Metallurgy - Availability and Alternatives of Elements
After a rather extensive (yet amateurish) bout of research into the various alloys of steel, I compiled a list of those elements which are of the most use in swordsmithing. The list, below, includes the elements principle function in alloying, the date at which it was discovered and the source from whence it is most often derived.

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Aluminum is widely used as a deoxidizer. Aluminum is the most effective alloy in controlling grain growth prior to quenching. First referred to in 1808 by Humphry Davy. Most prevalent within bauxite ore, rarely occurs freely in nature, save within volcanic mud deposits.

Boron is added to improve hardenability. Boron inclusion generally falls within a range of 0.0005 to 0.003%. Whenever boron is substituted for other alloys, it should be done only with hardenability in mind. First identified by Jöns Jakob Berzelius in 1824, though it was earlier isolated in 1808 by Humphry Davy. Derived primarily from borax.

Carbon is the primary hardening element in steel. Hardness and tensile strength increase alongside carbon content, up to about 0.65% carbon alloy (65 points), at which the maximum is achieved. Beyond that, and up to 150 points, the addition of further carbon serves solely to increase wear resistance, whilst contributing to an increase in brittleness. Ductility decreases proportionally with increasing carbon content. Known since prehistory in the forms of charcoal and coal, particularly anthracite.

Chromium is commonly added to steel in order to increase corrosion resistance, hardenability and oxidation resistance, in addition to improving high-temperature strength. Most chromium-bearing alloys contain 0.50 to 0.90 percent chromium. As a hardening element, chromium is frequently used with a toughening element such as nickel. At higher temperatures, chromium contributes to increased hardness. In large amounts, chromium creates rather brittle steel, which can cause the alloy to crack during tempering. Known as early as the 3rd century, having been used to coat bronze weapons during the Qin Dynasty in China. Commercially mined as both crocoite and chromite ore.

Copper is added at the smiths discretion in traces amounts to improve the alloys resistance to atmospheric corrosion. Amounts added for this purpose generally range between 0.15 to 0.25 percent, when seen at all in swords. This element, however, is not always included as it is detrimental to the surface quality, hardness and tensility of the blade. Dates back to at least 8700 BC. Found freely in nature, uncombined with other elements.

Manganese is generally beneficial to the surface quality of steel, especially in re-sulfurized steels. Manganese is present to some degree in all steel, generally between 0.50 to 1.50 percent. It is important in the manufacturing of steel as it deoxidizes such. It also contributes to the strength and hardness, but far less than carbon. Increasing the manganese content decreases ductility but, again, less than carbon. Manganese has a significant effect on the hardenability of steel, primarily during the heat-treatment process, as it lowers the temperature at which martensite is formed during quenching. Known as far back as ancient Egypt, Rome and Greece, where it was dubbed "magnes" (later known as magnesia), which has since come to be known as pyrolusite (manganese dioxide), the most common of its forms.

Molybdenum increases the hardenability of steel. This element, especially between the limits of 0.15 and 0.30 percent, minimizes the susceptibility of steel to temper embrittlement. Alloys containing this element, however, must be tempered at a higher temperature. Molybdenum retards the transformation of austenite to pearlite far more than it does the transformation of austenite to bainite, hence bainite can be produced by continuous cooling of molybdenum-containing steel alloys. Extracted primarily from molybdenite, which was once known as molybdena, it was first isolated as a separate element in 1778 by Carl Scheele. The first recorded use of molybdenum to alloy steel was in 1894, by the Schneider Electrics company in creating armor plating.

Nickel is a ferrite strengthener, generally seen in quantities between 0.90 and 2.10 percent. Nickel does not form carbides in steel, thereby toughening the ferrite content of the base alloy. Nickel increases the impact strength of steel, particularly when used in combination with chromium. It has no appreciable affect on hardenability. Unintentionally utilized as far back as 3500 BC, having oft been mistaken for silver. In medieval times, it was primarily derived from nickeline, named Kupfernickel by the Germans who discovered it.

