A near-equi-molar solute multi-alloyed high strength and toughness magnesium alloy and a preparation method thereof

Abstract

The application discloses a near-equal-molar solute multi-alloyed high-strength and high-toughness magnesium alloy and a preparation method thereof, and belongs to the field of metal materials. 100‑x (ABCDE) x , x is an atomic percentage content, x=0.15at.%-1.15at.%, wherein A and B are two of Ce, La, Nd, Sm, Gd, Y and Er elements, C and D are two of Zn, Sn, Ca and Sr, E is one of Mn, Zr and Sc, and the balance is magnesium and inevitable impurities. La, Ce, Sm, Nd, Zn, Mn and Ca and other elements are prone to occur in grain boundary. By increasing the amount of solute elements, the second phase formed after alloying is beneficial to form a heterogeneous structure having a synergistic optimization effect on strength and plasticity after conventional plastic deformation. The magnesium alloy prepared by the method has a tensile strength of 300-405 MPa, a yield strength of 290-395 MPa and an elongation of 4.8%-24.7%. Compared with other rare earth magnesium alloys having similar performance, the preparation cost is lower, and the alloy and the preparation method are worthy of industrial promotion.

Description

Technical Field

[0001] This invention belongs to the field of metallic materials, specifically relating to a near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy and its preparation method. Background Technology

[0002] High-entropy alloys have inspired academic research into other alloy systems due to their superior performance. However, not all alloy systems are suitable for the near-equimolar ratio principle of multi-component solute elements in high-entropy alloys. Taking magnesium alloys as an example of lightweight alloys, although many studies have shown that applying the near-equimolar ratio principle of multi-component solute elements in high-entropy alloys can significantly improve hardness and wear resistance, these magnesium-based high-entropy alloys often do not excel in strength performance. For instance, Chinese patent CN109082582A discloses a high-strength, high-toughness magnesium-based high-entropy alloy and its preparation method. The magnesium-based high-entropy alloy is composed of five elements: Mg, Al, Gd, Y, and Zn, with the following atomic percentages (at.%): Mg: 30–35%, Al: 20–25%, Gd: 15–20%, Y: 10–15%, and Zn: 10–15%. The magnesium-based high-entropy alloy has a microhardness of HV103.3–HV123.7, a room temperature compressive strength of 458–496 MPa, and a post-fracture compression ratio of 14.8–17.3%. This invention uses high amounts of rare earth elements Gd and Y in its preparation process, resulting in high production costs. The high degree of alloying makes deformation difficult, and the alloy preparation requires a vacuum melting furnace, hindering large-scale industrial production and promotion. Chinese Patent CN115261701A discloses a magnesium-based high-entropy alloy and its preparation method. This magnesium-based high-entropy alloy is composed of five elements: Mg, Al, Li, Zn, and Ti, with the following atomic percentages: Mg: 48–56%, Al: 20–22%, Li: 8–11%, Ti: 2–5%, and Zn: 11–15%. The preparation method includes an extrusion step: heating the alloy ingot to 300–350°C and extruding it using an extrusion die with an extrusion ratio of 10–60 to obtain the magnesium-based high-entropy alloy. The highest compressive strength of the extruded alloy in this patent is only 446 MPa, and this performance is obtained through high extrusion ratio deformation, so the performance is not outstanding. Argon gas is required during the vacuum induction furnace melting process, and the high Li content in this patent increases the production cost. The high content of solute elements weakens the lightweight advantage of magnesium alloys, and the limited slip system of magnesium alloys restricts their deformation capacity at high solute contents, limiting large-scale industrial production. Therefore, the amount of multi-element solute elements added should be reduced, while retaining the principle of near-equimolar ratios. This allows for targeted adjustments to the amount of a specific solute element based on performance test results to adapt to the performance requirements of diverse service environments. Compared to traditional alloy design methods (gradually adding auxiliary elements to optimize performance after determining the main element), this alloy design concept is expected to reduce trial-and-error costs, decrease the need for large-scale experiments, and quickly obtain the ideal alloy composition.

[0003] Furthermore, the selection and addition ratio of solute elements are crucial to the alloy's properties.

[0004] Selected solute elements (Ce, Nd, Sm, Er, La, Mn, Sr, and Ca, etc.) that readily induce grain boundary co-segregation, and whose addition forms precipitates that, when coupled with plastic deformation, introduce heterostructures into the microstructure, synergistically optimizing both strength and plasticity, will significantly improve the overall performance of the alloy. By adjusting the proportion of added solute elements, the degree of grain boundary co-segregation and the proportion of heterostructures in the microstructure can be optimized, thereby controlling the alloy's properties. This adjustment ensures that the alloy achieves optimal performance under different application environments, comprehensively improving its overall performance. This strategy not only provides a new optimization approach for alloy design but also makes it possible to customize alloy properties. Summary of the Invention

[0005] The purpose of this invention is to provide a near-equimolar solute-based multi-element alloy of high strength and toughness and its preparation method. The preparation process of this near-equimolar solute-based multi-element alloy of high strength and toughness is simple. Compared with alloys with comparable performance, this alloy exhibits lower preparation cost and is more economical.

[0006] This invention discloses a near-equimolar solute-based multi-element alloy with high strength and toughness, the chemical composition of which is Mg. 100-x (ABCDE) x x represents the atomic percentage content, x = 0.15 at.% to 1.15 at.%. Among them, A, B, C, D and E are solute elements. Solute elements A and B are any two of Ce, La, Nd, Sm, Gd, Y and Er. Solute elements C and D are any two of Zn, Sn, Ca and Sr. Solute element E is any one of Mn, Zr and Sc. The balance is magnesium and unavoidable impurities.

[0007] In one or more embodiments of the present invention, a preferred near-equimolar solute-based multi-element alloying high-strength and high-toughness magnesium alloy is provided, wherein the solute element composition is Gd, Y, Zn, Sn, Mn, and the preferred alloy composition based on this solute element composition is Mg. 99.75 -(GdYZnSnMn) 0.25 Mg 99.5 -(GdYZnSnMn) 0.5 and Mg 99.0 -(GdYZnSnMn) 1.0 The magnesium alloy has a tensile strength of 348–363 MPa, a yield strength of 337–356 MPa, and an elongation of 5.2–9.3%.

