5182 alloy can cover material with high recycled aluminum ratio and preparation method thereof

Abstract

The invention belongs to the technical field of aluminum alloy materials, discloses a high-aluminum-recovery-ratio 5182 alloy can cover material suitable for packaging materials such as easy-open covers and a preparation method of the high-aluminum-recovery-ratio 5182 alloy can cover material, and solves the problem of organization heredity when high-ratio recovered aluminum is applied. The method comprises the steps of raw material proportioning (70%-80% of recycled aluminum materials and 35%-45% of bright aluminum wires), smelting pretreatment, melt treatment, casting and hot rolling and cold rolling. By controlling the mass ratio of Mn / Fe to be 1.5-2.0 and adopting online degassing and ceramic filter combined purification, the hydrogen content is smaller than or equal to 0.10 mL / 100 gAl, the final finished product has a uniform and fine microstructure and is free of obvious needle-shaped harmful phases, various properties completely meet the requirements of high-end tank cover materials, and cost and carbon emission are remarkably reduced.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aluminum alloy materials, and particularly relates to a high-recovery aluminum proportion 5182 alloy can end material for packaging materials such as easy-open cans and a preparation method thereof. BACKGROUND

[0002] In the aluminum processing industry, in order to realize green recycling and reduce costs, increasing the use proportion of recycled aluminum in high-end aluminum plate and strip materials (such as can end materials) has become an important development direction. However, recycled aluminum materials, especially scrap aluminum wire and scrap can bodies with complex sources, usually contain high impurity elements such as Fe and Si, and may carry oxides and oil stains. In the remelting and casting process, these factors are extremely easy to cause the "organization inheritance" phenomenon, that is, the defects such as harmful phases (such as needle-shaped βAl5FeSi) and oxide inclusions in the old material are inherited into the new cast ingot, which seriously damages the mechanical properties (especially plasticity and elongation), surface quality (peeling and lines) and anodic oxidation uniformity of the final product.

[0003] At present, the industry generally holds a conservative attitude towards the use of recycled materials. In high-quality can end materials, the addition proportion of recycled materials is generally strictly limited to a low level (such as below 30%) to avoid the above risks. This limits the further development of the sustainability and cost advantage of aluminum materials. Therefore, it is of important technical and economic value to develop a process method that can break through this limitation and stably produce high-recovery-proportion, high-performance can end materials. SUMMARY

[0004] The purpose of the application is to provide a preparation method of a high-recovery-aluminum-proportion 5182 alloy can end material, which effectively solves the organization inheritance problem when high-proportion recycled aluminum is applied.

[0005] To solve the above technical problems, the technical scheme adopted by the present application is: a preparation method of high-recycled-aluminum-proportion 5182 alloy can cover material, comprising the following steps: S1, raw material proportioning: based on the total amount of raw materials, the following components are included: 70%-80% recycled aluminum material, wherein the bright aluminum wire accounts for 35%-45%; 20%-25% electrolytic aluminum liquid; and alloying element additives; S2, smelting and pretreatment: the recycled aluminum material is sorted and pretreated to remove surface foreign matter, oil stains and moisture, and then the prepared raw materials are put into a smelting furnace for smelting; S3, melt treatment: a spectrometer is used for on-site rapid analysis, the chemical composition is accurately adjusted to ensure that it meets the standard of 5182 alloy, and the Fe content is controlled to be less than or equal to 0.25%, and the Si content is controlled to be less than or equal to 0.10%; an intermediate alloy high-energy manganese additive is added to control the mass ratio of Mn / Fe in the melt to be 1.5-2.0, so as to promote the transformation of needle-shaped βAl5FeSi phase to more granular αAl(Fe, Mn)Si phase; an online degassing system and a ceramic foam filter are used for combined purification to reduce the hydrogen content of the melt to below 0.10 mL / 100 g Al and effectively remove oxidized inclusions; before casting, an AlTiB grain refiner is added to obtain fine and uniform equiaxed crystal structure; S4, casting; S5, hot rolling and cold rolling.

