Corrosion Mechanism

* Corrosion in an electrochemical reaction
* An Electrochemical cell contains four main components:
1. Electrolyte
2. Anode
3. Cathode
4. External Circuit

ELECTROCHEMICAL CELL
Fe ---->Fe++ + 2e- (1)
O2 + 2H2O + 4e- ----> 4OH- (2)
2H2O + 2e- ----> H2 + 2OH- (3)

what is corrosion??

The deterioration or degradation of materials, usually metals because of the environment

& why do metal corrode?

* Most metal used in construction are subject to corrosion.

* This is due to high energy content of the elements in metallic form.

* In nature, most metals are found in chemical combination with other elements.

* Which later change into metals or alloys by introduction of energy.