The corrosion behavior of pure Fe under a Na
2SO
4 deposit in an atmosphere of O
2 + H
2O was investigated at 500 °C by thermo gravimetric, and electrochemical measurements,
viz. potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and
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The corrosion behavior of pure Fe under a Na
2SO
4 deposit in an atmosphere of O
2 + H
2O was investigated at 500 °C by thermo gravimetric, and electrochemical measurements,
viz. potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and surface characterization methods
viz. X-ray diffraction (XRD), and scanning electron microscope (SEM)/energy dispersive spectroscopy(EDS). The results showed that a synergistic effect occurred between Na
2SO
4 and O
2 + H
2O, which significantly accelerated the corrosion rate of the pure Fe. Briefly, NaFeO
2 was formed in addition to the customary Fe oxides; at the same time, H
2SO
4 gas was produced by introduction of water vapor. Subsequently, an electrochemical corrosion reaction occurred due to the existence of Na
2SO
4, NaFeO
2, and H
2O. When this coupled to the chemical corrosion reaction, the progress of the chemical corrosion reaction was promoted and eventually resulted in the acceleration of the corrosion of the pure Fe.
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