82-858: Cleveland-Cliffs Inc. ( CCI , formerly Cliffs Natural Resources ) is an American steel manufacturer based in Cleveland, Ohio . They specialize in the mining , beneficiation , and pelletizing of iron ore , as well as steelmaking, including stamping and tooling . The company was the world's 25th-largest steel producer and the third-largest in the United States in 2022. It is the largest flat-rolled steel producer in North America. Cleveland-Cliffs manages and operates four iron ore mines in Minnesota and two mines in Michigan , one of which,
164-412: A BOS process is manufactured in one-twelfth the time. Today, electric arc furnaces (EAF) are a common method of reprocessing 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 metric ton), and are thus generally only economical when there is a plentiful supply of cheap electricity. The steel industry
246-563: A Canadian steel manufacturer, for $ 2.5 billion in cash and stock. Cleveland-Cliffs has deposited many of its pre-1981 papers in the Historical Collections of the Great Lakes at Bowling Green State University as well as Central Upper Peninsula Archives at Northern Michigan University . Cleveland-Cliffs reported total CO 2 e emissions (direct + indirect) for December 31, 2020, at 32,200 Kt. Steel Steel
328-531: A brittle alloy commonly called pig iron . Alloy steel is steel to which other alloying elements have been intentionally added to modify the characteristics of steel. Common alloying elements include: manganese , nickel , chromium , molybdenum , boron , titanium , vanadium , tungsten , cobalt , and niobium . Additional elements, most frequently considered undesirable, are also important in steel: phosphorus , sulphur , silicon , and traces of oxygen , nitrogen , and copper . Plain carbon-iron alloys with
410-713: A carbon-intermediate steel by the 1st century AD. 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 °C. Evidence of the earliest production of high carbon steel in South Asia is found in Kodumanal in Tamil Nadu ,
492-444: A change of volume. In this case, expansion occurs. Internal stresses from this expansion generally take the form of compression on the crystals of martensite and tension on the remaining ferrite, with a fair amount of shear on both constituents. If quenching is done improperly, the internal stresses can cause a part to shatter as it cools. At the very least, they cause internal work hardening and other microscopic imperfections. It
574-625: A coal mine in Princeton, West Virginia . The company operates many fully-integrated steel mills and finishing facilities in Kentucky , Indiana , Illinois , Ohio , Michigan , Pennsylvania , West Virginia , and North Carolina . It has annual production capacity of approximately 23 million net tons of raw steel. The firm's earliest predecessor was the Cleveland Iron Mining Company , founded in 1847 and chartered as
656-703: A company by Michigan in 1850. Samuel Mather and six Ohio-based associates had learned of rich iron-ore deposits recently discovered in the highlands of the Upper Peninsula of Michigan . Soon afterwards, the first Soo Locks opened in 1855, allowing iron ore to be shipped from Lake Superior to Lake Erie . Technological improvements, such as the Bessemer process , made it possible for the North American Great Lakes to produce steel on an industrial scale. The south shore of Lake Erie
738-428: A ferrite BCC crystal form, but at higher carbon content it takes a body-centred tetragonal (BCT) structure. There is no thermal activation energy for the transformation from austenite to martensite. There is no compositional change so the atoms generally retain their same neighbours. Martensite has a lower density (it expands during the cooling) than does austenite, so that the transformation between them results in
820-583: A hard oxide forms on the metal surface; this is known as stainless steel . Tungsten slows the formation of cementite , keeping carbon in the iron matrix and allowing martensite to preferentially form at slower quench rates, resulting in high-speed steel . The addition of lead and sulphur decrease grain size, thereby making the steel easier to turn , but also more brittle and prone to corrosion. Such alloys are nevertheless frequently used for components such as nuts, bolts, and washers in applications where toughness and corrosion resistance are not paramount. For
902-445: A hard but brittle martensitic structure. The steel is then tempered, which is just a specialized type of annealing, to reduce brittleness. In this application the annealing (tempering) process transforms some of the martensite into cementite, or spheroidite and hence it reduces the internal stresses and defects. The result is a more ductile and fracture-resistant steel. When iron is smelted from its ore, it contains more carbon than
