6533b7dbfe1ef96bd1270cd9
RESEARCH PRODUCT
Local electrochemical impedance spectroscopy study of the influence of ageing in air and laser shock processing on the micro-electrochemical behaviour of AA2050-T8 aluminium alloy
Patrice PeyreH. AmarVincent VignalHalina Krawiecsubject
Materials scienceMatériaux [Sciences de l'ingénieur]Scanning electron microscope020209 energyGeneral Chemical EngineeringAnalytical chemistryOxidePolishing02 engineering and technology021001 nanoscience & nanotechnologyMicrostructureDielectric spectroscopy[SPI.MAT]Engineering Sciences [physics]/MaterialsStress (mechanics)chemistry.chemical_compoundchemistryvisual_art0202 electrical engineering electronic engineering information engineeringElectrochemistryAluminium alloyvisual_art.visual_art_mediumAluminium alloy - Capillary techniques - Corrosion - EIS - Microstructure0210 nano-technologySpectroscopydescription
International audience; In the present paper, the micro-electrochemical behaviour of AA2050-T8 in 0.1 M NaCl was first studied after polishing by means of local electrochemical impedance spectroscopy and field-emission scanning electron microscopy/electron dispersive spectroscopy (FE-SEM/EDS). The influence of ageing in air and LSP was then investigated. Ageing in air for three months led to an increase in the charge transfer resistance. This was clearly observed in sites surrounding constituent particles where the charge transfer resistance was in the order of 1 MΩ cm2 (instead of 10-3 MΩ cm2 after polishing). Increased passivity around particles was confirmed from FE-SEM/EDS analysis. On the other hand, the effect of LSP on the behaviour of the matrix was found to be extremely beneficial. Both charge transfer and oxide film resistances were sharply increased to approximately 0.35 MΩ cm 2 and 1 MΩ cm2, respectively, as opposed to approximately 1.9 × 10-3 MΩ cm2 and 4.2 × 10-3 MΩ cm2, respectively, after ageing in air. This was attributed to the presence of compressive stresses at the specimen surface after LSP treatment. Stress values were determined from XRD measurements.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-11-01 |