[0008] In one or more embodiments of the present invention, a preferred near-equimolar solute-based multi-element alloying high-strength and high-toughness magnesium alloy is provided, wherein the solute element composition is Gd, Y, Zn, Sn, Zr, and the preferred alloy composition based on this solute element composition is Mg.99.75 -(GdYZnSnZr) 0.25 Mg 99.5 -(GdYZnSnZr) 0.5 and Mg 99.25 -(GdYZnSnZr) 0.75 The magnesium alloy has a tensile strength of 390–405 MPa, a yield strength of 380–395 MPa, and an elongation of 4.8–10.5%.

[0009] In one or more embodiments of the present invention, a near equimolar solute-based multi-element alloy with high strength and toughness is preferred, wherein the solute element composition is Ce, Y, Zn, Ca, Zr, and the preferred alloy composition based on this solute element composition is Mg. 99.75 -(CeYZnCaZr) 0.25 Mg 99.5 -(CeYZnCaZr) 0.5 and Mg 99.25 -(CeYZnCaZr) 0.75 The magnesium alloy has a tensile strength of 358–370 MPa, a yield strength of 351–360 MPa, and an elongation of 7.8–10.3%.

[0010] In one or more embodiments of the present invention, a preferred near-equimolar solute-based multi-element alloying high-strength and high-toughness magnesium alloy is provided, wherein the solute element composition is Nd, Y, Zn, Ca, Zr, and the preferred alloy composition based on this solute element composition is Mg. 99.75 -(NdYZnCaZr) 0.25 Mg 99.5 -(NdYZnCaZr) 0.5 and Mg 99.25 -(NdYZnCaZr) 0.75 The magnesium alloy has a tensile strength of 360–384 MPa, a yield strength of 345–364 MPa, and an elongation of 15.8–17.7%.

[0011] In one or more embodiments of the present invention, a preferred near-equimolar solute-based multi-element alloying high-strength and high-toughness magnesium alloy has a solute element composition of SmYZnCaZr, and the preferred alloy composition based on this solute element composition is Mg. 99.8 -(SmYZnCaZr) 0.2 Mg 99.6 -(SmYZnCaZr) 0.4 and Mg 99.4 -(SmYZnCaZr) 0.6 The magnesium alloy has a tensile strength of 315–340 MPa, a yield strength of 290–318 MPa, and an elongation of 11.9–24.7%.

[0012] In one or more embodiments of the present invention, a near equimolar solute-based multi-element alloy with high strength and toughness is preferred, wherein the solute element composition is LaErZnSrSc, and the preferred alloy composition based on this solute element composition is Mg. 99.85 -(LaErZnSrSc) 0.15 Mg 99.7 -(LaErZnSrSc) 0.3 and Mg 99.4 -(LaErZnSrSc) 0.6 The magnesium alloy has a tensile strength of 343–355 MPa, a yield strength of 323–340 MPa, and an elongation of 17.9–22.8%.

[0013] In one or more embodiments of the present invention, a preferred near-equimolar solute-based multi-element alloying high-strength and high-toughness magnesium alloy has a solute element composition of Ce, Y, Zn, Ca, and Mn, and the preferred alloy composition based on this solute element composition is Mg. 99.7 -(CeYZnCaMn) 0.3 Mg 99.4 -(CeYZnCaMn) 0.6 and Mg 99.15 -(CeYZnCaMn) 0.85 and Mg 98.85 -(CeYZnCaMn) 1.15 The magnesium alloy has a tensile strength of 300–398 MPa, a yield strength of 290–394 MPa, and an elongation of 4.8–15.5%.

[0014] In this invention, rare earth elements with high affinity for elements A and B are added to magnesium alloys. These elements can combine with impurity elements, effectively purifying the melt quality and improving its purity. Simultaneously, rare earth elements react with elements C and D to form second-phase particles with high-temperature stability, maintaining stability at high temperatures and thus strengthening the alloy. Rare earth elements can also co-segregate with non-rare earth elements such as Zn and Ca at grain boundaries, forming element-enriched regions at these boundaries. This co-segregation not only enhances the grain boundary bonding force but also hinders dislocation movement through grain boundary pinning, resulting in a greater strengthening effect. Elements E can refine the grains in magnesium alloys. Through solid solution strengthening and heterogeneous nucleation mechanisms, these elements promote grain refinement, thereby improving the alloy's yield strength and tensile strength. By using near-equimolar solute element alloying, the amount of solute element added can not only control the degree of the aforementioned strengthening effect but also adjust the microstructure to control the alloy's properties.

[0015] In this invention, the solute element content is set to x = 0.15 at.% to 1.15 at.%. As the alloy element content increases, the material cost also increases accordingly. High-content alloying may require more complex production processes, further increasing costs. Excessive alloying can easily introduce more intermetallic compounds. These intermetallic compounds may form brittle phases at grain boundaries, reducing the material's plasticity and toughness, and affecting its overall performance. Excessive addition of alloying elements may disrupt the balance between the material's strength and plasticity. While it may improve the material's strength to some extent, excessive alloying can impair plasticity, reducing the material's ductility and toughness.

[0016] The preferred method for preparing a near-equimolar solute-based multi-element alloyed high-strength and high-toughness magnesium alloy of the present invention includes:

[0017] Raw material preparation: Based on the corresponding solute element groups, select Mg ingots, Zn ingots, Sn ingots, Mg-30Zr master alloy, Mg-25Y master alloy, Mg-25Gd master alloy, Mg-30Sm master alloy, Mg-20La master alloy, Mg-40Ce master alloy, Mg-23Nd master alloy, Mg-15Er master alloy, Mg-25Ca master alloy, Mg-10Sc master alloy, Mg-38Sr master alloy and anhydrous manganese chloride particles as raw materials in proportion;

[0018] Melting and casting: The raw materials are added to an electric resistance furnace and melted and mixed at a temperature of 680℃-750℃; the molten magnesium alloy melt is cast into magnesium alloy ingots using an electromagnetic semi-continuous casting method at a temperature of 720℃-750℃.

[0019] Extrusion pretreatment: Solution treatment of magnesium alloy ingots;

[0020] Thermal extrusion: After solution treatment, magnesium alloy ingots are held at the extrusion temperature for 1 hour and then extruded to obtain magnesium alloy rods.

