A method for producing an alloy foil

Abstract

The application relates to the alloy preparation technical field, in particular to a preparation method of alloy foil. The method comprises the following steps: continuously performing ultrasonic cleaning on a cold-rolled strip blank, and then performing drying; under the condition that the roughness of a rolling mill roller and the saponification value of rolling oil are set, the dried strip blank is rolled in stages to obtain an alloy foil; wherein the strip blank after each rolling is washed and dried, and then annealed. The application solves the technical problem that the surface cleanliness of the existing alloy foil is low.

Description

A method for preparing an alloy foil Technical Field

[0001] This application relates to the field of alloy preparation technology, and in particular to a method for preparing alloy foil. Background Technology

[0002] With the rapid development of science and technology, expanded alloy foils are being used more and more widely. Depending on the actual application, these expanded alloy foils require further etching, photolithography, or electroplating. To ensure the stability of the etching, photolithography, or electroplating performance of the alloy foils, or the performance of downstream users, the surface cleanliness of the alloy foils is required.

[0003] Currently, according to the production method of expanded alloy foil, after the alloy foil is processed by rolling, straightening, stress relief heat treatment and other processes according to conventional process requirements, the surface of the alloy foil is prone to residual rolling oil marks, water marks, yellow spots, iron powder and other small impurities. Summary of the Invention

[0004] This application provides a method for preparing alloy foil to solve the technical problem of low surface cleanliness of existing alloy foils.

[0005] In a first aspect, this application provides a method for preparing an alloy foil, the method comprising:

[0006] The cold-rolled strip blank is subjected to continuous ultrasonic cleaning and then dried;

[0007] Under the conditions of setting the roughness of the rolling mill rolls and the saponification value of the rolling oil, the dried strip is rolled in stages to obtain alloy foil; wherein,

[0008] The strip blanks after each rolling process are washed and dried, and then annealed.

[0009] Optionally, the roughness of the rolling mill rolls and the saponification value of the rolling oil are set in stages to roll the dried strip to obtain alloy foil; wherein,

[0010] The strip blank after each rolling process is washed and dried, followed by annealing, including:

[0011] Under the conditions of a first set roughness of the rolling mill rolls and a first set saponification value of the rolling oil, the dried strip billet is subjected to a first rolling process to obtain a first steel plate;

[0012] Under the conditions of a second set roughness of the rolling mill rolls and a second set saponification value of the rolling oil, the first steel plate is subjected to a second rolling process to obtain a second steel plate;

[0013] Under the conditions of a third set rolling mill roll roughness and a third set rolling oil saponification value, the second steel plate is subjected to a third rolling process to obtain an alloy foil; wherein...

[0014] The strip blanks after each rolling process are washed and dried, and then annealed.

[0015] Optionally, the roughness of the first set rolling mill roll is ≤0.2μm, and the saponification value of the first set rolling oil is 50mg KOH / g~70mg KOH / g.

[0016] Optionally, the roughness of the second set mill roll is ≤0.08μm, and the saponification value of the second set rolling oil is 110mg KOH / g~130mg KOH / g.

[0017] Optionally, the roughness of the third set mill roll is ≤0.07μm, and the saponification value of the third set rolling oil is 170mg KOH / g~190mg KOH / g.

[0018] Optionally, the strip blank after each rolling is washed and dried, and then annealed; wherein,

[0019] The temperature for the first annealing is 850℃~1100℃; the temperature for the second annealing is 850℃~1050℃; and the temperature for the third annealing is 550℃~700℃.

[0020] Optionally, the drying method is air cooling, and the air cooling temperature is 60℃~90℃.

[0021] Optionally, the washing process includes rinsing and washing; wherein,

[0022] The rinsing medium is a neutral cleaning solution; the cleaning medium is deionized water.

[0023] Optionally, the alloy foil material may be graded as follows: 4J36, 4J29 and 4J42.

