Low-cost, high-strength, high-plasticity, corrosion-resistant, high-conductivity, low-magnesium and low-scandium aluminum alloy and preparation method thereof

Abstract

The invention relates to a low-cost, high-strength, high-plasticity, corrosion-resistant, high-conductivity, low-magnesium and low-scandium aluminum alloy and a preparation method thereof, and belongs to the technical field of aluminum-magnesium alloy development. The alloy designed by the invention comprises the following components in percentage by mass: 2.31 to 2.68 percent of Mg, 0.028 to 0.03 percent of Mn, 0.03 to 0.079 percent of Sc, 0.07 to 0.12 percent of Zr, 0.035 to 0.067 percent of Y, 0.05 to 0.075 percent of Ce, 0.081 to 0.11 percent of Ti, less than or equal to 0.06 percent of Fe, less than or equal to 0.05 percent of Si and the balance of Al and inevitable impurities. According to the invention, an H111-state product with excellent comprehensive performance is obtained through simple smelting casting and hot rolling under the synergistic effect of the components by introducing an ultra-low amount of Sc and cooperating with other proper amounts of components. The component design is reasonable, the preparation process is simple and controllable, the comprehensive performance of the obtained product is excellent, and industrial application is facilitated.

Description

TECHNICAL FIELD

[0001] The application relates to a low-cost high-strength plasticity corrosion-resistant high-conductivity low-magnesium low-scandium aluminum alloy and a preparation method thereof, and belongs to the technical field of aluminum-magnesium alloy development. BACKGROUND

[0002] Aluminum-magnesium alloys have the advantages of low density, high specific strength, green recycling, excellent corrosion resistance and weldability, and are widely used in fields such as aerospace, electronics and power and ships. The aluminum-magnesium alloy belongs to a non-heat-treatable strengthening alloy, and the strength of the aluminum-magnesium alloy is mainly improved through solid solution strengthening of Mg elements and work hardening. However, although increasing the magnesium content can improve the strength of the aluminum-magnesium alloy, the electrical conductivity and plasticity of the alloy are reduced, and magnesium-rich phases are easily precipitated, increasing the intergranular corrosion sensitivity. Therefore, the existing aluminum-magnesium alloy is difficult to achieve the simultaneous improvement of the strength, plasticity, electrical conductivity and corrosion resistance of the alloy.

[0003] Among all the micro-alloying elements, the scandium element has the most significant effect on improving the performance of aluminum alloys. Compared with traditional aluminum-magnesium alloys, a new type of aluminum-magnesium-scandium alloy developed through scandium micro-alloying has more excellent comprehensive performance and is a new generation of lightweight and high-quality structural material. However, scandium is very expensive, and the lowest scandium addition reported at present is all greater than or equal to 0.10% (mass fraction), which undoubtedly increases the manufacturing cost of the aluminum-magnesium alloy. In addition, the aluminum-magnesium-scandium alloys reported at present are all medium-high magnesium content aluminum-magnesium-scandium alloys, which have high material strength but low electrical conductivity and plasticity and are sensitive to intergranular corrosion. At present, there is no report on a low-magnesium ultra-low-scandium aluminum-magnesium-scandium alloy. For example, patent CN101941122A relates to a corrosion-resistant aluminum-magnesium-scandium alloy with a welding wire. The composition of the welding wire includes Mg, the weight percentage of which is 3.0-5.0%; Zr, the weight percentage of which is 0.1-0.2%; Sc, the weight percentage of which is 0.1-0.2%; Mn, the weight percentage of which is 0.2-0.3%; Ti, the weight percentage of which is 0.05-0.15%; Cr, the weight percentage of which is 0.05-0.25%; Ce, the weight percentage of which is 0.01-0.05%; and Y, the weight percentage of which is 0.01. The patent does not involve the electrical conductivity, corrosion resistance and elongation of the product, and the elongation needs to be further improved. In summary, how to reduce the material cost and simultaneously improve the strength, plasticity, electrical conductivity and intergranular corrosion resistance of the alloy is a technical problem to be solved at present.

