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Thesteelcableofacollierywindingtower

SteelFromWikipedia,thefreeencyclopedia

Steelsarealloysofironandcarbon,widelyusedinconstructionandotherapplicationsbecauseoftheirhightensilestrengthsandlowcosts.Carbon,otherelements,andinclusionswithinironactashardeningagentsthatpreventthemovementofdislocationsthatotherwiseoccurinthecrystallatticesofironatoms.

Thecarbonintypicalsteelalloysmaycontributeupto2.1%ofitsweight.Varyingtheamountofalloyingelements,theirformationinthesteeleitherassoluteelements,orasprecipitatedphases,retardsthemovementofthosedislocationsthatmakeironsoductileandweak,andthuscontrolsqualitiessuchasthehardness,ductility,andtensilestrengthoftheresultingsteel.Steel'sstrengthcomparedtopureironisonlypossibleattheexpenseofductility,ofwhichironhasanexcess.

Althoughsteelhadbeenproducedinbloomeryfurnacesforthousandsofyears,steel'suseexpandedextensivelyaftermoreefficientproductionmethodsweredevisedinthe17thcenturyforblistersteelandthencruciblesteel.WiththeinventionoftheBessemerprocessinthemid19thcentury,aneweraofmassproducedsteelbegan.ThiswasfollowedbySiemensMartinprocessandthenGilchristThomasprocessthatrefinedthequalityofsteel.Withtheirintroductions,mildsteelreplacedwroughtiron.

Furtherrefinementsintheprocess,suchasbasicoxygensteelmaking(BOS),largelyreplacedearliermethodsbyfurtherloweringthecostofproductionandincreasingthequalityofthemetal.Today,steelisoneofthemostcommonmaterialsintheworld,withmorethan1.3billiontonsbeingproducedannually.Itisamajorcomponentinbuildings,infrastructure,tools,ships,automobiles,machines,appliances,andweapons.Modernsteelisgenerallyidentifiedbyvariousgradesdefinedbyassortedstandardsorganizations.

Contents

1Definitionsandrelatedmaterials2Materialproperties

2.1Heattreatment3Steelproduction4Historyofsteelmaking

4.1Ancientsteel4.2WootzsteelandDamascussteel4.3Modernsteelmaking

4.3.1Processesstartingfrombariron4.3.2Processesstartingfrompigiron

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4.3.2Processesstartingfrompigiron5Steelindustry6Recycling7Contemporarysteel

7.1Carbonsteels7.2Alloysteels7.3Standards

8Uses8.1Historical8.2Longsteel8.3Flatcarbonsteel8.4Stainlesssteel8.5Lowbackgroundsteel

9Seealso10References

10.1Bibliography11Furtherreading12Externallinks

Definitionsandrelatedmaterials

Thecarboncontentofsteelisbetween0.002%and2.1%byweightforplainironcarbonalloys.Thesevaluesvarydependingonalloyingelementssuchasmanganese,chromium,nickel,iron,tungsten,carbonandsoon.Basically,steelisanironcarbonalloythatdoesnotundergoeutecticreaction.Incontrast,castirondoesundergoeutecticreaction.Toolittlecarboncontentleaves(pure)ironquitesoft,ductile,andweak.Carboncontentshigherthanthoseofsteelmakeanalloycommonlycalledpigironthatisbrittleandnotmalleable.Alloysteelissteeltowhichalloyingelementshavebeenintentionallyaddedtomodifythecharacteristicsofsteel.Commonalloyingelementsinclude:manganese,nickel,chromium,molybdenum,boron,titanium,vanadium,andniobium.[1]Additionalelementsmaybepresentinsteel:manganese,phosphorus,sulfur,silicon,andtracesofoxygen,nitrogen,andcopper.

Alloyswithahigherthan2.1%carboncontent,dependingonotherelementcontentandpossiblyonprocessing,areknownascastiron.Castironisnotmalleableevenwhenhot,butitcanbeformedbycastingasithasalowermeltingpointthansteelandgoodcastabilityproperties.[1]Steelisalsodistinguishablefromwroughtiron(nowlargelyobsolete),whichmaycontainasmallamountofcarbonbutlargeamountsofslag.Notethatthepercentagesofcarbonandotherelementsquotedareonaweightbasis.

