Editing Alloy (section)

== History and examples ==
[[file:Meteorite and a meteoritic iron hatchet.JPG|thumb|left|A [[meteorite]] and a hatchet that was forged from [[meteoric iron]]. Evidence of the [[Widmanstätten pattern]]s from the original meteorite used to make the hatchet's head can be seen on its surface.]]

=== Meteoric iron ===

The use of alloys by humans started with the use of [[meteoric iron]], a naturally occurring alloy of nickel and iron. It is the main constituent of [[iron meteorite]]s. As no metallurgic processes were used to separate iron from nickel, the alloy was used as it was.<ref>{{ cite journal | author = Rickard, T.A. | title = The Use of Meteoric Iron | journal =Journal of the Royal Anthropological Institute |volume = 71 | issue = 1/2 | year = 1941 | pages = 55–66 | doi = 10.2307/2844401 | jstor =2844401 }}</ref> Meteoric iron could be forged from a red heat to make objects such as tools, weapons, and nails. In many cultures it was shaped by cold hammering into knives and arrowheads. They were often used as anvils. Meteoric iron was very rare and valuable, and difficult for ancient people to [[cold working|work]].<ref>[[#Buchwald|Buchwald]], pp. 13–22</ref>

=== Bronze and brass ===
[[file:Bronzebeile.JPG|thumb|Bronze axe 1100&nbsp;BC]]
[[file:Türzieher Bremen 1405.JPG|thumb|left|A bronze doorknocker]]

Iron is usually found as [[iron ore]] on Earth, except for one deposit of [[native iron]] in [[Greenland]], which was used by the [[Inuit]].<ref>[[#Buchwald|Buchwald]], pp. 35–37</ref> Native copper, however, was found worldwide, along with silver, gold, and [[platinum]], which were also used to make tools, jewelry, and other objects since Neolithic times. Copper was the hardest of these metals, and the most widely distributed. It became one of the most important metals to the ancients. Around 10,000 years ago in the highlands of [[Anatolia]] (Turkey), humans learned to [[smelting|smelt]] metals such as copper and [[tin]] from [[ore]]. Around 2500 BC, people began alloying the two metals to form bronze, which was much harder than its ingredients. Tin was rare, however, being found mostly in Great Britain. In the Middle East, people began alloying copper with [[zinc]] to form brass.<ref>Buchwald, pp. 39–41</ref> Ancient civilizations took into account the mixture and the various properties it produced, such as [[hardness]], toughness and melting point, under various conditions of [[temperature]] and [[work hardening]], developing much of the information contained in modern [[Phase diagram|alloy phase diagrams]].<ref name=r1/> For example, arrowheads from the Chinese [[Qin dynasty]] (around 200 BC) were often constructed with a hard bronze-head, but a softer bronze-tang, combining the alloys to prevent both dulling and breaking during use.<ref>[https://www.pbs.org/wgbh/nova/ancient/emperors-ghost-army.html Emperor's Ghost Army] {{webarchive|url=https://web.archive.org/web/20171101065925/http://www.pbs.org/wgbh/nova/ancient/emperors-ghost-army.html |date=2017-11-01 }}. pbs.org. November 2014</ref>

=== Amalgams ===

[[Mercury (element)|Mercury]] has been smelted from [[cinnabar]] for thousands of years. Mercury dissolves many metals, such as gold, silver, and tin, to form [[amalgam (chemistry)|amalgams]] (an alloy in a soft paste or liquid form at ambient temperature). Amalgams have been used since 200 BC in China for [[gilding]] objects such as [[armor]] and [[mirror]]s with precious metals. The ancient Romans often used mercury-tin amalgams for gilding their armor. The amalgam was applied as a paste and then heated until the mercury vaporized, leaving the gold, silver, or tin behind.<ref>Rapp, George (2009) [https://books.google.com/books?id=ed0yC98aAKYC&pg=PA180 ''Archaeomineralogy''] {{webarchive|url=https://web.archive.org/web/20160428005752/https://books.google.com/books?id=ed0yC98aAKYC&pg=PA180 |date=2016-04-28 }}. Springer. p. 180. {{ISBN|3-540-78593-0}}</ref> Mercury was often used in mining, to extract precious metals like gold and silver from their ores.<ref>Miskimin, Harry A.  (1977) [https://books.google.com/books?id=QE04AAAAIAAJ&pg=PA31 ''The economy of later Renaissance Europe, 1460–1600''] {{webarchive|url=https://web.archive.org/web/20160505181953/https://books.google.com/books?id=QE04AAAAIAAJ&pg=PA31 |date=2016-05-05 }}. Cambridge University Press. p. 31. {{ISBN|0-521-29208-5}}.</ref>

