The following are some examples for corrosion that we experience in our day to day life.

(i) Rusting of iron : Iron exposed to the environment forms a brown rust film on its surface.

(ii) Water stored in aluminium vessel : If water is stored for a long time in an aluminium vessel, white spots will be formed at several places.

(iii) Tarnishing of silver : Silver ornaments are found to form a black, adherent film on their surface.

(iv) Copper vessel : It is found to become dark brown or black in colour.

Need to study corrosion

The average loss of materials due to corrosion in India is INR 300 crores/year. For steel, it has been estimated that 25% of production is lost through corrosion. Hence, an engineer must:

1. be aware of the corrosion problem,
2. understand the mechanism of corrosion and
3. apply his/her knowledge to control corrosion.

[sc_fs_faq html=”true” headline=”h2″ img=”” question=”What is corrosion?” img_alt=”” css_class=””] The process of destruction and consequent loss of a solid metallic material through a chemical or electrochemical attack by its environment is called corrosion. [/sc_fs_faq]

For example : When iron is exposed to atmosphere containing oxygen and water vapour, it is converted into its metallic oxides Fe₂O₃H₂O (Rust).