6005A aluminum alloy for new energy automobile battery tray, preparation method and application

Abstract

The invention provides a 6005A aluminum alloy for a new energy automobile battery tray, a preparation method and application, and relates to the field of aluminum alloys for new energy automobile battery trays. The preparation method of the 6005A aluminum alloy for the new energy automobile battery tray comprises the following steps of smelting and casting, homogenizing treatment, extrusion quenching and aging. According to the 6005A aluminum alloy for the new energy automobile battery tray, the physical properties such as strength and plasticity of the aluminum alloy for the new energy automobile battery tray can be improved, and meanwhile the problem that the size deviation is large in the machining process of preparing the new energy automobile battery tray from the aluminum alloy is effectively avoided; the size stability of the aluminum alloy for the new energy automobile battery tray can be further improved, and then the production efficiency and safety of the aluminum alloy battery tray are improved.

Description

Technical Field

[0001] The present invention relates to the field of aluminum alloys for battery trays of new energy vehicles, and in particular to a 6005A aluminum alloy for battery trays of new energy vehicles, a preparation method and applications thereof. Background Art

[0002] Driven by current energy and environmental pressures, automobile technology in various countries is developing towards lightweight body, long driving range and low energy consumption. As one of the seven strategic industries in my country, new energy vehicles are of great significance to the development of the automobile industry.

[0003] As the world's energy crisis and environmental pollution become increasingly serious, electric vehicles will be the mainstream of future vehicles, and one of the important factors restricting its rapid development is the weight of the vehicle body. The lightweight of the vehicle body is closely related to reducing carbon dioxide emissions and saving energy, and it is also one of the important indicators affecting driving distance. Therefore, optimizing the body weight has become the top priority for the upgrading of new energy vehicles.

[0004] One of the main ways to reduce vehicle weight is to optimize the body material. Compared with traditional fuel vehicles, new energy electric vehicles have more core components of the three-electric system (battery, motor, and electronic control), which generally account for 30-40% of the weight of the new energy vehicle. The battery pack accounts for 18-30% of the weight of the vehicle, of which the battery tray accounts for about 10-20% of the weight of the battery pack, and there is a lot of room for lightweighting. At present, the main material used for the battery tray is high-strength steel. Although it has excellent processing and welding performance, it is heavy, has poor corrosion resistance, and is prone to chemical corrosion.

[0005] 6 series aluminum alloy (AI-Mg-Si) is a heat-treatable alloy that can achieve high strength and high corrosion resistance through heat treatment. At the same time, due to its low material density, under equal strength design, all-aluminum parts are about 40% lighter than steel parts, making it one of the best lightweight materials for new energy vehicles. Among them, 6005A is a typical 6 series medium-strength aluminum alloy with excellent extrudable and weldable properties. It can produce thin-walled aluminum profiles with complex cross-sections on extruders. Therefore, in recent years, more and more automobile manufacturers have studied its application in battery trays.

[0006] 6005A aluminum alloy, according to the requirements of the National Standard of the People's Republic of China GB / T 6892-2023 "General Industrial Aluminum and Aluminum Alloy Extruded Profiles", the room temperature mechanical properties of hollow profiles with grade 6005A, T6 state, and wall thickness ≤5.00mm must meet the following requirements: tensile strength ≥255MPa, specified non-proportional elongation strength ≥215Mpa, and elongation after fracture ≥6%. However, on the one hand, based on the requirements of new energy vehicles for both lightweight and safety, higher requirements are placed on the physical properties such as strength and plasticity of aluminum alloys used in battery trays for new energy vehicles; on the other hand, during the preparation of battery trays for new energy vehicles, the increase in the strength of aluminum alloys will lead to greater pressure on the extrusion die, which may easily lead to large dimensional deviations in the prepared new energy battery trays, and the poor dimensional stability of aluminum alloys, which is not conducive to subsequent processing; there is a contradictory relationship between the two, and the existing technology cannot effectively balance and optimize the two, and cannot improve the physical properties such as strength and plasticity of aluminum alloys used in battery trays for new energy vehicles while avoiding the problem of large dimensional deviations in the processing of preparing battery trays for new energy vehicles using aluminum alloys, thereby further improving the dimensional stability of aluminum alloys used in battery trays for new energy vehicles.

