Corrosion Behavior of T23 Material Used for Supercritical Water-Wall Tubes in Alkalescent S^2- Solutions

Electrochemical workstation, metallographic microscope, X-ray diffractometer and atomic absorption spectrophotometer were used to study the electrochemical corrosion behavior and corrosion product features of T23 material under the conditions of different values of pH, temperature and S2- concentration. The results show that the corrosion degree of T23 increased with increasing temperature in the temperature range of 10~70 ℃. In the weak base solution S2- attacked the surface of T23 and blocked the OH- inhibitory action. Under the conditions of 70 ℃, pH=9 and 0.1 mol/L S2- solution, Fe2(SO4)3 or the Fe2(SO3)3 was formed on the surface of T23 and Fe3O4 particles were formed on the surface of specimens soaked in the blank solution without S2-.