Aluminum foil overview

Aluminum foil is widely used in food, beverage, cigarette, pharmaceutical, photographic base, household daily necessities, etc. due to its excellent performance, and is commonly used as its packaging material; electrolytic capacitor material; insulation materials for buildings, vehicles, ships, houses, etc. As a decorative gold and silver wire, wallpaper and all kinds of stationery printed matter and light industrial products decorative trademark. In the various applications described above, the most effective performance of aluminum foil is as a packaging material. Aluminum foil is a soft metal film that not only has moisture, air, shading, abrasion resistance, freshness, non-toxic and tasteless, but also has an elegant silver-white luster. It is easy to handle beautiful patterns of various colors and patterns, so it is more susceptible to people’s influence. In particular, after the aluminum foil is combined with plastic and paper, the shielding properties of the aluminum foil are combined with the strength of the paper and the heat sealing property of the plastic, thereby further improving the shielding performance of water vapor and air, and the ultraviolet rays and bacteria necessary as packaging materials. , greatly expanded the application market of aluminum foil. Since the packaged articles are sufficiently isolated from external light, moisture, gas, etc., the package is well protected. Especially for the packaging of retort foods, the use of such a composite aluminum foil material at least ensures that the food does not deteriorate for more than one year. In addition, heating and unpacking are very convenient and very popular among consumers.

With the improvement of people’s living standards and the development of tourism, the demand for beverages and canned foods such as beer and soda is increasing. These require modern packaging and decoration to promote competition in the international market. In order to meet market demand, packaging materials such as plastic film and spray foil have been developed, but their overall performance is not as good as overcoating and lamination. Therefore, it can be said that aluminum foil is a packaging material having various excellent properties and perfection, and has fully demonstrated its wide application prospect in many fields.

In order to improve the rolling efficiency and quality of aluminum foil products, modern aluminum foil rolling mills are developing in four directions: large volume, wide width, high speed and automation. The roll width of the modern aluminum foil rolling mill reaches 2200mm or more, the rolling speed reaches 2000m / min or more, and the coil weight reaches 20t or more. The corresponding level of mill automation has also been greatly improved, the thickness control system (AGC) is generally installed, and most are equipped with a shape meter (AFC). The aluminum foil industry is facing a period of rapid development.

Classification

thickness
Aluminum foil can be divided into thick foil, single zero foil and double zero foil according to the thickness difference.
1 thick foil (“heavy gaugefoil”): a foil having a thickness of 0.1 to 0.2 mm.
2 “medium gauge foil”: a foil having a thickness of 0.01 mm and less than 0.1 mm/.
3 “light gauge foil”: The so-called double-zero foil is a foil with two zeros after the decimal point in its thickness, usually aluminum foil with a thickness less than 0.01, ie 0.005~0.009mm aluminum foil . In foreign countries, an aluminum foil having a thickness of ≤ 40 ltm is sometimes referred to as a “light gauge foil”, and an aluminum foil having a thickness of > 40 btm is collectively referred to as a “heavy gauge foil”.
shape
The aluminum foil can be divided into a rolled aluminum foil and a sheet aluminum foil according to the shape. Most of the aluminum foil deep-processing wool is supplied in rolls, and only a few hand-made industrial packaging uses sheet-like aluminum foil.
Aluminum foil can be classified into hard foil, semi-hard foil and soft foil according to the state.
1 Hard foil: Aluminum foil that has not been softened (annealed) after rolling, and has no residue on the surface without degreasing. Therefore, the hard foil must be degreased before printing, lamination, coating, and can be used directly if it is used for forming.
2 semi-hard foil: aluminum foil hardness (or strength) between the hard foil and the soft foil, usually used for forming.
3 soft foil: aluminum foil which is softened after being fully annealed after rolling, the material is soft and there is no residual oil on the surface. Soft foils are used in most applications, such as packaging, composites, and electrical materials.
surface condition
The aluminum foil can be divided into a light aluminum foil and a double-sided aluminum foil according to the surface state.

1 Single-sided aluminum foil: Double-rolled aluminum foil, which is bright after splitting, and the surface is black. Such aluminum foil is called a light aluminum foil. The thickness of a side of a light aluminum foil usually does not exceed 0.025 mm.
2 double-sided aluminum foil: single-rolled aluminum foil, the two sides are in contact with the rolls. The two sides of the aluminum foil are divided into mirror two-sided aluminum foil and ordinary two-sided aluminum foil due to the different surface roughness of the rolls. The thickness of the two-sided aluminum foil is generally not less than 0.01 mm.
Processing status
Aluminum foil can be divided into plain foil, embossed foil, composite foil, coated foil, colored aluminum foil and printed aluminum foil according to the processing state.
1 plain foil: aluminum foil without any other processing after rolling, also called light foil.
2 embossed foil: aluminum foil with various patterns on the surface.
3 composite foil: a composite aluminum foil formed by laminating aluminum foil and paper, plastic film and cardboard.
4 coated foil: aluminum foil coated with various types of resin or lacquer on the surface.
5 color aluminum foil: the surface is coated with a single color of aluminum foil. 6 Printing aluminum foil: Aluminum foil which is formed by printing various patterns, patterns, characters or pictures on the surface, which can be one color, up to 12 colors.
The soft aluminum foil can be further pressed into a four-zero foil for high-end decoration.

Characteristics

The aluminum foil has a clean, hygienic and shiny appearance. It can be integrated with many other packaging materials, and the surface of the aluminum foil is better than other materials. In addition, the aluminum foil has the following characteristics:
(1) The surface of the aluminum foil is extremely clean and hygienic, and no bacteria or microorganisms can grow on its surface.
(2) Aluminum foil is a non-toxic packaging material that can be in direct contact with food without any concern that may endanger human health.
(3) Aluminum foil is an odorless and odorless packaging material that does not impart any odor to the packaged food.
(4) If the aluminum foil itself is not volatile, it itself and the packaged food will never dry or shrink.
(5) There is no oil penetration of the aluminum foil at high temperatures or at low temperatures.
(6) Aluminum foil is an opaque packaging material, so it is a good packaging material for products exposed to sunlight, such as margarine.
(7) Aluminum foil has good plasticity, so it can be used to package products of various shapes. It can also be used to create containers of various shapes.
(8) The aluminum foil has a large hardness and a large tensile strength, but its tear strength is small, so that it is easily torn.
(9) The aluminum foil itself cannot be heat-sealed and must be coated with a heat-sensitive material such as pe to be heat-sealed.
(10) When aluminum foil is in contact with other heavy metals or heavy metals, there may be adverse reactions.