Materialproperties

IroniscommonlyfoundintheEarth'scrustintheformofanore,usuallyanironoxide,suchasmagnetite,hematiteetc.Ironisextractedfromironorebyremovingtheoxygenthroughcombinationwithapreferredchemicalpartnersuchascarbonthatislosttotheatmosphereascarbondioxide.Thisprocess,knownassmelting,wasfirstappliedtometalswithlowermeltingpoints,suchastin,whichmeltsatapproximately250C(482F)andcopper,whichmeltsatapproximately1,100C(2,010F).Incomparison,castironmeltsatapproximately1,375C(2,507F).[2]Smallquantitiesofironweresmeltedinancienttimes,inthe

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Ironcarbonphasediagram,showingtheconditionsnecessarytoformdifferentphases

solidstate,byheatingtheoreburiedinacharcoalfireandweldingthemetaltogetherwithahammer,squeezingouttheimpurities.Withcare,thecarboncontentcouldbecontrolledbymovingitaroundinthefire.

AllofthesetemperaturescouldbereachedwithancientmethodsthathavebeenusedsincetheBronzeAge.Sincetheoxidationrateofironincreasesrapidlybeyond800C(1,470F),itisimportantthatsmeltingtakeplaceinalowoxygenenvironment.Unlikecopperandtin,liquidorsolidirondissolvescarbonquitereadily.Smeltingresultsinanalloy(pigiron)thatcontainstoomuchcarbontobecalledsteel.[2]Theexcesscarbonandotherimpuritiesareremovedinasubsequentstep.

Othermaterialsareoftenaddedtotheiron/carbonmixturetoproducesteelwithdesiredproperties.Nickelandmanganeseinsteeladdtoitstensilestrengthandmaketheausteniteformoftheironcarbonsolutionmorestable,chromiumincreaseshardnessandmeltingtemperature,andvanadiumalsoincreaseshardnesswhilemakingitlesspronetometalfatigue.[3]

Toinhibitcorrosion,atleast11%chromiumisaddedtosteelsothatahardoxideformsonthemetalsurfacethisisknownasstainlesssteel.Tungsteninterfereswiththeformationofcementite,allowingmartensitetopreferentiallyformatslowerquenchrates,resultinginhighspeedsteel.Ontheotherhand,sulfur,nitrogen,andphosphorusmakesteelmorebrittle,sothesecommonlyfoundelementsmustberemovedfromthesteelmeltduringprocessing.[3]

Thedensityofsteelvariesbasedonthealloyingconstituentsbutusuallyrangesbetween7,750and8,050kg/dm3(484,000and503,000lb/cuft),or7.75and8.05g/cm3(4.48and4.65oz/cuin).[4]

Eveninanarrowrangeofconcentrationsofmixturesofcarbonandironthatmakeasteel,anumberofdifferentmetallurgicalstructures,withverydifferentpropertiescanform.Understandingsuchpropertiesisessentialtomakingqualitysteel.Atroomtemperature,themoststableformofpureironisthebodycenteredcubic(BCC)structurecalledferriteoriron.Itisafairlysoftmetalthatcandissolveonlyasmallconcentrationofcarbon,nomorethan0.005%at0C(32F)and0.021wt%at723C(1,333F).At910Cpureirontransformsintoafacecenteredcubic(FCC)structure,calledausteniteoriron.TheFCCstructureofaustenitecandissolveconsiderablymorecarbon,asmuchas2.1%[5](38timesthatofferrite)carbonat1,148C(2,098F),whichreflectstheuppercarboncontentofsteel,beyondwhichiscastiron.[6]

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Whensteelswithlessthan0.8%carbon(knownasahypoeutectoidsteel),arecooled,theausteniticphase(FCC)ofthemixtureattemptstoreverttotheferritephase(BCC).ThecarbonnolongerfitswithintheFCCstructure,resultinginanexcessofcarbon.Onewayforcarbontoleavetheausteniteisforittoprecipitateoutofsolutionascementite,leavingbehindasurroundingphaseofBCCironthatislowenoughincarbontotaketheformofferrite,resultinginaferritematrixwithcementiteinclusions.CementiteisahardandbrittleintermetalliccompoundwiththechemicalformulaofFe3C.Attheeutectoid,0.8%carbon,thecooledstructuretakestheformofpearlite,namedforitsresemblancetomotherofpearl.Onalargerscale,itappearsasalamellarstructureofferriteandcementite.Forsteelsthathavemorethan0.8%carbon,thecooledstructuretakestheformofpearliteandcementite.[7]

