A method for preparing a double-zero foil blank and a double-zero foil blank

Abstract

The application provides a preparation method of double-zero foil blank and the double-zero foil blank and belongs to the technical field of aluminum foil manufacturing. The preparation method comprises the following steps: step S1, electrolytic aluminum ingot is heated and melted, Al-50Fe and Al-10Mg are added, cooling is performed, Al-2Y and Al-2Sc are further added, after uniform stirring, core-shell structure alloy particles are added and continuous stirring is performed, finally, Al-5Ti-1B refiner is added, ultrasonic treatment is performed, Ar is introduced, filtration is performed, and aluminum liquid is obtained; step S2, the aluminum liquid is injected into a double-roller casting and rolling device to perform continuous casting and rolling, cooling is performed, and a rough blank is obtained; the rough blank is subjected to soaking treatment, then is subjected to segmented rolling, plasma annealing is performed, cooling is performed, and an intermediate blank is obtained; step S3, the intermediate blank is subjected to cold rolling in 0°, 45° and 90° directions respectively, then is subjected to annealing, cooling is performed, and the double-zero foil blank is obtained. The application can achieve the purposes of balancing the plasticity and strength of the double-zero foil blank, preventing the double-zero foil blank from being broken and improving the surface quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aluminum foil manufacturing, in particular to a preparation method of double-zero foil blank and double-zero foil blank. BACKGROUND

[0002] In the aluminum processing industry, double-zero aluminum foil is widely used in food packaging, medicine packaging, capacitors, tobacco packaging and other fields. Double-zero refers to a thickness usually less than 0.01mm, with extremely high thinness and excellent flexibility. Currently, in the industry, foil blank is usually prepared by hot rolling plus cold rolling, supplemented by a small amount of element (such as Fe, Si) ratio optimization to adjust the mechanical properties. However, this method has several technical bottlenecks. On the one hand, the traditional hot-rolled blank has a coarse primary crystal, and the work hardening rate is low, which is easy to produce fatigue cracks in multi-pass rolling; on the other hand, there is a lack of effective means to control the recrystallization behavior, resulting in unstable structure of the blank after medium annealing, affecting the strength and surface quality of the thin foil product, and limiting the comprehensive performance and line stability of the final foil.

[0003] The patent application file with publication number CN113305149A discloses a manufacturing method of double-zero aluminum foil blank one-time intermediate annealing, relating to the technical field of aluminum alloy foil processing. The chemical composition and mass percentage of aluminum alloy are as follows: Si 0.15-0.30%, Fe 0.70-0.90%, Cu≤0.05%, Mn≤0.03%, Mg≤0.03%, Cr≤0.02%, Zn≤0.10%, Ti 0.02-0.04%, and Al is the remainder. The finished product is made through the steps of melting, casting and rolling, cold rolling, intermediate annealing, edge cutting, secondary cold rolling, secondary edge cutting, foil rolling, slitting, and product annealing. Although the method shortens the production cycle of aluminum foil and improves production efficiency, the mechanical properties and surface quality of the aluminum foil blank prepared by the method are still insufficient.

[0004] Therefore, it is necessary to provide a preparation method of double-zero foil blank and double-zero foil blank to solve the problems existing in the prior art. SUMMARY

[0005] Therefore, the present application provides a preparation method of double-zero foil blank and double-zero foil blank, which can achieve balanced plasticity and strength of double-zero foil blank, is not easy to break and improves the surface quality.

[0006] To achieve the above-mentioned purpose, the present application provides a preparation method of double-zero foil blank, comprising the following steps:

[0007] Step S1, heat and melt the electrolytic aluminum ingot, add Al-50Fe and Al-10Mg, cool down, then add Al-2Y and Al-2Sc, after stirring uniformly, add the core-shell structure alloy particles and continue to stir, finally add Al-5Ti-1B refiner, ultrasonic treatment, Ar is introduced, filtration, to obtain the aluminum liquid;

[0008] Step S2, the aluminum liquid is injected into a double-roller casting and rolling device for continuous casting and rolling, and the rough billet is obtained after cooling; the rough billet is subjected to soaking treatment, then is subjected to segmented rolling, plasma annealing, and cooling to obtain the intermediate billet.

[0009] Step S3, the intermediate billet is subjected to cold rolling in 0°, 45° and 90° directions respectively, then is subjected to annealing and cooling to obtain the double-zero foil billet.

[0010] After the aluminum ingot is completely melted, the aluminum-iron alloy and the aluminum-magnesium alloy are added, so that Fe and Mg are dispersed in the aluminum melt, the Mg atoms are in solid solution in α-Al and produce solute drag effect on dislocations and grain boundaries, thereby improving the deformation resistance and promoting the improvement of rolling plasticity; Fe can form fine and dense dispersions, which can pin the mother phase grain boundaries through pinning effect during solidification and deformation, thereby inhibiting the growth of coarse grains and reducing pinholes. Al-2Y and Al-2Sc are added, Y has strong oxygen affinity and can react with impurities in the melt to form high-melting-point compounds, which, in cooperation with ultrasonic degassing and ceramic filtration, help to deeply purify the melt, thereby reducing inclusions and improving the cleanliness of the aluminum melt; Al3Y and Al3Sc can also be generated, Al3Y has low coarsening rate and strong thermal stability, can continuously play the pinning effect and refine the grains; Al3Sc can provide pinning effect and nucleation promotion, while inhibiting recrystallization and coarsening, and also helps to improve the strength and thermal stability of the billet and make the billet maintain good plasticity.