=== Precious metals ===
[[file:25 litrai en électrum représentant un trépied delphien.jpg|thumb|[[Electrum]], a natural alloy of silver and gold, was often used for making coins]]

Many ancient civilizations alloyed metals for purely aesthetic purposes. In ancient [[Egypt]] and [[Mycenae]], gold was often alloyed with copper to produce red-gold, or iron to produce a bright burgundy-gold. Gold was often found alloyed with silver or other metals to produce various types of [[colored gold]]. These metals were also used to strengthen each other, for more practical purposes. Copper was often added to silver to make [[sterling silver]], increasing its strength for use in dishes, silverware, and other practical items. Quite often, precious metals were alloyed with less valuable substances as a means to deceive buyers.<ref>Nicholson, Paul T. and Shaw, Ian (2000) [https://books.google.com/books?id=Vj7A9jJrZP0C&pg=PA164 ''Ancient Egyptian materials and technology''] {{webarchive|url=https://web.archive.org/web/20160502125054/https://books.google.com/books?id=Vj7A9jJrZP0C&pg=PA164 |date=2016-05-02 }}. Cambridge University Press. pp. 164–167. {{ISBN|0-521-45257-0}}.</ref> Around 250 BC, [[Archimedes]] was commissioned by the King of [[Syracuse, Sicily|Syracuse]] to find a way to check the purity of the gold in a crown, leading to the famous bath-house shouting of "Eureka!" upon the discovery of [[Archimedes' principle]].<ref>Kay, Melvyn (2008) [https://books.google.com/books?id=xCtAV_MCD1EC&pg=PA45 ''Practical Hydraulics''] {{webarchive|url=https://web.archive.org/web/20160603085124/https://books.google.com/books?id=xCtAV_MCD1EC&pg=PA45 |date=2016-06-03 }}. Taylor and Francis. p. 45. {{ISBN|0-415-35115-4}}.</ref>

=== Pewter ===

The term [[pewter]] covers a variety of alloys consisting primarily of tin. As a pure metal, tin is much too soft to use for most practical purposes. However, during the [[Bronze Age]], tin was a rare metal in many parts of Europe and the Mediterranean, so it was often valued higher than gold. To make jewellery, cutlery, or other objects from tin, workers usually alloyed it with other metals to increase strength and hardness. These metals were typically [[lead]], [[antimony]], [[bismuth]] or copper. These solutes were sometimes added individually in varying amounts, or added together, making a wide variety of objects, ranging from practical items such as dishes, surgical tools, candlesticks or funnels, to decorative items like ear rings and hair clips.

The earliest examples of pewter come from ancient Egypt, around 1450 BC. The use of pewter was widespread across Europe, from France to Norway and Britain (where most of the ancient tin was mined) to the Near East.<ref>Hull, Charles (1992) ''Pewter''. Shire Publications. pp. 3–4; {{ISBN|0-7478-0152-5}}</ref> The alloy was also used in China and the Far East, arriving in Japan around 800 AD, where it was used for making objects like ceremonial vessels, tea canisters, or chalices used in [[shinto]] shrines.<ref>Brinkley, Frank (1904) ''Japan and China: Japan, its history, arts, and literature''. Oxford University. p. 317</ref>

=== Iron ===
[[file:Chinese fining.png|thumb|Puddling in China, {{circa|1637}}. Opposite to most alloying processes, liquid pig-iron is poured from a blast furnace into a container and stirred to remove carbon, which diffuses into the air forming carbon dioxide, leaving behind a [[mild steel]] to wrought iron]]

The first known smelting of iron began in [[Anatolia]], around 1800 BC. Called the [[bloomery|bloomery process]], it produced very soft but [[ductile]] [[wrought iron]]. By 800 BC, iron-making technology had spread to Europe, arriving in Japan around 700 AD. [[Pig iron]], a very hard but brittle alloy of iron and carbon, was being produced in [[History of China#Shang dynasty (1600–1046 BC)|China]] as early as 1200 BC, but did not arrive in Europe until the Middle Ages. Pig iron has a lower melting point than iron, and was used for making [[cast-iron]]. However, these metals found little practical use until the introduction of [[crucible steel]] around 300 BC. These steels were of poor quality, and the introduction of [[pattern welding]], around the 1st century AD, sought to balance the extreme properties of the alloys by laminating them, to create a tougher metal. Around 700 AD, the Japanese began folding bloomery-steel and cast-iron in alternating layers to increase the strength of their swords, using clay fluxes to remove [[slag]] and impurities. This method of [[Japanese swordsmithing]] produced one of the purest steel-alloys of the ancient world.<ref name=r1>Smith, Cyril (1960) ''History of metallography''. MIT Press. pp. 2–4. {{ISBN|0-262-69120-5}}.</ref>

