloy material of the application uses Mg-8Li-9Al-1Zn alloy powder as raw material, is compacted by being loaded into mould, then sintering densification is carried out, process flow is short, cost is low, operation is simple, flexible, the obtained high-performance magnesium-lithium alloy material component is uniform, organization is small, and the organization, structure of material can be designed, easily controlled, and the compressive strength is greater than 500MPa.

Description

Technical Field

[0001] This invention belongs to the technical field of high-performance magnesium-lithium alloy materials, specifically relating to a high-performance magnesium-lithium alloy material and its preparation method. Background Technology

[0002] Entering the 21st century, my country's aerospace industry has achieved a qualitative leap. From the Chang'e lunar exploration program and the BeiDou navigation system to the Tianwen-Mars mission and the Tiangong space station, we have forged a path in space exploration. Following development trends, the functional and performance requirements of ultra-high power and large payload spacecraft are constantly increasing. This necessitates the rapid development of aerospace materials and their fabrication technologies towards lightweight, high-performance, multifunctional, and high-quality materials. Therefore, there is an urgent need to develop materials that are lightweight, high-strength, and possess excellent comprehensive performance.

[0003] Magnesium-lithium alloys are the lightest magnesium alloys and currently the lightest structural metals. Typical magnesium alloys have a density of only 1.3 g / cm³. 3 ~1.9g / cm 3 It is only 2 / 3 the weight of aluminum alloy and 1 / 5 the weight of steel, while the lightest magnesium-lithium alloy can reach 0.95 g / cm³. 3 Magnesium-lithium alloys, similar to plastics, can float on water. Replacing aluminum alloys with magnesium-lithium alloys can achieve a weight reduction of 40%–50%, thereby improving the performance of aerospace components and meeting my country's demand for high thrust-to-weight ratio spacecraft. Simultaneously, magnesium-lithium alloys combine the advantages of magnesium alloys, such as high specific strength, high specific stiffness, low density, good electromagnetic shielding performance, and high damping performance. They are also excellent functional materials and have already been preliminarily applied to non-load-bearing structures such as deep-space structural components and small satellite electronic structural components in my country.

[0004] However, the magnesium-lithium alloy materials currently in use are mostly relatively mature grades developed by the United States and the Soviet Union in the 1970s and 1980s. Therefore, it is necessary to develop magnesium-lithium alloy materials with independent intellectual property rights in my country. Furthermore, although magnesium-lithium alloy materials are lightweight and possess a range of functional properties, their absolute strength is low, making them unsuitable for use as primary load-bearing components in critical parts. Therefore, there is an urgent need to develop magnesium-lithium alloy materials with high mechanical properties.

[0005] Currently, magnesium-lithium alloy materials are mainly prepared through vacuum melting. However, due to the easy oxidation and volatility of magnesium and lithium, the melting process presents significant challenges. Furthermore, magnesium-lithium alloy materials prepared by melting often exhibit coarse microstructures and severe component segregation, which seriously affect their mechanical properties. Therefore, there is an urgent need to explore advanced preparation technologies.

[0006] With the development of powder metallurgy technology and the maturity of alloy powder preparation processes, the preparation of materials through powder metallurgy has unparalleled advantages over casting methods. Among them, spark plasma sintering (SPS), as a novel powder metallurgy sintering technology, has advantages such as uniform heating, rapid heating rate, low sintering temperature, short sintering time, high production efficiency, energy saving, and environmental protection. Moreover, this process has a short flow, simple operation, and high efficiency in material preparation; at the same time, the resulting materials have fine microstructure and uniform composition, and their composition and structure can be designed and easily controlled.

[0007] Therefore, a method for preparing magnesium-lithium alloy materials by spark plasma sintering is needed to achieve a short-process, efficient preparation of high-performance magnesium-lithium alloy materials. Summary of the Invention

[0008] The technical problem to be solved by this invention is to provide a high-performance magnesium-lithium alloy material, addressing the shortcomings of the prior art. This high-performance magnesium-lithium alloy material is obtained by using magnesium-lithium alloy powder as raw material, which is compacted in a mold and then sintered to achieve densification. The resulting high-performance magnesium-lithium alloy material has uniform composition, fine microstructure, and its microstructure and structure can be designed and easily controlled, with a compressive strength greater than 500 MPa.

