Since corrosion is a naturally occurring chemical reaction between a metal surface and its environment, there are two obvious ways to prevent it. One is to change the properties of the metal, which can be done by modifying its voltage properties or combining it with other metals (forming an alloy). The other is to change the environment, which is most readily accomplished by depriving it of its flow of oxygen.

Aside from these two standard techniques, there are a few other tacks that metal finishers can take to assist in corrosion prevention. Changing from metal materials to non-metal varieties is the easiest route, though this may not be practical for some applications. It's also possible (and often more feasible) to create inhibitors between the surface material, also known as the cathode, and the corroding element itself, which is known as the anode.

Protecting against Different Forms of Corrosion

Corrosion doesn't come in a one-size-fits-all form. There's bacterial corrosion, which occurs when bacteria spread their waste products to metal parts, as well as stress corrosion, the result of tensile stress that accelerates the chemical reaction, just to name two examples. Longtime coaters are adept at spotting other forms of corrosion as well, such as galvanic corrosion and crevice corrosion.

Regardless of the type of corrosion your parts have suffered, the same general techniques, mentioned above, apply as preventative methods. In a pinch, cathodic protection, which works by substituting a more anodic metal in place of the corroded one, can also work, though it takes some expertise to make this work. Talk to your powder coater about this and other techniques involving electrical currents when it comes time to treat your parts.