Question

In protection of metals from corrossion, explain why the anodic portion alone should never be painted or coated.

Answer 1

Answer:

The layer of paint prevents the water and oxygen necessary for rust formation from coming into contact with the iron. As long as the paint remains intact, the iron is protected from corrosion

Explanation:

Answer 2

In protection of metals from corrosion, the anodic portion alone should never be painted or coated because of the following reasons:

• There is nothing like a perfect coating.
• The anodic portion in coatings alone is not able to prevent corrosion of the metal underneath.  
• There will be defects like microscopic pores even in an excellent coating that allows air/water that initiates the corrosion process.