"with pig iron. These methods of steel production were rendered obsolete by the Linz-Donawitz process of basic oxygen steelmaking (BOS), developed in the 1950s, 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. 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),"
"ingots. The modern era in steelmaking began with the introduction of Henry Bessemer's Bessemer 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 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)"
"craft process of steelmaking was the crucible process. In the 1850s and 1860s, the Bessemer process and the Siemens-Martin process turned steelmaking into a heavy industry. Today there are two major commercial processes for making steel, namely basic oxygen steelmaking, which has liquid pig-iron from the blast furnace and scrap steel as the main feed materials, and electric arc furnace (EAF) steelmaking, which uses scrap steel or direct reduced iron (DRI) as the main feed materials. Oxygen steelmaking is fuelled predominantly by the exothermic nature of the reactions inside the vessel where as in EAF steelmaking, electrical energy is used"
"development of large-scale methods of producing forgeable metal (bar iron or steel). The puddling furnace was initially a means of producing wrought iron, but was later applied to steel production. The real revolution in modern steelmaking only began at the end of the 1850s when the Bessemer process became the first successful method of steelmaking in quantity, followed by the open-hearth furnace. Modern steelmaking processes can be divided into two categories: Primary and Secondary steelmaking. Primary steelmaking involves converting liquid iron from a blast furnace and steel scrap into steel via basic oxygen steelmaking, or melting scrap steel or direct"
"accounted for 60% of global steel output. Modern furnaces will take a charge of iron of up to 400 tons and convert it into steel in less than 40 minutes, compared to 10–12 hours in an open hearth furnace. The basic oxygen process developed outside of traditional ""big steel"" environment. It was developed and refined by a single man, Swiss engineer Robert Durrer, and commercialized by two small steel companies in allied-occupied Austria, which had not yet recovered from the destruction of World War II. In 1856, Henry Bessemer patented a steelmaking process involving oxygen blowing for decarbonizing molten iron"
"to melt the solid scrap and/or DRI materials. In recent times, EAF steelmaking technology has evolved closer to oxygen steelmaking as more chemical energy is introduced into the process. Steelmaking has played a crucial role in the development of ancient, medieval, and modern technological societies. Early processes of steel making were made during the classical era in Ancient Iran, Ancient China, India, and Rome, but the process of ancient steelmaking was lost in the West due to the fall of the Western Roman Empire in the 5th century CE. Cast iron is a hard brittle material that is difficult to"
"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 is continuously cast into long slabs, cut and shaped into bars and extrusions and heat treated to produce a final product. Today only a small fraction is cast into ingots. Approximately 96% of steel"
"Steelmaking Steelmaking is the process for producing steel from iron ore and scrap. In steelmaking, impurities such as nitrogen, silicon, phosphorus, sulfur and excess carbon are removed from the raw iron, and alloying elements such as manganese, nickel, chromium and vanadium are added to produce different grades of steel. Limiting dissolved gases such as nitrogen and oxygen, and entrained impurities (termed ""inclusions"") in the steel is also important to ensure the quality of the products cast from the liquid steel. Steelmaking has existed for millennia, but it was not commercialized on a massive scale until the 19th century. The ancient"
"History of the steel industry (1850–1970) The history of the modern steel industry began in the late 1850s, but since then, steel has been basic to the world's industrial economy. This article is intended only to address the business, economic and social dimensions of the industry, since the bulk production of steel began as a result of Henry Bessemer's development of the Bessemer converter in 1857. Previously steel was very expensive to produce and only used in small expensive items such as knives, swords and armour. Steel is an alloy composed of between 0.2% and 2.0% carbon, and the balance"
"steelmaking process. Without the necessity for this preparatory step the HIsarna process is more energy-efficient and has a lower carbon footprint than traditional steelmaking processes. Steelmaking Steelmaking is the process for producing steel from iron ore and scrap. In steelmaking, impurities such as nitrogen, silicon, phosphorus, sulfur and excess carbon are removed from the raw iron, and alloying elements such as manganese, nickel, chromium and vanadium are added to produce different grades of steel. Limiting dissolved gases such as nitrogen and oxygen, and entrained impurities (termed ""inclusions"") in the steel is also important to ensure the quality of the products"
"work, whereas steel is malleable, relatively easily formed and a versatile material. For much of human history, steel has only been made in small quantities. Since the invention of the Bessemer process in the 19th century and subsequent technological developments in injection technology and process control, mass production of steel has become an integral part of the global economy and a key indicator of modern technological development. The earliest means of producing steel was in a bloomery. Early modern methods of producing steel were often labour-intensive and highly skilled arts. See: An important aspect of the Industrial Revolution was the"
"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 decarbonization via repeated forging under a cold blast. 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. Originally employing charcoal, modern methods use coke, which has proven more economical. In these processes pig iron was refined (fined) in a finery forge to produce"
"of air is replaced with blowing oxygen. It reduced capital cost of the plants, time of smelting, and increased labor productivity. Between 1920 and 2000, labour requirements in the industry decreased by a factor of 1,000, from more than 3 worker-hours per tonne to just 0.003. The vast majority of steel manufactured in the world is produced using the basic oxygen furnace; in 2011, it accounted for 70% of global steel output. Modern furnaces will take a charge of iron of up to 350 tons and convert it into steel in less than 40 minutes, compared to 10–12 hours in"
"develop a modern steel industry by building new steel plants and recycling scrap metal from the United States and Europe. As of 2013 China produced 779 million metric tons of steel each year, making it by far the largest steel producing country in the world. This is compared to 165 for the European Union, 110 for Japan, 87 for the United States and 81 for India. China's 2013 steel production was equivalent to an average of 3.14 cubic meters of steel per second. History of the steel industry (1850–1970) The history of the modern steel industry began in the late"