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#1732780977293984-434: A higher than 2.1% carbon content are known as cast iron . With modern steelmaking techniques such as powder metal forming, it is possible to make very high-carbon (and other alloy material) steels, but such are not common. Cast iron is not malleable even when hot, but it can be formed by casting as it has a lower melting point than steel and good castability properties. Certain compositions of cast iron, while retaining
1066-412: A narrow range of concentrations of mixtures of carbon and iron that make steel, several different metallurgical structures, with very different properties can form. Understanding such properties is essential to making quality steel. At room temperature , the most stable form of pure iron is the body-centred cubic (BCC) structure called alpha iron or α-iron. It is a fairly soft metal that can dissolve only
1148-545: A proposal to U.S. Steel CEO David Burnett, to acquire the company for a total enterprise value of $ 10 billion, in a cash and stock deal. The proposal has been endorsed by the United Steelworkers , but was rejected by US Steel on August 13. Ultimately, Cleveland-Cliffs failed to purchase U.S. Steel as the company agreed to be acquired by Japan's Nippon Steel instead for $ 14.9 billion. On July 15, 2024, Cleveland-Cliffs announced that it would acquire Stelco ,
1230-443: A sharp increase in the cost of diesel fuel. During the 1970s, Cleveland-Cliffs had large interests in uranium and shale oil fields, as well as the oil and gas drilling industries. It also had holdings in the forest products industry. This interests were sold in the 1980s when the company refocused its efforts on its core iron ore business. After the recessions of 1974–1975 and 1981–1983, Cleveland-Cliffs shrank its operations, closing
1312-534: A small concentration of carbon, no more than 0.005% at 0 °C (32 °F) and 0.021 wt% at 723 °C (1,333 °F). The inclusion of carbon in alpha iron is called ferrite . At 910 °C, pure iron transforms into a face-centred cubic (FCC) structure, called gamma iron or γ-iron. The inclusion of carbon in gamma iron is called austenite. The more open FCC structure of austenite can dissolve considerably more carbon, as much as 2.1%, (38 times that of ferrite) carbon at 1,148 °C (2,098 °F), which reflects
1394-453: A steel's final rolling, it is heat treated for strength; however, this is relatively rare. Steel was known in antiquity and was produced in bloomeries and crucibles . The earliest known production of steel is seen in pieces of ironware excavated from an archaeological site in Anatolia ( Kaman-Kalehöyük ) which are nearly 4,000 years old, dating from 1800 BC. Wootz steel
1476-477: A subsequent step. Other materials are often added to the iron/carbon mixture to produce steel with the desired properties. Nickel and manganese in steel add to its tensile strength and make the austenite form of the iron-carbon solution more stable, chromium increases hardness and melting temperature, and vanadium also increases hardness while making it less prone to metal fatigue . To inhibit corrosion, at least 11% chromium can be added to steel so that
1558-672: Is continuously cast into long slabs, cut and shaped into bars and extrusions and heat treated to produce a final product. Today, approximately 96% of steel is continuously cast, while only 4% is produced as ingots. The ingots are then heated in a soaking pit and hot rolled into slabs, billets , or blooms . Slabs are hot or cold rolled into sheet metal or plates. Billets are hot or cold rolled into bars, rods, and wire. Blooms are hot or cold rolled into structural steel , such as I-beams and rails . In modern steel mills these processes often occur in one assembly line , with ore coming in and finished steel products coming out. Sometimes after
1640-411: Is a surviving example of this ship type. For almost a century, the black-hulled Cleveland-Cliffs ships were familiar sights on the upper lakes. Demand for American iron ore hit peaks during World War I , World War II , and the post-World War II consumer boom. In 1933, Edward Greene (the son-in-law of Jeptha Homer Wade II) replaced William G. Mather as the head of the company. The Mather A Mine opened in
1722-636: Is also very reusable: it is one of the world's most-recycled materials, with a recycling rate of over 60% globally . The noun steel originates from the Proto-Germanic adjective * * stahliją or * * stakhlijan 'made of steel', which is related to * * stahlaz or * * stahliją 'standing firm'. The carbon content of steel is between 0.02% and 2.14% by weight for plain carbon steel ( iron - carbon alloys ). Too little carbon content leaves (pure) iron quite soft, ductile, and weak. Carbon contents higher than those of steel make
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#17327809772931804-416: Is always the main element in steel, but many other elements may be present or added. Stainless steels , which are resistant to corrosion and oxidation , typically need an additional 11% chromium . Iron is the base metal of steel. Depending on the temperature, it can take two crystalline forms (allotropic forms): body-centred cubic and face-centred cubic . The interaction of the allotropes of iron with