[0021] The near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy and its preparation method thereof, wherein during the smelting process, the surface of the raw material is covered with flux; and / or, the flux is selected from one or more of magnesium alloy flux No. 2, magnesium alloy flux No. 5 and magnesium alloy flux No. 6 (RJ-2, RJ-5 and RJ-6);

[0022] The near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy and its preparation method, wherein the electromagnetic semi-continuous casting method has a current between 100A and 130A and a frequency between 15Hz and 30Hz.

[0023] The near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy and its preparation method, wherein the solution treatment is: holding the magnesium alloy ingot at 450℃-520℃ for 12h-16h and then water quenching.

[0024] The near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy and its preparation method thereof, wherein the extrusion temperature of the magnesium alloy rod is between 270℃ and 350℃; and / or, the extrusion ratio of the magnesium alloy rod is between 17 and 25; and / or, the extrusion speed of the magnesium alloy rod is between 0.2 mm / s and 2 mm / s.

[0025] The beneficial effects of this invention are as follows:

[0026] (1) The alloying elements selected in this invention include low-solid-solubility elements such as Ca, Sr, La, Ce, Sm, and Nd, which can form high-temperature resistant second phases. These second phases play the role of grain boundary pinning and heterogeneous nucleation sites during alloy deformation, effectively promoting dynamic recrystallization, refining grains, and thus significantly improving the yield strength and work hardening ability of the alloy, while weakening the texture and enhancing the formability of the alloy. In addition, the selected solute elements such as Ce, Nd, Sm, Er, La, Mn, Sr, and Ca have the characteristic of easily forming grain boundary co-segregation. The second phase formed after alloying is beneficial to forming a heterogeneous structure with synergistic optimization effect on strength and plasticity after plastic deformation. In particular, the segregation of Zr elements in the extruded alloy structure in this invention further improves the comprehensive performance of the alloy, achieving dual optimization of performance and formability.

[0027] (2) By adjusting the proportion of solute elements added, the degree of grain boundary co-segregation and the proportion of heterostructures in the microstructure can be optimized, thereby controlling the alloy's properties. Compared with existing technologies, the near-equimolar solute-based multi-element alloying method for preparing high-strength and high-toughness magnesium alloys according to embodiments of the present invention is simple and has better mechanical properties. This strategy not only provides a new optimization approach for alloy design but also makes it possible to customize alloy properties.

[0028] (3) The magnesium alloy prepared by the method of the present invention has a tensile strength of 300-405 MPa, a yield strength of 290-395 MPa, and an elongation of 4.8-24.7%. Compared with other rare earth magnesium alloys with similar properties, the preparation cost is lower, making it an alloy and preparation method worthy of industrial promotion. Attached Figure Description

[0029] Figure 1 Here are SEM images of the near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy of Example 1 of this invention; (a) Mg 99.75 -(GdYZnSnMn) 0.25 (b)Mg99.5 -(GdYZnSnMn) 0.5 (c)Mg 99.0 -(GdYZnSnMn) 1.0 .

[0030] Figure 2 This is the stress-strain curve of the near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy of Example 1 of the present invention.

[0031] Figure 3 Here is a metallographic diagram of the near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy of Example 1 of this invention; (a) Mg 99.75 -(GdYZnSnMn) 0.25 (b)Mg 99.5 -(GdYZnSnMn) 0.5 (c)Mg 99.0 -(GdYZnSnMn) 1.0 .

[0032] Figure 4 Here are SEM images of the near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy of Example 2 of this invention; (a) Mg 99.75 -(NdYZnCaZr) 0.25 (b)Mg 99.5 -(NdYZnCaZr) 0.5 (c)Mg 99.25 -(NdYZnCaZr) 0.75 .

[0033] Figure 5 This is the stress-strain curve of the near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy of Example 2 of the present invention.

[0034] Figure 6 These are metallographic images of the near-equimolar solute multi-element alloyed high-strength and high-toughness magnesium alloy of Example 2 of the present invention; (a)(b) Mg 99.75 -(NdYZnCaZr) 0.25 (c)(d)Mg 99.5 -(NdYZnCaZr) 0.5 ,(e)(f)Mg 99.25 -(NdYZnCaZr) 0.75 .

[0035] Figure 7 This is a schematic diagram of the preparation process of the present invention; (a) casting ingot, (b) solution treatment, (c) extrusion deformation, (d) extruded bar. Detailed Implementation

[0036] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0037] Unless otherwise expressly stated, throughout this specification, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0038] The present invention will be further described below with reference to specific embodiments.

[0039] The preparation process of this invention embodiment is as follows: Figure 7 As shown.

[0040] Example 1

[0041] (1) Ingredient Design

[0042] In this embodiment, the solute element combination is GdYZnSnMn, and the preferred alloy composition based on this solute element combination is Mg. 99.75 -(GdYZnSnMn) 0.25 Mg 99.5 -(GdYZnSnMn) 0.5 and Mg 99.0 -(GdYZnSnMn) 1.0 The designed alloy is abbreviated as VTWZM. Due to the inevitable element loss during the actual traditional gravity casting process, the actual composition is shown in Table 1.

[0043] Table 1 shows the actual composition of near-equimolar solute-based magnesium alloys with a solute element combination of Gd, Y, Zn, Sn, and Mn.

[0044]

[0045]

[0046] (2) Preparation method

[0047] In the experiment, Mg, Sn, and Zn were added using commercially available pure metal ingots, while Gd, Y, and Mn were added using Mg-25Gd master alloy, Mg-25Y master alloy, and anhydrous manganese chloride granules, respectively. During the melting process, a layer of No. 2 magnesium alloy flux (RJ-2) was evenly sprinkled on the bottom of the crucible. After the magnesium ingots were placed in, a layer of No. 2 magnesium alloy flux was also evenly sprinkled on the surface of the magnesium ingots. The resistance furnace temperature was set to 720℃. After all the magnesium ingots had melted, the melt temperature was raised to 730℃, and Mg-25Gd master alloy, Mg-25Y master alloy, Sn ingots, and Zn ingots were added. The mixture was held at this temperature for 20 minutes and then stirred for 5 minutes. After stirring, No. 5 magnesium alloy flux (RJ-5) was used to cover the surface of the melt. Throughout the stirring process, a mixture of CO2 and SF6 with a volume ratio of 99:1 was used for protection. After stirring, the temperature was controlled at 730℃. Anhydrous manganese chloride particles were pressed into the melt using a pressure shield. After removing the oxide slag from the melt surface, a small amount of No. 5 magnesium alloy flux was applied to the melt surface. The melt was allowed to stand for 15 minutes, and then the melt temperature was lowered to 690℃. After standing, the melt temperature was raised to 730℃, and the melt was refined for 5 minutes using No. 5 magnesium alloy flux in a CO2+SF6 mixed atmosphere with a volume ratio of 99:1. After standing at 720℃ for 15 minutes, the melt was cast using an electromagnetic semi-continuous casting system to obtain magnesium alloy ingots. During the casting process, a CO2+SF6 mixed gas with a volume ratio of 99:1 was used for protection. The current used in the electromagnetic semi-continuous casting method was 100A, and the electromagnetic frequency in the electromagnetic stirring was 25Hz.

