A method for preparing a lightweight high-strength aluminum alloy for power equipment

Abstract

The application relates to a preparation method of a lightweight high-strength aluminum alloy for power equipment, which mainly comprises the steps of determining alloy components, smelting, heat treatment, cold processing and the like. First, smelting is carried out in a vacuum induction smelting furnace, and the element content in the aluminum alloy, such as lithium, magnesium, zinc, copper, manganese and titanium, is regulated. Argon protection is adopted in the smelting process, so that the lithium content in the alloy is ensured to be within a proper range; the heat treatment process comprises solid solution treatment, quenching and aging treatment; the cold processing process comprises cold rolling, stretching and cold extrusion; through regulation of the alloy components and adoption of proper process parameters, the lightweight high-strength aluminum alloy prepared by the application can be widely applied to power equipment, meets the lightweight and high-strength requirements, and has high practical value.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy preparation, and more specifically to a method for preparing a lightweight, high-strength aluminum alloy for use in power equipment. Background Technology

[0002] Electrical equipment plays a vital role in modern society, and the selection of materials for equipment such as transmission lines and transformers is particularly crucial. Traditional metal materials such as copper and steel are widely used in electrical equipment, but these materials often have disadvantages such as heavy weight and high cost, which not only increase the load on the equipment but also limit the improvement of equipment performance.

[0003] In recent years, aluminum alloys have gained increasing attention in the field of power equipment due to their excellent properties such as lightweight, high strength, and good electrical conductivity. However, aluminum alloys currently on the market still have shortcomings in terms of strength and corrosion resistance. For example, aluminum alloys are easily damaged under high loads and have a short service life, thereby increasing the operation and maintenance costs of power equipment.

[0004] To address the aforementioned issues, it is necessary to develop a lightweight aluminum alloy material with excellent strength, low density, good corrosion resistance, and electrical conductivity, along with its preparation method. Developing a high-performance, low-cost, and easily mass-producible lightweight high-strength aluminum alloy material is of great significance, as it can promote the performance improvement of power equipment and the efficient utilization of electrical energy.

[0005] Therefore, the present invention aims to provide a lightweight, high-strength aluminum alloy material for power equipment and a method for preparing the same, in order to solve the aforementioned problems in the application of aluminum alloys in power equipment in the prior art. Summary of the Invention

[0006] To address the problems in the application of aluminum alloys in power equipment in the prior art, this invention provides a lightweight, high-strength aluminum alloy material for power equipment and its preparation method, as detailed below:

[0007] A method for preparing a lightweight, high-strength aluminum alloy for power equipment includes the following steps:

[0008] S1. Determine the alloy composition, including Al, Mg, Zn, Ti, Li, Cu, and Mn;

[0009] Al, as a matrix element, provides the alloy with low density as well as good electrical and thermal conductivity;

[0010] Mg is a commonly used alloy strengthening element. Adding an appropriate amount of magnesium can significantly improve the strength of materials, while reducing the density of alloys and further reducing weight.

[0011] Zn is also a commonly used alloy strengthening element. The addition of zinc can improve the strength of aluminum alloys and at the same time improve the material's resistance to stress corrosion.

[0012] Ti, as a trace element in alloys, acts as a grain refiner. The addition of titanium can improve the microstructure of materials and enhance the fatigue performance, stress corrosion resistance, and oxidation resistance of alloys.

[0013] As a light alloying element, the addition of lithium can reduce the alloy density, enhance the heat treatment strengthening effect, increase plasticity and toughness, and at the same time improve the strain hardening rate and creep properties of the alloy.

[0014] The alloy is smelted according to its composition, using a vacuum induction melting furnace and argon gas for protection. During the smelting process, the lithium content of the aluminum alloy is periodically sampled and analyzed and controlled within a certain range. Controlling the lithium content can effectively reduce the density of the aluminum alloy, making the final aluminum alloy product lighter. On the other hand, lithium can form strengthening phases with other alloying elements such as Mg and Cu, further improving the strength of the material.

[0015] S2. Heat treatment: This includes the following sub-steps:

[0016] S201 Solution treatment: The aluminum alloy is heated to the solution treatment temperature and held for a period of time; the alloy is first subjected to solution treatment to eliminate the as-cast structure, uniformly distribute the alloying elements, and prepare the structure.

[0017] S202, Quenching: Rapidly cooling the aluminum alloy from the solution treatment temperature to room temperature to form a supersaturated solid solution; rapid cooling can prevent the supersaturated solid solution between the crystal lattices from forming a eutectic phase or other unstable phases, which would have an adverse effect on the alloy's properties.

[0018] S203 is used to age quenched aluminum alloys, causing supersaturated solid solutions to precipitate and improving the strength and hardness of the alloy.

