A production method of 8021 alloy high elongation double zero aluminum foil

Abstract

The invention discloses a production method of 8021 alloy high-elongation double-zero aluminum foil, belonging to the technical field of aluminum foil preparation. The method includes: rough rolling, intermediate rolling, coiling, tempering, finishing rolling, slitting and annealing. The composition of the rough rolling oil is calculated by mass percentage: ester additive 5.0-5.5%, alcohol additive 1.8-2.2%, lauric acid 0.2-0.4%, 80# base oil balance; the composition of the intermediate rolling oil is calculated by mass percentage: ester additive 5.2-5.8%, alcohol additive 1.5-2.0%, lauric acid 0.15-0.25%, 80# base oil balance; the composition of the finishing rolling oil is calculated by mass percentage: ester additive 5.5-6.0%, alcohol additive 1.2-1.6%, lauric acid ≤0.1%, 80# base oil balance; the tempering temperature is 120-150°C, and the tempering time is 8-12h. The present invention can reduce pinholes caused by aluminum powder.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum foil preparation, and particularly relates to a production method of 8021 alloy high-elongation double-zero aluminum foil. Background Art

[0002] Packaging aluminum foil is a special material widely used in the fields of food, medicine, cosmetics and electronics. Its main features are light weight, corrosion resistance, good thermal conductivity and easy forming. Due to its good performance in strength, elongation and compressibility, 8021 alloy has been gradually developed for the production of double-zero packaging aluminum foil. The existing production method of 8021 alloy double-zero aluminum foil includes the following processes: rough rolling, intermediate rolling, coiling, tempering, finishing rolling, slitting and annealing.

[0003] For example, the patent application number CN201510304101.2 discloses a double zero aluminum foil thickness difference rolling method, including:

[0004] Rough rolling: The cast aluminum foil billet is put into the rough rolling mill and lubricated with rolling oil. The reduction amount of each rough rolling pass is 0.24mm→0.115mm→0.06mm→0.03mm.

[0005] For intermediate rolling, the aluminum coils that have been rough rolled are put into the intermediate rolling mill and lubricated with rolling oil. The reduction of each pass of intermediate rolling is: 0.03mm→0.014mm, 0.03mm→0.0118mm.

[0006] For coil closing, the two thickness aluminum coils after intermediate rolling are trimmed by 10 mm on both sides and overlapped, and the middle is oiled with double-combined oil, to which 5%-15% by mass of lubricating oil is added.

[0007] Intermediate annealing: After the combined coils are rolled, the aluminum coils with specifications of (0.014mm+0.0118mm)*1240mm are subjected to high-temperature annealing. The temperature is raised to 170℃ to 190℃ in the annealing furnace within 2 hours and kept at this temperature for 4 to 8 hours. After 2-3 hours of cooling, the coils are taken out of the furnace.

[0008] Finishing rolling: The aluminum coil that has been intermediate annealed is put into the finishing rolling mill and lubricated with rolling oil. The reduction of each pass of finishing rolling is: 0.0258mm, i.e. 0.014mm+0.0118mm→0.011mm, i.e. 0.006mm+0.005mm.

[0009] Slitting: the obtained aluminum foil is cut into aluminum foil of designed width by a slitting machine.

[0010] The semi-finished products are degreased and annealed. After being cut, the semi-finished products are electrically heated to 200℃-220℃ in an annealing furnace and kept warm for 3-5 hours, then cooled to 175℃-185℃ and kept warm for 3-5 hours, and finally cooled and taken out of the furnace.

[0011] Packaging: The degreased and annealed aluminum foil is packaged in moisture-proof packaging and packed in boxes.

[0012] The additives in the rolling oil are MAS-1 and SET-12.

[0013] For example, the patent application number CN201810171994.1 discloses an aluminum foil rolling process, which includes the following steps:

[0014] S1: In the first rolling, a 280um billet is placed in a rolling mill for rough rolling, and cooling lubricating oil is sprayed on the billet. The thickness of the rolled coil is 107um-112um.

