Talk:Damascus steel

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  • "On the cutting edge." (March 25, 2004). Clovis News Journal. [1].

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[edit] Innaccurate Sentence

Having owned a couple wootz knives, I have to dispute this line --"allowing the swordsmith to make an edge centered on one of the carbide bands and thus very strong, while the sword as a whole remained flexible as in normal steels." The bands are very fine and often flow in many directions, anyone that has actually handled wootz or seen a detailed photo can verify that. While the banding can be controlled and even made very coarse, I have never heard of attempting to make them wide enough that one could center the edge on a single band, nor have I seen such a thing in any of the dozens of pictures of museum quality wootz swords I've seen. The sentence as stated gives the impression that wootz worked something like san-mei, which is incorrect, as the wootz' steel matrix is virtually homogenius in hardness regardless of the carbide density of a particular band. ~Nick 12/1/05

[edit] Contradictory Paragraph

I removed a paragraph under Types of Damascus because it contained information that was contrary to the information above it in the article. However I am not knowledable on the subject and it would be best if someone who is would take a look at this. optimistic-x 21:15, 13 November 2005 (UTC)

[edit] Removed content

I have removed this edit. It was evident that it was made without regard to the rest of the article. -- Egil 23:36, 10 September 2005 (UTC)

Maybe Egil will share with us some of his experience as a bladesmith. Rktect 03:26, September 11, 2005 (UTC)
Perhaps rktect too. -- (☺drini♫|☎) 01:49, 26 September 2005 (UTC)

[edit] Disputed

The dispute is with regards to this and this edit, or any future edits to the same effect. The editor, User:rktect, edits this excellent article totally without regard to its current structure and content. He also adds his usual irrelevant and/or self-invented connections to ancient Egypt. His description of the process is also different from the process described in the original article, as is the claim that the actual steel came from India. Regretfully, the only immediate means available seems to be adding a dispute tag. (If someone can tell me of a better way, please do) -- Egil 10:52, 11 September 2005 (UTC)

Egil should read the sources cited, maybe look up the word wootz. Since its clear he lacks even the most rudimentary comprehension of the subject matter and is unaware that Damascus steel is a technique rather than a material the disputed tag should be removed.

As to the Egyptian involvement, the earliest known references to iron working come from Egypt. Both the Egyptians and Hitties made small tools of high carbon low temperature iron which they hammered and folded repeatedly to strengthen. Each fold doubles the number of layers. By the time of the battle of Kadesh, c 1285 BC the use of iron had expanded from small tools to the mass produced rims of tens of thousands of chariots.

The difference between iron and steel is the addition of small amounts of other elements, Carbon, Manganese, Silicon, Chromium, Vanadium and Molybdenum to mention just a few of the more common ones. The carbon comes from the charcoal the iron is heated in. Other elements can be added as a twist of wire that gets distributed by repeated hammering and folding.

In the case of wootz what made it special was that iron ore was slow baked in a clay crucible filled with legumes whose ability to fix nitrogen in nodules in their root system made it ideal for nitriding the wootz.

The most important thing about Damascus steel is the alternation between the different forms of steel so that cementite, pearlite, martensite and austenite are distributed to exactly where they need to be so that for example the center of the edge of a blade can be high carbon steel that is hard and sharp and can hold an edge but the outside of the edge can have a lower carbon content making it less brittle and tougher so it is resistent to chipping.

The rolled edge used in Damascus steel blades does away with the cantle or chine of the edge which can weaken the blade. Rolled edges are nearly impossible to acheive in mass production so all of the best blades are hand polished with ten or more successive grits. Rktect 17:48, September 11, 2005 (UTC)