[0007] Therefore, it is of great significance to provide a 6005A aluminum alloy, preparation method and application for a new energy vehicle battery tray by comprehensively balancing all the factors affecting physical properties and dimensional stability in the preparation process of the new energy vehicle battery tray. Summary of the invention

[0008] In order to solve the technical problems existing in the prior art, the present invention provides a 6005A aluminum alloy for a new energy vehicle battery tray, a preparation method and an application thereof, which can effectively avoid the problem of large dimensional deviation in the processing of the new energy vehicle battery tray using the aluminum alloy while improving the physical properties such as strength and plasticity of the aluminum alloy for the new energy vehicle battery tray, and can further improve the dimensional stability of the aluminum alloy for the new energy vehicle battery tray, thereby improving the production efficiency and safety of the aluminum alloy battery tray.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: A method for preparing 6005A aluminum alloy for a new energy vehicle battery tray comprises the following steps: smelting and casting, homogenization treatment, extrusion quenching, and aging; The smelting and casting method comprises the following steps: feeding raw materials into a melting and casting furnace, heating and melting the raw materials to obtain a melt; introducing the melt into a static furnace, allowing the melt to stand, and then performing a first refining, a second refining, and casting to obtain an ingot. The ingot comprises the following components by mass percentage: Si 0.65-0.75wt%, Mg 0.55-0.65wt%, Fe 0.18-0.22wt%, Cu 0.2-0.25wt%, Mn 0.2-0.35wt%, Cr 0.1-0.25wt%, Zn0.01-0.05wt%, Ti 0.03-0.05wt%, and the balance is Al and unavoidable impurities; The average grain size of the ingot is 150-200 μm.

[0010] Preferably, in the smelting and casting, the heating and melting temperature is 720-750°C; The melt is introduced into a static furnace, and the temperature in the static furnace is controlled to be no less than 720°C.

[0011] Preferably, in the smelting and casting, the first refining temperature is 715-725°C; and the second refining temperature is 725-735°C.

[0012] Furthermore, the smelting and casting method is as follows: feeding the metal raw materials into a melting furnace, controlling the melting temperature to be 720-750°C, keeping the temperature and stirring to melt, and obtaining a melt; introducing the melt into a static furnace, controlling the temperature in the static furnace to be not less than 720°C, and after standing for 30 minutes, introducing nitrogen for the first refining and online degassing, controlling the hydrogen content in the melt to be ≤0.15mL / 100g, the first refining temperature to be 715-725°C, and after the first refining for 20-30 minutes, slagging; then performing a second refining and online degassing, controlling the second refining temperature to be 725-735°C, and after the second refining for 15-20 minutes, slagging; then standing for 20-30 minutes, using a 40-mesh plus a 60-mesh foam ceramic filter plate for online double-stage filtration, and then casting, controlling the casting speed to be 125-155mm / min, to obtain an ingot; Furthermore, the homogenization method is to homogenize the ingot, control the homogenization temperature to 565-575°C, and keep the homogenization time for not less than 10 hours; then cool to obtain the homogenized ingot.

[0013] Preferably, in the homogenization treatment, the final temperature of the controlled cooling after the homogenization treatment is: the external temperature of the ingot is ≤50°C, and the core temperature of the ingot is ≤150°C.

[0014] Furthermore, the extrusion quenching method is to control the temperature of the extrusion die to 450-500°C, control the temperature of the ingot after homogenization to 480-520°C, extrude the ingot after homogenization, and after the extrusion treatment, enter the quenching zone for quenching, control the temperature entering the quenching zone to be not less than 500°C, and the temperature out of the quenching zone to be not more than 50°C, so as to obtain a profile.

[0015] Preferably, in the extrusion quenching, the quenching adopts strong air cooling quenching, and the air cooling intensity adopts an unbalanced adjustment mode; the compressed air flow rate of the strong air cooling quenching is 3m 3 / min; During the strong air cooling quenching process, the upper left air cooling opening is controlled to 80%, the lower left air cooling flow opening is controlled to 80%, the upper right air cooling flow opening is controlled to 100%, and the lower right air cooling flow opening is controlled to 100%.

[0016] Preferably, in the extrusion process, the extrusion pressure is 180-230 MPa, the extrusion ratio is 20-60, and the extrusion rod advancement speed is 2-5 mm / s.

[0017] Furthermore, the aging method is to control the aging treatment temperature to 170-180° C. and the aging treatment time to 8 hours, and perform aging treatment on the profile after extrusion quenching to obtain a 6005A aluminum alloy profile for a new energy vehicle battery tray.

