A method of producing a 6082 aluminium alloy

Abstract

The application discloses a preparation method of 6082 aluminum alloy; the method comprises the following steps: S1, melting the easy-open can waste aluminum into aluminum liquid, then adding aluminum ingot, Al-10Mn intermediate alloy, Al-12Si intermediate alloy and magnesium ingot, and obtaining melt I after stirring and slagging; S2, mixing the melt I, a refining agent and a modifier to perform refining and modification treatment, and obtaining melt II after stirring and slagging; S3, sequentially performing filtering, casting, homogenization treatment, deformation, solid solution treatment and aging heat treatment on the melt II, and obtaining the 6082 aluminum alloy; the 6082 aluminum alloy prepared by the preparation method has the advantages that the easy-open can waste material is regenerated and utilized, and the mechanical properties of the aluminum alloy material prepared by using primary aluminum as raw material are equivalent.

Description

Technical Field

[0001] This invention relates to the field of aluminum processing technology, and in particular to a method for preparing 6082 aluminum alloy. Background Technology

[0002] 6082 aluminum alloy belongs to the Al-Mg-Si system and is a heat-treatable strengthening alloy. It possesses excellent comprehensive properties and has broad application prospects in the automotive, machinery, electronics, power, rail transportation, and equipment manufacturing industries. Currently, 6082 aluminum alloy is typically produced by smelting primary aluminum, casting it, rolling it into sheets or extruding it into profiles, and then further improving its strength through solution treatment and artificial aging. While this traditional processing method is a mature technology, it suffers from high raw material costs. Using recycled aluminum as raw material can significantly reduce production costs. However, producing high-performance aluminum alloys from recycled aluminum is technically challenging.

[0003] Currently, based on the low-carbon goals of energy conservation, emission reduction, and green development, both domestic and international efforts are focused on developing waste aluminum recycling technologies to achieve the preservation or added value of waste aluminum through recycling. Among these, aluminum cans are a major type of recycled aluminum raw material with enormous development potential. Aluminum cans are typically made of two or three aluminum alloys. The can body is generally made of Al-Mn 3104 aluminum alloy, the can lid is generally made of Al-Mg 5182 aluminum alloy, and the pull tab is generally made of 5182 aluminum alloy or Al-Cu-Mg (7 series) alloy. Aluminum cans are disposable consumer products. Recycled cans are usually not separated from the lid; they are directly pressed together and subsequently melted down after paint removal to form used beverage cans (UBC). Although these used beverage cans have lower costs, their complex composition and high impurity content make them difficult to smelt into high-end aluminum alloy materials. They are usually downgraded and used as raw materials for mid- to low-end aluminum alloy products.

[0004] However, there are currently no reports on the preparation of 6082 aluminum alloy using recycled aluminum ingots from aluminum cans as the main raw material. 6082 aluminum alloy belongs to the Al-Mg-Si alloy system, and its composition differs significantly from that of recycled aluminum ingots from aluminum cans. After smelting and casting, 6082 aluminum alloy typically needs to be rolled into sheet or strip, or extruded into profiles, requiring excellent ductility and high strength. However, it is difficult to achieve these strength and toughness targets when smelting using recycled aluminum as the main raw material.

[0005] Therefore, there is an urgent need to develop a high-performance 6082 aluminum alloy based on scrap aluminum from beverage cans as the main raw material. Summary of the Invention

[0006] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, the first aspect of this invention proposes a method for preparing 6082 aluminum alloy. This 6082 aluminum alloy can use scrap aluminum from beverage cans as the main raw material and has mechanical properties comparable to aluminum alloys prepared from primary aluminum.

