Editing Steel (section)

==Contemporary==
{{See also|Steel grades}}
[[File:Bethlehem Steel.jpg|thumb|[[Bethlehem Steel]] in [[Bethlehem, Pennsylvania]] was one of the world's largest manufacturers of steel before its closure in 2003.]]
===Carbon===
{{Main|Carbon steel}}
Modern steels are made with varying combinations of alloy metals to fulfil many purposes.<ref name="materialsengineer" /> [[Carbon steel]], composed simply of [[iron]] and [[carbon]], accounts for 90% of steel production.<ref name="EM2" /> [[Low alloy steel]] is alloyed with other elements, usually [[molybdenum]], [[manganese]], [[chromium]], or [[nickel]], in amounts of up to 10% by weight to improve the hardenability of thick sections.<ref name="EM2" /> [[HSLA steel|High strength low alloy steel]] has small additions (usually < 2% by weight) of other elements, typically 1.5% manganese, to provide additional strength for a modest price increase.<ref>{{cite web |url= http://resources.schoolscience.co.uk/Corus/16plus/steelch3pg1.html |title=High strength low alloy steels |work=SchoolScience.co.uk |access-date=14 August 2007 |archive-date=21 September 2020 |archive-url= https://web.archive.org/web/20200921025905/http://resources.schoolscience.co.uk/Corus/16plus/steelch3pg1.html |url-status=dead}}</ref>

Recent [[corporate average fuel economy]] (CAFE) regulations have given rise to a new variety of steel known as Advanced High Strength Steel (AHSS). This material is both strong and ductile so that vehicle structures can maintain their current safety levels while using less material. There are several commercially available grades of AHSS, such as [[dual-phase steel]], which is heat treated to contain both a ferritic and martensitic microstructure to produce a formable, high strength steel.<ref>{{cite web |title=Dual-phase steel |publisher=Intota Expert Knowledge Services |url= http://www.intota.com/experts.asp?strSearchType=all&strQuery=dual%2Dphase+steel |access-date=1 March 2007 |archive-url= https://web.archive.org/web/20110525170931/http://www.intota.com/experts.asp?strSearchType=all&strQuery=dual%2Dphase+steel |archive-date=25 May 2011 |url-status=dead}}</ref> Transformation Induced Plasticity (TRIP) steel involves special alloying and heat treatments to stabilize amounts of [[austenite]] at room temperature in normally austenite-free low-alloy ferritic steels. By applying strain, the austenite undergoes a [[phase transition]] to martensite without the addition of heat.<ref>{{cite web |last=Werner |first=Ewald |title=Transformation Induced Plasticity in low alloyed TRIP-steels and microstructure response to a complex stress history |url= http://www.wkm.mw.tum.de/Forschung/projekte_html/transtrip.html |access-date=1 March 2007 |url-status=dead |archive-url= https://web.archive.org/web/20071223184922/http://www.wkm.mw.tum.de/Forschung/projekte_html/transtrip.html |archive-date=23 December 2007}}</ref> Twinning Induced Plasticity (TWIP) steel uses a specific type of strain to increase the effectiveness of work hardening on the alloy.<ref>{{cite web |last1=Mirko |first1=Centi |last2=Saliceti |first2=Stefano |title=Transformation Induced Plasticity (TRIP), Twinning Induced Plasticity (TWIP) and Dual-Phase (DP) Steels |publisher=Tampere University of Technology |url= http://www.dimet.unige.it/resta/studenti/2002/27839/26/TWIP,TRIPandDualphase%20mirko.doc |archive-url= https://web.archive.org/web/20080307200557/http://www.dimet.unige.it/resta/studenti/2002/27839/26/TWIP%2CTRIPandDualphase%20mirko.doc |archive-date=7 March 2008 |access-date=1 March 2007 |url-status=dead}}</ref>

Carbon Steels are often [[hot-dip galvanizing|galvanized]], through [[Hot-dip galvanization|hot-dip]] or electroplating in [[zinc]] for protection against rust.<ref>{{cite book |chapter=Galvanic protection |title=[[Encyclopædia Britannica]] |date=2007}}</ref>

===Alloy===
{{Main|Alloy}}
[[File:Alcator C-Mod superstructure forging 1.jpg|thumb|upright|Forging a structural member out of steel]] 
[[File:Rust-AH-2022.jpg|thumb|Cor-Ten rust coating]]
[[Stainless steel]] contains a minimum of 11% chromium, often combined with nickel, to resist [[corrosion]]. Some stainless steels, such as the [[Allotropes of iron|ferritic]] stainless steels are [[magnetic]], while others, such as the [[austenite|austenitic]], are nonmagnetic.<ref>{{cite web |url= http://steel.org |title=Steel Glossary |publisher=[[American Iron and Steel Institute]] |access-date=30 July 2006}}</ref> Corrosion-resistant steels are abbreviated as CRES.

