Corrosion Science Chemistry Research Article | Page 12

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Corrosion: Understanding the Basics
ported by technology transfer. New and improved corrosion technology
results from research and development. The proper application of meth-
ods to control corrosion (e.g., coatings, inhibitors, and cathodic protec-
tion) reduces the cost of corrosion. The costs of corrosion tend to in-
crease with such factors as deferred maintenance and extended useful
lives of buildings and equipment. Increased corrosion costs are often re-
alized when higher-performance specifications and more hostile envi-
ronments are encountered.
Finally, increased corrosion costs result from government regulations
that prohibit the use of time-honored methods of protection because of
safety or environmental damage. For example, in an effort to reduce
smog, the elimination of lead-based paints on houses and bridges,
chromate inhibiting paints on aircraft, and oil-based paints throughout
industry has had severe repercussions. Substitute water-based paints
have not, in many cases, afforded equivalent corrosion protection.
Cost Elements. Although costs vary in relative significance from indus-
try to industry, several generalized elements combine to make up the total
cost of corrosion. Some are readily recognized; others are less recognizable.
In manufacturing, corrosion costs are incurred in the product develop-
ment cycle in several ways, beginning with the materials, energy, labor,
and technical expertise required to produce a product. For example, a
product can require painting for corrosion protection. A corrosion-
resistant metal can be chosen in place of plain carbon steel, and techni-
cal services can be required to design and install cathodic protection on a
product. Additional heat treatment can be needed to relieve stresses for
protection against stress-corrosion cracking.
Other operating costs are affected by corrosion as well. Corrosion in-
hibitors, for example, often must be added to water treatment systems.
Applied current
technology
More
hostile
environments
Deferred
maintenance
Increased
performance
requirements
Technology
transfer
Corrosion
costs
Extensions
of
useful
life
Environmental
regulations
Research
and
development
Fig. 4 Factors which increase or decrease the costs of corrosion