Editing Steel (section)

==History==
{{Main|History of ferrous metallurgy|History of the steel industry (1850–1970)}}
===Ancient===
[[File:Bas fourneau.png|thumb|upright|[[Bloomery]] smelting during the [[Middle Ages]] in the 5th to 15th centuries]]
Steel was known in antiquity and was produced in [[Bloomery|bloomeries]] and [[crucible]]s.{{sfnp|Davidson|1994|p=20}}<ref name="materials.iisc.ernet.in">{{Cite news |author1=Srinivasan, S. |author2=Ranganathan, S. |url= https://materials.iisc.ernet.in/~wootz/heritage/WOOTZ.htm |title=The Sword in Anglo-Saxon England: Its Archaeology and Literature |date=1994 |publisher=Department of Metallurgy, Indian Institute of Science |location=Bangalore |isbn=0-85115-355-0 |archive-url= https://web.archive.org/web/20181119033451/http://materials.iisc.ernet.in/~wootz/heritage/WOOTZ.htm |archive-date=19 November 2018}}</ref>

The earliest known production of steel is seen in pieces of [[Iron ware|ironware]] excavated from an [[archaeological site]] in [[Anatolia]] ([[Kaman-Kalehöyük]]) which are nearly 4,000 years old, dating from 1800&nbsp;BC.<ref>{{cite journal |last=Akanuma |first=H. |title=The significance of the composition of excavated iron fragments taken from Stratum III at the site of Kaman-Kalehöyük, Turkey |journal=Anatolian Archaeological Studies |volume=14 |pages=147–158 |date=2005 |publisher=Japanese Institute of Anatolian Archaeology |place=Tokyo}}</ref><ref>{{cite news |title=Ironware piece unearthed from Turkey found to be oldest steel |url= http://www.hindu.com/thehindu/holnus/001200903261611.htm |access-date=13 August 2022 |location=Chennai |work=[[The Hindu]] |date=26 March 2009 |url-status=dead |archive-url= https://web.archive.org/web/20090329111924/http://www.hindu.com/thehindu/holnus/001200903261611.htm |archive-date=29 March 2009}}</ref> 

[[Wootz steel]] was developed in [[Southern India]] and [[Sri Lanka]] in the 1st millennium BCE.<ref name="materials.iisc.ernet.in" /> Metal production sites in [[Sri Lanka]] employed wind furnaces driven by the monsoon winds, capable of producing high-carbon steel. Large-scale wootz steel production in [[Ancient India|India]] using crucibles occurred by the sixth century&nbsp;BC, the pioneering precursor to modern steel production and metallurgy.{{sfnp|Davidson|1994|p=20}}<ref name="materials.iisc.ernet.in" />

High-carbon steel was produced in [[British Iron Age|Britain]] at [[Broxmouth|Broxmouth Hillfort]] from 490–375 BC,<ref>{{Cite news |title=East Lothian's Broxmouth fort reveals edge of steel |url= https://www.bbc.co.uk/news/uk-scotland-edinburgh-east-fife-25734877 |work=[[BBC News]] |date=15 January 2014}}</ref><ref>{{cite book |url= https://www.socantscot.org/product/an-inherited-place/ |title=An Inherited Place: Broxmouth Hillfort and the South-East Scottish Iron Age |date=2013 |publisher=Society of Antiquaries of Scotland |isbn=978-1-908332-05-9}}</ref> and ultrahigh-carbon steel was produced in the [[Netherlands]] from the 2nd-4th centuries AD.<ref>{{cite journal |url= https://www.sciencedirect.com/science/article/abs/pii/S0305440304000202 |journal=Journal of Archaeological Science |volume=31 |issue=8 |date=2004 |title=A Germanic ultrahigh carbon steel punch of the Late Roman-Iron Age |last1=Godfrey |first1=Evelyne |display-authors=etal |doi=10.1016/j.jas.2004.02.002 |pages=1117–1125 |bibcode=2004JArSc..31.1117G}}</ref> The Roman author [[Horace]] identifies steel weapons such as the ''[[falcata]]'' in the [[Iberian Peninsula]], while [[Noric steel]] was used by the [[Military of ancient Rome|Roman military]].<ref>"Noricus ensis", [[Horace]], Odes, i. 16.9</ref>