[0011] Al-5Ti-1B refiner is used for refining in cooperation with ultrasonic treatment. The TiB2 particles in Al-5Ti-1B are insoluble heterogeneous nucleation substrates, which, after entering the melt, preferentially dissolve Al3Ti to provide Ti to the surface of TiB2, thereby improving the crystallographic matching and wettability with α-Al; ultrasonic treatment makes the cavitation bubbles in the liquid metal gather and collapse, generates micro-jets and high-temperature and high-pressure micro-zones, which can further scatter the oxide film and inclusions, promote the local rapid mixing of supersaturated alloy elements, significantly improve the density of primary crystal nuclei, and form fine equiaxed crystals to reduce the holes and surface defects of the billet.

[0012] The plasma annealing method is used, the plasma contains a large number of high-energy electrons, ions and active free radicals, which activate the surface atoms of the billet by bombarding the high-density point defects and dislocations on the surface of the billet, thereby improving the surface quality of the billet; at the same time, the trace oxide layer and organic contaminants on the surface of the billet can also be removed to obtain an ultra-clean surface and improve the subsequent billet forming.

[0013] Multi-directional rolling (0°, 45°, 90°) applies deformation in different directions, forces the grains to experience the start and rotation of different slip systems, disrupts the strong texture formed in a single direction, makes the grain orientation more randomly distributed in space, can significantly weaken the texture strength, reduce the anisotropy of mechanical properties, improve the deep drawing performance and transverse plasticity of the blank, and greatly reduce the risk of cracking and strip breaking caused by anisotropy during subsequent rolling of double zero foil.

[0014] Preferably, in the step S1, the temperature of heating and melting is 740-760℃; and the stirring uniformity time is 5-10min.

[0015] Preferably, in the step S1, the Ar flow rate is 6-10L / min.

[0016] Preferably, the molten aluminum includes the following raw materials in parts by weight:

[0017] 100 parts of electrolytic aluminum ingot, 1.4-1.8 parts of Al-50Fe, 3-5 parts of Al-10Mg, 1-1.5 parts of Al-2Y, 0.5-0.75 parts of Al-2Sc, 0.2-0.4 parts of core-shell structure alloy particles, and 0.32-0.43 parts of Al-5Ti-1B.

[0018] Preferably, the preparation of the core-shell structure alloy particles includes the following steps:

[0019] Under Ar atmosphere, the electrolytic aluminum is heated to complete melting, Al-2Sc and Al-10Hf are sequentially added and stirred, then the melt is poured on a water-cooled copper plate to obtain a rapidly cooled sheet, the sheet is then heated and contacted with Al-5Er to diffuse and form a shell layer, and after cooling, it is cut into 0.5-0.8mm particles and dried to obtain the core-shell structure alloy particles.

[0020] By preparing the core-shell structure alloy particles, Al-2Sc and Al-10Hf as the core structure can preferentially produce L12 type dispersoids Al3(Sc,Hf), which is highly coherent with the matrix α-Al lattice and has a strong effect of pinning dislocations and grain boundaries, and Al-5Er can form a rich Er shell layer Al3Er by epitaxial deposition at the interface between the dispersoids and the matrix, thereby constructing a diffusion barrier outside the core and further inhibiting grain coarsening, thereby reducing the surface Ra and pinhole density and improving the surface quality of the blank.

[0021] Directly adding Al-2Sc, Al-10Hf and Al-5Er can cause them to nucleate simultaneously during casting and soaking, and when the nucleation density is too high for a short time, it can cause uneven distribution and increase defects; and the nucleation and growth speed is relatively fast, which can also easily cause coarsening, reduce the pinning effect, and further reduce the surface quality of the blank and cause strip breaking.

[0022] Preferably, in the step S2, the rough blank is subjected to the heat soaking treatment while a pulse magnetic field is applied, the pulse frequency is 8-12 Hz, and the magnetic field intensity is 0.8-1.2 T.

[0023] The magnetic field can induce micro-current and electromagnetic stirring in the metal liquid, can enhance the diffusion coefficient of Sc, Y, Hf and Er and other elements, can promote the uniform distribution of the elements, can form a perturbation to the solute / vacancy migration and dislocation movement, and can help the fine and uniform recrystallization nucleation; and in the process of dispersoid precipitation, the nucleation density can be improved and the coarsening can be inhibited, and in combination with the heat soaking treatment, finer and more uniform grains and higher dispersoid number density can be achieved, so that the ear height and the pinhole rate are reduced.

[0024] Preferably, in the step S2, the step-by-step rolling comprises the following steps:

[0025] In the first step, asynchronous warm rolling is adopted, the upper roller temperature is 200℃, the lower roller temperature is 100℃, and the rough blank is rolled to 3.6mm; in the second step, cold rolling is adopted, and the blank is rolled to 0.8mm in 0°, 45° and 90° directions.

[0026] The upper roller temperature is significantly higher than the lower roller temperature, so that the deformation resistance of the upper and lower layers of the blank is different (the high-temperature side is soft, and the low-temperature side is hard) and the deformation rate is different. This introduces strong additional shear strain between the upper and lower surfaces, promotes the cross-slip and uniform proliferation of dislocations, refines the grain / subgrain structure; improves the deformation uniformity in the thickness direction of the plate, reduces the residual stress; and helps to improve the uniformity of the strength and plasticity of the blank, and lays a better organizational foundation for subsequent cold rolling.

[0027] Preferably, in the step S2, the pressure of the plasma treatment in the plasma annealing is 50 Pa, the power is 350 W, the temperature is 350-450℃, and the time is 3-5 min.

