Method for low-carbon high-efficiency short-process manufacturing of 7072 alloy high-performance air conditioner foil

Abstract

The application introduces a kind of low-carbon high-efficiency short-process manufacturing 7072 alloy high-performance air conditioner foil method, relates to aluminum foil processing technical field, specific steps are as follows: S1: smelting;S2: continuous casting and rolling;S3: cold foil rolling;S4: finished product annealing;S5: inspection and packaging.The application controls iron, silicon alloy elements at the lower limit of national standard by adjusting composition, reduces the generation of coarse aluminum iron silicon phase, avoids the low elongation caused by coarse grain after finished product annealing;Adjust work roll, rolling oil index in cold foil rolling process, optimize process parameters, realize direct rolling from blank to finished product, the direct rolling process is beneficial to improve the mechanical properties of finished product, and is convenient for downstream customer punching production;After three continuous rolling, arrange subsequent cold foil rolling continuous rolling quickly, make full use of deformation heat generated by three continuous rolling and each pass rolling, realize each pass large processing rate rolling.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum foil processing, and in particular to a method for manufacturing 7072 alloy high-performance air-conditioning foil with low carbon, high efficiency and short process. Background Art

[0002] 7072 alloy air-conditioning foil is widely used in the radiators of automobile air conditioners. This is because 7072 alloy contains an appropriate amount of zinc, which can reduce the corrosion potential of the alloy and can be used as a sacrificial anode material to protect adjacent pipes and extend the service life of the radiator. At the same time, 7072 alloy has good processing performance and has excellent mechanical properties after a series of processing. Air-conditioning radiators made of 7072 alloy air-conditioning foil have good corrosion resistance and a long service life, and can adapt to different usage environments and working conditions.

[0003] As people's requirements for air-conditioning performance and quality continue to increase, as well as their emphasis on environmental protection and energy conservation, the market demand for corrosion-resistant, high-performance 7072 alloy air-conditioning foil is expected to increase further; especially in some areas with high requirements for air-conditioning service life and reliability, such as high-end household air-conditioning, automotive air-conditioning and large-scale commercial air-conditioning systems, 7072 alloy air-conditioning foil will have a broader application space.

[0004] In recent years, some companies have used the casting and rolling method and the continuous casting and rolling method to produce 7072 alloy air-conditioning foil. The production process flow of 7072 alloy air-conditioning foil products using the casting and rolling method is roughly as follows: smelting → casting and rolling → homogenization annealing → 5 passes of cold rolling → intermediate annealing → 2 passes of foil rolling → finished product annealing → inspection and packaging; the production process flow of 7072 alloy air-conditioning foil products using the continuous casting and rolling method is as follows: smelting → continuous casting and rolling → homogenization annealing → 9 passes of cold foil rolling → finished product annealing; generally speaking, the production of 7072 alloy air-conditioning foil using the above two methods requires high-temperature homogenization annealing, and the casting and rolling method also requires secondary annealing; the aforementioned process scheme requires one or two intermediate annealings, which will cause a sharp increase in production costs and extended production time. At the same time, it will face the hidden danger of insufficient mechanical properties of the finished product, affecting the use of aluminum foil punching, and causing problems such as cumbersome post-processing technology and low yield. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a low-carbon, high-efficiency, short-process method for manufacturing 7072 alloy high-performance air-conditioning foil, simplify the process flow, reduce the number of cold foil rolling production passes, and achieve low-carbon, high-efficiency, short-process production.

[0006] The technical solution adopted in the present invention is:

[0007] A method for manufacturing 7072 alloy high-performance air-conditioning foil in a low-carbon, high-efficiency and short process, comprising the following steps:

[0008] S1: Smelting; 60-70% by mass of electrolytic aluminum liquid, 20-30% of remelted aluminum ingots and 5-10% of recycled aluminum scrap are placed in a smelting furnace for remelting to prepare an aluminum melt. The melt temperature of the smelting furnace is 770±5°C. Iron agent, quick-dissolving silicon, titanium agent and zinc ingot are added to the smelting furnace to adjust the alloy composition to meet the requirements. The mass percentages of the components are as follows: Si: 0.05-0.10%, Fe: 0.1-0.15%, Cu: ≤0.02%, Zn: 0.8-0.9%, Ti: 0.015-0.025%, other individual impurities ≤0.03% and total ≤0.15%, and the balance is Al;

[0009] After refining, slagging and standing, the aluminum melt is qualified and ready for furnace starting. The melt flows into the degassing box through the diversion flow channel for online degassing, and then is filtered online through the plate filter box. The hydrogen content of the melt after degassing and filtration is ≤0.15ml / 100gAl, and the alkali metal Na content is ≤2ppm.

