US military researchers have developed liquid metal systems that can autonomously change their structure when strained or stretched – in what looks like one more step toward the evil shape-shifting robot from Terminator 2: Judgment Day.
According to a press release by the US Air Force Research Laboratory, the new material is called Polymerised Liquid Metal Networks. It consists of self-organised nanostructures, which are built from individual particles of liquid metal enclosed in shells that are connected one by one into a network through a polymerisation process.
These networks can be strained up to 700 percent, and can autonomously respond to the strain and still return to their original state, scientists say. Each stretching cycle after the first saw the conductivity increase and then return to normal; the material reportedly preserved the property after 10,000 cycles.
“This response to stretching is the exact opposite of what you would expect”, said Dr Christopher Tabor, the lead research scientist.
“Typically a material will increase in resistance as it is stretched simply because the current has to pass through more material. Experimenting with these liquid metal systems and seeing the opposite response was completely unexpected and frankly unbelievable until we understood what was going on”.
The properties of this material may be applied in the next-generation of wearable electronics or as stretchable antennas.
“The discovery of Polymerised Liquid Metal Networks is ideal for stretchable power delivery, sensing and circuitry”, said Capt. Carl Thrasher, a research chemist at the lab. “Human interfacing systems will be able to operate continuously, weigh less, and deliver more power with this technology”.
Earlier this year, Chinese scientists figured out how to create a liquid metal that can stretch out and move both horizontally and vertically without breaking apart.