Salt-Fog Testing

Salt-Fog Testing

Salt-fog testing is a method used to evaluate the corrosion resistance of materials and their effects when exposed to a moist, salty solution. This test, which is in accordance with MIL-STD 810 Method 509, is often used in areas that experience the severe effects of salt fog such as coastal areas. 

The three main results of corrosion are electrochemical reaction-induced corrosion, stress corrosion that is accelerated, and the formation of acidic/alkaline solutions after salt ionization in water. Additionally, salt deposits can cause damage to electrical equipment, manufacture conductive coatings, and corrode metals and insulating materials. Moving parts of mechanical systems or components can also become stuck or clogged, and electrolysis-induced blistering of paint can occur. 

The most commonly tested coatings are zamak, brass, and steel. The salt-fog test is conducted inside a controlled chamber, where salt content, pH, and salt-fog production are all under control. Depending on the distinct characteristics of the coating, different testing methods may be used over various timescales.