Fagor Iron History

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The gift that camedown from the heavensA brief history of workingiron and other metals

e don'tknow how Homo Sapiens f irst came in contactwith metals. They probablystumbled across them in anatural state, by pure chance.Gold nuggets gleamed in therivers, green coloured mala

chite nodules beckoned; meteoritesfell from the sky wrth hard polishedshapes that made them seem like giftsfrom the gods. In fact, the latter seemsto be highly plausible. Much has beendocumented regarding the manufacture of iron tools by Eskimos inGreen-land. They used materials that camefrom a huge 30 ton meteori te that fell

In this issue ofthe Company Journal weare commemorating the 50th Anniver-sary of Fagor Arrasate. A short walk inthe park compared to the long march ofhumanity since the first uses of metalwere revealed.

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Manual forge: The forge of Vul-can from the master Velasquez.Prado Museum, Madrid.

to that snowy spot in long-ago times.Today, that same meteorite is found inthe Museum of Natural History in NewYork. We believe that gold and copper,often found in nature in theirfree state,were the first metals known to humanbeings. Particularly gold, which in earlier times, was much more abundantthan today.OUT ancestors must have noticed thatthese colourful stones didn't behave likethe rest of the rocks that they used to


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. . . . . u ~ s n.' __u_ _ __ - ~ _ J . 1 _ ~ __ ~ u . _ ~ . . . _ ..'_ J i \ ; . " __n.'_.'make tools. They were shiny and colourful; they didn' t break when they werestruck but changed shape and werestretched; gold wasn't effected by theweather, rain or abrasion; when it wasrubbed with another material it becameshiny (and already, even then, humanbeings possessed the aesthetic sensethat is ours alone, as well 35 the greedthat drove them to fight for possessionof these sparkling stones); it soundednice when it was dropped, and above all,it was harder than the rocks known upuntil that time. This was highlyhelpful forsurvival. If they mastered their surroundings using flint tools, then metal gavethem an overwhelming advantage.Atsomepoint, abitof coppermusthavefallen in the fire. First it changed its co-lour, then got soft, ;and finally it melted.When the liquid cooled, it formed cop-per plate with the shape that it had taken just before solidifying. Primitive humans realized that those stones couldbe liquified and re-solidified in a shapethat was useful to them. They alsolearnedthat byheating themetalit couldbe fairly easily modelled just by str iking it. They converted this mysteriousrock into brilliant objects and made allform of different shapes; principally,weapons. But also everyday tools andfinally, decorations and ritual objects.Copper was the f irst metal masteredby man. According to archaeologists,these events ought to havetaken placesometime between the years 6000and12000 before Christ. On the first date,the use of copper seems to have beencommon. But in 1960 an ornamentalcopper pendant found near the Za-gras Mountains (today between lrakand Iran), bevelled and pierced, seemsto date back to 10,000 B.C, meaningthat metals were already being skilfullyworked at that time. In the beginning ofthe period they probably just shapedsmall cold pieces of pure metal foundon the ground, and at the end theywere using fire intentionally.Oncehumansobservedthat theycould"derive copper (which at that t ime hadprobably been graced with a sacredname) from a rock, i t wasn' t long be-fore they were looking for other rockswith which they could do somethingsimilar. The next thing they discoveredwas tin. And they found that by mixingthe two in a particularproportion (90%Cu + 10% Sn), the resulting metal wasstill harder. More difficult to work. yes,but harder and better for manufacturing swords and arrows, and so beginsthe Bronze Age.

Malachite from which cop-per is extracted. I ts greencolour, so different fromother rocks, made it thefirst metal used by primitiveman.

some places on the planet, wherebronze was never used, that moveddirectly from the Neolithic Age to theIron Age, such as sub-Saharan Africa.The discovery of copper was jealouslyguarded by the communities that hadit. It gavethem an important advantagein war. The secret was so importantthat it d idn' t get to Iran or Afghanistanuntil 2000 years later and didn't makeit to China until 1600 B.C., during theShang dynasty.From Sumerian writings that survivetoday we can glean that around theyear 3000 B.C, three metals (gold, silver, andcopper) and one alloy (bronze)were being worked. These same writings mention there was already a differentiation of occupations; on the onehand, those which obtain the metal ,and on the other, those which formtools or ceremonial objects. They maybe called blacksmiths, goldsmiths andsilversmiths.However, in order to melt copper theyneeded significant quantities of wood.Some 100Kg for each 5Kg of copper.

