Damascus steel and carbon nanotubes

[Astronuc]

The secrets of Damascus steel production were lost in the 18th century. But Peter Paufler and colleagues at the Technical University in Dresden used high-resolution electron microscopy to analyze a specimen from a Damascus saber produced during the 17th century.

Paufler's team discovered the microstructure of Damascus steel consists of elements introduced during the forging process that gave rise to what must be the earliest carbon nanotubes on record. And those, in turn, might have contributed to the formation of iron carbide nanowires, which might explain the characteristic strength and beautiful banding pattern of Damascus blades.

from UPI

Materials: Carbon nanotubes in an ancient Damascus sabre
Nature 444, 286 (16 November 2006) | doi:10.1038/444286a; Received 24 July 2006; Accepted 25 October 2006; Published online 15 November 2006
http://www.nature.com/nature/journal/v444/n7117/abs/444286a.html

M. Reibold^1,2, P. Paufler¹, A. A. Levin¹, W. Kochmann¹, N. Pätzke¹ and D. C. Meyer¹
1. Institut fur Strukturphysik, Technische Universität Dresden, 01062 Dresden, Germany
2. Triebenberg Laboratory, Technische Universität Dresden, 01062 Dresden, Germany

The steel of Damascus blades, which were first encountered by the Crusaders when fighting against Muslims, had features not found in European steels — a characteristic wavy banding pattern known as damask, extraordinary mechanical properties, and an exceptionally sharp cutting edge. Here we use high-resolution transmission electron microscopy to examine a sample of Damascus sabre steel from the seventeenth century and find that it contains carbon nanotubes as well as cementite nanowires. This microstructure may offer insight into the beautiful banding pattern of the ultrahigh-carbon steel created from an ancient recipe that was lost long ago.