Atmospheric corrosion of electro-electronics metals in urban desert simulated indoor environment

The corrosion of pure Ag, Cu, Ni, and Sn specimens exposed for 1 to 24 months in a simulated indoor environment, consisting of a rain sheltered atmospheric corrosion test chamber placed in an urban desert environment (Baja California) has been measured. The corrosion rates of the metals were determined by mass loss measurement and the environment was thus classified in the low to medium indoor corrosivity category (IC2–IC3) according to ISO. Silver and copper weight losses were found to be very similar, while the nickel and tin weight losses were several times lower. The silver surface was tarnished in a non-uniform manner, presenting Ag2S and AgCl corrosion products, while the copper specimens corrode uniformly, being covered with Cu2O corrosion product. Owing to the presence of chloride contamination, the nickel and tin oxide corrosion films show fracture and pitting corrosion, developed over the first few months of exposure.