[0015] S2: The second rolling process is to put the coils that have been rolled in the first rolling process into the rolling mill for rough rolling or intermediate rolling. At the same time, the coils that have been rolled in the first rolling process are sprayed with cooling lubricating oil. The thickness of the rolled coils is 41um-44.8um.

[0016] S3: The third rolling pass, the material coil completed by the second rolling pass is placed in the rolling mill for intermediate rolling, and cooling lubricating oil is sprayed on the material coil completed by the second rolling pass. The thickness of the rolled material coil is 15.7um-17.9um.

[0017] S4: Coil closing: two coils that have been rolled in the third pass are placed in a coil closing machine for coil closing, and cooling lubricating oil is sprayed on the two coils that have been rolled in the third pass.

[0018] S5: The fourth rolling process is to put the coil into the rolling mill for finishing rolling. At the same time, the coil is sprayed with cooling lubricating oil. The thickness of the finished product after rolling is 6um-7um.

[0019] The roughness of the rollers in the first and second rolling passes was 0.28 micrometers; the roughness of the rollers in the third rolling pass was 0.15 micrometers; and the roughness of the rollers in the fourth rolling pass was 0.06 micrometers.

[0020] For example, the patent application number CN201310677586.0 discloses a production process of 8021 alloy double zero aluminum foil, which includes the following steps:

[0021] (1) The raw materials are prepared according to the proportions, and then smelted, refined, and hot-rolled to produce hot-rolled billets with a thickness of 3 mm.

[0022] (2) Cold rolling: The 3mm thick hot-rolled billet is rolled, deformed and coiled into a 0.24mm thick cold-rolled billet through a cold rolling mill.

[0023] (3) Recoiling and trimming: The 0.24 mm thick cold rolled billet is passed through a recoiling machine for trimming to obtain a 0.24 mm aluminum foil billet.

[0024] (4) Intermediate rolling: The intermediate rolling mill uses a low roughness roller, low pass reduction, and a high additive content process to produce a 0.24mm thick aluminum foil billet through four passes of 0.24mm-0.125mm-0.064mm-0.03mm-0.014mm to form a 0.014mm thick single zero aluminum foil billet.

[0025] (5) Surface annealing: 0.014 mm thick single-zero aluminum foil is subjected to surface annealing in an annealing furnace at 165°C for 10 hours to soften the surface of the aluminum foil, thereby achieving the purpose of reducing rolling load, refining and reducing pinholes.

[0026] (6) Finishing rolling: The single-piece aluminum foil billet with a thickness of 0.014 mm that has been surface annealed is rolled into two sheets by a finishing mill.

[0027] (7) Slitting: The double-coiled 0.006-0.007mm thick double-zero aluminum foil blank is rolled and sheared by a slitting machine to obtain a single sheet of 0.006-0.007mm thick double-zero aluminum foil.

[0028] (8) Annealing, degreasing and packaging: The above-mentioned single sheet of 0.006-0.007 mm thick 8021 alloy double zero aluminum foil is subjected to annealing furnace for tempering, degreasing and cooling, and then packaged to obtain the finished 8021 alloy double zero aluminum foil.

[0029] The products processed by the existing technology have a large number of pinholes. For example, the number of pinholes in the product obtained by CN201510304101.2 is as high as 1000 / m 2 about. Summary of the invention

[0030] In order to solve the above problems, the embodiment of the present invention provides a production method of 8021 alloy high elongation double zero aluminum foil, which controls the composition and ratio of the lubricating oil used for aluminum foil rolling to ensure the oil film strength and thickness on the surface of the aluminum foil during foil rolling, so that the aluminum powder generated during the rolling process can be adsorbed and taken away by the rolling oil, thereby improving the surface quality of the aluminum foil, reducing the pinholes caused by the aluminum powder, and improving the dense clustering of pinholes in the finished 8021 alloy double zero aluminum foil. The technical solution is as follows:

[0031] The embodiment of the present invention provides a production method of 8021 alloy high elongation double zero aluminum foil, which comprises: rough rolling, intermediate rolling, coiling, tempering, finishing rolling, slitting and annealing in sequence; wherein the composition of the rough rolling oil is calculated by mass percentage: ester additive 5.0-5.5%, alcohol additive 1.8-2.2%, lauric acid 0.2-0.4%, 80# base oil balance; the composition of the intermediate rolling oil is calculated by mass percentage: ester additive 5.2-5.8%, alcohol additive 1.5-2.0%, lauric acid 0.15-0.25%, 80# base oil balance; the composition of the finishing rolling oil is calculated by mass percentage: ester additive 5.5-6.0%, alcohol additive 1.2-1.6%, lauric acid ≤0.1%, 80# base oil balance. wherein the tempering temperature is 120-150°C, and the tempering time is 8-12h.