[0028] Preferably, in the step S3, after the cold rolling is completed, the thickness of the blank is 0.22-0.35mm; the annealing temperature is 280-320℃, and the time is 1-1.5h.

[0029] The final annealing mainly performs a recovery process, a large number of dislocations on the surface of the blank form low-energy subgrain structures through rearrangement or annihilation, which can effectively eliminate internal stress and restore the plasticity of the blank, so as to facilitate the subsequent rolling of the double-zero foil; at the same time, the grain coarsening and strength loss can be avoided to the greatest extent, and the effects of fine-grain strengthening and dispersion strengthening can be maintained.

[0030] In order to achieve the above purpose, the application also provides a double-zero foil blank prepared by the preparation method of the double-zero foil blank.

[0031] The double-zero foil blank prepared by the preparation method can realize balanced plasticity and strength of the double-zero foil blank, is not prone to breakage, and improves surface quality.

[0032] The above technical solutions of the present application at least include the following beneficial effects:

[0033] 1. By adding Al-2Y and Al-2Sc into the aluminum liquid, Al3Y and Al3Sc can be generated to play a pinning effect, inhibit abnormal recrystallization, refine grains, improve the strength and plasticity of the blank, and significantly improve the thermal stability of the blank.

[0034] 2. Al-5Ti-1B refiner is used in combination with ultrasonic treatment for refinement. The Al-5Ti-1B refiner can improve the crystallographic matching and wettability with alpha-Al after melting; ultrasonic treatment promotes the generation of micro-jet and high-temperature and high-pressure micro area, thereby dispersing the oxide film and inclusions, promoting the local rapid mixing of supersaturated alloy elements, significantly increasing the primary crystal nucleus density, forming fine equiaxed crystals, and reducing the blank hole and surface defects.

[0035] 3. The multi-directional rolling method is used to apply deformation in different directions, disrupt the strong texture formed by the grains in a single direction, make the grain orientation more randomly distributed in space, significantly weaken the texture strength, reduce the anisotropy of mechanical properties, and greatly reduce the risk of cracking and strip breaking during subsequent rolling of the double-zero foil due to anisotropy. DETAILED DESCRIPTION

[0036] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be described clearly and completely below in combination with the embodiments of the present application. The described embodiments are part of the embodiments of the present application, and all other embodiments obtained by those skilled in the art based on the described embodiments of the present application belong to the scope of protection of the present application.

[0037] Embodiment 1

[0038] Under an argon atmosphere, 10 g of electrolytic aluminum is heated to 750 DEG C and completely melted, 1.4 g of Al-2Sc and 0.07 g of Al-10Hf are sequentially added, and after stirring for 5 min, the melt is poured on a water-cooled copper plate to obtain a 1-2 mm thick chilled sheet. The sheet is placed at 550 DEG C and contacted with 2.9 g of Al-5Er for diffusion, and after heat preservation for 25 min, a shell layer is formed. After cooling, the shell layer is cut into 0.5 mm particles, and the particles are dried at 120 DEG C for 2 h to obtain core-shell structure alloy particles.

[0039] Put 100 g of electrolytic aluminum ingot into the furnace and heat to 750℃, completely melt, then add 1.6 g of Al-50Fe and 4 g of Al-10Mg in turn, then cool to 720℃, add 1 g of Al-2Y and 0.75 g of Al-2Sc, stir at a speed of 150 rpm for 8 min, add 0.3 g of core-shell structure alloy particles preheated at 400℃ for 10 min and continue to stir for 90 s, then add 0.38 g of Al-5Ti-1B refiner, ultrasonic treatment at a frequency of 20 kHz and a power of 600 W for 10 min, pass Ar gas, Ar flow rate is 8 L / min, continue to pass for 15 min, then stand for 5 min, filter with a 30 μm ceramic filter plate, and obtain the aluminum liquid.

[0040] Pour the aluminum liquid into a double-roller casting and rolling device to perform continuous casting and rolling, the casting and rolling inlet temperature is 710℃, the outlet temperature is 690℃, the casting and rolling speed is 2 m / min; the roller surface temperature is 200℃; the casted blank thickness is 5.8-6.2 mm, after the casting and rolling is completed, use a closed spray water cooling system for rapid cooling, the cooling water temperature is 18-25℃, and obtain the rough blank.

[0041] Homogenize the rough blank, at the same time, apply a pulsed magnetic field of 1.0 T / 10 Hz, heat to 520℃ at a rate of 50℃ / min, keep for 40 min, then reduce to 470℃, keep for 3 h, after the keeping is completed, air cool rapidly, perform staged rolling, the lubricant is selected to be industrial emulsion with a viscosity of 15-25 cP and 0.1% boron nitride nanosheets, the first stage is asynchronous warm rolling, the upper roller temperature is 200℃ and the lower roller temperature is 100℃, cold roll the blank to 3.6 mm; the second stage is cold rolling, roll the blank to 2.4 mm in the 0° direction, roll the blank to 1.2 mm in the 45° direction, and roll the blank to 0.8 mm in the 90° direction, transfer to a plasma annealing furnace, in a vacuum environment, fill in H2 / Ar, the volume ratio of H2 and Ar is 1:1, perform plasma treatment, the pressure is 50 Pa, the power is 350 W, the temperature is set to 400℃, and the treatment time is 4 min, after the annealing is completed, air cool in an inert atmosphere, and obtain the intermediate blank.

