Aluminum is a resource-rich white light metal, and the world's aluminum output is second only to steel. Its application in the packaging industry occupies the first place in non-ferrous metals. As a packaging material, aluminum generally uses aluminum plates, aluminum blocks, aluminum foils, and aluminized films. Aluminum plates are usually used as can-making materials or lid-making materials; aluminum blocks are used to make extruded and thinned and deep-drawn cans; aluminum foil is generally used for moisture-proof inner packaging or composite materials and flexible packaging. The packaging plates are all anti-rust aluminum alloys. Manganese and magnesium mainly play the role of increasing the strength of the material and improving the processing performance; copper can also increase the strength of the material, but also reduce the corrosion performance and processing performance; adding zinc, especially in When copper and magnesium are added at the same time, the heat treatment effect will be better, but the corrosion resistance and processability will be reduced; the addition of silicon mainly reduces the melting point of aluminum, improves the strength and melt fluidity, and reduces the thermal expansion coefficient. Aluminum foil is a flexible metal thin material made of industrial pure aluminum sheet with a thickness of 0.4-4.7mm (0.5mm is more commonly used) after multiple cold rolling and thinning.
Application of aluminum materials in packaging
1.Aluminum anti-theft bottle cap
At present, most of the packaging of liquor, wine, medicinal liquor and beverages are still mainly glass bottles. Among them, about 50% of the wine bottle caps are made of aluminum anti-theft caps. Our defense thief caps will increase at a rate of 10% per year. In 2010, the amount of anti-theft covers will reach 15 billion pieces, and about 60,000 tons of aluminum strips will be needed. There are nearly 200 aluminum bottle cap production plants in my country, with an annual design capacity of about 9 billion pieces, of which 30 production lines have been introduced with a production capacity of more than 5 billion pieces, which can produce nearly 100 kinds of bottle caps. Aluminum bottle caps are mostly processed on production lines with a high degree of automation. Therefore, the material strength, elongation and dimensional deviation are strictly required, otherwise cracks or creases will occur during deep drawing. In order to ensure easy printing after the bottle cap is formed, the surface of the bottle cap material is required to be flat without rolling marks, scratches and stains. Generally, the alloy materials used are 8001 to HI4, 3003 to H16, etc. The material specification generally has a thickness of 0.20~43.23mm, an allowable tolerance of ±0.1%, and a width of 449-796mm. The aluminum bottle cap material can be produced by hot rolling or continuous casting and rolling, and cold rolling. Production practice shows that the hot-rolled billet is better than the cast-rolled billet in the use effect of the anti-theft cover.
The information is provided by cheap aluminum sheet supplier.