[0010] S2: Continuous casting and rolling: The aluminum melt in the front box flows uniformly through the casting nozzle between the two steel belts, and the aluminum melt solidifies in the casting cavity to form a cast billet. During continuous casting, the front box temperature is maintained at 700±10℃, the casting speed is controlled at 7.2-7.8m / min, the billet thickness is controlled at 19±1mm, and the billet width is controlled at 1635±5mm.

[0011] The slab enters the three-pass continuous rolling mill for rolling. The roughness of the work rolls in the first pass is 3-4µm, the rolling processing rate is controlled at 55-65%, and the slab outlet thickness is 6.7-8.5mm. The roughness of the work rolls in the second pass is 1-2µm, the rolling processing rate is controlled at 45-55%, and the slab outlet thickness is 3.3-3.8mm. The roughness of the work rolls in the third pass is 0.5-0.7µm, the rolling processing rate is controlled at 40-50%, the slab outlet thickness is 1.7-2.2mm, the outlet speed is controlled at 67-87m / min, and the final rolling temperature is controlled above 200℃.

[0012] S3: Cold foil rolling: The aluminum coils after the three-pass rolling are transferred to the cold rolling unit without cooling for rolling, and the processing rate of each cold rolling pass is controlled at 50-60%;

[0013] During the second rolling pass, the aluminum coil is trimmed using the trimming device provided with the rolling mill. After trimming, the aluminum coil is directly rolled into a 0.15-0.25mm cold-rolled coil.

[0014] The 0.15-0.25mm cold rolled coil is foil rolled at a processing rate of 50-60%, and the aluminum foil coil with a thickness of 0.09-0.12mm is rolled. The thickness tolerance of the aluminum foil is ±4%.

[0015] S4: Finished product annealing: Place the 0.09-0.12mm aluminum foil coil into the annealing furnace for finished product annealing, heat it to 220-250°C in 2 hours, keep it under negative pressure for 4-6 hours to remove oil; heat it to 260-330°C in 2-4 hours, keep it under positive pressure for 25-35 hours, then remove it from the furnace when the temperature drops to 170°C and let it cool naturally to room temperature;

[0016] S5: Inspection and packaging; check that the thickness and width of the aluminum foil must not exceed the tolerance range, the end face must not have burrs, flanges, or bumps, and the layer misalignment must not exceed 0.5mm. The finished aluminum foil product is tested to have a tensile strength of 100-110Mpa and an elongation of ≥28% and is qualified. It is then packaged after passing the test.

[0017] Specifically, after adding iron agent, quick-dissolving silicon and titanium agent to the S1, electromagnetic stirring is turned on until the melt composition is uniform; after the furnace is started, the aluminum melt flows smoothly into the guide flow channel, and aluminum titanium boron wire is added to the melt at a uniform speed.

[0018] Specifically, in S2, before the steel strip contacts the aluminum liquid, it is evenly sprayed with nano-scale silicon dioxide powder by the ESP device to provide thermal insulation protection for the steel strip; and the steel strip is heated by electromagnetic induction to eliminate moisture on the surface of the steel strip.

[0019] Specifically, the ingot produced in S2 is required to have a flat shape, a thickness difference of ≤±1% throughout the roll, a layer thickness of less than 5mm, and a tower thickness of less than 10mm; the surface aluminum ash of the ingot needs to be strictly controlled to avoid serious black wire and black strip problems in the subsequent rolling process.