[0018] A 6005A aluminum alloy for a new energy vehicle battery tray is prepared by the aforementioned preparation method.

[0019] An application of the aforementioned 6005A aluminum alloy for new energy vehicle battery trays in the preparation of new energy vehicle battery trays.

[0020] Compared with the prior art, the present invention has the following beneficial effects: 1. The preparation method of 6005A aluminum alloy for new energy vehicle battery tray of the present invention comprehensively balances all factors affecting physical properties and dimensional stability in the preparation process of new energy vehicle battery tray, optimizes the composition ratio of 6005A aluminum alloy in a targeted manner, and specifically adjusts the element content in the original 6005A aluminum alloy formula. While increasing the Si and Mg contents, the Mn and Cr contents are controlled. While improving the strength, toughness and bending strength of 6005A aluminum alloy for new energy vehicle battery tray, the upper limit of quenching temperature is increased, recrystallization during solution treatment is inhibited, strengthening effect is improved, stress corrosion cracking sensitivity is reduced, overall alloy performance is improved, and grain size is adjusted.

[0021] 2. Furthermore, the preparation method of 6005A aluminum alloy for new energy vehicle battery tray of the present invention sets the relevant process parameters of homogenization treatment for the ingot of specific composition, and controls the temperature of the ingot after homogenization treatment; and after the homogenized ingot is extruded, the quenching intensity is adjusted, and failure treatment is carried out in conjunction with it. By comprehensively balancing all influencing factors from multiple aspects, it is possible to improve the physical properties such as strength and plasticity of the aluminum alloy for new energy vehicle battery tray, while effectively avoiding the problem of large dimensional deviation in the processing process of preparing new energy vehicle battery tray using aluminum alloy, and can further improve the dimensional stability of the aluminum alloy for new energy vehicle battery tray, thereby improving the production efficiency and safety of the aluminum alloy battery tray.

[0022] 3. The 6005A aluminum alloy used in the battery tray of new energy vehicles of the present invention has various mechanical properties far exceeding the existing national standards. The tensile strength of the 6005A aluminum alloy (wall thickness 2mm) used in the battery tray of new energy vehicles can reach 302MPa, the specified non-proportional elongation strength can reach 267MPa, and the elongation after fracture can reach 12.9%.

[0023] 4. The new energy vehicle battery tray of the present invention uses 6005A aluminum alloy, which is used in the preparation of new energy vehicle battery trays. The full-size deviation of the prepared battery tray is ±0.15mm. Compared with the existing production process using conventional 6005A, it can increase the qualified rate of finished products of new energy vehicle battery trays by 10%, effectively avoid the production of unqualified products, and reduce waste generation; at the same time, the prepared new energy vehicle battery tray is applied to the assembly, and the weight reduction effect exceeds 35%. DETAILED DESCRIPTION

[0024] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation methods of the present invention are now described.

[0025] Example 1 This embodiment provides a method for preparing 6005A aluminum alloy for a new energy vehicle battery tray, and the specific steps are as follows: (1) Melting and casting The metal raw materials are fed into a melting furnace, the melting temperature is controlled to be 725°C, and the melt is melted by stirring and keeping warm to obtain a melt; the melt is introduced into a static furnace, the temperature in the static furnace is controlled to be not less than 720°C, and after standing for 30 minutes, nitrogen is introduced for the first refining and online degassing, the hydrogen content in the melt is controlled to be ≤0.15mL / 100g, the first refining temperature is 715°C, and after the first refining for 20 minutes, slag is removed; then a second refining and online degassing are carried out, the second refining temperature is controlled to be 725°C, and after the second refining for 15 minutes, slag is removed; then standing for 20 minutes, online double-stage filtration is carried out using 40-mesh and 60-mesh foam ceramic filter plates, and then casting is carried out, the casting speed is controlled to be 125mm / min, and an ingot with an average grain size of 150μm is obtained.

[0026] The ingot includes the following components, by mass percentage: Si 0.68wt%, Mg 0.57wt%, Fe 0.22wt%, Cu 0.23wt%, Mn 0.26wt%, Cr 0.14wt%, Zn 0.01wt%, Ti 0.03wt%, and the balance is Al and inevitable impurities.

