Researchers at North Carolina State University have come up with a really interesting innovation with electric wires. It can both stretch and, when severed, heal itself. The wires are made of a liquid-metal core and a polymer sheath that "reconnect at the molecular level" when damaged, making them great for lowering the need for maintenance for wires placed in high-stress environments.
NCSU reports, "The researchers first created tiny tunnels, called microfluidic channels, in a commercially available self-healing polymer using solid wire. By filling those channels with a liquid-metal alloy of indium and gallium, they were able to create a liquid-metal wire in an elastic sheath. Because the wire is liquid, it can be stretched along with the polymer sheath."
A stretchable wire in itself is pretty amazing, but even more so is the ability to repair itself. When severed, the liquid metal oxidizes which creates a skin to keep it from leaking out of the polymer sheath. Think of it in the same way the blood clots to create a scab so we don't bleed to death when we're cut. Then, when severed edges are placed back together, the liquid metal reconnects itself. Check it out in the video above.
Gizmag writes that not only is this great for wires in high-stress environments but it also allows a new flexibility in creating circuits: "Additionally, circuits could be created or rewired using nothing more than a pair of scissors. It’s also been suggested that multiple pieces of the liquid metal-carrying polymer could be joined together end-to-end, to create three-dimensional conductive structures."