Title of article :
Effects of the Different Solid Deposits on the CorrosionBehavior of Pure Fe in Water Vapor at 500°C
Author/Authors :
Li, Ying Institute of Metal Research - Chinese Academy of Sciences - Shenyang, China , Tang, Yanbing Institute of Metal Research - Chinese Academy of Sciences - Shenyang, China , Shen, Xinwang School of Materials Science and Technology - Jiangsu University of Science and Technology - Zhenjiang, China , Liu, Zhihong School of Materials Science and Technology - Jiangsu University of Science and Technology - Zhenjiang, China
Abstract :
A comprehensive corrosion investigation of pure Fe in an environment of solid sodium salt deposit (i.e., NaCl or Na2SO4) withmixtures of H2O and O2at 500°C was conducted by mass gain measurement, X-ray diffraction (XRD), scanning electronmicroscope (SEM), potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The results showed thatcorrosion rates were accelerated with solid NaCl or Na2SO4deposit due to their reaction with the formed protective scale ofFe2O3and subsequently resulted in its breakdown. The corrosion rate of pure Fe with solid NaCl is higher than that with solidNa2SO4because of the lower activation energy (Ea) for chemical reaction of Fe in solid NaCl+H2O+O2(i.e., 140.5 kJ/mol) thanthat in solid Na2SO4+H2O+O2(i.e., 200.9 kJ/mol). Notably, the electrochemical corrosion rate of pure Fe with solid NaCldeposit,1:16 × 10−4A/cm2, was a little lower than that with solid Na2SO4deposit
Keywords :
Different Solid Deposits , Corrosion Behavior , Pure Fe in Water Vapor at 500°C , SEM
