采用Tafel极化曲线法和电化学阻抗法研究了690合金在乙醇胺(ETA)和全挥发处理(AVT)两种水工况下的电化学行为, 并着重考察了pH值、温度、Cl-和SO42-对690合金电化学性能的影响. 结果表明, 在两种不同水工况下, pH值升高会提高690合金的耐蚀性, 而温度升高和Cl-, SO42-的加入则均会加速690合金的腐蚀. 在相同条件下, 690合金与ETA水工况有更好的兼容性, ETA的缓蚀性能优于NH3.
The electrochemical corrosion behavior of alloy 690 in environments of ethanolamine (ETA) and all volatile treatment (AVT) water chemistry was studied by means of Tafel polarization curves and electrochemical impedance spectroscopy(EIS) with a particular emphasis on the effect of pH, temperature, Cl- and SO42- on the electrochemical performance of alloy 690. The results showed that under the two different water chemistry conditions, the increase of pH value would enhance the corrosion resistance of the alloy while the elevation of the temperature and the addition Cl- and SO42- would accelerate the corrosion of alloy 690. Under the same conditions, ETA water chemistry environment had a better compatibility with alloy 690 and ETA exhibited better inhibition efficiency than NH3.