Science Daily  July 20, 2020 An international team of researchers (UK, Germany) has created a bio-inspired metallic cellular structure (with an internal grid of large ceramic segments). It is non-cuttable by an angle grinder and a power drill, and it has only 15% steel density. The architecture derives its extreme hardness from the local resonance between the embedded ceramics in a flexible cellular matrix and the attacking tool, which produces high-frequency vibrations at the interface. The contrast between the ceramic segments and cellular material was also effective against a waterjet cutter because the convex geometry of the ceramic spheres. Shifting […]