[0027] In the technical solution of this embodiment, all factors affecting physical properties and dimensional stability in the preparation process of the battery tray for new energy vehicles are comprehensively balanced, and the composition ratio of 6005A aluminum alloy is optimized in a targeted manner. Specifically, the element content in the original 6005A aluminum alloy formula is adjusted, and the Mn and Cr contents are controlled while increasing the Si and Mg contents. While improving the strength, toughness and bending strength of the 6005A aluminum alloy for the battery tray for new energy vehicles, the upper limit of the quenching temperature is increased, the recrystallization during the solution treatment process is inhibited, the strengthening effect is improved, the sensitivity to stress corrosion cracking is reduced, the overall performance of the alloy is improved, and the grain size is adjusted.

[0028] (2) Homogenization The ingot is homogenized, the homogenization temperature is controlled at 570°C, and the homogenization holding time is 10 hours; then it is cooled, and the final cooling temperature is controlled to be: the external temperature of the ingot is 50°C, the core temperature of the ingot is 140°C, and a homogenized ingot is obtained.

[0029] (3) Extrusion quenching The homogenized ingot is extruded, and after extrusion is completed, it enters the quenching zone for quenching to obtain a profile.

[0030] During the extrusion process, the temperature of the extrusion die is controlled to 480°C, the temperature of the ingot after homogenization is controlled to 500°C, the extrusion pressure is 220MPa, the extrusion ratio is 40, and the extrusion rod advancement speed is 3.5mm / s; after the extrusion is completed, the temperature entering the quenching zone is controlled to be 510°C, the temperature out of the quenching zone is 50°C, and the quenching method adopts strong air cooling quenching; the air cooling intensity adopts an unbalanced adjustment mode, and the compressed air flow rate of the air cooling quenching is 3m 3 / min, control the upper left air cooling opening to 80%, the lower left air cooling flow opening to 80%, the upper right air cooling flow opening to 100%, and the lower right air cooling flow opening to 100%.

[0031] (4) Time limit The aging treatment temperature was controlled to be 175°C and the aging treatment time was 8h. The profile after extrusion quenching was subjected to aging treatment to obtain a 6005A aluminum alloy profile for a new energy vehicle battery tray.

[0032] Furthermore, in the technical solution of this embodiment, for the ingot with a specific composition, the process parameters related to the homogenization treatment are set to control the temperature of the ingot after the homogenization treatment; and after the homogenized ingot is extruded, the quenching intensity is adjusted, and the failure treatment is coordinated. By comprehensively balancing all influencing factors from multiple aspects, it is possible to improve the physical properties such as strength and plasticity of the aluminum alloy used for the battery tray of new energy vehicles, while effectively avoiding the problem of large dimensional deviation in the processing of the battery tray of new energy vehicles using aluminum alloy, and further improve the dimensional stability of the aluminum alloy used for the battery tray of new energy vehicles, thereby improving the production efficiency and safety of the aluminum alloy battery tray.

[0033] This embodiment also provides a 6005A aluminum alloy for a new energy vehicle battery tray produced by the aforementioned production method.

[0034] This embodiment also provides an application of the aforementioned 6005A aluminum alloy for new energy vehicle battery trays in the preparation of new energy vehicle battery trays.

[0035] Example 2 This embodiment provides a method for preparing 6005A aluminum alloy for a new energy vehicle battery tray, and the specific steps are as follows: (1) Melting and casting The metal raw materials are fed into a melting furnace, the melting temperature is controlled to be 735°C, and the melt is melted by stirring and keeping warm to obtain a melt; the melt is introduced into a static furnace, the temperature in the static furnace is controlled to be not less than 720°C, and after standing for 30 minutes, nitrogen is introduced for the first refining and online degassing, the hydrogen content in the melt is controlled to be ≤0.15mL / 100g, the first refining temperature is 720°C, and after the first refining for 25 minutes, slag is removed; then a second refining and online degassing are carried out, the second refining temperature is controlled to be 730°C, and after the second refining for 20 minutes, slag is removed; then standing for 25 minutes, online double-stage filtration is carried out using 40-mesh and 60-mesh foam ceramic filter plates, and then casting is carried out, the casting speed is controlled to be 135mm / min, and an ingot with an average grain size of 180μm is obtained.

[0036] The ingot includes the following components, by mass percentage: Si 0.71wt%, Mg 0.58wt%, Fe 0.18wt%, Cu 0.2wt%, Mn 0.25wt%, Cr 0.16wt%, Zn 0.02wt%, Ti 0.05wt%, and the balance is Al and inevitable impurities.

