The influence of oxide layers on initial corrosion behavior of copper in air containing water vapor and sulfur dioxide

Abstract To investigate the influence of a surface state on corrosion rates of copper, different surface states of specimens were prepared by different surface finishing methods, and the surfaces under corrosion test in air containing water vapor of 78–83% RH and SO 2 of 16–23 ppm were investigated by in situ IR-RAS. The corrosion rates, especially in the early stage, considerably change depending on the characteristics of the oxide layers: a freshly formed oxide layer with low crystallinity shows a weak inhibition for corrosion, but oxide formed in one day maintains an inhibitive effect for a long time and keeps the corrosion rate very low.