[0006] Further, in step S2, the recycled aluminum material pretreatment process is: grading and sorting of bright aluminum wire, high-temperature degreasing of 120-150 DEG C for 30-40 min, and vacuum drying under the condition of vacuum degree ≤-0.09 MPa and temperature of 80-100 DEG C.

[0007] Further, in step S3, the addition speed of the AlTiB grain refiner is 260 cm / min.

[0008] Further, in step S4, the treated melt is subjected to direct current casting, and the casting temperature is controlled to be 680-695 DEG C to obtain a 5182 alloy ingot.

[0009] Further, in step S5, the 5182 alloy ingot is subjected to face milling, homogenization annealing, hot rolling, cold rolling and intermediate annealing, and finally rolled to the target thickness.

[0010] Another object of the present application is to provide a high-recycled-aluminum-proportion 5182 alloy can cover material prepared by the preparation method described in the above embodiments.

[0011] Further, the mass percentage of the chemical composition is: Si ≤0.10%, Fe ≤0.25%, Cu ≤0.06%, Mn 0.35-0.40%, Mg 4.60-4.65%, Cr ≤0.03%, Zn ≤0.03%, Ti ≤0.02%, other single impurities ≤0.03%, total sum of other impurities ≤0.15%, and the balance is Al.

[0012] Furthermore, it has a uniform and fine microstructure, without obvious needle-like harmful phases.

[0013] Compared with the prior art, the beneficial technical effects of the present invention are: (1) Significant environmental and cost advantages: The present invention increases the total proportion of recycled aluminum to 70%-80%, of which the proportion of single recycled material of bright aluminum wire reaches 35%-45%, which is more than twice the industry standard level. The raw material cost per ton of product is reduced by 15%-20%, and carbon emissions are reduced by about 30%, which is in line with the green manufacturing development trend.

[0014] (2) Breakthrough in core technical challenges: This invention completely solves the problem of “organic inheritance” in the application of high-recycle aluminum through the combination of “raw material pretreatment + composition regulation + melt refining” technology. The final product has no obvious needle-like harmful phases, the anodizing rating reaches grade B, and the surface has no defects such as peeling or lines, meeting the stringent surface quality requirements of high-end can lid materials.

[0015] (3) Excellent performance and stability: The final product prepared by this invention has stable mechanical properties, with tensile strength of 378-386MPa, yield strength of 330-336MPa, and elongation of 7.0-8.5%. There is no cracking or wrinkling after deep drawing. After baking at 205℃ for 20min, the performance decay rate is ≤5%. The long-term stability is better than that of similar products prepared with all primary aluminum.

[0016] (4) Strong process scalability: The entire process of this invention has been industrialized and can be adapted to the production of 5182 can lids of different specifications. It can also be extended to other high-end application scenarios of aluminum alloy recycled materials (such as aluminum packaging and lightweight automotive parts), with broad application prospects. Attached Figure Description

[0017] Figure 1 The images show the metallographic structure of the 5182 alloy ingot prepared in Example 1, where image a is the compound and image b is the high-magnification grain.

[0018] Figure 2 The images show the metallographic structure of the 5182 alloy ingot prepared in Comparative Example 1, where image a represents the compound and image b represents the high-magnification grains. Detailed Implementation

[0019] Example 1: The goal of this example is to produce 5182 alloy can lid material with a high recycled aluminum ratio for customer A.

[0020] The raw material ratio in this embodiment (taking DP764 casting as an example) is as follows: Total feed amount: 80605 kg. This includes 31600 kg (39.20%) of bright aluminum wire, 15764 kg (19.56%) of 3104 grade II purchased white aluminum, approximately 10% internal scrap (sawed ends of ingots, rolled ends, and trimming scrap), 19450 kg (24.13%) of electrolytic aluminum liquid, and 10522 kg (13.06%) of 5182 grade I material, plus alloying elements such as Mg and Mn. The total solid material ratio is 75.87%, and the total scrap ratio is 71.81%.

