TY - JOUR A1 - Mundhenk, N. A1 - Huttenloch, P. A1 - Bäßler, Ralph A1 - Kohl, T. A1 - Steger, H. A1 - Zorn, R. T1 - Electrochemical study of the corrosion of different alloys exposed to deaerated 80 °C geothermal brines containing CO2 JF - Corrosion science N2 - Corrosion of metallic engineering materials accounts for problems during geothermal operation in the Upper Rhine Graben (URG). Herein, we study the electrochemical behaviour of various metal alloys in an 80 °C simulated geothermal environment by using potentiodynamic polarisation and open-circuit potential measurements. Two different natural geothermal waters from URG geothermal sites were used for the experiments. The measurements reveal spontaneous passivation to be a key process for all alloys. This ennoblement protects more noble alloys from significant corrosion (e.g. titanium gr. 2, alloy 625) and brings less noble alloys to failure, mostly due to pitting corrosion (e.g. 316L). KW - A. Alloy KW - B. Polarization KW - C. Passivity KW - C. Pitting corrosion KW - C. Repassivation KW - C. Thermodynamic diagrams PY - 2014 DO - https://doi.org/10.1016/j.corsci.2014.03.027 SN - 0010-938X VL - 84 SP - 180 EP - 188 PB - Elsevier Ltd. CY - Orlando, Fla. AN - OPUS4-30634 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -