Atmospheric Corrosion of Metal Coatings

Sliver plated copper, nickel plated copper, aluminum sprayed copper and zinc plated copper were choosed to study the effect of atmospheric environment on metal material corrosion by means of corrosion testing in simulation corrosive gas environments containing H2S, SO2 and NH3, and salt spray testing. The results show that the corrosion of surface coatings on copper substrate caused by ammonia was the most serious and the next were by hydrogen sulfide and sulfur dioxide. The corrosion resistance of four materials in turn is as follows: Al sprayed Cu> Zn plated Cu> Ag plated Cu> Ni plated Cu. Once the coatings on the Cu was corroded, large area corrosion will occur around it, so the destroy by materials transportation and setting must be reduced.