[0007] According to a first aspect of the present invention, a method for preparing 6082 aluminum alloy is provided, comprising the following steps: S1. First, melt the aluminum composite ingots from the aluminum cans into molten aluminum, then add aluminum ingots, Al-10Mn master alloy, Al-12Si master alloy and magnesium ingots, stir and remove slag to obtain melt I; S2. Melt I, refining agent and modifier are mixed and refined and modified. After stirring and slag removal, melt II is obtained. S3. The melt II is sequentially filtered, cast, homogenized, deformed, solution treated and aged heat treated to obtain 6082 aluminum alloy. Relative to 100 parts by weight of the aluminum ingot from the recycled aluminum can, the aluminum ingot contains 80-85 parts by weight; the Al-10Mn master alloy contains 3.8-4.2 parts by weight; the Al-12Si master alloy contains 9.5-11.5 parts by weight; and the magnesium ingot contains 1.2-1.4 parts by weight. The refining agent comprises KCl, MgCl2, NaF, CaF2 and Na3AlF6; The modifier comprises an Al-3Ti aluminum alloy containing 15-25 wt.% TiB2 particles.

[0008] According to a preferred embodiment of the present invention, the refining agent comprises the following components in mass percentage: KCl: 30~40%; MgCl2: 20~30%; NaF: 5~10%; CaF2: 5~15%; Na3AlF6: 25~35%; the sum of the contents of all components is 100%.

[0009] According to a preferred embodiment of the present invention, the refining agent comprises the following components in mass percentage: KCl: 30%; MgCl2: 30%; NaF: 5%; CaF2: 5~15%; Na3AlF6: 25~35%; the sum of the contents of all components is 100%.

[0010] According to a preferred embodiment of the present invention, the refining agent accounts for 1.5 to 3.0% of the total mass of the aluminum composite ingot from the beverage can, aluminum ingot, Al-10Mn master alloy, Al-12Si master alloy and magnesium ingot.

[0011] According to a preferred embodiment of the present invention, the modifier accounts for 1.5 to 2.5% of the total mass of the aluminum composite ingot from the beverage can, aluminum ingot, Al-10Mn master alloy, Al-12Si master alloy and magnesium ingot.

[0012] According to a preferred embodiment of the present invention, the aluminum ingot is industrially recycled aluminum with an Al content ≥ 99.7 wt.%.

[0013] According to a preferred embodiment of the present invention, the magnesium ingot contains Mg ≥ 99.95 wt.%.

[0014] According to a preferred embodiment of the present invention, the aluminum composite ingot made from waste aluminum cans refers to a composite ingot formed by directly pressing waste aluminum cans into a single piece and then melting them together after paint removal.

[0015] According to a preferred embodiment of the present invention, in step S1, the melting temperature is 710~750°C.

[0016] According to a preferred embodiment of the present invention, the temperature of the aging heat treatment is 150~200℃.

[0017] According to a preferred embodiment of the present invention, the aging heat treatment time is 6 to 10 hours.

[0018] According to a preferred embodiment of the present invention, the solution treatment temperature is 520°C to 540°C.

[0019] According to a preferred embodiment of the present invention, the solution treatment time is 1 to 3 hours.

[0020] According to a preferred embodiment of the invention, the deformation includes rolling and / or extrusion.

[0021] According to a preferred embodiment of the present invention, the rolling process includes hot rolling and cold rolling.

[0022] The method for preparing 6082 aluminum alloy according to embodiments of the present invention has at least the following beneficial effects: This invention uses aluminum composite ingots from recycled aluminum cans as the main raw material, adds specific refining agents and modifiers, and combines them with specific amounts of aluminum ingots, Al-10Mn master alloy, Al-12Si master alloy, and magnesium ingots to prepare 6082 aluminum alloy. This not only realizes the value-added recycling of aluminum can waste, but also achieves mechanical properties comparable to those of aluminum alloy materials prepared from primary aluminum.

[0023] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Detailed Implementation

[0024] The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described in conjunction with the embodiments, but the present invention is not limited to these embodiments.

[0025] Unless otherwise specified, the reagents, methods and equipment used in this invention are all conventional reagents, methods and equipment in this technical field.

