Researchers have developed a self-healing material that could help machines repair themselves – even after "extreme mechanical damage." Not only does the material make physical repairs, but in doing so it can restore severed electrical connections: a potentially huge benefit to machines and robots in hazardous environments. If self-repairing machines sound like something out of the Terminator films, you may be closer to the mark than you think ... the breakthrough depends upon liquid metal.
Or liquid metal droplets, to be precise – suspended in an elastomer (or bendy silicone, essentially.) When this composite material takes damage, the droplets burst, letting them make new connections with other nearby droplets. The droplets are made of a gallium-based alloy, which can carry a rerouted electrical signal without interruption, the researchers claim. The material can reroute power or data in the face of cuts, punctures or even missing material.
"If we want to build machines that are more compatible with the human body and the natural environment, we have to start with new types of materials," research author Carmel Majidi says in a press release. Majidi argues that other research into "soft electronics" that has focused on bendable materials is still prone to failure when damaged. "The unprecedented level of functionality of our self-healing material can enable soft-matter electronics and machines to exhibit the extraordinary resilience of soft biological tissue and organisms."
Possible uses are much as you'd imagine: robots, or anywhere that power or data transmission infrastructure might be at risk. Less dramatic, but perhaps equally useful, the research shows that the material sustains conductivity when stretched – which could prove useful for wearable technology. The researchers also mention inflatable technologies as another possibility.
This research adds to the field of self-healing materials. We've previously seen self-healing membranes for fuel cells, a gel to repair cracks in bending electronics, self-repairing electrical insulators and a stretchy ionic conductor.
The team's paper, An Autonomously Self-Healing, Liquid Metal-Elastomer Composite for Robust Soft-Matter Electronics, has been published in the journal Nature Materials.
There's a video demonstrating the breakthrough below.
Source: Carnegie Mellon University