Eric Klien
A liquid metal lattice that can be crushed but returns to its original shape on heating has been developed by Pu Zhang and colleagues at Binghamton University in the US. The material is held together by a silicone shell and could find myriad uses including soft robotics, foldable antennas and aerospace engineering. Indeed, the research could even lead to the creation of a liquid metal robot evoking the T-1000 character in the film Terminator 2.
The team created the liquid metal lattice using a special mixture of bismuth, indium and tin known as Field’s alloy. This alloy has the relatively unusual property of melting at just 62 °C, which means it can be liquefied with just hot water. Field’s alloy already has several applications – including as a liquid-metal coolant for advanced nuclear reactors.
Zhang and colleagues combined the alloy with a silicone shell through a complex hybrid manufacturing process that combines 3D printing, vacuum casting and so-called “conformal coating” – a technique normally used to coat circuit boards in a thin polymer layer to protect them against the environment. The silicone shell is what allows the lattice to “remember” a desired shape and restore such when the alloy is melted.