Rolling

Particularity of aluminum foil rolling
In the production of double-sheet foil, the rolling process of aluminum foil is divided into three processes: rough rolling, medium rolling and finishing rolling. From the perspective of process, it can be roughly divided from the thickness of the rolling outlet. The general method is that the outlet thickness is greater than Or equal to 0.05mm for rough rolling, the outlet thickness is between 0.013 and 0.05 for medium rolling, and the outlet for thickness of less than 0.013 mm and the double-rolled finished product are finish rolling. The rough rolling is similar to the rolling characteristics of the aluminum strip. The thickness control mainly depends on the rolling force and the back tension. The rough rolling processing rate is very small. The rolling characteristics are completely different from the rolling of the aluminum strip and the aluminum foil rolling. The particularity of its characteristics mainly includes the following aspects:
(1) Aluminum strip rolling. In order to make the aluminum strip thinner mainly depends on the rolling force, the automatic thickness control method is the control method of the constant roll joint as the main body of the AGC. Even if the rolling force changes, the roll gap can be adjusted at any time to maintain a certain value of the roll gap. Consistent plate strip. Since aluminum foil is rolled to medium finish rolling, since the thickness of the aluminum foil is extremely thin, the rolling force is increased during rolling, and the elastic deformation of the roll is easier than the plastic deformation of the material to be rolled, and the elastic flattening of the roll cannot be performed. Neglected, the rolling and flattening of the roll determines that the rolling force does not function as a rolled sheet in aluminum foil rolling. The aluminum foil rolling is generally roll-free rolling under constant pressure conditions, and the thickness of the aluminum foil is adjusted. Mainly depends on the adjusted tension and rolling speed.
(2) Rolling. For an extremely thin aluminum foil having a thickness of less than 0.012 mm (the thickness is related to the diameter of the work roll), since the roll is elastically flattened, it is very difficult to use a single-rolling method, so the double-rolling method is adopted, that is, A method of adding lubricating oil to the middle of two aluminum foils and then rolling them together (also called rolling). The lamination rolling can not only roll out extremely thin aluminum foil which cannot be produced by single rolling, but also reduce the number of broken strips and improve labor productivity. This method can mass produce single-sided aluminum foil of 0.006 mm to 0.03 mm.
(3) Speed ​​effect. In the aluminum foil rolling process, the phenomenon that the thickness of the foil becomes thinner with the degree of rolling degree is called the velocity effect. The explanation of the mechanism of velocity effect still needs to be studied in depth. The reasons for the speed effect are generally considered to have the following three aspects:
1) The friction state between the work roll and the rolled material changes, and as the rolling speed increases, the amount of the lubricating oil is increased, so that the lubrication state between the roll and the rolled material changes. The coefficient of friction is reduced, the oil film becomes thicker, and the thickness of the aluminum foil is reduced.
2) The change of the rolling mill itself. In a rolling mill with a cylindrical bearing, as the rolling speed increases, the roll neck floats in the bearing, so that the two interacting loaded rolls will move in a mutually abutting direction.
3) The processing softens when the material is deformed by rolling. The rolling speed of the high-speed aluminum foil rolling mill is very high. As the rolling speed increases, the temperature of the rolling deformation zone increases. According to the calculation, the metal temperature of the deformation zone can rise to 200 ° C, which is equivalent to an intermediate recovery annealing. Process softening of rolled materials.
Formulate the principle of aluminum foil rolling process
1 Determination of the total processing rate The total processing rate refers to the total degree of deformation of the foil after the recrystallization annealing to the finished product. In general, the total processing rate of the 1 series can reach more than 99%, and some 8 series products can also reach this value, but the total processing rate of the aluminum alloy foil is generally below 90%.
Determination of the pass rate of 2 passes The determination of the pass rate is the core of the rolling process. The pure aluminum series products can achieve a pass rate of 65%, and the first pass after the blank is annealed. The processing rate is generally about 50%.
Rolling thickness
Thickness measurement methods for aluminum foil rolling mainly include eddy current thickness measurement, isotope ray thickness measurement and X-ray thickness measurement. X-ray thickness measurement is one of the most common thickness measurement methods used in current aluminum foil production, especially in high speed aluminum foil rolling mills. Thickness control method for aluminum foil rolling: rolling force control, tension control, rolling speed control, tension/speed, speed/tension control

Antiseptic

The main cause of corrosion is mainly due to moisture or water in the production process and during the circulation process. Therefore, controlling the generation of corrosive waste is mainly to prevent the aluminum foil from coming into contact with water.
Anti-corrosion measures:
1 Strengthen the management of the air dryer to ensure that there is no moisture in the compressed air.
2 Strengthen the management of rolling oil, and its water content is controlled below 400×0.000001.
3 Aluminum foil rolls should be packaged in a sealed package, and an appropriate amount of desiccant should be placed in each roll.
4 The humidity of the wooden shaft and the box board of the package is not more than 18%, and the temperature of the packaged aluminum coil is not more than 45 degrees Celsius.
5 From the low temperature area to the area with high temperature and high humidity, do not open the sealed package immediately. 6 The workshop and warehouse roofs are exposed to rain and snow. Aluminum foil rolls should not be placed.
7 When transporting aluminum foil from a low temperature zone to a high temperature zone, it is necessary to strengthen the sealing of the package and, if necessary, add a desiccant.
8 When packaging aluminum foil products in the rainy season, it is necessary to strengthen the sealed packaging and add desiccant.

Prospects

(1) air conditioning foil
The air-conditioning foil is a special material for manufacturing heat exchanger fins for air conditioners, and the air-conditioning foil used in the early days is a plain foil. In order to improve the surface properties of the plain foil, an anti-corrosive inorganic coating and a hydrophilic organic coating are applied before forming to form a hydrophilic foil. The hydrophilic foil accounts for 50% of the total amount of the air-conditioning foil, and its use ratio is further increased. There is also a water-repellent foil that provides a hydrophobic effect on the surface of the fins to prevent condensation from adhering. The technique for improving the surface defrosting property of the water-repellent foil is for further study, and actual production is rare.
The thickness of the air-conditioning foil is from 0.1 mm to 0.15 mm. With the development of technology, air-conditioning foils have a tendency to further reduce the thickness of Japan’s leading products of 0.09mm. In an extremely thin state, the aluminum foil should have good formability, its structure and properties must be uniform, metallurgical defects are small, anisotropy is small, and strength is required, ductility is good, thickness is uniform, and flatness is good. The specifications and alloys of air-conditioning foils are relatively simple and suitable for large-scale production, but their market is seasonal. For professional manufacturers of air-conditioning foils, it is difficult to solve the contradiction between the shortage in the peak season and the almost no demand in the off-season.
Due to the strong market demand, the production capacity and technical level of air-conditioning foils in China have been continuously improved in recent years. Nowadays, large, medium, small, high, medium and low production air-conditioning foils have been formed. Some large enterprises such as Huabei Aluminum and Bohai Aluminum have basic product quality. Has reached the international advanced level. Due to the overcapacity in the domestic market, the market competition is extremely fierce.
(2) Cigarette packaging foil
China is the world’s largest cigarette production and consumption country. At present, there are 146 large-scale cigarette factories in China, with an annual output of 34 million large cigarettes, basically using cigarette foil packaging, of which 30% use spray foil and 70% use calender Aluminum foil, calendered aluminum foil consumption of 35,000 tons, with the increase in people’s health awareness and the impact of foreign imports of cigarettes, the growth of demand for tobacco foil has slowed significantly, is expected to increase slightly in recent years. China’s cigarette packaging foil accounts for 70% of the total volume of double-zero foil. At present, there are two or three companies in China that can produce high-quality cigarette foil. The technical level is equivalent to the international level, but the overall quality of domestic cigarette foil has a certain gap with international standards.
(3) Decorative foil
The decorative foil is a decorative material applied in the form of aluminum-plastic composite, and utilizes the characteristics of good coloration of aluminum foil and high reflectance of light and heat. Mainly used for decoration of buildings, furniture and some gift boxes. The application of decorative foil in China’s construction industry began in the 1990s. It has spread rapidly from central cities such as Shanghai, Beijing and Guangzhou to the whole country. In recent years, the demand has increased sharply, generally as the decoration material for the inner wall of the building and the interior furniture. It is also widely used in the facades and interiors of commercial establishments.
The decorative foil has the advantages of heat insulation, moisture proof, sound insulation, fire prevention and easy cleaning, and the appearance is luxurious, the processing is convenient, and the construction and installation speed is fast. At present, China’s construction and home improvement industry has formed an application boom for decorative foils. With the rapid development of China’s construction industry and the increasing popularity of decorative foil applications, the demand for decorative foils will increase substantially. In addition, the use of decorative foil packaging gifts is very popular in foreign countries. In recent years, the development speed in China is very fast, and it is expected that there will be better prospects.
(four) cable foil
The cable foil is an aluminum-plastic composite foil which is formed by applying a film on one or both sides by using the sealing property and shielding property of the aluminum foil, and is used as a shield for the cable. Cable foil requires less oil on the surface, no holes, high mechanical properties, and low overall quality requirements, but the length requirements are extremely strict.
Domestic advanced cold rolling mills, rolling mills and aluminum foil roughing mills can all be produced, but the market growth is poor. The domestic demand is about 25,000 tons per year.

More than 200 aluminum technology research experts from the whole country and aluminum industry chain entrepreneurs gathered to discuss the development and future of China’s aluminum industry.