[0026] In some embodiments of the present invention, a method for preparing 6082 aluminum alloy is provided, comprising the following steps: S1. First, melt the aluminum composite ingots from the aluminum cans into molten aluminum, then add aluminum ingots, Al-10Mn master alloy, Al-12Si master alloy and magnesium ingots, stir and remove slag to obtain melt I; S2. Melt I, refining agent and modifier are mixed and refined and modified. After stirring and slag removal, melt II is obtained. S3. The melt II is sequentially filtered, cast, homogenized, deformed, solution treated and aged heat treated to obtain 6082 aluminum alloy. Relative to 100 parts by weight of the aluminum ingot from the recycled aluminum can, the aluminum ingot contains 80-85 parts by weight; the Al-10Mn master alloy contains 3.8-4.2 parts by weight; the Al-12Si master alloy contains 9.5-11.5 parts by weight; and the magnesium ingot contains 1.2-1.4 parts by weight. The refining agent comprises KCl, MgCl2, NaF, CaF2 and Na3AlF6; The modifier comprises an Al-3Ti aluminum alloy containing 15-25 wt.% TiB2 particles.

[0027] In some embodiments of the present invention, the refining agent comprises the following components by mass percentage: KCl: 30~40%; MgCl2: 20~30%; NaF: 5~10%; CaF2: 5~15%; Na3AlF6: 25~35%; the sum of the contents of all components is 100%.

[0028] In some embodiments of the present invention, the refining agent comprises the following components by mass percentage: KCl: 35%; MgCl2: 25%; NaF: 5%; CaF2: 5~15%; Na3AlF6: 25~35%; the sum of the contents of all components is 100%.

[0029] In some embodiments of the present invention, the refining agent accounts for 1.5 to 3.0% of the total mass of the aluminum composite ingot from the beverage can, aluminum ingot, Al-10Mn master alloy, Al-12Si master alloy and magnesium ingot.

[0030] In some embodiments of the present invention, the modifier accounts for 1.5 to 2.5% of the total mass of the aluminum composite ingot from the beverage can, aluminum ingot, Al-10Mn master alloy, Al-12Si master alloy and magnesium ingot.

[0031] In some embodiments of the present invention, the aluminum ingot is industrially recycled aluminum with an Al content ≥ 99.7 wt.%.

[0032] In some embodiments of the present invention, the magnesium ingot contains Mg ≥ 99.95 wt.%.

[0033] In some embodiments of the present invention, the aluminum composite ingot from aluminum cans refers to the ingot that is directly pressed into a single piece and then melted together after paint removal.

[0034] In some embodiments of the present invention, in step S1, the melting temperature is 710~750°C. For example, it includes 710°C, 715°C, 720°C, 725°C, 730°C, 735°C, 740°C, 745°C, 750°C, or any sub-range composed of any two of the above values.

[0035] In some embodiments of the present invention, the temperature of the aging heat treatment is 150~200°C. For example, it includes 150°C, 160°C, 170°C, 175°C, 180°C, 190°C, 200°C, or any sub-range composed of any two of the above values.

[0036] In some embodiments of the present invention, the aging heat treatment time is 6 to 10 hours. For example, it includes 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, or any sub-range consisting of two of the above values.

[0037] In some embodiments of the present invention, the solution treatment temperature is 520°C to 540°C. For example, it includes 520°C, 525°C, 530°C, 535°C, 540°C, or any sub-range consisting of any two of the above values.

[0038] In some embodiments of the present invention, the solution treatment time is 1 to 3 hours.

[0039] In some embodiments of the invention, the deformation includes rolling and / or extrusion.

[0040] In some embodiments of the present invention, the rolling process includes hot rolling and cold rolling.