The [[History of China#Ancient China|Chinese]] of the [[Warring States period]] (403&ndash;221&nbsp;BC) had [[quench|quench-hardened]] steel,<ref>{{cite book |last=Wagner |first=Donald B. |date=1993 |title=Iron and Steel in Ancient China |edition=2nd |location=Leiden |publisher=E. J. Brill |isbn=90-04-09632-9 |page=243}}</ref> while Chinese of the [[Han dynasty]] (202&nbsp;BC&mdash;AD&nbsp;220) created steel by melting together wrought iron with cast iron, thus producing a carbon-intermediate steel by the 1st century&nbsp;AD.<ref name="needham volume 4 part 3 563g">{{cite book |last=Needham |first=Joseph |date=1986 |title=Science and Civilization in China: Volume 4, Part 3, Civil Engineering and Nautics |location=Taipei |publisher=Caves Books |page=563}}</ref><ref name="gernet 69">Gernet, Jacques (1982). ''A History of Chinese Civilization''. Cambridge: Cambridge University Press. p. 69. {{ISBN|0-521-49781-7}}.</ref>

There is evidence that [[carbon steel]] was made in Western [[Tanzania]] by the ancestors of the [[Haya people]] as early as 2,000 years ago by a complex process of "pre-heating" allowing temperatures inside a furnace to reach 1300 to 1400&nbsp;°C.<ref name="SchmidtCS">{{Cite journal |last1=Schmidt |first1=Peter |last2=Avery |first2=Donald |date=1978 |title=Complex Iron Smelting and Prehistoric Culture in Tanzania |journal=Science |volume=201 |issue=4361 |pages=1085–1089 |jstor=1746308 |doi=10.1126/science.201.4361.1085 |pmid=17830304 |bibcode=1978Sci...201.1085S |s2cid=37926350}}</ref><ref name=":3">{{Cite journal |last1=Schmidt |first1=Peter |last2=Avery |first2=Donald |date=1983 |title=More Evidence for an Advanced Prehistoric Iron Technology in Africa |journal=Journal of Field Archaeology |volume=10 |issue=4 |pages=421–434 |doi=10.1179/009346983791504228}}</ref><ref name=":0">{{Cite book |title=Historical Archaeology: A Structural Approach in an African Culture |last=Schmidt |first=Peter |publisher=Greenwood Press |date=1978 |location=Westport, Connecticut}}</ref><ref>{{Cite book |title=The Culture and Technology of African Iron Production |last1=Avery |first1=Donald |last2=Schmidt |first2=Peter |publisher=University of Florida Press |date=1996 |location=Gainesville, Florida |pages=267–276 |chapter=Preheating: Practice or illusion}}</ref><ref>{{Cite book |title=A Companion to African History |last=Schmidt |first=Peter |publisher=Wiley Blackwell |date=2019 |editor-last=Worger |editor-first=W. |location=Hoboken, New Jersey |pages=267–288 |chapter=Science in Africa: A history of ingenuity and invention in African iron technology |editor-last2=Ambler |editor-first2=C. |editor-last3=Achebe |editor-first3=N.}}</ref><ref>{{Cite book |last=Childs |first=S. Terry |chapter=Technological history and culture in western Tanzania |title=The Culture and Technology of African Iron Production |publisher=University of Florida Press |date=1996 |editor-last=Schmidt |editor-first=P. |location=Gainesville, Florida}}</ref>