[0019] S3. Cold working: This includes the following sub-steps:

[0020] S301, Cold Rolling: The aged aluminum alloy is cold rolled. By controlling the thickness reduction rate between 40% and 60%, the grain structure and microstructure of the aluminum alloy are improved to enhance the strength of the alloy. The rolling speed during the cold rolling process is set at 200-400 m / min to maintain the rolling quality.

[0021] The cold rolling process allows for the adjustment of the thickness and width of aluminum alloy sheets, strips, and foils, while simultaneously improving surface quality and dimensional accuracy, and enhancing the tensile and bending strength of the alloy. By controlling the thickness reduction rate during rolling, the grain size and shape within the alloy can be adjusted to some extent, thereby optimizing its mechanical properties and plasticity. The cold rolling process complements the heat treatment process; by flexibly controlling both processes, it is possible to reduce the alloy's density while simultaneously improving its strength and toughness.

[0022] S302, Stretching: The cold-rolled aluminum alloy is stretched to plastically process the alloy. The stretching deformation is 5-10% to further optimize its grain structure while maintaining good plasticity. The stretching speed is 25-50 mm / min to obtain a suitable stretching effect.

[0023] Cold drawing of aluminum alloys can increase the slenderness of the alloy material, thereby improving the tensile strength and dimensional accuracy of the alloy wire. By adjusting parameters such as drawing speed and number of passes, it is possible to rationally select whether intermediate annealing is required and, if so, the specific temperature and time for annealing, further optimizing the mechanical properties and plasticity.

[0024] S303, Cold Extrusion: Cold extrusion involves cold extruding the stretched aluminum alloy to further improve its microstructure and performance. During the extrusion process, the extrusion deformation is set at 10%-15%, and the extrusion speed is controlled at 10-20 mm / s to achieve the lightweight and high-strength target required for power equipment.

[0025] Furthermore, the mass percentages of each element in S1 are: Mg 0.6–0.8%, Zn ≤0.05%, Ti ≤0.08%, Li ≤0.1%, Cu ≤0.03%, Mn 0.4–0.6%, and the remainder being Al.

[0026] Furthermore, the melting temperature in S1 is 700–750℃, the melting time is 2–4h, the argon flow rate is 4–6L / min, and the argon pressure is 0.1–0.3MPa.

[0027] Furthermore, the process parameters for the S201 solution treatment are: solution treatment temperature of 400–550℃ and solution treatment time of 0.5–2h.

[0028] Furthermore, the aging treatment temperature in S203 is 150–250℃, and the aging holding time is 5–20h.

[0029] Furthermore, in the S301 cold rolling process, the rolling passes are 3 times, and an intermediate annealing treatment is performed after each rolling pass. The annealing temperature is controlled at 200-300℃, and the holding time is 1-2 hours.

[0030] Furthermore, the stretching speed of S302 is 100-20 mm / min.

[0031] Furthermore, the extrusion deformation of S303 is set to 10% to 12%, and the extrusion speed is controlled at 10 to 15 mm / s.

[0032] Furthermore, the vacuum degree of the vacuum induction melting furnace is 1 to 50 Pa.

[0033] Beneficial effects:

[0034] This invention provides a lightweight, high-strength aluminum alloy material for power equipment and its preparation method, which has the following beneficial effects:

[0035] (1) By optimizing the alloy composition and preparation process, the strength, plasticity and toughness of aluminum alloys have been improved, which meets the demand of power equipment for high-strength and lightweight aluminum alloy materials.

[0036] (2) The present invention uses a vacuum induction melting furnace and argon protection, which effectively reduces the loss of lithium volatilization during the melting process, ensures the stability of lithium content, and thereby improves the mechanical properties of the alloy material.

[0037] (3) The heat treatment process provided by the present invention realizes the solution treatment, quenching and aging treatment of aluminum alloy, so that the supersaturated solid solution in the alloy precipitates, enhances the strength and hardness of the alloy, and reduces its internal stress.

[0038] (4) The present invention provides a cold working method, including steps such as cold rolling, stretching and cold extrusion, which further optimizes the microstructure and properties of the alloy, so that the aluminum alloy has good tensile strength, bending strength and plasticity to a certain extent.

[0039] (5) The process parameters and vacuum settings provided by the present invention have good feasibility and practicality, which enables excellent control over the preparation process of lightweight high-strength aluminum alloys and improves the performance and application range of alloy products.

