Acoustic wave-driven oxide dependant dynamic behavior of liquid metal droplet for inkjet applications

Abstract

In this paper, we report bouncing and separating dynamic behaviors of a liquid metal droplet with/without the oxide layer in response to the applied acoustic wave. When applied the acoustic wave, the oxidized liquid metal droplet is readily bounced off from the surface, while the HCl treated liquid metal droplet is decomposed into several small droplets. We investigated the number of the separated liquid metal droplets for the HCl-treated liquid metal in according to time and acoustic wave amplitude. The bouncing height of the oxidized liquid metal is proportional to the applied acoustic wave amplitude. Finally, we demonstrated the acoustic wave-based inkjet application to generate liquid metal droplets based on the pinch-off and the Rayleigh instability by changing amplitude of the acoustic wave and we also studied the probability for the generation of various droplet sizes with different acoustic wave amplitude.