Researchers from North Carolina State University filled a syringe with an alloy of the metals gallium and indium. The combination forms a thin skin when it's exposed to air, while retaining a liquid interior state. The effect is a malleable, “stretchable” metal that’s ideal for 3-D printing.
“The metal forms a very thin layer of oxide and because of it, you can actually shape it into interesting shapes that would not be possible with normal liquids like water," lead researcher Michael Dickey told BBC News.
Other metals that are liquid at room temperature, such as mercury, are highly toxic and therefore impractical for 3-D printing. But Dickey explained that the gallium-indium alloy is perfectly safe.
The ability to print circuit components and bendable electronics is one of the main applications for the technology, but some developers are more excited about its “wearability.” The fact that the alloy can be stretched makes it ideal for “smart clothing”—attire integrated with tiny electronics that may one day be able to automatically sew fibers, broadcast advertising signals, or even read vital signs. You know, like Minority Report.
In its current form, smart clothing is unfashionable to the point of being offensive. But if the electronics can be stretched out and made nearly invisible, it might not be such a silly concept.
So 3-D liquid-metal could start becoming common—even if right now, the alloy costs 100 times that of 3-D printing plastic.