[0048] The ingots were solution treated in a muffle furnace at 520°C for 12 hours, followed by cooling in water at room temperature. The surface oxide layer of the solution-treated magnesium alloy ingots was removed, and then extrusion deformation was performed at a temperature of 270°C, an extrusion ratio of 17, and an extrusion speed of 0.4 mm / s. The mechanical properties of the alloy obtained in Example 1 are summarized in Table 2.

[0049] Table 2 Mechanical properties of near-equimolar solute-based multi-element magnesium alloys with solute element combinations of Gd, Y, Zn, Sn, and Mn

[0050]

[0051] The SEM morphology of the near-equimolar solute-based multi-element alloyed high-strength and high-toughness magnesium alloy prepared in Example 1 is shown below. Figure 1 As shown, (a)Mg 99.75 -(GdYZnSnMn) 0.25 (b)Mg 99.5 -(GdYZnSnMn) 0.5 (c)Mg 99.0 -(GdYZnSnMn) 1.0 Stress-strain curves are as follows: Figure 2As shown; the as-cast metallographic structure is as follows Figure 3 As shown, (a)Mg 99.75 -(GdYZnSnMn) 0.25 (b)Mg 99.5 -(GdYZnSnMn) 0.5 (c)Mg 99.0 -(GdYZnSnMn) 1.0 .

[0052] Example 2

[0053] (1) Ingredient Design

[0054] In this embodiment, the solute element combination is Nd, Y, Zn, Ca, Zr, and the preferred alloy composition based on this solute element combination is Mg. 99.75 -(NdYZnCaZr) 0.25 Mg 99.5 -(NdYZnCaZr) 0.5 and Mg 99.25 -(NdYZnCaZr) 0.75 The designed alloy is abbreviated as NWKZX. Due to the inevitable element loss during the actual traditional gravity casting process, the actual composition is shown in Table 3.

[0055] Table 3 shows the actual composition of near-equimolar solute-based magnesium alloys with Nd, Y, Zn, Ca, and Zr as the solute element combination.

[0056]

[0057] (2) Preparation method

[0058] In the experiment, Mg and Zn were added using commercially pure metal ingots, while Nd, Y, Ca and Zr were added using Mg-23Nd master alloy, Mg-25Y master alloy, Mg-25Ca master alloy and Mg-30Zr master alloy, respectively.

[0059] During the smelting process, a layer of No. 2 magnesium alloy flux was evenly sprinkled on the bottom of the crucible. After the magnesium ingot was placed in, a layer of No. 2 magnesium alloy flux was also evenly sprinkled on the surface of the magnesium ingot. The resistance furnace temperature was set to 720℃. After the magnesium ingot was completely melted, the melt temperature was raised to 740℃, and Zn ingot, Mg-23Nd master alloy, and Mg-25Y master alloy were added. The mixture was held for 15 minutes. The addition of master alloys was carried out under the protection of a mixed gas of CO2 + SF6 with a volume ratio of 99:1. The melt temperature was raised to 750℃, and Mg-30Zr master alloy was added. The mixture was stirred until it was completely melted, and a small amount of No. 5 magnesium alloy flux was placed on the surface of the melt. After holding for 10 minutes, the melt temperature was lowered to 690℃, and Mg-25Ca master alloy was added to the melt. A pressure shield was used to press it into the melt to prevent it from floating and to ensure that it was completely melted. The melt was allowed to stand until the temperature returned to 730°C. Magnesium alloy flux No. 5 was used, and the melt was refined for 5 minutes in a CO2 + SF6 mixed atmosphere with a volume ratio of 99:1. After standing at 730°C for 15 minutes, the melt was cast using an electromagnetic semi-continuous casting system to obtain magnesium alloy ingots. Throughout the casting process, a CO2 + SF6 mixed gas with a volume ratio of 99:1 was used for protection. The electromagnetic semi-continuous casting method used a current of 110A, and the electromagnetic frequency during electromagnetic stirring was 20Hz.

[0060] The ingots were solution treated in a muffle furnace at 450°C for 12 hours, followed by cooling in water at room temperature. The surface oxide layer of the solution-treated magnesium alloy ingots was removed, and then extrusion deformation was performed at a temperature of 325°C, an extrusion ratio of 17, and an extrusion speed of 0.5 mm / s. The mechanical properties of the alloy obtained in Example 2 are summarized in Table 4.

[0061] Table 4 Mechanical properties of near-equimolar solute-based multi-element magnesium alloys with Nd, Y, Zn, Ca, and Zr solute element combinations

[0062]

[0063]

[0064] The SEM morphology of the near-equimolar solute-based multi-element alloyed high-strength and high-toughness magnesium alloy prepared in Example 2 is shown below. Figure 4 As shown, (a)Mg 99.75 -(NdYZnCaZr) 0.25 (b)Mg 99.5 -(NdYZnCaZr) 0.5 (c)Mg 99.25 -(NdYZnCaZr) 0.75 Stress-strain curves are as follows: Figure 5 As shown. The as-cast metallographic structure is as follows. Figure 6 As shown, (a)(b)Mg 99.75-(NdYZnCaZr) 0.25 (c)(d)Mg 99.5 -(NdYZnCaZr) 0.5 ,(e)(f)Mg 99.25 -(NdYZnCaZr) 0.75 .

[0065] Example 3

[0066] (1) Ingredient Design

[0067] In this embodiment, the solute element combination is SmYZnCaZr, and the preferred alloy composition based on this solute element combination is Mg. 99.8 -(SmYZnCaZr) 0.2 Mg 99.6 -(SmYZnCaZr) 0.4 and Mg 99.4 -(SmYZnCaZr) 0.6 The designed alloy is abbreviated as SWKZX. Due to the inevitable element loss during the actual traditional gravity casting process, the actual composition is shown in Table 5.