[0024] Optionally, under the conditions of setting the roughness of the rolling mill rolls and the saponification value of the rolling oil, the dried strip is rolled in stages to obtain alloy foil; wherein,

[0025] The strip blank after each rolling process includes washing and drying, followed by annealing, and further includes:

[0026] The alloy foil is cut, and alcohol is sprayed onto the cut and wound ends; wherein the alcohol has a purity of 99%.

[0027] The technical solutions provided in this application have the following advantages compared with the prior art:

[0028] The method for preparing the alloy foil provided in this application does not use any chemical reagents, which is more environmentally friendly. Continuous ultrasonic cleaning of the strip is more effective in removing stubborn particles remaining on the strip surface due to mechanical grinding. Controlling the roughness of the rolls helps reduce the surface roughness of the semi-finished and finished strips, and reduces the residue of rolling oil and other substances. The alloy foil prepared in this application has high surface cleanliness, providing stable performance assurance for subsequent etching, photolithography, electroplating, and use by downstream users. Attached Figure Description

[0029] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 is a schematic flowchart of a method for preparing an alloy foil according to an embodiment of this application. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0034] In this application, unless otherwise stated, directional terms such as "upper" and "lower" specifically refer to the drawing directions in the accompanying drawings. Furthermore, in the description of this application, terms such as "comprising" and "including" mean "including but not limited to." In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this document, "and / or" describes the relationship between related objects, indicating that three relationships can exist; for example, A and / or B can represent: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. In this document, "at least one" means one or more, and "more than one" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c" or "at least one of a, b, and c" can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be a single or multiple.

[0035] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0036] In a first aspect, this application provides a method for preparing an alloy foil, as shown in Figure 1, the method comprising:

[0037] S1. The cold-rolled strip is continuously ultrasonically cleaned and then dried.

[0038] S2. Under the conditions of setting the roughness of the rolling mill rolls and the saponification value of the rolling oil, the dried strip is rolled in stages to obtain alloy foil; wherein...

[0039] The strip blanks after each rolling process are washed and dried, and then annealed.

[0040] This application embodiment does not use any chemical reagents, which is more environmentally friendly; continuous ultrasonic cleaning of the strip is more effective in removing stubborn particles remaining on the surface of the strip due to mechanical grinding; controlling the roughness of the rolls is beneficial to reducing the surface roughness of the semi-finished and finished strips and reducing the residue of rolling oil and other substances.

[0041] The specific process flow for preparing alloy foil materials includes the following steps:

[0042] Cold-rolled strip preparation → strip cleaning → rolling of thick semi-finished strip → cleaning of thick semi-finished strip → heat treatment of thick semi-finished strip → rolling of thin semi-finished strip → cleaning of thin semi-finished strip → heat treatment of thin semi-finished strip → rolling of finished foil → tension leveling → cleaning of finished foil → stress-relief annealing of finished foil → shearing of finished foil → packaging.

[0043] The hot-rolled coil obtained by high-temperature hot rolling is mechanically ground to remove the oxide scale and hot-rolling defects on the surface, and then used as a cold-rolled strip blank. The thickness of the cold-rolled strip blank is 6mm to 12mm and the width is no more than 350mm.

[0044] Among them, finished foil cutting: the finished foil is cut using longitudinal shears; finished product packaging: the finished product is vacuum packaged and desiccant is placed inside the packaging.

[0045] In some embodiments, the roughness of the rolling mill rolls and the saponification value of the rolling oil are set in stages to roll the dried strip billet to obtain alloy foil; wherein,

[0046] The strip blank after each rolling process is washed and dried, followed by annealing, including:

[0047] Under the conditions of a first set roughness of the rolling mill rolls and a first set saponification value of the rolling oil, the dried strip billet is subjected to a first rolling process to obtain a first steel plate;

[0048] Under the conditions of a second set roughness of the rolling mill rolls and a second set saponification value of the rolling oil, the first steel plate is subjected to a second rolling process to obtain a second steel plate;

[0049] Under the conditions of a third set rolling mill roll roughness and a third set rolling oil saponification value, the second steel plate is subjected to a third rolling process to obtain an alloy foil; wherein...