[0040] In summary, the present invention provides a lightweight, high-strength aluminum alloy material for power equipment and its preparation method, which is of great practical significance for ensuring the safe and stable operation of power equipment, improving production efficiency and reducing energy consumption. Detailed Implementation

[0041] To enhance understanding of the present invention, the present invention will be further described in detail below with reference to embodiments. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0042] Example 1

[0043] A method for preparing a lightweight, high-strength aluminum alloy material for power equipment, comprising the following steps:

[0044] S1. Determine the alloy composition according to the table below:

[0045] alloy Mg Zn Ti Li Cu Mn Al mass percentage / % 0.7％ 0.04％ 0.06％ 0.08％ 0.02％ 0.5％ the remaining

[0046] S2. A vacuum induction melting furnace was used for melting at a temperature of 730℃ for 3 hours, with an argon flow rate of 5 L / min and an argon pressure of 0.2 MPa. During the melting process, lithium content was periodically sampled and analyzed to ensure it remained within acceptable limits.

[0047] S3. Heat the aluminum alloy to the solution treatment temperature of 500℃, hold for 1 hour, and then rapidly cool to room temperature;

[0048] S4. The quenched aluminum alloy is subjected to aging treatment at a temperature of 225℃ and a holding time of 10h.

[0049] S5. During cold rolling, the thickness reduction rate is controlled at 50%, the rolling passes are 3, and intermediate annealing is performed after each rolling pass. The annealing temperature is 250℃ and the holding time is 1.5h.

[0050] S6. The cold-rolled aluminum alloy is subjected to stretching treatment with a stretching deformation of 7.5% and a stretching speed of 26 mm / min.

[0051] S7. The stretched aluminum alloy is cold extruded, with the extrusion deformation set at 11% and the extrusion speed controlled at 12 mm / s.

[0052] Example 2:

[0053] S1. Determine the alloy composition according to the table below:

[0054] alloy Mg Zn Ti Li Cu Mn Al mass percentage / % 0.7％ 0.04％ 0.06％ 0.08％ 0.02％ 0.5％ the remaining

[0055] S2. A vacuum induction melting furnace was used for melting at a temperature of 750℃ for 2.5 hours, with an argon flow rate of 6 L / min and an argon pressure of 0.25 MPa. During the melting process, lithium content was periodically sampled and analyzed to ensure it remained within acceptable limits.

[0056] S3. Heat the aluminum alloy to the solution treatment temperature of 500℃, hold for 1 hour, and then rapidly cool to room temperature;

[0057] S4. The quenched aluminum alloy is subjected to aging treatment at a temperature of 225℃ and a holding time of 10h.

[0058] S5. During cold rolling, the thickness reduction rate is controlled at 50%, the rolling passes are 3, and intermediate annealing is performed after each rolling pass. The annealing temperature is 300℃ and the holding time is 1h.

[0059] S6. The cold-rolled aluminum alloy is subjected to stretching treatment with a stretching deformation of 7.5% and a stretching speed of 27 mm / min.

[0060] S7. The stretched aluminum alloy is cold extruded, with the extrusion deformation set at 11% and the extrusion speed controlled at 12 mm / s.

[0061] Example 3:

[0062] S1. Determine the alloy composition according to the table below:

[0063] alloy Mg Zn Ti Li Cu Mn Al mass percentage / % 0.7％ 0.04％ 0.06％ 0.08％ 0.02％ 0.5％ the remaining

[0064] S2. A vacuum induction melting furnace was used for melting at a temperature of 750℃ for 2.5 hours, with an argon flow rate of 6 L / min and an argon pressure of 0.25 MPa. During the melting process, lithium content was periodically sampled and analyzed to ensure it remained within acceptable limits.

[0065] S3. Heat the aluminum alloy to the solution treatment temperature of 500℃, hold for 1 hour, and then rapidly cool to room temperature;

[0066] S4. The quenched aluminum alloy is subjected to aging treatment at a temperature of 225℃ and a holding time of 10h.

[0067] S5. During cold rolling, the thickness reduction rate is controlled at 50%, the rolling passes are 3, and intermediate annealing is performed after each rolling pass. The annealing temperature is 300℃ and the holding time is 1h.

[0068] S6. The cold-rolled aluminum alloy is subjected to stretching treatment with a stretching deformation of 7.5% and a stretching speed of 27 mm / min.

[0069] S7. The stretched aluminum alloy is cold extruded, with the extrusion deformation set at 11% and the extrusion speed controlled at 12 mm / s.

[0070] Example 4:

[0071] S1. Determine the alloy composition according to the table below:

[0072] alloy Mg Zn Ti Li Cu Mn Al mass percentage / % 0.7％ 0.04％ 0.06％ 0.08％ 0.02％ 0.5％ the remaining

[0073] S2. A vacuum induction melting furnace was used for melting at a temperature of 730℃ for 3 hours, with an argon flow rate of 5 L / min and an argon pressure of 0.2 MPa. During the melting process, lithium content was periodically sampled and analyzed to ensure it remained within acceptable limits.

[0074] S3. Heat the aluminum alloy to the solution treatment temperature of 500℃, hold for 1 hour, and then rapidly cool to room temperature;

[0075] S4. The quenched aluminum alloy is subjected to aging treatment at a temperature of 225℃ and a holding time of 10h.