[0032] Among them, the ester additives and alcohol additives are both commercially available products, the same as in the prior art, and specifically can be STE-12 alcohol and STE-6 ester.

[0033] The present invention controls the composition and ratio of lubricating oil for rolling aluminum foil, thereby ensuring the oil film strength and thickness on the surface of the aluminum foil during foil rolling, so that the aluminum powder generated during the rolling process can be adsorbed and taken away by the rolling oil, thereby improving the surface quality of the aluminum foil, reducing pinholes caused by aluminum powder, and improving the phenomenon of densely clustered pinholes in the 8021 alloy double-zero finished aluminum foil.

[0034] Among them, this patent adopts low-temperature tempering to reduce the residual stress after the rolling deformation process of the aluminum foil and the tensile stress of slitting and coiling, thereby suppressing the problems of coarse grains and rapid hardening, solving the problems of heavy longitudinal stripes on the dark side of the double-zero finished product, low elongation and dense clustering of pinholes, and reducing the number of pinholes.

[0035] The base material for rough rolling is 8021 alloy with a specification of 0.24-0.26mm*1600mm. The element composition of the alloy is as follows by mass percentage: Fe1.2-1.5%, Si≤0.15%, Cu≤0.05%, Mn0.05-0.10%, Ti≤0.05%, and the balance is Al and unavoidable impurities.

[0036] Specifically, the rough rolling is carried out through two rolling passes to roll the substrate with a thickness of 0.24-0.26 mm into a coil with a thickness of 0.040-0.045 mm. The intermediate rolling is carried out to roll the coil with a thickness of 0.040-0.045 mm into a coil with a thickness of 0.0145-0.0155 mm. The finishing rolling is carried out to roll the coiled coil (to obtain a double-layer aluminum foil) into a single-layer aluminum foil with a thickness of 0.0060-0.0065 mm.

[0037] Among them, the roughness of the rough rolling roller is 0.24-0.28μm, and the convexity is 0.03-0.04mm. The roughness of the intermediate rolling roller is 0.12-0.15μm, and the convexity is 0.04-0.05mm. The roughness of the finishing rolling roller is 0.05-0.08μm, and the convexity is 0.05-0.06mm. The present invention controls the roughness of the rough rolling, intermediate rolling and finishing rolling rollers of the foil rolling working rollers and the grinding wheel, so that the roughness of the rollers decreases step by step to form a drop, and cooperates with rolling oil to gradually reduce the amount of aluminum powder falling off the surface of the aluminum foil during the rolling process, thereby improving the phenomenon of heavy longitudinal stripes and densely clustered pinholes on the dark side of the 8021 alloy double-zero finished aluminum foil.

[0038] Furthermore, the grinding wheel for the rough rolling roller is a 180-mesh ceramic grinding wheel; the grinding wheel for the intermediate rolling roller is a 180-mesh resin grinding wheel; the finishing rolling roller is first ground with a 180-mesh ceramic grinding wheel to roughly grind and eliminate the fatigue layer, and then polished with a 320-mesh resin grinding wheel to ensure the surface quality of the roller.

[0039] The coiling process is as follows: 2 sheets of material coils with a thickness of 0.0145-0.0155 mm are doubled together, and the thickness difference of the 2 sheets of aluminum foil is ≤0.0005 mm; the double-coupling speed is 700-800 m / min; the double-coupling oil is sprayed by mist, and the spray pressure of the mist is 0.55-0.65 MPa.

[0040] The tempering process is as follows: the coiled material is sent to a box-type annealing furnace, kept at 120-150°C for 8-12 hours, and air-cooled after being taken out of the furnace.