[0020] Specifically, in the S3, a working roll with a crown of 10µm is used during cold rolling, and the additive content in the rolling oil is ≥16%; the disc cutter is required to be wiped with a clean rag before trimming, and the trimming quality requires smooth edges, no aluminum powder, and no warping; a working roll with a crown of 8µm is used during foil rolling, and the additive content in the rolling oil is ≥12%.

[0021] Specifically, during the annealing of the finished product in S4, the axial flow fan is required to rotate at a speed of 500 r / min to achieve a temperature difference of less than 3° C. in each area of ​​the furnace.

[0022] Due to the adoption of the above technical solution, the present invention has the following advantages:

[0023] 1. By adjusting the composition, the iron and silicon alloy elements are controlled within the lower limit of the national standard, reducing the generation of coarse aluminum-iron-silicon phases and avoiding low elongation due to coarse grains after annealing of the finished product; at the same time, the zinc element is also controlled within the lower limit of the national standard to weaken the alloy strengthening effect, reduce the subsequent deformation resistance, and avoid problems such as edge cracking during continuous rolling;

[0024] 2. Adjusting work roll and rolling oil index in cold foil rolling process, optimizing process parameters, realizing direct rolling from blank to finished product, which is beneficial to improve the mechanical properties of finished product and facilitate the punching production of downstream customers;

[0025] 3. Increasing the casting machine speed of blank production, ensuring the final rolling temperature of three-stand rolling finished product above 200℃, improving metal plasticity, reducing deformation resistance, and facilitating subsequent cold foil rolling;

[0026] 4. Quickly arranging subsequent cold foil rolling after three-stand rolling, fully utilizing the deformation heat generated by three-stand rolling and each pass rolling, and realizing large reduction rolling in each pass;

[0027] 5. Adjusting three-stand rolling production parameters to realize three-stand rolling blank thinning production, and rolling to finished product in 4 passes in subsequent process, which greatly reduces production cost;

[0028] 6. Using 60%-70% high proportion of electrolytic aluminum liquid to prepare aluminum melt, and adopting appropriate melt refining process to treat, so that the quality of aluminum melt can be completely equivalent to that of melt produced by using remelted aluminum ingot. This production scheme can save the electrolytic aluminum water ingot remelting process, and each ton of product can save about 1% of metal aluminum burning loss, 30kW·h of electric energy, 9-12 tons of production water and 60 cubic meters of natural gas;

[0029] 7. The production scheme adopts blank direct rolling production method, reasonably allocates process parameters, realizes large reduction rolling, and can save 300kW·H of homogenization annealing power consumption compared with the existing technical scheme which must pass through blank homogenizing production method, and can also reduce more than 5 days of production time, realizes high efficiency, short process production and fast delivery. DETAILED DESCRIPTION

[0030] The application will be further explained and described below in conjunction with examples, which cannot limit the protection scope of the application. The purpose of disclosing the application is to protect all technical improvements within the scope of the application. Example 1

[0031] A method for manufacturing 7072 alloy high-performance air conditioning foil with low carbon and high efficiency and short process, the specific steps are:

[0032] S1: smelting; 60% by mass of electrolytic aluminum liquid, 30% of remelted aluminum ingots and 10% of recycled aluminum scrap are put into a smelting furnace for remelting to prepare an aluminum melt. The melt temperature of the smelting furnace is 770±5°C. Iron agent, instant silicon, titanium agent and zinc ingot are added to the smelting furnace. Electromagnetic stirring is turned on to ensure that the melt is fully stirred. The alloy composition is adjusted to meet the requirements, wherein the mass percentage of each component is: Si: 0.05%, Fe: 0.1%, Cu: 0.012%, Zn: 0.8%, Ti: 0.015%, other individual impurities ≤ 0.03%, total ≤ 0.15%, and the balance is Al;

[0033] After refining, slagging and standing, aluminum melt is obtained; after starting the furnace, the aluminum melt flows smoothly into the diversion trough, and four groups of aluminum titanium boron wires are added to the melt at a uniform speed. The melt is introduced into the SNIF degassing box through the diversion trough for online degassing, and then filtered online through the plate filter box. The hydrogen content of the melt after degassing and filtration is 0.12ml / 100gAl, and the alkali metal Na content is 1ppm.

