Metals commonly tested using inspection penetrants include aluminum, magnesium, steel, copper, stainless steel, brass, bronze and titanium .
Penetrant testing is portable, inexpensive and relatively quick to perform.
Used in the shot peen process to ensure that no part of the metal has been missed . Very little is required. It creates a thin film which tends to uproot corrosion or contaminants. It bonds itself to the surface of the metal through physical adsorption reducing surface tension. Cleans away rust and contamination.