[0004] Scandium in aluminum alloys mainly exists in the form of micron-sized primary Al3Sc and nano-sized secondary Al3Sc particles. While micron-sized primary Al3Sc can refine the casting structure, its large size easily leads to stress concentration and reduces alloy plasticity. Nano-sized secondary Al3Sc, through strong pinning of dislocations and grain boundaries, can produce significant substructure strengthening and Vanoan strengthening, thereby significantly improving alloy strength. However, this requires a scandium addition of at least 0.55% (mass fraction), which greatly increases the alloy manufacturing cost. This invention employs composite microalloying technology. Without sacrificing strength, to reduce the effective scandium addition, a suitable amount of Zr is added to partially replace Sc atoms in Al3Sc, forming nano-sized secondary Al3(Sc,Zr) particles. However, it was found that the increase of Zr increases electron scattering ability and reduces the alloy's electrical conductivity. Summary of the Invention

[0005] This invention addresses the shortcomings of existing technologies by incorporating previous research and design to prepare a low-cost, high-strength, ductile, corrosion-resistant, high-conductivity, low-magnesium, and low-scandium aluminum alloy. Based on the addition of low magnesium and low scandium, this invention achieves simultaneous improvements in strength, ductility, corrosion resistance, and electrical conductivity. Furthermore, its preparation process is simple, short-process, economical, and efficient.

[0006] This invention aims to simultaneously improve the strength, plasticity, electrical conductivity, and intergranular corrosion resistance of alloys while reducing alloy costs. This is achieved primarily through the following four aspects: 1. Focusing on Al-(2.3~2.6)Mg low-magnesium-content aluminum-magnesium alloys, the low magnesium content design reduces the difficulty of smelting and casting, decreases the enrichment of intergranular magnesium and the formation of magnesium-rich phases, and reduces electron scattering, thus improving intergranular corrosion resistance and electrical conductivity; 2. Employing extremely low amounts of Sc element (0.03-0.079% by mass fraction), this extremely low content avoids the presence of primary Al3Sc micron-sized particles, reduces stress concentration sites, and improves alloy plasticity; 3. Combining multi-element composite microalloying technology, appropriate amounts of microalloying elements such as Y, Zr, and Ti are added, along with suitable heat treatment processes, to promote the replacement of Sc elements in secondary Al3Sc nanoparticles by these trace elements as much as possible, thereby forming effective multi-element microalloyed nano-reinforcing particles to achieve the goal of improving the strength of aluminum-magnesium alloys. 4. By adding Ce element, which is easy to combine with appropriate amount of Fe impurity element in aluminum matrix through composite microalloying, the formation of Fe-rich intermetallic compounds is promoted, the supersaturation of Fe in the matrix is ​​reduced, the matrix is ​​purified, the probability of electron scattering is reduced, and thus the goal of increasing conductivity is achieved.

[0007] The alloy preparation of this invention adopts a short process, namely: alloy melting and casting into ingots, heat treatment and annealing before hot rolling to replace ingot homogenization, and direct hot rolling into H111 plates after heat treatment.

[0008] This invention discloses a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy, comprising the following components by weight percentage:

[0009] Mg 2.31-2.68%;

[0010] Mn 0.028-0.03%;

[0011] Sc 0.03~0.079%;

[0012] Zr 0.07-0.12%;

[0013] Y 0.035-0.067%;

[0014] Ce 0.05~0.075%;

[0015] Ti 0.081~0.11%

[0016] Fe ≤ 0.06%;

[0017] Si is less than or equal to 0.05%;

[0018] The balance consists of Al and unavoidable impurities.

[0019] When the product obtained by this invention is in the H111 state, its average tensile strength is greater than 265 MPa, its average elongation is greater than 20%, and its electrical conductivity is greater than 40% IACS.