[0009] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a high-performance magnesium-lithium alloy material, characterized in that the high-performance magnesium-lithium alloy material is obtained by loading magnesium-lithium alloy powder into a mold, compacting it, and then sintering and densifying it.

[0010] This invention uses magnesium-lithium alloy powder as raw material and employs powder metallurgy to prepare high-performance magnesium-lithium alloy materials. The process is simple and flexible, and the resulting high-performance magnesium-lithium alloy materials have advantages such as fine grains, uniform composition, and easily controllable microstructure. In addition, the powder metallurgy method can achieve near-net-shape forming, high material utilization, and low preparation cost.

[0011] The aforementioned high-performance magnesium-lithium alloy material is characterized in that the magnesium-lithium alloy powder is prepared by gas atomization, the particle size of the magnesium-lithium alloy powder is -100 mesh to -325 mesh, and the morphology is spherical or near-spherical. The composition of the magnesium-lithium alloy powder is Mg-8Li-9Al-1Zn. In this invention, the Mg-8Li-9Al-1Zn alloy has low density and high specific strength. Furthermore, this alloy belongs to a dual-phase (α+β) magnesium-lithium alloy, exhibiting good plastic deformation capability, and can be further strengthened through plastic deformation.

[0012] In this invention, Mg-8Li-9Al-1Zn represents 8% by mass of Li, 9% by mass of Al, 1% by mass of Zn, and the balance being Mg.

[0013] In addition, the present invention provides a method for preparing high-performance magnesium-lithium alloy materials, characterized in that the method includes the following steps:

[0014] Step 1: Weigh out Mg-8Li-9Al-1Zn alloy powder, then put it into the mold, and then vibrate the mold to spread the powder evenly inside the mold to obtain the powder filling mold.

[0015] Step 2: Compact the powder in the powder-filling mold obtained in Step 1 using the upper and lower pressure heads of the mold to obtain a mold containing compacted powder.

[0016] Step 3: The mold containing the compacted powder obtained in Step 2 is vacuum sintered and densified to obtain a high-performance magnesium-lithium alloy material in the mold.

[0017] The above method is characterized in that the mold in step one is a graphite mold or a steel mold. In this invention, the graphite mold has low processing, preparation, and use costs, is easy to operate, and is resistant to high temperatures, but it is easily worn out and has limited pressure resistance, thus affecting the density of the final sintered sample. In contrast, the steel mold is sturdy and durable, can withstand higher pressure, and therefore can obtain materials that fully achieve the theoretical density, which is beneficial for obtaining high-performance materials. However, it is not resistant to high temperatures, is cumbersome to operate, and has high processing costs. Therefore, both types of molds have their advantages and can be selected according to actual needs.

[0018] The above method is characterized in that, if a graphite mold is used, the pressure for vacuum sintering densification is 10 MPa to 40 MPa; if a steel mold is used, the pressure for vacuum sintering densification is 40 MPa to 100 MPa. In this invention, a suitable pressure is selected based on the appropriate mold, because excessively low pressure is detrimental to the densification of the alloy powder and affects the sintering quality, while excessively high pressure poses safety hazards to both the mold and the equipment.