Niobium (aka Columbium) increases the yield strength and, to a lesser degree, the tensile strength of steel. It does, however, decreases the hardenability of steel by absorbing some of the carbon. Discovered in 1801 by Charles Hatchett from a mineral sample mined in 1734. Found within pyrochlore, the main source for niobium, and columbite

Phosphorus increases strength and hardness, while decreasing ductility and notch impact toughness. The adverse effects on ductility and toughness are greater in tempered high-carbon steel. Phosphorous levels are normally maintained at low levels. The first form to be isolated (white phosphorus) was in 1669, although speculation dates its initial discovery back to ancient Rome. While commonly found in all manner of phosphate rocks, as calcium phosphate, it was initially obtained from bone ash residue and urine.

Silicon is one of the principal deoxidizers, the amount present generally ranging between 0.1 and 0.25 percent. The ratio decreases, most often, when other deoxidizers are used. Silicon is less effective than manganese at increasing hardness, however, it does so without any loss in ductility. Originally identified as a unique element by Antoine Lavoisier in 1787, although it was in use by various earlier cultures. Pure silicon crystals are rarely found in nature, save within the occasional gold and volcanic deposit, hence the element is most often derived from quartz and sand (as silicon dioxide).

Sulfur decreases ductility and impact toughness, especially in the transverse direction. Sulfur content is normally maintained at low levels in swords, between 0.1 and 0.6 percent, as it improves machineability. Known to early civilizations, including the Israelites and Chinese, as evidenced by its inclusion in the Pentateuch, wherein it was commonly translated and referred to as brimstone. Elemental sulfur is found near hot springs and volcanoes, while it may also be derived from any of the many sulfide and sulfate minerals (pyrite and gypsum respectively).

Titanium is used to retard grain growth and thus improve toughness. Discovered by William Gregor in 1791. Cannot be created in its elemental state by reduction with carbon, as it forms titanium carbides, the most modern method of creating such having been invented in 1910.

Tungsten (aka Wolfram) provides for a longer-lasting edge, yet renders the alloy difficult to forge. First isolated from its primary ores - wolframite and scheelite - in 1781 and later 1783, it is derived by reducing the resultant acid of each ore through charcoal.

Vanadium increases the yield and tensile strength of an alloy, by inhibiting the grain growth of steel. Up to amounts of 0.10 percent vanadium also increases the hardness of the alloy, although any further addition reduces the hardenability. Originally named erythronium by Andrés Manuel del Río, who discovered it in 1801. Metallic vanadium is not found in nature, yet it occurs in sixty-five distinct minerals. It is most often obtained from magnetite, although historically vanadinite served as the principal source. Vanadium is toxic.

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...taking all this into account, my inquiry relates to the availability and/or alternatives of/for such metals to the medieval smith (think, High to Late Middle Ages era). Now, obviously, many of those listed are impossible for the medieval smith (and most modern ones) to obtain on their own (reduce from ores, not order), including boron, molybdenum, niobium, titanium, tungsten and vanadium. For those, I wonder if anyone is aware of antiquities that include said elements (particularly those in which they are accepted to have been deliberately fashioned with), any manner in which a medieval smith might have conceivably acquired some, or alternatives by which they may have come to be included in a sword? By the latter, I mean, is there any chance that medieval smiths might have known some of the aforementioned under a different name (as with manganese) or inadvertently added them to their steel while in the process of alloying it with other elements (as, for example, using certain sulfides can lead to the inclusion of copper or silicon). For the rest, I would like to know how the typical medieval smith went about creating alloys with them? I mean, I can hardly see someone digging up a chunk of copper and just throwing it in the mix.
While a pointed response would be greatly appreciated, any recommendations of pertinent reading material would leave me equally obliged. Having said as much, if at all possible, online material would be best, as my hometown does not have a bookstore and the nearest library is roughly fifty-miles away.
Thanks...
Regarding medieval metallurgy:

You need to get your hands on The Knight and the Blast Furnace: A History of the Metallurgy of Armour in the Middle Ages & the Early Modern Period and read as many articles by Dr. Alan Williams as you can.

