In Sir Walter Scott's book The Talisman, he recreated the scene of October 1192, when Richard Lionheart of England and Saladin the Saracen met to end the Third Crusade (there would be five more after Richard retired to England, depending on how you count your crusades).
Scott imagined an arms demonstration between the two men, Richard wielding a good English broadsword and Saladin, a scimitar of Damascus steel, "a curved and narrow blade, which glittered not like the swords of the Franks, but was, on the contrary, of a dull blue colour, marked with ten millions of meandering lines..." This fearsome weapon, at least in Scott's overblown prose, represented the winner in this medieval arms race... or at least a fair match.
Damascus Steel: Understanding the Alchemy
The legendary sword known as the Damascus steel intimidated the European invaders into the 'Holy Lands' of the Islamic civilization throughout the Crusades (AD 1095-1270). Blacksmiths in Europe attempted to match the steel, using the pattern welding technique of alternating layers of steel and iron, folding and twisting the metal during the forging process.
(Pattern welding was a technique used by swordmakers from around the world, including Celts of the 6th century BC, Vikings of the 11th century AD and the 13th century Japanese.)
In some cases, the European blacksmiths etched the blade or overlaid the surface of the blade with silver or copper filigree to imitate the characteristic watery lines of the Damascus steel blade. Some scholars credit this search for the Damascus steel process as the origins of modern materials science. But the European blacksmiths never duplicated the solid core Damascus steel, and the secret of its construction was lost even to the Islamic blacksmiths in the mid-18th century.
Wootz Steel and Saracen Blades
What is known today about "true" or "oriental" Damascus steel is that it was made from a raw material called wootz steel. Wootz was an exceptional grade of iron ore steel first made in southern and south central India and Sri Lanka perhaps as early as 300 BC. Wootz was extracted from raw iron ore and formed using a crucible to melt, burn away impurities and add important ingredients, including a high carbon content (nearly 1.5% by weight---wrought iron typically has carbon content around .1%).
The high carbon content is the key--and the achilles heel--in the manufacturing process. High carbon content makes the keen edge and its durability possible; but its presence in the mixture is almost impossible to control.
Too little carbon and the resulting stuff is wrought iron, too soft for these purposes; too much and you get cast iron, too brittle. If the process doesn't go right, the steel forms plates of cementite, a phase of iron which is hopelessly fragile. Somehow, Islamic metallurgists were able to control for the inherent fragility and forge the raw material into fighting weapons, an ability that somehow was lost in the mid-18th century.
But the problem is: it doesn't really make any sense that blacksmiths would lose such a useful technology. Since the knowledge of the forgers has been lost many researchers have sought it, and in fact this report is based on their findings over the past decade or more. But in a recent article in Nature, a research team led by Peter Paufler at the University of Dresden report that they may have an idea of the mechanics of how the high carbon steel was created and why it disappeared. That idea lies in that most modern of materials sciences: nanotechnology.
The word 'nanotechnology' might seem a little odd to be applied to a technology that is clearly several centuries old. After all, a 'nanometer' is something that means one billionth part of meter, something no one could have measured until very recently. But in this sense, nanotechnology refers to the purposeful (and accidental) inclusion of very very tiny amounts of materials to create chemical reactions at the quantum level.
Nanotechnology played a role in the mixing of Maya blue, that amazing color in Maya murals from 8th century America. Stained glass windows from the European Renaissance, colored glasses in Bronze Age Egypt, and violins from the 18th century master Stradivari all benefited from the creative use of tiny amounts of inclusions of foreign matter placed into created objects, creating quantum level qualitative changes in the product. Nanotechnology then is alchemy in its most pure form.
And so, nanotechnology--the inclusion of tiny amounts of foreign matter into a smelted iron product--had a crucial role in the construction of the Damascan blade. But... what were those elements and how did they get in there? The secret alchemy of making a Damascan blade was lost by the middle of the 18th century.
European blacksmiths before then, and all those who came before the end of the last century who attempted to make their own blades failed to overcome the problems inherent in a high-carbon content, and could not explain how ancient Syrian blacksmiths achieved the filigreed surface and quality of the finished product.
Damascan Steel and Electron Microscopy
What the research team led by Paufler has done has been to use current nanotechnology to examine the microstructure of a Damascan blade using a scanning electron microscope. Investigations have determined that there are two pieces involved to this puzzle: both inclusions into the raw ore itself and the forging process completed in the mideast.
Known purposeful additions to Wootz steel include the bark of Cassia auriculata (used in tanning) and the leaves of Calotropis gigantea (a milkweed). Spectroscopy has also identified tiny amounts of vanadium, chromium, manganese, cobalt, and nickel, and some rare elements, traces of which presumably came from the mines in India.
These materials were already in the raw steel, but what Paufler and associates also identified in the steel were quantum level changes made in the metal which must have occurred during manufacture.
They postulate that during the smith's cyclic heating and forging processes, the metal developed a microstructure called 'carbide nanotubes', extremely hard tubes of carbon that are expressed on the surface and create the blade's hardness. Thus, by blending the unique characteristics of Wootz steel with a forging process that included tiny amounts of specialized materials, the blacksmiths of the Islamic Civilization were able to create the Damascan steel.
What happened in the mid-18th century was that the chemical makeup of the raw material altered--the minute quantities of one or more of the minerals disappeared, perhaps because the particular lode was exhausted. Such a difference would not have been apparent to the blacksmith visually; but, interestingly, the blacksmiths may have extended the life of the process by including small pieces of the previous batch in each new batch.