===Wootz and Damascus===
{{Main|Wootz steel|Damascus steel}}

Evidence of the earliest production of high carbon steel in [[South Asia]] is found in [[Kodumanal]] in [[Tamil Nadu]], the [[Golconda]] area in [[Andhra Pradesh]] and [[Karnataka]], regions of [[India]], as well as in [[Samanalawewa]] and Dehigaha Alakanda, regions of [[Sri Lanka]].<ref>{{cite news |last=Wilford |first=John Noble |title=Ancient Smelter Used Wind To Make High-Grade Steel |work=The New York Times |date=6 February 1996 |url= https://www.nytimes.com/1996/02/06/science/ancient-smelter-used-wind-to-make-high-grade-steel.html?n=Top%2FNews%2FScience%2FTopics%2FArchaeology%20and%20Anthropology}}</ref> This came to be known as [[wootz steel]], produced in South India by about the sixth century&nbsp;BC and exported globally.<ref name="SR_IISc">{{cite book |last1=Srinivasan |first1=Sharada |last2=Ranganathan |first2=Srinivasa |title=India's Legendary Wootz Steel: An Advanced Material of the Ancient World |date=2004 |publisher=National Institute of Advanced Studies |oclc=82439861 |url= http://materials.iisc.ernet.in/~wootz/heritage/WOOTZ.htm |access-date=5 December 2014 |archive-url= https://web.archive.org/web/20190211082829/http://materials.iisc.ernet.in/~wootz/heritage/WOOTZ.htm |archive-date=11 February 2019 |url-status=dead}}</ref><ref name="ann">{{cite journal |last=Feuerbach |first=Ann |title=An investigation of the varied technology found in swords, sabres and blades from the Russian Northern Caucasus |url= https://www.es.ucl.ac.uk/iams/jour_25/iams25_Feuerbach.pdf |journal=IAMS |volume=25 |date=2005 |pages=27–43 (p. 29) |url-status=dead |archive-url= https://web.archive.org/web/20110430044256/https://www.es.ucl.ac.uk/iams/jour_25/iams25_Feuerbach.pdf |archive-date=30 April 2011}}</ref> The steel technology existed prior to 326&nbsp;BC in the region as they are mentioned in literature of [[Sangam literature|Sangam Tamil]], [[Arabic]], and [[Latin]] as the finest steel in the world exported to the Roman, Egyptian, Chinese and Arab worlds at that time – what they called ''Seric Iron''.<ref>{{cite journal |last=Srinivasan |first=Sharada |date=1994 |title=Wootz crucible steel: a newly discovered production site in South India |journal=Papers from the Institute of Archaeology |volume=5 |pages=49–59 |doi=10.5334/pia.60 |doi-access=free}}</ref> A [[Tissamaharama Tamil Brahmi inscription|200 BC Tamil trade guild in Tissamaharama]], in the South East of Sri Lanka, brought with them some of the oldest iron and steel artifacts and production processes to the island from the [[classical antiquity|classical period]].<ref>Hobbies – Volume 68, Issue 5 – p. 45. Lightner Publishing Company (1963)</ref><ref name="Mahathevan">{{cite news |url= http://www.hindu.com/2010/06/24/stories/2010062451701100.htm |archive-url= https://web.archive.org/web/20100701211040/http://www.hindu.com/2010/06/24/stories/2010062451701100.htm |url-status=dead |archive-date=1 July 2010 |title=An epigraphic perspective on the antiquity of Tamil |last=Mahathevan |first=Iravatham |date=24 June 2010 |work=[[The Hindu]] |access-date=31 October 2010}}</ref><ref name="Ragupathy">{{cite news |url= http://www.tamilnet.com/art.html?catid=79&artid=32303 |title=Tissamaharama potsherd evidences ordinary early Tamils among population |last=Ragupathy |first=P. |date=28 June 2010 |work=Tamilnet |access-date=31 October 2010}}</ref> The Chinese and locals in [[Anuradhapura]], Sri Lanka had also adopted the production methods of creating wootz steel from the [[Chera Dynasty]] Tamils of South India by the 5th century&nbsp;AD.<ref name="needham volume 4 part 1 282">{{cite book |last=Needham |first=Joseph |date=1986 |title=Science and Civilization in China: Volume 4, Part 1, Civil Engineering and Nautics |location=Taipei |publisher=Caves Books |page=282 |isbn=0-521-05802-3 |url= https://monoskop.org/images/7/70/Needham_Joseph_Science_and_Civilisation_in_China_Vol_4-1_Physics_and_Physical_Technology_Physics.pdf |access-date=4 August 2017 |archive-url= https://web.archive.org/web/20170703010030/https://monoskop.org/images/7/70/Needham_Joseph_Science_and_Civilisation_in_China_Vol_4-1_Physics_and_Physical_Technology_Physics.pdf |archive-date=3 July 2017 |url-status=dead}}</ref><ref name="Ancient and Mediaeval India. Vol.2 by Charlotte Speir Manning p.365">{{Cite book |url= https://books.google.com/books?id=nmESJR3a0RYC&pg=PA365 |title=Ancient and Mediæval India. Volume 2 |isbn=978-0-543-92943-3 |last1=Manning |first1=Charlotte Speir}}</ref> In Sri Lanka, this early steel-making method employed a unique wind furnace, driven by the monsoon winds, capable of producing high-carbon steel.<ref name="Juleff1">{{cite journal |last=Juleff |first=G. |title=An ancient wind powered iron smelting technology in Sri Lanka |journal=[[Nature (journal)|Nature]] |volume=379 |issue=3 |pages=60–63 |date=1996 |doi=10.1038/379060a0 |bibcode=1996Natur.379...60J |s2cid=205026185}}</ref><ref name="Herbert Henery Coghlan 1977 pp 99-100">Coghlan, Herbert Henery. (1977). ''Notes on prehistoric and early iron in the Old World''. Oxprint. pp. 99–100</ref> Since the technology was acquired from the [[Tamilians]] from South India,<ref name="Ancient and Medieval India. Vol.2 by Charlotte Speir Manning p.365">{{Cite book |last1=Manning |first1=Charlotte Speir |url= https://books.google.com/books?id=nmESJR3a0RYC&pg=PA365 |title=Ancient and Medieval India. Volume 2 |isbn=978-0-543-92943-3}}</ref> the origin of steel technology in India can be conservatively estimated at 400&ndash;500&nbsp;BC.<ref name="SR_IISc" /><ref name="Herbert Henery Coghlan 1977 pp 99-100" />