Fan Shunke, chairman of the China Nonferrous Metals Processing Industry Association, said on the 6th that in 2017 China’s aluminum foil production reached 3.65 million tons, accounting for nearly 60% of the global aluminum foil production. Among them, the export volume of aluminum foil reached 1.16 million tons and was exported to 196 countries and regions.

From December 5th to 6th, the 2018 China Aluminum Foil Industry Development (Huaibei Tunxi) Summit Forum was held in Tunxi County, Huaibei City, Anhui Province. More than 200 aluminum technology research experts from the whole country and aluminum industry chain entrepreneurs gathered to discuss the development and future of China’s aluminum industry.

Fan Shunke believes that in China’s aluminum processing industry, the aluminum foil industry continues to develop at a high speed, and the industry as a whole has entered a stage parallel with advanced countries. The production capacity is large, the variety is complete, the process is optimal, and the cost advantage is obvious. It is prominently manifested in aluminum foil production and domestic consumption. Steady growth, global leadership in process equipment, and strong product competitiveness.

Fan Shunke said that Huaixi Tunxi County has become a bright spot in China’s aluminum processing industry. The pattern of “Southern Copper and North Aluminum” in Anhui Province is taking shape. The aluminum foil enterprises have formed a preliminary gathering in Tunxi, and the characteristics of cluster development show that there is huge room for future development. .

The reporter learned that Suixi County has been focusing on the implementation of the non-ferrous metal industry adjustment and revitalization plan in Anhui Province in recent years, insisting on the breakthrough of the aluminum-based materials industry, creating a “100 billion plate” in the aluminum industry, and increasing the chain and chain of the aluminum industry. Strong chain.

Zhao Dezhi, secretary of the Luxi County Party Committee, said that since it was approved as the second batch of strategic emerging industry gathering and development bases in Anhui Province and the National Torch Characteristic Industrial Base, there have been more than 50 aluminum processing enterprises in Luxi County, with more than 70 kinds of aluminum materials processed annually. The capacity of 10,000 tons. From January to October 2018, the total output value of the aluminum industry was nearly 20 billion yuan.

Ge Lixin, Secretary-General of the National Nonferrous Metals Standardization Subcommittee, introduced the green manufacturing standardization action plan for China’s aluminum processing industry. She said that Chinese standardization workers have been working hard to guide the aluminum foil industry to improve quality and guide enterprises to take a sustainable development path and lead the high-quality development of the aluminum foil industry.

In the summit forum, the Tunxi Aluminum-based New Materials Academician Workstation and the Weibei Aluminum Materials Industry and Technology Research Institute were successfully unveiled. At the same time, the Suixi County Investment Promotion Conference was successfully held, and the amount of on-site contracted projects reached 10 billion yuan.

Unlike the hot car sales in previous years, this year’s car market seems to be particularly early. According to the data of the Association, the retail sales of narrow-seat passenger cars in China was 1,904,525 vehicles in September this year, down 13.2% year-on-year. The decline continued to expand to double digits; the cumulative sales of narrow-seat passenger cars in January-September totaled 6,684,812. The year-on-year growth rate was -0.6%, and there was a rare cumulative year-on-year negative growth. The auto market has experienced a year-on-year decline in sales growth for three consecutive months, dropping to the “freezing point” in the past seven years. However, in the global environment of the automobile market full of chilly and chilly, the new energy vehicle market is in the ascendant, and the growth rate of new energy vehicle sales is unique, attracting major auto giants to increase the layout. The industry believes that new energy vehicles will welcome global heavy volume. With the opening of new energy vehicles, companies and investment groups from all walks of life are willing to enter this capital. Nanshan Aluminum also took the lead in entering the market by taking advantage of the new energy vehicle. On September 6-7, 2018, SMM held the “2018 China Aluminum & Silicon Processing Industry Chain Supply and Demand Trading Summit”. The representative from Nanshan Aluminum Industry conducted a thorough analysis of the current status and development trend of battery aluminum foil, in addition to Nanshan. Aluminium’s leading technology and management experience in the industry also gave a wonderful speech on the future trend of battery aluminum foil.

 

The aluminum foil industry generally refers to battery aluminum foil as battery foil. Since 2015, the rapid development of the power battery industry is the trigger for the development of the battery foil boom in the aluminum foil industry. In just three years, the number of domestic battery foil manufacturers has rapidly increased from four to five to more than a dozen. Aluminium foil products have grown so rapidly in China.

 

According to lithium ion battery use classification: power battery foil, consumer battery foil, energy storage battery foil. At present, the largest demand is power battery foil, accounting for about 50% to 55%. The consumer battery market is basically saturated. The demand for power battery foil will increase further in the future. The energy storage battery foil will gradually increase its power, so the battery foil market is still There is room for growth.

 

Key quality requirements for battery aluminum foil

  1. Mechanical properties:

Battery foil customers generally pay attention to the mechanical properties first. Different customers have different requirements on mechanical properties. Most customers want high tensile strength and high elongation. The mechanical properties mainly depend on the design of the chemical composition and the billet production process. It is possible to design a battery foil with various mechanical properties using an alloy grade.

 

2, thickness and areal density

The thickness and the areal density have an impact on the uniformity of the customer’s carbon coating and coating of the positive electrode material. The mainstream customers focus on the single roll thickness/density density fluctuation, batch thickness/area density fluctuation, and customers will pay attention to CPK, PPK, etc. Process capability indicators. The thickness is mainly influenced by the billet and the rolling mill, and the high-precision, state-stabilized mill can bring about the desired thickness level.

3, surface wetting tension

The surface wetting tension of the battery foil affects the quality of the carbon coated and coated positive electrode material. The low surface wetting tension usually leads to defects such as leakage coating, poor coating, and shrinkage of the edge of the coating material, but some customers do not The surface wetting tension is defined and is known to be different from the slurry or coating process. The surface wetting tension is affected by factors such as the amount of oil in the aluminum foil, the quality of the rolling oil, additives, etc., which is a headache.

4, pinhole

The pinholes that lithium-ion customers pay attention to are mainly distribution and size, followed by quantity. Generally, the diameter is not more than 300μm or 500μm, there is no large pinhole near the edge, and there is no periodicity, line or dense pinhole. The number of pinholes of the 12μm battery foil is generally not more than 10/m2. Hot-rolled aluminum foil can basically meet these requirements, and cast aluminum foil has a little difficulty in stability.

5, the shape quality

Battery foil shape quality test method: The amount of collapse and the degree of collapse are usually tested after applying tension, and some customers use offline shape detection equipment to quantify. As we all know, the linear shape and off-line shape of aluminum foil are not exactly the same. The final shape quality depends on the shape of the aluminum foil blank, equipment level, process parameters and operator level. The first three factors can be controlled by the system, so the operation The level of personnel is crucial.

  1. Other quality requirements Compared with traditional aluminum foil products, the application of battery foil involves safety. Therefore, the requirements for cutting quality such as trimming burrs and aluminum powder are becoming more and more strict. In addition, the quality points such as dark surface highlights, surface pits, and surface oil stains are not negligible.

The dark spot highlights only appear on single-sided photocell foils, which is also an aspect of the increased share of double-sided photocell foils in the battery foil market.

 

Battery aluminum foil quality and production difficulties

1, high strength

At present, the tensile strength is generally required to be 200 MPa or more, and each aluminum foil enterprise can basically supply in batch or small batch. Some customers require a tensile strength of 250 MPa or more. This battery foil is difficult to mass-produce and has a low yield. There are also some customers who require 280 MPa and 300 MPa or more, and have basically reached the rolling hardening limit of aluminum foil products (10μm~15μm thickness). They can be developed domestically, but it seems that there is no mass production. Only domestic production, domestic lithium battery customers are known. I have purchased it from Japan.

2, thickness reduction and strict tolerance

Thinning: Since 2016, many customers have started to have 9μm and 10μm double-sided light. This has exceeded the theoretical limit of single-sheet aluminum foil rolling. We can barely supply, but the yield is low and painful. Thickness tolerance: ±2% of existing customer requirements, even if the equipment accuracy is very high, it is difficult to meet this requirement, because it involves the horizontal and vertical thickness uniformity of the hot rolling, cold rolling and foil rolling processes, and equipment And the stability of personnel operations.

