Damascus Steel : The Best Sword In The World
Damascus steel was a term used by several Western cultures from the Medieval period onward to describe a type of steel used in swordmaking from about 300 BC to AD 1700. These swords are characterized by distinctive patterns of banding and mottling reminiscent of flowing water. Such blades were reputed to be not only tough and resistant to shattering, but capable of being honed to a sharp and resilient edge. Today, the term is used to describe steel that mimics the appearance and performance of Damascus steel, usually that which is produced by either crucible forging or pattern welding.
The original method of producing Damascus steel is not known. Due to differences in raw materials and manufacturing techniques, modern attempts to duplicate the metal have not been entirely successful. Despite this, several individuals in modern times have claimed that they have rediscovered the methods in which the original Damascus steel was produced.
The reputation and history of Damascus steel have given rise to many legends, such as the ability to cut through a rifle barrel or to cut a hair falling across the blade, but no evidence exists to support such claims. A research team in Germany published a report in 2006 revealing nanowires and carbon nanotubes in a blade forged from Damascus steel. This finding was covered by National Geographic and the New York Times. Although modern steel outperforms these swords, microscopic chemical reactions in the production process may have made the blades extraordinary for their time. Some experts expect to discover such nanotubes in more relics as they are analyzed more closely.
The original method of producing Damascus steel is not known. Due to differences in raw materials and manufacturing techniques, modern attempts to duplicate the metal have not been entirely successful. Despite this, several individuals in modern times have claimed that they have rediscovered the methods in which the original Damascus steel was produced.
The reputation and history of Damascus steel have given rise to many legends, such as the ability to cut through a rifle barrel or to cut a hair falling across the blade, but no evidence exists to support such claims. A research team in Germany published a report in 2006 revealing nanowires and carbon nanotubes in a blade forged from Damascus steel. This finding was covered by National Geographic and the New York Times. Although modern steel outperforms these swords, microscopic chemical reactions in the production process may have made the blades extraordinary for their time. Some experts expect to discover such nanotubes in more relics as they are analyzed more closely.
Several theories on the origins of the term "Damascus steel" exist, but none of them may be confirmed definitively. Damascus may refer to:
> The swords forged in Damascus. For instance, al-Kindi, refers to swords made in Damascus as Damascene. This word has often been employed as an epithet in Eastern European legends (Sabya Damaskinya or Sablja Dimiskija meaning "Damascene saber"), including the Serbian and Bulgarian legends of Prince Marko, a historical figure of the late 14th century in what is currently the Republic of Macedonia.
> The swords sold in Damascus.
> The name of the swordsmith. For instance, the author al-Beruni refers to swords made by a man he names Damashqi.
> The comparison of the patterns found on the swords to Damask fabrics woven in the Byzantine empire.
Historians such as Hobson, Sinopoli, and Juleff state that the original damascus was produced from ingots of wootz steel, which originated in India and Sri Lanka and later spread to Persia.From the 3rd century to the 17th century, India was shipping steel ingots to the Middle East for use in Damascus steel.
European researchers have demonstrated that high quality swords with damask patterns were produced by various pattern welding techniques since at least the 3rd century BC by the Celts and Germanic peoples.
Loss of the technique
Production of these patterned swords gradually declined, ceasing by around 1750, and the process was lost to metalsmiths. Several modern theories have ventured to explain this decline, including the breakdown of trade routes to supply the needed metals, the lack of trace impurities in the metals, the possible loss of knowledge on the crafting techniques through secrecy and lack of transmission, or a combination of all the above.
The raw material for producing the original Damascus steel is believed to be wootz imported from India. Due to the distance of trade for this raw material, a sufficiently lengthy disruption of the trade routes could have ended the production of Damascus steel and eventually led to the loss of the technique. As well, the need for key trace impurities of tungsten or vanadium within the materials needed for production of the steel may be absent if this material was acquired from different production regions or smelted from ores lacking these key trace elements. The technique for controlled thermal cycling after the initial forging at a specific temperature could also have been lost, thereby preventing the final damask pattern in the steel from occurring.
The discovery of carbon nanotubes in the Damascus steel's composition supports this hypothesis, since the precipitation of carbon nanotubes likely resulted from a specific process that may be difficult to replicate should the production technique or raw materials used be significantly altered.