[0020] This invention discloses a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy, which comprises the following components by weight percentage:

[0021] Mg 2.31-2.35%;

[0022] Mn 0.028~0.03%;

[0023] Sc 0.03~0.035%;

[0024] Zr 0.07~0.08%;

[0025] Y 0.035-0.04%;

[0026] Ce 0.05~0.055%;

[0027] Ti 0.081~0.085%

[0028] Fe ≤ 0.06%;

[0029] Si is less than or equal to 0.05%;

[0030] The balance consists of Al and unavoidable impurities; the resulting H111 alloy exhibits a yield strength greater than 210 MPa, a tensile strength greater than 265 MPa, an elongation greater than 20%, and an electrical conductivity greater than 41.7% IACS. This method achieves the use of ultra-low Sc and yields an H111 alloy with high strength, high elongation, and high electrical conductivity.

[0031] To further improve the strength of the product, while minimizing the rapid decline in conductivity and elongation, the present invention also incorporates the following components:

[0032] The designed components consist of the following ingredients by weight percentage:

[0033] Mg 2.65-2.68%;

[0034] Mn 0.028~0.03%;

[0035] Sc 0.075~0.079%;

[0036] Zr 0.11~0.12%;

[0037] Y 0.065-0.067%;

[0038] Ce 0.07~0.075%;

[0039] Ti 0.1~0.11%

[0040] Fe ≤ 0.06%;

[0041] Si is less than or equal to 0.05%;

[0042] The balance consists of Al and unavoidable impurities; the resulting H111 alloy has a yield strength of 223 ± 4 MPa, a tensile strength of 278 ± 1 MPa, an elongation of 20.2 ± 2.2%, and an electrical conductivity of 40.5 ± 0.1% IACS. This invention also provides, for the first time, an alternative solution that achieves a strength increase of over 3.7% (compared to ultra-low scandium solutions) while reducing electrical conductivity by less than 3.5%.

[0043] This invention discloses a method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy, comprising the following steps:

[0044] Step 1: Smelting and Casting

[0045] After the melting furnace is heated to 760-775℃, pure aluminum and covering agent are added according to the design composition. After standing for 30-50 minutes, Al-Ti, Al-Sc, Al-Zr, Al-Ce, Al-Y and Al-Mn master alloys are added. After standing for 10-30 minutes, the first slag removal and degassing are performed. Then, after stabilizing the temperature to 720-750℃, magnesium is added. After standing for 2-5 minutes until the magnesium melts, the second degassing and slag removal are performed. After standing for another 5-15 minutes, the furnace is opened to remove the slag and the alloy is cast into a water-cooled copper mold. After casting, the alloy is water-quenched to obtain the alloy ingot.

[0046] Step Two: Hot Rolling

[0047] Before rolling, the alloy ingot is milled. After milling, it is held at 460-480℃ for 3-5 hours. Then, it is hot rolled in 6-8 passes with a total deformation of >75%. The initial rolling temperature is maintained at 400-430℃ and the final rolling temperature is controlled at 280-320℃ to obtain the H111 alloy.

[0048] This invention discloses a method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy. In step one, the covering agent is composed of potassium chloride and magnesium chloride.

[0049] This invention discloses a method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy. In step one, the method used for the first slag and gas removal includes wrapping hexachloroethane in aluminum foil and pressing it in with a bell jar.

[0050] This invention discloses a method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy. In step two, when the thickness of the alloy ingot is 28-30 mm, it is hot-rolled to a thickness of 6-8 mm.

[0051] This invention discloses a method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy. After hot rolling, the alloy has an elongated deformed fiber substructure.

[0052] This invention discloses a method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy, wherein the hot-rolled alloy contains Al3(Sc,Zr,Ti,Y) nanoparticles.

[0053] Studies have found that, using the composition and preparation process of this invention, Al3(Sc,Zr,Ti,Y) nanoparticles are uniformly distributed in the alloy.