[0068] Table 5 shows the actual composition of near-equimolar solute-based multi-element magnesium alloys with solute element combinations of SmYZnCaZr.

[0069]

[0070] (2) Preparation method

[0071] In the experiment, Mg and Zn were added using commercially pure metal ingots, while Sm, Y, Ca and Zr were added using Mg-30Sm master alloy, Mg-25Y master alloy, Mg-25Ca master alloy and Mg-30Zr master alloy, respectively.

[0072] During the smelting process, a layer of No. 2 magnesium alloy flux was evenly sprinkled on the bottom of the crucible. After the magnesium ingot was placed in, a layer of No. 2 magnesium alloy flux was also evenly sprinkled on the surface of the magnesium ingot. The resistance furnace temperature was set to 720℃. After the magnesium ingot was completely melted, the melt temperature was raised to 730℃, and Zn ingot, Mg-30Sm master alloy, and Mg-25Y master alloy were added. The mixture was held for 15 minutes. The addition of the master alloys was carried out under the protection of a mixed gas of CO2 + SF6 with a volume ratio of 99:1. The melt temperature was raised to 750℃, and Mg-30Zr master alloy was added and stirred until it was completely melted. A small amount of No. 5 magnesium alloy flux was then placed on the surface of the melt. After holding for 10 minutes, the melt temperature was lowered to 680℃, and Mg-25Ca master alloy was added to the melt. A pressure shield was used to press it into the melt to prevent it from floating and to ensure that it was completely melted. The melt was allowed to stand until the temperature returned to 730°C. Then, using No. 5 magnesium alloy flux, it was refined for 5 minutes in a CO2 + SF6 mixed atmosphere with a volume ratio of 99:1. After standing at 740°C for 15 minutes, the melt was cast into magnesium alloy ingots using an electromagnetic semi-continuous casting system. Throughout the casting process, a CO2 + SF6 mixed gas with a volume ratio of 99:1 was used for protection. The electromagnetic semi-continuous casting method used a current of 120A, and the electromagnetic frequency during electromagnetic stirring was 30Hz.

[0073] The ingots were solution treated in a muffle furnace at 520°C for 16 hours, followed by cooling in water at room temperature. The surface oxide layer of the solution-treated magnesium alloy ingots was removed, and then extrusion deformation was performed at a temperature of 300°C, an extrusion ratio of 17, and an extrusion speed of 1 mm / s. The mechanical properties of the alloy obtained in Example 3 are summarized in Table 6.

[0074] Table 6 Mechanical properties of near-equimolar solute-based multi-element magnesium alloys with solute element combinations of SmYZnCaZr

[0075]

[0076] Example 4

[0077] (1) Ingredient Design

[0078] In this embodiment, the solute element combination is Ce, Y, Zn, Ca, Zr, and the preferred alloy composition based on this solute element combination is Mg. 99.75 -(CeYZnCaZr) 0.25 Mg 99.5 -(CeYZnCaZr) 0.5 and Mg 99.25 -(CeYZnCaZr) 0.75 The designed alloy is abbreviated as CWKZX. Due to the inevitable element loss during the actual traditional gravity casting process, the actual composition is shown in Table 7.

[0079] Table 7 shows the actual composition of near-equimolar solute-based magnesium alloys with Ce, Y, Zn, Ca, and Zr as the solute element combination.

[0080]

[0081] (2) Preparation method

[0082] In the experiment, Mg and Zn were added using commercially pure metal ingots, while Ce, Y, Ca and Zr were added using Mg-40Ce master alloy, Mg-25Y master alloy, Mg-25Ca master alloy and Mg-30Zr master alloy, respectively.

[0083] During the smelting process, a layer of No. 2 magnesium alloy flux was evenly sprinkled on the bottom of the crucible. After the magnesium ingot was placed in, a layer of No. 2 magnesium alloy flux was also evenly sprinkled on the surface of the magnesium ingot. The resistance furnace temperature was set to 720℃. After the magnesium ingot was completely melted, the melt temperature was raised to 720℃, and Mg-40Ce master alloy and Mg-25Y master alloy were added. The mixture was held for 15 minutes. The addition of master alloys was carried out under the protection of a mixed gas of CO2 + SF6 with a volume ratio of 99:1. The melt temperature was raised to 740℃, and Mg-30Zr master alloy was added. The mixture was stirred until it was completely melted, and a small amount of No. 5 magnesium alloy flux was placed on the surface of the melt. After holding for 10 minutes, the melt temperature was lowered to 680℃, and Mg-25Ca master alloy was added to the melt. A pressure shield was used to press it into the melt to prevent it from floating and to ensure that it was completely melted. The melt was allowed to stand until the temperature returned to 730°C. Magnesium alloy flux No. 6 was used, and the melt was refined for 5 minutes in a CO2 + SF6 mixed atmosphere with a volume ratio of 99:1. After standing at 740°C for 15 minutes, the melt was cast using an electromagnetic semi-continuous casting system to obtain magnesium alloy ingots. Throughout the casting process, a CO2 + SF6 mixed gas with a volume ratio of 99:1 was used for protection. The electromagnetic semi-continuous casting method used a current of 130A, and the electromagnetic stirring frequency was 15Hz.

[0084] The ingots were solution treated in a muffle furnace at 480°C for 12 hours, followed by cooling in water at room temperature. The surface oxide layer of the solution-treated magnesium alloy ingots was removed, and then extrusion deformation was performed at a temperature of 300°C, an extrusion ratio of 17, and an extrusion speed of 0.2 mm / s. The mechanical properties of the alloy obtained in Example 4 are summarized in Table 8.

[0085] Table 8 shows the actual composition of near-equimolar solute-based magnesium alloys with Ce, Y, Zn, Ca, and Zr as the solute element combination.

[0086]

[0087] Example 5

[0088] (1) Ingredient Design

[0089] In this embodiment, the solute element combination is GdYZnSnZr, and the preferred alloy composition based on this solute element combination is Mg. 99.75 -(GdYZnSnZr) 0.25 Mg 99.5 -(GdYZnSnZr) 0.5 and Mg 99.25 -(GdYZnSnZr) 0.75 The designed alloy is abbreviated as VWZTK, and its actual composition is shown in Table 9.