[0041] Among them, see Figure 2 , the annealing process includes the following steps:

[0042] S801 preheating: send the cut aluminum foil to the box-type annealing furnace and raise the furnace temperature to 60-70℃ at a heating rate of 1-3℃ / h.

[0043] S802 degreasing: Raise the furnace temperature to 170-190℃ at a heating rate of 2-4℃ / h and keep it constant for 45-50h.

[0044] S803 performance improvement: Raise the furnace temperature to 210-230℃ at a heating rate of 4-6℃ / h and keep it constant for 25-30h.

[0045] S804 Cooling: Reduce the furnace temperature to 120-150℃ at a cooling rate of 1-3℃ / min and keep warm for 10-15h.

[0046] S805 Cooling: Reduce the furnace temperature to 60-80℃ at a cooling rate of 2-4℃ / min and keep warm for 10-15h.

[0047] S806 is taken out of the furnace: loosen the furnace door, open a small part of the furnace door (specifically 1 / 5 of the furnace door) after 7-9 hours, half open the furnace door after another 4-6 hours, and then take out of the furnace after another 2-4 hours.

[0048] Among them, the present invention adopts a slow multi-step finished product annealing process and a step-by-step furnace opening method, which can achieve a good degreasing effect on the surface of the aluminum foil, and can suppress the annealing bar problem caused by rapid heating and cooling of the aluminum foil, thereby improving the yield of the aluminum foil.

[0049] Preferably, the composition of the rough rolling oil is calculated by mass percentage: 5.3% ester additives, 2.1% alcohol additives, 0.28% lauric acid, and the balance of 80# base oil. The composition of the medium rolling oil is calculated by mass percentage: 5.6% ester additives, 1.8% alcohol additives, 0.15% lauric acid, and the balance of 80# base oil. The composition of the finishing rolling oil is calculated by mass percentage: 5.8% ester additives, 1.5% alcohol additives, 0.08% lauric acid, and the balance of 80# base oil. The tempering temperature is 130°C and the tempering time is 10h.

[0050] Specifically, see Figure 1 The method for producing 8021 alloy high elongation double zero aluminum foil provided in the embodiment of the present invention comprises the following steps:

[0051] S101 substrate selection: Select 8021 alloy billet with specifications of 0.24-0.26mm*1600mm.

[0052] S102 Rough rolling: The substrate with a thickness of 0.24-0.26mm is rolled twice through a rough rolling mill to obtain a coil with a thickness of 0.040-0.045mm. The composition of the rough rolling oil is calculated by mass percentage: ester additives 5.0-5.5%, alcohol additives 1.8-2.2%, lauric acid 0.2-0.4%, 80# base oil balance; the roughness of the rough rolling roller is 0.24-0.28μm, and the convexity is 0.03-0.04mm.

[0053] S103 intermediate rolling: the coil with a thickness of 0.040-0.045mm is rolled through the intermediate rolling mill to obtain a coil with a thickness of 0.0145-0.0155mm. The composition of the intermediate rolling oil is calculated by mass percentage: ester additive 5.2-5.8%, alcohol additive 1.5-2.0%, lauric acid 0.15-0.25%, 80# base oil balance; the roughness of the intermediate rolling roll is 0.12-0.15μm, and the convexity is 0.04-0.05mm.

[0054] S104 Coiling: The coiling machine double-coils two sheets of aluminum foil with a thickness of 0.0145-0.0155mm. The thickness difference between the two sheets of aluminum foil is ≤0.0005mm, and the double-coiling speed is 700-800m / min. The double-coiling oil is sprayed by mist, and the spray pressure is 0.55-0.65Mpa.

[0055] S105 tempering: The coiled material is sent to the box-type annealing furnace, kept at 120-150℃ for 8-12h, and air-cooled after leaving the furnace.

[0056] S106 Finishing rolling: The finishing rolling mill rolls the coiled material to obtain aluminum foil with a single layer thickness of 0.0060-0.0065mm. The composition of the finishing rolling oil is calculated by mass percentage: ester additives 5.5-6.0%, alcohol additives 1.2-1.6%, lauric acid ≤0.1%, 80# base oil balance; the roughness of the finishing rolling roller is 0.05-0.08μm, and the convexity is 0.05-0.06mm.