[0050] The strip blanks after each rolling process are washed and dried, and then annealed.

[0051] The first rolling process uses a four-roll mill to roll semi-finished strip with a thickness of not less than 1.0 mm. The second rolling process uses a twenty-roll mill to roll semi-finished strip with a thickness of less than 1.0 mm. The third rolling process uses a twenty-roll mill to roll finished foil. The rolling oil used is a composite mineral rolling oil, which includes highly refined mineral oil and additives. After the third rolling process, a twenty-three-roll straightening machine is used to straighten the finished foil.

[0052] The first rolling oil should be replaced no more than 8 months, the second rolling oil no more than 6 months, and the third rolling oil no more than 5 months.

[0053] In some embodiments, the roughness of the first set mill roll is ≤0.2μm, and the saponification value of the first set rolling oil is 50mg KOH / g~70mg KOH / g.

[0054] The positive effect of controlling the surface roughness of the first set rolling mill rolls to ≤0.2μm is that it ensures the surface roughness of the thick semi-finished product is ≤0.3μm. If the roughness is too high, the surface roughness of the thick semi-finished product will increase, the surface impurities will increase, and the subsequent cleaning effect will be affected. Specifically, the roughness can be 0.2μm, 0.18μm, 0.19μm, etc.

[0055] The positive effects of controlling the saponification value of the first set rolling oil to be between 50 mg KOH / g and 70 mg KOH / g are: ensuring the lubricity of the rolling oil and maintaining the surface roughness of the thick semi-finished product after rolling. If the saponification value of the rolling oil is too high, it will increase the oil film volume to a certain extent, resulting in over-lubrication, which will cause slippage between the thick semi-finished strip and the rolls, leading to scratches, mill resonance, and poor strip shape. If the saponification value of the rolling oil is too low, it will result in a small oil film volume, insufficient lubrication, and increased surface roughness of the strip. Specifically, the saponification value can be 50 mg KOH / g, 60 mg KOH / g, 70 mg KOH / g, etc.

[0056] In some embodiments, the roughness of the second set mill roll is ≤0.08μm, and the saponification value of the second set rolling oil is 110mg KOH / g~130mg KOH / g.

[0057] The positive effect of controlling the roughness of the second set rolling mill roll to ≤0.08μm is that it ensures that the surface roughness of the thin semi-finished product is ≤0.15μm. If the roughness is too high, it will lead to an increase in the surface roughness of the thin semi-finished product, an increase in surface impurities, and affect the subsequent cleaning effect. Specifically, the roughness can be 0.08μm, 0.07μm, 0.06μm, etc.

[0058] The positive effects of controlling the saponification value of the second set rolling oil to be between 110 mg KOH / g and 130 mg KOH / g are: ensuring the lubricity of the rolling oil and maintaining the surface roughness of the thin semi-finished product after rolling; if the saponification value of the rolling oil is too high, it will lead to an increase in the oil film, resulting in over-lubrication, which will cause slippage between the thin semi-finished strip and the rolls, resulting in scratches, mill resonance, and poor strip shape; if the saponification value of the rolling oil is too low, it will lead to a small oil film, insufficient lubrication, and an increase in the surface roughness of the strip. Specifically, the saponification value can be 110 mg KOH / g, 120 mg KOH / g, 130 mg KOH / g, etc.

[0059] In some embodiments, the roughness of the third set mill roll is ≤0.07μm, and the saponification value of the third set rolling oil is 170mg KOH / g~190mg KOH / g.

[0060] The positive effect of controlling the surface roughness of the third-set rolling mill rolls to ≤0.07μm is that it ensures the surface roughness of the finished foil is ≤0.10μm. If the roughness is too high, it will lead to an increase in residual impurities on the surface, affecting the final cleanliness. Specifically, the roughness can be 0.06μm, 0.07μm, 0.05μm, etc.