You may also be interested in Arms, Armour and Base-Metalwork by Claude Blair, though I don't know much about this title other than I'd like to get myself a copy. It may be not be on-topic at all.

One of our articles may be of interest to you as it briefly discusses the craft of making swords: (check out its bibliography)

[ Linked Image ]
Sword Blade Hardness: the current research
An article by Craig Johnson

Another article by Craig Johnson can be found at the Oakeshott Institute, Some Aspects of the Metallurgy and Production of European Armor.


Perhaps none of these are directly related to your topic but can provided needed context.


Medieval swordmaking was often more mystery and magic than science. This is likely more true regarding the specific materials used than any other component. Successful smiths often found success simply because of their close proximity to material deposits that already naturally existed and were easily obtainable. Antiques show all kinds of variety both in the materials contained in them and the mixture of them.
Impressive. There are a few metallurgical people floating around here (Jeroen) who should be able to give you some nice feedback.

I still need to get a copy of the Knight and the Blast Furnace.

M.
Re: Metallurgy - Availability and Alternatives of Elements
Orion Graye wrote:
Chromium is commonly added to steel in order to increase corrosion resistance, hardenability and oxidation resistance, in addition to improving high-temperature strength. Most chromium-bearing alloys contain 0.50 to 0.90 percent chromium. As a hardening element, chromium is frequently used with a toughening element such as nickel. At higher temperatures, chromium contributes to increased hardness. In large amounts, chromium creates rather brittle steel, which can cause the alloy to crack during tempering. Known as early as the 3rd century, having been used to coat bronze weapons during the Qin Dynasty in China.
This is a myth actually. The swords were coated, but the coating apparently contained at most around 2% chrome, which is more an impurity then an intentional additive. (from hearsay, I don't have direct references yet).

Quote:
Nickel is a ferrite strengthener, generally seen in quantities between 0.90 and 2.10 percent. Nickel does not form carbides in steel, thereby toughening the ferrite content of the base alloy. Nickel increases the impact strength of steel, particularly when used in combination with chromium. It has no appreciable affect on hardenability. Unintentionally utilized as far back as 3500 BC, having oft been mistaken for silver.
Do you perhaps know of any examples of this? The melting point of nickel is too high for prehistoric techniques to be able to cast it, so they could only have coldworked/forged natural occuring nuggets into shapes.

Quote:
...taking all this into account, my inquiry relates to the availability and/or alternatives of/for such metals to the medieval smith (think, High to Late Middle Ages era). Now, obviously, many of those listed are impossible for the medieval smith (and most modern ones) to obtain on their own (reduce from ores, not order), including boron, molybdenum, niobium, titanium, tungsten and vanadium. For those, I wonder if anyone is aware of antiquities that include said elements (particularly those in which they are accepted to have been deliberately fashioned with), any manner in which a medieval smith might have conceivably acquired some, or alternatives by which they may have come to be included in a sword? By the latter, I mean, is there any chance that medieval smiths might have known some of the aforementioned under a different name (as with manganese) or inadvertently added them to their steel while in the process of alloying it with other elements (as, for example, using certain sulfides can lead to the inclusion of copper or silicon). For the rest, I would like to know how the typical medieval smith went about creating alloys with them? I mean, I can hardly see someone digging up a chunk of copper and just throwing it in the mix.
Well, the addition of most elements can only be done incase the metal is melted. In case the steel was made from wrought iron, the only impurities are those naturally present or entered the steel during the smelt (aside from perhaps carbon and sulfur). Now it's just recently come to my attention that crucible steel has been used in medieval times, so that includes the possibility to add other elements to the steel. Then there's the fact that elements may not have been known individually, but that doesn't exclude them from having been used to alloy metals with them. Zinc for example couldn't be made yet (as the smelting temperature is above the boiling point, so all smelted zinc vaporizes and burns when it leaves the furnace), but copper was alloyed with zinc to form brass, by melting the ore together with the copper. Then there's also the fact that the medieval metalurgist frequently did not understand properly how and why something worked. A prime example is that they didn't know yet that steel was iron with carbon added. Until fairly recent times, steel was thought to be a more pure form of iron instead.
Nathan Robinson wrote:
You need to get your hands on The Knight and the Blast Furnace: A History of the Metallurgy of Armour in the Middle Ages & the Early Modern Period and read as many articles by Dr. Alan Williams as you can.

