Galvanized steel usually stands up well to water exposure—as long as it’s not salt water. Stainless steel, on the other hand, is made by adding chromium to molten steel. Because of its strength and resistance to rust, stainless is the primary metal used in construction.
Hot-dip galvanized steel resists corrosion in numerous environments extremely well. It is not uncommon for galvanized steel to last more than 70 years under certain conditions. To get a good idea of how long your project will last, see the service-life chart.
Hot-dip galvanizing is a process of applying a protective zinc coating by dipping product in bath of molten zinc. … Zinc plating or electroplating is a process where zinc is applied by using a current of electricity. It is a thinner coating than hot dip galvanizing making it unsuitable for outdoor applications.
Stainless steels, for example AISI 304 or so called acid-proof stainless steels, AISI 316, are sometimes galvanized when stainless parts are welded onto carbon steel. The zinc coating on the stainless parts may be thick with a dull surface finish, depending on the content of silicon, chromium and nickel.
Another common exposure for hot-dip galvanized steel is partially or fully buried in soil. … Even in very close proximity, soil conditions can have significant variations. The main factors that dictate the corrosivity of the soil are moisture content, pH level, and chlorides.