[0042] Cold roll the intermediate blank again, roll the blank to 0.6 mm in the 0° direction, roll the blank to 0.4 mm in the 45° direction, and roll the blank to 0.22-0.35 mm in the 90° direction, anneal the blank again, put the blank into an annealing furnace, the temperature is 280℃, the time is 1.5 h, and naturally cool, and obtain the double-zero foil blank.

[0043] Example 2

[0044] Under Ar atmosphere, 10 g of electrolytic aluminum was heated to 750 °C and completely melted, 1.4 g of Al-2Sc and 0.07 g of Al-10Hf were added in sequence, after stirring for 5 min, the melt was poured on a water-cooled copper plate to obtain a 1-2 mm thick rapidly cooled sheet, the sheet was placed at 550 °C and contacted with 2.9 g of Al-5Er for diffusion, and heat preservation was carried out for 25 min to form a shell layer, after cooling, it was cut into 0.5 mm particles, and dried at 120 °C for 2 h to obtain core-shell structure alloy particles.

[0045] 100 g of electrolytic aluminum ingot was put into a furnace and heated to 760 °C and completely melted, then 1.4 g of Al-50Fe and 3 g of Al-10Mg were added in sequence, then the temperature was lowered to 720 °C, 1.5 g of Al-2Y and 0.75 g of Al-2Sc were added, stirred at a speed of 200 rpm for 5 min, 0.2 g of core-shell structure alloy particles preheated at 400 °C for 10 min were added and continuously stirred for 90 s, then 0.43 g of Al-5Ti-1B refiner was added, ultrasonic treatment was carried out at a frequency of 20 kHz and a power of 600 W for 10 min, Ar gas was introduced, the Ar flow rate was 7 L / min, and after continuous introduction for 15 min, it was placed for 5 min, and then filtered using a 30 μm ceramic filter to obtain an aluminum liquid.

[0046] The aluminum liquid was poured into a double-roller casting and rolling device for continuous casting and rolling, the casting and rolling inlet temperature was 710 °C, the outlet temperature was 690 °C, the casting and rolling speed was 1.9 m / min, the roller surface temperature was 190 °C, and the cast blank thickness was 5.8-6.2 mm, after the casting and rolling was completed, a closed spray water cooling system was used for rapid cooling, the cooling water temperature was 18-25 °C, and a rough blank was obtained.

[0047] The rough blank was subjected to soaking treatment, and a pulsed magnetic field of 1.1 T / 12 Hz was applied, the temperature was raised to 520 °C at a rate of 50 °C / min, and heat preservation was carried out for 40 min, then it was lowered to 470 °C and heat preservation was carried out for 3 h, after the heat preservation was completed, it was rapidly air cooled, and was subjected to staged rolling, the lubricant was industrial emulsion with a viscosity of 15-25 cP and 0.1% boron nitride nanosheets, the first stage was asynchronous warm rolling, the upper roller temperature was 200 °C and the lower roller temperature was 100 °C, and the blank was cold rolled to 3.6 mm, the second stage was cold rolling, and the blank was rolled to 2.4 mm in the 0° direction, the blank was rolled to 1.2 mm in the 45° direction, and the blank was rolled to 0.8 mm in the 90° direction, then it was transferred to a plasma annealing furnace, H2 / Ar was filled in a vacuum environment, the volume ratio of H2 and Ar was 1:1, plasma treatment was carried out at a pressure of 50 Pa, a power of 350 W, a temperature of 350 °C, and a treatment time of 5 min, after the annealing was completed, air cooling was carried out in an inert atmosphere, and an intermediate blank was obtained.

[0048] The intermediate blank is cold-rolled again, 0° direction rolling is performed to roll the blank to 0.6 mm; 45° direction rolling is performed to roll the blank to 0.4 mm, 90° direction rolling is performed to roll the blank to 0.22-0.35 mm, the blank is reannealed, the blank is loaded into an annealing furnace, the temperature is 320℃, the time is 1h, and natural cooling is performed to obtain a double-zero foil blank.

[0049] Example 3

[0050] 10g electrolytic aluminum is heated to 750℃ under an argon atmosphere, completely melted, 1.4g Al-2Sc and 0.07g Al-10Hf are sequentially added, after stirring for 5min, the melt is poured on a water-cooled copper plate to obtain a 1-2mm thick rapidly cooled sheet, the sheet is placed at 550℃ and contacted with 2.9g Al-5Er for diffusion, heat preservation is performed for 25min to form a shell layer, after cooling, the sheet is cut into 0.6mm particles, and the particles are dried at 120℃ for 2h to obtain core-shell structure alloy particles.

[0051] 100g electrolytic aluminum ingot is put into a furnace and heated to 740℃, completely melted, 1.8g Al-50Fe and 5g Al-10Mg are sequentially added, then the temperature is lowered to 720℃, 1g Al-2Y and 0.5g Al-2Sc are added, stirring is performed at a speed of 100rpm for 10min, 0.4g core-shell structure alloy particles preheated at 400℃ for 10min are added and the stirring is continued for 90s, 0.32g Al-5Ti-1B refiner is added, ultrasonic treatment is performed at a frequency of 20kHz and a power of 600W for 10min, Ar gas is introduced, the Ar flow rate is 9L / min, the Ar gas is continuously introduced for 15min, then the system is left to stand for 5min, a 30μm ceramic filter plate is used for filtration to obtain an aluminum liquid.

[0052] The aluminum liquid is poured into a double-roller casting and rolling device for continuous casting and rolling, the casting and rolling inlet temperature is 710℃, the outlet temperature is 690℃, the casting and rolling speed is 2.1m / min, the roller surface temperature is 200℃, the cast blank thickness is 5.8-6.2mm, after the casting and rolling is completed, a closed spray water cooling system is used for rapid cooling, the cooling water temperature is 18-25℃, and a rough blank is obtained.

