Effect on Coating Appearance, Thickness, Materials Handling and Surface Smoothness
Hot dip galvanizing is a functional coating with superior protection from corrosion for steel articles when measured against most other coating systems. The corrosion resistance of hot dip galvanized coatings (ISO 14713i) is directly related to the thickness of the coating (AS/NZS 4680ii).
Certain elements, in particular silicon (Si) and phosphorus (P), in the steel can affect hot dip galvanizing by prolonging the reaction between iron and molten zinc. Generally, this results in the outer pure zinc layer, which is responsible for the shiny metallic finish, being consumed and the dull grey zinc-iron alloys being exposed. In addition, the steel composition can sometimes affect the coating’s resistance to materials handling damage.