It could be argued that ecological de-terioration began with the need to cutdown lots of trees in order to makecharcoal wi th wh ich to fuel fires hotenough to melt copper or bronze. But,then, the Earth was covered with lushforests and this caused no problem.Between the years 2300 B.C. and1800 B.C, minerals and techniquesthat would change the world werediscovered. Humans were now acquainted with the existence of ironf rom meteorites. It was believed tobe a gif t from the heavens. Of coursethey did not know that they were dealing with iron, but theyworshiped theserocks sent from on high by the gods.In Samaria, iron was called "heaven'srocks" or "heaven's fire" and in Egypt"celestial black copper". In fact, it isbelieved that it was far more highlyvalued and expensive than gold. TheEgyptians were the first to tr y t o tamemeteorites but the temperatures thatthey could produce with their firesdidn' t get good results. They couldonly make small objects destined forthe upper echelons. That 's why themummy of the pharaoh Tutankhamenhad a small dagger of meteoric ironhanging from its neck. Egyptian blacksmiths tried to increase the temperature by blowing air into the fire, as canbe seen in some bas-reliefs, but theyonly reached 1200DC, a long way fromthe required 1600DC.Later, in t he Middle East and on thebanks of the Indian Ocean, mineralswere found which provided somethingsimilar to what was obtained frommeteorites. First, they probably cameacross pyrite which might have beenconfused with gold, and later, haematite or biotite.Some 500; j"earsJater. in Anatolia andli d pe


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Egyptian bas-relief where we can see two artisans blowing in a crucible where meteoric iron is being reduced.

Once semi-purified iron was obtained(not of today's quality but containingmany impuri ties) it was sent to theforging process. The iron mass wasre-smelted in a simple hole to obtainpig iron. It was reheated and hammered into sheetsor wire so that toolsand weapons could be made. Thepounding not only gave shape to ironbut also expelled the impurities.

shields, copper and tin were becoming scarce throughout the Mediterranean basin. Between the years 1000and 600 B.C. iron was widely usedthroughout Europe and Asia. On thehorn of Africa, seemingly independently, it also began to be used on alarge scale. On the other hand, ironindustry never developed in Americaand it was the Spanish colonists whotook it to the new continent.

Without knowledge of the physicochemical concepts that govem ironmetallurgy, tool-making was an art. A

It was the Greeks and the Chinesewho created an improved processwhich would last thi rty centuries byheating layers of metal and charcoalto obtain rudimentary wrought iron.The mineral and the charcoal werestacked in layers in order to get thebest heat distribution throughout themass that was being smelted. Altermany hours of heating, a mass of hotmineral was obtained that was perfectfor beating with hammers and knocking off the impurities in sheets, leavingcrude iron.

The process of tempering and rapidcooling by submerging the piece inliquidwasdeveloped.With thismethod,the hot metal , which was primarily inthe form of austenite, maintains itscrystallographic structureand ductility.If i t is cooled slowly, the structure willchange to pearlite (ferr ite wi th morecementite)and have inferiormechanicalproperties. Often, this cooling can betoo fast changing the metaJlographicstructure to martensite, very hard butfragile. Without understanding thesephysical concepts, the artisans figuredoutthat by slightly reheating the sword(annealing) for a precise amount oft ime, it would acquire more ducti li ty.Butif overheated, it would become tooducti le and bend when struck by theenemy's axe!

The chemical reaction produced in thefurnace is:

weapons were stronger they could belonger without fearing that they breakin a fight. And having more distancefrom the enemy combatant was havinglife insurance. And the new materialwasn't essential only for war, but forknives, ploughs, spades....a whole series of implements making life better.The Hittite technology spread rapidlyaround the world. It was a question ofsurvival. Notonly did theiron weaponscut the bronze ones and dest roy the

The iron meteorite of Greenland. Named IlAhnighito''t it is exhibited inthe American Natural History museum in New York city. It is the larges t of the three meteori tes recovered by Robert Peary at t he end of1890. It Is one 34 tonne piece of i ron and nickel and measures 330cmlong, 210cm high, and 165cm t hick . Esk imos made knives and harpoons from it fo r many generations.

ceed at liquifying the iron, they didmanage to produce the temperaturerequired to cause the chemical reaction of reduction, separating the ironfrom the gangue. There is no liquidiron yet but there is solid iron thatcan be forged th rough mechanicalforce. The Hittite were the first peopleto work iron on a large scale. Theyfounded an enormous empire basedon swords and weapons of this metal,which in battle, easily sliced throughthe enemy's bronze. In addition, as the

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Primitive furnaces where iron reduction was dooe.

