by Don George, Charles Howell with Michigan Metal Coatings Company
Quite often when discussing corrosion protection, the question of Neutral Salt Spray (NSS) vs. Cyclic Corrosion Testing (CCT) comes up. Why do OEMs (Original Equipment Manufacturers) require these tests? What are these tests and how do the two methods differ? Perhaps this article will add a little clarity to the subject and give you a better understanding of what they are, what they do and why we use them.
To answer these questions, we really have to first ask, “What is corrosion?” In this article we will be directing our comments on corrosion of steel and iron parts only. Corrosion (commonly known as rusting) is a natural and gradual breakdown of metals due to a chemical reaction that occurs when the metal is exposed to an external environment. The external factors that cause metals to corrode can be water, acids, salts, automotive fluids and others.