Introduction to Corrosion Lecture#01

2 Definition Corrosion may be defined as the destruction of a metal or an alloy because of chemical or electrochemical reaction with its surrounding environment or medium a metal or an alloy environment or medium

3 Environments in Corrosion 1 1 Sheir, L.L., R.A. Jarman, and G.T. Burstein, eds. Corrosion. 3rd ed. Vol , Butterworth-Heinemann: Oxford.

4 Corrosion: Metallurgy in Reverse 2 2 Fontana, M.G., Corrosion Engineering. 3rd ed. 1986, New York: McGraw-Hill.

Some Corrosion Failure Examples 3 3 Corrosion Doctors Website. Homepage:

6 Aloha Incident

7 Aloha Incident (Contd..)

8 Bhopal Accident

9 Carlsbad Pipeline Explosion

10 Flow Accelerated Corrosion

11 Nuclear Reactor with a Hole in the Head

12 Losses due to Corrosion 4 4 Uhlig, H.H. and R.W. Revie, Corrosion and Corrosion Control. 3rd ed. 1985, New York: John Wiley & Sons.

13 Cost of Corrosion Which cost more?  Corrosion  Fire  Flooding  Earthquake

14 Cost of Corrosion(2004) in billion US$ 5 CountryDirect CostIndirect Cost USA (approximately) Japan59.02 Former USSR55.01 Germany49.26 UK8.51 Australia7.32 Belgium6.75 India3.78 Poland3.53 Canada Global (approximately) 5 Bhaskaran, R., N. Palaniswamy, and N.S. Rengaswamy, Global Cost of Corrosion—A Historical Review, in Corrosion: Materials, Vol 13B, ASM Handbook. 2005, ASM International.

15 Example of Overdesign 3 An 8" in. dia oil pipeline 225 miles long with a in. wall thickness was installed with no corrosion protection system With appropriate protection namely cathodic protection, it would have a thin wall thickness which would  save 3,700 tons of steel (worth more than one million dollar)  increase internal capacity of the pipeline by about 5%.

16 So……Why Study Corrosion? Materials are precious resources Engineering design is incomplete without knowledge of corrosion Applying knowledge of corrosion protection can minimize disasters Corrosion – contaminate products such as pharmaceutical, food and dairy products or luxury items like soap Corrosion products – threat to the environment Artificial implants for the human body!!!

17 Distribution of disciplines in which active corrosion engineers have graduated

18 So.. What would be expected from You (a Corrosion Engineer)? Ensuring maximum life of new equipment Preservation of existing equipment Protecting or improving the quality of a product in order to maintain or improve a competitive position. Avoiding costly interruptions of production. Reducing or eliminating losses of valuable products by spillage or leaks. Refitting of equipment withdrawn from service because of corrosion. Reducing hazards to life and property that might be associated with corrosion:  Explosions of pressure vessels or piping systems  release of poisonous or explosive gases or vapors are a few examples.