Influence of soil moisture on the corrosion processes of carbon steel in artificial soil: Active area and differential aeration cells

Cathodic protection of buried steel structures: Processes occurring at the steel/soil interface during wet/dry cycles

“…This study made use of artificial soil composed of 83 wt.% fine sand particles (SiO 2 , average particle size 22 µm), 14.5 wt.% clay (kaolinite) and 2.5 wt.% peat, already used in previous work . The soil environment used for all the experiments was prepared by incorporating and mixing the electrolyte solution (Table ) and the artificial soil to achieve the desired initial soil moisture level (80% of saturation), leading to an average pH of 7.2 ± 0.1.…”

“…All experiments were performed at room temperature (RT = 21 ± 2°C). A 25 × 30 cm Plexiglass cell, identical to the one designed for previous work, was used to bury two coupons inside the wetted soil, ensuring that they were as far apart from each other as possible.…”

“…Corrosion in soils is a multiscale process: at its core is the electrochemical process at the metal surface, which is highly influenced by film/droplet formation on the metal, the geometry and liquid phase chemistry of such films as well as the development of oxide layers on the metal surface . Soil moisture is generally considered as the most influential parameter because it strongly affects the most crucial point, the transport of O 2 from the atmosphere to the steel surface . This has shifted focus into monitoring and surveying the CP system by determining the residual corrosion rate of the buried carbon steel, which quantifies the CP's effectiveness, under various soil properties.…”

“…The present work follows this series of studies devoted, on the one hand to the corrosion processes of carbon steel in soils occurring during wet/dry cycling and, on the other hand, to the CP of steel structures buried in soils with constant moisture . The idea was to study the behavior of steel coupons buried in soil and subjected to CP during wet/dry cycles.…”

A Novel Approach for the Evaluation of Under Deposit Corrosion in Marine Environments Using Combined Analysis by Electrochemical Impedance Spectroscopy and Electrochemical Noise

“…beneath the areas covered with deposits, the anodic dissolution currents will be intense, whereas the cathodic currents (controlled mainly by the oxygen reduction reaction) will be concentrated typically around the deposited layer at microscopic uncovered areas [59]. As a result of this galvanic effect, UDC will be started, preferably at these crevices, in the form of localized crevice corrosion [4,21,60,61]. As the corrosion proceeds, crevice corrosion reaches the stable stage that is the continuous propagation of the micro-pits that were initiated in earlier stages.…”