Perhapsthemostimportantpolymorphicformofsteelismartensite,ametastablephasethatissignificantlystrongerthanothersteelphases.Whenthesteelisinanausteniticphaseandthenquenchedrapidly,itformsintomartensite,astheatoms"freeze"inplacewhenthecellstructurechangesfromFCCtoadistortedformofBCCastheatomsdonothavetimeenoughtomigrateandformthecementitecompound.Dependingonthecarboncontent,themartensiticphasetakesdifferentforms.Belowapproximately0.2%carbon,ittakesanferriteBCCcrystalform,butathighercarboncontentittakesabodycenteredtetragonal(BCT)structure.Thereisnothermalactivationenergyforthetransformationfromaustenitetomartensite.Moreover,thereisnocompositionalchangesotheatomsgenerallyretaintheirsameneighbors.[8]

Martensitehasalowerdensitythandoesaustenite,sothatthetransformationbetweenthemresultsinachangeofvolume.Inthiscase,expansionoccurs.Internalstressesfromthisexpansiongenerallytaketheformofcompressiononthecrystalsofmartensiteandtensionontheremainingferrite,withafairamountofshearonbothconstituents.Ifquenchingisdoneimproperly,theinternalstressescancauseaparttoshatterasitcools.Attheveryleast,theycauseinternalworkhardeningandothermicroscopicimperfections.Itiscommonforquenchcrackstoformwhensteeliswaterquenched,althoughtheymaynotalwaysbevisible.[9]

Heattreatment

Therearemanytypesofheattreatingprocessesavailabletosteel.Themostcommonareannealing,quenching,andtempering.Annealingistheprocessofheatingthesteeltoasufficientlyhightemperaturetosoftenit.Thisprocessgoesthroughthreephases:recovery,recrystallization,andgraingrowth.Thetemperaturerequiredtoannealsteeldependsonthetypeofannealingtobeachievedandtheconstituentsofthealloy.[10]

Quenchingandtemperingfirstinvolvesheatingthesteeltotheaustenitephasethenquenchingitinwateroroil.Thisrapidcoolingresultsinahardbutbrittlemartensiticstructure.[8]Thesteelisthentempered,whichisjustaspecializedtypeofannealing,toreducebrittleness.Inthisapplicationtheannealing(tempering)processtransformssomeofthemartensiteintocementite,orspheroiditeandhencereducestheinternalstressesanddefects.Theresultisamoreductileandfractureresistantsteel.[11]

Steelproduction

Whenironissmeltedfromitsore,itcontainsmorecarbonthanisdesirable.Tobecomesteel,itmustbereprocessedtoreducethecarbontothecorrectamount,atwhichpointotherelementscanbeadded.Inmodernfacilities,thisliquidisthencontinuouslycastintolongslabsorcastintoingots.Approximately

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Ironorepelletsfortheproductionofsteel

BloomerysmeltingduringtheMiddleAges

96%ofsteeliscontinuouslycast,whileonly4%isproducedasingots.[12]

Theingotsarethenheatedinasoakingpitandhotrolledintoslabs,blooms,orbillets.Slabsarehotorcoldrolledintosheetmetalorplates.Billetsarehotorcoldrolledintobars,rods,andwire.Bloomsarehotorcoldrolledintostructuralsteel,suchasIbeamsandrails.Inmodernsteelmillstheseprocessesoftenoccurinoneassemblyline,withorecominginandfinishedsteelcomingout.[13]Sometimesafterasteel'sfinalrollingitisheattreatedforstrength,howeverthisisrelativelyrare.[14]

Historyofsteelmaking

Ancientsteel

Steelwasknowninantiquity,andmayhavebeenproducedbymanagingbloomeriesandcrucibles,orironsmeltingfacilities,inwhichtheycontainedcarbon.[15][16][17]

TheearliestknownproductionofsteelarepiecesofironwareexcavatedfromanarchaeologicalsiteinAnatolia(KamanKalehoyuk)andarenearly4,000yearsold,datingfrom1800BC.[18][19]HoraceidentifiessteelweaponslikethefalcataintheIberianPeninsula,whileNoricsteelwasusedbytheRomanmilitary.[20]

