Corrosion analysis of copper T2 exposed to polluted atmospheres and study on prediction model

Abstract

AbstractThe power supply accident caused by the corrosion of metal materials in the substation has become an important issue that affects the safe operation of the power grid. The corrosion of copper T2 was the most serious. The corrosion behaviour of copper T2 in SO2- and H2S-containing atmospheric environments was investigated using electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), and X-ray diffraction (XRD), and the nonequidistant grey GM(1,1) model was established of which the precision and forecast dependability were evaluated. Results indicated that the corrosion rate of copper in the SO2 environment increased in the early stages of corrosion and then gradually decreased at the later stages. In contrast, the corrosion rate of copper in the H2S environment slowly increased in the early stages of corrosion and then sharply increased at the later stages. The corrosion products in the SO2 environment consisted of cuprite (Cu2O) and brochantite [Cu4(OH)6SO4], whereas the corrosion products in the H2S environment were Cu2O and chalcocite (Cu2S). The mathematical model has good prediction dependability and higher forecast reliability.