The arms and armor section of most major museums showcase examples of Damascus steel weapons. These steels are of two different types, Damascus welding pattern and Damascus wootz, both of which apparently were produced first before around 500. These steels have in common an attractive surface pattern composed of swirl patterns of the regions of light engraved on an almost black background The welding pattern steels were produced by forging blades alternating welding of high and low carbon steels. Then, this composite material is bent and welded-together, and the folding / forging cycle was repeated until a large number of layers were obtained.This article refers to the second type of steel from Damascus, sometimes called eastern Damascus. The most common examples of these steels are swords and daggers, although examples of the body armor are also known. The name of Damascus apparently originated with these steels. The steel itself was not produced in Damascus, but in India and became known in English literature in the early 19th century as the wootz steel, as it is referenced here. Detailed images of many of these Wootz Damascus swords are presented in Figiel's book, and the metallurgy of these plates is discussed in Smith's book.Unfortunately, the technique of Damascus wootz steel sheet production is a lost art. The date of the last sheets produced with the highest quality damascene patterns is uncertain, but it is probably around 1750; It is unlikely that the leaves showing low quality damascene patterns were produced later than the beginning of the 19th century. The debate has persisted in the metallurgy community for the past 200 years as to how these shovels were made and why. what the surface pattern appeared. Research efforts in recent years have claimed the discovery of methods to replicate Damascus Wootz steel sheets, but all these methods suffer from the same problems today in blacksmiths They have been unable to use the methods of reproducing the blades. The successful reproduction of the Damascus wootz blades requires that they can produce blades that conforms to the chemical composition, possesses the characteristic damascene surface pattern, and possess the same internal microstructure that makes the surface pattern.
Damascus steel
Wootz steel was produced as approximately 2.3 kg of ingots, commonly known as cakes, which solidify in a closed crucible. It was a relatively high purity iron steel with 1.5% carbon. The cakes were sent to Damascus, Syria, where the blacksmiths learned to give them the shape of swords that show a beautiful surface pattern. The hypereutectoid carbon level of these steels plays a key role in the production of the characteristic surface pattern, because the pattern resulting from the alignment of Fe3C particles that form in such steels when cooling. When Western Europeans first found these stamped weapons, they adopted the name Damascus Steel. Damascus wootz blades that possess the highest quality damascene patterns were produced in the 4th century.Both the internal micro structure and the chemical composition of these steels were well established early in this century. The internal micro structure of a Damascus wootz blade that possesses a high-quality damascene surface pattern is a unique metallurgical micro structure. It consists of bands of small particles (generally about 6 mm in diameter) of Fe3C (cementite) grouped along the centerline of the band. The bands have a characteristic spacing in the range of 30-70 mm and are contained in a steel matrix. The structure of the steel matrix varies depending on how the smith heat treated the blade, but is generally found to be pearlite. The bands are parallel to the plane of the forge of the blades. By manipulating the angle of the blade surface with respect to the plane of the bands, the blacksmith can produce a variety of intricate patterns of intersection of the bands with the surface of the blade. With polishing and chemical etching, the Fe3C particles cause the bands that appear white and the matrix of almost black steel; In this way, the surface pattern is created.
The reproduction of the Wootz Damascus blades
In a recent work, a technique to produce sheets that respond to the best Wootz blades with Damascus museum quality, both in the superficial aspect and the internal microstructure has been developed. It has been specially prepared to include the famous Muhammad ladder pattern that appears on many of the swords and blades of higher quality museums. The circular pattern between ladders is often called the Rose pattern, and is also sometimes found in high-quality museum blades. A longitudinal section of an adjoining piece of this blade is also shown, illustrating the aligned bands of Cementite particles in cluster typical of the best quality museums shovels.A detailed picture description of the production process of this sheet has been recently published. In addition, the technique has been fully described in the literature, and it has been shown that leaves with high quality damascene patterns can be produced Repeatedly Using the technique. The technique is, in essence, a simple reproduction of the general method described by previous researchers. A small steel ingot of the correct composition (Fe + 1.5C) is produced in a closed crucible and then forged into a leaf shape. However, some key factors are now defined. These include the time / temperature record of the ingot preparation, the temperature of the forging operations, and the level of type and composition of the impurity elements in Fe + 1.5C steel. It seems that the most important factor is the type of impurity elements in the steel ingot. Recent work has shown that bands of Fe3C particle grouts can be produced on the blades by the addition of very small amounts (0.03% or less) of one or more carbide-forming elements, such as V, Mo, Cr, Mn, and Nb. The vanadium and molybdenum elements seem to be the most effective elements in the cause of band formation to occur. An obvious question posed by these results is, are these elements also present at low levels in the Damascus Wootz 16-18 century blades?
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