SouthIndianandMediterraneansourcesincludingAlexandertheGreat(3rdc.BC)recountthepresentationandexporttotheGreeksof100talentsofSouthIndiansteel.ThereputationofSericironofSouthIndia(wootzsteel)amongsttheGreeks,Romans,Egyptians,EastAfricans,ChineseandtheMiddleEastgrewconsiderably,ahighqualityhighcarbonironandsteelimportedfromTamilpeopleofthedynastyChera.[17]MetalproductionsitesinSriLankautilizedthesenoveltechniquesusinguniquewindfurnacesdrivenbythemonsoonwinds,capableofproducinghighcarbonsteel,aswellasimportedartefactsofancientironandsteelfromKodumanal.LargescaleWootzsteelproductioninTamilakamusingcruciblestheyinventedandcarbonsourcessuchastheplantAvramoccurredbythesixthcenturyBC,thepioneeringprecursortomodernsteelproductionandmetallurgy.[16][17]

SteelwasproducedinlargequantitiesinSpartaaround650BC.[21][22]

TheChineseoftheWarringStatesperiod(403221BC)hadquenchhardenedsteel,[23]whileChineseoftheHandynasty(202BC220AD)createdsteelbymeltingtogetherwroughtironwithcastiron,gaininganultimateproductofacarbonintermediatesteelbythe1stcenturyAD.[24][25]TheHayapeopleofEast

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Africainventedatypeoffurnacetheyusedtomakecarbonsteelat1,802C(3,276F)nearly2,000yearsago.EastAfricansteelhasbeensuggestedbyRichardHookertodatebackto1400BC.[26][27]

WootzsteelandDamascussteel

EvidenceoftheearliestproductionofhighcarbonsteelintheIndianSubcontinentarefoundinKodumanalinTamilNaduarea,GolcondainAndhraPradeshareaandKarnataka,andinSamanalawewaareasofSriLanka.[28]ThiscametobeknownasWootzsteel,producedinSouthIndiabyaboutsixthcenturyBCandexportedglobally.[29][30]Thesteeltechnologyexistedpriorto326BCintheregionastheyarementionedinliteratureofSangamTamil,ArabicandLatinasthefineststeelintheworldexportedtotheRomans,Egyptian,ChineseandArabsworldsatthattimewhattheycalledSericIron.[31]A200BCTamiltradeguildinTissamaharama,intheSouthEastofSriLanka,broughtwiththemsomeoftheoldestironandsteelartefactsandproductionprocessestotheislandfromtheclassicalperiod.[32][33][34][35]TheChineseandlocalsinAnuradhapura,SriLankahadalsoadoptedtheproductionmethodsofcreatingWootzsteelfromtheCheraDynastyTamilsofSouthIndiabythe5thcenturyAD.[36][37]InSriLanka,thisearlysteelmakingmethodemployedauniquewindfurnace,drivenbythemonsoonwinds,capableofproducinghighcarbonsteel.[38][39]SincethetechnologywasacquiredfromtheTamiliansfromSouthIndia,theoriginofsteeltechnologyinIndiacanbeconservativelyestimatedat400500BC.[29][39]

Wootz,alsoknownasDamascussteel,isfamousforitsdurabilityandabilitytoholdanedge.Itwasoriginallycreatedfromanumberofdifferentmaterialsincludingvarioustraceelements,apparentlyultimatelyfromthewritingsofZosimosofPanopolis.However,thesteelwasanoldtechnologyinIndiawhenKingPoruspresentedasteelswordtotheEmperorAlexanderin326BC.Itwasessentiallyacomplicatedalloywithironasitsmaincomponent.Recentstudieshavesuggestedthatcarbonnanotubeswereincludedinitsstructure,whichmightexplainsomeofitslegendaryqualities,thoughgiventhetechnologyofthattime,suchqualitieswereproducedbychanceratherthanbydesign.[40]Naturalwindwasusedwherethesoilcontainingironwasheatedbytheuseofwood.TheancientSinhalesemanagedtoextractatonofsteelforevery2tonsofsoil,[38]aremarkablefeatatthetime.OnesuchfurnacewasfoundinSamanalawewaandarchaeologistswereabletoproducesteelastheancientsdid.[38][41]

Cruciblesteel,formedbyslowlyheatingandcoolingpureironandcarbon(typicallyintheformofcharcoal)inacrucible,wasproducedinMervbythe9thto10thcenturyAD.[30]Inthe11thcentury,thereisevidenceoftheproductionofsteelinSongChinausingtwotechniques:a"berganesque"methodthatproducedinferior,inhomogeneous,steel,andaprecursortothemodernBessemerprocessthatusedpartialdecarbonizationviarepeatedforgingunderacoldblast.[42]

Modernsteelmaking

Sincethe17thcenturythefirststepinEuropeansteelproductionhasbeenthesmeltingofironoreintopigironinablastfurnace.[43]Originallyemployingcharcoal,modernmethodsusecoke,whichhasprovenmoreeconomical.[44][45][46]

Processesstartingfrombariron

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ABessemerconverterinSheffield,England

ASiemensMartinsteelovenfromtheBrandenburgMuseumofIndustry.