3, wide and plate shape

In order to improve production efficiency, lithium battery customers have generally increased the wide production line, the demand is 700mm~800mm width, and even more than 1000mm, which is a very big challenge for aluminum foil enterprises. Our equipment capacity can be 1700, 1800, 2000mm width, why not want to roll around 1600mm to cut the width of 700mm~800mm, the only reason is the shape quality. For the battery foil with ultra-high tensile strength, the degree of work hardening is high, the shape control is extremely difficult, and the shape quality will be the biggest problem that is difficult to mass-produce.

4, the system, packaging methods, etc. are complex

Power battery foil involves the automotive industry. The ITAF 16949 is a basic requirement. The system requires too much content and requires a professional team to implement it. The requirements of different customers for packaging methods are also very different. In fact, the cost of aluminum foil packaging is very high. 5, surface wetting tension

Surface wetting tension often has instability problems in production, and it needs to be improved by various means. According to the information exchanged with the same industry, the means to increase the surface wetting tension is basically the same.

 

Difficulties faced by aluminum foil companies

  1. Customer requirements are getting higher and higher, complaint rate is high

At present, customers’ requirements for thickness, tensile strength and shape have reached the limit of aluminum foil equipment and production, and it is almost impossible to improve. The requirements for surface quality, pinhole and slitting quality are also getting higher and higher. This will inevitably lead to an increase in production costs, a decline in the yield, and an increase in the complaint rate.

2, a variety of battery foils, a small amount of single specifications

According to the network data, it is estimated that the demand for battery foil in China will reach 30,000 to 40,000 tons in 2020. It seems that the quantity is considerable, but there are too many requirements for alloy, thickness, width and mechanical properties, and the number of dispersion to a single specification is very small. At present, the battery foil produced by Nanshan is mainly made of 1100 and 1060 alloys, with nearly 10 kinds of thickness. The width and length of the coil are more complicated. Now, the output of several hundred tons per month is required to prepare several times of blanks. Even if this is not enough, the customer will not be fully satisfied. Increased special needs.

  1. Industry competition is intensifying, processing fees are decreasing year by year, and research and development of new products maintains advantages.

As more and more aluminum foil companies begin to produce battery foils, market competition has intensified; coupled with the transfer of pressure from lithium battery customers, the price of battery foils has also been declining year by year. In order to maintain the market advantage in the future, we only have to constantly develop new products to meet the requirements of new and old customers, but this new requirement generally has only one demand direction, which may take 1-2 years to be finalized. The battery foil research and development investment is huge, which requires enterprises to have Strong strength and firm determination.

The environmental protection requirements are improved, and the output of electronic aluminum foil is affected: the electronic aluminum foil needs to use acid in the production process, which is easy to affect the environment. Domestic environmental protection requirements have become increasingly strict, and some manufacturers have shut down their production capacity, resulting in a tight supply of electronic aluminum foil, and prices have risen slightly. Due to long-term low-profit operation, small and medium-sized factories have low enthusiasm for resumption of production, increase the cycle of environmental protection equipment, and the downstream demand is growing steadily. The tight supply of electronic aluminum foil is expected to continue. Continued price increases are a high probability event.

Environmental requirements that cannot be avoided. Refers to anodized foil and cathode corrosion foil for aluminum capacitors. The capacitance of the capacitor is positively related to the surface area of ​​the anode and cathode. The aluminum foil used in aluminum capacitors uses an etching process to increase the surface area and increase the capacitance. It is inevitable to use acidic substances such as hydrochloric acid and nitric acid in the etching process, which is easy to affect the environment. The production of electronic aluminum foil is bound to increase environmental protection equipment to reduce the impact on the environment.

The enthusiasm for the re-production of the electronic aluminum foil industry is not high. Before the 2012, the electronic aluminum foil industry developed rapidly due to the rapid development of the industry, and the gross profit margin was low. After 2013, due to overcapacity, profits will fall, and the increase in environmental protection equipment may raise the cost of products. Some of the original manufacturers have lower operating rates, and the enthusiasm for environmental protection investment is not high. Environmental protection requirements are becoming more and more strict. Under the current situation that the price of electronic aluminum foil has risen slightly, the enthusiasm of enterprises to resume production through environmental protection reform is not high; the cycle of environmental protection transformation is long, and even if funds are raised for transformation, it will be difficult to resume production in the short term.

The downstream demand is growing steadily, and the price continues to rise is a high probability event. The main downstream aluminum capacitors of electronic aluminum foil are widely used in the electronics field. Emerging application markets and automotive electronics are expected to continue to drive steady growth in the capacitor market. The trend of supply shortage of electronic aluminum foil is expected to continue, and the price continues to rise is a high probability event.

Speaking of concept stocks, I think friends who are stocks may know that their concept stocks are a combination of stock picks of the same kind. After saying this, everyone must know what I want to say, yes, definitely about concept stocks. Related information, what are the 2018 concept stocks on electronic aluminum foil?

Xinjiang Zhonghe (7.08 +1.72%, BUY): Xinjiang Zhonghe is China’s largest manufacturer of high-purity aluminum and electronic aluminum foil, achieving the transformation from smelting industry to electronic new material industry, or the world’s largest high-purity aluminum R&D And one of the production enterprises, product technology and quality have reached the world’s advanced level. At present, the company has formed a “high-purity aluminum-electronic aluminum foil-electrode foil” industrial chain with “high-purity aluminum, electronic aluminum foil and electrode foil” as the leading products. Among them, the share of high-purity aluminum and electronic aluminum foil products in the domestic market is in a leading position.

Xinjiang Zhonghe 600888: The company currently has a high-purity aluminum production capacity of 42,000 tons, an electronic aluminum foil production capacity of 35,000 tons, and an electrode foil production capacity of 16 million square meters. In the first half of 2017, with the gradual recovery of aluminum prices, the company’s main electronic new materials business maintained a growth trend, in which high-purity aluminum achieved sales revenue of 251 million yuan, an increase of 7.07%, electronic aluminum foil sales revenue of 290 million yuan, an increase of 22.61 %, electrode foil realized sales income of 464 million yuan, an increase of 45.61%. Optimistic about the demand for aluminum capacitors in new consumer electronics.

Nanshan Aluminum (6.90 +2.07%, BUY): Nanshan Aluminum is the only listed company in China with aluminum as its main business. It has formed a line from energy, alumina, electrolytic aluminum to aluminum profiles, high precision aluminum sheets and strips. Foil is the world’s only short-distance and complete aluminum industry chain, and its scale and output continue to be at the forefront of large-scale aluminum industry enterprises. Shandong Nanshan Aluminum Material Factory is the pillar enterprise of the company and is the designated manufacturer of aluminum alloy building profiles by the Ministry of Construction.

Chang Aluminum Co., Ltd. (8.40 +1.69%, BUY): Chang Aluminum Co., Ltd. is an aluminum processing enterprise specializing in the production of aluminum foil, hydrophilic coated aluminum foil and aluminum sheet and strip. It is one of the top ten enterprises in China and the first batch of 22 key private enterprises in Jiangsu Province. Technology companies. The company has aluminum processing and deep processing production facilities from aluminum ingot casting, hot rolling (including continuous casting and rolling), rough finishing, finishing, heat treatment, coating and shearing; it has annual production of 100,000 cast and rolled billets. Tons (including hot rolling of 80,000 tons, casting and rolling 21,000 tons), 50,000 tons of plain aluminum foil and aluminum foil wool, and 42,000 tons of hydrophilic coated aluminum foil, the products are exported to Japan, South Korea, Southeast Asia, the United States, etc. 10 Multiple countries or regions.

Electronic aluminum box 掀 out of stock tidal stocks related stocks

According to relevant reports, due to the shortage of aluminum foil in the upstream of the capacitor components, coupled with the suspension of orders from the large chip resistors, the passive components of aluminum capacitors have risen again, and related concept stocks have risen and stopped on Wednesday. Taiwan industry insiders said that the current price surge of aluminum capacitors is mainly due to the shortage of aluminum foil materials in mainland China, and may start a second wave of price increases in the future. As environmental pressures increase, out-of-stock prices will continue. Among the A shares, Xinjiang Zhonghe 600888 formed an integrated industrial chain from high-purity aluminum to electrode foil; Huafeng 002806 is one of the largest low-pressure foil-forming enterprises in China, and can pay attention to these two stocks.

