Texture and Corrosion Property in the Hopeite Crystal Coated Steel

Potential dynamic polarization test, salt spray test(SST) and humidity cabinet test were carried out with 2∼3μm thin film hopeite [Zn 3 (PO 4 ) 2 .4H 2 O] crystals coated on electrogalvanized strip. The results showed the better properties in tri-cation type hopeite crystals coated steel. The texture of the hopeite layer by bi-cation can be described with one fiber component, but the texture by tri-cation consists of the stronger four fiber components. That would mean the addition of Mn causes the higher intensity of texture and components, and they promote the better resistance of corrosion and chemical stability.