We modern archaeologists like to say that the elite stuff, the expensive goods that were restricted to the upper classes, really have no interest to us. But cracking the code of how metallurgists made the elite Damascus steel! I vote for that.
Helmut Föll. n.d. Damascene Technique in Metalworking. This is a fascinating website in English and German by materials scientist Föll of the University of Kiel, with lots of details about the process and history of Damascus steel.
Lee A. Jones. 1998. Blade Patterns Intrinsic to Steel Edged Weapons. On Helmut Föll's website.
M. Reibold et al. 2006. Carbon nanotubes in an ancient Damascus sabre. Nature 444:286.
Sharada Srinivasan and Srinivasa Ranganathan. 2004. India's Legendary Wootz Steel: An advanced material of the ancient world. National Institute of Advanced Studies and the Indian Institute of Science in Bangalore.
S. Srinivasan and S. Ranganathan. ca. 1997. Wootz Steel: An Advanced Material of the Ancient World.
John D. Verhoeven. 2001. The Mystery of Damascus Blades. Scientific American
J.D. Verhoeven, A.H. Pendray, and W.E. Dauksch. 1998. The Key Role of Impurities in Ancient Damascus Steel Blades. JOM 50(9):58-64.
Sword of Saladin - Kingdom of Heaven
“October 1192, Richard ‘The Lion Heart’, king of England who lead Christian crusading knights in an attempt to reclaim Jerusalem from the Muslims meet his great enemy Salahuddin Al Ayyubi (In western known as ‘Saladin’). They respect each other and become a legend”. Sir Walter Scott dramatized in his novel “The Talisman”.
They showed off their weapons, Richard used his large shiny blade made by greatest armourer in Great Britain while Salahuddin Al Ayyubi showed his favorite blade, a curved blade made by armourer in Damascus.
“He unsheathed his scimitar, a curved and narrow blade, which glittered not like the swords of the Franks, but was, on the contrary, of a dull blue colour, marked with ten millions of meandering lines, which showed how anxiously the metal had been welded by the armourer”.
Sir William Scott’s novel that has been published 2 centuries ego ensures us about the greatness of Damascus’s blade. The blade is so sharp so that the smoothest silk can be cut 2 pieces if it’s fallen on top of the blade, it can cut a mountain rock without losing its’ sharpness.
These ‘Damascus blades’ were extraordinarily strong, but still flexible enough to bend from hilt to tip. And they were reputedly so sharp that they could cleave a silk scarf floating to the ground, just as readily as a knight’s body.
These superlative weapons gave the Muslims a great advantage, and their blacksmiths carefully guarded the secret to their manufacture. The secret died eventually died out in the eighteenth century and no European smith was able to reproduce their method.
Now, Marianne Riebold and colleagues from the University of Dresden have uncovered the startling origins of Damascus steel using a technique unavailable to the sword-makers of old – electron microscopy.
Damascus blades were forged from small cakes of steel from India called ‘wootz’. All steel is made by allowing iron with carbon to harden the resulting metal. The problem with steel manufacture is that high carbon contents of 1-2% certainly make the material harder, but also render it brittle.
This is useless for sword steel since the blade would shatter upon impact with a shield or another sword. Wootz, with its especially high carbon content of about 1.5%, should have been useless for sword-making. Nonetheless, the resulting sabres showed a seemingly impossible combination of hardness and malleability.
Riebold’s team solved this paradox by analysing a Damascus sabre created by the famous blacksmith Assad Ullah in the seventeenth century, and graciously donated by the Berne Historical Museum in Switzerland.
They dissolved part of the weapon in hydrochloric acid and studied it under an electron microscope. Amazingly, they found that the steel contained carbon nanotubes (see left), each one just slightly larger than half a nanometre. Ten million could fit side by side on the head of a thumbtack.
Carbon nanotubes are cylinders made of hexagonally-arranged carbon atoms. They are among the strongest materials known and have great elasticity and tensile strength. In Riebold’s analysis, the nanotubes were protecting nanowires of cementite (Fe3C), a hard and brittle compound formed by the iron and carbon of the steel.
Here is the answer to the steel’s special properties – it is a composite material at a nanometre level. The malleability of the carbon nanotubes makes up for the brittle nature of the cementite formed by the high-carbon wootz cakes.
It isn’t clear how ancient blacksmiths produced these nanotubes, but the researchers believe that the key to this process lay with small traces of metals in the wootz including vanadium, chromium, manganese, cobalt and nickel. Alternating hot and cold phases during manufacture caused these impurities to segregate out into planes.
From there, they would have acted as catalysts for the formation of the carbon nanotubes, which in turn would have promoted the formation of the cementite nanowires. These structures formed along the planes set out by the impurities, explaining the characteristic wavy bands, or damask (see image at top), that patterns Damascus blades.
By gradually refining their blade-making skills, these blacksmiths of centuries past were using nanotechnology at least 400 years before it became the scientific buzzword of the twenty-first century.
The ore used to produce wootz came from Indian mines that were depleted in the eighteenth century. As the particular combination of metal impurities became unavailable, the ability to manufacture Damascus swords was lost.
Now, thanks to modern science, we may eventually be able how to replicate these superb weapons and more importantly, the unique steel they were shaped from.
Salah satu pusat pembuatan pedang dengan teknologi yang termasyhur pada zaman kekhalifahan adalah Damsyik, Syria. Seni pembuatan pedang dengan teknologi tinggi dalam peradaban Islam bermula pada abad ke-9 M. Sejarawan Al-Qalqashandi dalam buku berjudul, Subh Al Asha, mencatatkan bahawa pada abad ke-12 M Damsyik menjadi pusat penghasilan besi yang sangat masyhur.