[0054] In this invention, Al3(Sc,Zr,Ti,Y) nanoparticles are nanoparticles formed in a secondary manner. Attached Figure Description

[0055] Figure 1The microstructure of the H111 alloy obtained in Example 1 is shown in the following figures: (a) is a TEM image; (b) is a dark field and electron diffraction pattern of the nanoparticle superlattice; (c) is a room temperature tensile fracture characterization image; (d) is a HAADF and atomic-level super energy spectrum of the nanoparticles; and (e) is a scanning electron microscope backscattered electron image and the energy spectrum results of phases A and B in the figure. Detailed Implementation

[0056] Comparative Example 1

[0057] The designed alloy composition is shown in Table 1 for Alloy 1;

[0058] Its preparation process is as follows:

[0059] Step 1: Smelting and Casting

[0060] After stabilizing the temperature to 780℃ using a pit-type resistance furnace, pure aluminum and a covering agent (potassium chloride and magnesium chloride in a 1:1 mass ratio) were added. After standing for 30 minutes, Al-Mn master alloy was added. After standing for 10 minutes, the first slag and degassing process was performed (method: hexachloroethane (approximately 0.5% of the total weight of materials in the furnace) was wrapped in aluminum foil and pressed in with a bell jar). After stabilizing the temperature to 760℃, magnesium was added. After standing for 3 minutes until the magnesium melted, the second degassing and slag removal were performed. After standing for about 3 minutes, the furnace was opened to remove the slag and the alloy was cast into a water-cooled copper mold (cooling rate of 200℃ / s). Half a minute after casting, the mold was removed and the alloy was water-quenched to obtain an alloy ingot with a thickness of 30mm.

[0061] Step Two: Hot Rolling

[0062] Before rolling, the alloy ingot was milled, and then held at 480℃ for 4 hours. After that, it was hot rolled in 8 passes from 30mm to about 7mm, with a total deformation of 76.6%. The initial rolling temperature was maintained at 420℃, and the final rolling temperature was controlled at 300℃. The properties of the resulting product are shown in Table 2.

[0063] Comparative Example 2

[0064] The designed alloy composition is shown in Table 1 for alloy 2;

[0065] Its preparation process is as follows:

[0066] Step 1: Smelting and Casting

[0067] After stabilizing the temperature to 780℃ using a pit-type resistance furnace, pure aluminum and a covering agent (potassium chloride and magnesium chloride in a 1:1 mass ratio) were added. After standing for 30 minutes, Al-Ti, Al-Sc, Al-Zr, and Al-Mn master alloys were added. After standing for 30 minutes, the first slag and degassing process was performed (method: hexachloroethane (approximately 0.5% of the total weight of materials in the furnace) was wrapped in aluminum foil and pressed in with a bell jar). After stabilizing the temperature to 760℃, magnesium was added. After standing for 5 minutes until the magnesium melted, the second degassing and slag removal process was performed. After standing for about 3 minutes, the furnace was opened to remove the slag and the alloy was cast into a water-cooled copper mold (cooling rate of 200℃ / s). Half a minute after casting, the mold was removed and the alloy was water-quenched to obtain an alloy ingot with a thickness of 29mm.

[0068] Step Two: Hot Rolling

[0069] Before rolling, the alloy ingot was milled, and then held at 480℃ for 4 hours. After that, it was hot rolled in 8 passes from 29mm to about 6.5mm, with a total deformation of 77.6%. The initial rolling temperature was maintained at 420℃, and the final rolling temperature was controlled at 300℃. The properties of the resulting product are shown in Table 2.

