Damascus Steel

Damascus steel was a type of steel used in Middle Eastern swordmaking. Damascus steel was created from wootz steel, a steel developed in India around 300 BCE. These swords are characterized by distinctive patterns of banding and mottling reminiscent of flowing water.

Such blades were reputed to be tough, resistant to shattering and capable of being honed to a sharp, resilient edge. The original method of producing Damascus steel is not known. Recreating Damascus steel is a subfield of experimental archaeology. Many have attempted to discover or reverse-engineer the process by which it was made.

The reputation and history of Damascus steel has 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. Although modern steel outperforms these swords, microscopic chemical reactions in the production process may have made the blades extraordinary for their time. Woody biomass and leaves are known to have been used to carbonize the Wootz ingots used in Damascus steel, and research now shows that carbon nanotubes can be derived from plant fibers, suggesting how the nanotubes were formed in the steel. Some experts expect to discover such nanotubes in more relics as they are analyzed more closely.

Historians state that the original damascus steel 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. 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.

Pattern welding (forming a blade from of several metal pieces of differing composition that are forge-welded together) produces surface patterns similar to those found on Damascus blades, and is sometimes called ‘Modern Damascus.’ Such blades are 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, which 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 a smith must forge a damascus blade with a minimum of 300 layers.

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 wootz steel 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 (near molten) state, with a grain structure and beads of pure iron carbide which were the result of its hypereutectoid (high carbon alloy) 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 (iron) and cementite (iron and carbon) 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.

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 Turkestan, 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.

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 (rod). This process was referred to as ‘laminating’ or ‘Damascus,’ and 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 are proof 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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