the center of the edge of a blade can be high carbon steel that is hard and sharp and can hold an edge but the outside of the edge can have a lower carbon content making it less brittle and tougher so it is resistent to chipping.
I was under the impression that the opposite was the goal; the main body of the blade constructed of softer, more malleable steel to resist breakage with the blade edge of a harder, more brittle steel for sharpness and durability. --Bk0 18:36, 11 September 2005 (UTC)
[San Mei] Yes and no. In refering to the center of the edge we are looking at that portion of the hamon outboard of the nioi. The Vikings for example used low carbon cores and high carbon surface layers. The idea was that the cutting edge should be made hard and sharp but the rest of the blade will remain flexible.
The problem with that simplistic model is that if sharpening the edge removes the hard outer layer it leaves the soft core exposed. In many cases that would be true for early not particularly high quality or mass produced blades. Higher quality hand made blades paid more attention to what was going on with the edge in the art of the swordsmith as well as that of the sharpener. In many eastern blades nitrided wootz was used. In Japanese blades an additional sandwich of layers occurs in the hamon.
[hamon]
"The Hamon may be in an infinite variety of patterns, but appears as a milky white colour on a properly polished blade. The upper edge of the Hamon will be formed from tiny martensite crystals called Nie. Sometimes these are too small to see with the naked eye and are then known as Nioi. It is Me and Nioi that border the Hamon and form the pattern of the Hamon and they should be examined very closely, ideally by holding the blade at eye level, ideally pointed towards a spotlight. The Nioi- guchi (line of the Hamon) should form an unbroken and constant line from the Machi area (bottom of the blade) along its entire length. A break in the Hamon, called Nioi-giri is a serious flaw and should be avoided. It is also important that the Boshi (the area of the Hamon within the Kissaki) does not disappear off the edge. This is also a serious flaw in the blade and is only acceptable on great swords of historical and cultural significance! No compromise should be accepted here."
[clive sinclair]

Rktect 23:42, September 11, 2005 (UTC)


I think much of the argument here has to do with the confusion with the term "Damascus steel" itself. Pattern welded damascus, which as accomplished by folding low and high carbon steel together at "yellow hot" temperatures, has existed for many millenia (since Viking times) in numerous cultures. Wootz damascus is completely different and accomplished by directly hammering the Indian ingots into blades at a relatively cool "red hot" temperature. The pattern formed in the wootz blades is a result of segragated cementite particles unevenly distributed in the blade.
The Indian ingots themselves play an important role through both it composition and its manufacturing process. While I'm not sure about the whole "nitrating" deal you said about the wootz cake, vegetation was added to increase hydrogen content in the crucibles to decrease ingot brittleness. The ore is also important due to high vanadium impurities which serve to promote cementite formation. Smelting crucible are allowed to cool gradually such that dendretic formations form in the ingot, which concentrate the vanadium impurities into bands. These bands are where the cementite particles will form, and is amplified in the "red hot" hammering process. By the way the main difference between steel and iron definitely not due to metallic impurities but rather due to carbon content alone.
As for what I think should be done with this article, I suggest splitting it into Pattern welding and Wootz. "Damascus steel" should become a disambiguation page, as the term clearly seems to be the problem. -- Sjschen 04:07, 25 September 2005 (UTC)
Just to add, the creation of pattern welded damascus steel resulted ia an effort by people to emulate wootz damascus after the latter's manufacturing technique has been long forgotten. -- Sjschen 04:11, 25 September 2005 (UTC)
I agree that for a long time outside of india the effect of the slow low temperature fixing of the alloying elements in wootz to include carbon, nitrogen, hydrogen, vanadium, nickle, etc was neglected. On the other hand I don't know of any Damascus that was made of one grade of iron or steel without the process of combination through the arrangement of different grades of iron to include both wootz and in some cases meteoric iron with high nickle content. In addition to the use of wootz its really the ability to determine the placement of the Cementitie, Pearlite, Martinsite and Austenite through the hammerering, quenching, tempering and forging in the charcoal fire that adds the high carbon to make the iron into steel as a combination of the materials and methods that we associate with Damascus that makes Damascus steel what it is. The idea that pattern welded steel is inferior to true Damascus made with wootz would certainly require a lot of disambiguation. Rktect 13:39, 25 September 2005 (UTC)

[edit] Pattern welding was never lost

The term "Demascus steel" comes from the city of Demascus. Wootz is an Old English and a term for crucible steel. According to professional blade smith and author Dr. Jim Hrisoulas Pattern Welding was never lost. I agree that this article should be split into Wootz and Pattern Welded Steel.