[0019] The above method is characterized in that the vacuum sintering densification in step three is replaced by spark plasma sintering. The spark plasma sintering process is as follows: a mold containing compacted powder is placed in a spark plasma sintering furnace and pressurized and evacuated. The mold is heated to 15°C to 50°C below the holding temperature at a heating rate of 15°C to 35°C / min and a heating power of 15% to 30%. The temperature is then held for 1 to 2 minutes. The mold is then heated to the holding temperature at a heating rate of 5°C to 15°C / min and a heating power of 15% to 30%. The temperature is held for 2 to 12 minutes. After the holding period, the mold is cooled with the furnace. Once the temperature drops below 40°C, the vacuum is broken, the furnace is opened, and the sample is removed from the mold. The sample is then polished and peeled to obtain a high-performance magnesium-lithium alloy material. The holding temperature is 430°C to 480°C. In this invention, excessively low heating rates lead to coarse grains and reduced material preparation efficiency, while excessively high heating rates result in a significant difference between the programmed temperature and the actual furnace temperature, affecting the sintering quality. Therefore, to balance sintering efficiency and quality, a heating rate of 15℃ / min to 35℃ / min is chosen to heat the material to 15℃ to 50℃ below the holding temperature, followed by a holding period of 1 to 2 minutes. This ensures synchronization between the programmed and actual temperatures, guaranteeing sintering quality. Then, to avoid large fluctuations in furnace temperature during the holding period due to excessively rapid heating rates, which could affect the sintering quality, a lower heating rate is chosen to heat the material to the holding temperature. Again, to balance sintering efficiency and quality, a heating rate of 5℃ / min to 15℃ / min is chosen to heat the material to the holding temperature and hold it. After holding, the material is cooled with the furnace until it drops below 40℃. The vacuum is then broken, the furnace is opened, and the sample is removed from the mold. The resulting sample is then polished and peeled. To obtain high-performance magnesium-lithium alloy materials, sintering temperature is crucial for sintering quality. Lower sintering temperatures fail to allow for the formation of strong sintering necks between powder particles, thus hindering densification and resulting in poor material performance. Conversely, excessively high sintering temperatures can lead to overheating, the generation of large amounts of low-melting-point liquid phases, and the volatilization of Mg and Li elements, all of which negatively impact alloy performance. To balance sintering efficiency and quality, a holding temperature of 430℃–480℃ is selected. The holding time at this temperature is 2–12 minutes. Shorter holding times result in insufficient element diffusion between powder particles, preventing the formation of strong sintering necks and leading to lower matrix density. Conversely, excessively long holding times increase sintering time and costs, and can also cause grain growth, resulting in coarse structures and affecting material performance. Therefore, selecting an appropriate holding time is also important to balance sintering efficiency and quality.

[0020] The above method is characterized in that the compressive strength of the high-performance magnesium-lithium alloy material in step three is greater than 500 MPa.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] 1. In this invention, magnesium-lithium alloy powder is used as raw material, and magnesium-lithium alloy material is prepared by spark plasma sintering. The resulting material has uniform composition and fine structure, and the structure and microstructure of the material can be designed and easily controlled, with a compressive strength greater than 500 MPa.

[0023] 2. Compared with the melting and casting method, the present invention omits the stirring, blowing, and impurity removal processes in the melting process, as well as the cutting and homogenization processes after melting and casting. Therefore, the process flow of this method is short, the preparation efficiency is high, and the material utilization rate is high. The magnesium-lithium alloy material prepared by the present invention can achieve near-net-shape forming, and the material structure has advantages such as fine grains and uniform composition, which are unmatched by the melting and casting method.

[0024] 3. This invention uses spark plasma sintering to prepare magnesium-lithium alloy materials. The preparation method is simple, flexible, and universal. The shape and size of the material are easy to control, and materials of different shapes and sizes can be obtained. At the same time, the composition and microstructure of the material can be designed and easily controlled, and can be adjusted according to application requirements.

[0025] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of loading Mg-8Li-9Al-1Zn alloy powder into a mold in step one of the present invention.

[0027] Figure 2 This is a schematic diagram of the mold containing compacted powder obtained in step two of this invention.

[0028] Figure 3 This is a schematic diagram of the vacuum sintering and densification of the mold containing compacted powder in step three of the present invention.

[0029] Figure 4 This is a morphology diagram of the Mg-8Li-9Al-1Zn alloy powder used in Example 1 of the present invention.

[0030] Figure 5 This is a particle size distribution diagram of the Mg-8Li-9Al-1Zn alloy powder used in Example 1 of the present invention.

[0031] Figure 6 This is a physical image of the high-performance Mg-8Li-9Al-1Zn alloy material obtained in Example 1 of the present invention.

[0032] Figure 7This is a microstructure diagram of the high-performance Mg-8Li-9Al-1Zn alloy material obtained in Example 1 of the present invention.