[0041] Understandably, this invention, which uses recycled aluminum cans to prepare 6082 aluminum alloy material, faces two main challenges: 1) Significant compositional differences. 6082 aluminum alloy is an Al-Mg-Si alloy, while recycled aluminum can ingots (UBC) are mainly composed of Al-Mn and Al-Mg alloys. 2) High impurity content. Both the inner and outer surfaces of aluminum cans are coated, therefore, high-temperature paint removal is usually required before melting, resulting in a thickened oxide layer on the surface. Furthermore, recycled aluminum cans often contain various dissimilar metal impurities such as iron, copper, and zinc, leading to a high impurity content in the UBC and making it difficult to formulate high-end alloys.

[0042] To address the challenge of significant compositional differences, this invention fully considers the burn-off rates of various elements. Through meticulous calculations and repeated experiments, a 6082 aluminum alloy was successfully formulated using recycled aluminum can ingots (UBC), pure aluminum, pure magnesium, Al-Mn master alloy, and Al-Si master alloy as raw materials. The consumed recycled aluminum cans comprise 50% of the alloy by mass, and the total mass fraction of consumed recycled aluminum is close to 85%. Compared to using primary aluminum to formulate the 6082 aluminum alloy, this invention saves approximately 40% in material costs and significantly reduces energy consumption and carbon emissions.

[0043] To address the aforementioned challenge of high impurity content, this invention, through numerous experiments, successfully formulated a special refining agent containing fluoride salts (KCl+MgCl2+NaF+CaF2+Na3AlF6). This agent comprehensively utilizes the dissolving effect of cryolite Na3AlF6 on the alumina film, the adsorption effect of chloride salts, and the displacement effect of fluoride salts to fully degas and remove slag from the aluminum melt, while controlling the content of each element within the standard allowable range. This invention also employs a special modifier (Al-3Ti aluminum alloy containing TiB2 particles) to replace the conventionally used Al-Ti-B modifier. This releases more crystallization nuclei in the melt, resulting in a more uniform and finer grain structure within the ingot during alloy solidification, thereby producing high-quality 6082 aluminum alloy ingots.

[0044] In summary, this invention uses aluminum composite ingots from recycled aluminum cans as the main raw material, adds specific refining agents and modifiers, and combines them with specific amounts of aluminum ingots, Al-10Mn master alloy, Al-12Si master alloy, and magnesium ingots to prepare 6082 aluminum alloy. This not only realizes the value-added recycling of aluminum can waste, but also achieves mechanical properties comparable to those of aluminum alloy materials prepared from primary aluminum.

[0045] Some of the raw materials used in the embodiments and comparative examples of this invention are as follows: Aluminum composite ingots from aluminum can waste: purchased from Zhongliming Company; Aluminum ingots: recycled industrial pure aluminum, Al content ≥ 99.7 wt.%; purchased from Zhongliming Company; Al-10Mn master alloy, Al-12Si master alloy, magnesium ingots: commercially available; Refining agent A: Prepared according to the following mass ratio: KCl:MgCl2:NaF:CaF2:Na3AlF6 = 30%:30%:5%:5%:30%; commercially available.

[0046] Conventional refining agent B: (45% KCl + 35% NaCl + 20% MgCl2); commercially available.

[0047] Refining agent C: Porous granular refining agent containing SiO2 (its component mass fraction ratio is: KCl:MgCl2:CaF2:Na3AlF6:SiO2=45%:40%:5%:5%:5%); purchased from Zhangjiagang Yuxin Metallurgical Materials Co., Ltd. Modifier A: Al-3Ti aluminum alloy block containing 20 wt.% TiB2 particles; purchased from Foshan Yongchuang Intelligent Technology Co., Ltd. Conventional modifier B: Al-5Ti-B aluminum alloy rod material; Example 1 This example provides a method for preparing 6082 aluminum alloy (bar), the steps of which are as follows: Step 1: Melt 1000 kg of recycled aluminum can ingot (UBC) into molten aluminum at a high temperature of 710~750℃. Then, add 850 kg of recycled industrial pure aluminum, 40 kg of Al-Mn master alloy, 100 kg of Al-Si master alloy, and 12.5 kg of pure magnesium to the melt ingot in sequence. After thorough stirring and slag removal, let it stand for 10 minutes.

