Capillary Flow of Gallium Based Liquid Metal with Surface Oxide*

Gallium-based liquid metals are attracting growing interest thanks to their potential applications in flexible electronic devices. The liquid metals are non-toxic and highly electrically conductive while the state of liquid at a room temperature allows exclusively large deformations. The liquid metals typically form a surface oxide layer in the atmosphere leading to solid-like behavior, and their flow often exhibits unpredictable and complex characteristics. To better understand the effects of the oxide layer of gallium-based liquid metals on flow, we experimentally investigate liquid metal flow in a capillary tube and analyze the forces acting on the interface with the oxide skin.