EFFECTIVENESS OF NICKEL PLATING IN INHIBITING ATMOSPHERIC CORROSION OF COPPER ALLOY CONTACTS

摘要

We performed a series of tests to determine the effect of nickel plating thickness on connector contact resistance. Copper coupons were plated with an electrolytic nickel strike followed by electroless nickel to produce nickel layers with thickness of 10, 20, 55 and 100 μin. The coupons were then exposed to a simulated industrial environment. Pore corrosion was observed after the exposure, and pore densities were found to correlate with nickel thickness. In a second series of tests, beryllium-copper, four-tine contacts with 50 μin of gold plate over electrolytic nickel strike/electroless-nickel plates of varying thickness were exposed to the same corrosive environment. Contact resistance of mated pairs was monitored over a two-month period. The degradation in contact resistance correlated with the nickel thickness used in the contacts.