[0048] Step 2: Add refining agent A and modifier A to the melt obtained in Step 1 to perform deep refining and modification treatment on the melt. The amount added is about 2% of the melt mass. After thorough stirring and slag removal, let it stand for 25 minutes.

[0049] Step 3: The refined melt is filtered using conventional methods and cast into Φ100mm round ingots. Then, it is homogenized at 565℃ for 24 hours and hot extruded into Φ20mm round bars (extrusion ingot heating temperature 460℃, extrusion ratio 30.25, extrusion speed 15m / min). After extrusion, it is directly water-quenched online.

[0050] Step 4: The round bar prepared in Step 3 is subjected to artificial aging heat treatment at 175 ℃ for 8 h to finally obtain 6082 aluminum alloy material.

[0051] Example 2 This example provides a method for preparing 6082 aluminum alloy (profiles), the steps of which are as follows: Step 1: Melt 1000 kg of recycled aluminum can ingot (UBC) into molten aluminum at a high temperature of 710~750 ℃. Then, add 850 kg of recycled industrial pure aluminum, 40 kg of Al-Mn master alloy, 100 kg of Al-Si master alloy, and 12.5 kg of pure magnesium to the molten ingot in sequence. After thorough stirring and slag removal, let it stand for 10 minutes.

[0052] Step 2: Add a refining agent A and a modifier A to the melt obtained in Step 1 to perform deep refining and modification treatment on the melt. The amount added is about 2% of the melt mass. After thorough stirring and slag removal, let it stand for 30 minutes.

[0053] Step 3: The refined melt is filtered using conventional methods and cast into Φ220mm round ingots. Then, it is homogenized at 565℃ for 24 hours and hot extruded into solid profiles with a minimum wall thickness of 1.5mm (extrusion ingot heating temperature 460℃, extrusion ratio 35, extrusion speed 13.5m / min). After extrusion, it is directly water-quenched online.

[0054] Step 4: The profile prepared in Step 3 is subjected to artificial aging heat treatment at 175 ℃ for 8 h to finally obtain 6082 aluminum alloy profile with excellent comprehensive performance.

[0055] Example 3 This example provides a method for preparing 6082 aluminum alloy (strip), the steps of which are as follows: Step 1: Melt 1000 kg of recycled aluminum can ingot (UBC) into molten aluminum at a high temperature of 710~750 ℃. Then, add 850 kg of recycled industrial pure aluminum, 40 kg of Al-Mn master alloy, 100 kg of Al-Si master alloy, and 12.5 kg of pure magnesium to the molten ingot in sequence. After thorough stirring and slag removal, let it stand for 10 minutes.

[0056] Step 2: Add a special refining agent A and a modifier A to the melt obtained in Step 1 to deeply refine and modify the melt. The amount added is about 2% of the melt mass. After thorough stirring and slag removal, let it stand for 25 minutes.

[0057] Step 3: The refined melt is filtered using conventional methods and cast into flat ingots of 120mm×850mm×1500mm. Then, it undergoes homogenization treatment at 565℃ for 24 hours and hot rolling to a thickness of 10mm to form a slab (slab heating temperature 465℃, final rolling temperature not lower than 375℃, deformation rate per pass 10~30%). Finally, it is cold rolled and intermediate annealed (400℃×2h) to form a sheet or strip with a thickness of 2mm.

[0058] Step 4: The 2mm sheet and strip prepared in Step 3 are subjected to solution treatment at 525℃ for 3 hours and artificial aging heat treatment at 175℃ for 8 hours to finally obtain 6082 aluminum alloy material.

