The corrosion behaviors of super 13Cr tubing steels were investigated by immersion corrosion test in NaCl solution from 20 ℃ to 80 ℃. The corrosion rate, corrosion morphologies, corrosion products and electric characteristics of surface films were analyzed by scanning electron microscopy (SEM), energy dispersive analysis (EDS), Xray Diffraction (XRD), weight loss, polarization and electrochemical impedance spectroscopy (EIS). The results shows that super 13Cr tubing steels has better general corrosion resistance properties in NaCl solution under 80 ℃, and the surface films has passive characteristics. The temperature of solution has influences on the corrosion of super 13Cr tubing steels in NaCl solutions in a certain degree. With increasing temperature, the corrosion resistance properties of super 13Cr tubing steels decrease, while the tendency of corrosion increases. The protection properties of passive films decrease for the substrate, which are significant with the solution above 60 ℃. The localized corrosion of super 13Cr tubing steels is caused by pitting in NaCl solution at different temperatures, and then results in general corrosion. The corrosion products consist of Fe and Cr oxides, which are incompact.
YAO Xiaofei, XIE Faqin, WU Xiangqing, WANG Yifei.
Films Electrochemical Characteristic and Corrosion Behaviors of Super 13Cr Tubing Steels in NaCl Solution at Different Temperature[J]. China Surface Engineering, 2012, 25(5): 73-78