[0070] Comparative Example 3

[0071] The designed alloy composition is shown in Table 1 for alloy 3;

[0072] Its preparation process is as follows:

[0073] Step 1: Smelting and Casting

[0074] After stabilizing the temperature to 780℃ using a pit-type resistance furnace, pure aluminum and a covering agent (potassium chloride and magnesium chloride in a 1:1 mass ratio) were added. After standing for 30 minutes, Al-Ce, Al-Y, and Al-Mn master alloys were added. After standing for 30 minutes, the first slag and degassing process was performed (method: hexachloroethane (approximately 0.5% of the total weight of materials in the furnace) was wrapped in aluminum foil and pressed in with a bell jar). After stabilizing the temperature to 760℃, magnesium was added. After standing for 5 minutes until the magnesium melted, the second degassing and slag removal process was performed. After standing for about 3 minutes, the furnace was opened to remove the slag and the alloy was cast into a water-cooled copper mold (cooling rate of 200℃ / s). Half a minute after casting, the mold was removed and the alloy was water-quenched to obtain an alloy ingot with a thickness of 30mm.

[0075] Step Two: Hot Rolling

[0076] Before rolling, the alloy ingot was milled, and then held at 480℃ for 4 hours. After that, it was hot rolled in 8 passes from 30mm to about 7mm, with a total deformation of 76.6%. The initial rolling temperature was maintained at 420℃, and the final rolling temperature was controlled at 300℃. The properties of the resulting product are shown in Table 2.

[0077] Example 1

[0078] The designed alloy composition is shown in Table 1 for alloy 4;

[0079] Its preparation process is as follows:

[0080] Step 1: Smelting and Casting

[0081] After stabilizing the temperature to 780℃ using a pit-type resistance furnace, pure aluminum and a covering agent (potassium chloride and magnesium chloride in a 1:1 mass ratio) were added. After standing for 30 minutes, Al-Ti, Al-Sc, Al-Zr, Al-Ce, Al-Y, and Al-Mn master alloys were added. After standing for 30 minutes, the first slag and degassing process was performed (method: hexachloroethane (approximately 0.5% of the total weight of materials in the furnace) was wrapped in aluminum foil and pressed in using a bell jar). After stabilizing the temperature to 760℃, magnesium was added. After standing for 5 minutes until the magnesium melted, the second degassing and slag removal process was performed. After standing for about 3 minutes, the furnace was opened to remove the slag and the alloy was cast into a water-cooled copper mold (cooling rate of 200℃ / s). Half a minute after casting, the mold was removed and the alloy was water-quenched to obtain an alloy ingot with a thickness of 29mm.

[0082] Step Two: Hot Rolling

[0083] Before rolling, the alloy ingot was milled, and then held at 480℃ for 4 hours. After that, it was hot rolled in 8 passes from 30mm to about 7mm, with a total deformation of 76.6%. The initial rolling temperature was maintained at 420℃, and the final rolling temperature was controlled at 300℃. The properties of the resulting product are shown in Table 2.

[0084] Example 2

[0085] The designed alloy composition is shown in Table 1 for alloy 5;

[0086] The preparation process is the same as in Example 1, and the performance of the resulting product is shown in Table 2.

[0087] Example 3

[0088] The designed alloy composition is shown in Table 1 for alloy 6;

[0089] The preparation process is the same as in Example 1, and the performance of the resulting product is shown in Table 2.

[0090] Example 4

[0091] The designed alloy composition is shown in Table 1 for alloy 7;

[0092] The preparation process is the same as in Example 1, and the performance of the resulting product is shown in Table 2.

[0093]

[0094]