[0037] In the technical solution of this embodiment, all factors affecting physical properties and dimensional stability in the preparation process of the battery tray for new energy vehicles are comprehensively balanced, and the composition ratio of 6005A aluminum alloy is optimized in a targeted manner. Specifically, the element content in the original 6005A aluminum alloy formula is adjusted, and the Mn and Cr contents are controlled while increasing the Si and Mg contents. While improving the strength, toughness and bending strength of the 6005A aluminum alloy for the battery tray for new energy vehicles, the upper limit of the quenching temperature is increased, the recrystallization during the solution treatment process is inhibited, the strengthening effect is improved, the sensitivity to stress corrosion cracking is reduced, the overall performance of the alloy is improved, and the grain size is adjusted.

[0038] (2) Homogenization The ingot is homogenized, the homogenization temperature is controlled at 575°C, and the homogenization holding time is 10 hours; then it is cooled, and the final cooling temperature is controlled to be: the external temperature of the ingot is 45°C, the core temperature of the ingot is 130°C, and a homogenized ingot is obtained.

[0039] (3) Extrusion quenching The homogenized ingot is extruded, and after extrusion is completed, it enters the quenching zone for quenching to obtain a profile.

[0040] During the extrusion process, the temperature of the extrusion die is controlled to 470°C, the temperature of the ingot after homogenization is controlled to 510°C, the extrusion pressure is 200MPa, the extrusion ratio is 35, and the extrusion rod advancement speed is 4mm / s; after the extrusion is completed, the temperature entering the quenching zone is controlled to be 515°C, the temperature out of the quenching zone is 45°C, and the quenching method adopts strong air cooling quenching; the air cooling intensity adopts an unbalanced adjustment mode, and the compressed air flow rate of the air cooling quenching is 3m 3 / min, control the upper left air cooling opening to 80%, the lower left air cooling flow opening to 80%, the upper right air cooling flow opening to 100%, and the lower right air cooling flow opening to 100%.

[0041] (4) Time limit The aging treatment temperature was controlled to be 180°C and the aging treatment time was 8h. The profile after extrusion quenching was subjected to aging treatment to obtain a 6005A aluminum alloy profile for a new energy vehicle battery tray.

[0042] Furthermore, in the technical solution of this embodiment, for the ingot with a specific composition, the process parameters related to the homogenization treatment are set to control the temperature of the ingot after the homogenization treatment; and after the homogenized ingot is extruded, the quenching intensity is adjusted, and the failure treatment is coordinated. By comprehensively balancing all influencing factors from multiple aspects, it is possible to improve the physical properties such as strength and plasticity of the aluminum alloy used for the battery tray of new energy vehicles, while effectively avoiding the problem of large dimensional deviation in the processing of the battery tray of new energy vehicles using aluminum alloy, and further improve the dimensional stability of the aluminum alloy used for the battery tray of new energy vehicles, thereby improving the production efficiency and safety of the aluminum alloy battery tray.

[0043] This embodiment also provides a 6005A aluminum alloy for a new energy vehicle battery tray produced by the aforementioned production method.

[0044] This embodiment also provides an application of the aforementioned 6005A aluminum alloy for new energy vehicle battery trays in the preparation of new energy vehicle battery trays.

[0045] Example 3 The present invention provides a method for preparing a 6005A aluminum alloy for a new energy vehicle battery tray, and the specific steps are as follows: (1) Melting and casting The metal raw materials are fed into a melting furnace, the melting temperature is controlled to be 725°C, and the melt is melted by stirring and keeping warm to obtain a melt; the melt is introduced into a static furnace, the temperature in the static furnace is controlled to be not less than 720°C, and after standing for 30 minutes, nitrogen is introduced for the first refining and online degassing, the hydrogen content in the melt is controlled to be ≤0.15mL / 100g, the first refining temperature is 725°C, and after the first refining for 30 minutes, slag is removed; then a second refining and online degassing are carried out, the second refining temperature is controlled to be 735°C, and after the second refining for 20 minutes, slag is removed; then standing for 30 minutes, online double-stage filtration is carried out using 40-mesh and 60-mesh foam ceramic filter plates, and then casting is carried out, the casting speed is controlled to be 140mm / min, and an ingot with an average grain size of 160μm is obtained.

