Environmental Engineering Reference
In-Depth Information
4
Aqueous Corrosion: Prevention
The preventive measures pertaining to each form of corrosion have been pre-
sented in the previous chapter. It is possible to classify the preventive measures
under six general headings:
1.
Materials selection
2.
Control of environment
3.
Protective coatings
4.
Cathodic protection
5.
Anodic protection
6.
Design improvement
Since corrosion involves interaction between material and environment, the
first approach to corrosion prevention is obviously the use of the most compatible
material in a given environment and the next approach is to reduce the aggressive-
ness of the environment toward the material in use. Provision of a coating to
separate the environment from the material in order to prevent their interaction
is also a natural consideration, and many such coatings have been developed and
are being used. Cathodic and anodic protection are preventive measures based
on electrochemical principles of corrosion. Lastly, an improvement in design of
the metallic component or the system to which it belongs can reduce corrosion
in many cases.
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