ICM sensor consisting of three spiral-shaped electrodes was used to monitor the galvanic corrosion of a combination of three metals, iron, zinc, and aluminum in wet-dry cyclic condition. Zinc is anodically dissolved against iron as a sacrificial protection. In the case of NaCl, Al was less noble than Zn, but in the case of artificial sea salt, Al was more noble than Zn and hardly contributed to the sacrificial corrosion protection of Fe. The dissolution current of Al was larger in the wet-dry cycle than in the immersion.
In Japan, ammonia is expected to be used as a fuel, but stress corrosion cracking (SCC) can be a problem in large low-temperature storage tanks, which are necessary for a stable fuel supply. In order to search for materials with high strength and low SCC susceptibility, we developed a SCC test equipment that can be tested in low-temperature liquid ammonia and a test method that can reproduce SCC initiation in carbon steels in a short period of time. In addition, stainless steels SUS304 and SUS821L1 were also investigated for SCC susceptibility using the developed test method.