Financial sector website news, aluminum foil concept stocks rose in early trading on December 28, as of press time, Xinjiang Zhonghe rose more than 7%, Huafeng shares rose more than 6%.

According to Taiwan media reports on the 27th, due to the shortage of aluminum foil in the upstream components of capacitor components, coupled with the suspension of orders from large-scale chip resistors, the rise in prices of passive components such as aluminum capacitors, the related concept stocks rose on Wednesday. Aluminum foil material factory Lideng (6175.TW) daily limit, the stock price hit a record high, rising more than 80% in the fourth quarter. Capacitor manufacturers Kaimei (5317.TW) and Zhibao (2375.TW) all traded at a daily limit, with gains of 97% and 51% in the fourth quarter.

Taiwan industry insiders said that the current price surge of aluminum capacitors was mainly due to the shortage of aluminum foil materials in mainland China. It is estimated that the impact of the shortage in November and December is between 15% and 25%. Out of stock directly led to price increases, aluminum foil material stocks rose about 8%-10% in October-November, and may start a second wave of price increases in the future. Electrode foil processed from electronic aluminum foil is a key raw material for the manufacture of aluminum capacitors, accounting for 30%-70% of the production cost. In recent years, the demand for new energy vehicles and smart phone fast charging has exploded, and the aluminum capacitor market has developed rapidly, driving the demand for electrode foil. As electrode foil production will emit acid waste water and irritating gases, this year’s environmental pressure will lead to the suspension of production capacity, and the shortage of stock prices may continue.

 

1

Definition

The electronic aluminum foil is an aluminum foil processed by a series of calendering, cleaning and cutting processes on a high-purity aluminum ingot, and is a key raw material for producing an aluminum electrolytic capacitor.


2

Introduction

After the aluminum foil is processed into a foil, it is subjected to surface etching treatment and reoxidation treatment, and then subjected to winding processing to form a capacitor. The aluminum foil before the etching is called a light foil, and the corroded aluminum foil is called a corrosion foil, and the aluminum foil after the reoxidation treatment is called a foil. Electronic aluminum foil refers to light foil, which is a key raw material for the production of aluminum electrolytic capacitors. It is divided into electronic aluminum foil and electrode foil according to the order of the manufacturing process. The electrode foil includes corrosion foil and chemical foil.

The electronic aluminum foil together with the electrolyte accounts for 30%-70% of the raw material cost of the aluminum electrolytic capacitor (which varies depending on the size of the capacitor). It can store electrical energy and can be used as the positive and negative electrodes of electrolytic capacitors.

3

Electronic aluminum foil industry chain list

As one of the most basic electronic components, aluminum electrolytic capacitors are widely used in various electronic products such as electronic information industry and home appliances. They have the characteristics of small size, large capacity and low cost, especially the price per unit of electricity. The capacitor is the cheapest, in line with the development trend of information products, and is widely used in telecommunications, home appliances, automobiles, electronics, aviation, new materials and other industries. The market demand is extremely large. At present, the output of aluminum electrolytic capacitors accounts for 45% of the total capacitor output. .

4

Electronic aluminum foil process

The electronic aluminum foil is a high-purity aluminum foil which is formed by hot-rolling a fine aluminum (high-purity aluminum) aluminum ingot into an aluminum sheet, and further cold rolling and annealing. The specific production process of the electronic aluminum foil includes: melting casting – soaking – hot rolling – pre-annealing – cold rolling – intermediate annealing – cold rolling – foil rolling – slitting – performance testing – packaging.


5

Classification of electronic aluminum foil

The electronic aluminum foil can be classified into a high voltage anode foil, a low pressure anode foil, a negative electrode foil, and the like. The high-voltage anode foil is column-like corrosion, the low-pressure anode foil is spongy corrosion, and the anode foil of the medium-pressure section is worm-like corrosion.

High-pressure anode foils can be divided into two categories, one is high-quality high-pressure foil; the other is ordinary high-pressure foil. The high-quality high-voltage anode foil is characterized by “two high and one thin”, namely high-purity, high-cubic texture and thin surface oxide film. These products are of high quality, but high cost, aluminum purity >99.99%, cubic texture 96%, vacuum heat treatment at 10-3pa ~ 10-5Pa. Ordinary high-pressure anode foil is an economical and practical high-pressure anode foil with aluminum purity >99.98%, cubic texture >92%, and vacuum heat treatment under 10-1pa~10-2pa conditions.

The negative electrode foil has a soft state and a hard state. Japan is dominated by soft electrochemical corrosion, while Western Europe is dominated by hard chemical corrosion. Both have their own advantages and disadvantages. The soft state uses high purity aluminum foil (>99.85%), no copper, excellent quality, but high cost; the hard state uses low purity copper-containing aluminum foil, and the cost is low.

6

Major producers

The production of electrode foil needs to be rolled and etched into two stages by aluminum foil. It is linked to the two industries of aluminum processing and capacitor manufacturing. The main processes are relatively independent and the difference is large. Therefore, some enterprises use the aluminum electrolytic capacitor production industry as the background. The electrode foil production line is expanding; some enterprises use aluminum refining or aluminum processing as the background to expand into high-purity aluminum smelting, aluminum foil rolling and even electrode foil production; some enterprises specialize in electrode foil production and aluminum electrolytic capacitor production. Among them, professional electrode foil manufacturers and aluminum electrolytic capacitor manufacturers are the main enterprises in the production of electrode foil, while electronic aluminum foil is mainly produced by aluminum processing enterprises. At present, there are more than 40 domestic electronic aluminum foil manufacturers.

7

Application of electronic aluminum foil

Electronic aluminum foil is widely used in capacitors. Capacitors can be divided into three categories: aluminum electrolytic capacitors, ceramic capacitors and film capacitors. Among them, aluminum electrolytic capacitors are the most widely used varieties of all electronic capacitor products. The rapid development of China’s capacitor manufacturing industry has led to an increasing demand for electronic aluminum foil. Due to the high difficulty in the production of electronic aluminum foil required for the manufacture of capacitor anodes, the current domestic supply capacity is still insufficient in the medium and high-end products, but with The supply of domestic aluminum foil products has been increasing, and this situation has changed significantly.

In 2016, China’s electronic aluminum foil production capacity was about 85,000 tons, an increase of 0.7 million tons from the 78,000 tons in 2015. In 2016, China’s electronic aluminum foil industry output was about 51,900 tons, an increase of 2.77% from 2015’s 5.05 million tons; 2016 China’s electronic aluminum foil industry market consumption of about 47,900 tons, an increase of 3.01% compared with 46,500 tons in 2015, the market size of China’s electronic aluminum foil industry in 2016 was about 1.207 billion yuan, an increase of 5.97% from 1.139 billion yuan in 2015.

8

Technical analysis of electronic aluminum foil

The production of electronic aluminum foil is a precision processing process, and the quality of the product has an important relationship with the advanced level of raw materials, control systems and production equipment. From a global perspective, although the production of electronic aluminum foil in China is developing rapidly, European and American companies still have advantages in advanced technology, especially in high-voltage electronic aluminum foil. Since the electronic aluminum foil products have strict requirements on process technology, equipment technology and production management level, it is necessary to strictly follow the process flow and follow the characteristics of the equipment in order to produce qualified products.

In recent years, with the advancement of science and technology, the main equipment used in the production of electronic aluminum foil products has been domestically produced. Nowadays, the domestic electronic aluminum foil factory uses domestically produced equipment to produce products, and the quality level has caught up to even exceed the products produced by Japan and South Korea. In the choice of control system, the technology possessed by major domestic manufacturers is not very mature, and most choose foreign control systems. Technically, domestic production lines and production processes are still imitating and using foreign technology, or choosing a technology model for cooperation with foreign capital.