[0059] Comparative Example 1 This example provides a method for preparing 6082 aluminum alloy (bar), the steps of which are as follows: Step 1: Melt 1000 kg of recycled aluminum can ingot (UBC) into molten aluminum at a high temperature of 710~750 ℃. Then, add 850 kg of recycled industrial pure aluminum, 40 kg of Al-Mn master alloy, 100 kg of Al-Si master alloy, and 12.5 kg of pure magnesium to the molten ingot in sequence. After thorough stirring and slag removal, let it stand for 10 minutes.

[0060] Step 2: Add 2% by mass of conventional refining agent (KCl+NaCl+MgCl2) and conventional Al-5Ti-1B refining agent to the melt obtained in Step 1 to refine and modify the melt; after thorough stirring and slag removal, let it stand for 30 minutes.

[0061] Step 3: The refined melt is modified and filtered using conventional methods, and then cast into Φ100mm round ingots. After homogenization treatment at 565℃ for 24 hours, it is hot extruded into Φ20mm round bars (extrusion ingot heating temperature 460℃, extrusion ratio 30.25, extrusion speed 15m / min). After extrusion, it is directly water-cooled and quenched online.

[0062] Step 4: The round bar prepared in Step 3 is subjected to artificial aging heat treatment at 175 ℃ for 8 h to finally obtain the finished 6082 aluminum alloy bar.

[0063] Comparative Example 2 This example provides a method for preparing 6082 aluminum alloy (bar), the steps of which are as follows: Step 1: After high-temperature paint removal treatment, 1000 kg of recycled aluminum scrap from aluminum cans is directly immersed in molten aluminum at a high temperature of 710~750℃ for melting. Then, 850 kg of recycled industrial pure aluminum, 40 kg of Al-Mn master alloy, 100 kg of Al-Si master alloy, and 12.5 kg of pure magnesium are added to the melt in sequence. After thorough stirring and slag removal, the mixture is allowed to stand for 10 minutes.

[0064] Step 2: Add refining agent A and modifier A to the melt obtained in Step 1 to perform deep refining and modification treatment on the melt. The amount added is about 2% of the melt mass. After thorough stirring and slag removal, let it stand for 30 minutes.

[0065] Step 3: The refined melt is modified and filtered using conventional methods, and then cast into Φ100mm round ingots. After homogenization treatment at 565℃ for 24 hours, it is hot extruded into Φ20mm round bars (extrusion ingot heating temperature 460℃, extrusion ratio 30.25, extrusion speed 15m / min). After extrusion, it is directly water-cooled and quenched online.

[0066] Step 4: The round bar prepared in Step 3 is subjected to artificial aging heat treatment at 175 ℃ for 8 h to finally obtain the finished 6082 aluminum alloy bar.

[0067] Comparative Example 3 This example provides a 6082 aluminum alloy (profile), the component amounts are shown in Table 1, and the preparation method is as follows: Step 1: Melt 1000 kg of recycled aluminum can ingot (UBC) into molten aluminum at a high temperature of 710~750 ℃. Then, add 850 kg of recycled industrial pure aluminum, 40 kg of Al-Mn master alloy, 100 kg of Al-Si master alloy, and 12.5 kg of pure magnesium to the molten ingot in sequence. After thorough stirring and slag removal, let it stand for 10 minutes.

[0068] Step 2: Add conventional refining agent B (KCl+NaCl+MgCl2) to the melt obtained in Step 1 to refine the melt, and use a modifier A to modify the melt. The amount added is about 2% of the melt mass. After thorough stirring and slag removal, let it stand for 30 minutes.

[0069] Step 3: The refined melt is filtered using conventional methods and cast into Φ220mm round ingots. It is then processed into solid extruded profiles using the same process as in Example 2.

[0070] Step 4: Perform heat treatment on the extruded profile using the same process as in Example 2.