Intheseprocessespigironwas"fined"inafineryforgetoproducebariron,whichwasthenusedinsteelmaking.[43]

TheproductionofsteelbythecementationprocesswasdescribedinatreatisepublishedinPraguein1574andwasinuseinNurembergfrom1601.AsimilarprocessforcasehardeningarmourandfileswasdescribedinabookpublishedinNaplesin1589.TheprocesswasintroducedtoEnglandinabout1614andusedtoproducesuchsteelbySirBasilBrookeatCoalbrookdaleduringthe1610s.[47]

Therawmaterialforthisprocesswerebarsofiron.Duringthe17thcenturyitwasrealizedthatthebeststeelcamefromoregroundsironofaregionnorthofStockholm,Sweden.Thiswasstilltheusualrawmaterialsourceinthe19thcentury,almostaslongastheprocesswasused.[48][49]

Cruciblesteelissteelthathasbeenmeltedinacrucibleratherthanhavingbeenforged,withtheresultthatitismorehomogeneous.Mostpreviousfurnacescouldnotreachhighenoughtemperaturestomeltthesteel.TheearlymoderncruciblesteelindustryresultedfromtheinventionofBenjaminHuntsmaninthe1740s.Blistersteel(madeasabove)wasmeltedinacrucibleorinafurnace,andcast(usually)intoingots.[49][50]

Processesstartingfrompigiron

ThemodernerainsteelmakingbeganwiththeintroductionofHenryBessemer'sBessemerprocessin1855,therawmaterialforwhichwaspigiron.[51]Hismethodlethimproducesteelinlargequantitiescheaply,thusmildsteelcametobeusedformostpurposesforwhichwroughtironwasformerlyused.[52]TheGilchristThomasprocess(orbasicBessemerprocess)wasanimprovementtotheBessemerprocess,madebyliningtheconverterwithabasicmaterialtoremovephosphorus.

Another19thcenturysteelmakingprocesswastheSiemensMartinprocess,whichcomplementedtheBessemerprocess.[49]Itconsistedofcomeltingbariron(orsteelscrap)withpigiron.

ThesemethodsofsteelproductionwererenderedobsoletebytheLinzDonawitzprocessofbasicoxygensteelmaking(BOS),developedinthe1950s,andotheroxygensteelmakingmethods.Basicoxygensteelmakingissuperiortoprevioussteelmakingmethodsbecausetheoxygenpumpedintothefurnacelimitsimpuritiesthatpreviouslyhadenteredfromtheairused.[53]Today,electricarcfurnaces(EAF)areacommonmethodofreprocessingscrapmetaltocreatenewsteel.Theycanalsobeusedforconvertingpigirontosteel,buttheyusealotofelectricalenergy(about440kWhpermetricton),andarethusgenerallyonlyeconomicalwhenthereisaplentifulsupplyofcheapelectricity.[54]

Steelindustry

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Whitehotsteelpouringoutofanelectricarcfurnace.

Steelproductionbycountryin2007

Itiscommontodaytotalkabout"theironandsteelindustry"asifitwereasingleentity,buthistoricallytheywereseparateproducts.Thesteelindustryisoftenconsideredanindicatorofeconomicprogress,becauseofthecriticalroleplayedbysteelininfrastructuralandoveralleconomicdevelopment.[55]

In1980,thereweremorethan500,000U.S.steelworkers.By2000,thenumberofsteelworkersfellto224,000.[56]

TheeconomicboominChinaandIndiahascausedamassiveincreaseinthedemandforsteelinrecentyears.Between2000and2005,worldsteeldemandincreasedby6%.Since2000,severalIndian[57]andChinesesteelfirmshaverisentoprominencelikeTataSteel(whichboughtCorusGroupin2007),ShanghaiBaosteelGroupCorporationandShagangGroup.ArcelorMittalishowevertheworld'slargeststeelproducer.

