Imagine a wire that can stretch eight to 10 times its original length and still send crystal clear audio from your music player to your earphones, or imagine accidentally cutting a cable to a tactical radio and repairing the cut just by physically putting the wires back together.
Those are just two of the many possible products that could result from materials science research now underway at North Carolina State University under the direction of Dr. Michael Dickey, assistant professor of chemical and biomolecular engineering at the university.
Both scientific developments are the result of separate but related avenues of scientific research into advanced materials, explains Dickey, who says much of the work has been conducted by graduate and undergraduate students. “They’re related in the sense that we’ve used some common materials, but they are two different projects,” he says.
“Both ideas are almost embarassingly simple,” Dickey goes on to relate. “What we’ve done is taken the architecture of a conventional wire, which is a metal core surrounded by a plastic casing, and we’ve done two things. We’ve replaced the plastic casing with an elastomeric polymer that’s more like a rubber band, so it's stretchable, and then for the core of the wire, we use a special liquid metal alloy.”
That alloy, made up of gallium and indium, is a liquid at room temperature but has a unique characteristic. “We can shape it because there’s an oxide ‘skin’ that forms on the metal. The best analogy I can use is a waterbed, which, in the absence of a plastic casing, would be a big puddle.”