A New Measurement and Evaluation of Wettability between Solid and Liquid Metals in Ultra-High Vacuum (2nd Report)

Experimental Examination of Wettability and Atomic Diffusion

Abstract

This paper presents experimental results of the wettability and atomic diffusibility of liquid metals on clean solid surfaces. Six types of liquid metals; Au, Ag, Cu, Al, Fe, Ti, and three types of substrates; tungsten, glass-like carbon, highly oriented pyrolytic graphite (HOPG), are used as the specimens. Contact angles of liquid metals are measured with good reproducibility using a continuous Ar sputter cleaning process as is introduced in the previous paper. Interaction energies of these systems are obtained. As liquid Fe has different diffusibility for two carbon substrates, glass-like carbon and HOPG substrates, atomic concentrations of the substrate surfaces are investigated using scanning Auger electron spectroscopy. Consequently, it is found that liquid Fe has atomic diffusibility with a glass-like carbon surface but not with HOPG (001) surface.