Damascus steel

For Damascus Twist barrels, see Skelp. For the album of the same name, see Damascus Steel (album).

Close-up of a 16th century Iranian crucible forged Damascus steel sword

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 BCE to 1700 CE. 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.^[1] 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.^[2][3]

The reputation and history of Damascus steel has given rise to many legends, such as the ability to cut through a rifle barrel, or cut a hair falling across the blade.^[4] No evidence exists to support such claims. But a research team in Germany published a report in 2006 revealing nanowires and carbon nanotubes in a blade forged from Damascus steel,^[5] which was promptly covered both by National Geographic^[6] and the New York Times.^[7] Whatever the lost methods of making Damascus steel, of ore refinement and forging, they harnessed impurities and changes at the molecular level. Although modern steel outperforms these swords, the microscopic chemical reactions may have made the blades extraordinary for their time. Other experts are unsurprised, and expect to discover such nanotubes in more and more relics as they are looked at more closely.^[8][6]

Etymology

Several theories on the origins of the term "Damascus steel" exist, but none of them may be confirmed definitively.^[9] 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.^[10]
• The name of the swordsmith. For instance, the author al-Beruni refers to swords made by a man he names Damashqi.^{[citation needed]}
• The comparison of the patterns found on the swords to Damask fabrics woven in the Byzantine empire.^[10]

History

A bladesmith from Damascus, ca. 1900

Historians such as Hobson, Sinopoli, and Juleff state that the material used to produce the original damascus was ingots of Wootz steel, which originated in India and Sri Lanka^[11] and later spread to Persia.^[12] From the 3rd century to the 17th century, India was shipping steel ingots to the Middle East for use in Damascus steel.^[13]

In Europe, research has demonstrated that high quality swords with damask patterns were produced by various pattern welding techniques since at least the 3rd century BCE by the Celts and Germanic peoples.^[14]

Loss of the technique

The process was lost to metalsmiths after production of the patterned swords gradually declined and eventually ceased circa 1750. 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.^[2][3][15]

The raw material for producing the original Damascus steel is believed to be wootz imported from India.^[2][3] 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.^[2] 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.^[2][3]

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.^[15]

Reproduction

Recreating Damascus Steel is a one subfield of Experimental archaeology. Many have attempted to discover or reverse-engineer the process by which it was made.

Moran: billet welding

Close-up of a "modern damascus" (pattern welded) fixed blade

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 a pattern welding 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' Guild Show.^[16][17] This "Modern Damascus" is made from several types of steel and iron slices, which are then welded together to form a billet.^[18] The patterns vary depending on how the smith works the billet.^[17] The billet is drawn out and folded until the desired number of layers are formed.^[17] 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.^[19]

Verhoeven and Pendray: crucible

J. D. Verhoeven and A. H. Pendray published an article on their experiments on reproducing the elemental, structural, and visual characteristics of Damascus steel.^[2] Verhoeven and Pendray 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 state, with a grain structure and beads of pure iron carbide which were the result of the hypereutectoid state of the wootz. Verhoeven and Pendray had already determined that the grains on the surface of the steel were grains of iron carbide, so their question was how 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 destroy the pattern permanently. However, Verhoeven and Pendray discovered that in samples of true Damascus steel, the Damascene pattern could be recovered by aging at a moderate temperature. Their investigations found that certain carbide forming elements, one of which was vanadium, did not disperse until higher temperatures than those needed to dissolve the carbides. Therefore, though a high heat treatment could remove the visual evidence of patterning associated with carbides, it 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

The Russian bulat steel has many properties in common with Damascus steel. Ironically the process for producing bulat is also lost. Pavel Petrovich Anosov made several attempts to recreate the process in the mid-19th century. Wadsworth and Sherby also researched ^[3] 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^[20] and carbon nanotubes.^[21] Peter Paufler, a member of the Dresden team, says that these nanostructures are a result of the forging process.^[22][6]

Sanderson proposes that the process of forging and annealing accounts for the nano-scale structures.^[22]

Damascus steel in gunmaking

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.^[23][24] This process was referred to as "laminating" or "Damascus" and these barrels were found on shotguns that sold for $12.^[23][24] These types of barrels earned a reputation for weakness and were never meant to be used with modern smokeless powder, as well as any kind of moderately powerful explosive.^[24] Because of the appearance to Damascus steel, higher-end barrels were made by Belgian and British gun makers.^[23][24] These barrels are proof marked and meant to be used with light pressure loads.^[23] 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".^[25]