While the use of iron started to become more widespread around 1200 BC, mainly because of interruptions in the trade routes for tin, the metal was much softer than bronze. However, very small amounts of steel, (an alloy of iron and around 1% carbon), was always a byproduct of the bloomery process. The ability to modify the hardness of steel by heat treatment had been known since 1100 BC, and the rare material was valued for the manufacture of tools and weapons. Because the ancients could not produce temperatures high enough to melt iron fully, the production of steel in decent quantities did not occur until the introduction of [[blister steel]] during the Middle Ages. This method introduced carbon by heating wrought iron in charcoal for long periods of time, but the absorption of carbon in this manner is extremely slow thus the penetration was not very deep, so the alloy was not homogeneous. In 1740, [[Benjamin Huntsman]] began melting blister steel in a crucible to even out the carbon content, creating the first process for the mass production of [[tool steel]]. Huntsman's process was used for manufacturing tool steel until the early 1900s.<ref name="George Adam Roberts Page 2-3">Roberts, George Adam; Krauss, George; Kennedy, Richard and Kennedy, Richard L. (1998) [https://books.google.com/books?id=ScphevR_eP8C&pg=PA2 ''Tool steels''] {{webarchive|url=https://web.archive.org/web/20160424215509/https://books.google.com/books?id=ScphevR_eP8C&pg=PA2 |date=2016-04-24 }}. ASM International. pp. 2–3. {{ISBN|0-87170-599-0}}.</ref>

The introduction of the blast furnace to Europe in the Middle Ages meant that people could produce pig iron in much higher volumes than wrought iron. Because pig iron could be melted, people began to develop processes to reduce carbon in liquid pig iron to create steel. [[Puddling (metallurgy)|Puddling]] had been used in China since the first century, and was introduced in Europe during the 1700s, where molten pig iron was stirred while exposed to the air, to remove the carbon by [[oxidation]]. In 1858, [[Henry Bessemer]] developed a process of steel-making by blowing hot air through liquid pig iron to reduce the carbon content. The [[Bessemer process]] led to the first large scale manufacture of steel.<ref name="George Adam Roberts Page 2-3"/>

Steel is an alloy of iron and carbon, but the term ''[[alloy steel]]'' usually only refers to steels that contain other elements— like [[vanadium]], [[molybdenum]], or [[cobalt]]—in amounts sufficient to alter the properties of the base steel. Since ancient times, when steel was used primarily for tools and weapons, the methods of producing and working the metal were often closely guarded secrets. Even long after the [[Age of Enlightenment]], the steel industry was very competitive and manufacturers went through great lengths to keep their processes confidential, resisting any attempts to scientifically analyze the material for fear it would reveal their methods. For example, the people of [[Sheffield]], a center of steel production in England, were known to routinely bar visitors and tourists from entering town to deter [[industrial espionage]]. Thus, almost no metallurgical information existed about steel until 1860. Because of this lack of understanding, steel was not generally considered an alloy until the decades between 1930 and 1970 (primarily due to the work of scientists like [[William Chandler Roberts-Austen]], [[Adolf Martens]], and [[Edgar Bain]]), so "alloy steel" became the popular term for ternary and quaternary steel-alloys.<ref>''Sheffield Steel and America: A Century of Commercial and Technological Independence'' By Geoffrey Tweedale – Cambridge University Press 1987 Page 57–62</ref><ref>''Experimental Techniques in Materials and Mechanics'' By C. Suryanarayana – CRC Press 2011 p. 202</ref>