[0053] The rough blank is subjected to soaking treatment while applying a pulsed magnetic field of 0.9T / 9Hz, and is heated to 520°C at a rate of 50°C / min, and is kept for 40min, and then is lowered to 470°C, and is kept for 3h, and after the end of the keeping, is rapidly air-cooled, and is subjected to step rolling, and the lubricant is selected to be industrial emulsion with a viscosity of 15-25cP and 0.1% boron nitride nanosheets, the first step is asynchronous warm rolling, the upper roller temperature is 200°C, and the lower roller temperature is 100°C, and the blank is cold-rolled to 3.6mm; the second step is cold rolling, and is rolled in the 0° direction, and the blank is rolled to 2.4mm; is rolled in the 45° direction, and the blank is rolled to 1.2mm, is rolled in the 90° direction, and the blank is rolled to 0.8mm, and is transferred to a plasma annealing furnace, and is subjected to plasma treatment in a vacuum environment, and H2 / Ar is filled, and the volume ratio of H2 and Ar is 1:1, and the pressure is 50Pa, and the power is 350W, and the temperature is set to 400°C, and the treatment time is 4min, and after the end of the annealing, is air-cooled in an inert atmosphere, and an intermediate blank is obtained.

[0054] The intermediate blank is cold-rolled again, and is rolled in the 0° direction, and the blank is rolled to 0.6mm; is rolled in the 45° direction, and the blank is rolled to 0.4mm, is rolled in the 90° direction, and the blank is rolled to 0.22-0.35mm, and is annealed again, and the blank is loaded into an annealing furnace, and the temperature is 300°C, and the time is 1.5h, and is naturally cooled, and a double-zero foil blank is obtained.

[0055] Example 4

[0056] 10g electrolytic aluminum is heated to 750°C under an Ar atmosphere, completely melted, and 1.4g Al-2Sc and 0.07g Al-10Hf are sequentially added, and after stirring for 5min, the melt is poured on a water-cooled copper plate to obtain a 1-2mm thick rapidly cooled sheet, and the sheet is placed at 550°C and contacted with 2.9g Al-5Er for diffusion, and is kept for 25min to form a shell layer, and after cooling, is cut into 0.8mm particles, and is dried at 120°C for 2h to obtain core-shell structure alloy particles.

[0057] 100g electrolytic aluminum ingot is put into a furnace and heated to 750°C, completely melted, and then 1.6g Al-50Fe and 5g Al-10Mg are sequentially added, and then is lowered to 720°C, and 1g Al-2Y and 0.6g Al-2Sc are added, and stirred at a speed of 150rpm for 8min, and 0.25g core-shell structure alloy particles preheated at 400°C for 10min are added and continuously stirred for 90s, and 0.4g Al-5Ti-1B refiner is added, and is ultrasonically treated at a frequency of 20kHz and a power of 600W for 10min, and Ar gas is introduced, and the Ar flow rate is 6L / min, and is continuously introduced for 15min, and is then left to stand for 5min, and is filtered using a 30μm ceramic filter plate to obtain an aluminum liquid.

[0058] The molten aluminum is injected into a twin roll casting device for continuous casting, with a casting inlet temperature of 710°C, an outlet temperature of 690°C, a casting speed of 1.9 m / min, and a roll surface temperature of 195°C. The cast billet thickness is 5.8-6.2 mm. After casting, a closed spray water cooling system is used for rapid cooling, with a cooling water temperature of 18-25°C, to obtain a rough billet.

[0059] The rough billet is subjected to soaking treatment, with a 1.2 T / 12 Hz pulsed magnetic field applied, and heated to 520°C at a rate of 50°C / min, held for 40 min, then lowered to 470°C and held for 3 h. After soaking, rapid air cooling is performed, and the billet is subjected to stepwise rolling. The lubricant used is an industrial emulsion with a viscosity of 15-25 cP and 0.1% boron nitride nanosheets. The first step is asynchronous warm rolling, with an upper roll temperature of 200°C and a lower roll temperature of 100°C, to cold roll the billet to 3.6 mm. The second step is cold rolling, with 0° rolling to roll the billet to 2.4 mm, 45° rolling to roll the billet to 1.2 mm, and 90° rolling to roll the billet to 0.8 mm. The billet is then transferred to a plasma annealing furnace, and subjected to plasma treatment in a vacuum environment with H2 / Ar at a volume ratio of 1:1, a pressure of 50 Pa, a power of 350 W, and a temperature of 450°C for 3 min. After annealing, air cooling is performed in an inert atmosphere to obtain an intermediate billet.

[0060] The intermediate billet is again cold rolled, with 0° rolling to roll the billet to 0.6 mm, 45° rolling to roll the billet to 0.4 mm, and 90° rolling to roll the billet to 0.22-0.35 mm. The billet is then annealed again by loading it into an annealing furnace at a temperature of 320°C for 1 h, and naturally cooling to obtain a double-zero foil billet.

[0061] Example 5

[0062] Under an Ar atmosphere, 10 g of electrolytic aluminum is heated to 750°C and completely melted. Then 1.4 g of Al-2Sc and 0.07 g of Al-10Hf are added in sequence, and stirred for 5 min. The melt is then poured onto a water-cooled copper plate to obtain a 1-2 mm thick rapidly cooled sheet. The sheet is placed at 550°C and contacted with 2.9 g of Al-5Er for 25 min to form a shell layer. After cooling, the sheet is cut into 0.7 mm particles and dried at 120°C for 2 h to obtain core-shell structure alloy particles.

