Very often we face the problem when a small piece of electronics, such as a microchip or a wire, may cause damage of the complete electronic device. We often need to replace the whole part or the device with the new one. Researchers at the University of Illinois have developed revolutionary self-healing circuit that will allow for self-reparation of the cracked electronic devices. The way researchers achieved this was placing 10-micron microcapsules along the length of the circuit. The tiny microcapsules were filled with a self-healing liquid metal made of gallium-indium alloy inside. When the circuit got damaged leading to the loss of conductivity, the capsules cracked.
The self-healing liquid flowed out from the capsule into the damaged piece of the circuit and restored the connectivity. The self-healing liquid metal was so effective that it restored up to 99% of lost conductivity and damaged operation. To prove the theory, researchers have places the lines of gold onto glass to form a circuit. Microcapsules of 0.01mm width were placed directly onto the lines. Alternatively, a thin laminate can also be used into which larger 0.2mm microcapsules are embedded. In both cases the microcapsules were filled by the eutectic gallium-indium. This device was then placed between another layer of glass and acrylic and connected to electricity. Then experimenters have bent the circuit until it got damaged. The voltage in the circuit felt down to zero. Within one millisecond, the self-healing liquid metal has repaired the circuit and restored most part of the initially measured voltage. The smaller capsules healed the device every time but were a little less conductive than the larger ones which had a slightly lower success rate. The team suggested that a combination of differently sized capsules would therefore give the best result. According to BBC record, the self-healed circuit did not lose its conductivity within the period of observations which make researchers to confirm that the healing metal material is reliable and long-lasting solution in case of damages. The self-healing process takes so little time to recover that in some cases the damage will not be even noticed. Researchers hope that the new technology may be used not only in creating sustainable gadgets but also in interplanetary travel.