Carcinogenic chromates are widely used as the most effective corrosion inhibitor. Many key issues about localized corrosion still remain unresolved. Role of Chromate 1. Al is a very active metal, and it depends on its oxide film for passivity. In the presence of aggressive ions, such as Cl - , Al is susceptible to pitting corrosion.
Pitting corrosion is autocatalytic in nature - once it forms, it tends to continue to grow itself.
A schematic of potentiostatic approach 2. 2D Pit - Thin Film Pit Growth Technique 1. A schematic of a 2D pit Al thin film deposited on the inert substrate. When pit forms, it rapidly penetrates the film to the substrate, then grows outwards 2 dimensionally. A schematic of my experimental setup 4.