The sword of Damascus

A long time ago swords were ones of the main weapons of humans for centuries. For that reason there was always space for a good sword. Is the sword of Damascus the best sword ever made and what kind of sword it actually is? This is the short report about the sword of Damascus and how it was created.

Picture 1. The sword of Damascus. [Tipusword2]
The sword of Damascus was made in Damascus, a city in Syria. It is not known when the first sword of Damascus was produced. The sword became well known at the first time when the Western Europeans saw these swords in the hands of Muslim warriors throughout the Crusades. [1] Crusades happened between 1095-1270AD. [2] There are still mentions about swords already in 330 BC which was the era of the Alexander the Great. [3] Until this day the manufacturing technique of the sword was unknown. Last Islamic blacksmiths who were able to make these swords were died in the mid-18th century and the European blacksmiths were never able to duplicate the sword of Damascus. [2]

Even though swords were made in Damascus, the raw material still did not come from Damascus. The raw material for swords was imported from India and it was called Wootz. Wootz was produced from low-carbon bloom-iron. Bloom-iron was translated into wootz by first carbonizing it in a sealed pot with charcoal. Annealing time was 14 hours and the temperature was about 1000-1100 0C. The iron cooling rate was slow because then the grain boundaries of austenite consisted a homogeneous phase of cementite. Usually cementite phase is very fragile but not in that case because of many different heat-treats before the hardening. This cementite phase caused the characteristic Damascus wavy pattern. Old history books give us some details how the sword of Damascus was heat-treated “Bulat is heated up till it does not shine anymore but has the color of rising sun of the desert. After that it is cooled down and when it´s color is like kings purple it has to be stuck in muscular slave”. Bulat is another name for Damascus steels. [3]

Picture 2. Damascus pattern. [tf.uni-kiel.de]

The sword of Damascus has many mechanical properties which are difficult to achieve even nowadays. Damascus steel has also superplastic properties, which means that steel does not break when it is under a heavy load. Steels have also very high tensile strength, which is at least 4000 MPa and at the same time fracture toughness is about 30 %. For comparison should be mentioned that steel of Damascus was almost two times stronger than the best modern steel alloys. The most important reason why we do not use this steels is that steel cannot be manufactured massively. Only amorphous steels can match Damascus steels but there are still major problems in creating them. [3]

So in the end it is remarkable how the old blacksmiths were able to manufacture the swords without any knowledge of the modern metallurgy and without understanding the complex crystalline structure of metals. At the moment these swords are the best ever made swords in the whole human history.

-Marko

References

[1] The following paper, The Mystery of the Damascus Sword by John Verhoeven and Alfred Pendray appeared in Muse, Volume 2, Number 2, pp. 35-43, April 1998.

[2] Damascus Steel - Sword Makers of the Islamic Civilization, Ancient Technolocy and Modern Alchemy, By K. Kris Hirst, About.com Guide

[3] METALLIEN HISTORIA, Pentti O. Kettunen, Materiaaliopin laitos, Tampereen teknillinen yliopisto