Corrosion is a process by which a material may gradually wear away, usually by a chemical action. Metal corrosion is a natural oxidative process that results in an undesirable outcome, i.e., rust. Examples are common – from marine, structural and architectural applications, to residential fencing and automobiles. We are continually exposed to its impact, from superficial to severe.
The cost of poor corrosion resistance is dramatic, as determined in a 2002 study by the U.S. Federal Highway Administration. As shown in Figure 1, the study determined the estimated direct cost of corrosion in the United States to be a staggering $276 billion, or approximately 3.1% of the nation’s gross domestic product. The transportation and utilities sectors received the greatest impact.