[0071] Comparative Example 4 This example provides a 6082 aluminum alloy (profile), the component amounts are shown in Table 1, and the preparation method is as follows: Step 1: Melt 1000 kg of recycled aluminum can ingot (UBC) into molten aluminum at a high temperature of 710~750 ℃. Then, add 850 kg of recycled industrial pure aluminum, 40 kg of Al-Mn master alloy, 100 kg of Al-Si master alloy, and 12.5 kg of pure magnesium to the molten ingot in sequence. After thorough stirring and slag removal, let it stand for 10 minutes.

[0072] Step 2: Add refining agent A and conventional modifier B (Al-5Ti-B aluminum alloy rod) to the melt obtained in Step 1 to perform deep refining and modification treatment on the melt. The amount added is about 2% of the melt mass. After thorough stirring and slag removal, let it stand for 30 minutes.

[0073] Step 3: The refined melt is filtered using conventional methods and cast into Φ220mm round ingots. Then, it is homogenized at 565℃ for 24 hours and hot extruded into solid profiles with a minimum wall thickness of 1.5mm (extrusion ingot heating temperature 460℃, extrusion ratio 35, extrusion speed 13.5m / min). After extrusion, it is directly water-quenched online.

[0074] Step 4: The profile prepared in Step 3 is subjected to artificial aging heat treatment at 175 ℃ for 8 h to finally obtain 6082 aluminum alloy profile with excellent comprehensive performance.

[0075] Comparative Example 5 This example provides a 6082 aluminum alloy (profile), the component amounts are shown in Table 1, and the preparation method is as follows: Step 1: Melt 1000 kg of recycled aluminum can ingot (UBC) into molten aluminum at a high temperature of 710~750 ℃. Then, add 850 kg of recycled industrial pure aluminum, 40 kg of Al-Mn master alloy, 100 kg of Al-Si master alloy, and 12.5 kg of pure magnesium to the molten ingot in sequence. After thorough stirring and slag removal, let it stand for 10 minutes.

[0076] Step 2: Add refining agent C and modifier A to the melt obtained in Step 1 to perform deep refining and modification treatment on the melt. The amount added is about 2% of the melt mass. After thorough stirring and slag removal, let it stand for 30 minutes.

[0077] Step 3: The refined melt is filtered using conventional methods and cast into Φ220mm round ingots. Then, it is homogenized at 565℃ for 24 hours and hot extruded into solid profiles with a minimum wall thickness of 1.5mm (extrusion ingot heating temperature 460℃, extrusion ratio 35, extrusion speed 13.5m / min). After extrusion, it is directly water-quenched online.

[0078] Step 4: The profile prepared in Step 3 is subjected to artificial aging heat treatment at 175 ℃ for 8 h to finally obtain 6082 aluminum alloy profile with excellent comprehensive performance.

[0079] Component analysis and performance testing The chemical composition of the 6082 aluminum alloy prepared in the embodiments of the present invention was determined by the method specified in standard GB / T 20975.25-2020. The results are shown in Table 1.

[0080] Table 1

[0081] The 6082 aluminum alloys prepared in the embodiments and comparative examples of this invention were subjected to routine room temperature mechanical property tests on various samples using the methods specified in standard GB / T228.1-2021. The results are shown in Table 2.

[0082] Table 2

[0083] As can be seen from the test results in Table 2, the raw materials and process methods of the present invention used in Examples 1 to 3, with UBC (unrefined aluminum can ingot) as the main raw material, resulted in 6082 aluminum alloy bars, profiles and plates that all have excellent comprehensive mechanical properties, comparable to the performance of corresponding 6082 aluminum alloy products made with primary aluminum.

[0084] Comparative Example 1 used conventional refining agents and modifiers during smelting, but did not employ the special refining agents and modifiers of this invention to treat the aluminum melt. Therefore, it failed to achieve sufficient refining and effective modification treatment of the recycled 6082 aluminum melt, resulting in a higher internal impurity content, coarser grains, and reduced mechanical properties, especially the plasticity index (A). gt () decreased significantly.