[0095] Table 2 shows that, compared to Alloy 1, Alloy 2, through Sc, Zr, and Ti ternary composite microalloying, exhibits increased yield strength and tensile strength by 69 MPa and 60 MPa, respectively. However, its plasticity and electrical conductivity significantly decreased. This indicates that Sc, Zr, and Ti microalloying is effective in improving the strength of aluminum-magnesium alloys, but its addition increases electron scattering, resulting in an electrical conductivity of only 36.5 ± 0.3 and a decrease in plasticity from 22.9 ± 3.3 to 17.2 ± 2.0. Furthermore, the intergranular corrosion level remained essentially unchanged. After Y and Ce binary composite microalloying, the yield strength and tensile strength of the alloy increased by 23 MPa and 41 MPa, respectively, with only a slight decrease in plasticity and a significant increase in electrical conductivity, from 38.1 ± 0.2 to 42.5 ± 0.2. The intergranular corrosion rating improved to level 1, indicating that while the addition of Y and Ce has a slightly weaker strength effect than the ternary composite microalloying of Sc, Zr, and Ti, it significantly improves the alloy's electrical conductivity and intergranular corrosion resistance. Based on the performance results of alloys 2 and 3, alloys 4-7 were designed. After appropriate amounts of Sc, Zr, Y, Ce, and Ti pentagonal composite microalloying, the yield strength and tensile strength of the alloys were significantly improved, while the elongation and electrical conductivity remained at a high level. The yield strength, tensile strength, elongation, electrical conductivity, and intergranular corrosion resistance of the pentagonal microalloyed alloys reached 213-223 MPa, 269-278 MPa, 20.2-21.1%, 40.9-41.9% IACS, and level 1, exhibiting high strength, plasticity, high electrical conductivity, and corrosion resistance. Among the four microalloyed alloys, the pentagonal microalloying alloy has the best overall performance. It has the advantages of high strength, high plasticity, high conductivity and corrosion resistance, and has great potential application value in the fields of ships and marine facilities, power transmission structures and so on.

[0096] To reveal the high strength, high plasticity, high electrical conductivity, and corrosion resistance of the pentagonal microalloyed alloy, its microstructure was observed, and the results are as follows: Figure 1 As shown.

[0097] Depend on Figure 1 It can be seen that after hot rolling, the alloy still retains the tensile deformation substructure. Figure 1 (a)) The alloy contains a large number of dislocations, and magnified observation reveals that the high-density nanoscale particles strongly pin the dislocations. Figure 1(b) This is why pentagonal microalloying can improve the strength of the alloy. Furthermore, electron diffraction patterns show that its crystal structure is the same as that of secondary Al3Sc particles. HAADF and atomic-level super-energy dispersive spectroscopy characterization revealed that this particle is formed by replacing some Sc with Zr, Ti, and Y atoms on the basis of secondary Al3Sc particles, forming nanoscale Al3(Sc,Zr,Ti,Y). The replacement of Zr, Ti, and Y atoms increases the density of the secondary nanoparticles. Simultaneously, due to the influence of different element diffusion coefficients, its thermal stability is higher than that of Al3Sc particles, which is why alloy 4 has the highest strength. In addition, the formation of high-density, fine, multi-element microalloyed nanoparticles reduces stress concentration in coarse particles, resulting in more uniform deformation. After room temperature stretching, the alloy exhibits a fine dimple morphology on the fracture surface, showing ductile transgranular fracture. Figure 1 (c) Therefore, the alloy still maintains a high elongation of >20%, and due to its fine grain size, it is less susceptible to grain boundary corrosion and intergranular corrosion. The role of Ce in the alloy can be discussed from... Figure 1 (e) It is evident that the alloy contains a small amount of gray Y and Ce-rich phases and white Y, Fe, and Ce-rich phases. This indicates that Y and Ce readily form Y and Ce-rich non-equilibrium phases in the aluminum alloy, and these phases can promote the simultaneous precipitation of Fe impurity elements, reduce the supersaturation of Fe in the matrix, facilitate matrix purification, and thus reduce the probability of electron scattering, thereby improving the alloy's electrical conductivity. In summary, due to the composite addition of the five microalloying elements Sc, Zr, Y, Ce, and Ti, Al3(Sc,Zr,Ti,Y) nanoparticles are formed in the matrix. Compared to the previous secondary Al3Sc particles, the addition of Sc can be reduced because Zr, Ti, and Y atoms replace the expensive Sc atoms, thus achieving cost savings. At the same time, the replacement of Zr, Ti, and Y atoms increases the density of Al3(Sc,Zr,Ti,Y) nanoparticles, reduces their particle size, and promotes uniform alloy slip, thus achieving the goal of low cost and high strength and plasticity.

