Reibold and her colleagues assume that the blacksmiths eventually created nanostructures by tediously trying different methods that made up the secret of their special strength. The cyclic heating and shaping of the steel promotes the formation of carbon nanotubes, which in turn contribute to the formation of the microscopically thin filaments of iron carbide, the researchers suspect.
For the production of Damascus steel, so-called Wootz was imported from India. This steel contained a high proportion of carbon, which caused a great deal of damage to European forging, because at high temperatures it forms iron carbide. This compound is very hard and wear-resistant, but makes the forged brittle and poorly moldable. For a long time, the Europeans remained mystified how the weaponsmiths of the Orient could produce their high-quality swords.Marianne Reibold (Dresden University of Technology) et al .: Nature, Vol. 444, p. 286 ddp / science.de? Sabine Keuter advertisement