Corrosion Behavior of Brass H62 in Harsh Marine Atmosphere in Nansha Islands, China

Abstract

The corrosion behavior of brass H62 exposed to the atmosphere of Nansha Islands for 21 months was investigated by weight loss, scanning electron microscopy, x-ray diffraction and electrochemical techniques. The results showed that the average corrosion rate of brass H62 exposed for 1 year was approximately 13.47 g m−2 a−1, and the corrosion products were observed to be unevenly distributed, attributed to the dezincification corrosion. In addition to the zinc-containing compounds Zn5(OH)8Cl2·H2O and NaZn4(SO4)Cl(OH)6·6H2O, the copper-containing compounds Cu2O and Cu2Cl(OH)3 were also detected on the front side of the exposed sample, while only the zinc-containing compounds were detected on the back side. Both sides of brass H62 showed a decreasing corrosion rate, but the corrosion product layer on the back side appeared to be more protective for the same exposure time.