Liquid metal with solid skin creates printable, stretchable structures

BBC : An alloy of galium and indium developed by Michael Dickey of North Carolina State University in Raleigh and his colleagues is liquid at room temperature but forms a solid skin when exposed to air. The very thin layer of oxidized metal holds its shape, while the interior of the structure remains liquid. Dickey’s team used a printer with a syringe as a nozzle to create free-standing structures out of spherical droplets that maintained their shapes instead of merging. The potential of a liquid metal that can maintain its shape is most evident in the development of flexible electronics. If the alloy is embedded into flexible materials such as rubber, it could be used as a stretchable connection between electronic components. And this new galium–indium alloy also has the benefit of not being toxic like mercury and other liquid metals.