For centuries, blades made of Damascus steel were know to be among the sharpest and strongest in the world. The steel itself, called wootz, bears distinctive patterns created during the forging of the metal, and the understanding was that impurities in the iron ore used to make the steel were the cause of these patterns. The technique for making Damascus steel was discontinued in the 18th century, but many examples of the metal and the craftsmanship involved in turning it into blades remain.
The journal “Nature” reports that researchers at Dreseden University in Germany have subjected some sample blades to electron microscopy and have discovered that the steel actually contains a type of carbon nanotubes and also nanowires that come from the use of the mineral cementite. The nanostructures are responsible for the added strength of the material, according to the researchers, however there are critics who discount the findings.
