Liquid Metals to Enable the Use of Self-Healing Electronics

A collaborative, multi-disciplinary team of the US Air Force Research Laboratory (AFRL) are researching concepts to make self-healing electronics, antennas changing shape and function with the flick of a switch and clothing woven with conductive threads connecting devices, a reality. The AFRL team recently demonstrated that non-toxic liquid metals are capable of creating multi-functional, reconfigurable electronics and flexible power connections for non-traditional electronics, with potential applications in a number of Air Force mission and other domains.

A researcher at AFRL with liquid metal.The research team demonstrated that non-toxic, conductive Gallium Liquid Metal Alloys could be flowed through channels embedded into an airframe to behave as radio frequency antennas. Unlike traditional, solid antennas that are only operable within a specific frequency range based on their size and location, the liquid metal antennas can then be reconfigured within the airframe to operate at new frequency ranges and provide additional operational directivity. The liquid metal also enables increased functionality without adding additional material to the platform, as in contrast to the multiple radio frequency systems that may impact the size, weight and power available to an aircraft.

Although the liquid metal antennas have proved to be mission capable in the laboratory setting, the AFRL team is still in the process of maturing the technology for transition to the war-fighter where the challenges include precise control of the interfaces between the liquid metals and other traditional electronic systems as well as the residue left when the liquid metal is removed from one channel and flowed into another causing interference. They are also working with industry partners to develop packaging for the material to make sure it works in application platforms that may have traditional electronic systems on board.

In the future, the research team wants to use liquid metals in the aerospace electronics domain too. They currently have an effort underway along with the flexible electronic materials research team, exploring the potential for liquid metals to power flexible electronic devices such as human performance monitoring sensors and wearable devices. The AFRL researchers are also looking at a new project to use liquid metals for self-healing electronics by transforming them into microscopic nano-particles which can repair failure points on traditional electronic circuits without replacement.