Complementary Zinc Coatings

摘要

Metallic zinc coatings are well established and recognized as the most cost-effective corrosion protection available for steel structures. Zinc coatings protect steel from atmospheric, marine and in-soil exposure conditions, and can be applied either by hot dip galvanizing or by thermal spraying. Hot dip galvanizing involves the full immersion of the steel into a bath of molten zinc, ensuring complete coverage over all surfaces. However, some structures can be too large to be galvanized. Zinc thermal spray involves projecting drops of liquid zinc onto the surface of the steel using compressed air. With thermal sprayed zinc coatings, there is no size limitation to the part to be coated, and the technology is fully portable, allowing easy field applications. Whether applied by galvanizing or thermal spraying, zinc coatings are fully compatible and steels coated by either method can be incorporated into one structure with no concerns. Zinc coatings provide decades of maintenance free service and case studies of hot dip galvanized and zinc thermal sprayed steel structures will be presented.