1886-432: Is an alloy of iron and carbon with improved strength and fracture resistance compared to other forms of iron. Because of its high tensile strength and low cost, steel is one of the most commonly manufactured materials in the world. Steel is used in buildings, as concrete reinforcing rods, in bridges, infrastructure, tools, ships, trains, cars, bicycles, machines, electrical appliances, furniture, and weapons. Iron
1968-403: Is common for quench cracks to form when steel is water quenched, although they may not always be visible. There are many types of heat treating processes available to steel. The most common are annealing , quenching , and tempering . Annealing is the process of heating the steel to a sufficiently high temperature to relieve local internal stresses. It does not create a general softening of
2050-403: Is desirable. To become steel, it must be reprocessed to reduce the carbon to the correct amount, at which point other elements can be added. In the past, steel facilities would cast the raw steel product into ingots which would be stored until use in further refinement processes that resulted in the finished product. In modern facilities, the initial product is close to the final composition and
2132-405: Is extracted from iron ore by removing the oxygen through its combination with a preferred chemical partner such as carbon which is then lost to the atmosphere as carbon dioxide. This process, known as smelting , was first applied to metals with lower melting points, such as tin , which melts at about 250 °C (482 °F), and copper , which melts at about 1,100 °C (2,010 °F), and
2214-408: Is heat treated to contain both a ferritic and martensitic microstructure to produce a formable, high strength steel. 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
2296-691: Is often considered an indicator of economic progress, because of the critical role played by steel in infrastructural and overall economic development . In 1980, there were more than 500,000 U.S. steelworkers. By 2000, the number of steelworkers had fallen to 224,000. The economic boom in China and India caused a massive increase in the demand for steel. Between 2000 and 2005, world steel demand increased by 6%. Since 2000, several Indian and Chinese steel firms have expanded to meet demand, such as Tata Steel (which bought Corus Group in 2007), Baosteel Group and Shagang Group . As of 2017 , though, ArcelorMittal
2378-488: Is one of the world's most-recycled materials, with a recycling rate of over 60% globally; in the United States alone, over 82,000,000 metric tons (81,000,000 long tons; 90,000,000 short tons) were recycled in the year 2008, for an overall recycling rate of 83%. As more steel is produced than is scrapped, the amount of recycled raw materials is about 40% of the total of steel produced - in 2016, 1,628,000,000 tonnes (1.602 × 10 long tons; 1.795 × 10 short tons) of crude steel
2460-547: Is the world's largest steel producer . In 2005, the British Geological Survey stated China was the top steel producer with about one-third of the world share; Japan , Russia , and the United States were second, third, and fourth, respectively, according to the survey. The large production capacity of steel results also in a significant amount of carbon dioxide emissions inherent related to
2542-655: The Golconda area in Andhra Pradesh and Karnataka , regions of India , as well as in Samanalawewa and Dehigaha Alakanda, regions of Sri Lanka . This came to be known as wootz steel , produced in South India by about the sixth century BC and exported globally. The steel technology existed prior to 326 BC in the region as they are mentioned in literature of Sangam Tamil , Arabic, and Latin as
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2624-511: The board of directors . Lourenco Goncalves was appointed chairman, president and CEO of the company. The reconstituted Board moved to shift the company's strategic objectives from global diversification to a renewed focus on strengthening its U.S. iron ore business. In December 2015, the company sold its remaining North American coal operations. Cliffs announced plans in early 2016 to close the Empire Mine near Marquette, Michigan, terminating
2706-599: 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 at Coalbrookdale during the 1610s. The raw material for this process were bars of iron. During
2788-419: The hardness , quenching behaviour , need for annealing , tempering behaviour , yield strength , and tensile strength of the resulting steel. The increase in steel's strength compared to pure iron is possible only by reducing iron's ductility. Steel was produced in bloomery furnaces for thousands of years, but its large-scale, industrial use began only after more efficient production methods were devised in
