A newly fabricated material does more than just hold up under pressure.
Unlike many ordinary objects that shrink when squeezed, the metamaterial – a synthetic structure designed to exhibit properties not typically found in natural materials – expands at higher pressures.
When surrounding pressure of air, water or some other substance increases, the crosses’ circular surfaces bow inward. When the researchers placed the material inside a gas chamber and cranked up the air pressure from one bar to five bars, the cube’s volume increased by about 3 percent. Adjusting the thickness of the crosses’ surfaces could make this new metamaterial more or less expandable: The thicker it is, the less the structure expands.
A metamaterial fine-tuned to stay the same size under a wide range of pressures could be used to build equipment that withstands the crushing pressures of the deep sea or the vacuum of outer space.
PRESSURE’S ON Under increasing pressure, the hollow 3-D crosses of this metamaterial deform and twist away from each other, making the whole lattice expand, as seen in this simulation.