abstract
The objective of this work is to investigate the scale of the effect of spontaneous solution evaporation during SVET (Scanning Vibrating Electrode Technique) measurements and demonstrate how it biases the final results. When SVET maps are continuously acquired for more than several hours, the measured currents are smaller than expected. This is attributed to solvent (typically water) evaporation which leads to an increase in solution conductivity over time. If this is not considered when converting the measured potential differences into the local current densities, the SVET results display currents smaller than the true ones. Here, this effect is studied with a platinum disk electrode as source of a constant current and a model corroding system consisting of the AA2024/CFRP galvanic couple. Corrective actions are proposed to mitigate the problem, either in the experimental set-up or as numerical correction.
keywords
SCANNING VIBRATING ELECTRODE; LOCALIZED CORROSION; PROTECTIVE-COATINGS; ALUMINUM; PERFORMANCE; MECHANISM; DEFECT; STEEL
subject category
Chemistry; Electrochemistry
authors
Bouali, AC; Bastos, AC; Lamaka, SV; Serdechnova, M; Ferreira, MGS; Zheludkevich, ML
our authors
António Alexandre Cunha Bastos
Assistant Researcher
Maria Serdechnova
Post-doc Fellowship
Mário Guerreiro Silva Ferreira
Retired ProfessorProjects
MULTI-functional metallic SURFaces via active Layered Double Hydroxide treatments (MULTISURF)
CICECO - Aveiro Institute of Materials (UID/CTM/50011/2019)
PROAIR - Active PROtection of multi-material assemblies for AIRcrafts (PROAIR)
acknowledgements
This work was realized thanks to a partial financial support from European FP7 project PROAIR (PIAPP-GA-2013-612415) and Horizon 2020 project MULTI-SURF (Marie Sklodowska-Curie grant agreement No 645676). This work was also developed within the scope of the project CICECO-Aveiro Institute of Materials, FCT Ref. UID/CTM/50011/2019, financed by Portuguese national funds through the FCT/MCTES.