Effect of Temperature on Corrosion and Cathodic Protection of X65 Pipeline Steel in 3.5% NaCl Solution

摘要

In this investigation, polarization curve, electrochemical impedance spectroscopy and hydrogenpermeation measurements were used to observe the corrosion behavior and cathodic protection of X65under the influence of temperature. The results show that, with an increase in temperature, Icorr increased.Ecorr decreased and electrochemical impedance decreased, which indicates that corrosion resistance ofX65 steel was weakened. As the temperature was increased, De deceased and c0 increased. The defectsin X65 steel can block the hydrogen diffusion, but the hydrogen concentration in the specimen increased,which increased the risk of hydrogen embrittlement of X65 steel. As the hydrogen charge potential wasshifted negatively, the current density first decreased and then increased, which indicated that theinfluence of hydrogen air masses in X65 is limited.