The concentration of nitrogen dioxide, a major air pollutant, is increasing. If it continues, it may be the cause of increased corrosion dangers in metals. In those dangers, stress corrosion cracking (SCC) could be a serious possible corrosion problem. Thus the evaluation of SCC susceptibility on AISI 1018 carbon steel, one popular steel, under low NO 2air aqueous system was the focus of this investigation.
1018 steel was exposed to standard corrosive water with or without NO 2at room temperature. The SCC was examined using a step-stress technique and a potentiostat machine. No SCC was microscopically observed. Other results showed the potentio-dynamic polarization curves and indicated that corrosion rates were increased when the concentration of NO 2was increased. Since some pits and corrosion scars on specimens were observed during the experiments, there is a need to investigate SCC at the condition of a longer test period.