In order to continuously improve the product characteristics of aluminum electrolytic capacitors, China has many related technological improvements in aluminum foil processing. The use of high-purity, high-performance aluminum foil material greatly improves the corrosion performance of the material, and the leakage current of the formed dielectric oxide film is greatly reduced; the development of advanced corrosion and formation processes further increases the specific capacity of the anode and cathode aluminum foils, and the anode light The leakage current of the foil is further reduced. In order to reduce the size and flatten the capacitor, in recent years, progress has been made in processing technology for high specific volume and high strength of aluminum foil.

 

Food packaging foil already entered thousands of households,We often use a beverage bag, food packaging bag and container, these are made from aluminum foils.

The price of food foils usually depends on the alloy brand, specification, technical requirements and quantity.The most commonly used alloy states in China are aluminum foil of 8011/H22, 8011/H24, 8011/O and 3003/H24, and the 3003/H24 price is higher than the others.

The performance aspect is mainly about the requirement of tensile strength and elongation, High elongation makes it hard to crack, also request no oil, no smell, to ensure the requirements of food packaging.

Food foil usually uses double zero aluminum foil and single zero aluminum foil, the price is different between different thickness, usually the thinner the thickness, the higher the price.

Our company can process 8011 aluminum foil with thickness of 0.009-0.5mm for household, and aluminum container foils with different width and thickness.

Product name Alloy Temper Thickness(mm) Width(mm)
Aluminum container foils 8011 H22/24 0.022-0.15 200-1200
3003 H24 0.03-0.08 200-800
Aluminum household foils 8011 O 0.02-0.04 400-700

 

 

As people’s lives continue to improve, aluminum products are becoming more and more extensive in our lives. The issue of improving the quality of electronic aluminum foil is especially important. The production process of electronic aluminum foil is divided into two parts: calendering and finishing. In recent years, the market demand for electronic aluminum foil has gradually changed to higher quality and greater difference. The finishing technology represented by cleaning, shearing, rewinding, annealing and other processes has become very important, involving stability and improvement. The big problem of product quality and the ability to improve the ability of enterprises to meet the needs of customers has become a key issue for enterprises to survive and develop.

1 defects in the surface of aluminum foil

1.1 crater

After the aluminum foil is cleaned, it must be awakened and dried. Because of the flammable and explosive materials of the rolling mill and the cleaning agent, the ignition point is around 200 °C. The crater is in the drying process, the aluminum foil is cut by the air ball, the heat exchanger, the drying box and the like, and the solid particles are cut and the small particles are entangled between the steel roller and the aluminum foil, and the embossing is generally formed on the foil surface. Defects, reducing product quality; large particles can even cut through the foil surface, causing scrapping

1.2 oil spots

During the cleaning and rinsing process of the aluminum foil, the nozzle sprays the cleaning agent to the foil surface through a certain pressure and flow. After the cleaning agent reaches the foil surface and rebounds to the four walls, a large amount of high-concentration oil mist is generated, and the oil spot is formed over time. .

1.3 abrasions

Scratch is a common quality problem of all finishing equipment including cleaning. The mechanism is that the aluminum foil is slippery on the thin surface and the roll surface during the cleaning process, but the cause of the slip is related to machinery, electrical appliances, crafts, etc. Various aspects.

1.4 wrinkles

The thickness of the electronic aluminum foil entering the cleaning pass is generally about 0.1 mm. Due to the thinness of the incoming material, the fluctuation of the plate type, the occurrence of waves and waves, etc., the material in the cleaning process passes through the pinch roller and the squeeze roller. Wrinkles appear.

2 Measures to improve the foil surface

2.1 Improvement measures for pressure pits

The control of the crater is divided into two steps: the early stage equipment is used only in the later stage and the later stage. High-temperature oxidation of the drying equipment is unavoidable, but the oxidation-resistant stainless steel material is used in the early equipment manufacturing process, and a protective gas welding process such as argon arc welding is used, which may reduce the oxidation of the material surface and the welded portion in use in the future. The possibility. In the later stage of use, a multi-layer stainless steel filter is added to the air duct. In order to reduce the clogging of the filter and reduce the air volume, the filter can be periodically cleaned or replaced for routine maintenance.

2.2 Oil spot improvement measures

During the cleaning and rinsing process of the aluminum foil, a large amount of high-concentration oil mist will be generated in the tank body and eventually fall on the foil surface to cause pollution. Since a large amount of mist will consume cleaning agents, increase the cost of the enterprise, and the effect is not satisfactory, it is only considered to block the oil droplets to the foil surface. It is found that the oil droplets are mainly installed with an arc-shaped baffle at the top of the tank at the distance from the squeezing roller to the rinsing tank, and an oil sump is installed at the top of the rinsing tank outlet to guide the oil droplets to both sides, thereby eliminating the foil surface oil spot. .

2.3 Improvement measures for scratches and scratches

The causes of scratches are mechanical structure, electrical control and process selection.

1 For each roller not synchronized, check whether the synchronous toothed belt is tight and the bearing is lubricated in place;

2 Electrically adjust the motor parameters so that the individual drive rollers are not synchronized, and the correction of the winding diameter error control mode selects simple tension control and speed control.

3 The process tension and speed settings should match the front and rear passes, and a reasonable range should be selected.

2.4 Wrinkle improvement measures

For the poor type of material, the following measures are taken: 1. Adding several sets of S-shaped U-shaped rolls on both sides of the unwinding and winding to correct the effect; 2. Installing the plate-type adjusting rolls on both sides of the unwinding and winding. Eliminate the edge waves by adjusting the level and parallelism of the roller; 3. Eliminate the mid-wave by increasing the rubber roller or other convexity.

3 electronic aluminum foil cleaning

3.1 Status analysis

3.1.1 Importance of cleaning

Electronic aluminum foil belongs to deep processing technology, and the surface quality has a great influence on the electronic storage capacity. The small defects caused by the previous process on the surface of the aluminum foil will be amplified in the subsequent process. Therefore, only the quality of the foil surface is performed in each process in the production process. strict control.

3.1.2 Cleaning process

The cleaning process of the aluminum foil is as follows: the strip enters the device from the uncoiler and the inlet deflector roller, first passes through the lower brush roller, and a cleaning liquid is sprayed between the lower brush roller and the strip to wash the lower surface of the strip. Next, the strip passes through the upper roller, and a cleaning liquid is also sprayed between the upper roller and the strip to wash the upper surface of the strip. The strip then enters the rinse tank. Still use the same cleaning solution to spray the upper and lower surfaces of the strip. The cleaning oil on the surface of the strip was squeezed through a 2# dry roll. After the strip exits the rinsing tank, it enters the drying box, and the residual cleaning liquid on the strip is evaporated under the hot air purging. Later, the strip passes through the outlet deflecting roller and is circulated by the coiler into a roll. The cleaning is over.

4 cutting of electronic aluminum foil

4.1 Description of the status of equipment and quality defects

The shearing machines are available in different models. These devices are available in both narrow and wide widths. They have both trimming and drawing, and both single and double shafts. No matter what type of shearing machine is mainly used for unwinding, slitting, The volume is composed of three parts. As customers’ demand for aluminum foil rolls is changing to large volume, high quality, short delivery time and multiple specifications. The cutters, shafts, rollers, and dies of the shearing machine are subject to problems such as increased wear, reduced accuracy, and frequent replacement. The shearing part may cause scratches, craters, burrs and other quality defects due to the fabrication and fitting accuracy of the disc knives and knives. Due to the use and design problems of the surface roller, the take-up shaft and the die, the coiling portion may cause quality defects such as flanging, split layer, and unstable internal stress.