[0061] The positive effects of controlling the saponification value of the third setting of the rolling oil to be 170 mg KOH / g to 190 mg KOH / g are: ensuring the lubricity of the rolling oil and ensuring the roughness of the rolled product; if the saponification value of the rolling oil is too high, it will increase the amount of oil film to a certain extent, which is not conducive to the control of the shape of the finished product; if the saponification value of the rolling oil is too low, it will lead to an increase in the surface roughness of the finished foil and an increase in residual impurities. Specifically, the saponification value can be 170 mg KOH / g, 180 mg KOH / g, 190 mg KOH / g, etc.

[0062] In some embodiments, the strip blank after each rolling is washed and dried, and then annealed; wherein,

[0063] The temperature for the first annealing is 850℃~1100℃; the temperature for the second annealing is 850℃~1050℃; and the temperature for the third annealing is 550℃~700℃.

[0064] The positive effects of using a horizontal continuous annealing furnace to heat treat thick semi-finished strips and controlling the first annealing temperature to 850℃~1100℃ are: heating the thick semi-finished strips to above the recrystallization temperature, reducing the hardness of the alloy, and enhancing its plasticity; specifically, this temperature can be 850℃, 900℃, 950℃, 1050℃, 1100℃, etc.

[0065] The positive effects of using a vertical continuous annealing furnace to heat treat thin semi-finished strips and controlling the second annealing temperature to 850℃~1050℃ are as follows: heating the thin semi-finished strips to above the recrystallization temperature reduces the hardness of the alloy, enhances its plasticity, and ensures that the grains do not grow too large, thus affecting the control of the strip shape; specifically, this temperature can be 850℃, 900℃, 950℃, 1050℃, etc.

[0066] The positive effects of using a horizontal stress-relief annealing furnace to perform stress-relief annealing on finished foil materials, and controlling the third annealing temperature to be between 550℃ and 700℃, are: reducing the residual stress of the foil material without affecting its mechanical properties. Specifically, this temperature can be 550℃, 600℃, 650℃, 700℃, etc.

[0067] In some embodiments, the drying method is air cooling, and the air cooling temperature is 60°C to 90°C.

[0068] The positive effects of controlling the air-cooling temperature to 60℃~90℃ include: accelerating the evaporation of surface moisture in cold-rolled strip; if the temperature is too high, it will significantly increase the cost of the air-cooling equipment; if the temperature is too low, it will lead to incomplete evaporation of surface moisture, causing surface rust. Specifically, the air-cooling temperature can be 60℃, 70℃, 80℃, 90℃, etc.

[0069] In some embodiments, the washing includes rinsing and cleaning; wherein,

[0070] The rinsing medium is a neutral cleaning solution; the cleaning medium is deionized water.

[0071] The neutral cleaning solution comprises a mixture of cleaning fluid and deionized water. The first washing sequence consists of rinsing, rinsing, and drying. For thick semi-finished strip, a horizontal cleaning unit is used, with a rinsing medium of 0.5%–0.8% low-concentration neutral cleaning solution and a rinsing medium of deionized water. The second washing sequence consists of rinsing, rinsing, and drying. For thin semi-finished strip, a vertical cleaning unit is used, with a rinsing medium of 0.5%–0.8% low-concentration neutral cleaning solution and a rinsing medium of deionized water. The third washing sequence consists of one rinsing, two rinsings, rinsing, and drying. For thin semi-finished strip, a vertical cleaning unit is used, with a first rinsing medium of 1.0%–1.3% high-concentration neutral cleaning solution and a second rinsing medium of 0.5%–0.8% low-concentration neutral cleaning solution and a rinsing medium of deionized water.

[0072] In some embodiments, the alloy foil grades include 4J36, 4J29, and 4J42.