[0033] Figure 8 The mechanical properties diagram of the high-performance Mg-8Li-9Al-1Zn alloy material obtained in Example 1 of this invention is shown. Detailed Implementation

[0034] Figure 1 This is a schematic diagram illustrating the loading of Mg-8Li-9Al-1Zn alloy powder into a mold in step one of this invention. Figure 2 This is a schematic diagram of the mold containing compacted powder obtained in step two of this invention. Figure 3 This is a schematic diagram illustrating the vacuum sintering and densification of the mold containing compacted powder in step three of this invention. Figures 1-3 As can be seen from the diagram, the present invention first loads Mg-8Li-9Al-1Zn alloy powder into a mold, then vibrates the mold to spread the powder evenly inside the mold, then compacts the powder through the upper and lower pressure heads of the mold, and finally vacuum sintersulates the mold containing the compacted powder to densify it. Figure 3 The medium F and the thick arrow indicate the pressure applied to the powder during vacuum sintering densification. Figure 3 The curve with the arrow in the middle represents the pulse current, which is used to obtain high-performance magnesium-lithium alloy materials in the mold.

[0035] Example 1

[0036] This embodiment includes the following steps:

[0037] Step 1: Weigh 10g of Mg-8Li-9Al-1Zn alloy powder with a particle size of -100 mesh to -325 mesh, then put it into a graphite mold, and then vibrate the mold to spread the powder evenly inside the mold, thus obtaining a mold containing a layer of Mg-8Li-9Al-1Zn alloy powder.

[0038] Step 2: Compact the powder in the powder-filling mold obtained in Step 1 using the upper and lower pressure heads of the mold to obtain a mold containing compacted powder.

[0039] Step 3: Place the mold containing the compacted powder obtained in Step 2 into a spark plasma sintering furnace, apply pressure of 30 MPa, and evacuate until the vacuum degree reaches 1×10⁻⁶. -4 Pa ~ 1×10 -5 After Pa, the sample was heated to 390°C at a heating rate of 30°C / min and a heating power of 18%, and then held for 1 min. Then, it was heated to 440°C at a heating rate of 10°C / min and a heating power of 20%, and held for 5 min. After the holding period, the sample was cooled with the furnace. When the temperature dropped below 40°C, the vacuum was broken, the furnace was opened, and the sample was taken out of the mold. The sample was then polished and peeled to obtain a high-performance magnesium-lithium alloy material.

[0040] Testing revealed that the high-performance Mg-8Li-9Al-1Zn alloy material prepared in this embodiment has a diameter of 40 mm and a thickness of 5 mm. It has a dense structure, fine grains, and uniform composition. Compression performance testing showed that the material has a compressive strength of 524.63 MPa.

[0041] Figure 4 This is a morphology image of the Mg-8Li-9Al-1Zn alloy powder used in this embodiment. Figure 5 This is a particle size distribution diagram of the Mg-8Li-9Al-1Zn alloy powder used in this embodiment. Figure 4 and Figure 5 As can be seen from the data, the Mg-8Li-9Al-1Zn alloy powder used in this embodiment has a uniform particle size.

[0042] Figure 6 Here is a physical image of the high-performance Mg-8Li-9Al-1Zn alloy material obtained in this embodiment. Figure 6 As can be seen from the data, the high-performance Mg-8Li-9Al-1Zn alloy material obtained in this embodiment has a clear outline, no low-melting-point liquid phase appears at the edge of the sample, and the sample surface is flat and smooth, indicating that the sintering process is reasonably selected and the sample quality is good.

[0043] Figure 7 This is a microstructure diagram of the high-performance Mg-8Li-9Al-1Zn alloy material obtained in Example 1 of this invention. Figure 7 As can be seen from the data, the high-performance Mg-8Li-9Al-1Zn alloy material obtained in this embodiment has a relatively dense microstructure without defects such as pores, indicating that the Mg-8Li-9Al-1Zn alloy has achieved densification under this sintering process. At the same time, the grains are small and the microstructure is uniform, with no segregation phenomenon, which further confirms the rationality of the sintering process.