4.2 Causes and improvement of shear quality defects

4.2.1 Scratch

Reason: The problem of scratching is a common problem in the shearing process, and it is also a problem that is difficult to solve completely. The main cause of scratches is that the end face is misaligned by the disc knife or the knife pad when it is assembled with the knife shaft. When the aluminum foil slides over the sharp corner, the material of the lower knife or the knife pad is harder than the aluminum foil, at a specific rotation speed. Extremely small slippage occurs in a very short period of time, reflected in the point or line scratches on the material surface. Since everyone pays more attention to the machining accuracy and assembly precision of disc knives, knives and knives, we will not discuss the scratches caused by the above reasons. This paper mainly studies the following cases that are easily overlooked. Since the disc cutter becomes dull after a period of use, it is necessary to replace the new knife frequently, and the knife pad is generally fixed. The equipment and quality defects of the disc knife and the knife pad will be described each time a new disc knife is replaced. There are many different types of aluminum foil shearing machines in our company. These devices have both narrow and wide widths. Both the trimming and the long-term accumulation of the strips will cause the outer diameter of the mat to be relatively small. A batch of old disc knives is used up, and the problem of sharp corners will be more prominent after replacing a batch of new disc knives. 2 Design link problem: Aluminum foil is prone to flanging and embossing during the slitting process, mainly due to the aluminum powder sticking knife. There are two sources of aluminum powder, one is the aluminum powder attached to the surface of the aluminum foil; the other is the aluminum powder produced during the shearing process. The two parts of aluminum powder gather on the tip of the knife to make the knife dull, which causes the material surface to be turned over. When the aluminum powder falls to the material surface, a crater is generated. Improvement measures: New knives need to be replaced frequently, and the knives are generally fixed. Each time a new disc knives is replaced, the equipment and quality defects of the disc knives and knives will be polished.

4.2.2 Flanging and pressing

Reason: Aluminum foil is prone to flanging and embossing during the slitting process, mainly due to the aluminum powder sticking knife. There are two sources of aluminum powder, one is the aluminum powder attached to the surface of the aluminum foil; the other is the aluminum powder produced during the shearing process. The two parts of aluminum powder gather on the tip of the knife to make the knife dull, which causes the material surface to be turned over. When the aluminum powder falls to the material surface, a crater is generated. Improvement measures: 1 Add a set of aluminum powder purging device, purify the tool in the opposite direction, and remove the aluminum powder attached to the tool; 2 pad the felt with kerosene, diesel and other light oil and stick it on the knife. When cutting, the felt is wiped on the surface to prevent the aluminum powder from collecting. 3 Soak the knife in the inside with 5 NaOH alkali solution, heat it to 60-70 ° C, remove it, rinse it with water, and dry it. This method can be used in the knife. A protective layer is formed on the surface to reduce the amount of aluminum foil sticking.

4.2.3 Uneven surface layer and roll density uneven

Reason: The cause of the inconsistency between the end-face staggered layer and the roll density is mainly on the take-up shaft. When using the air-expansion shaft to cut the heavier roll, whether it is an inflatable pressure-holding inflatable shaft or a continuous aerated air-expansion shaft, when When the weight of the coil exceeds the support force provided by the air pressure, the weight of the coil is too large, which may cause the core to sag and the coil to be eccentric, affecting the density of the coil and the quality of the end surface. Improvement measures: The simpler measure is to replace the knife pad in time, and the second step can adopt the structure of the outer rubberized knife pad. The outer diameter is larger than the outer diameter of the disk cutter by 0.01ram-0.05ram, and the upper part is rounded and rounded. The radius is about 0.01 ram – 0.15 ram, the rubber is urethane rubber, and the hardness is ≥ HS85. The upper and lower knives usually use an external gear transmission. The number of teeth and the modulus of the upper cutter drive gear can be adjusted according to the change of the upper cutter diameter to achieve the matching purpose.

4.2.4 Jumping and toothing

Cause: Jumping and toothing are prone to problems during tool use. After the grinding of the upper knife, the total outer diameter will be reduced by 6-8 ram, and only the clearance of the upper and lower cutter transmission gears will be used for the elastic fit, and the overlap of the upper and lower knives cannot be guaranteed, so that the inner wall of the steel pipe core can provide the support and torque structure. Instead of providing the support by the shaft, the drive pin provides the structure of the rotational torque, both of which cause equipment damage and waste. Improvement measures: The upper and lower knives usually adopt external gear transmission. The number of teeth and the modulus of the upper cutter drive gear can be adjusted according to the change of the upper cutter diameter to achieve the matching purpose. By improving the winding shaft, the transmission and support functions are separated, and bearing support can ensure smooth rotation of the shaft and improve the quality of the winding. By using clutch transmission, frequent replacement caused by cone wear can be eliminated, and equipment maintenance costs can be reduced.

5 electronic aluminum foil rewinding

5.1 Technical requirements for aluminum foil rewinder

In order to ensure that the paper roll does not deform or crack during transportation and storage, it can run smoothly on printing equipment or other processing equipment. The finished paper roll must have sufficient hardness, and the inner tightness is loose and the radial hardness is evenly distributed. Therefore, the rewinder must have the following functions: 1 Set the integrator of the support roller torque so that the input speed signal is a smoothly rising ramp signal, rather than a sudden amount. By changing the integral of the given integrator to the constant, the slope of the E-slope of the ramp signal can be changed. When the system starts, the speed acceleration is smaller than when no integrator is given; 2 the pressure of the platen roller is adjusted and squeezed; 3 the “disturbance” start of the electric drive and the appropriate speed program control; 4 the indirect or the tension Control, etc.

Research on improving the quality of electronic aluminum foil

Figure 1: Aluminum foil rewinding machine

5.2 Composition of the electronic control system

The front bottom roller, the rear bottom roller and the paper ejection roller of the winder are respectively driven by a separate AC motor, and the slitting circular cutter adopts an AC variable frequency transmission, and maintains a 5%–20% speed difference with the rear bottom roller. The auxiliary drive consists of two parts, a pneumatic and hydraulic system, which are used to control the movement of the auxiliary drive mechanism and cooperate with the main drive. The entire electronic control system is mainly composed of three partial volumes, and the chain of the bottom roller is adjusted to be smaller by the town.

5.3 Control of the back roll tension

The control of the rollback tension affects the shape of the finished roll. Stable web tension can avoid lateral deflection of the web. Appropriate web tension can improve the quality of the paper roll to a certain extent, reduce breakage and keep the winder stable. Therefore, web tension control is an important part of the electronic control system.

5.4 Dynamic compensation in the tension control of the eject roller

In the actual operation of the system, the diameter of the ejected paper roll is getting smaller and smaller. Due to the inertia of the system, during the process of accelerating the unwinding, decelerating and stopping and running at a steady speed, the electromagnetic torque of the inertia should be positively added. Moment M. To compensate for the energy that needs to be absorbed.

6 Effect of annealing system on the performance of aluminum foil

Research on improving the quality of electronic aluminum foil

6.1 Effect of thickness on the performance of aluminum foil products

When the metal undergoes cold deformation, the internal energy of the metal will rise, and the atom will be in an unstable state. Naturally, there is a tendency to change in a stable state. Most metal materials refuse to complete this transformation at room temperature, when the metal back is heated, Increasing the mobility of the atom and accelerating the diffusion rate of the atom can complete the transition of the atom to a stable state. This is the internal cause of the fly-off and recrystallization of the cold-deformed metal during annealing. However, the heat energy provided by the cold-deformed metal back is sufficient to overcome the bonding force between the atoms, allowing the atoms to migrate and freely diffuse to occur in the crystallization. The recrystallization temperature depends on the atomic migration to re-form the nucleus and The higher the activation energy required to grow up, the higher the activation energy required and the higher the recrystallization temperature. The first scheme is to carry out intermediate annealing of aluminum foil blank at a thickness of 1.5 mm (cold deformation processing rate is about 80%). The second scheme is to perform intermediate annealing of aluminum foil blank at a thickness of 2.5 mm (cold deformation processing rate is about 65%). The processing rate of the second produced blank is smaller. The activation energy required for recrystallization of the metal is higher, the recrystallization temperature is higher, and the strength is higher. On the other hand, the 2.5 mm intermediate annealed aluminum foil blank is processed into According to the metallurgical theory, the storage energy retained in the dislocation form in the metal structure is the driving force for recrystallization during annealing. The nucleation rate in the recrystallization process increases with the increase of the metal deformation. Therefore, 2.5 is used. Mm intermediate annealed aluminum foil blanks, the aluminum foil obtained by rolling has a greater amount of deformation during annealing, and the storage energy accumulated in the form of dislocations is also larger. The nucleation rate in the original aluminum foil is greatly increased during recrystallization. Therefore, the aluminum foil can obtain a finer grain structure after the finish annealing, and thus the strength and elongation are higher.

