What Is Spangle?

Spangle

In the steel industry, spangle refers to the crystalline pattern that forms on the surface of galvanized steel when it is coated with a layer of zinc. This pattern is a result of the way zinc crystals grow as the steel cools after being dipped in a molten zinc bath during the galvanizing process. The size and appearance of the spangle can vary depending on factors like cooling rate, the composition of the zinc coating, and the conditions in the galvanizing process. Spangle can be desirable for aesthetic purposes, as it gives the steel a shiny, decorative finish. However, for some applications where a smooth, uniform coating is required, spangle may be minimized or eliminated through specific techniques like applying anti-spangle treatments.