Will do. Hopefully Amazon or the like has a copy in stock...

Nathan Robinson wrote:
You may also be interested in Arms, Armour and Base-Metalwork by Claude Blair, though I don't know much about this title other than I'd like to get myself a copy. It may be not be on-topic at all.

From the title alone, it sounds like the ideal reference. Thank you for the superb recommendation.

Nathan Robinson wrote:
One of our articles may be of interest to you as it briefly discusses the craft of making swords: (check out its bibliography) [ Linked Image ]
Sword Blade Hardness: the current research An article by Craig Johnson

Indeed, it was. That is to say, I have already read it. In fact, it was the presence of said article amongst your features that prompted me to write herein. I surmised that any site which held such information likely had some knowledgeable members amongst its forum. It's nice to see I was correct!

Nathan Robinson wrote:
Another article by Craig Johnson can be found at the Oakeshott Institute, Some Aspects of the Metallurgy and Production of European Armor. Perhaps none of these are directly related to your topic but can provided needed context.

On the contrary, you have been of immense aid and I am deeply obliged.

Jeroen Zuiderwijk wrote:
Orion Graye wrote:
... Known as early as the 3rd century, having been used to coat bronze weapons during the Qin Dynasty in China.
This is a myth actually. The swords were coated, but the coating apparently contained at most around 2% chrome, which is more an impurity then an intentional additive. (from hearsay, I don't have direct references yet).

I am quite willing to take you at your word. My own references were all based upon the work of Maurice Cotterell, whose research (inasmuch as I have been led to believe) merely concluded the reason for the lack of corrosion, never having declared that the chromium's presence was intentional. In any case, considering the rarity of elemental deposits (and the scarcity of chromite in Europe) I am willing to concede to the unlikelihood of a medieval smith having utilized such purposefully.

Jeroen Zuiderwijk wrote:
Orion Graye wrote:
Unintentionally utilized as far back as 3500 BC, having oft been mistaken for silver.
Do you perhaps know of any examples of this? The melting point of nickel is too high for prehistoric techniques to be able to cast it, so they could only have coldworked/forged natural occuring nuggets into shapes.

I believe the 3rd century reference was in regards to a dagger discovered at Ur of the Chaldees (circa 3100 BC), which contains roughly 11% nickel (T.A. Rickard, The Use of Meteoric Iron by Primitive Man). Then again, R.J. Braidwood, in his book Ancient Syrian Coppers and Bronzes, analyzed a bronze reamer excavated at Antioch which was fashioned of an alloy with roughly 2.73% nickel. He concluded that the inclusion was intentional. Leaving that aside, the use of nickel as a silver replacement dates back quite far into our history, with the creation of cupronickel coins in mints throughout the ancient Greco-Bactrian kingdom.
I would heartily recommend Samuel Rosenberg's monograph, Nickel and It's Alloys, which briefly glosses over many of these same finds and contains an exhaustive bibliography with further historical references. You can find an online copy here, in pdf format (may take a while to load, at 164 pages): http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA38...tTRDoc.pdf

Jeroen Zuiderwijk wrote:
Well, the addition of most elements can only be done in cases where the metal is melted. In case the steel was made from wrought iron, the only impurities are those naturally present or entered the steel during the smelt (aside from perhaps carbon and sulfur). Now it's just recently come to my attention that crucible steel has been used in medieval times, so that includes the possibility to add other elements to the steel. Then there's the fact that elements may not have been known individually, but that doesn't exclude them from having been used to alloy metals with them. Zinc for example couldn't be made yet (as the smelting temperature is above the boiling point, so all smelted zinc vaporizes and burns when it leaves the furnace), but copper was alloyed with zinc to form brass, by melting the ore together with the copper. Then there's also the fact that the medieval metallurgist frequently did not understand properly how and why something worked. A prime example is that they didn't know yet that steel was iron with carbon added. Until fairly recent times, steel was thought to be a more pure form of iron instead.