[0034] S2: Continuous casting and rolling. During continuous casting, the aluminum melt in the front box flows through the casting nozzle at a uniform speed between two steel strips. Before the steel strips come into contact with the aluminum liquid, they are sprayed with a uniform layer of nano-scale silicon dioxide powder by an ESP device to provide thermal insulation and protection. In addition, the steel strips are heated by electromagnetic induction to remove moisture from the surface.

[0035] Under the combined action of two steel belts and two pairs of side blocks, the heat of the aluminum melt is carried away by the circulating cooling water inside the steel belts, and the aluminum melt solidifies in the casting cavity to form a billet. During continuous casting, the front box temperature must be maintained at 710°C, the casting speed is controlled at 7.2m / min, the billet thickness is controlled at 19mm, and the billet width is controlled at 1630mm.

[0036] The ingot enters the three-pass continuous rolling mill for rolling. The roughness of the working rolls in the first pass is 3-4µm, the rolling processing rate is controlled at 55-65%, and the slab outlet thickness is 6.7mm; the roughness of the working rolls in the second pass is 1-2µm, the rolling processing rate is controlled at 45-55%, and the slab outlet thickness is 3.4mm; the roughness of the working rolls in the third pass is 0.5-0.7µm, the rolling processing rate is controlled at 40-50%, the slab outlet thickness is 1.7mm, the outlet speed is controlled at 80m / min, and the final rolling temperature is 223℃; the slab is required to have a layer string less than 5mm, a tower shape less than 10mm, a flat plate, and a thickness difference of ≤±1% for the whole roll. The surface aluminum ash is strictly controlled to avoid serious black wire and black strip problems in the subsequent rolling process.

[0037] S3: Cold foil rolling; after three continuous rolling, the aluminum coil is not cooled and quickly transported to the cold rolling unit for rolling. The work roll crown used in cold rolling is 10 pm, the additive content in the rolling oil is ≥16%, the rolling pass rate is controlled at 50-60%, and the rolling pass is 1.7-0.8-0.37-0.18. When rolling to 0.37 mm, the edge of the aluminum coil is cut using the edge cutting device matched with the rolling mill;

[0038] Before cutting, a clean cloth is required to wipe the disc knife. The cutting quality requirements are smooth edge, no aluminum powder, no edge lifting, and the edge after cutting should be smooth and free of burrs. The aluminum coil after cutting is directly rolled to 0.18 mm cold rolled coil;

[0039] The 0.18 mm cold rolled coil is foil rolled at a processing rate of 50-60%. The work roll crown used in foil rolling is 8 pm, and the additive content in the rolling oil is ≥12%. The foil rolling produces an aluminum foil coil with a thickness of 0.09 mm, and the aluminum foil thickness tolerance is ±4%. The production of aluminum foil finished product requires control of the surface oil content, and there should be no visible oil spots and oil marks.

[0040] S4: Product annealing; first seal with high-temperature-resistant aluminum foil tape to ensure that the layers cannot be loose, then load the furnace for annealing, place the 0.09 mm aluminum foil coil into the annealing furnace for product annealing, the axial flow fan requires a speed of 500 r / min to achieve a temperature difference of <3°C in each area of the furnace; heat up to 220°C for 2 hours, deoxygenate for 4 hours under negative pressure, heat up to 285°C for 2 hours, and then heat under positive pressure for 28 hours, then take out the furnace when the furnace temperature drops to 170°C, and naturally cool to room temperature.

[0041] S5: Inspection and packaging; the aluminum foil thickness and width should not exceed the tolerance range, the end face should be free of burrs, edge lifting and impact damage, the layering error should not exceed 0.5 mm, the tensile strength of the aluminum foil finished product should reach 100 Mpa, the elongation should be 28%, and the product is determined to be qualified. After being determined to be qualified, it is packaged. Comparative Example 1

[0042] Comparative Example 1 uses the existing technology process of melting → continuous casting and rolling → homogenization annealing → 9-pass cold foil rolling → product annealing, and produces a product with a thickness of 0.095 mm corresponding to Example 1. The performance is: tensile strength 110 / Mpa, elongation 20%. Example 2

