A Kelvin probe force microscopy study of hydrogen insertion and desorption into 2024 aluminum alloy

Manon Chloé Lafouresse (1) , Marie-Laëtitia De Bonfils - Lahovary (1) , Cédric Charvillat (1) , Loïc Oger (1) , Lydia Laffont-Dantras (1) , Christine Blanc (1)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux

Hydrogen was inserted into 2024 aluminum alloy by cathodic polarization in sulfuric acid at 25 °C. Scanning Kelvin Probe Force Microscopy (SKPFM) measurements performed perpendicularly to the charging side revealed a potential gradient and confirmed the insertion of hydrogen over hundreds of microns. A hydrogen diffusion coefficient of 1.7 x 10-9 cm2 s-1 was calculated from SKPFM measurements of H-charged samples for different durations. The evolution of the potential gradient during desorption of hydrogen in air, at room temperature and at 130 °C was investigated. Additional experiments performed at a corrosion defect showed that SKPFM could detect both reversibly and irreversibly bounded hydrogen. These results show that SKPFM is a cutting-edge technique for hydrogen detection and localization at a local scale

Mots clés: Aluminum alloys; Hydrogen absorption; Hydrogen desorption; Atomic Force Microscopy (AFM); Scanning Kelvin Probe Force Microscopy (SKPFM)

Domaines: Matériaux; Science des matériaux [cond-mat.mtrl-sci]; Génie des procédés; Matériaux

Manon Chloé Lafouresse, Marie-Laëtitia De Bonfils - Lahovary, Cédric Charvillat, Loïc Oger, Lydia Laffont-Dantras, et al.. A Kelvin probe force microscopy study of hydrogen insertion and desorption into 2024 aluminum alloy. Journal of Alloys and Compounds, 2017, vol. 722, pp. 760-766. ⟨10.1016/j.jallcom.2017.06.143⟩. ⟨hal-01627635⟩