[0090] Table 9 shows the actual composition of near-equimolar solute-based multi-element magnesium alloys with solute element combinations of Gd, Y, Zn, Sn, and Zr.

[0091]

[0092] (2) Preparation method

[0093] In the experiment, Mg, Sn and Zn were added using commercially pure metal ingots, while Gd, Y and Zr were added using Mg-25Gd master alloy, Mg-25Y master alloy and Mg-30Zr master alloy, respectively.

[0094] During the smelting process, a layer of No. 2 magnesium alloy flux was evenly sprinkled on the bottom of the crucible. After the magnesium ingot was placed in the resistance furnace, a layer of No. 2 magnesium alloy flux was also evenly sprinkled on the surface of the magnesium ingot. The temperature of the resistance furnace was set to 720℃. After the magnesium ingot was completely melted, the melt temperature was raised to 720℃, and Sn ingot, Zn ingot, Mg-25Gd master alloy, and Mg-25Y master alloy were added. The mixture was held for 15 minutes. The addition of the master alloys was carried out under the protection of a mixed gas of CO2 and SF6 with a volume ratio of 99:1. The melt temperature was raised to 740℃, and Mg-30Zr master alloy was added and stirred until it was completely melted. A small amount of No. 6 magnesium alloy flux (RJ-6) was covered on the surface of the melt. The mixture was allowed to stand until the melt temperature rose back to 730℃, and then refined for 5 minutes using No. 5 magnesium alloy flux under a mixed atmosphere of CO2 and SF6 with a volume ratio of 99:1. After standing at 750℃ for 15 minutes, magnesium alloy ingots were obtained by melt casting using an electromagnetic semi-continuous casting system. During the casting process, a mixed gas of CO2 and SF6 with a volume ratio of 99:1 was used for protection. The current used in the electromagnetic semi-continuous casting method was 110A, and the electromagnetic frequency in the electromagnetic stirring was 30Hz.

[0095] The ingots were solution treated in a muffle furnace at 510°C for 12 hours, followed by cooling in water at room temperature. The surface oxide layer of the solution-treated magnesium alloy ingots was removed, and then extrusion deformation was performed at a temperature of 270°C, an extrusion ratio of 17, and an extrusion speed of 0.2 mm / s. The mechanical properties of the alloy obtained in Example 5 are summarized in Table 10.

[0096] Table 10 shows the actual composition of near-equimolar solute-based magnesium alloys with solute element combinations of Gd, Y, Zn, Sn, and Zr.

[0097]

[0098] Example 6

[0099] (1) Ingredient Design

[0100] In this embodiment, the solute element combination is LaErZnSrSc, and the preferred alloy composition based on this solute element combination is Mg. 99.85 -(LaErZnSrSc) 0.15 Mg 99.7 -(LaErZnSrSc) 0.3 and Mg 99.4 -(LaErZnSrSc) 0.6 The designed alloy is abbreviated as LRZJSc. Due to the inevitable element loss during the actual traditional gravity casting process, the actual composition is shown in Table 11.

[0101] Table 11 shows the actual composition of near-equimolar solute-based magnesium alloys with LaErZnSrSc as the solute element combination.

[0102]

[0103]

[0104] (2) Preparation method

[0105] In the experiment, Mg and Zn were added using commercially pure metal ingots, while La, Er, Sr and Sc were added using Mg-20La master alloy, Mg-15Er master alloy, Mg-10Sc master alloy and Mg-38Sr master alloy, respectively.

[0106] During the smelting process, a layer of No. 2 magnesium alloy flux was evenly sprinkled on the bottom of the crucible. After the magnesium ingot was placed in, a layer of No. 2 magnesium alloy flux was also evenly sprinkled on the surface of the magnesium ingot. The resistance furnace temperature was set to 720℃. After the magnesium ingot was completely melted, the melt temperature was raised to 720℃, and Zn ingot, Mg-20La master alloy, and Mg-15Er master alloy were added. The mixture was held for 15 minutes. The addition of the master alloys was carried out under the protection of a mixed gas of CO2 + SF6 with a volume ratio of 99:1. The melt temperature was raised to 740℃, and Mg-10Sc master alloy was added. The mixture was stirred until it was completely melted, and a small amount of No. 5 magnesium alloy flux was placed on the surface of the melt. After holding for 10 minutes, the melt temperature was lowered to 680℃, and Mg-38Sr master alloy was added to the melt. A pressure shield was used to press it into the melt to prevent it from floating and to ensure that it was completely melted. The melt was allowed to stand until the temperature returned to 730°C. Magnesium alloy flux No. 6 was used, and the melt was refined for 5 minutes in a CO2 + SF6 mixed atmosphere with a volume ratio of 99:1. After standing at 740°C for 15 minutes, the melt was cast into magnesium alloy ingots using an electromagnetic semi-continuous casting system. Throughout the casting process, a CO2 + SF6 mixed gas with a volume ratio of 99:1 was used for protection. The electromagnetic semi-continuous casting method used a current of 120A, and the electromagnetic frequency during electromagnetic stirring was 15Hz.

[0107] The ingots were solution treated in a muffle furnace at 510°C for 12 hours, followed by cooling in water at room temperature. The surface oxide layer of the solution-treated magnesium alloy ingots was removed, and then extrusion deformation was performed at a temperature of 350°C, an extrusion ratio of 25, and an extrusion speed of 2 mm / s. The mechanical properties of the alloy obtained in Example 6 are summarized in Table 12.

[0108] Table 12 shows the actual composition of near-equimolar solute-based magnesium alloys with LaErZnSrSc as the solute element combination.

[0109]

[0110] Example 7

[0111] (1) Ingredient Design

[0112] In this embodiment, the solute element combination is CeYZnCaMn, and the preferred alloy composition based on this solute element combination is Mg. 99.7 -(CeYZnCaMn) 0.3 Mg 99.4 -(CeYZnCaMn) 0.6 and Mg 99.15 -(CeYZnCaMn) 0.85 and Mg 98.85 -(CeYZnCaMn) 1.15The designed alloy is abbreviated as CWZXM. Due to the inevitable element loss during the actual traditional gravity casting process, the actual composition is shown in Table 13.