[0043] A method for manufacturing 7072 alloy high-performance air conditioning foil with low carbon and high efficiency and short process, the specific steps are:

[0044] S1: smelting; 70% by mass of electrolytic aluminum liquid, 25% of remelted aluminum ingots and 5% of recycled aluminum scrap are put into a smelting furnace for remelting to prepare an aluminum melt. The melt temperature of the smelting furnace is 770±5°C. Iron agent, instant silicon, titanium agent and zinc ingot are added to the smelting furnace. Electromagnetic stirring is turned on to ensure that the melt is fully stirred. The alloy composition is adjusted to meet the requirements, wherein the mass percentage of each component is: Si: 0.10%, Fe: 0.15%, Cu: 0.012%, Zn: 0.9%, Ti: 0.025%, other individual impurities ≤ 0.03%, total ≤ 0.15%, and the balance is Al;

[0045] After refining, slagging and standing, aluminum melt is obtained; after starting the furnace, the aluminum melt flows smoothly into the diversion trough, and four groups of aluminum titanium boron wires are added to the melt at a uniform speed. The melt is introduced into the SNIF degassing box through the diversion trough for online degassing, and then filtered online through the plate filter box. The hydrogen content of the melt after degassing and filtration is 0.15ml / 100gAl, and the alkali metal Na content is 2ppm.

[0046] S2: Continuous casting and rolling. During continuous casting, the aluminum melt in the front box flows through the casting nozzle at a uniform speed between two steel strips. Before the steel strips come into contact with the aluminum liquid, they are sprayed with a uniform layer of nano-scale silicon dioxide powder by an ESP device to provide thermal insulation and protection. In addition, the steel strips are heated by electromagnetic induction to remove moisture from the surface.

[0047] Under the combined action of two steel belts and two pairs of side blocks, the heat of the aluminum melt is carried away by the circulating cooling water inside the steel belts, and the aluminum melt solidifies in the casting cavity to form a billet. During continuous casting, the front box temperature must be maintained at 690°C, the casting speed is controlled at 7.8m / min, the billet thickness is controlled at 19mm, and the billet width is controlled at 1640mm.

[0048] The ingot enters the three-pass continuous rolling mill for rolling. The roughness of the working rolls in the first pass is 3-4µm, the rolling processing rate is controlled at 55-65%, and the slab outlet thickness is 8.0mm; the roughness of the working rolls in the second pass is 1-2µm, the rolling processing rate is controlled at 45-55%, and the slab outlet thickness is 3.8mm; the roughness of the working rolls in the third pass is 0.5-0.7µm, the rolling processing rate is controlled at 40-50%, the slab outlet thickness is 2.2mm, the outlet speed is controlled at 67m / min, and the final rolling temperature is 235℃; the slab is required to have a layer string less than 5mm, a tower shape less than 10mm, a flat plate, and a thickness difference of ≤±1% for the whole roll. The surface aluminum ash is strictly controlled to avoid serious black wire and black strip problems in the subsequent rolling process.

[0049] S3: Cold foil rolling: After the three-pass rolling, the aluminum coil is quickly transferred to the cold rolling unit without cooling. During cold rolling, the work roll crown is 10µm, the additive content in the rolling oil is ≥16%, and the processing rate of each cold rolling pass is controlled at 50-60%. The specific rolling passes are: 2.2-1.0-0.5-0.25. When rolling 0.5mm, the aluminum coil is trimmed using the trimming device equipped with the rolling mill;

[0050] Before trimming, the disc knife must be wiped with a clean rag. The trimming quality requires smooth edges, no aluminum powder, and no warping. The edges must be smooth and burr-free after trimming. The aluminum coils after trimming are directly rolled into 0.25mm cold-rolled coils.

[0051] 0.25mm cold-rolled coils are foil rolled at a processing rate of 50-60%. The working roll crown is 8µm and the additive content in the rolling oil is ≥12%. The foil rolling produces aluminum foil coils with a thickness of 0.12mm and a thickness tolerance of ±4%. The finished aluminum foil is required to have controlled surface oil content and no visible oil spots or oil marks.

