Uniform Corrosion
This is also called general
corrosion. The surface effect produced by most direct chemical attacks
(e.g., as by an acid) is a uniform etching of the metal. On a polished
surface, this type of corrosion is first seen as a general dulling of
the surface and, if allowed to continue, the surface becomes rough and
possibly frosted in appearance. The discoloration or general dulling of
metal created by its exposure to elevated temperatures is not to be
considered as uniform etch corrosion. The use of chemical-resistant
protective coatings or more resistant materials will control these
problems.
While this is the most common
form of corrosion, it is generally of little engineering significance,
because structures will normally become unsightly and attract
maintenance long before they become structurally affected. The
facilities shown in the picuture below show how this corrosion can
progress if control measures are not taken.
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