Abstract

This is a story about a most elegant structure created in steel, consisting of crystals that are packed together so tightly that the boundaries between them occupy a hundred million square metres in just a metre cube of the material. This can be done in many ways, but only one method has succeeded thus far in a concept that can be scaled to the production of thousands of tonnes or more of useful metal. And using a manufacturing technology that does not involve violent processing or thermal treatments; instead, the structure evolves gently over a period of days at temperatures where food is normally cooked.

The method relies on a special choreography of atoms, where a crystal structure change is achieved without breaking any bonds. The resulting disciplined motion of atoms leads to exceptionally fine product crystals that make the steel very strong, and yet able to absorb energy on impact. The applications and limitations of this new material are described, together with possible ways towards the design of a different concept that has the potential of creating an apparently impossible combination of properties.