Think carbon nanotubes are new-fangled? Think again. The Crusaders felt the might of the tube when they fought against the Muslims and their distinctive, patterned Damascus blades.
Sabres from Damascus, now in Syria, date back as far as 900 AD. Strong and sharp, they are made from a type of steel called wootz.
Their blades bear a banded pattern thought to have been created as the sword was annealed and forged. But the secret of the swords' manufacture was lost in the eighteenth century.
Materials researcher Peter Paufler and his colleagues at Dresden University, Germany, have taken electron-microscope pictures of the swords and found that wootz has a microstructure of nano-metre-sized tubes, just like carbon nanotubes used in modern technologies for their lightweight strength.
The tubes were only revealed after a piece of sword was dissolved in hydrochloric acid to remove another microstructure in the swords: nanowires of the mineral cementite.
More.
No comments:
Post a Comment