The manufacture of [[wootz steel]] and [[Damascus steel]], famous for its durability and ability to hold an edge, may have been taken by the Arabs from Persia, who took it from India. {{cns|It was originally created from several different materials including various [[trace element]]s, apparently ultimately from the writings of [[Zosimos of Panopolis]].|date=December 2023}} In 327&nbsp;BC, [[Alexander the Great]] was rewarded by the defeated King [[Porus the Elder|Porus]], not with gold or silver but with 30&nbsp;pounds of steel.<ref>{{cite book |last=Durant |first=Will |title=The Story of Civilization, Our Oriental Heritage |date=1942 |publisher=Simon & Schuster |isbn=0-671-54800-X |page=529 |url= https://archive.org/details/storyofcivilizat035369mbp/page/529}}</ref> A recent study has speculated that [[carbon nanotubes]] were included in its structure, which might explain some of its legendary qualities, though, given the technology of that time, such qualities were produced by chance rather than by design.<ref>{{cite journal |title=Sharpest cut from nanotube sword |first=Katharine |last=Sanderson |date=15 November 2006 |doi=10.1038/news061113-11 |journal=Nature News |s2cid=136774602 |doi-access=free}}</ref> Natural wind was used where the soil containing iron was heated by the use of wood. The [[ancient Sinhalese]] managed to extract a ton of steel for every 2&nbsp;tons of soil,<ref name="Juleff1" /> a remarkable feat at the time. One such furnace was found in Samanalawewa and archaeologists were able to produce steel as the ancients did.<ref name="Juleff1" /><ref>{{cite journal |last1=Wayman |first1=M. L. |last2=Juleff |first2=G. |title=Crucible Steelmaking in Sri Lanka |journal=Historical Metallurgy |volume=33 |issue=1 |date=1999 |page=26}}</ref>

[[Crucible steel]], formed by slowly heating and cooling pure iron and carbon (typically in the form of charcoal) in a crucible, was produced in [[Merv]] by the 9th to 10th century&nbsp;AD.<ref name="ann" /> In the 11th century, there is evidence of the production of steel in [[Song dynasty|Song China]] using two techniques: a "berganesque" method that produced inferior, inhomogeneous steel, and a precursor to the modern [[Bessemer process]] that used partial [[decarburization]] via repeated forging under a [[cold blast]].<ref>{{cite journal |last=Hartwell |first=Robert |title=Markets, Technology and the Structure of Enterprise in the Development of the Eleventh Century Chinese Iron and Steel Industry |journal=[[Journal of Economic History]] |volume=26 |date=1966 |pages=53–54 |doi=10.1017/S0022050700061842 |s2cid=154556274}}</ref>

===Modern===
[[File:Bessemer Converter Sheffield.jpg|thumb|upright|A [[Bessemer process|Bessemer converter]] in [[Sheffield]], England]]
Since the 17th century, the first step in European steel production has been the smelting of iron ore into [[pig iron]] in a [[blast furnace]].<ref name="Tylecote">{{cite book |last=Tylecote |first=R. F. |date=1992 |title=A History of Metallurgy |edition=2nd |publisher=Institute of Materials |location=London |pages=95–99, 102–105 |isbn=0-901462-88-8}}</ref>{{page needed|date=April 2024}} Originally employing charcoal, modern methods use [[coke (fuel)|coke]], which has proven more economical.<ref>{{cite book |last=Raistrick |first=A. |date=1953 |title=A Dynasty of Ironfounders}}</ref>{{page needed|date=April 2024}}<ref>{{cite book |last=Hyde |first=C. K. |date=1977 |title=Technological Change and the British Iron Industry |publisher=Princeton University Press}}</ref>{{page needed|date=April 2024}}<ref>{{cite book |last=Trinder |first=B. |date=2000 |title=The Industrial Revolution in Shropshire |edition=3rd |location=Chichester |publisher=Phillimore |isbn=9781860771330}}</ref>{{page needed|date=April 2024}}

====Processes starting from bar iron====
{{Main|Blister steel|Crucible steel}}
In these processes, [[pig iron]] made from raw iron ore was refined (fined) in a [[finery forge]] to produce [[bar iron]], which was then used in steel-making.<ref name="Tylecote" />

