Applicability of ToF-SIMS and stable oxygen isotopes in KCl-induced corrosion studies at high temperatures

ToF-SIMS proved to be an applicable tool in high-temperature corrosion studies, in this case, providing detailed information about the distribution of the two oxygen isotopes at the sample surfaces. Oxygen from air prefers to form a solid intermediate, potassium chromate (K2CrO4), when reacting with a chromia-forming alloy, whereas oxygen from both sources was found in the oxide formed at the alloy surface. Regardless of the prevailing conditions, the nickel-based austenitic alloy withstood corrosion the best, then the iron-based high alloy austenitic steel, whereas the low alloy ferritic steel had the poorest corrosion resistance ability.