[0052] S4: Annealing of finished products; first seal with high-temperature resistant aluminum foil tape to ensure that there is no loose layer before loading the material rack into the furnace for annealing, place the 0.12mm aluminum foil roll into the annealing furnace for finished product annealing, the axial flow fan is required to rotate at 500r / min to achieve a temperature difference of less than 3°C in each area of ​​the furnace; heat up to 220°C in 2 hours, keep under negative pressure for 4 hours to remove oil, heat up to 285°C in 2 hours, keep under positive pressure for 28 hours, then remove from the furnace when the furnace temperature drops to 170°C and cool naturally to room temperature.

[0053] S5: Inspection and packaging; check that the thickness and width of the aluminum foil must not exceed the tolerance range, the end face must not have burrs, flanges, or bumps, and the layer misalignment must not exceed 0.5mm. The finished aluminum foil product must have a tensile strength of 100Mpa and an elongation of 32%. It will be qualified and packaged after it is qualified. Comparative Example 2

[0054] Comparative Example 2 adopts the existing process flow of smelting → continuous casting and rolling → homogenization annealing → 9-pass cold foil rolling → finished product annealing to produce the same 0.12 mm thick product as Example 2 with the following properties: tensile strength 95 / Mpa, elongation 27%.

[0055] Table 1 is a performance comparison table of products produced by the technical solutions of Examples 1 and 2 of the present invention and the technical solutions of Comparative Examples 1 and 2.

[0056] Table 1

[0057] Thickness / mm Tensile strength / Mpa Elongation / % Example 1 0.09 100 28 Comparative Example 1 0.095 110 20 Example 2 0.12 100 32 Comparative Example 2 0.12 95 27

[0058] From the comparison of the data in Table 1, it can be seen that the 0.09mm thick material produced by the technical solution of the present invention has a higher elongation than the 0.095mm thick material produced by the solution of Comparative Example 1. For the same 0.12mm thick material produced by Example 2 of the present invention, the elongation of the product produced by the present invention is 32%, while the elongation of the material produced by the solution of Comparative Example 2 is only 27%;

[0059] In addition, the tensile strength of the materials produced by the schemes of Comparative Examples 1 and 2 is 95 and 115 MPa, respectively, while the tensile strength of the materials produced by the technical scheme of the present invention is stable at 100 MPa. The stable tensile strength makes it easier for end customers to adjust the punching molds, which is conducive to stable production and stable quality. In summary, the performance of the materials produced by the technical scheme of the present invention is better, more stable, and more suitable for customer use.

[0060] The parts not described in detail in this invention are prior art.

[0061] The embodiments selected herein for the purpose of disclosing the invention are presently considered suitable, but it should be understood that the invention is intended to include all variations and modifications of the embodiments that fall within the scope of the concept and invention.

