Self-healing material mimics the resilience of soft biological tissue

Imagine first-responder robots that instantly heal themselves when damaged, or wires that continue to conduct electricity when cut
May 21, 2018

A self-healing material that spontaneously repairs itself in real time from extreme mechanical damage, such as holes cut in it multiple times. New pathways are formed instantly and autonomously to keep this circuit functioning and the device moving. (credit: Carnegie Mellon University College of Engineering)

Carnegie Mellon University (CMU) researchers have created a self-healing material that spontaneously repairs itself under extreme mechanical damage, similar to many natural organisms. Applications include bio-inspired first-responder robots that instantly heal themselves when damaged and wearable computing devices that recover from being dropped.

The new material is composed of liquid metal droplets suspended in a soft elastomer (a material with elastic properties, such as rubber). When damaged, the droplets rupture to form new connections with neighboring droplets, instantly rerouting electrical signals. Circuits produced with conductive traces of this material remain fully and continuously operational when severed, punctured, or have material removed.

“Other research in soft electronics has resulted in materials that are elastic, but are still vulnerable to mechanical damage that causes immediate electrical failure,” said Carmel Majidi, PhD, a CMU associate professor of mechanical engineering, who also directs the Integrated Soft Materials Laboratory. “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.”

The self-healing material also exhibits high ability to conduct electricity, which is not affected when stretched. That makes it ideal for uses in power and data transmission, as a health-monitoring device on an athlete during rigorous training, or an inflatable structure that can withstand environmental extremes on Mars, for example.

Reference: Nature Materials. Source: Carnegie Mellon University.