In2005,theBritishGeologicalSurveystatedChinawasthetopsteelproducerwithaboutonethirdoftheworldshareJapan,Russia,andtheUSfollowedrespectively.[58]

In2008,steelbegantradingasacommodityontheLondonMetalExchange.Attheendof2008,thesteelindustryfacedasharpdownturnthatledtomanycutbacks.[59]

Theworldsteelindustrypeakedin2007.Thatyear,ThyssenKruppspent$12billiontobuildthetwomostmodernmillsintheworld,inCalvert,AlabamaandSepetiba,RiodeJaneiro,Brazil.TheworldwideGreatRecessionstartingin2008,however,sharplylowereddemandandnewconstruction,andsopricesfell.ThyssenKrupplost$11billiononitstwonewplants,whichsoldsteelbelowthecostofproduction.Finallyin2013,ThyssenKruppofferedtheplantsforsaleatunder$4billion.[60]

Recycling

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AsteelplantintheUnitedKingdom.

BethlehemSteelinBethlehem,Pennsylvaniawasoneoftheworld'slargestmanufacturersofsteelbeforeits2003closureandlaterconversionintoacasino.

Steelisoneoftheworld'smostrecycledmaterials,witharecyclingrateofover60%globally[61]intheUnitedStatesalone,over82,000,000metrictons(81,000,000longtons)wasrecycledintheyear2008,foranoverallrecyclingrateof83%.[62]

Contemporarysteel

Carbonsteels

Modernsteelsaremadewithvaryingcombinationsofalloymetalstofulfillmanypurposes.[3]Carbonsteel,composedsimplyofironandcarbon,accountsfor90%ofsteelproduction.[1]Lowalloysteelisalloyedwithotherelements,usuallymolybdenum,manganese,chromium,ornickel,inamountsofupto10%byweighttoimprovethehardenabilityofthicksections.[1]Highstrengthlowalloysteelhassmalladditions(usually

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Arollofsteelwool

Somemoremodernsteelsincludetoolsteels,whicharealloyedwithlargeamountsoftungstenandcobaltorotherelementstomaximizesolutionhardening.Thisalsoallowstheuseofprecipitationhardeningandimprovesthealloy'stemperatureresistance.[1]Toolsteelisgenerallyusedinaxes,drills,andotherdevicesthatneedasharp,longlastingcuttingedge.OtherspecialpurposealloysincludeweatheringsteelssuchasCorten,whichweatherbyacquiringastable,rustedsurface,andsocanbeusedunpainted.[69]Maragingsteelisalloyedwithnickelandotherelements,butunlikemoststeelcontainslittlecarbon0.01%).Thiscreatesaverystrongbutstillmalleablesteel.[70]

Eglinsteelusesacombinationofoveradozendifferentelementsinvaryingamountstocreatearelativelylowcoststeelforuseinbunkerbusterweapons.Hadfieldsteel(afterSirRobertHadfield)ormanganesesteelcontains1214%manganesewhichwhenabradedstrainhardenstoformanincrediblyhardskinwhichresistswearing.Examplesincludetanktracks,bulldozerbladeedgesandcuttingbladesonthejawsoflife.[71]

In2015abreakthroughincreatingastronglightaluminiumsteelalloywhichmightbesuitableinapplicationssuchasaircraftwasannouncedbyresearchersatPohangUniversityofScienceandTechnology.AddingsmallamountsofnickelwasfoundtoresultinprecipitationasnanoparticlesofbrittleB2intermetalliccompoundswhichhadpreviouslyresultedinweakness.TheresultwasacheapstronglightsteelalloywhichisslatedfortrialproductionatindustrialscalebyPOSCO,aKoreansteelmaker.[72][73]

Standards

Mostofthemorecommonlyusedsteelalloysarecategorizedintovariousgradesbystandardsorganizations.Forexample,theSocietyofAutomotiveEngineershasaseriesofgradesdefiningmanytypesofsteel.[74]TheAmericanSocietyforTestingandMaterialshasaseparatesetofstandards,whichdefinealloyssuchasA36steel,themostcommonlyusedstructuralsteelintheUnitedStates.[75]

Uses

Ironandsteelareusedwidelyintheconstructionofroads,railways,otherinfrastructure,appliances,andbuildings.Mostlargemodernstructures,suchasstadiumsandskyscrapers,bridges,andairports,aresupportedbyasteelskeleton.Eventhosewithaconcretestructureemploysteelforreinforcing.Inaddition,itseeswidespreaduseinmajorappliancesandcars.Despitegrowthinusageofaluminium,itisstillthemainmaterialforcarbodies.Steelisusedinavarietyofotherconstructionmaterials,suchasbolts,nails,andscrewsandotherhouseholdproductsandcookingutensils.[76]

Othercommonapplicationsincludeshipbuilding,pipelines,mining,offshoreconstruction,aerospace,whitegoods(e.g.washingmachines),heavyequipmentsuchasbulldozers,officefurniture,steelwool,tools,andarmourintheformofpersonalvestsorvehiclearmour(betterknownasrolledhomogeneousarmourinthisrole).

