Waters from natural sources of the São Miguel Island in the Azores archipelago
have been investigated regarding their corrosive action on metallic materials. The corrosive
and encrusting characteristics of the waters have been established in terms of relevant
chemical parameters (namely pH, conductivity, total dissolved solids (TDS), and
concentrations of bicarbonate, calcium, magnesium, chloride, and sulfate ions) and their
temperature by using Langelier, Ryznar, Puckorius and Larson–Skold indexes. The validity
of this methodology has been tested by measuring the corrosion rates of various metals
exposed to various waters using electrochemical methods. The materials of industrial interest under investigation were carbon and galvanized steel, zinc, 304 and 316L grade
stainless steels, brass, and Cr–Ni alloys. The greater aggressiveness of these waters was
found for the less noble materials, and they experienced high corrosion rates.