Alloy steels are plain-carbon steels in which small amounts of alloying elements like chromium and vanadium have been added. Some more modern steels include [[tool steel]]s, which are alloyed with large amounts of tungsten and [[cobalt]] or other elements to maximize [[solution hardening]]. This also allows the use of [[precipitation hardening]] and improves the alloy's temperature resistance.<ref name="EM2" /> Tool steel is generally used in axes, drills, and other devices that need a sharp, long-lasting cutting edge. Other special-purpose alloys include [[weathering steel]]s such as Cor-ten, which weather by acquiring a stable, rusted surface, and so can be used un-painted.<ref>{{cite web |url= http://aisc.org/MSCTemplate.cfm?Section=Steel_Interchange2&Template=/CustomSource/Faq/SteelInterchange.cfm&FaqID=2311 |archive-url= https://web.archive.org/web/20071222180444/http://aisc.org/MSCTemplate.cfm?Section=Steel_Interchange2&Template=%2FCustomSource%2FFaq%2FSteelInterchange.cfm&FaqID=2311 |archive-date=22 December 2007 |title=Steel Interchange |publisher=American Institute of Steel Construction |access-date=28 February 2007 |url-status=dead}}</ref> [[Maraging steel]] is alloyed with nickel and other elements, but unlike most steel contains little carbon (0.01%). This creates a very strong but still [[malleability|malleable]] steel.<ref>{{cite web |title=Properties of Maraging Steels |url= http://steel.keytometals.com/default.aspx?ID=CheckArticle&NM=103 |access-date=19 July 2009 |url-status=dead |archive-url= https://web.archive.org/web/20090225211327/http://steel.keytometals.com/default.aspx?ID=CheckArticle&NM=103 |archive-date=25 February 2009}}</ref>

[[Eglin steel]] uses a combination of over a dozen different elements in varying amounts to create a relatively low-cost steel for use in [[bunker buster]] weapons. [[Mangalloy|Hadfield steel]], named after [[Robert Hadfield]], or manganese steel, contains 12–14% manganese which, when abraded, strain-hardens to form a very hard skin which resists wearing. Uses of this particular alloy include [[Continuous track|tank tracks]], [[bulldozer#Blade|bulldozer blade]] edges, and cutting blades on the [[jaws of life]].<ref name="auto1">{{cite book |title=Sheffield Steel and America: A Century of Commercial and Technological Independence |publisher=Cambridge University Press |date=1987 |editor-last=Tweedale |editor-first=Geoffrey |pages=57–62}}</ref>

=== Standards ===
Most of the more commonly used steel alloys are categorized into various grades by standards organizations. For example, the [[Society of Automotive Engineers]] has a series of [[SAE steel grades|grades]] defining many types of steel.<ref name="bringas">{{Cite book |last=Bringas |first=John E. |title=Handbook of Comparative World Steel Standards: Third Edition |publisher=ASTM International |page=14 |date=2004 |edition=3rd. |url= http://astm.org/BOOKSTORE/PUBS/DS67B_SampleChapter.pdf |archive-url= https://web.archive.org/web/20070127135646/http://www.astm.org/BOOKSTORE/PUBS/DS67B_SampleChapter.pdf |archive-date=27 January 2007 |isbn=0-8031-3362-6 |url-status=dead}}</ref> The [[ASTM International|American Society for Testing and Materials]] has a separate set of standards, which define alloys such as [[A36 steel]], the most commonly used structural steel in the United States.<ref>Steel Construction Manual, 8th Edition, second revised edition, American Institute of Steel Construction, 1986, ch. 1 pp. 1–5</ref> The [[Japanese Industrial Standards|JIS]] also defines a series of steel grades that are being used extensively in [[Japan]] as well as in developing countries.