[0046] The ingot includes the following components, by mass percentage: Si 0.71wt%, Mg 0.57wt%, Fe 0.19wt%, Cu 0.22wt%, Mn 0.24wt%, Cr 0.15wt%, Zn 0.02wt%, Ti 0.03wt%, and the balance is Al and inevitable impurities.

[0047] In the technical solution of this embodiment, all factors affecting physical properties and dimensional stability in the preparation process of the battery tray for new energy vehicles are comprehensively balanced, and the composition ratio of 6005A aluminum alloy is optimized in a targeted manner. Specifically, the element content in the original 6005A aluminum alloy formula is adjusted, and the Mn and Cr contents are controlled while increasing the Si and Mg contents. While improving the strength, toughness and bending strength of the 6005A aluminum alloy for the battery tray for new energy vehicles, the upper limit of the quenching temperature is increased, the recrystallization during the solution treatment process is inhibited, the strengthening effect is improved, the sensitivity to stress corrosion cracking is reduced, the overall performance of the alloy is improved, and the grain size is adjusted.

[0048] (2) Homogenization The ingot is homogenized, the homogenization temperature is controlled at 570°C, and the homogenization holding time is 10 hours; then it is cooled, and the final cooling temperature is controlled to be: the external temperature of the ingot is 50°C, the core temperature of the ingot is 140°C, and a homogenized ingot is obtained.

[0049] (3) Extrusion quenching The homogenized ingot is extruded, and after extrusion is completed, it enters the quenching zone for quenching to obtain a profile.

[0050] During the extrusion process, the temperature of the extrusion die is controlled to 475°C, the temperature of the ingot after homogenization is controlled to 515°C, the extrusion pressure is 205MPa, the extrusion ratio is 35, and the extrusion rod advancement speed is 4.2mm / s; after the extrusion is completed, the temperature entering the quenching zone is controlled to be 520°C, the temperature out of the quenching zone is 50°C, and the quenching method adopts strong air cooling quenching; the air cooling intensity adopts an unbalanced adjustment mode, and the compressed air flow rate of the air cooling quenching is 3m 3 / min, control the upper left air cooling opening to 80%, the lower left air cooling flow opening to 80%, the upper right air cooling flow opening to 100%, and the lower right air cooling flow opening to 100%.

[0051] (4) Time limit The aging treatment temperature was controlled to be 175°C and the aging treatment time was 8h. The profile after extrusion quenching was subjected to aging treatment to obtain a 6005A aluminum alloy profile for a new energy vehicle battery tray.

[0052] Furthermore, in the technical solution of this embodiment, for the ingot with a specific composition, the process parameters related to the homogenization treatment are set to control the temperature of the ingot after the homogenization treatment; and after the homogenized ingot is extruded, the quenching intensity is adjusted, and the failure treatment is coordinated. By comprehensively balancing all influencing factors from multiple aspects, it is possible to improve the physical properties such as strength and plasticity of the aluminum alloy used for the battery tray of new energy vehicles, while effectively avoiding the problem of large dimensional deviation in the processing of the battery tray of new energy vehicles using aluminum alloy, and further improve the dimensional stability of the aluminum alloy used for the battery tray of new energy vehicles, thereby improving the production efficiency and safety of the aluminum alloy battery tray.

[0053] This embodiment also provides a 6005A aluminum alloy for a new energy vehicle battery tray produced by the aforementioned production method.

[0054] This embodiment also provides an application of the aforementioned 6005A aluminum alloy for new energy vehicle battery trays in the preparation of new energy vehicle battery trays.

[0055] The tensile strength, yield strength and elongation of the 6005A aluminum alloy (wall thickness 2 mm) for the new energy vehicle battery tray of Examples 1-3 were tested respectively; at the same time, the 6005A aluminum alloy (grade 6005A, state T6, wall thickness 2 mm) in the national standard GB / T 6892-2023 "General Industrial Aluminum and Aluminum Alloy Extrusion Profiles" was set as Comparative Example 1, and its tensile strength, yield strength and elongation were tested; the test results are shown in the following table:

[0056] It can be seen that the relevant properties of the 6005A aluminum alloy for the new energy vehicle battery tray of Examples 1-3 of the present invention are far greater than the relevant requirements of the national standard GB / T 6892-2023 "General Industrial Aluminum and Aluminum Alloy Extrusion Profiles". The room temperature mechanical properties of Examples 1-3 (T6 state, hollow profile with a wall thickness of 2.00 mm): tensile strength ≥ 290 MPa, specified non-proportional elongation strength ≥ 250 MPa, and elongation after fracture ≥ 10%.