Claims

1. A low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy, characterized in that: By weight percentage, it includes the following components: Mg 2.31-2.68%; Mn 0.028-0.03%; Sc 0.03~0.079%; Zr 0.07-0.12%； Y 0.035-0.067%； Ce 0.05~0.075%; Ti 0.081~0.11%; Fe ≤ 0.06%; Si is less than or equal to 0.05%; The balance consists of Al and unavoidable impurities.

2. The low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy according to claim 1, characterized in that: When the obtained product is in the H111 state, its average tensile strength is greater than 265 MPa, its average elongation is greater than 20%, and its electrical conductivity is greater than 40% IACS.

3. The low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy according to claim 1, characterized in that: The low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy comprises, by weight percentage, the following components: Mg 2.31-2.35%; Mn 0.028~0.03%; Sc 0.03~0.035%; Zr 0.07~0.08%； Y 0.035-0.04%； Ce 0.05~0.055%; Ti 0.081~0.085%; Fe ≤ 0.06%; Si is less than or equal to 0.05%; The balance is Al and unavoidable impurities; the resulting H111 alloy has a yield strength greater than 210 MPa, a tensile strength greater than 265 MPa, an elongation greater than 20%, and an electrical conductivity greater than 41.7% IACS.

4. The low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy according to claim 1, characterized in that: The low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy comprises, by weight percentage, the following components: Mg 2.65-2.68%; Mn 0.028~0.03%; Sc 0.075~0.079%; Zr 0.11~0.12%； Y 0.065-0.067%； Ce 0.07~0.075%; Ti 0.1~0.11%; Fe ≤ 0.06%; Si is less than or equal to 0.05%; The balance is Al and unavoidable impurities; the resulting H111 alloy has a yield strength of 223 ± 4 MPa, a tensile strength of 278 ± 1 MPa, an elongation of 20.2 ± 2.2%, and an electrical conductivity of 40.5 ± 0.1% IACS.

5. A method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy as described in any one of claims 1-4, characterized in that, Includes the following steps: Step 1: Smelting and Casting After the melting furnace is heated to 760-775℃, pure aluminum and covering agent are added according to the design composition. After standing for 30-50 minutes, Al-Ti, Al-Sc, Al-Zr, Al-Ce, Al-Y and Al-Mn master alloys are added. After standing for 10-30 minutes, the first slag removal and degassing are performed. Then, after stabilizing the temperature to 720-750℃, magnesium is added. After standing for 2-5 minutes until the magnesium melts, the second degassing and slag removal are performed. After standing for another 5-15 minutes, the furnace is opened to remove the slag and the alloy is cast into a water-cooled copper mold. After casting, the alloy is water-quenched to obtain the alloy ingot. Step Two: Hot Rolling Before rolling, the alloy ingot is milled. After milling, it is held at 460-480℃ for 3-5 hours. Then, it is hot rolled in 6-8 passes with a total deformation of >75%. The initial rolling temperature is maintained at 400-430℃ and the final rolling temperature is controlled at 280-320℃ to obtain the H111 alloy.

6. The method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy according to claim 5, characterized in that: In step one, the covering agent consists of potassium chloride and magnesium chloride; In step one, the method used for the first slag and gas removal includes wrapping hexachloroethane in aluminum foil and pressing it in with a bell jar.

7. The method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy according to claim 5, characterized in that: In step two, when the thickness of the alloy ingot is 28-30mm, it is hot rolled to a thickness of 6-8mm.

8. The method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy according to claim 5, characterized in that: After hot rolling, the alloy has an elongated deformed fiber substructure.

9. The method for preparing a low-cost, high-strength, ductile, corrosion-resistant, highly conductive, low-magnesium, and low-scandium aluminum alloy according to claim 5, characterized in that: The hot-rolled alloy contains Al3(Sc,Zr,Ti,Y) nanoparticles.

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