[0063] Put 100 g of electrolytic aluminum ingot into the furnace and heat to 740℃, completely melt, then add 1.8 g of Al-50Fe and 4 g of Al-10Mg in turn, then cool to 720℃, add 1.5 g of Al-2Y and 0.5 g of Al-2Sc, stir at a speed of 200 rpm for 5 min, add 0.35 g of core-shell structure alloy particles preheated at 400℃ for 10 min and continue to stir for 90 s, then add 0.43 g of Al-5Ti-1B refiner, ultrasonic treatment at a frequency of 20 kHz and a power of 600 W for 10 min, pass Ar gas, Ar flow rate is 10 L / min, continue to pass for 15 min, then stand for 5 min, filter with a 30 μm ceramic filter plate to obtain the aluminum liquid.

[0064] Pour the aluminum liquid into a double-roller casting and rolling device to perform continuous casting and rolling, the casting and rolling inlet temperature is 710℃, the outlet temperature is 690℃, the casting and rolling speed is 2 m / min; the roller surface temperature is 200℃; the casted blank thickness is 5.8-6.2 mm, after the casting and rolling is completed, use a closed spray water cooling system for rapid cooling, the cooling water temperature is 18-25℃, to obtain a rough blank.

[0065] Homogenize the rough blank, at the same time, apply a pulsed magnetic field of 0.8T / 8Hz, heat to 520℃ at a rate of 50℃ / min, keep for 40 min, then reduce to 470℃, keep for 3 h, after the keeping is completed, air cool quickly, perform staged rolling, the lubricant is selected to be industrial emulsion with a viscosity of 15-25 cP and 0.1% boron nitride nanosheets, the first stage is asynchronous warm rolling, the upper roller temperature is 200℃, the lower roller temperature is 100℃, cold roll the blank to 3.6 mm; the second stage is cold rolling, roll the blank to 2.4 mm in the 0° direction, roll the blank to 1.2 mm in the 45° direction, roll the blank to 0.8 mm in the 90° direction, transfer to a plasma annealing furnace, in a vacuum environment, fill in H2 / Ar, the volume ratio of H2 and Ar is 1:1, perform plasma treatment, the pressure is 50 Pa, the power is 350 W, the temperature is set to 350℃, the treatment time is 5 min, after the annealing is completed, air cool in an inert atmosphere to obtain an intermediate blank.

[0066] Cold roll the intermediate blank again, roll the blank to 0.6 mm in the 0° direction, roll the blank to 0.4 mm in the 45° direction, roll the blank to 0.22-0.35 mm in the 90° direction, anneal again, put the blank into an annealing furnace, the temperature is 300℃, the time is 1.2 h, naturally cool to obtain a double-zero foil blank.

[0067] Example 6

[0068] Under Ar atmosphere, 10 g of electrolytic aluminum was heated to 750 °C and completely melted, 1.4 g of Al-2Sc and 0.07 g of Al-10Hf were added in sequence, after stirring for 5 min, the melt was poured on a water-cooled copper plate to obtain a 1-2 mm thick rapidly cooled sheet, the sheet was placed at 550 °C and contacted with 2.9 g of Al-5Er for diffusion, and was kept for 25 min to form a shell layer, after cooling, it was cut into 1 mm particles, and was dried at 120 °C for 2 h to obtain core-shell structure alloy particles.

[0069] 100 g of electrolytic aluminum ingot was put into a furnace and heated to 750 °C and completely melted, then 1.5 g of Al-50Fe and 4.5 g of Al-10Mg were added in sequence, then the temperature was lowered to 720 °C, 1 g of Al-2Y and 0.5 g of Al-2Sc were added, stirred at a speed of 200 rpm for 5 min, 0.3 g of core-shell structure alloy particles preheated at 400 °C for 10 min was added and continuously stirred for 90 s, then 0.4 g of Al-5Ti-1B refiner was added, ultrasonic treated at a frequency of 20 kHz and a power of 600 W for 10 min, Ar gas was introduced at a flow rate of 8 L / min, and the Ar flow was continued for 15 min, then it was placed for 5 min, filtered with a 30 μm ceramic filter plate to obtain an aluminum liquid.

[0070] The aluminum liquid was poured into a double-roller casting and rolling device for continuous casting and rolling, the casting and rolling inlet temperature was 710 °C, the outlet temperature was 690 °C, the casting and rolling speed was 2.1 m / min, the roller surface temperature was 195 °C, and the cast blank thickness was 5.8-6.2 mm, after the casting and rolling was completed, a closed spray water cooling system was used for rapid cooling, the cooling water temperature was 18-25 °C, and a rough blank was obtained.

[0071] The rough blank was subjected to soaking treatment, and a pulsed magnetic field of 1.0 T / 10 Hz was applied, the temperature was raised to 520 °C at a rate of 50 °C / min, and was kept for 40 min, then it was lowered to 470 °C and kept for 3 h, after the soaking was completed, it was rapidly air cooled, and was subjected to staged rolling, the lubricant was industrial emulsion with a viscosity of 15-25 cP and 0.1% boron nitride nanosheets, the first stage was asynchronous warm rolling, the upper roller temperature was 200 °C and the lower roller temperature was 100 °C, and the blank was cold rolled to 3.6 mm, the second stage was cold rolling, and the blank was rolled to 2.4 mm in the 0° direction, the blank was rolled to 1.2 mm in the 45° direction, and the blank was rolled to 0.8 mm in the 90° direction, then it was transferred to a plasma annealing furnace, and was subjected to plasma treatment in a vacuum environment, H2 / Ar was filled, the volume ratio of H2 and Ar was 1:1, the pressure was 50 Pa, the power was 350 W, the temperature was set to 400 °C, and the treatment time was 5 min, after the annealing was completed, it was air cooled in an inert atmosphere to obtain an intermediate blank.

