Aluminum has a lighter density, higher strength, close to or exceeding steel, and good plasticity. When forming complex products, it is easier to control than stainless steel, with excellent conductivity, thermal conductivity, and corrosion resistance. Currently, the surface treatment processes for aluminum materials, such as anodizing, sandblasting, and power coating, are very mature, and aluminum materials are also widely used in mobile phones. According to the processing method, aluminum alloys can be divided into deformed aluminum alloys and cast aluminum alloys. The grades of aluminum and aluminum alloys are mainly divided into eight series. Alloy grade designation method: International grade (using four numerals, commonly used designation method)