ID 50

Study of Galinstan Liquid Metal Breakup using Backlit Imaging and Digital In-line Holography

 

Abstract:

Many liquid metals form surface oxides, which can affect atomization processes during thermal spray coating and metal powder formation. In this work, we experimentally investigate the behaviors and morphologies of a liquid metal under a shockwave-induced cross-flow. Specifically, we use Galinstan, a non-toxic room temperature liquid metal that forms thin elastic oxide layers. By utilizing backlit imaging and digital in-line holography (DIH) of liquid columns inside a shock tube, we are able to compare the behavior of Galinstan with water. Morphological differences and drag properties are investigated as a function of Weber number in the bag, multimode, and sheet thinning regimes. We show that surface oxides appear to drive liquid metal Galinstan to break up earlier in non-dimensional time and cause the formation of more non-spherical breakup shapes and droplets. This investigation of surface oxide behaviors helps to further the understanding of liquid metal breakup.