But pattern welding != Damascus steel. They produce visually similar results, but they are radically different structurally, and are produced by (as well as can be told) radically different techniques. Pattern welding and folded steel forges dissimilar alloys of steel at supercritical temperatures, while, according to Pendray, the best reproductions of true Damascus made blades from Indian wootz are made by cold working the wootz ingots at just below the critical temperature, which causes the coarse grained annealed wootz to work harden. By notching the surface of the ingot, variations in stretching can be obtained, which if cone correctly can produce distinct patterns in the blade, such as the famed "Mohammed's ladder". What the article really needs is a breakdown into pattern welded steel, the modern "Damascus" that the knifemakers use, and the true ancient "Damascene steel", which was a special super-high carbon, cold forged, low alloy steel. scot 16:38, 19 December 2005 (UTC)

[edit] Comment from user User:Jsmasangkay

"Mokume-gane should be spelled moku-megane. Moku-megane comes from 2 Japanese words, moku meaning wood, lumber, timber etc. and megane meaning eyeglasses. The literal translation would be "wood eyeglasses", however the most popular translation is "wood eye"." I'll look into this and see if there's a consensus. scot 20:53, 31 March 2006 (UTC)

On google I get 115,000 hits on "mokume-gane" vs. 806 hits for "moku-megane". There's also a mokume-gane article here, but no moku-megane. If you can provide an independent source for the translation argument, then it should probably go in the mokume-gane article, and have a moki-megane redirect created. scot 21:05, 31 March 2006 (UTC)


[edit] Question

I have heard that Damascus steel was quenched in the bodies of live slaves or prisoners by the original metalsmiths, presumably creating a unique molecular effect that gave the blades their astounding capabilities. Presumably the Europeans used cows and later found pigs to be even better for duplicating these alloys. Is there any evidence to support this?

A body would not be a particularly good quenching medium; the blade comes out of the fire at the critical temperature (which, as I recall, is just over 1400F for high carbon low alloy steel) and has to be dropped at a controlled rate to acheive the desired hardening. The preferred mediums for high carbon low alloy steels are water and oil (olive oil is highly recommended due to the high flash point). The goal is to fix the structure of the steel quickly, to form the high hardness martenzite, and then the blade would be heated back up to a sub-critical temperature (600F or higher) to temper the steel and draw the hardness back to the desired balance of hardness and toughness. If the blade is cooled too slowly, the residual heat from the core of the blade will prematurely temper the steel, and can result in soft spots. The most common cause of a bad quench is too little quenching medium; there's a whole lot of heat to transfer, and if there's not enough water or oil to immerse the blade (and some of the quench medium is going to flash boil off) then the blade won't cool evenly. The blade is also moderately soft coming out of the heat treating furnace; it's very easy to bend the blade, and there's no springiness in the steel at that temperature. Trying to plunge a blade into a body would first warp the blade (it's nowhere near sharp until after hardening and grinding, so you'd have to push hard), the high heat of the blade would cauterize the wound and prevent any additional body fluids from leaking in to cool the blade further, so the blade would cool very poorly.
Now one thing I have seen in a reputable source on Japanese swordsmithing, is the use of the bodies of executed criminals to test finished blades. The bodies would be stacked up and the sword would be used to cut through as many bodies as possible. In fact, there is a standardized method for taking a rolled up reed mat, soaked in water, of a certain diameter and using it as a "body substitute", much like ballistic gelatin is used for terminal ballistics testing today. This link[2] describes the process, and corresponds to what I remember from the swordsmithing book. scot 14:27, 26 April 2006 (UTC)

[edit] Rediscovery

According to this article [3], it's been rediscovered. -- LGagnon 19:23, 5 July 2006 (UTC)

That's a rehash of Verhoeven and Pendray's "hot cold forging" work covered in the "Attempts at reproduction" section. No one can definitively say "the process has been rediscovered" because no one knows what the original process was. What can be said is that Verhoeven and Pendray's steel is a very close match to the original Damanscus blades, and so the process is equivalent, and potentially the same. scot 19:37, 5 July 2006 (UTC)

[edit] AD/CE

I don't see the point in switching this article to an AD/BC orientation for dates, since it largely covers material about the non-Christian world (Damascus, Syria, India). Since I was alerady going to make some other edits, I went ahead and reverted it to BCE/CE this time. Thoughts of others? -- nae'blis (talk) 15:10, 6 July 2006 (UTC)

makes sense. Jerdwyer 04:57, 1 September 2006 (UTC)

[edit] "origin of the word damask

I removed the sentence saying that the swirling patterns was "apparently the origin of the word damask." The OED says the etymology of the word damask is "originally coming from Damascus." I.e. damask and damascus steel have the same root, and one is not the root of the other. Jerdwyer 05:15, 1 September 2006 (UTC)

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