[0021] The preparation process of the high recycled aluminum ratio 5182 alloy can lid material in this embodiment is as follows: (1) Sorting and pre-treatment of recycled aluminum materials such as bright aluminum wire to remove surface foreign matter, oil stains and moisture, and then putting the prepared raw materials into the smelting furnace for smelting.

[0022] Specifically, the pretreatment process for recycled aluminum is as follows: grading and sorting of bright aluminum wire, high-temperature degreasing at 120-150℃ for 30-40 minutes, and vacuum drying under vacuum conditions of ≤-0.09MPa and temperature of 80-100℃.

[0023] (2) Add materials according to the proportion and smelt, and keep warm for 65 minutes.

[0024] (3) A rapid pre-furnace analysis was performed using a spectrometer, and the chemical composition was precisely adjusted to: Si 0.0814%, Fe 0.216%, Mn 0.3597%, Mg 4.605%.

[0025] Adding high-energy manganese additives to the intermediate alloy controls the Mn / Fe mass ratio in the melt to 1.5-2.0, promoting the transformation of the acicular βAl5FeSi phase to the more agglomerated αAl(Fe,Mn)Si phase.

[0026] (4) Online degassing system (such as SNIF, ALPUR) is used for online degassing and ceramic foam filter (CFF, preferably 40+50PPI) is used for combined purification to reduce the hydrogen content of the melt to 0.095mL / 100gAl and effectively remove oxide inclusions.

[0027] (5) Before casting, add domestic AMG AlTi5B0.2 grain refiner at a rate of 260 cm / min to obtain a fine equiaxed grain structure with an average grain size of 146.09-205.73 μm, thereby suppressing the performance inhomogeneity caused by coarse grains.

[0028] (6) The melt processed by the above steps is subjected to DC casting at a casting temperature of 692℃ to obtain 5182 alloy ingot.

[0029] (7) After milling, the 5182 alloy ingot is homogenized and annealed at 580-620℃ and held for 8-10 hours to ensure that the second phase is fully dissolved and dispersed; hot rolling at 325-345℃ to roll the ingot to a thickness of 2.5mm to ensure uniform grain breakage; cold rolling adopts the strategy of "multi-pass small deformation" to finally roll into a finished 5182 alloy can lid material with a thickness of 0.208mm.

[0030] The chemical composition (mass percentage) of the high-recovery-aluminum-ratio 5182 alloy can lid material prepared in this embodiment is as follows: Si≤0.10%, Fe≤0.25%, Cu≤0.06%, Mn 0.35-0.40%, Mg 4.60-4.65%, Cr≤0.03%, Zn≤0.03%, Ti≤0.02%, other individual impurities≤0.03%, total of other impurities≤0.15%, and the balance is Al. This ensures deep-drawing performance while suppressing the adverse effects of impurity elements on the matrix. Testing showed that the content of heavy metals such as Pb, Cd, and Hg in the high-recovery-aluminum-ratio 5182 alloy can lid material prepared in this embodiment meets national safety standards, balancing performance and environmental compliance.

[0031] The performance indicators of the high-recycled aluminum ratio 5182 alloy can lid material prepared in this embodiment are: tensile strength 382.65 MPa, elongation 7.5%, and hot-rolled finished product anodizing rating grade B. For example... Figure 1 As shown, the high-recovery-aluminum-ratio 5182 alloy can lid compound prepared in this embodiment is uniformly and finely dispersed, with no obvious needle-like harmful phases.