The production of steel by the [[cementation process]] was described in a treatise published in Prague in 1574 and was in use in [[Nuremberg]] from 1601. A similar process for [[case hardening]] armour and files was described in a book published in [[Naples]] in 1589. The process was introduced to England in about 1614 and used to produce such steel by Sir [[Basil Brooke (metallurgist)|Basil Brooke]] at [[Coalbrookdale]] during the 1610s.{{sfnp|Barraclough|1984a|pp=48–52}}

The raw material for this process were bars of iron. During the 17th century, it was realized that the best steel came from [[oregrounds iron]] of a region north of [[Stockholm]], Sweden. This was still the usual raw material source in the 19th century, almost as long as the process was used.<ref>{{cite journal |last=King |first=P. W. |title=The Cartel in Oregrounds Iron: trading in the raw material for steel during the eighteenth century |journal=Journal of Industrial History |volume=6 |issue=1 |date=2003 |pages=25–49}}</ref><ref name="britannicaironandsteel">{{cite book |chapter=Iron and steel industry |title=Encyclopædia Britannica |date=2007}}</ref>

Crucible steel is steel that has been melted in a [[crucible]] rather than having been [[forging|forged]], with the result that it is more homogeneous. Most previous furnaces could not reach high enough temperatures to melt the steel. The early modern crucible steel industry resulted from the invention of [[Benjamin Huntsman]] in the 1740s. Blister steel (made as above) was melted in a crucible or in a furnace, and cast (usually) into ingots.<ref name="britannicaironandsteel" />{{sfnp|Barraclough|1984b}}{{page needed|date=April 2024}}

====Processes starting from pig iron====
[[File:Siemens Martin Ofen Brandenburg.jpg|thumb|An [[open hearth furnace]] in the Museum of Industry in [[Brandenburg]], Germany]]
[[File:Allegheny Ludlum steel furnace.jpg|thumb|White-hot steel pouring out of an electric arc furnace in [[Brackenridge, Pennsylvania]]]]
The modern era in [[steelmaking]] began with the introduction of [[Henry Bessemer]]'s [[Bessemer process|process]] in 1855, the raw material for which was pig iron.<ref>{{cite book |title=History of the Manufacture of Iron in All Ages |last=Swank |first=James Moore |isbn=0-8337-3463-6 |date=1892 |publisher=Burt Franklin}}</ref> His method let him produce steel in large quantities cheaply, thus [[mild steel]] came to be used for most purposes for which wrought iron was formerly used.<ref>{{cite book |chapter=Bessemer process |chapter-url= https://www.britannica.com/technology/Bessemer-process |volume=2 |page=168 |title=[[Encyclopædia Britannica]] |edition=online |date=2005}}</ref> The Gilchrist-Thomas process (or ''basic Bessemer process'') was an improvement to the Bessemer process, made by lining the converter with a [[basic (chemistry)|basic]] material to remove phosphorus.

Another 19th-century steelmaking process was the [[Siemens-Martin process]], which complemented the Bessemer process.<ref name="britannicaironandsteel" /> It consisted of co-melting bar iron (or steel scrap) with pig iron.

These methods of steel production were rendered obsolete by the Linz-Donawitz process of [[basic oxygen steelmaking]] (BOS), developed in 1952,<ref name="zs">{{cite news |last1=Sherman |first1=Zander |title=How my great-grandfather's Dofasco steel empire rose and fell, and his descendants with it |url= https://www.theglobeandmail.com/business/rob-magazine/article-how-my-great-grandfathers-dofasco-steel-empire-rose-and-fell-and-his/ |work=[[The Globe and Mail]] |date=4 September 2019}}</ref> and other oxygen steel making methods. Basic oxygen steelmaking is superior to previous steelmaking methods because the oxygen pumped into the furnace limited impurities, primarily nitrogen, that previously had entered from the air used,<ref>{{cite book |chapter=Basic oxygen process |title=[[Encyclopædia Britannica]] |date=2007}}</ref> and because, with respect to the open hearth process, the same quantity of steel from a BOS process is manufactured in one-twelfth the time.<ref name="zs" /> Today, [[electric arc furnace]]s (EAF) are a common method of reprocessing [[scrap|scrap metal]] to create new steel. They can also be used for converting pig iron to steel, but they use a lot of electrical energy (about 440 kWh per&nbsp;metric ton), and are thus generally only economical when there is a plentiful supply of cheap electricity.{{sfnp|Fruehan|Wakelin|1998|pp=48–52}}