See also

• Experimental archaeology
• Tungsten carbide
• Kris

References

1. ^ Figiel, Leo S. (1991). On Damascus Steel. Atlantis Arts Press. pp. 10–11. ISBN 9780962871108. 
2. ^ ^{a b c d e f} J. D. Verhoeven, A. H. Pendray, and W. E. Dauksch (1998). "The key role of impurities in ancient damascus steel blades". Journal of Metallurgy 50: 58. http://www.tms.org/pubs/journals/JOM/9809/Verhoeven-9809.html. 
3. ^ ^{a b c d e} Jeffrey Wadsworth and Oleg D. Sherby (1980). "On the Bulat – Damascus Steel Revisited". Prog. Mater. Sci. 25 (1): 35–68. doi:10.1016/0079-6425(80)90014-6. 
4. ^ Becker, Otto Matthew (1910). High-speed steel: the development, nature, treatment, and use of high-speed steels, together with some suggestions as to the problems involved in their use. New York: McGraw-Hill book company. pp. 10–14. 
5. ^ Reibold, M.; Paufler, P.; Levin, A. A.; Kochmann, W.; Pätzke, N.; Meyer, D. C. (2006). "Materials: Carbon nanotubes in an ancient Damascus sabre". Nature 444 (7117): 286. doi:10.1038/444286a. PMID 17108950. 
6. ^ ^{a b c} Legendary Swords' Sharpness, Strength From Nanotubes, Study Says. News.nationalgeographic.com (2010-10-28). Retrieved on 2011-11-13.
7. ^ Fountain, Henry. (2006-11-28) Nanotechnology in Sabres From Damascus, a New Look at the Seafloor and Predicting Reef Damage – New York Times. Nytimes.com. Retrieved on 2011-11-13.
8. ^ K. Kris Hirst [http://archaeology.about.com/od/ancientweapons/a/damascus_steel_2.htm Damascus Steel. Nanotechnology and Sword Making]. Archaeology.about.com (2010-06-10). Retrieved on 2011-11-13.
9. ^ Williams, Alan R. (2003). The knight and the blast furnace: a history of the metallurgy of armour in the Middle Ages & the early modern period Volume 12 of History of warfare. BRILL. pp. 10–14. ISBN 9789004124981. 
10. ^ ^{a b} Goddard, Wayne (2000). The Wonder of Knifemaking. Krause. pp. 107–120. ISBN 9780873417983. 
11. ^ G. Juleff (1996). "An ancient wind powered iron smelting technology in Sri Lanka". Nature 379 (6560): 60. doi:10.1038/379060a0. 
12. ^ Hobson, John M. (2004). The Eastern Origins of Western Civilisation. Cambridge University Press. p. 85. ISBN 0521547245. 
13. ^ Sinopoli, Carla M. (2003). The Political Economy of Craft Production: Crafting Empire in South India, c. 1350–1650. Cambridge University Press. p. 192. ISBN 0521826136. 
14. ^ Stefan Mäder: "Stähle, Steine und Schlangen. Zur Kultur- und Technikgeschichte von Schwertklingen des frühen Mittelalters", dissertation, Berlin 2001, pp. 275–282
15. ^ ^{a b} Lionel Milgrom (2009). "Carbon nanotubes: Saladin's secret weapon". http://www.rsc.org/chemistryworld/News/2006/November/15110602.asp. 
16. ^ Lewis, Jack; Roger Combs (1992). Gun digest book of knives. DBI. pp. 58–64. ISBN 9780873491297. 
17. ^ ^{a b c} Kertzman, Joe (2007). Art of the Knife. Krause Publications. pp. 224–226. ISBN 9780896894709. 
18. ^ Loveless, Robert; Richard Barney (1995) [1977]. How to Make Knives. Knife World Publications. p. 169. ISBN 0-695-80913-X. 
19. ^ "ABS Testing Rules and Guidelines for the Master Smith Rating" (PDF). http://www.americanbladesmith.com/uploads/file/Testing/MS%20Test%20FINAL%204-24-2010.pdf. Retrieved 2011-03-12. 
20. ^ Kochmann, W.; Reibold, Marianne; Goldberg, Rolf; Hauffe, Wolfgang; Levin, Alexander A; Meyer, Dirk C; Stephan, Thurid; Müller, Heide et al. (2004). "Nanowires in ancient Damascus steel". Journal of Alloys and Compounds 372: L15–L19. doi:10.1016/j.jallcom.2003.10.005. ISSN 0925-8388. 
    Levin, A. A.; Meyer, D. C.; Reibold, M.; Kochmann, W.; Pätzke, N.; Paufler, P. (2005). "Microstructure of a genuine Damascus sabre" (PDF). Crystal Research and Technology 40 (9): 905–916. doi:10.1002/crat.200410456. http://www.crystalresearch.com/crt/ab40/905_a.pdf. 
21. ^ Reibold, M.; Paufler, P; Levin, AA; Kochmann, W; Pätzke, N; Meyer, DC (November 16, 2006). "Materials:Carbon nanotubes in an ancient Damascus sabre". Nature 444 (7117): 286. Bibcode 2006Natur.444..286R. doi:10.1038/444286a. PMID 17108950. 
22. ^ ^{a b} K. Sanderson (2006). "Sharpest cut from nanotube sword". Nature 444: 286. doi:10.1038/news061113-11. 
23. ^ ^{a b c d} Simpson, Layne (2003). Shotguns & Shotgunning. Krause Publications. p. 256. ISBN 978-0873495677. 
24. ^ ^{a b c d} Matunas, Edward A. (2003). Do-It-Yourself Gun Repair. Woods N' Water Inc.. p. 240. ISBN 978-0972280426. 
25. ^ Hopkins, Cameron (2000). "Damascus Knight .45". American Handgunner Magazine 20 (4): 128. 

Further reading

• Eric M. Taleff, Bruce L. Bramfitt, Chol K. Syn, Donald R. Lesuer, Jeffrey Wadsworth, and Oleg D. Sherby, "Processing, structure, and properties of a rolled ultrahigh-carbon steel plate exhibiting a damask pattern," Materials Characterization 46 (1), 11–18 (2001).
• J. D. Verhoeven, "A review of microsegregation induced banding phenomena in steels", J. Materials Engineering and Performance 9 (3), 286–296 (2000).

External links

• "Damascene Technique in Metal Working"
• "The Mystery of Damascus Blades"
• "Secret's out for Saracen sabres"
• "Damascus Gun Barrels"
• Damascus Steel: Archaeology
• "Technical Report"