Galvanized wire can be seen as iron wrapped in carbon. When extinguished, the surface layer is more shallow than carbon can contact with oxygen, produce carbon dioxide gas, and radiate the iron wrapped in it. The more carbon galvanized wire contains, the more obvious the phenomenon of spark. The carbon wrapped in iron acts as if it were an explosive in a charge bag, occasionally blowing the iron apart. Sodium and magnesium contain few flammable impurities, and when extinguished, they just glow.