[0072] The intermediate blank is cold-rolled again, 0° direction rolling is performed to roll the blank to 0.6 mm; 45° direction rolling is performed to roll the blank to 0.4 mm, 90° direction rolling is performed to roll the blank to 0.22-0.35 mm, the blank is reannealed, the blank is loaded into an annealing furnace, the temperature is 280℃, the time is 1.5 h, and natural cooling is performed to obtain a double-zero foil blank.

[0073] Example 7

[0074] 10 g of electrolytic aluminum is heated to 750℃ under an argon atmosphere, completely melted, and 1.4 g of Al-2Sc and 0.07 g of Al-10Hf are sequentially added. After stirring for 5 min, the melt is poured onto a water-cooled copper plate to obtain a 1-2 mm thick rapidly cooled sheet. The sheet is placed at 550℃ and contacted with 2.9 g of Al-5Er for diffusion, and a shell layer is formed after 25 min of heat preservation. After cooling, the sheet is cut into 0.8 mm particles, and the particles are dried at 120℃ for 2 h to obtain core-shell structure alloy particles.

[0075] 100 g of electrolytic aluminum ingot is placed in a furnace and heated to 750℃, completely melted, and then 1.5 g of Al-50Fe and 4.5 g of Al-10Mg are sequentially added. After cooling to 720℃, 1 g of Al-2Y and 0.5 g of Al-2Sc are added, and stirring is performed at a speed of 200 rpm for 5 min. 0.3 g of core-shell structure alloy particles preheated at 400℃ for 10 min are added and stirring is continued for 90 s. 0.4 g of Al-5Ti-1B refiner is added, and ultrasonic treatment is performed at a frequency of 20 kHz and a power of 600 W for 10 min. Ar gas is introduced at a flow rate of 8 L / min, and the gas is continuously introduced for 15 min. After 5 min of standing, a 30 μm ceramic filter plate is used to filter the aluminum liquid.

[0076] The aluminum liquid is poured into a double-roller casting and rolling device for continuous casting and rolling. The casting and rolling inlet temperature is 710℃, the outlet temperature is 690℃, the casting and rolling speed is 2.1 m / min, the roller surface temperature is 195℃, and the cast blank thickness is 5.8-6.2 mm. After casting and rolling, a closed spray water cooling system is used for rapid cooling, and the cooling water temperature is 18-25℃. A rough blank is obtained.

[0077] The rough blank is subjected to soaking treatment, is raised to 520 DEG C at a rate of 50 DEG C / min, is kept for 40 min, is then lowered to 470 DEG C, is kept for 3 h, after the keeping treatment, is rapidly air-cooled, is subjected to step rolling, an industrial emulsion with a viscosity of 15-25 cP and 0.1% boron nitride nanosheet are selected as lubricants, the first step is asynchronous warm rolling, the upper roller temperature is 200 DEG C, the lower roller temperature is 100 DEG C, the blank is cold-rolled to 3.6 mm; the second step is cold rolling, 0 DEG direction rolling is carried out, the blank is rolled to 2.4 mm; 45 DEG direction rolling is carried out, the blank is rolled to 1.2 mm, 90 DEG direction rolling is carried out, the blank is rolled to 0.8 mm, is transferred to a plasma annealing furnace, in a vacuum environment, H2 / Ar is filled, the volume ratio of H2 and Ar is 1:1, plasma treatment is carried out, the pressure is 50 Pa, the power is 350 W, the temperature is set to 400 DEG C, the treatment time is 5 min, after the annealing, air cooling is carried out in an inert atmosphere, and the intermediate blank is obtained.

[0078] The intermediate blank is cold-rolled again, 0 DEG direction rolling is carried out, the blank is rolled to 0.6 mm; 45 DEG direction rolling is carried out, the blank is rolled to 0.4 mm, 90 DEG direction rolling is carried out, the blank is rolled to 0.22-0.35 mm, the blank is again annealed, the blank is loaded into an annealing furnace, the temperature is 280 DEG C, the time is 1.5 h, and natural cooling is carried out, and the double zero foil blank is obtained.

[0079] The present application also carries out comparative examples and related tests.

[0080] Comparative Example 1

[0081] Comparative Example 1 and Example 1 only differ in that Al-2Y and Al-2Sc are not added in Comparative Example 1, but Al is used instead, other compositions and preparation methods are the same as those in Example 1, and the double zero foil blank is prepared.

[0082] Comparative Example 2

[0083] Comparative Example 2 and Example 1 differ in that core-shell structure alloy particles are not used in Comparative Example 2, but Al is used instead, other compositions and preparation methods are the same as those in Example 1, and the double zero foil blank is prepared.

[0084] Comparative Example 3

[0085] Comparative Example 3 and Example 1 differ in that multi-directional (0 DEG, 45 DEG, 90 DEG ) rolling is not carried out in Comparative Example 3, other compositions and preparation methods are the same as those in Example 1, and the double zero foil blank is prepared.