After Benjamin Huntsman developed his crucible steel in 1740, he began experimenting with the addition of elements like [[manganese]] (in the form of a high-manganese pig-iron called ''[[spiegeleisen]]''), which helped remove impurities such as phosphorus and oxygen; a process adopted by Bessemer and still used in modern steels (albeit in concentrations low enough to still be considered carbon steel).<ref>''Tool Steels, 5th Edition'' By George Adam Roberts, Richard Kennedy, G. Krauss – ASM International 1998 p. 4</ref> Afterward, many people began experimenting with various alloys of steel without much success. However, in 1882, [[Robert Hadfield]], being a pioneer in steel metallurgy, took an interest and produced a steel alloy containing around 12% manganese. Called [[mangalloy]], it exhibited extreme hardness and toughness, becoming the first commercially viable alloy-steel.<ref>{{cite book|author=Bramfitt, B.L.|title=Metallographer's Guide: Practice and Procedures for Irons and Steels|url=https://books.google.com/books?id=hoM8VJHTt24C&pg=PA13|year=2001|publisher=ASM International|isbn=978-1-61503-146-7|pages=13–|url-status=live|archive-url=https://web.archive.org/web/20160502154559/https://books.google.com/books?id=hoM8VJHTt24C&pg=PA13|archive-date=2016-05-02}}</ref> Afterward, he created silicon steel, launching the search for other possible alloys of steel.<ref>''Sheffield Steel and America: A Century of Commercial and Technological Independence'' By Geoffrey Tweedale – Cambridge University Press 1987 pp. 57–62</ref>

[[Robert Forester Mushet]] found that by adding [[tungsten]] to steel it could produce a very hard edge that would resist losing its hardness at high temperatures. "R. Mushet's special steel" (RMS) became the first [[high-speed steel]].<ref>''Sheffield Steel and America: A Century of Commercial and Technological Independence'' By Geoffrey Tweedale – Cambridge University Press 1987 pp. 66–68</ref> Mushet's steel was quickly replaced by [[tungsten carbide]] steel, developed by Taylor and White in 1900, in which they doubled the tungsten content and added small amounts of chromium and vanadium, producing a superior steel for use in lathes and machining tools. In 1903, the [[Wright brothers]] used a chromium-nickel steel to make the crankshaft for their airplane engine, while in 1908 [[Henry Ford]] began using vanadium steels for parts like crankshafts and valves in his [[Model T Ford]], due to their higher strength and resistance to high temperatures.<ref name="asmchandler">''Metallurgy for the Non-Metallurgist'' by Harry Chandler – ASM International 1998 Page 3–5</ref> In 1912, the Krupp Ironworks in Germany developed a rust-resistant steel by adding 21% chromium and 7% nickel, producing the first stainless steel.<ref>''Sheffield Steel and America: A Century of Commercial and Technological Independence'' By Geoffrey Tweedale – Cambridge University Press 1987 p. 75</ref>

=== Others ===

Due to their high reactivity, most metals were not discovered until the 19th century. A method for extracting aluminium from [[bauxite]] was proposed by [[Humphry Davy]] in 1807, using an [[electric arc]]. Although his attempts were unsuccessful, by 1855 the first sales of pure aluminium reached the market. However, as [[extractive metallurgy]] was still in its infancy, most aluminium extraction-processes produced unintended alloys contaminated with other elements found in the ore; the most abundant of which was copper. These aluminium-copper alloys (at the time termed "aluminium bronze") preceded pure aluminium, offering greater strength and hardness over the soft, pure metal, and to a slight degree were found to be heat treatable.<ref>''Aluminium: Its History, Occurrence, Properties, Metallurgy and Applications'' by Joseph William Richards – Henry Cairy Baird & Co 1887 Page 25–42</ref> However, due to their softness and limited hardenability these alloys found little practical use, and were more of a novelty, until the [[Wright brothers]] used an aluminium alloy to construct the first airplane engine in 1903.<ref name="asmchandler" /> During the time between 1865 and 1910, processes for extracting many other metals were discovered, such as chromium, vanadium, tungsten, [[iridium]], [[cobalt]], and molybdenum, and various alloys were developed.<ref>''Metallurgy: 1863–1963'' by W.H. Dennis – Routledge 2017</ref>

Prior to 1910, research mainly consisted of private individuals tinkering in their own laboratories. However, as the aircraft and automotive industries began growing, research into alloys became an industrial effort in the years following 1910, as new [[magnesium alloy]]s were developed for pistons and [[alloy wheel|wheels]] in cars, and [[pot metal]] for levers and knobs, and aluminium alloys developed for [[airframe]]s and [[aircraft skin]]s were put into use.<ref name="asmchandler" /> The Doehler Die Casting Co. of Toledo, Ohio were known for the production of ''Brastil'', a high tensile corrosion resistant bronze alloy.<ref>{{Cite web |title=Doehler-Jarvis Company Collection, MSS-202 |url=https://www.utoledo.edu/library/canaday/HTML_findingaids/MSS-202.html |access-date=2024-08-16 |website=www.utoledo.edu}}</ref><ref>Woldman’s Engineering Alloys, 9th Edition 1936, American Society for Metals, {{ISBN|978-0-87170-691-1}}</ref>