In this study, a time-of-wetness (TOW) sensor was fabricated and evaluated according to wet/dry cycle. A thin film electric resistance (TFER) probe war also applied in the same environment for the measurement of corrosion rate. The TOW sensor could not differentiate the wet and dry time, especially in a corrosive environment such as 3.5% NaClsolution. This implies that wet/dry time monitoring by means of TOW sensor requires careful application in various environments. The TFER sensor produced instant atmospheric corrosion rates regardless of environment. The corrosion rate obtained by the TFER sensor could be differentiated according to wet/dry cycle, wet/dry cycle time variation and solution chemistry. Corrosion data from the TFER sensor showed that corrosion could proceed even after a wet cycle because of retained electrolyte at the surface.
KEYWORDS: atmospheric corrosion, time-of-wetness, electric resistance probe, corrosion rate