What Does Cathodic Blistering Mean?
Cathodic blistering is an experimental approach intended to prevent corrosion in the area of a metal's surface that has been uncovered due to blisters that have burst. Cathodic blistering provides protection through a galvanostatic charge to the uncovered area.
In cathodic blistering, a galvanic reaction occurs at the cathodic side and helps to protect the metal that became inadvertently exposed due to dents and chips when the blisters burst. The cathodic protection is provided to the uppermost coating or paint layer. When blisters subsequently form, a cathodic reaction occurs at the interface, which releases a hydroxyl ion and some positive ions. These hydroxyl ions and positive ions release the osmotic pressure inside the bubble, which splits the thin polymer coating evenly over the exposed area, thereby protecting the areas that became uncovered.