Aluminum and aluminum alloy plates and strips
Aluminum and aluminum alloy sheets and strips are important aluminum products with high production volume and wide applications. Made from pure aluminum or aluminum alloys, they are rolled into sheets and strips of varying thicknesses. They offer excellent properties such as light weight, high strength, corrosion resistance, and ease of processing. Pure aluminum sheets and strips possess extremely high electrical and thermal conductivity, making them suitable for electrical and heat dissipation applications. Aluminum alloy sheets and strips are formed by adding alloying elements such as copper, magnesium, silicon, and manganese to form different series of alloys, such as the 2nd series (aluminum-copper alloys), the 5th series (aluminum-magnesium alloys), and the 6th series (aluminum-magnesium-silicon alloys). Each series offers distinct mechanical and processing properties, meeting diverse application needs. The primary difference between sheet and strip lies in thickness and width. Sheets with a thickness greater than 0.2 mm and a wider width are generally referred to as sheet, while strips are thinner and supplied in coils. While the production processes for both are largely similar, strips require higher dimensional accuracy and surface quality.
The production process for aluminum and aluminum alloy sheet and strip primarily involves smelting and casting, hot rolling, cold rolling, annealing, and finishing. This process is complex and requires stringent technical requirements. First, aluminum ingots and alloying elements are placed in a furnace for smelting in proportion to the product’s material requirements. The smelting temperature and time are strictly controlled to ensure uniform alloy composition and remove gases and impurities from the melt. After smelting, ingots are cast through semi-continuous or continuous casting. These ingots undergo homogenization annealing to eliminate internal stresses and compositional segregation, improving processing properties. After milling to remove surface defects, the ingots enter the hot rolling process, where they are rolled into thinner sheets and strips through multiple passes at high temperatures, typically between 350°C and 500°C, depending on the alloy type. The hot-rolled sheets and strips then enter the cold rolling process, where multiple passes further reduce the thickness, improve dimensional accuracy, and enhance surface quality. This cold rolling process can produce work hardening, necessitating intermediate annealing to restore the material’s plasticity. Finally, after annealing, finishing, shearing and other processes, aluminum sheet and strip products that meet the requirements are obtained.
Aluminum and aluminum alloy sheets and strips are widely used in the construction and transportation sectors. In the construction sector, aluminum alloy sheets and strips, due to their excellent corrosion resistance and aesthetic appearance, are used in the production of curtain walls, roofing systems, door and window frames, and other materials. For example, 6-series aluminum alloy sheets, with their excellent weldability and workability, are often used in curtain wall panels. After surface treatments (such as anodizing and spray coating), they not only offer excellent weather resistance but also a variety of colors, enhancing the visual appeal of the building. In the transportation sector, 5-series aluminum alloy strips, with their high strength and corrosion resistance, are used in the production of components such as automotive body panels and floor panels, reducing vehicle weight and improving fuel efficiency. In rail transportation, aluminum alloy sheets and strips are used in train body structures. Their lightweight properties reduce energy consumption, while their impact resistance ensures safe operation.
Aluminum and aluminum alloy sheets and strips also play a significant role in the packaging and electronics sectors. In the packaging industry, pure aluminum sheet and strip, due to its excellent ductility and sealing properties, is used in food and pharmaceutical packaging. Aluminum foil, for example, is an extremely thin aluminum sheet and strip product used to package products like chocolate and cigarettes, effectively blocking oxygen, moisture, and light, extending the shelf life of the product. Aluminum alloy strips, used to make the bodies and lids of cans, offer high strength and ease of forming, meeting the mechanical properties and processing requirements of packaging containers. In the electronics sector, high-purity aluminum sheet and strips, with their excellent electrical and thermal conductivity, are used to make components such as heat sinks and conductive terminals for electronic devices. For example, heat sinks for computer CPUs are often made of pure aluminum sheet, which quickly dissipates heat and ensures stable operation of electronic devices.
With the rapid development of industry and advancements in new materials technology, the production technology and product performance of aluminum and aluminum alloy plates and strips are continuously improving. Manufacturers are developing new alloy materials, such as aluminum-lithium alloys and aluminum-scandium alloys, to further enhance the strength and lightweighting of plates and strips, meeting the demands of high-end sectors such as aerospace. In terms of production processes, high-precision rolling equipment and automated control systems are used to improve the dimensional accuracy and surface quality of plates and strips, while continuous annealing technology is applied to precisely control performance. To meet environmental requirements, companies are continuously improving energy-saving and emission-reduction technologies in the production process, increasing aluminum recovery rates, and promoting green development in the aluminum processing industry. In the future, with the development of industries such as new energy and high-end manufacturing, market demand for aluminum and aluminum alloy plates and strips will continue to grow, and their application areas will continue to expand, providing high-quality material support for the development of various industries.