[0044] Figure 8 The mechanical property diagram of the high-performance Mg-8Li-9Al-1Zn alloy material obtained in Example 1 of this invention is shown below. Figure 8 As can be seen from the data, the high-performance Mg-8Li-9Al-1Zn alloy material obtained in this embodiment has a compressive strength of 524.63 MPa and a high compressive plasticity of close to 15%. This confirms that high strength can be obtained by preparing Mg-8Li-9Al-1Zn alloy through spark plasma sintering.

[0045] Comparative Example 1

[0046] Step 1: Weigh 10g of Mg-8Li-9Al-1Zn alloy powder with a particle size of -100 mesh to -325 mesh, then put it into a graphite mold, and then vibrate the mold to spread the powder evenly inside the mold, thus obtaining a mold containing a layer of Mg-8Li-9Al-1Zn alloy powder.

[0047] Step 2: Compact the powder in the powder-filling mold obtained in Step 1 using the upper and lower pressure heads of the mold to obtain a mold containing compacted powder.

[0048] Step 3: Place the mold containing the compacted powder obtained in Step 2 into a spark plasma sintering furnace, apply pressure of 10 MPa, and evacuate until the vacuum degree reaches 1×10⁻⁶. -4 Pa ~ 1×10 -5 After Pa, the temperature was increased to 390℃ at a heating rate of 30℃ / min and a heating power of 18%, and then held for 1 min. Then, the temperature was increased to 440℃ at a heating rate of 10℃ / min and a heating power of 20%, and held for 5 min. After the holding period, the temperature was cooled with the furnace. When the temperature dropped below 40℃, the vacuum was broken, the furnace was opened, and the sample was taken out of the mold. The obtained sample was polished and peeled to obtain the magnesium-lithium alloy material.

[0049] Testing revealed that the magnesium-lithium alloy material prepared in this comparative example had a large number of pores, indicating that it was not fully densified. Tests on its compressive properties showed that the material had a compressive strength of only 213.02 MPa, indicating poor performance.

[0050] A comparison between Example 1 and Comparative Example 1 shows that the material properties obtained by Comparative Example 1 using a lower pressure (10 MPa) during spark plasma sintering are poorer.

[0051] Example 2

[0052] This embodiment includes the following steps:

[0053] Step 1: Weigh 31g of Mg-8Li-9Al-1Zn alloy powder with a particle size of -100 mesh to -325 mesh, then put it into a graphite mold, and then vibrate the mold to make the powder spread evenly inside the mold, thus obtaining a mold containing a layer of Mg-8Li-9Al-1Zn alloy powder.

[0054] Step 2: Compact the powder in the powder-filling mold obtained in Step 1 using the upper and lower pressure heads of the mold to obtain a mold containing compacted powder.

[0055] Step 3: Place the mold containing the compacted powder obtained in Step 2 into a spark plasma sintering furnace, apply pressure of 60 MPa, and evacuate until the vacuum degree reaches 1×10⁻⁶. -4 Pa ~ 1×10 -5After Pa, the sample was heated to 390℃ at a heating rate of 30℃ / min and a heating power of 18%, and then held for 1 min. Then, it was heated to 420℃ at a heating rate of 10℃ / min and a heating power of 20%, and held for 3 min. After the holding period, the sample was cooled with the furnace. When the temperature dropped below 40℃, the vacuum was broken, the furnace was opened, and the sample was taken out of the mold. The sample was then polished and peeled to obtain a high-performance magnesium-lithium alloy material.

[0056] Testing revealed that the high-performance Mg-8Li-9Al-1Zn alloy material prepared in this embodiment has a diameter of 50 mm and a thickness of 10 mm. It has a dense structure, fine grains, and uniform composition. Compression performance testing showed that the material has a compressive strength of 501.42 MPa.

[0057] Comparative Example 2

[0058] Step 1: Weigh 31g of Mg-8Li-9Al-1Zn alloy powder with a particle size of -100 mesh to -325 mesh, then put it into a graphite mold, and then vibrate the mold to make the powder spread evenly inside the mold, thus obtaining a mold containing a layer of Mg-8Li-9Al-1Zn alloy powder.

[0059] Step 2: Compact the powder in the powder-filling mold obtained in Step 1 using the upper and lower pressure heads of the mold to obtain a mold containing compacted powder.

