Integrated circuits may have enabled the digital age, but they are still subject to one great limitation: physical damage. A new coating developed at the University of Illinois will be able to bring a dead circuit back to life in less than a millisecond, even if you “take an X-Acto knife and slice through it,” says engineer Nancy Sottos. Her team coated gold wires with microscopic capsules of liquid metal. When a wire snaps, the capsules break open and the liquid metal fills the crack, restoring electrical conductivity. Within 5 to 10 years, similar self-healing coatings could cover the wires that connect the components of circuit boards, Sottos says, giving nearly any computer or gadget the ability to repair itself. —L.A.
By donning different clothing, people can prepare for the sun, rain, and cold—but never before have shirts or pants intelligently adapted to their environment. Anna Balazs, an engineer at the University of Pittsburgh, says that within two decades “your clothes could do the thinking for you.” A material developed at Pitt and Harvard can regulate Its tem-
perature to keep within a certain range. A chemical and mechanical feedback loop within its layers turns a heat-producing reaction on and off at preprogrammed degrees. The same strategy could be used to make materials that self-regulate In response to other stimuli, such as pH, light, or glucose—meaning water pipes, windows, and medical devices could be just as smart. — S.F.
“In many areas of materials science, we’ve reached the best we can do with engineering techniques,” says McGill University engineer Francois Barthelat. “I think nature has a lot of new tricks to teach us.” The protective armor of many marine animals Is up to 3,000 times tougher than the materials that form it. By replicating the structure offish scales, Barthelat similarly amplified the toughness of a composite material. Engineers at Villanova University stacked ceramic crystals in a softer compound at angles similar to those In a conch shell. Because cracks zigzag and peter out instead of shattering the material, it Is 10 times as strong as the base ceramic. Such advances could fortify armor in three to five years. —L.A. F$