Historical

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Acarbonsteelknife

Asteelbridge

Asteelpylonsuspendingoverheadpowerlines

BeforetheintroductionoftheBessemerprocessandothermodernproductiontechniques,steelwasexpensiveandwasonlyusedwherenocheaperalternativeexisted,particularlyforthecuttingedgeofknives,razors,swords,andotheritemswhereahard,sharpedgewasneeded.Itwasalsousedforsprings,includingthoseusedinclocksandwatches.[49]

Withtheadventofspeedierandthriftierproductionmethods,steelhasbecomeeasiertoobtainandmuchcheaper.Ithasreplacedwroughtironforamultitudeofpurposes.However,theavailabilityofplasticsinthelatterpartofthe20thcenturyallowedthesematerialstoreplacesteelinsomeapplicationsduetotheirlowerfabricationcostandweight.[77]Carbonfiberisreplacingsteelinsomecostinsensitiveapplicationssuchasaircraft,sportsequipmentandhighendautomobiles.

Longsteel

AsreinforcingbarsandmeshinreinforcedconcreteRailroadtracksStructuralsteelinmodernbuildingsandbridgesWiresInputtoreforgingapplications

Flatcarbonsteel

MajorappliancesMagneticcoresTheinsideandoutsidebodyofautomobiles,trains,andships.

Stainlesssteel

CutleryRulersSurgicalinstrumentsWatchesGunsRailpassengervehicles

Lowbackgroundsteel

SteelmanufacturedafterWorldWarIIbecamecontaminatedwithradionuclidesduetonuclearweaponstesting.Lowbackgroundsteel,steelmanufacturedpriorto1945,isusedforcertainradiationsensitiveapplicationssuchasGeigercountersandradiationshielding.

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Astainlesssteelgravyboat

Seealso

CarbonsteelGlobalsteelindustrytrendsIroninfolkloreKnifemetalMachinabilityPelletizingRolling

RollingmillRustBeltSecondindustrialrevolutionSiliconsteel

SteelabrasiveSteelmillGalvanisingDamascussteelWootzsteelTamahagane,usedinSamuraiswords.Tinplate

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Furtherreading

69. "SteelInterchange"(https://web.archive.org/web/20071222180444/http://aisc.org/MSCTemplate.cfm?Section=Steel_Interchange2&Template=/CustomSource/Faq/SteelInterchange.cfm&FaqID=2311).AmericanInstituteofSteelConstructionInc.(AISC).Archivedfromtheoriginal(http://aisc.org/MSCTemplate.cfm?Section=Steel_Interchange2&Template=/CustomSource/Faq/SteelInterchange.cfm&FaqID=2311)on20071222.Retrieved20070228.

70. "PropertiesofMaragingSteels"(http://steel.keytometals.com/default.aspx?ID=CheckArticle&NM=103).Retrieved20090719.

71. Hadfieldmanganesesteel.(http://answers.com/topic/hadfieldmanganesesteel)Answers.com.McGrawHillDictionaryofScientificandTechnicalTerms,McGrawHillCompanies,Inc.,2003.Retrievedon20070228.

72. "Wingsofsteel:Analloyofironandaluminiumisasgoodastitanium,atatenthofthecost"(http://www.economist.com/news/scienceandtechnology/21642107alloyironandaluminiumgoodtitaniumtenth).TheEconomist.February7,2015.RetrievedFebruary5,2015."E02715"

73. SangHeonKim,HansooKim&NackJ.Kim(February5,2015)."Brittleintermetalliccompoundmakesultrastronglowdensitysteelwithlargeductility"(http://www.nature.com/nature/journal/v518/n7537/full/nature14144.html).Nature(NaturePublishingGroup)518:7779.doi:10.1038/nature14144(https://dx.doi.org/10.1038%2Fnature14144).RetrievedFebruary5,2015."weshowthatanFeAltypebrittlebuthardintermetalliccompound(B2)canbeeffectivelyusedasastrengtheningsecondphaseinhighaluminiumlowdensitysteel,whilealleviatingitsharmfuleffectonductilitybycontrollingitsmorphologyanddispersion."