[0057] S107 Slitting: Slitting the aluminum foil according to the predetermined size.

[0058] S108 annealing: send the cut aluminum foil to the box annealing furnace, increase the furnace temperature to 60-70℃ at a heating rate of 1-3℃ / h; increase the furnace temperature to 170-190℃ at a heating rate of 2-4℃ / h, and keep it constant for 45-50h; increase the furnace temperature to 210-230℃ at a heating rate of 4-6℃ / h, and keep it constant for 25-30h; reduce the furnace temperature to 120-150℃ at a cooling rate of 1-3℃ / min, and keep it constant for 10-15h; reduce the furnace temperature to 60-80℃ at a cooling rate of 2-4℃ / min, and keep it constant for 10-15h; loosen the furnace door, open 1 / 5 of the furnace door after 7-9h, half open the furnace door after 4-6h, and take it out of the furnace after another 2-4h.

[0059] The present invention has the following advantages: the elongation of the double zero aluminum foil processed by the method provided by the present invention is greater than 3%, and the number of pinholes is less than 200 / m 2 , under optimized conditions, the number of pinholes is less than 100 / m 2 ; No dense clustering of pinholes, no annealing bar phenomenon. Through a special annealing process, the yield of aluminum foil can be improved (up to more than 92%). BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is a flow chart of a method for producing 8021 alloy high elongation double zero aluminum foil provided in an embodiment of the present invention;

[0061] Figure 2 It is a flow chart of the annealing process. DETAILED DESCRIPTION

[0062] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings.

[0063] Example 1

[0064] Example 1 provides a method for producing 8021 alloy high elongation double zero aluminum foil, the specific steps are as follows:

[0065] S101 substrate selection: Select 8021 alloy billet with a specification of 0.24mm*1600mm.

[0066] S102 Rough rolling: The substrate with a thickness of 0.24 mm is rolled twice through a rough rolling mill to obtain a coil with a thickness of 0.040 mm. The composition of the rough rolling oil is as follows by mass percentage: 5.5% ester additives, 2.0% alcohol additives, 0.25% lauric acid, and the balance of 80# base oil; the roughness of the rough rolling roll is 0.25 μm, and the convexity is 0.035 mm.

[0067] S103 intermediate rolling: a coil with a thickness of 0.040 mm is rolled through an intermediate rolling mill to obtain a coil with a thickness of 0.0145 mm. The composition of the intermediate rolling oil is as follows by mass percentage: 5.6% ester additives, 1.8% alcohol additives, 0.15% lauric acid, and the balance of 80# base oil; the roughness of the intermediate rolling roll is 0.13 μm, and the convexity is 0.045 mm.

[0068] S104 Coiling: The coiling machine double-coils two sheets of aluminum foil with a thickness of 0.0145 mm. The thickness difference between the two sheets of aluminum foil is 0.0003 mm, and the double-coiling speed is 700 m / min. The double-coiling oil is sprayed by mist, and the spray pressure is 0.58 MPa.

[0069] S105 tempering: The coiled material (2*0.0145mm) is sent to a box-type annealing furnace, kept at 150℃ for 8h, and air-cooled after being taken out of the furnace.

[0070] S106 Finishing Rolling: The finishing mill rolls the coiled material (2*0.0145mm) to obtain 2*0.0063mm aluminum foil, with a single layer thickness of 0.0063mm. The composition of the finishing rolling oil is calculated by mass percentage: 5.8% ester additives, 1.5% alcohol additives, 0.08% lauric acid content, and 80# base oil balance; the roughness of the finishing rolling roller is 0.07μm and the convexity is 0.05mm.

[0071] S107 Slitting: Slitting the aluminum foil according to a predetermined size to obtain a single sheet of single-sided smooth aluminum foil.

