Microscopically, this honeycomb structure consists of aluminum units containing zinc. While the galvanized coating provides anodic protection, the reduced zinc content and aluminum wrap make it less susceptible to electrolysis. However, this also means that the galvanized sheet loses its protection when cut, causing rust on the cut edges.
To solve this problem, it is recommended to protect the edges with paint or zinc-rich varnish, thus prolonging the life of the board. This protective layer protects the galvalume steel, ensuring its service life and maintaining its excellent corrosion resistance even under the harshest atmospheric conditions.