[0060] Step 3: Place the mold containing the compacted powder obtained in Step 2 into a spark plasma sintering furnace, apply pressure of 20 MPa, and evacuate until the vacuum degree reaches 1 × 10⁻⁶. -4 Pa ~ 1×10 -5 After Pa, the temperature was increased to 390℃ at a heating rate of 30℃ / min and a heating power of 18%, and then held for 3 minutes. After the holding period, the temperature was cooled with the furnace. When the temperature dropped below 40℃, the vacuum was broken, the furnace was opened, and the sample was taken out of the mold. The obtained sample was polished and peeled to obtain the magnesium-lithium alloy material.

[0061] Testing revealed that the magnesium-lithium alloy material prepared in this comparative example had a large number of pores, indicating that it was not fully densified. Tests on its compressive properties showed that the material had a compressive strength of only 193.42 MPa, which is poor performance.

[0062] A comparison between Example 2 and Comparative Example 2 shows that the material properties obtained by Comparative Example 2 using a lower sintering temperature (390°C) during spark plasma sintering are inferior.

[0063] Example 3

[0064] A layered density gradient magnesium-lithium composite material with a thickness of 8 mm and a diameter of 30 mm was prepared.

[0065] Step 1: Weigh 10g of Mg-8Li-9Al-1Zn alloy powder with a particle size of -100 mesh to -325 mesh, then put it into a graphite mold, and then vibrate the mold to spread the powder evenly inside the mold, thus obtaining a mold containing a layer of Mg-8Li-9Al-1Zn alloy powder.

[0066] Step 2: Compact the powder in the powder-filling mold obtained in Step 1 using the upper and lower pressure heads of the mold to obtain a mold containing compacted powder.

[0067] Step 3: Place the mold containing the compacted powder obtained in Step 2 into a spark plasma sintering furnace, apply pressure of 10 MPa, and evacuate until the vacuum degree reaches 1×10⁻⁶. -4 Pa ~ 1×10 -5 After Pa, the sample was heated to 415℃ at a heating rate of 15℃ / min and a heating power of 15%, and then held for 2 minutes. Then, it was heated to 430℃ at a heating rate of 5℃ / min and a heating power of 15%, and held for 2 minutes. After the holding period, the sample was cooled with the furnace. When the temperature dropped below 40℃, the vacuum was broken, the furnace was opened, and the sample was taken out of the mold. The sample was then polished and peeled to obtain a high-performance magnesium-lithium alloy material.

[0068] Testing revealed that the high-performance Mg-8Li-9Al-1Zn alloy material prepared in this embodiment has a diameter of 30 mm and a thickness of 8 mm. It has a dense structure, fine grains, and uniform composition. Compression performance testing showed that the material has a compressive strength of 517.25 MPa.

[0069] Example 4

[0070] This embodiment includes the following steps:

[0071] Step 1: Weigh 10g of Mg-8Li-9Al-1Zn alloy powder with a particle size of -100 mesh to -325 mesh, then put it into a graphite mold, and then vibrate the mold to spread the powder evenly inside the mold, thus obtaining a mold containing a layer of Mg-8Li-9Al-1Zn alloy powder.

[0072] Step 2: Compact the powder in the powder-filling mold obtained in Step 1 using the upper and lower pressure heads of the mold to obtain a mold containing compacted powder.

[0073] Step 3: Place the mold containing the compacted powder obtained in Step 2 into a spark plasma sintering furnace, apply pressure of 40 MPa, and evacuate until the vacuum degree reaches 1×10⁻⁶. -4 Pa ~ 1×10 -5After Pa, the sample was heated to 450℃ at a heating rate of 35℃ / min and 30% of the heating power, and then held for 1.5 min. Then, it was heated to 480℃ at a heating rate of 15℃ / min and 30% of the heating power, and held for 12 min. After the holding period, the sample was cooled with the furnace. When the temperature dropped below 40℃, the vacuum was broken, the furnace was opened, and the sample was taken out of the mold. The sample was then polished and peeled to obtain the high-performance magnesium-lithium alloy material.