Claims

1. A method for manufacturing 7072 alloy high-performance air conditioning foil in a low-carbon, high-efficiency and short process, characterized in that: The specific steps are: S1: Smelting; 60-70% by mass of electrolytic aluminum liquid, 20-30% of remelted aluminum ingots and 5-10% of recycled aluminum scrap are placed in a smelting furnace for remelting to prepare an aluminum melt. The melt temperature of the smelting furnace is 770±5°C. Iron agent, quick-dissolving silicon, titanium agent and zinc ingot are added to the smelting furnace to adjust the alloy composition to meet the requirements. The mass percentages of the components are as follows: Si: 0.05-0.10%, Fe: 0.1-0.15%, Cu: ≤0.02%, Zn: 0.8-0.9%, Ti: 0.015-0.025%, other individual impurities ≤0.03% and total ≤0.15%, and the balance is Al; After refining, slagging and standing, the aluminum melt is qualified and ready for furnace starting. The melt flows into the degassing box through the diversion flow channel for online degassing, and then is filtered online through the plate filter box. The hydrogen content of the melt after degassing and filtration is ≤0.15ml / 100gAl, and the alkali metal Na content is ≤2ppm. S2: Continuous casting and rolling: The aluminum melt in the front box flows uniformly through the casting nozzle between the two steel belts, and the aluminum melt solidifies in the casting cavity to form a cast billet. During continuous casting, the front box temperature is maintained at 700±10℃, the casting speed is controlled at 7.2-7.8m / min, the billet thickness is controlled at 19±1mm, and the billet width is controlled at 1635±5mm. The slab enters the three-pass continuous rolling mill for rolling. The roughness of the work rolls in the first pass is 3-4µm, the rolling processing rate is controlled at 55-65%, and the slab outlet thickness is 6.7-8.5mm. The roughness of the work rolls in the second pass is 1-2µm, the rolling processing rate is controlled at 45-55%, and the slab outlet thickness is 3.3-3.8mm. The roughness of the work rolls in the third pass is 0.5-0.7µm, the rolling processing rate is controlled at 40-50%, the slab outlet thickness is 1.7-2.2mm, the outlet speed is controlled at 67-87m / min, and the final rolling temperature is controlled above 200℃. S3: Cold foil rolling: The aluminum coils after the three-pass rolling are transferred to the cold rolling unit without cooling for rolling, and the processing rate of each cold rolling pass is controlled at 50-60%; During the second rolling pass, the aluminum coil is trimmed using the trimming device provided with the rolling mill. After trimming, the aluminum coil is directly rolled into a 0.15-0.25mm cold-rolled coil. The 0.15-0.25mm cold rolled coil is foil rolled at a processing rate of 50-60%, and the aluminum foil coil with a thickness of 0.09-0.12mm is rolled. The thickness tolerance of the aluminum foil is ±4%. S4: Finished product annealing: Place the 0.09-0.12mm aluminum foil coil into the annealing furnace for finished product annealing, heat it to 220-250°C in 2 hours, keep it under negative pressure for 4-6 hours to remove oil; heat it to 260-330°C in 2-4 hours, keep it under positive pressure for 25-35 hours, then remove it from the furnace when the temperature drops to 170°C and let it cool naturally to room temperature; S5: Inspection and packaging; check that the thickness and width of the aluminum foil must not exceed the tolerance range, the end face must not have burrs, flanges, or bumps, and the layer misalignment must not exceed 0.5mm. The finished aluminum foil product is tested to have a tensile strength of 100-110Mpa and an elongation of ≥28% and is qualified. It is then packaged after passing the test.

2. The method for manufacturing 7072 alloy high-performance air-conditioning foil by a low-carbon, high-efficiency, short-process method according to claim 1, characterized in that: After adding iron agent, quick-dissolving silicon and titanium agent into the S1, electromagnetic stirring is fully started; after starting the furnace, the aluminum melt flows smoothly into the guide flow channel, and aluminum titanium boron wire is added into the melt at a uniform speed.

3. The method for producing 7072 alloy high-performance air-conditioning foil with a low-carbon, high-efficiency, short process according to claim 1, characterized in that: In the above-mentioned S2, before the steel strip contacts the aluminum liquid, it is evenly sprayed with nano-scale silicon dioxide powder by the ESP equipment; and the steel strip is heated by electromagnetic induction.

4. The method for manufacturing 7072 alloy high-performance air-conditioning foil with low carbon and high efficiency in a short process according to claim 1 is characterized in that: The ingot produced in S2 is required to have a flat shape, a thickness difference of the entire roll ≤±1%, a layer thickness less than 5mm, and a tower thickness less than 10mm.

5. The method for manufacturing 7072 alloy high-performance air-conditioning foil with low carbon and high efficiency in a short process according to claim 1 is characterized in that: In the S3 described above, a working roll with a crown of 10µm is used during cold rolling, and the additive content in the rolling oil is ≥16%; the disc cutter is required to be wiped with a clean rag before trimming, and the trimming quality requires smooth edges, no aluminum powder, and no warping; a working roll with a crown of 8µm is used during foil rolling, and the additive content in the rolling oil is ≥12%.

6. The method for manufacturing 7072 alloy high-performance air-conditioning foil with low carbon and high efficiency in a short process according to claim 1, characterized in that: During the annealing of the finished product in S4, the axial flow fan is required to rotate at a speed of 500 r / min to achieve a temperature difference of less than 3°C in each area of ​​the furnace.