|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Electrode Technology Symposium for Aluminum Production
||Corrosion Behavior of Fe-Ni Alloys as Inert Anodes in Molten KF–AlF3–Al2O3 Salts at 700 °C
||Dao Cao, Zhongning Shi, Xianwei Hu, Bingliang Gao, Zhaowen Wang
|On-Site Speaker (Planned)
The corrosion behavior of Fe-Ni alloys as inert anodes in molten KF–AlF<SUB>3</SUB>–Al<SUB>2</SUB>O<SUB>3</SUB> salts at 700 °C under both polarization and non-polarization were <I>in-situ</I> characterized respectively by utilizing electrochemical impedance spectroscopy (EIS). It was shown that the electrochemical impedance spectrums are composed of two capacitive loops in relation to localized corrosion on the protective scale under both of conditions. Due to the preferential dissolution of Fe from the substrate at the open-circuit-potentials, the formation of Ni-rich scale protects the alloy from corrosion under non-polarization. Moreover, the further dissolution of the protection scale leads the irregular localized corrosion. On the contrast, the oxygen coming from the alumina decomposition is discovered on the electrode surface at high anodic polarization potential, which makes the corrosion products composed of Fe-Ni-O serve as an effective barrier to greatly promote the corrosion resistance. Meanwhile, the dissolution of oxides results in the localized corrosion.
||Planned: Light Metals