[0057] Furthermore, a new energy vehicle battery tray is prepared using 6005A aluminum alloy using the new energy vehicle battery tray of Example 3. After testing, the full-size deviation of the prepared new energy vehicle battery tray is ±0.15mm. Compared with the prior art, the finished product qualification rate of the new energy vehicle battery tray can be increased by 10%, effectively avoiding the production of unqualified products and reducing waste generation.

[0058] Unless otherwise specified, all percentages used in the present invention are by mass.

[0059] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing 6005A aluminum alloy for new energy vehicle battery tray, characterized in that: The process includes the following steps: smelting and casting, homogenization, extrusion quenching, and aging; The smelting and casting method comprises the following steps: feeding raw materials into a melting and casting furnace, heating and melting the raw materials to obtain a melt; introducing the melt into a static furnace, allowing the melt to stand, and then performing a first refining, a second refining, and casting to obtain an ingot. The ingot comprises the following components by mass percentage: Si 0.65-0.75wt%, Mg 0.55-0.65wt%, Fe0.18-0.22wt%, Cu 0.2-0.25wt%, Mn 0.2-0.35wt%, Cr 0.1-0.25wt%, Zn 0.01-0.05wt%, Ti0.03-0.05wt%, and the balance is Al and inevitable impurities; The average grain size of the ingot is 150-200 μm.

2. The method for preparing 6005A aluminum alloy for new energy vehicle battery tray according to claim 1, characterized in that: During the smelting and casting, the melting temperature is 720-750°C; The melt is introduced into a static furnace, and the temperature in the static furnace is controlled to be no less than 720°C.

3. The method for preparing 6005A aluminum alloy for new energy vehicle battery tray according to claim 1, characterized in that: In the smelting and casting, the first refining temperature is 715-725°C; the second refining temperature is 725-735°C.

4. The method for preparing 6005A aluminum alloy for new energy vehicle battery tray according to claim 1, characterized in that: The homogenization method comprises the following steps: homogenizing the ingot, controlling the homogenization temperature to be 565-575° C., and keeping the homogenization temperature for no less than 10 hours; and then cooling the ingot to obtain the homogenized ingot.

5. The method for preparing 6005A aluminum alloy for new energy vehicle battery tray according to claim 4, characterized in that: In the homogenization treatment, the final temperature of the controlled cooling after the homogenization treatment is: the external temperature of the ingot is ≤50°C, and the core temperature of the ingot is ≤150°C.

6. The method for preparing 6005A aluminum alloy for new energy vehicle battery tray according to claim 1, characterized in that: The extrusion quenching method comprises the following steps: controlling the temperature of the extrusion die to 450-500° C., controlling the temperature of the homogenized ingot to 480-520° C., extruding the homogenized ingot, and quenching the ingot in a quenching zone after the extrusion, controlling the temperature in the quenching zone to be no less than 500° C., and controlling the temperature out of the quenching zone to be no more than 50° C., thereby obtaining a profile.

7. The method for preparing 6005A aluminum alloy for new energy vehicle battery tray according to claim 6, characterized in that: In the extrusion quenching, the quenching is carried out by strong air cooling quenching, and the compressed air flow rate of the strong air cooling quenching is 3m 3 / min; During the strong air cooling quenching process, the upper left air cooling opening is controlled to 80%, the lower left air cooling flow opening is controlled to 80%, the upper right air cooling flow opening is controlled to 100%, and the lower right air cooling flow opening is controlled to 100%.

8. The method for preparing 6005A aluminum alloy for new energy vehicle battery tray according to claim 1, characterized in that: The aging method is to control the aging treatment temperature to 170-180° C. and the aging treatment time to 8 hours, perform aging treatment on the profile after extrusion quenching, and prepare a 6005A aluminum alloy profile for a new energy vehicle battery tray.

9. A 6005A aluminum alloy for a new energy vehicle battery tray, characterized in that: The method is prepared by the method according to any one of claims 1 to 8.

10. An application of 6005A aluminum alloy for a new energy vehicle battery tray as claimed in claim 9, characterized in that: Application in the preparation of battery trays for new energy vehicles.

Images