Hittite bas-relief where a deity with an iron lance fights against thegod of evil, Yanka, represented by a snake.

In the 17'h century, charcoal began tobe substituted by coal, but the ironobtained was very, very fragile. Todaywe know that this fragi li ty was due tosulphur impuri ties produced by themethod. The solution was provided,surprisingly, by beer brewers. They hadbeen using carbon to toast barley butthe quality and smell of the beer wasbad. So, theyinvented coke (coal heatedin an oven without oxygen, causingevaporation of all its impurities). Withcoke, there was . q ~ a l i t y iron again.

In the middle Ages, when the first hydraulic devices allowed automation ofhammering. production and productivity improved. The process continued being the same, but required lesshuman effort.

In the 12 lh century, the Occident gotnews of a new advance regarding Damascus steel, so called because thecrusades found that type steels in thiscity. Al though i t's possible tha t thetechnique was used from the 4th century before Chr is t (and i t was clear lydocumented in the 6th century A.D.)Christians had no knowledge of it until many centuries later. Legend has itthat during the Crusades, Richard theUonhearted met Saladin. The Crusade King wanted to demonstrate thepower of his sword and sliced througha huge rock with- one magnificentblow. Saladin, without batting an eyelid, threw a fine silk c lo th into the airand cleanly cut it into two pieceswhileit descended. Never had King Richardseen anything like it. A blade so sharpthat it could cut a flying bitof cloth andso hard as to be used in battle againstanothersword. What wasthe secret ofthis type of iron?The process started with a ferric massrich in carbon called wootz and madein India. It was obtained by mixing aniron mineral with wood, both sheetsand charcoal, in a rock fumace at atemperature of 1200C. The wootzeswere tranported to Persia by caravan.It was heated at 1200C and slowlycooled tak ing several hours. Then itwas heated again - and this was thesecret - at 750C. It was then forgedwith wheels to break down the martensitethat hadformed, also creating asurface with a beautiful bluish design.In Russia, independently, the processwas also known and called bulat.

to 6 meters, were introduced (theprecursors of today's blast furnaces).They could liquefy iron and producedthe first tapping of smelted iron whichlaterwasused tomanufactureall kindsof object in moulds.

The basic procedurewas not modifieduntil the end of the Middle Ageswhen taller furnaces, measuring 4

"Iron mines gave man both the mostexcellentand most perverse arm. Withit we cleave the Earth, plant forests.work our fields and gardens, and bypruning the wild grape vines we makethem flourish each year. With this armwe build homes and demolish rocks.Butwith this sameiron wemake war, wefight and we pillage; we don'tjustuseitclose up but launch it far, sometimeswith catapults, sometimes with strongarms and sometimes in the form ofsharpened arrows. /n my opinion, thisis the most depraved artifice of humaningenuity. $0 that death arrives soonerfor a man, we make i t fly, creatingarrows and lances. Hence, fault mustbe assigned to man, not to nature."

In the first century of ourage. Pliny theelder wrote:

When the Roman Empirerises over theOccident, iron is already the standardmetal. It is no longer a gift f rom theheavens but has become a commonmaterial in everyday life. And war.

li tt le too much heat, too much or notenough hammering. inadequate tempering. or too muoh annealing wouldspoil the sword. This process was critical. The heating time, hammering, etc.had to becarefully controlled or it couldresult in very softor veryfragile swords.At times, by chance, the artisans wouldget the times and the forging just r ightand produce, without knowing it, realsteel. at least on the surface area.Some swords made that way have become legendary; because although noone understood it. they were not madeof wroughtiron but near steel. Such areEl Cid'sTlZona, the coronation sword ofCharlemagne, and the not real, legendary Excalibur, weapon of King Arthur.

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T h e b l ad e o f a ste el Da m ascu s sword and it s arabesque details.

