Corrosion-Resistance Properties of Submarine Cable Steel Armor
Abstract
In this study, the multifactor coupling corrosion mechanism and the effects of different solutions on the corrosion process were explored in detail. The corrosion of submarine cable steel armor is examined based on the evaluation of the steel corrosion resistance. Here, the research object was hot-dip galvanized steel wire—produced using a continuous galvanizing line—which was then subjected to immersion corrosion experiments. Based on the immersion corrosion experiments and CHI660E electrochemical workstation test, the corrosive effects of a solution containing chloride ions (Cl-), sulfate ions (SO42-), bicarbonate ions (HCO3-), and artificial seawater on the hot-dip galvanized steel wire were analyzed in depth. According to the experimental results, the anion species and content influencing corrosion were highest in the artificial seawater. The corrosion rate of the hot-dip galvanized steel wire was fastest in the artificial seawater. However, the corrosion resistance was poor. The corrosion resistance properties of the hot-dip galvanized steel wire in the HCO3- solution were the best. In artificial seawater, the effects of the wire corrosion-resistance properties differed considerably, primarily because of the different ionic characteristics. The degree to which the different ions corroded the wire was SO42- > Cl- > HCO3-. If the salinity increased, the dominant ions influencing corrosion were Cl- ions—that is, the higher the salinity, the higher the chloride-ion content. The corrosion resistance of steel was poor. At the beginning of the corrosion process, the surface zinc in the hot-dip galvanized steel wire generated an oxidation film, which slowed the corrosion rate, improving the corrosion resistance.