[0074] Testing revealed that the high-performance Mg-8Li-9Al-1Zn alloy material prepared in this embodiment has a diameter of 40 mm and a thickness of 5 mm. It has a dense structure, fine grains, and uniform composition. Compression performance testing showed that the material has a compressive strength of 524.63 MPa.

[0075] Example 5

[0076] The difference between this embodiment and embodiment 4 is that a steel mold is used and the pressure of spark plasma sintering is 40 MPa.

[0077] Testing revealed that the high-performance Mg-8Li-9Al-1Zn alloy material prepared in this embodiment has a diameter of 40 mm and a thickness of 5 mm. It has a dense structure, fine grains, and uniform composition. Compression performance testing showed that the material has a compressive strength of 526.17 MPa.

[0078] Example 6

[0079] The difference between this embodiment and embodiment 4 is that a steel mold is used and the pressure of spark plasma sintering is 80 MPa.

[0080] Testing revealed that the high-performance Mg-8Li-9Al-1Zn alloy material prepared in this embodiment has a diameter of 40 mm and a thickness of 5 mm. It has a dense structure, fine grains, and uniform composition. Compressive strength testing showed that the material has a compressive strength of 547.09 MPa.

[0081] Example 7

[0082] The difference between this embodiment and embodiment 4 is that a steel mold is used and the pressure of spark plasma sintering is 100 MPa.

[0083] Testing revealed that the high-performance Mg-8Li-9Al-1Zn alloy material prepared in this embodiment has a diameter of 40 mm and a thickness of 5 mm. It has a dense structure, fine grains, and uniform composition. Compression performance testing showed that the material has a compressive strength of 559.10 MPa.

[0084] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A high-performance magnesium-lithium alloy material, characterized in that, This high-performance magnesium-lithium alloy material is obtained by compacting magnesium-lithium alloy powder into a mold and then sintering and densifying it; the magnesium-lithium alloy powder is prepared by gas atomization, the particle size of the magnesium-lithium alloy powder is -100 mesh, the morphology is spherical or near-spherical, and the composition of the magnesium-lithium alloy powder is: Mg-8Li-9Al-1Zn. The method for preparing the high-performance magnesium-lithium alloy material includes the following steps: Step 1: Weigh out Mg-8Li-9Al-1Zn alloy powder, then put it into the mold, and then vibrate the mold to spread the powder evenly inside the mold to obtain the powder filling mold. Step 2: Compact the powder in the powder-filling mold obtained in Step 1 using the upper and lower pressure heads of the mold to obtain a mold containing compacted powder. Step 3: The mold containing compacted powder obtained in Step 2 is subjected to vacuum sintering for densification, resulting in a high-performance magnesium-lithium alloy material. The vacuum sintering densification is performed by spark plasma sintering. The spark plasma sintering process is as follows: the mold containing compacted powder is placed in a spark plasma sintering furnace and pressurized and evacuated. The temperature is increased at a heating rate of 15℃ / min to 35℃ / min and a heating power of 15% to 30% to a temperature 15℃ to 50℃ below the holding temperature. The temperature is then held for 1 to 2 minutes. The temperature is then increased at a heating rate of 5℃ / min to 15℃ / min and a heating power of 15% to 30% to a holding temperature and held for 2 to 12 minutes. After the holding period, the furnace is cooled. Once the temperature drops below 40℃, the vacuum is broken, the furnace is opened, and the sample is removed from the mold. The resulting sample is then polished to remove the outer layer, yielding the high-performance magnesium-lithium alloy material. The holding temperature is 430℃ to 480℃.

2. The high-performance magnesium-lithium alloy material according to claim 1, characterized in that, The mold mentioned in step one is a graphite mold or a steel mold.

3. The high-performance magnesium-lithium alloy material according to claim 2, characterized in that, If a graphite mold is used, the pressure of vacuum sintering densification is 10MPa~40MPa; if a steel mold is used, the pressure of vacuum sintering densification is 40MPa~100MPa.

4. The high-performance magnesium-lithium alloy material according to claim 1, characterized in that, The high-performance magnesium-lithium alloy material described in step three has a compressive strength greater than 500 MPa.

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