[0086] Performance detection test

[0087] According to GB / T 228.1-2021 “Metallic materials-Tensile testing-Part 1: Method of test at room temperature”, the tensile strength and elongation of the double-zero foil blanks prepared in Examples 1-7 and Comparative Examples 1-3 were tested. The samples with a width of 15 mm and a gauge length of 50 mm were taken, and the tensile strength of the samples was tested at a strain rate of 2 mm / min. Then, samples were taken at 0° and 90° along the rolling direction for elongation testing.

[0088] According to GB / T 2523-2019 “Measurement method of surface roughness of cold-rolled metal sheet (strip)”, the surface roughness of the double-zero foil blanks prepared in Examples 1-7 and Comparative Examples 1-3 was tested. The sample length was 0.8 mm, and the arithmetic mean value was taken by measuring 5 random points on the surface of the sample.

[0089] According to GB / T 3198-2020 “Aluminum and aluminum alloy foil”, the number of pinholes of the double-zero foil blanks prepared in Examples 1-7 and Comparative Examples 1-3 was tested by light transmission method.

[0090] The above test results are shown in Table 1.

[0091] Table 1

[0092]

[0093] As can be seen from the results in Table 1, the tensile strength and elongation of the blank prepared in Comparative Example 1 decreased significantly compared with Example 1, indicating that Al-2Y and Al-2Sc can generate Al3Y and Al3Sc, play a pinning effect and refine the grains, and improve the strength and plasticity of the blank. The number of pinholes in Comparative Example 2 increased significantly compared with Example 1, indicating that the core-shell structure alloy particles help to inhibit grain coarsening, thereby reducing pinholes and improving the surface quality of the blank. The elongation of the sample at 90° in the rolling direction of the blank prepared in Comparative Example 3 decreased significantly compared with the blank prepared in Example 1, indicating that multi-directional rolling helps to weaken the texture strength, reduce the anisotropy of mechanical properties, and improve the plasticity of the blank.

[0094] The difference between Example 7 and Example 6 is that the blank prepared in Example 7 was not subjected to a magnetic field during the soaking treatment. Compared with Example 6, the performance test results of the blank prepared in Example 7 all decreased to some extent, indicating that the magnetic field can enhance the diffusion coefficient of Sc, Y, Hf and Er elements, promote the uniform distribution of elements, obtain finer and more uniform grains and higher dispersion body number density, and thus reduce pinholes.

[0095] The above is a preferred embodiment of the present application. Those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered within the scope of protection of the present application.

Claims

1. A method for preparing a double-zero foil blank, characterized in that, Includes the following steps: Step S1: Heat and melt the electrolytic aluminum ingot, add Al-50Fe and Al-10Mg, cool down, then add Al-2Y and Al-2Sc, stir evenly, add core-shell structured alloy particles and continue stirring, finally add Al-5Ti-1B refining agent, sonicate, introduce Ar, filter, and obtain aluminum liquid. Step S2: Inject molten aluminum into a twin-roll casting and rolling mill for continuous casting and rolling, and then cool it to obtain a rough billet; The rough billet is subjected to homogenization heat treatment, followed by segmented rolling, plasma annealing, and cooling to obtain the intermediate billet; Step S3: The intermediate billet is cold rolled at 0°, 45° and 90° respectively, then annealed and cooled to obtain a double zero foil billet; The molten aluminum comprises the following raw materials in parts by weight: 100 parts electrolytic aluminum ingot, 1.4-1.8 parts Al-50Fe, 3-5 parts Al-10Mg, 1-1.5 parts Al-2Y, 0.5-0.75 parts Al-2Sc, 0.2-0.4 parts core-shell alloy particles, and 0.32-0.43 parts Al-5Ti-1B; The preparation of the core-shell structured alloy particles includes the following steps: Under an Ar atmosphere, electrolytic aluminum is heated to complete melting, and Al-2Sc and Al-10Hf are added sequentially and stirred. The melt is then poured onto a water-cooled copper plate to obtain a rapidly cooled thin plate. The thin plate is then heated and diffused with Al-5Er to form a shell. After cooling, it is cut into 0.5-0.8 mm particles, dried, and core-shell structured alloy particles are obtained.

2. The method for preparing a double-zero foil blank according to claim 1, characterized in that, In step S1, the heating and melting temperature is 740-760℃; the stirring time is 5-10 minutes.

3. The method for preparing a double-zero foil blank according to claim 1, characterized in that, In step S1, the Ar flow rate is 6-10 L / min.

4. The method for preparing a double-zero foil blank according to claim 1, characterized in that, In step S2, while the billet is subjected to homogenization heat treatment, a pulsed magnetic field is also applied, with a pulse frequency of 8-12Hz and a magnetic field strength of 0.8-1.2T.

5. The method for preparing a double-zero foil blank according to claim 1, characterized in that, In step S2, the segmented rolling process includes the following steps: The first stage uses asynchronous warm rolling, with the upper roll temperature at 200℃ and the lower roll temperature at 100℃, rolling the rough billet to 3.6mm; the second stage uses cold rolling, which is performed in the 0°, 45° and 90° directions respectively, rolling the billet to 0.8mm.

6. The method for preparing a double-zero foil blank according to claim 1, characterized in that, In step S2, the plasma treatment pressure during plasma annealing is 50 Pa, the power is 350 W, the temperature is 350-450 °C, and the time is 3-5 min.

7. The method for preparing a double-zero foil blank according to claim 1, characterized in that, In step S3, the thickness of the billet after cold rolling is 0.22-0.35 mm; the annealing temperature is 280-320℃ and the time is 1-1.5 h.

8. A double-zero foil blank, characterized in that, It is prepared by the method for preparing a double-zero foil blank according to any one of claims 1-7.

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