The First Manufactured "Non-Cuttable" Material

Inspired by grapefruit's tough cellular skin and the fracture-resistant shells of the abalone sea creature, engineers at Durham University  have created a "non-cuttable" material called "Proteus." The material is made from alumina ceramic spheres encased in a cellular aluminum metallic foam structure, and it works by turning the force of a cutting tool back on itself. In tests, the material could not be cut by angle grinders, drills, or high-pressure water jets. Proteus could be used for armor and protective equipment.