2870-445: 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. Crucible steel is steel that has been melted in a crucible rather than having been forged , with the result that it is more homogeneous. Most previous furnaces could not reach high enough temperatures to melt
2952-475: The 17th century, the first step in European steel production has been the smelting of iron ore into pig iron in a blast furnace . Originally employing charcoal, modern methods use coke , which has proven more economical. 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. The production of steel by
3034-626: The 17th century, with the introduction of the blast furnace and production of crucible steel . This was followed by the Bessemer process in England in the mid-19th century, and then by the open-hearth furnace . With the invention of the Bessemer process, a new era of mass-produced steel began. Mild steel replaced wrought iron . The German states were the major steel producers in Europe in
3116-481: The 19th century. American steel production was centred in Pittsburgh , Bethlehem, Pennsylvania , and Cleveland until the late 20th century. Currently, world steel production is centered in China, which produced 54% of the world's steel in 2023. Further refinements in the process, such as basic oxygen steelmaking (BOS), largely replaced earlier methods by further lowering the cost of production and increasing
3198-608: The Arabs from Persia, who took it from India. It was originally created from several different materials including various trace elements , apparently ultimately from the writings of Zosimos of Panopolis . In 327 BC, Alexander the Great was rewarded by the defeated King Porus , not with gold or silver but with 30 pounds of steel. A recent study has speculated that carbon nanotubes were included in its structure, which might explain some of its legendary qualities, though, given
3280-644: The Black Thor and Black Label, and 47% ownership of the Big Daddy chromite deposits in the Ring of Fire district in the James Bay Lowlands of Ontario, Canada. In July 2010, Cliffs increased its ownership stake in Big Daddy by acquiring Spider Resources for C$ 125 million. In 2015, these assets were sold to rival Noront Resources, owner of a minority stake in Big Daddy, for US$ 20 million. In May 2011,
3362-520: The Empire Mine was idled for six months. President George W. Bush enacted the 2002 United States steel tariff that greatly benefitted domestically-produced steel. Benefitting from the tariff, the company embarked upon a strategy to expand globally and to diversify into other minerals, leading to the acquisitions of iron-ore properties in Brazil, Canada and Australia and coal properties in Australia and
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3444-629: The Empire Mine, has been indefinitely idled. These mines produce various grades of iron ore pellets, including standard and fluxed, for use in blast furnaces as part of the steelmaking process as well as Direct Reduced (DR) grade pellets for use in Direct Reduced Iron (DRI) applications. Since the mines are located near the Great Lakes , the majority of the pellets are transported by rail to loading ports for shipments via vessel to steelmakers in North America. During 2020, 2019 and 2018,
3526-465: The Great Lakes shipping industry. In 1994, the company acquired Northshore Mining in Silver Bay, Minnesota . In early 2001, Cleveland-Cliffs managed LTV Steel Mining Company permanently closed in the wake of Ling-Temco-Vought 's bankruptcy. Later that year, the company cut its dividend by 73% due to low prices. In 2002, Ling-Temco-Vought , a partner in the Empire Mine managed by CCI, closed and
3608-791: The Humboldt Mine in 1960. The Republic Mine was converted from a shaft mine to an open pit and concentrator in 1956 and a two-kiln pellet plant was added in 1962. The Empire Mine opened in 1963 and was expanded in the mid- and late-1970s; the Pioneer Pellet Plant was opened in 1965 to pelletize the underground ore from the Mather B Mine in Negaunee, Michigan . In 1974, the Tilden Mine opened in Ishpeming, Michigan . This mine
3690-470: The Linz-Donawitz process of basic oxygen steelmaking (BOS), developed in 1952, 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, and because, with respect to the open hearth process, the same quantity of steel from
3772-543: The Mather B Mine and the Pioneer Pellet Plant and associated Ore Improvement Plant in 1979. The Humboldt Pellet Plant closed in 1981 and the Republic Mine was idled in 1981 and closed for good in 1996, when Cliffs began turning the associated tailings ponds into compensatory wetlands for its other properties. Over half of the Marquette Iron Range employees were laid off and, in 1984, Cliffs withdrew from
3854-539: The US. In 2003, the company, in a joint venture with Laiwu Steel , purchased the assets of bankrupt Eveleth Mines and formed United Taconite LLC. In 2008, it acquired the full ownership for $ 100 million in cash and 1,529,619 common shares. In June 2007, the company acquired PinnOak, its first domestic coal company, which mined coal in Alabama and West Virginia and once belonged to U.S. Steel . Due to its venture into coal,