[0072] S108 annealing: send the cut aluminum foil to a box annealing furnace, increase the furnace temperature to 70℃ at a heating rate of 1.5℃ / h; increase the furnace temperature to 180℃ at a heating rate of 2℃ / h, and keep it constant for 45h; increase the furnace temperature to 220℃ at a heating rate of 4.5℃ / h, and keep it constant for 25h; reduce the furnace temperature to 130℃ at a cooling rate of 1.5℃ / min, and keep it constant for 12h; reduce the furnace temperature to 75℃ at a cooling rate of 2.5℃ / min, and keep it constant for 10h; loosen the furnace door, open 1 / 5 of the furnace door after 8h, half open the furnace door after 5h, and take it out of the furnace after another 3h.

[0073] S109 Packaging: Packaging is done after cooling to room temperature.

[0074] The 8021 alloy "O" state 0.0063mm aluminum foil product obtained by the above production has an elongation of 3.02% according to "GB / T228.1 Metal Material Tensile Test-Part 1: Room Temperature Test Method", and a pinhole count of 108 / m according to "GB / T22638.2-2016-Aluminum Foil Test Method-Part 2: Pinhole Detection". 2 , there is no annealing bar phenomenon on the annealed surface of aluminum foil.

[0075] Example 2

[0076] Example 2 provides a method for producing 8021 alloy high elongation double zero aluminum foil, the specific steps are as follows:

[0077] S101 substrate selection: Select 8021 alloy billet with a specification of 0.24mm*1600mm.

[0078] S102 Rough rolling: The substrate with a thickness of 0.24 mm is rolled twice through a rough rolling mill to obtain a coil with a thickness of 0.043 mm. The composition of the rough rolling oil is as follows by mass percentage: 5.3% ester additives, 2.1% alcohol additives, 0.28% lauric acid, and the balance of 80# base oil; the roughness of the rough rolling roll is 0.26μm and the convexity is 0.04mm.

[0079] S103 intermediate rolling: the coil with a thickness of 0.043mm is rolled through the intermediate rolling mill to obtain a coil with a thickness of 0.015mm. The composition of the intermediate rolling oil is as follows by mass percentage: 5.6% ester additives, 1.8% alcohol additives, 0.15% lauric acid, and the balance of 80# base oil; the roughness of the intermediate rolling roll is 0.135μm, and the convexity is 0.04mm.

[0080] S104 Coiling: The coiling machine double-coils two sheets of aluminum foil with a thickness of 0.015 mm. The thickness difference between the two sheets of aluminum foil is 0.0004 mm, and the double-coiling speed is 720 m / min. The double-coiling oil is sprayed by mist, and the spray pressure is 0.6 MPa.

[0081] S105 tempering: The coiled material (2*0.015mm) is sent to a box-type annealing furnace, kept at 130℃ for 10h, and air-cooled after being taken out of the furnace.

[0082] S106 Finishing Rolling: The finishing mill rolls the coiled material (2*0.015mm) to obtain 2*0.0065mm aluminum foil with a single layer thickness of 0.0065mm. The composition of the finishing rolling oil is calculated by mass percentage: 5.8% ester additives, 1.5% alcohol additives, 0.08% lauric acid content, and 80# base oil balance; the roughness of the finishing rolling roller is 0.06μm and the convexity is 0.05mm.

[0083] S107 Slitting: Slitting the aluminum foil according to a predetermined size to obtain a single sheet of single-sided smooth aluminum foil.

[0084] S108 annealing: send the cut aluminum foil to a box annealing furnace, increase the furnace temperature to 70℃ at a heating rate of 1.5℃ / h; increase the furnace temperature to 180℃ at a heating rate of 2℃ / h, and keep it constant for 45h; increase the furnace temperature to 220℃ at a heating rate of 4.5℃ / h, and keep it constant for 25h; reduce the furnace temperature to 130℃ at a cooling rate of 1.5℃ / min, and keep it constant for 12h; reduce the furnace temperature to 75℃ at a cooling rate of 2.5℃ / min, and keep it constant for 10h; loosen the furnace door, open 1 / 5 of the furnace door after 8h, half open the furnace door after 5h, and take it out of the furnace after another 3h.

[0085] S109 Packaging: Packaging is done after cooling to room temperature.

