Dynamic measurements and wettability phenomena in mesoporous anodic films prepared on 1050 and 2024T3 aluminium alloys

• Published in: Microporous and mesoporous materials 2016-11, Vol.235, p.32-41
• Main Authors: Giffard, Kévin, Arurault, Laurent, Blanc, Christine
• Format: Article
• Language: English
• Subjects: Aluminium alloy; Anodic film; Engineering Sciences; Materials; Mesoporosity; Tortuosity; Wettability
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2016.07.042

The wettability of mesoporous anodic films has until now been a parameter rarely studied although it remains crucial especially for sealing treatment following anodising. Wettability measurement is in fact complex as it depends on a number of process parameters relating to the three phases (mesoporous anodic film, deposited liquid and ambient gas). In the present study, an innovative experimental approach was first adopted involving measuring the characteristics of a deposited water drop (contact angle, chord length and height of the drop) in relation to time. Following this, a flow balance allowed the amount of water having infiltrated the mesopores to be determined for two types of anodic film, one tortuous (on an AA 2024T3 substrate), the other not (on an AA 1050 substrate). On the basis of models already available in the literature, a phenomenological mechanism (spreading, penetration and evaporation) was finally proposed and discussed especially with respect to the tortuosity and prior drying of mesoporous anodic films. [Display omitted] •A new dynamic wettability measurement technique was developed.•Changes in contact angle on mesoporous anodic films were studied.•Results showed the decisive influence of tortuosity of the mesoporous anodic film.•Results highlighted the successive phenomena of spreading, infiltration and evaporation of the solvent.