[0113] Table 13 shows the actual composition of near-equimolar solute-based magnesium alloys with Ce, Y, Zn, Ca, and Mn as the solute element combination.

[0114]

[0115] (2) Preparation method

[0116] In the experiment, Mg and Zn were added using commercially pure metal ingots, while Ce, Y, Ca and Mn were added using Mg-40Ce master alloy, Mg-25Y master alloy, Mg-25Ca master alloy and anhydrous manganese chloride particles, respectively.

[0117] During the smelting process, a layer of No. 2 magnesium alloy flux was evenly sprinkled on the bottom of the crucible. After the magnesium ingot was placed in, a layer of No. 2 magnesium alloy flux was also evenly sprinkled on the surface of the magnesium ingot. The resistance furnace temperature was set to 720℃. After the magnesium ingot was completely melted, the melt temperature was raised to 720℃, and Zn ingot, Mg-40Ce master alloy, and Mg-25Y master alloy were added. The mixture was held for 15 minutes. The addition of the master alloys was carried out under the protection of a mixed gas of CO2 + SF6 with a volume ratio of 99:1. The melt temperature was raised to 740℃, and anhydrous manganese chloride particles were added using a pressure hood. The mixture was stirred until it was completely melted, and a small amount of No. 5 magnesium alloy flux was placed on the surface of the melt. After holding for 10 minutes, the melt temperature was lowered to 680℃, and Mg-25Ca master alloy was added to the melt. The Mg-25Ca master alloy was pressed into the melt using a pressure hood to prevent it from floating and to ensure that it was completely melted. The melt was allowed to stand until the temperature returned to 730°C. Magnesium alloy flux No. 6 was used, and the melt was refined for 5 minutes in a CO2 + SF6 mixed atmosphere with a volume ratio of 99:1. After standing at 740°C for 15 minutes, the melt was cast into magnesium alloy ingots using an electromagnetic semi-continuous casting system. Throughout the casting process, a CO2 + SF6 mixed gas with a volume ratio of 99:1 was used for protection. The electromagnetic semi-continuous casting method used a current of 120A, and the electromagnetic frequency during electromagnetic stirring was 15Hz.

[0118] The ingots were solution treated in a muffle furnace at 480°C for 12 hours, followed by cooling in water at room temperature. The surface oxide layer of the solution-treated magnesium alloy ingots was removed, and then extrusion deformation was performed at a temperature of 300°C, an extrusion ratio of 17, and an extrusion speed of 0.2 mm / s. The mechanical properties of the alloy obtained in Example 7 are summarized in Table 14.

[0119] Table 14 shows the actual composition of near-equimolar solute-based multi-element magnesium alloys with solute element combinations of Ce, Y, Zn, Ca, and Mn.

[0120]

[0121] In summary, the magnesium alloy prepared by the high-strength soluble magnesium alloy preparation method of the present invention has higher tensile strength and yield strength than existing magnesium alloys, thus exhibiting better mechanical properties.

[0122] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations.

Claims

1. A near-equimolar solute-based multi-element alloy with high strength and toughness, characterized in that, The general chemical formula of this magnesium alloy, based on atomic percentage, is Mg. 100-x (ABCDE) x x = 0.15 at.%~1.15 at.%; where A, B, C, D, and E are the solute element composition, specifically Gd, Y, Zn, Sn, and Mn, wherein Gd, Y, Zn, Sn, and Mn are in a near equimolar ratio, and the balance is magnesium and unavoidable impurities; where x = 0.25 at.%, the specific chemical composition of the magnesium alloy is Mg. 99.75 -(GdYZnSnMn) 0.25 Its tensile strength is 348 MPa, yield strength is 337 MPa, and elongation is 5.2%; when x = 0.5 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.5 -(GdYZnSnMn) 0.5 Its tensile strength is 350 MPa, yield strength is 342 MPa, and elongation is 6.2%; when x = 1.0 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.0 -(GdYZnSnMn) 1.0 Its tensile strength is 363 MPa, yield strength is 356 MPa, and elongation is 9.3%.

2. A near-equimolar solute-based multi-element alloy with high strength and toughness, characterized in that, The general chemical formula of this magnesium alloy, based on atomic percentage, is Mg. 100-x (ABCDE) x x = 0.15 at.%~1.15 at.%; where A, B, C, D, and E are the solute element composition, specifically Gd, Y, Zn, Sn, and Zr, wherein Gd, Y, Zn, Sn, and Zr are in a near equimolar ratio, and the balance is magnesium and unavoidable impurities; where x = 0.25 at.%, the specific chemical composition of the magnesium alloy is Mg. 99.75 -(GdYZnSnZr) 0.25 Its tensile strength is 391 MPa, yield strength is 384 MPa, and elongation is 10.5%; when x = 0.5 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.5 -(GdYZnSnZr) 0.5 Its tensile strength is 405 MPa, yield strength is 395 MPa, and elongation is 8.7%; when x = 0.75 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.25 -(GdYZnSnZr) 0.75 Its tensile strength is 390 MPa, yield strength is 380 MPa, and elongation is 4.8%.

3. A near-equimolar solute-based multi-element alloy with high strength and toughness, characterized in that, The general chemical formula of this magnesium alloy, based on atomic percentage, is Mg. 100-x (ABCDE) x x = 0.15 at.%~1.15 at.%; where A, B, C, D, and E are the solute element composition, specifically Ce, Y, Zn, Ca, and Zr, wherein Ce, Y, Zn, Ca, and Zr are in a near equimolar ratio, and the balance is magnesium and unavoidable impurities; where x = 0.25 at.%, the specific chemical composition of the magnesium alloy is Mg. 99.75 -(CeYZnCaZr) 0.25 Its tensile strength is 358 MPa, yield strength is 351 MPa, and elongation is 10.3%; when x = 0.5 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.5 -(CeYZnCaZr) 0.5 Its tensile strength is 370 MPa, yield strength is 360 MPa, and elongation is 8.1%; when x = 0.75 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.25 -(CeYZnCaZr) 0.75 Its tensile strength is 365 MPa, yield strength is 353 MPa, and elongation is 7.8%.

