To monitor paint film degradation and corrosion under the paint film in real time in an atmospheric corrosion environment, we challenged to apply continuous two-point frequency impedance measurement. By using an ICM sensor coated with epoxy resin paint, it was possible to predict the behavior from the growth of paint film defects to the occurrence of rust spots. We confirmed that even if corrosion occurs at the paint film interface, the thick paint film slows down the occurrence of rust spots too. We were able to understand the effects of different corrosive environments, such as constant high humidity and repeated wet and dry conditions, on paint film degradation and corrosion at the paint film interface.

In order to realize a sustainable and safe society, expansion of the use of biomass fuels in coal power plants is considered. Given the elevated concentration of chlorine and heavy metals in biomass fuels, there is a concern that the corrosion effect of these fuels on equipment may be more considerable than that of coal fuels. In this report, we developed a test method to visualize the initial reaction of corrosion by molten salt containing Zn using a glass cell. We attempted to analyze the corrosion mechanism by direct observation of the salt molten behavior using the developed test method and analysis of reaction products after the test.

In this study, the mechanism of the pH decrease of an electrolyte containing ammonium thiocyanate （NH₄SCN） during hydrogen electrolytic charging tests was elucidated. The pH decrease of the electrolyte containing NH₄SCN in the electrolytic charging of hydrogen was caused by the formation of sulfate ions from the oxidative decomposition reaction of thiocyanate ions （SCN^－） on a Pt-based anode.

Furthermore, the suppression effect of an IrO₂-based anode on the pH decrease, having a lower probability to decompose NH₄SCN than a Pt-based anode, was investigated to develop a method for controlling the pH decrease of an NH₄SCN-containing electrolyte during hydrogen electrolytic charging tests. Specifically, using a cation exchange resin-coated IrO₂ electrode, which was found to be highly efficient in oxygen generation, suppressed the pH decrease of the electrolyte as the anode.