[0086] The 8021 alloy "O" state 0.0065mm aluminum foil product obtained by the above production has an elongation of 3.56% according to "GB / T228.1 Metal Material Tensile Test-Part 1: Room Temperature Test Method", and 95 pinholes / m according to "GB / T22638.2-2016-Aluminum Foil Test Method-Part 2: Pinhole Detection". 2 , there is no annealing bar phenomenon on the annealed surface of aluminum foil.

[0087] Comparative Example 1: The process is basically the same as that of Example 2, except that the tempering conditions are: the tempering temperature is 180° C., and the tempering time is 7 h.

[0088] Comparative Example 2: The process is basically the same as that of Example 2, except that the composition of the finishing oil is, by mass percentage, 2% alcohol additive, 8% lauric acid, and the remainder 80# base oil.

[0089] Comparative Example 3: The process is basically the same as that of Example 2, except that the composition of the finishing oil is, by mass percentage, 5.3% of ester additives, 2.1% of alcohol additives, 0.28% of lauric acid, and the remainder of 80# base oil.

[0090] Comparative Example 4: The process is basically the same as that of Example 2, except that the composition of the finishing oil is, by mass percentage, 1.5% alcohol additive, 0.08% lauric acid content, and the remainder 80# base oil.

[0091] Comparative Example 5: The process is basically the same as that of Example 2, except that the composition of the medium rolling oil is, by mass percentage, 5.3% of ester additives, 2.1% of alcohol additives, 0.28% of lauric acid, and the remainder of 80# base oil.

[0092] Comparative Example 6: The process is basically the same as that of Example 2, except that the rough rolling oil, the intermediate rolling oil and the finishing rolling oil are the same, and their compositions are calculated by mass percentage as follows: 5.3% ester additives, 2.1% alcohol additives, 0.28% lauric acid, and the remainder 80# base oil.

[0093] Comparative Example 7: The process is basically the same as that of Example 2, except that the rough rolling oil, the intermediate rolling oil and the finishing rolling oil are the same, and their compositions are calculated by mass percentage as follows: 5.8% ester additives, 1.5% alcohol additives, 0.08% lauric acid, and the remainder 80# base oil.

[0094] Comparative Example 8: The process is basically the same as that of Example 2, except that the rough rolling oil, the intermediate rolling oil and the finishing rolling oil are the same, all of which are 80# base oil.

[0095] Comparative Example 9: The process is basically the same as that of Example 2, except that: the slit aluminum foil is sent to a box annealing furnace, and the furnace temperature is increased to 70°C at a heating rate of 1.5°C / h; the furnace temperature is increased to 180°C at a heating rate of 2°C / h, and kept constant for 45h; the furnace temperature is increased to 220°C at a heating rate of 4.5°C / h, and kept constant for 30h; the furnace temperature is reduced to 75°C at a cooling rate of 1.5°C / min, the furnace door is loosened, 1 / 5 of the furnace door is opened after 8h, half of the furnace door is opened after 5h, and the furnace is taken out of the furnace after another 3h.

[0096] Comparative Example 10: The process is basically the same as that of Example 2, except that the furnace temperature is lowered to 75°C at a cooling rate of 2.5°C / min, and the mixture is taken out of the furnace after being kept at this temperature for 15 hours. The results are shown in Table 1:

[0097] Table 1

[0098]

[0099] As can be seen from Table 1, the adjustment of rolling oil can significantly affect the number of pinholes. The random use of additives can significantly increase the number of pinholes, such as in Comparative Example 2 (the amount of acid added is very large). As the thickness of the aluminum foil is adjusted, the rolling oil also needs to be adjusted (to obtain an oil film of corresponding thickness and remove aluminum powder of corresponding size), such as Comparative Examples 6 to 8. The effect of using base oil is not good, such as Comparative Example 8. Controlling the tempering conditions can also significantly affect the number of pinholes, such as Comparative Example 1.