[0073] 4J36 alloy foil is used in the semiconductor industry for metal photomask substrates, 4J29 alloy foil is used in solar panels, and 4J42 alloy foil is used in integrated circuit lead frames.

[0074] In some embodiments, the dried strip is rolled in stages under conditions of set mill roll roughness and rolling oil saponification value to obtain alloy foil; wherein,

[0075] The strip blank after each rolling process includes washing and drying, followed by annealing, and further includes:

[0076] The alloy foil is cut, and alcohol is sprayed onto the cut and wound ends; wherein the alcohol has a purity of 99%.

[0077] The positive effect of spraying alcohol at the shearing and winding point is to remove small amounts of surface oil brought in by the shearing equipment.

[0078] The positive effects of controlling the alcohol purity to 99% are: rapid evaporation, which can quickly dissolve residual small amounts of oil stains; if the purity is too low, the water content will be high, causing the surface of the finished foil to rust and resulting in secondary pollution.

[0079] The present application is further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the application. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to national standards. If there is no corresponding national standard, then general international standards, conventional conditions, or conditions recommended by the manufacturer are followed.

[0080] Specific steps:

[0081] Step 1: Preparation of cold-rolled strip blanks: The hot-rolled coils obtained from high-temperature hot rolling are mechanically ground to remove the oxide scale and hot-rolling defects on the surface, and then used as cold-rolled strip blanks.

[0082] Step 2: Strip cleaning: The cold-rolled strip is cleaned by a continuous ultrasonic cleaning device and then air-cooled and dried to obtain a clean strip.

[0083] Step 3: Rolling of thick semi-finished strip: Rolling of thick semi-finished strip with a thickness of not less than 1.0 mm using a four-roll mill;

[0084] Step 4: Cleaning of thick semi-finished strip: The thick semi-finished strip is cleaned using a horizontal cleaning unit. The process is carried out in sequence: rinsing, cleaning, and drying. The rinsing medium is a low-concentration neutral cleaning solution, and the cleaning medium is deionized water.

[0085] Step 5: Heat treatment of thick semi-finished strip: The thick semi-finished strip is heat treated using a horizontal continuous annealing furnace.

[0086] Step 6: Rolling of thin semi-finished strip: Rolling thin semi-finished strip with a thickness of less than 1.0 mm using a 20-roll mill;

[0087] Step 7: Cleaning of Thin Semi-finished Strip: A vertical cleaning unit is used to clean the thin semi-finished strip, performing rinsing, washing, and drying in sequence. The rinsing medium is a low-concentration neutral cleaning solution, and the washing medium is deionized water.

[0088] Step 8: Heat treatment of thin semi-finished strip: The thin semi-finished strip is heat treated using a vertical continuous annealing furnace.

[0089] Step 9: Finished foil rolling: The finished foil is rolled using a 20-roll mill;

[0090] Step 10: Straightening: The finished foil is straightened using a 23-roll straightening machine;

[0091] Step 11 Finished Foil Cleaning: A vertical cleaning unit is used to clean the thin semi-finished strip material, performing a first rinsing, a second rinsing, cleaning, and drying in sequence. The first rinsing medium is a high-concentration neutral cleaning solution; the second rinsing medium is a low-concentration neutral cleaning solution; and the cleaning medium is deionized water.

[0092] Step 12: Stress-relief annealing of finished foil: The finished foil is stress-relief annealed using a horizontal stress-relief annealing furnace;

[0093] Step 13: Cutting the finished foil: Cut the finished foil using longitudinal shears;

[0094] Step 14 Finished Product Packaging: The finished product is vacuum-packed and a desiccant is placed inside the packaging.

[0095] The specific preparation process parameters of the alloy foil are detailed in Table 1, and Table 2 shows the properties of the alloy foil.

[0096] Table 1. Preparation process parameters of alloy foil.

[0097]

[0098]

[0099] Table 2. Properties of alloy foil materials.

