Microcube is designed so that pressure makes it expand instead of compress
J. Qu, Muamer Kadic and Martin Wegener
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.
This counterintuitive material is made up of a grid of hollow 3-D crosses — shaped like six-way pipe fittings — mere micrometers across. When surrounding pressure of air, water or some other substance increases, the crosses’ circular surfaces bow inward. Because of the way these crosses are connected with levers, that warping forces the crosses to rotate and push away from each other, causing the whole structure to expand, says study coauthor Jingyuan Qu, a physicist at Karlsruhe Institute of Technology in Germany.
The researchers were “very clever about how they connected this quite complex set of structural elements,”