3936-401: The alloying elements, primarily carbon, gives steel and cast iron their range of unique properties. In pure iron, the crystal structure has relatively little resistance to the iron atoms slipping past one another, and so pure iron is quite ductile , or soft and easily formed. In steel, small amounts of carbon, other elements, and inclusions within the iron act as hardening agents that prevent
4018-436: The austenite grain boundaries until the percentage of carbon in the grains has decreased to the eutectoid composition (0.8% carbon), at which point the pearlite structure forms. For steels that have less than 0.8% carbon (hypoeutectoid), ferrite will first form within the grains until the remaining composition rises to 0.8% of carbon, at which point the pearlite structure will form. No large inclusions of cementite will form at
4100-471: The austenite is for it to precipitate out of solution as cementite , leaving behind a surrounding phase of BCC iron called ferrite with a small percentage of carbon in solution. The two, cementite and ferrite, precipitate simultaneously producing a layered structure called pearlite , named for its resemblance to mother of pearl . In a hypereutectoid composition (greater than 0.8% carbon), the carbon will first precipitate out as large inclusions of cementite at
4182-430: The board from 1890 to 1947, participating in the transition from the hard-rock iron ore of Upper Michigan to the soft hematite of Minnesota's Mesabi Range and adjacent lodes. Under Mather, Cleveland-Cliffs was a leader in the development of the classic-type lake freighter , a bulk-cargo vessel especially designed to carry Great Lakes commodities. The 618-foot-long (188 m) SS. William G. Mather , launched in 1925,
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#17327809772934264-494: The boundaries in hypoeutectoid steel. The above assumes that the cooling process is very slow, allowing enough time for the carbon to migrate. As the rate of cooling is increased the carbon will have less time to migrate to form carbide at the grain boundaries but will have increasingly large amounts of pearlite of a finer and finer structure within the grains; hence the carbide is more widely dispersed and acts to prevent slip of defects within those grains, resulting in hardening of
4346-455: The combination, bronze, which has a melting point lower than 1,083 °C (1,981 °F). In comparison, cast iron melts at about 1,375 °C (2,507 °F). Small quantities of iron were smelted in ancient times, in the solid-state, by heating the ore in a charcoal fire and then welding the clumps together with a hammer and in the process squeezing out the impurities. With care, the carbon content could be controlled by moving it around in
4428-561: The combined firm to change its name to the Cleveland-Cliffs Iron Company. The company invested substantially to improve the logistics of iron-ore transport. In 1892, the firm built the Lake Superior and Ishpeming Railroad to carry iron ore from the mines directly to company-owned docks on Lake Superior . William G. Mather , the son of Samuel, guided Cleveland-Cliffs as president and later as chairman of
4510-575: The company acquired Consolidated Thompson Iron Mines from Wuhan Iron and Steel Corporation for C$ 4.9 billion. The acquisition included Bloom Lake iron ore mine in Quebec . On May 5, 2011, the company was added to the Fortune 500 . Its ranking of 477 was based on the company's performance in 2010. in July 2013, CEO Joseph Carrabba announced that he would retire by December 31, 2013. Lead director James Kirsch
4592-514: The company changed its name from Cleveland-Cliffs to Cliffs Natural Resources in October 2008. In 2008, the company agreed to acquire Alpha Natural Resources but called off the transaction in November 2008 due to the financial crisis of 2007–2008 . It paid a $ 70 million breakup fee . In January 2010, the company acquired Freewest Resources Canada for C$ 240 million, giving it 100% ownership of
4674-670: The company sold 12 million, 19 million and 21 million long tons of iron ore product, respectively, to third parties. The company operates a Hot-Briquetted Iron (HBI) facility in Toledo, Ohio . HBI is a form of DRI that can be used as an alternative to scrap iron. When used as a feedstock, HBI can enable an electric arc furnace to produce more valuable grades of steel. It also operates three coke -making facilities in Burns Harbor, Indiana , Monessen, Pennsylvania , and Warren, Ohio , with an annual capacity of 2.6 million tons, as well as
4756-536: The early 1940s and the Mather B shaft in the 1950s. As the Cold War continued, reserves of mineable hematite dwindled in northern Minnesota and Cleveland-Cliffs returned some of its focus to its traditional areas of interest around the Marquette Iron Range , where new deposits of magnetite were opened. The first pellet plant was built at Eagle Mills in 1954, followed by the first grate/kiln plant at