[0085] Comparative Example 2 used bulk aluminum cans instead of composite ingots (UBC) to formulate 6082 aluminum alloy. Although the special refining agent and modifier of this invention were subsequently used to treat the aluminum melt, it still failed to fully remove inclusions and impurities from the alloy, resulting in a decrease in mechanical properties. Composite ingots are ingots cast from the melting and mixing of aluminum cans. They have already undergone a refining process during melting. Therefore, using composite ingots to formulate 6082 aluminum alloy makes it easier to obtain ingots with good metallurgical quality.

[0086] Comparative Example 3, based on the process scheme of Example 2, changed the refining agent and used conventional chloride salt solvents for melt refining. Because the refining agent did not contain fluoride salts, and especially did not contain cryolite, it failed to fully dissolve the oxide film in the recycled aluminum melt, resulting in a significant decrease in the alloy's mechanical properties, particularly the plasticity index (A). gt() decreased significantly.

[0087] Comparative Example 4 is based on the process scheme of Example 2, but the modifier is changed to conventional Al-5Ti-B aluminum alloy rod material. Due to the lower degree of grain refinement, the yield strength and elongation of the final profile both decrease.

[0088] Comparative Example 5, based on the process scheme of Example 2, changed the refining agent to a previously reported porous granular refining agent containing SiO2, with the following mass fraction ratio: KCl:MgCl2:CaF2:Na3AlF6:SiO2 = 45%:40%:5%:5%:5%. Because the refining agent contained relatively little cryolite, it failed to fully dissolve the oxide film in the recycled aluminum from beverage cans. Furthermore, the SiO2 in the refining agent may have undergone specific reactions with certain components in the melt, leading to a decrease in the final mechanical properties of the alloy, especially the plasticity index (A). gt () decreased significantly.

[0089] The present invention has been described in detail above with reference to the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for preparing 6082 aluminum alloy, characterized in that, Includes the following steps: S1. First, melt the aluminum composite ingots from the aluminum cans into molten aluminum, then add aluminum ingots, Al-10Mn master alloy, Al-12Si master alloy and magnesium ingots, stir and remove slag to obtain melt I; S2. Melt I, refining agent and modifier are mixed and refined and modified. After stirring and slag removal, melt II is obtained. S3. The melt II is sequentially filtered, cast, homogenized, deformed, solution treated and aged heat treated to obtain 6082 aluminum alloy. Relative to 100 parts by weight of the aluminum ingot from the recycled aluminum can, the aluminum ingot contains 80-85 parts by weight; the Al-10Mn master alloy contains 3.8-4.2 parts by weight; the Al-12Si master alloy contains 9.5-11.5 parts by weight; and the magnesium ingot contains 1.2-1.4 parts by weight. The refining agent comprises the following components by mass percentage: KCl: 30~40%; MgCl2: 20~30%; NaF: 5~10%; CaF2: 5~15%; Na3AlF6: 25~35%; the sum of the contents of all components is 100%; The modifier is an Al-3Ti aluminum alloy containing 15~25 wt.% TiB2 particles.

2. The preparation method according to claim 1, characterized in that, Based on the total mass of the aluminum composite ingots from the beverage cans, aluminum ingots, Al-10Mn master alloy, Al-12Si master alloy, and magnesium ingots, the refining agent accounts for 1.5 to 3.0% of the total mass.

3. The preparation method according to claim 1, characterized in that, Based on the total mass of the aluminum composite ingots from the beverage cans, aluminum ingots, Al-10Mn master alloy, Al-12Si master alloy, and magnesium ingots, the modifier accounts for 1.5 to 2.5% of the total mass.

4. The preparation method according to claim 1, characterized in that, In step S1, the melting temperature is 710~750℃.

5. The preparation method according to claim 1, characterized in that, The aging heat treatment temperature is 150~200℃.

6. The preparation method according to claim 1, characterized in that, The aging heat treatment time is 6~10h.

7. The preparation method according to claim 1, characterized in that, The solution treatment temperature is 520℃~540℃.

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