4. A near-equimolar solute-based multi-element alloy with high strength and toughness, characterized in that, The general chemical formula of this magnesium alloy, based on atomic percentage, is Mg. 100-x (ABCDE) x x = 0.15 at.%~1.15 at.%; where A, B, C, D, and E are the solute element composition, specifically Nd, Y, Zn, Ca, and Zr, wherein Nd, Y, Zn, Ca, and Zr are in a near equimolar ratio, and the balance is magnesium and unavoidable impurities; where x = 0.25 at.%, the specific chemical composition of the magnesium alloy is Mg. 99.75 -(NdYZnCaZr) 0.25 Its tensile strength is 361 MPa, yield strength is 348 MPa, and elongation is 15.8%; when x = 0.5 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.5 -(NdYZnCaZr) 0.5 Its tensile strength is 384 MPa, yield strength is 364 MPa, and elongation is 17.7%; when x = 0.75 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.25 -(NdYZnCaZr) 0.75 Its tensile strength is 360 MPa, yield strength is 345 MPa, and elongation is 16.9%.

5. A near-equimolar solute-alloyed high-strength and high-toughness magnesium alloy, characterized in that, The general chemical formula of this magnesium alloy, based on atomic percentage, is Mg. 100-x (ABCDE) x x = 0.15 at.%~1.15 at.%; where A, B, C, D, and E are the solute element composition, specifically Sm, Y, Zn, Ca, and Zr, wherein Sm, Y, Zn, Ca, and Zr are in a near equimolar ratio, and the balance is magnesium and unavoidable impurities; where x = 0.2 at.%, the specific chemical composition of the magnesium alloy is Mg. 99.8 -(SmYZnCaZr) 0.2 Its tensile strength is 315 MPa, yield strength is 295 MPa, and elongation is 11.9%; when x = 0.4 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.6 -(SmYZnCaZr) 0.4 Its tensile strength is 340 MPa, yield strength is 318 MPa, and elongation is 19.0%; when x = 0.6 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.4 -(SmYZnCaZr) 0.6 Its tensile strength is 320 MPa, yield strength is 290 MPa, and elongation is 24.7%.

6. A near-equimolar solute-based multi-element alloy with high strength and toughness, characterized in that, The general chemical formula of this magnesium alloy, based on atomic percentage, is Mg. 100-x (ABCDE) x x = 0.15 at.%~1.15 at.%; where A, B, C, D, and E are the solute element composition, specifically La, Er, Zn, Sr, and Sc, wherein La, Er, Zn, Sr, and Sc are in a near equimolar ratio, and the balance is magnesium and unavoidable impurities; where x = 0.15 at.%, the specific chemical composition of the magnesium alloy is Mg. 99.85 -(LaErZnSrSc) 0.15 Its tensile strength is 355 MPa, yield strength is 340 MPa, and elongation is 17.9%; when x = 0.3 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.7 -(LaErZnSrSc) 0.3 Its tensile strength is 343 MPa, yield strength is 323 MPa, and elongation is 22.8%; when x = 0.6 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.4 -(LaErZnSrSc) 0.6 Its tensile strength is 352 MPa, yield strength is 333 MPa, and elongation is 20.3%.

7. A near-equimolar solute-alloyed high-strength and high-toughness magnesium alloy, characterized in that, The general chemical formula of this magnesium alloy, based on atomic percentage, is Mg. 100-x (ABCDE) x x = 0.15 at.%~1.15 at.%; where A, B, C, D, and E are the solute element composition, specifically Ce, Y, Zn, Ca, and Mn, wherein Ce, Y, Zn, Ca, and Mn are in a near equimolar ratio, and the balance is magnesium and unavoidable impurities; where x = 0.3 at.%, the specific chemical composition of the magnesium alloy is Mg. 99.7 -(CeYZnCaMn) 0.3 Its tensile strength is 300 MPa, yield strength is 290 MPa, and elongation is 15.5%; when x = 0.6 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.4 -(CeYZnCaMn) 0.6 Its tensile strength is 363 MPa, yield strength is 360 MPa, and elongation is 4.8%; when x = 0.85 at.%, the specific chemical composition of this magnesium alloy is Mg. 99.15 -(CeYZnCaMn) 0.85 Its tensile strength is 380 MPa, yield strength is 376 MPa, and elongation is 5.2%; when x = 1.15 at.%, the specific chemical composition of this magnesium alloy is Mg. 98.85 -(CeYZnCaMn) 1.15 Its tensile strength is 398 MPa, yield strength is 394 MPa, and elongation is 5.6%.

8. The method for preparing a near-equimolar solute-based multi-element alloyed high-strength and high-toughness magnesium alloy according to any one of claims 1-7, characterized in that, Includes the following steps: Raw material preparation: Based on the corresponding solute element groups, select Mg ingots, Zn ingots, Sn ingots, Mg-30Zr master alloy, Mg-25Y master alloy, Mg-25Gd master alloy, Mg-30Sm master alloy, Mg-20La master alloy, Mg-40Ce master alloy, Mg-23Nd master alloy, Mg-15Er master alloy, Mg-25Ca master alloy, Mg-10Sc master alloy, Mg-38Sr master alloy and anhydrous manganese chloride particles as raw materials in proportion; Melting and casting: The raw materials are added to an electric resistance furnace and melted and mixed at a temperature of 680℃-750℃; the molten magnesium alloy melt is cast into magnesium alloy ingots using an electromagnetic semi-continuous casting method at a temperature of 720℃-750℃. Extrusion pretreatment: Solution treatment of magnesium alloy ingots; Thermal extrusion: After solution treatment, magnesium alloy ingots are held at the extrusion temperature for 1 hour and then extruded to obtain magnesium alloy rods.

9. The method for preparing a near-equimolar solute-based multi-element alloyed high-strength and high-toughness magnesium alloy according to claim 8, characterized in that, During the smelting process, the surface of the raw material is covered with flux; and / or, the flux is selected from one or more of magnesium alloy flux No. 2, magnesium alloy flux No. 5 and magnesium alloy flux No. 6; The electromagnetic semi-continuous casting method uses a current between 100A and 130A and a frequency between 15Hz and 30Hz. The solution treatment is as follows: the magnesium alloy ingot is held at 450℃-520℃ for 12h-16h and then cooled by water quenching. The extrusion temperature of the magnesium alloy rod is between 270℃ and 350℃; and / or, the extrusion ratio of the magnesium alloy rod is between 17 and 25; and / or, the extrusion speed of the magnesium alloy rod is between 0.2 mm / s and 2 mm / s.

Images