[0076] S5. During cold rolling, the thickness reduction rate is controlled at 45%, the rolling passes are 3, and intermediate annealing is performed after each rolling pass. The annealing temperature is 250℃ and the holding time is 1.5h.

[0077] S6. The cold-rolled aluminum alloy is subjected to stretching treatment with a stretching deformation of 5% and a stretching speed of 27 mm / min.

[0078] S7. The stretched aluminum alloy is cold extruded, with the extrusion deformation set at 6% and the extrusion speed controlled at 15mm / s.

[0079] Example 5:

[0080] S1. Determine the alloy composition according to the table below:

[0081] alloy Mg Zn Ti Li Cu Mn Al mass percentage / % 0.8％ 0.05％ 0.08％ 0.1％ 0.03％ 0.6％ the remaining

[0082] S2. A vacuum induction melting furnace was used for melting at a temperature of 700℃ for 4 hours, with an argon flow rate of 5 L / min and an argon pressure of 0.2 MPa. During the melting process, lithium content was periodically sampled and analyzed to ensure it remained within acceptable limits.

[0083] S3. Heat the aluminum alloy to the solution treatment temperature of 550°C, hold for 2 hours, and then rapidly cool to room temperature.

[0084] S4. The quenched aluminum alloy is subjected to aging treatment at a temperature of 150℃ and a holding time of 20h.

[0085] S5. During cold rolling, the thickness reduction rate is controlled at 60%, the rolling passes are 3, and intermediate annealing is performed after each rolling pass. The annealing temperature is 200℃ and the holding time is 2h.

[0086] S6. The cold-rolled aluminum alloy is subjected to stretching treatment with a stretching deformation of 5% and a stretching speed of 25 mm / min.

[0087] S7. The stretched aluminum alloy is cold extruded, with the extrusion deformation set at 10% and the extrusion speed controlled at 10mm / s.

[0088] As a further improvement, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a lightweight, high-strength aluminum alloy for power equipment, characterized in that, Includes the following steps: S1. Determine the alloy composition, including Al, Mg, Zn, Ti, Li, Cu, and Mn; carry out smelting using a vacuum induction melting furnace and argon gas protection; periodically sample and analyze the lithium content of the aluminum alloy during the smelting process and control it within the specified range. S2. Heat treatment: This includes the following sub-steps: S201 Solution treatment: Heat the aluminum alloy to the solution treatment temperature and hold it for a period of time; S202, Quenching: Rapidly cooling the aluminum alloy from the solution treatment temperature to room temperature; S203 is used to age quenched aluminum alloys to precipitate supersaturated solid solutions in the alloy. S3. Cold working: This includes the following sub-steps: S301, Cold rolling: Cold rolling of aged aluminum alloy, with the thickness reduction rate controlled between 40% and 60%; S302, Stretching: The cold-rolled aluminum alloy is stretched to plastically process the alloy, and the stretching deformation is 5-10%. S303, Cold extrusion: Cold extrusion of stretched aluminum alloy; The mass percentages of each element in S1 are: Mg 0.6-0.8%, Zn ≤0.05%, Ti ≤0.08%, Li ≤0.1%, Cu ≤0.03%, Mn 0.4-0.6%, and the remainder is Al.

2. The method for preparing a lightweight, high-strength aluminum alloy for power equipment according to claim 1, characterized in that, The melting temperature in S1 is 700–750℃, the melting time is 2–4h, the argon flow rate is 4–6L / min, and the argon pressure is 0.1–0.3MPa.

3. The method for preparing a lightweight, high-strength aluminum alloy for power equipment according to claim 1, characterized in that, The process parameters for the S201 solution treatment are: solution treatment temperature of 400–550℃ and solution treatment time of 0.5–2h.

4. The method for preparing a lightweight, high-strength aluminum alloy for power equipment according to claim 1, characterized in that, The aging treatment temperature in S203 is 150-250℃, and the aging holding time is 5-20h.

5. The method for preparing a lightweight, high-strength aluminum alloy for power equipment according to claim 1, characterized in that, In S301 cold rolling, the rolling passes are 3 times. After each rolling pass, intermediate annealing is performed. The annealing temperature is controlled at 200-300℃ and the holding time is 1-2 hours.

6. The method for preparing a lightweight, high-strength aluminum alloy for power equipment according to claim 1, characterized in that, The stretching speed of S302 is 25-50 mm / min.

7. The method for preparing a lightweight, high-strength aluminum alloy for power equipment according to claim 1, characterized in that, The extrusion deformation of S303 is set at 10% to 12%, and the extrusion speed is controlled at 10 to 15 mm / s.

8. The method for preparing a lightweight, high-strength aluminum alloy for power equipment according to claim 1, characterized in that, The vacuum degree of the vacuum induction melting furnace is 1-50 Pa.