CORROSION BEHAVIOR FOR WATER WALL TUBE MATER IAL OF 600MW SUPERCRITICAL THERMAL POWER UNITS

摘要

The influence of chloride ions and sulfate ions on 15CrMoG and 12CrlMoVG respectively in the simulated Oxygenated Treatment water chemistry conditions with SO42-and Cl-of different concentrations is studied by using polarization curves,electrochemical impedance spectroscopy (EIS) and high temperature coupon tests.The results show that under the experiment condition of room temperature,the two materials are very prone to corrode in solutions containing SO42-and Cl-and the corrosion rate is enhanced with increasing SO42-and Cl-concentration.The corrosion resistance of 15CrMoG is stronger than 12Crl MoVG for SO42-and Cl-.The corrosivity on 15CrMoG and 12Crl MoVG of SO42-is lower than Cl-.Under high temperature conditions,the corrosion resistance of 15CrMoG stronger than 12CrlMoVG in SO42-solutions.