[0100] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

The production method of 1.8021 alloy high elongation double zero aluminum foil is characterized by: The steps include: S101 substrate selection: Select 8021 alloy billet with a specification of 0.24-0.26mm*1600mm; the element composition of the alloy is as follows by mass percentage: Fe1.2-1.5%, Si≤0.15%, Cu≤0.05%, Mn0.05-0.10%, Ti≤0.05%, and the balance is Al and unavoidable impurities; S102 Rough rolling: The substrate with a thickness of 0.24-0.26 mm is rolled twice through a rough rolling mill to obtain a coil with a thickness of 0.040-0.045 mm. The composition of the rough rolling oil is calculated by mass percentage: ester additives 5.0-5.5%, alcohol additives 1.8-2.2%, lauric acid 0.2-0.4%, and 80# base oil balance; the roughness of the rough rolling roll is 0.24-0.28 μm, and the convexity is 0.03-0.04 mm; S103 intermediate rolling: a coil with a thickness of 0.040-0.045 mm is rolled through an intermediate rolling mill to obtain a coil with a thickness of 0.0145-0.0155 mm. The composition of the intermediate rolling oil is as follows by mass percentage: ester additive 5.2-5.8%, alcohol additive 1.5-2.0%, lauric acid 0.15-0.25%, 80# base oil balance; the roughness of the intermediate rolling roll is 0.12-0.15 μm, and the convexity is 0.04-0.05 mm; S104 winding: The winding machine will double-wind two sheets of aluminum foil with a thickness of 0.0145-0.0155mm. The thickness difference between the two sheets of aluminum foil is ≤0.0005mm. The speed of double-winding is 700-800m / min. The double-winding oil is sprayed by mist, and the spray pressure is 0.55-0.65Mpa. S105 tempering: the coiled material is sent to the box-type annealing furnace, kept at 120-150℃ for 8-12h, and air-cooled after leaving the furnace; S106 finishing rolling: the finishing rolling mill rolls the coiled material to obtain aluminum foil with a single layer thickness of 0.0060-0.0065mm; the composition of the finishing rolling oil is calculated by mass percentage: ester additives 5.5-6.0%, alcohol additives 1.2-1.6%, lauric acid ≤0.1%, 80# base oil balance; the roughness of the finishing rolling roller is 0.05-0.08μm, and the convexity is 0.05-0.06mm; S107 Slitting: Slitting the aluminum foil according to the predetermined size; S108 annealing: send the cut aluminum foil to the box annealing furnace, increase the furnace temperature to 60-70℃ at a heating rate of 1-3℃ / h; increase the furnace temperature to 170-190℃ at a heating rate of 2-4℃ / h, and keep it constant for 45-50h; increase the furnace temperature to 210-230℃ at a heating rate of 4-6℃ / h, and keep it constant for 25-30h; reduce the furnace temperature to 120-150℃ at a cooling rate of 1-3℃ / min, and keep it constant for 10-15h; reduce the furnace temperature to 60-80℃ at a cooling rate of 2-4℃ / min, and keep it constant for 10-15h; loosen the furnace door, open the furnace door a little after 7-9h, half open the furnace door after 4-6h, and take it out of the furnace after another 2-4h.

2. The method for producing 8021 alloy high elongation double zero aluminum foil according to claim 1, characterized in that: The grinding wheel for the rough rolling roller is a 180-mesh ceramic grinding wheel; the grinding wheel for the intermediate rolling roller is a 180-mesh resin grinding wheel; the finishing rolling roller is first ground by a 180-mesh ceramic grinding wheel and then polished by a 320-mesh resin grinding wheel.

3. The method for producing 8021 alloy high elongation double zero aluminum foil according to claim 1, characterized in that: The composition of the rough rolling oil is calculated by mass percentage: 5.3% of ester additives, 2.1% of alcohol additives, 0.28% of lauric acid, and the balance of 80# base oil; the composition of the medium rolling oil is calculated by mass percentage: 5.6% of ester additives, 1.8% of alcohol additives, 0.15% of lauric acid, and the balance of 80# base oil; the composition of the finishing rolling oil is calculated by mass percentage: 5.8% of ester additives, 1.5% of alcohol additives, 0.08% of lauric acid, and the balance of 80# base oil; the tempering temperature is 130°C, and the tempering time is 10h.

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