Materials scientists from the University of Virginia, University of California Santa Barbara, and the University of Aberdeen, Scotland, have created a lightweight, solid foam known as Isomax™.The material has the highest possible stiffness for the lowest possible weight. Credit: University of Aberdeen

Metamaterials are engineered to have properties not found in nature, and put together using multiple elements fashioned from materials such as metals or plastics. The researchers have made it possible to produce a lightweight material with high stiffness by making a cellular system. The design provides a material that has the highest possible stiffness for the lowest possible weight.

Isomax™ could be used in the construction of prosthetics and load-bearing components in aviation, aerospace, and shipping. The mesoscale geometry of the low-density mechanical metamaterial can facilitate large crushing strains with high energy absorption, optical bandgaps, and mechanically tunable acoustic bandgaps, high thermal insulation, buoyancy, and fluid storage and transport.

The researchers say that one of the most satisfying things about this breakthrough is that the theorem telling them the stiffness of the optimal design was proved in the 1960s, but up until now, no one has produced a design that achieved this.