Gideon Analytical Labs received a cold rolled steel plate with two corrosion blemishes on the plating. The black corrosion deposition is on zinc plating, which has oxidized with chlorine forming zinc chloride.
The SEM-EDS spectrum shows an excessive amount of chlorine. The chloride is reacting with the zinc. Chlorides are very corrosive to electronic parts, plating, and metals. On copper trace lines the resistance increases, metals discolor, and on aluminum, it acts as a corrosive catalyst causing opens and pitting to metal.
Gideon Labs can identify many contaminants that cause corrosion, high resistance, opens in circuits, solder mask deterioration, polymer destruction, incompatibility issues, etc.
Call us the next time you are having a problem.