Team of scientists creates rubber ‘exoskeleton’ to keep liquid metal structures in shape

Imagine a metal device that can be compressed into a compact ball and automatically “bloom” when heated,media New Atlas reported. And now a newly developed liquid metal lattice is expected to make it possible soon. Led by Pu Zhang, an associate professor at the State University of New York at Binghamton, a team of scientists began studying the mesh structure by printing out an existing metal called the Field alloy in 3D.

Team of scientists creates rubber 'exoskeleton' to keep liquid metal structures in shape

Named after its inventor, chemist Simon Quellen Field, the alloy consists of a mixture of vanadium, palladium and tin. It melts when heated to 62 degrees C (144 degrees F), but refreezes when cooled. Using a combination of vacuum casting and protective coating techniques, these alloy lattices are then covered with a layer of rubber. As long as the ambient temperature remains below 62 degrees, the resulting structure remains rigid.

However, once heated above that temperature, the alloy melts, but is still contained in the rubber housing. In this form of plasticity, the structure can be flattened or deformed. If the alloy cools and re-hardens while maintaining this shape, they will maintain this changed shape indefinitely.

Team of scientists creates rubber 'exoskeleton' to keep liquid metal structures in shape

However, when reheated to more than 62 degrees, the alloy melts again. Just as rubber toys bounce back into their original shape when they are squashed, the rubber shells of the lattice plates can also be restored to their original shape, pulling the liquid metal back into place. When they cool down, the alloy hardens again into a “fit” shape.

So far, the team has used the technology to create spider-web-like antennas, footballs, hives, and even hands like Terminator 2, which open as the alloy melts. It is conceivable that the lattice could also be used in applications such as the spacecraft’s landing gear, which can absorb collision energy by bending, but then return to its original shape after heating and cooling.

“Normally, engineers use aluminum or steel to make a buffer structure, but when you land on the moon, the metal absorbs energy and deforms. That’s over — you can only use it once,” Pu Zhang said. “With this Field alloy, you can hit it like any other metal, but then heat it up and you can restore its shape. You can use it again and again. “

The study was described in a recent paper published in the journal Additive Manufacturing.