Wettability of Pure Metals with Liquid Sodium and Liquid Tin

Abstract

This study aims to control the wettability of pure transition metals by liquid sodium or liquid tin. Such wettability was evaluated by measuring the contact angles with the droplet method. Pure titanium, iron, nickel, copper, and molybdenum metals were selected as specimens in this experiment. All experiments were conducted in an environment with high pure argon gas and extremely low moisture to avoid the influence of oxygen on the liquid metals. The measurement temperature was just above the melting temperature of each liquid metal. Results showed that in both liquid sodium and liquid tin, the measured contact angle changed depending on the atomic number of the substrate metal. The electronic structure of the interface between a liquid metal and a substrate metal was calculated by the molecular orbital method. Simple cluster models of the interface between the liquid metal and substrate transition metal were used in this calculation. The calculation results confirmed that the electronic state of the interface was expressed well. The magnitude of the atomic bonding between the liquid metal and substrate metal changed in accordance with the atomic number of the substrate metal, and the magnitude of the atomic bonding between the substrate metals changed similarly. There was an evident relationship between the atomic bonding ratio and the contact angle. The atomic bonding ratio is the ratio of the liquid-metal-substrate metal-atomic bonding to the substrate metal atomic bonding. This finding implies that the atomic bonding affected the wettability between the liquid metal and the substrate metal. The atomic bonding was obtained as one of the indications was obtained to control the wettability by liquid metal.

Electronic Approach to Understanding the Wettability of Sodium-Implanted Metal

“…Theoretical calculations of the interface confirmed no significant change in the atomic interaction at the interface between the on-top and hollow sites of the metal substrate. [2] Therefore, this study performs the calculations at the on-top site.…”

“…The results showed that the contact angle relates to the atomic interactions at the interface. [1][2][3][4] Therefore, we considered that one way to control wettability is to control the electronic state, which is the atomic interaction at the interface. Furthermore, we focused on ion implantation technology to change the electronic state of metal surfaces.…”