Unformatted text preview: expected active corrosion rate. The passive film is very fragile and can easily be damaged. If the film can be reformed, then it is protective. For example, aluminum in air is protective and can reform if damaged. It can be "healed". If the aluminum is under a drop of liquid mercury, the passive film cannot be healed and the aluminum reacts with the mercury if damaged. In general, passive films form at high interface potentials. They are characterized by a passivation potential above which, the metal is passive. In the lab demonstration, the passivation of steel in concentrated nitric acid will be examined. Make note of the behavior of the steel in the various environments to which it is exposed. Explain the behavior of steel in: 1. Water 2. Concentrated Nitric Acid 3. 50% mixture of water and concentrated nitric acid 4. Copper sulfate solution...
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- Spring '10
- Aluminium, Oxide, Passivation