Smelted iron, with i ts carbon content,was hard but fragile, w ith poor metallurgic quality. Besides, even thoughthe product ion had grown a lot s incethe f irst century, it was lud ic rous incomparison with today, meaning thatthe procedure was expensive.In 1740 Huntsman invented the cru-c ib le procedure where bars of ironpuddle were sme lted with charcoaland sand in a crucible . The smeltediron was poured to form 30 to 40 kg.ingots. I t was sti ll a h igh carbon content iron, hard but fragile.The European countries were continuous ly at war; with each other or theircolonies. Firearmswere no w common.Armies urgently needed solutions. Ironcannons and rif les di d n ot have thestrength to withstand the ever morepower fu l charges. They exploded,softened or lost their shape.At the end of the 18lh century, theoretical studies began to shed l ight on

the fac t tha t carbon con ten t as wellas control of other components l ikephosphorous and sulphur, were thekey to perfect steel. The works of theSwedish chemist Bergmann (who'sChemical Affinity inspired Goethe toexplain the aff inity of love) and theFrench Vandemonte are decisive inthis respect. But still, no one managesto obtain the correct carbon contentbecause as already seen, it must bevery low, below 0.5%. How can sucha small exac t quantity of carbon beadded to iron?Finally, during th e 19 1t1 century, in 1855,the Englishman Bessemer discovereda fast economical procedure for de-carbonising smelted iron and converting it to steel in economical quantities.The concept is based on removingcarbon from high carbon content ironby burning it of f instead of trying toadd t iny bits of carbon to pure iron.His invent ion consisted of passing astrong current of air through a pearshaped furnace where the sme lted

= ~ t -~ -~ iflT L, ,.

iron was found. The oxygen in the airreacted violently with the carbon pro-ducing a spectacular blaze, symbol ofthe industrial revolut ion, and carbonwas reduced to proport ions of lessthan 0.5% achieving steel s imilar tothat of today. Every tapping was of 20to 45 tons and only 30 minutes wereneeded to get it. Bessemer registeredhis patent in 1856 and the AmericanKelly patented the same process inKentucky in 1857. Nevertheless, onlyBessemer had the economic meansto develop and improve the invention.Curiously, the first Bessemer installat ion was constructed in Wyandotte(Michigan) in 1864.Inpractice, Bessemer found numerousproblems due to fundamentaldependence upon iron minerals whichmight result in high quali ty steel orfragile useless garbage. Persevering,he understood that fragility wascaused by sulphur and phosphorousimpurities in the mineral. Coating thefumace with l imestone, he managedto get i t to react with the phosphorousand diluted with slag, leaving the steelin the right condition. Other engineerswere constantly finding improvements.Manganese was added to eliminateany extra oxygen in the mix.The introduction of theMartin-Siemensreverberatory furnace in 1964 wasanotherstep forward. It accommodatedthe production of 200 tons of steel peroperation (although more slowly) andfinally, in 1890, the Heroult e lect ricfumace, which permitted higherqualitysteel and took economic advantage ofscrap, was introduced. With theMartinSiemens furnace, at the beginning ofthe 1900s,the world production of steelhad already risen to 30 million tonnes,a number that exploded to 90 milliontonnes when the First World War brokeout. Starting in 1955, the LD Converterbased on the oxygen lance constituteda significant development. It permittedlarger and higher quali ty productionof steel. Improved electric furnacessignified a tremendous progress at thistime.Once steel could be economically ob -tained in large quantities. systems forprocessing and forming, such as millsand cutting lines were developed.After the Second World War, the pro-duction of steel did not stop growinguntil reaching the current 1,300 milliontonnes.

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H am m er f or ge d ri ve n by a h ydr a ul i c wh ee l , p er ta in s t o t he M id dl eAges.

c 0 ~ i P ANi J 0 U A N A L

Besides the manufacture of steel,processes for obtaining pure iron wereimproved starting in the 181t1 century.


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Bessemer Converter.

Pure iron was obtained principallythrough the reduction of ironoxidewithhydrogen; later larger quantities wereachieved through electrodeposition ofa pure sulphate or chloride solution;and finally thousands of tons of pureiron were produced using differentialoxidation. With this method practicallyall impurities are eliminated by theoxidation affected in a in a liquid ironbath resulting in smetted iron.It's not strange that iron is such an im-portant material. We breathe thanks tothe fact it is found in our haemoglobin.Ourplanethashugequantitiesof it (5%of the crust of the Earth and a largepart of the nucleus (NiFe)). It appearsin all asteroids, on rocky planets, andit's created in the heart of all stars.Iron is the last thing unleashed whenstars explode as supernovas in thegreat cosmic spectacle that oncemore creates life, scattering cosmicmaterials in space, star dust fromwhich arises all that exists.We could return to the beginning andsay that iron is truly a gift from theheavens.

~ f - " - " - _ ! , f - J ' ' = ; . _ ~ - + _ . ~ ', .....

. ,, . ' ~ J ~1/" f '- '.

.I, ], l.~ Milling worksh.Qp according to the DideroJ; Encyclopaedia (1771).

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Fagor Iron History

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