74. Bringas,JohnE.(2004).HandbookofComparativeWorldSteelStandards:ThirdEdition(https://web.archive.org/web/20070127135646/http://www.astm.org/BOOKSTORE/PUBS/DS67B_SampleChapter.pdf)(PDF)(3rd.ed.).ASTMInternational.p.14.ISBN0803133626.Archivedfromtheoriginal(http://astm.org/BOOKSTORE/PUBS/DS67B_SampleChapter.pdf)(PDF)on20070127.

75. SteelConstructionManual,8thEdition,secondrevisededition,AmericanInstituteofSteelConstruction,1986,ch.1page15

76. Ochshorn,Jonathan(20020611)."Steelin20thCenturyArchitecture"(http://www.ochshorndesign.com/cornell/writings/steel.html).EncyclopediaofTwentiethCenturyArchitecture.Retrieved20100426.

77. Materialsscience.EncyclopdiaBritannica.2007.

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WikimediaCommonshasmediarelatedtoSteel.

LookupsteelinWiktionary,thefreedictionary.

MarkReutter,MakingSteel:SparrowsPointandtheRiseandRuinofAmericanIndustrialMight(https://books.google.com/books?id=bdkUfDoY24QC&printsec=frontcover&dq=Making+Steel:+Sparrows+Point+and+the+Rise+and+Ruin+of+American+Industrial+Might&hl=en&sa=X&ei=NxHuVIe6DIzcoASoICICQ&ved=0CB4Q6AEwAA#v=onepage&q=Making%20Steel%3A%20Sparrows%20Point%20and%20the%20Rise%20and%20Ruin%20of%20American%20Industrial%20Might&f=false)(2005).DiscussionwithMarkReutter,part1of3(http://therealnews.com/t2/index.php?option=com_content&task=view&id=31&Itemid=74&jumival=13277)(February2015),part2of3(http://therealnews.com/t2/index.php?option=com_content&task=view&id=31&Itemid=74&jumival=13284)(February2015),part3of3(http://therealnews.com/t2/index.php?option=com_content&task=view&id=31&Itemid=74&jumival=13298)(March2015),TheRealNewsDuncanBurn,TheEconomicHistoryofSteelmaking,18671939:AStudyinCompetition(http://questia.com/PM.qst?a=o&d=3914930).CambridgeUniversityPress,1961.HarukiyuHasegawa,TheSteelIndustryinJapan:AComparisonwithBritain(http://questia.com/PM.qst?a=o&d=108742046).1996.J.C.CarrandW.Taplin,HistoryoftheBritishSteelIndustry(http://questia.com/PM.qst?a=o&d=808791).HarvardUniversityPress,1962.H.LeeScamehorn,Mill&Mine:TheCf&IintheTwentiethCentury(http://questia.com/PM.qst?a=o&d=94821694).UniversityofNebraskaPress,1992.Needham,Joseph(1986).ScienceandCivilizationinChina:Volume4,Part1&Part3.Taipei:CavesBooks,Ltd.Warren,Kenneth,BigSteel:TheFirstCenturyoftheUnitedStatesSteelCorporation,19012001(http://eh.net/bookreviews/library/0558).UniversityofPittsburghPress,2001.

Externallinks

WorldSteelAssociation(worldsteel)(http://www.worldsteel.org/)steeluniversity.org:OnlinesteeleducationresourcesfromworldsteelandtheUniversityofLiverpool(http://steeluniversity.org/)Hugearchiveonsteels,CambridgeUniversity(http://www.msm.cam.ac.uk/phasetrans/2005/Fealloys.html)CookingwithSteels(http://www.wastedtalent.ca/comic/cookingsteel)MetallurgyfortheNonMetallurgistfromtheAmericanSocietyforMetals(http://books.google.com/books?id=brpxLtdCLYC&pg=PA26&lpg=PA26&d#v=onepage&q&f=true,)MATDATDatabaseofPropertiesofUnalloyed,LowAlloyandHighAlloySteelsobtainedfrompublishedresultsofmaterialtesting(http://www.matdat.com)Newsfeatureon"openhearth"steelworkersattheU.S.SteelFairlessMillsnearPhiladelphia(https://news.google.com/newspapers?id=ArNdAAAAIBAJ&sjid=0V0NAAAAIBAJ&pg=1275%2C782046)

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