4838-452: The economies of melting and casting, can be heat treated after casting to make malleable iron or ductile iron objects. Steel is distinguishable from wrought iron (now largely obsolete), which may contain a small amount of carbon but large amounts of slag . Iron is commonly found in the Earth's crust in the form of an ore , usually an iron oxide, such as magnetite or hematite . Iron
4920-648: The finest steel in the world exported to the Roman, Egyptian, Chinese and Arab worlds at that time – what they called Seric Iron . A 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 period . The Chinese and locals in Anuradhapura , Sri Lanka had also adopted
5002-579: The fire. Unlike copper and tin, liquid or solid iron dissolves carbon quite readily. All of these temperatures could be reached with ancient methods used since the Bronze Age . Since the oxidation rate of iron increases rapidly beyond 800 °C (1,470 °F), it is important that smelting take place in a low-oxygen environment. Smelting, using carbon to reduce iron oxides, results in an alloy ( pig iron ) that retains too much carbon to be called steel. The excess carbon and other impurities are removed in
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#17327809772935084-513: The form of charcoal) in a crucible, was produced in Merv by the 9th to 10th century AD. In the 11th century, there is evidence of the production of steel in 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 . Since
5166-599: The hardenability of thick sections. 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. 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
5248-461: The jobs of approximately 400 workers. The company announced on August 15, 2017, that it was returning to its former brand name, Cleveland-Cliffs Inc. In August 2018, the company sold its Asia Pacific iron ore assets. It also sold its Australian assets. On March 13, 2020, the company acquired AK Steel Holding for $ 1.1 billion. In December 2020, the company acquired the United States operations of ArcelorMittal for approximately $ 1.4 billion, making it
5330-535: The largest producer of flat-rolled steel and iron ore pellets in North America. In February 2022, Cleveland-Cliffs agreed to pay a $ 3 million settlement related to Clean Water Act violations, including a cyanide and ammonia spill in August 2019 that killed thousands of fish and closed Lake Michigan beaches. After the settlement, Cleveland-Cliffs stated it would change its water testing and public announcement procedures. On July 28, 2023, Cleveland-Cliffs executives sent
5412-439: The main production route. At the end of 2008, the steel industry faced a sharp downturn that led to many cut-backs. In 2021, it was estimated that around 7% of the global greenhouse gas emissions resulted from the steel industry. Reduction of these emissions are expected to come from a shift in the main production route using cokes, more recycling of steel and the application of carbon capture and storage technology. Steel
5494-450: The most part, however, p-block elements such as sulphur, nitrogen , phosphorus , and lead are considered contaminants that make steel more brittle and are therefore removed from steel during the melting processing. The density of steel varies based on the alloying constituents but usually ranges between 7,750 and 8,050 kg/m (484 and 503 lb/cu ft), or 7.75 and 8.05 g/cm (4.48 and 4.65 oz/cu in). Even in
5576-446: The movement of dislocations . The carbon in typical steel alloys may contribute up to 2.14% of its weight. Varying the amount of carbon and many other alloying elements, as well as controlling their chemical and physical makeup in the final steel (either as solute elements, or as precipitated phases), impedes the movement of the dislocations that make pure iron ductile, and thus controls and enhances its qualities. These qualities include
5658-449: The product but only locally relieves strains and stresses locked up within the material. Annealing goes through three phases: recovery , recrystallization , and grain growth . The temperature required to anneal a particular steel depends on the type of annealing to be achieved and the alloying constituents. Quenching involves heating the steel to create the austenite phase then quenching it in water or oil . This rapid cooling results in
5740-759: The production methods of creating wootz steel from the Chera Dynasty Tamils of South India by the 5th century AD. In Sri Lanka, this early steel-making method employed a unique wind furnace, driven by the monsoon winds, capable of producing high-carbon steel. Since the technology was acquired from the Tamilians from South India, the origin of steel technology in India can be conservatively estimated at 400–500 BC. The manufacture of wootz steel and Damascus steel , famous for its durability and ability to hold an edge, may have been taken by