[0100]

[0101] This application embodiment does not use any chemical reagents, which is more environmentally friendly; continuous ultrasonic cleaning of the strip billet is more effective in removing stubborn particles remaining on the surface of the strip billet due to mechanical grinding; air-cooled drying is to remove surface water stains and prevent rusting of the strip surface. The rinsing medium is a neutral cleaning solution, which will not corrode the surface of alloy strips such as 4J36, 4J29, and 4J42; the cleaning medium is deionized water, which can avoid the corrosion of the alloy strip surface by chloride ions in the water; controlling the roughness of the rolls helps to reduce the surface roughness of the semi-finished and finished strips and reduce the residue of rolling oil and other substances. The alloy foil prepared in this application has high surface cleanliness, providing a stable performance guarantee for subsequent etching, photolithography, electroplating of the foil and its use by downstream users. From the preparation process parameters of the alloy foil in Table 1, the performance of the alloy foil in Table 2 is derived. The comparative example changed the roughness of the rolling mill rolls and the saponification value of the rolling oil, which affected the surface reflectivity of the foil to a certain extent, indicating that the cleanliness of the comparative example is lower than that of the embodiment. In summary, this application solves the technical problem of low surface cleanliness of existing alloy foil materials.

[0102] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for preparing an alloy foil, characterized in that, The method includes: continuously ultrasonically cleaning a cold-rolled strip blank, followed by drying; the thickness of the cold-rolled strip blank is 6mm~12mm, and the width is not greater than 350mm; using a four-high rolling mill, under the conditions of a first set rolling mill roll roughness ≤0.2μm and a first set rolling oil saponification value of 50mgKOH / g~70 mgKOH / g, the dried strip blank is subjected to a first rolling to obtain a thick semi-finished strip with a thickness of not less than 1mm; and the thick semi-finished strip after the first rolling is subjected to a first washing, drying, and first annealing; using a twenty-high rolling mill, under the conditions of a second set rolling mill roll roughness ≤0.08μm and a second set rolling oil saponification value of 110mgKOH / g~130 mgKOH / g, the strip blank is subjected to a first rolling to obtain a thick semi-finished strip with a thickness of not less than 1mm; and the thick semi-finished strip after the first rolling is subjected to a first washing, drying, and first annealing. Under conditions of KOH / g, the thick semi-finished strip after the first annealing is subjected to a second rolling to obtain a thin semi-finished strip with a thickness of less than 1.0 mm. The thin semi-finished strip after the second rolling is then subjected to a second washing, drying, and second annealing. Using a 20-roll mill, under the conditions of a third-set mill roll roughness ≤0.07 μm and a third-set rolling oil saponification value of 170 mg KOH / g~190 mg KOH / g, the thin semi-finished strip after the second annealing is subjected to a third rolling to obtain a finished foil. The finished foil is then subjected to a third washing, drying, and third annealing. The first annealing temperature is 850℃~1100℃, the second annealing temperature is 850℃~1050℃, and the third annealing temperature is 550℃~700℃. The first washing sequence is rinsing followed by cleaning, with the rinsing medium being a 0.5%~0.8% low-concentration neutral cleaning solution. The medium is deionized water; the second washing sequence is rinsing and rinsing, with the rinsing medium being 0.5%~0.8% low-concentration neutral cleaning solution and the rinsing medium being deionized water; the third washing sequence is rinsing once, rinsing twice, and rinsing, with the rinsing medium being 1.0%~1.3% high-concentration neutral cleaning solution; the rinsing medium being 0.5%~0.8% low-concentration neutral cleaning solution and the rinsing medium being deionized water; the alloy foil material grades include: 4J36, 4J29, and 4J42.

2. The method according to claim 1, characterized in that, The drying method is air cooling, and the air cooling temperature is 60℃~90℃.

3. The method according to claim 1, characterized in that, The method further includes: cutting the finished foil and spraying alcohol on the cut winding section; wherein the alcohol purity is 99%.

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