Abstract : The preservation of archaeological iron artefacts necessitates stabilization treatments. For this study, such treatments were applied, in aerated and deaerated NaOH solutions, to Roman iron bars excavated from a marine site in order to understand the evolution of corrosion layers composed of ferrous hydroxychloride β-Fe2(OH)3Cl. Their transformation was monitored in situ by micro-diffraction under synchrotron radiation and characterized ex situ using multi-scale complementary analytical tools. The formation of transient phases such as ferrous hydroxide Fe(OH)2 was identified in both media and chlorinated green rust GR(Cl−) occurred in aerated solutions, showing the influence of dissolved oxygen on the transformation processes.
