Wetting transition phenomenon in rapidly solidified Al – In alloys

This work presents a continuation of the research carried out on RS Al-In alloys and is aimed to reveal how surface chemistry affects wetting properties of alloys. The Rutherford backscattering spectroscopy (RBS) was used for elemental depth profile analisys of RS Al-In alloys containing from 0.02 up to 5.5 at % In to study the chemical composition in the outermost layers of the surface. It was found that In concentration at the thin surface layer (0,02 μm) of RS foils exceeds manyfold its concentration in the bulk. Revealed degree of In enrichment in the near-surface region is maximal at low concentrations of In in alloys. In addition, the concentration effect of alloying element on the surface contact angle (CA) of distilled water was also investigated. Pronounced wetting transition from the homogeneous Wenzel state to the heterogeneous Cassie-Baxter state is discussed in terms of the penetration of water into the micro/nanostructures of foil surfaces

Morphology and wetting properties of Al-Fe alloy films obtained under conditions of hyperrapid crystallization

The comparative analysis of the surface microstructure and properties of Al-1.5 at.% Fe alloy films on glass substrates prepared by IBAD has been carried out by means of atomic force microscopy, scanning electron microscopy and the sessile drop method .Film deposition in IBAD was performed using a resonance ion source of vacuum arc plasma (vacuum chamber pressure of 10-2 Pa). The rate of "crystallization" (cooling of the cascades) was of the order of 1012-1013 K/s. The analysis of surface properties of the thin films obtained by passive and ion beam-assisted deposition regimes demonstrates the ability to control the structure phase composition and wettability of nanoscale surface structures of Al-Fe alloy films on glass substrates by varying the mode of IBAD

Effect of topography on wettability of rapidly solidified. Al-In alloys

The wettability of rapidly solidified foils of Al-In alloys containing up to 4.7 at.% of In was investigated by means of sessile-drop method and atomic force microscopy. It was found that In significantly changes wetting properties of pure Al from a hydrophobic behaviour to a hydrophilic one. The effect of topography on the wetting properties of nano-rough foils demonstrates that an increase in In content up to 0.7 at.% resulted in a transition from a homogeneous to a heterogeneous wetting behaviour when decreasing the roughness of the surface makes it more hydrophilic

Microstructure, elemental and phase composition and their influence on hydrophilic properties of rapidly solidified Al-In alloys

The microstructure, elemental and phase composition of rapidly solidified foils of Al-In alloys were investigated using SEM with EDX, XRD and RBS. It was found that thin surface layers of foils are enriched with indium that results in hydrophilization of alloys. Wetting transition from the homogeneous Wenzel state to the heterogeneous Cassie-Baxter state observed when indium content increases at the foil surface of hydrophilic Al-In alloys is discussed in terms of the penetration of water into the micro/nanostructures of foil surfaces