4 - Contribution of iron archaeological artefacts to the estimation of average corrosion rates and the long-term corrosion mechanisms of low-carbon steel buried in soil

International audienceThis chapter provides an overview of contribution of iron archaeological artefacts to the estimation of average corrosion rates and the long-term corrosion mechanisms of low-carbon steel buried in soil. It presents a review of some previous studies dealing with the corrosion of low-carbon steel in specific conditions and of ancient iron artefacts. It proposes a methodology to study archaeological analogues. It discusses the characterization of the corrosion layers formed on the archaeological artefacts using specific techniques and proposes the corrosion mechanisms for the main observed layers. The chapter also focuses on the determination of the average Corrosion Rates (CR) on the archaeological artefacts. The method proposed to evaluate the corrosion rates is based on the quantification of all the oxidized iron around the artefacts. The validity of the corrosion rates evaluated by this method is discussed in the chapter using thermodynamic solubility calculations on the oxides constituting the corrosion layers