Recreating Damascus steel is a subfield of experimental archaeology. Many have attempted to discover or reverse-engineer the process by which it was made.
Moran: billet welding
Since the well-known technique of pattern welding produced surface patterns similar to those found on Damascus blades, some believe that Damascus blades were made using this technique. Pattern-welded steel has been referred to as "Damascus steel" since 1973 when Bladesmith William F. Moran unveiled his "Damascus knives" at the Knifemakers' GuildShow. This "Modern Damascus" is made from several types of steel and iron slices welded together to form a billet. The patterns vary depending on how the smith works the billet. The billet is drawn out and folded until the desired number of layers are formed. In order to attain a Master Smith rating with the American Bladesmith Society that Moran founded, the smith must forge a damascus blade with a minimum of 300 layers.
Verhoeven and Pendray: crucible
J. D. Verhoeven and A. H. Pendray published an article on their attempts to reproduce the elemental, structural, and visual characteristics of Damascus steel. They started with a cake of steel that matched the properties of the original wootzsteel from India, which also matched a number of original Damascus swords to which Verhoeven and Pendray had access. The wootz was in a soft, annealed state, with a grain structure and beads of pure iron carbide which were the result of itshypereutectoid state. Verhoeven and Pendray had already determined that the grains on the surface of the steel were grains of iron carbide—their goal was to reproduce the iron carbide patterns they saw in the Damascus blades from the grains in the wootz.
Although such material could be worked at low temperatures to produce the striated Damascene pattern of intermixed ferrite and cementite bands in a manner identical to pattern-welded Damascus steel, any heat treatment sufficient to dissolve the carbides would permanently destroy the pattern. However, Verhoeven and Pendray discovered that in samples of true Damascus steel, the Damascene pattern could be recovered by aging at a moderate temperature. They found that certain carbide forming elements, one of which was vanadium, did not disperse until the steel reached higher temperatures than those needed to dissolve the carbides. Therefore, a high heat treatment could remove the visual evidence of patterning associated with carbides but did not remove the underlying patterning of the carbide forming elements; a subsequent lower-temperature heat treatment, at a temperature at which the carbides were again stable, could recover the structure by the binding of carbon by those elements.
Anosov, Wadsworth and Sherby: bulat
In Russia, chronicles record the use of a material known as bulat steel to make highly valued weapons, including swords, knives and axes. Tsar Michael of Russia reportedly had a bulat helmet made for him in 1621. The exact origin or the manufacturing process of bulat is unknown, but it was likely imported to Russia via Persia, and it was similar and possibly the same as damascus steel. Pavel Petrovich Anosov made several attempts to recreate the process in the mid-19th century. Wadsworth and Sherby also researched the reproduction of Bulat steel and published their results in 1980.
In Russia, chronicles record the use of a material known as bulat steel to make highly valued weapons, including swords, knives and axes. Tsar Michael of Russia reportedly had a bulat helmet made for him in 1621. The exact origin or the manufacturing process of bulat is unknown, but it was likely imported to Russia via Persia, and it was similar and possibly the same as damascus steel. Pavel Petrovich Anosov made several attempts to recreate the process in the mid-19th century. Wadsworth and Sherby also researched the reproduction of Bulat steel and published their results in 1980.
Additional research
A team of researchers based at the Technical University of Dresden that used x-rays and electron microscopy to examine Damascus steel discovered the presence of cementite nanowires andcarbon nanotubes. Peter Paufler, a member of the Dresden team, says that these nanostructures are a result of the forging process.
Sanderson proposes that the process of forging and annealing accounts for the nano-scale structures.
Prior to the early 20th century, all shotgun barrels were forged by heating narrow strips of iron and steel and shaping them around a mandrel. This process was referred to as "laminating" or "Damascus" and these barrels were found on shotguns that sold for $12. These types of barrels earned a reputation for weakness and were never meant to be used with modern smokeless powder, or any kind of moderately powerful explosive. Because of the resemblance to Damascus steel, higher-end barrels were made by Belgian and British gun makers. These barrels areproof marked and meant to be used with light pressure loads. Current gun manufacturers such as Caspian Arms make slide assemblies and small parts such as triggers and safeties for Colt M1911 pistols from powdered Swedish steel resulting in a swirling two-toned effect; these parts are often referred to as "Stainless Damascus".
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