[0032] Comparative Example 1: 5182 alloy ingots were prepared using the same raw material ratios as in Example 1, but without employing the complete process of Example 1. Instead, they were prepared using conventional methods (batching → charging → melting → slag removal → alloy addition → stirring → sampling → slag removal → composition adjustment → converter → in-furnace refining → sampling → slag removal → temperature adjustment → grain refinement → online degassing → filtration → casting). Figure 2 As shown, the metallographic structure of the 5182 alloy ingot in this comparative example exhibits obvious acicular β phase, resulting in poor product surface quality that fails to meet customer requirements.

[0033] This invention successfully solves the microstructure inheritance problem in the application of high-proportion recycled aluminum through an integrated solution of raw material pretreatment, melt purification, precise component control and process optimization. It achieves stable production of 5182 can lid material with a recycled material ratio of 70%-80% (of which, the single recycled material ratio of bright aluminum wire reaches 35%-45%), and the performance of the product fully meets the requirements of high-end customers.

[0034] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method of producing a high-recycled-aluminum-ratio 5182 alloy can lid stock, characterized by, The method comprises the following steps: S1, raw material proportioning: based on the total amount of raw materials, the following components are included: 70%-80% recycled aluminum material, wherein the bright aluminum wire accounts for 35%-45%; 20%-25% electrolytic aluminum liquid; and alloying element additives; S2, smelting and pretreatment: the recycled aluminum material is sorted and pretreated to remove surface foreign matter, oil stains and moisture, and then the prepared raw materials are put into a smelting furnace for smelting; S3, melt treatment: a spectrometer is used for rapid analysis before the furnace, the chemical composition is accurately adjusted to ensure that it meets the standard of 5182 alloy, and the Fe content is controlled to be ≤0.25% and the Si content is controlled to be ≤0.10%; high-energy manganese additive is added to the intermediate alloy to control the mass ratio of Mn / Fe in the melt to be 1.5-2.0, so as to promote the transformation of needle-shaped βAl5FeSi phase to more globular αAl(Fe, Mn)Si phase; An online degassing system and a ceramic foam filter are used for combined purification to reduce the hydrogen content of the melt to below 0.10 mL / 100 g Al and effectively remove oxidized inclusions; Before casting, AlTiB grain refiner is added to obtain fine and uniform equiaxed crystal structure; S4, casting; S5, hot rolling and cold rolling.

2. The method of making high-recycle aluminum ratio 5182 can lid stock of claim 1, wherein, In step S2, the pretreatment process of the recycled aluminum material is: grading and sorting of the bright aluminum wire, high-temperature degreasing at 120-150°C for 30-40 min, and vacuum drying under the condition of vacuum degree ≤-0.09 MPa and temperature of 80-100°C.

3. The method of making high-recycle aluminum ratio 5182 can body stock of claim 2, wherein, In step S3, the addition speed of AlTiB grain refiner is 260 cm / min.

4. The method of making high-recycle aluminum ratio 5182 can lid stock of claim 3, wherein, In step S4, the treated melt is subjected to direct current casting, and the casting temperature is controlled to be 680-695°C to obtain 5182 alloy ingot.

5. The method of making high-recycle aluminum ratio 5182 can body stock of claim 4, wherein, In step S5, the 5182 alloy ingot is subjected to face milling, homogenization annealing, hot rolling, cold rolling and intermediate annealing, and finally rolled to the target thickness.

6. A high-recycled-aluminum ratio 5182 alloy can lid stock characterized by, Prepared by the preparation method of any one of claims 1-5.

7. The high-recycle aluminum ratio 5182 alloy can body material according to claim 6, characterized in that, The chemical composition is as follows: Si ≤0.10%, Fe ≤0.25%, Cu ≤0.06%, Mn 0.35-0.40%, Mg 4.60-4.65%, Cr ≤0.03%, Zn ≤0.03%, Ti ≤0.02%, other single impurities ≤0.03%, total sum of other impurities ≤0.15%, and the balance is Al.

8. The high-recycle aluminum ratio 5182 alloy can body of claim 7, wherein, It has uniform and fine microstructure and no obvious needle-shaped harmful phase.

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