6.2 Effect of temperature on the performance of aluminum foil products

For the aluminum foil blank produced by the casting and rolling method, the cooling and solidification and deformation of the metal during casting and rolling are all completed in the casting and rolling zone with a roll diameter of 650 mm – 700 mm. The length of the larger casting zone is about 50 mm. The length of the casting zone is only about ten millimeters. The solidification crystallization of Yuan metal is only about 1 s. The speed of this solidification is about 2 orders of magnitude higher than that of semi-continuous casting. The various impurities and alloying elements in the aluminum alloy are The solid solubility in aluminum varies with temperature. For example, according to the equilibrium phase diagram, the solubility of iron in aluminum at eutectic temperature (655 °C) is about 0.052%. The solubility decreases to 0.002% at room temperature. The faster the cooling rate deviates from the equilibrium state, the more severe it is. Therefore, the intragranular segregation of the billet produced by the casting method and the degree of supersaturation of the solid solution are more serious than those of the semi-continuous casting. If the annealing temperature is high (to reach the homogenization temperature) during the intermediate annealing, the supersaturated element in the metal can be promoted. According to the analysis, the decrease of solid solubility in the phase increases the self-diffusion coefficient of the atom, which is beneficial to the nucleation and growth of the new nucleus during annealing. The recrystallization temperature of the material is reduced. If the temperature does not reach the homogenization effect during the intermediate annealing. However, only the plastic recovery of the metal can be satisfied. At this time, the supersaturated solid solution of the metal is not fully analyzed.

To know which material is better for the power battery casing, the first thing to know is the power battery. Although there is no clear definition of the power battery academic community, the global electric vehicle industry basically agrees that batteries that provide driving power for electric vehicles are called power batteries, including traditional lead-acid batteries, nickel-hydrogen batteries, and emerging lithium-ion power. Lithium batteries are currently being promoted in the world for lightweighting, and aluminum is a better choice. These power battery casings are preferably 3003 aluminum foil.

3003 electronic foil has good formability, mainly used in deep-drawn materials. It uses 3003 aluminum alloy products as stamping parts, models and shells, etc. It has many advantages such as good surface, good plasticity and pressure resistance. The power battery case made of 3003 aluminum alloy product has impact resistance, non-breaking and leakage, and can meet the requirements of strength and rigidity of the power battery case, and the aluminum alloy has small density and light weight, which can reduce the weight of the battery and increase the battery capacity density. To make the battery work stable, indirectly reduce the quality of the vehicle and increase the battery life.

3003 power battery shell is one of the advantages of Mingtai Aluminum, with mature technology, excellent quality and global distribution. The 3003 alloy aluminum coil has the following 4-point performance:

1. Excellent forming and processing characteristics, high corrosion resistance, good weldability and electrical conductivity.

2. The surface is flat, plastic and pressure resistant.

3, with impact resistance, not easy to break and leak, can meet the strength and rigidity requirements of the power battery casing.

4, lightweight automotive aluminum, low density, light weight, can reduce the weight of the vehicle, improve vehicle life.

Scientists love to wrap themselves and everything around them in mystery, and over the past decade, in aluminum foil. Well, no pun intended, not after Paul Feyerabend’s crucifying analysis of the history of science. But it’s the truth. Physicists and other scientists (do we see a dichotomy here?) are literally wrapping important equipment around them in aluminum foil.

Why?

For the sake of advancing science!

Interesting right?

Let’s see how.

Protecting the Atomic Force Microscope from static

We don’t pay heed to the charges that constantly bounce off our cloths as we walk down the street. But when it comes to the world that the atomic force microscope works with, every charge is like a giant boulder of death (or a charged missile) hitting the landscape. Remember that the Intel’s smallest working transistor is just 1 atom thick and 10 atoms wide.

A charge hitting on one is bound to upset bonds and relationships.

So, the charges are unwelcome and need to bounce off. That’s why the research areas and the atomic microscopes are usually wrapped with aluminum foil. It gets rid of the static once it has been properly grounded.  What about the research personal? The people working the labs are de-charged before entering the labs. Then again, you may have seen those shiny silver suits often related to people working with aliens in Area 52. Well, they wear those to protect the equipment more than to protect themselves from alien disease.

We will never know.

Baking Out Accelerating Equipment

Science progresses by falsifying theories. Scientists and engineers create new hypothesis and experiments to verify or falsify them. Given that even the slightest variations in the surrounding can significantly alter the results of the experiment, it becomes important to perform them under highly controlled environments.

That means performing them in vacuum and/or maintaining consistent temperatures across the equipment for optimal results. This is where a cost-effective method called “bake-out” comes into play. It’s simply blanketing and wrapping the aluminum foil around the equipment, securing it with heat tapes.

The SLAC National Accelerator Laboratory as well as the Lawrence Berkeley Lab’s Advanced Light Source uses massive quantities of aluminum foil for their “bake out” maintenance routines. The aluminum foil allows even spread of the heat and aids it in maintaining vacuum throughout the tests. It’s a thing to remember the next time we unwrap our lunch.

Testing X-ray Lasers

Apart from being highly conducive to heat and charge, aluminum is also highly reflective and not to just sunlight. If you have ever forgotten to unwrap a edible wrapped in aluminum foil and placed it in a microwave you may have an idea on how the microwaves get reflected off the foil (to a dangerously awesome light show. Kindly do not try that at home).

Well, the researchers involved in exploring the beginnings of our universe rely on these properties (and others) to recreate almost the exact conditions using aluminum foils. Researchers at the Berkeley Lab, SLAC, and Princeton Plasma Physics Lab, among others regularly direct powerful x-ray lasers towards aluminum foils in to recreate conditions present inside the distant suns and giant stars.

Farming Nano-Crystals for Solar Panels

Renewable energy is one of the best ways of evading total climatic breakdown, and solar energy is one of the most abundant and scantily used resource. The biggest challenge is to create solar cells that can efficiently convert the energy from photons into electrical energy.

Currently one of the biggest challenges is the cell’s ability to absorb and transform as much energy as possible from each photon. Given the speed of light and inefficient transformation capacity, this has posed a problem. Secondly, creating robust solar cells is costly. However, researchers at the Berkeley Researchers published a monumental work in Nature titled, “Three-dimensional nanopillar-array photovoltaics on low-cost and flexible substrates.” The researchers have found a way to develop flexible solar cells by growing the cells on aluminum foil sheets.

The sheets offer a cost-effective and efficient substrate (think farming land) for the crystals! Should we get any ideas for that sandwich? I think it’s highly unlikely that we’ll find them growing there!

Busting Myths about Invasive Radio Signal Protection Hats

This is an indirect advancement because, well, science demythologizes our beliefs (I know Thomas Kuhn and Paul Feyerband won’t acknowledge that) but in a way it does rationalize our actions with empirical research.

We’ve seen those tin foil hats people wear thinking that they will simply bounce off the invasive radio signals present in the atmosphere (both telecommunication radio waves and mind control waves being sent from the stratosphere or aliens). Though we must remain open to possibilities (alien life mostly), researchers at MIT did find that even if such invasive waves existed, the hat would simply amplify them back.

So hats off!

In Conclusion, Aluminum — The Universal Metal

We know the primary properties of aluminum that has allowed it to become the second most mined, smelted, and used metal in the world. It’s inexpensive, lightweight, durable, resistant to corrosion, and works wonders when it is made to work within strong magnetic fields, high temperatures, and to act as an alloy and as an insulator.

So, the next time you are selecting an aluminum foil from the store, remember that researchers committed to unearthing the secrets of the universe, developing renewable technologies, and working with aliens maintain millions of dollars worth of equipment using the unbelievably versatile metallic foil that is aluminum foil.