Indeed. I gather, then, that like Nathan you are of the opinion that "medieval swordmaking was often more mystery and magic than science," correct? I fear as much myself. In any case, thank you for your insightful responses. After M. Eversberg remarked about another medieval materials science buff, I had hoped you would join in. Again, thanks for doing so.
To conclude my rather lengthy ramble, would you (or anyone else) happen to know of a decent online copy of Georgius Agricola's De re Metallica? I had hoped it might contain some new information.
Orion Graye wrote:
I believe the 3rd century reference was in regards to a dagger discovered at Ur of the Chaldees (circa 3100 BC), which contains roughly 11% nickel (T.A. Rickard, The Use of Meteoric Iron by Primitive Man).
Ah, but that would be meteoritic iron, as that contains nickel. They wouldn't have had nickel to add it themselves.

Quote:
Then again, R.J. Braidwood, in his book Ancient Syrian Coppers and Bronzes, analyzed a bronze reamer excavated at Antioch which was fashioned of an alloy with roughly 2.73% nickel. He concluded that the inclusion was intentional.
Nickel does occur as natural impurity in copper. I don't recall having seen as much nickel as that, but 1-2% is not that rare. It may have entered with other additives as well though.

Quote:
Leaving that aside, the use of nickel as a silver replacement dates back quite far into our history, with the creation of cupronickel coins in mints throughout the ancient Greco-Bactrian kingdom.
I would heartily recommend Samuel Rosenberg's monograph, Nickel and It's Alloys, which briefly glosses over many of these same finds and contains an exhaustive bibliography with further historical references. You can find an online copy here, in pdf format (may take a while to load, at 164 pages): http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA38...tTRDoc.pdf
Thanks! I wasn't aware of the cupronickel coins. Those definately show that you could alloy copper with nickel at least with the furnace technology available. It may be that the nickel will dissolve into the copper at lower temperatures (like copper dissolves in tin at temperatures lower then the melting point of copper). I may still have some nickel plated copper around, so I could give it a try.

Quote:
Indeed. I gather, then, that like Nathan you are of the opinion that "medieval swordmaking was often more mystery and magic than science,"
I wouldn't say that. Medieval metallurgy depended a lot on experiment and understanding the variables that leads to specific results, which is basically what a lot of modern science relies on. They didn't have the theorethical background to explain things as we do, which would sometimes lead to interesting explanations, or details in the process that have no relevance to the process. In modern science we still have a lot of things where we only know that certain actions have certain results, without being able to explain exactly how it works (take medicine f.e.), but we don't call that mystery and magic either. If you read "On Divers Arts" by Theophilus f.e., it reads much like a modern technical book on metallurgy, aside from a few odd bits. He focusses more on what you need to do to get the results you want, rather then trying to explain it. There's a lot of religion involved in the writing (not unexpected as it's written by a monk), but not on the part of the metalurgical process, more focussing on the mindset of the metalworker (along the lines of to create something beautiful is to let the creative forces of god work through your hands, and bring a piece of heaven on earth).
If you want to know about steel, this book is absolutely amazing.

The Making, Shaping and Treating of Steel


It covers every part of the steel making process from creating it in a smiths forge, up thru the different era's of industrialization, and modern processes.

Here is a link to a digital version from the original 1920 version from Carnegie Steel (later US Steel), but it covers most everything you need, except the modern Basic Oxygenation Process (BOP) for making steel.

http://www.archive.org/details/makingshapingan00frangoog

You can also find used copies (or the most recent version) at Amazon and other book sellers from about $40 up to $200.
Thank you, Chris, that seems to be precisely the type of thing I was looking for. Hopefully it will elaborate on the medieval smith more than the equivalent texts I have previously read.
Again, thank you...

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