My customer is getting white rust on stored parts despite careful packing. What is the answer?
White rust is evidence that corrosion has occurred, usually in a moist environment with either acid or alkali materials present. Obviously, die-castings should be dry before being stored but a common cause is “sweating” or condensation, which occurs when the temperature changes suddenly. The use of paper or cardboard packaging greatly increases the effect since these materials contain acid and they hold the moisture in too. Open wire mesh containers with plastic separators work best by allowing circulation of air around the parts. The use of “de-watering” solutions or vapor phase inhibitor wrappings is also recommended.
