Mirror polished 4 x 8 aluminum sheet is processed by rolling, polishing and other methods to make the surface appear mirror-like.
There are many types of aluminum lenses, ranging from low to high, including ordinary polished aluminum, mirror anodized aluminum, and super-mirror aluminum.
Common polished aluminum sheet is usually 86% reflectivity, generally used in some relatively low decoration, but the decorative effect is still very good. Mirror anodized sheet and super-mirror aluminum usually have 95% reflectivity and are used for high-end decoration. It also has applications in some high-end electronic products and high-tech research.
As an ordinary buyer, how to test the quality of aluminum lenses? After tearing off the protective film, touch the mirror surface with your fingers, the sweat stains on your fingers will remain on the mirror surface, but after wiping with a dry cloth or paper towel, the fingerprints will be wiped clean without leaving traces. This is a high quality mirror anodized aluminum plate.
For ordinary polished aluminum, the fingerprints left behind cannot be removed, and they will become more and more dirty as they are wiped.
Another way to test is to put a small Quality Alloy Aluminum Sheet over your ear and let it flex quickly. If you can hear a slight tearing sound, it's a mirror-anodized aluminum sheet. Because the surface of the mirror anodized sheet has an oxide film similar to corundum, because the aluminum itself has a different structure from the oxide film, the oxide film will burst and make a slight tearing sound during the bending process.