5822-426: The quality of the final product. Today more than 1.6 billion tons of steel is produced annually. Modern steel is generally identified by various grades defined by assorted standards organizations . The modern steel industry is one of the largest manufacturing industries in the world, but also one of the most energy and greenhouse gas emission intense industries, contributing 8% of global emissions. However, steel
5904-401: The steel. At the very high cooling rates produced by quenching, the carbon has no time to migrate but is locked within the face-centred austenite and forms martensite . Martensite is a highly strained and stressed, supersaturated form of carbon and iron and is exceedingly hard but brittle. Depending on the carbon content, the martensitic phase takes different forms. Below 0.2% carbon, it takes on
5986-561: 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. The modern era in steelmaking began with the introduction of Henry Bessemer 's process in 1855, the raw material for which was pig iron. His method let him produce steel in large quantities cheaply, thus mild steel came to be used for most purposes for which wrought iron
6068-561: The technology of that time, such qualities were produced by chance rather than by design. 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 tons of soil, a remarkable feat at the time. One such furnace was found in Samanalawewa and archaeologists were able to produce steel as the ancients did. Crucible steel , formed by slowly heating and cooling pure iron and carbon (typically in
6150-525: The upper carbon content of steel, beyond which is cast iron. When carbon moves out of solution with iron, it forms a very hard, but brittle material called cementite (Fe 3 C). When steels with exactly 0.8% carbon (known as a eutectoid steel), are cooled, the austenitic phase (FCC) of the mixture attempts to revert to the ferrite phase (BCC). The carbon no longer fits within the FCC austenite structure, resulting in an excess of carbon. One way for carbon to leave
6232-484: Was and is the only mine in the world with the ability to produce both hematite and magnetite pellets. In 1970, a high-grade iron-ore mine was opened at Pannawonica in the Pilbara region of Western Australia , with a 200 km (120 mi) rail line to processing facilities at Cape Lambert for which the residential township of Wickham was built. A pellet plant was built but ceased operation before 1980, following
6314-718: Was developed in Southern India and Sri Lanka in the 1st millennium BCE. 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 India using crucibles occurred by the sixth century BC, the pioneering precursor to modern steel production and metallurgy. High-carbon steel was produced in Britain at Broxmouth Hillfort from 490–375 BC, and ultrahigh-carbon steel
6396-467: Was elected non-executive chairperson in his stead. Gary Halverson, formerly interim chief operating officer of Barrick Gold , was appointed president and chief operating officer in October 2013, and president and chief executive officer in February 2014. At the 2014 annual general meeting , six new directors nominated by activist hedge fund Casablanca Capital were elected, giving the fund control of
6478-509: Was formerly used. The Gilchrist-Thomas process (or basic Bessemer process ) was an improvement to the Bessemer process, made by lining the converter with a basic material to remove phosphorus. Another 19th-century steelmaking process was the Siemens-Martin process , which complemented the Bessemer process. It consisted of co-melting bar iron (or steel scrap) with pig iron. These methods of steel production were rendered obsolete by
6560-471: Was near a supply of coal , making that region an efficient point for the construction of steel mills. The company's request for government intervention quashed the Upper Peninsula miners' strike of 1865 . In the late 1800s, the company expanded via acquisitions to gain market share . The former Cleveland Iron Mining Co. was a survivor of this shakeout , purchasing many of its competitors. One key merger in 1890, with Jeptha Wade 's Cliffs Iron Company led
6642-438: Was produced globally, with 630,000,000 tonnes (620,000,000 long tons; 690,000,000 short tons) recycled. Modern steels are made with varying combinations of alloy metals to fulfil many purposes. Carbon steel , composed simply of iron and carbon, accounts for 90% of steel production. Low alloy steel is alloyed with other elements, usually molybdenum , manganese, chromium, or nickel, in amounts of up to 10% by weight to improve
6724-757: Was produced in the Netherlands from the 2nd-4th centuries AD. The Roman author Horace identifies steel weapons such as the falcata in the Iberian Peninsula , while Noric steel was used by the Roman military . The Chinese of the Warring States period (403–221 BC) had quench-hardened steel, while Chinese of the Han dynasty (202 BC—AD 220) created steel by melting together wrought iron with cast iron, thus producing
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