"now produces the majority of steel in the US. In 2017, there were 9 operating integrated steel mills in the United States (plus one idled), down from 13 in 2000. Integrated mills produced 31% of the steel produced in the US. In an integrated steel mill, iron ore is reduced to metallic iron. In the US, this is done in blast furnaces. The direct-reduction method of producing iron from ore has not been used in the US since 2012. Some of the iron from the blast furnaces is converted to steel; today this is done in basic oxygen furnaces. Iron"
"slag content made the iron very tough, gave it considerable resistance to rusting, and allowed it to be more easily ""forge welded,"" a process in which the blacksmith permanently joins two pieces of iron, or a piece of iron and a piece of steel, by heating them nearly to a white heat and hammering them together. Forge welding is more difficult with modern mild steel, because it welds in a narrower temperature band. The fibrous nature of wrought iron required knowledge and skill to properly form any tool which would be subject to stress. Modern steel is produced using either"
"from below), reducing the amount of nitrogen uptake into the steel. The basic oxygen process is used in all modern steelworks; the last Bessemer converter in the U.S. was retired in 1968. Furthermore, the last three decades have seen a massive increase in the mini-mill business, where scrap steel only is melted with an electric arc furnace. These mills only produced bar products at first, but have since expanded into flat and heavy products, once the exclusive domain of the integrated steelworks. Until these 19th-century developments, steel was an expensive commodity and only used for a limited number of purposes"
"source of low-background steel is ships that were constructed before the Trinity test, most famously the scuttled German World War I battleships in Scapa Flow. From 1856 until the mid 20th century, steel was produced in the Bessemer process where air was forced into Bessemer converters converting the pig iron into steel. By the mid-20th century, many steelworks had switched to the BOS process which uses pure oxygen instead of air. However as both processes use atmospheric gas, they are susceptible to contamination from airborne particulates. Present-day air carries radionuclides, such as cobalt-60, which are deposited into the steel giving"
"tapped from the blast furnace and either cast into pig iron or directed to other vessels for further steel making operations. Historically the Bessemer process was a major advancement in the production of economical steel, but it has now been entirely replaced by other processes such as the basic oxygen furnace. Molten steel is cast into large blocks called ""blooms"". During the casting process various methods are used, such as addition of aluminum, so that impurities in the steel float to the surface where they can be cut off the finished bloom. Because of the energy cost and structural stress"
"the Industrial Revolution, new methods of producing bar iron by substituting coke for charcoal were devised and these were later applied to produce steel, creating a new era of greatly increased use of iron and steel that some contemporaries described as a new Iron Age. In the late 1850s, Henry Bessemer invented a new steelmaking process, that involved blowing air through molten pig iron to burn off carbon, and so to produce mild steel. This and other 19th-century and later steel making processes have displaced wrought iron. Today, wrought iron is no longer produced on a commercial scale, having been"
"was produced in oxygen converters. In the last quarter of the 20th century use of basic oxygen converters for steel production was gradually partially replaced by the electric arc furnace using scrap steel/iron. In Japan the share of LD process decreased from 80% in 1970 to 70% in 2000; worldwide share of the basic oxygen process stabilized at 60%. Basic oxygen steelmaking is a primary steelmaking process for converting the molten pig iron into steel by blowing oxygen through a lance over the molten pig iron inside the converter. Exothermic heat is generated by the oxidation reactions during blowing. The"
"better methods, utilizing an electric arc, were developed in the early 20th century. In another method, developed in the United States in the 1880s, iron and carbon were melted together directly to produce crucible steel. Throughout the 19th century and into the 1920s a large amount of crucible steel was directed into the production of cutting tools, where it was called ""tool steel"". The crucible process continued to be used for specialty steels, but is today obsolete. Similar quality steels are now made with an electric arc furnace. Some uses of ""tool steel"" were displaced, first by high speed steel"
"in the 1740s. In the early modern period, brass, an alloy of copper and zinc, was usually produced by a cementation process in which metallic copper was heated with calamine, a zinc ore, to make calamine brass. Cementation process The cementation process is an obsolete technology for making steel by carburization of iron. Unlike modern steelmaking, it increased the amount of carbon in the iron. It was apparently developed before the 17th century. Derwentcote Steel Furnace, built in 1720, is the earliest surviving example of a cementation furnace. Another example in the UK is the cementation furnace in Doncaster Street,"
"as well in later war efforts. The production of iron or steel is a process consisting of two main stages. In the first stage pig iron is produced in a blast furnace. Alternatively, it may be directly reduced. In the second stage, pig iron is converted to wrought iron, steel, or cast iron. For a few limited purposes when it is needed, pure iron is produced in the laboratory in small quantities by reducing the pure oxide or hydroxide with hydrogen, or forming iron pentacarbonyl and heating it to 250 °C so that it decomposes to form pure iron powder."
"and CPM steel-making smelts ore into steel with an electric arc furnace, refines it by removing some carbon, reducing it by removing the sulphur. Further refining may use argon oxygen decarburization, an implementation of powder metallurgy. The conventional process teems (distributes and pours) the steel into ingot molds. The steel slowly solidifies, allowing the elements to segregate into non-uniform patterns at the microscopic level. The CPM process pours molten steel through a small nozzle. High-pressure gas atomizes the liquid stream into a spray which rapidly cools the steel into a uniform powder. The powder then goes into high-pressure containers and"
"the weld. Modern forge-welding is often automated, using computers, machines, and sophisticated hydraulic-presses to produce a variety of products from a number of various alloys. For example, steel pipe is often forge-welded during the manufacturing process. Flat stock is heated and fed through specially-shaped rollers that both form the steel into a tube and simultaneously provide the pressure to weld the edges into a continuous seam. Diffusion bonding is a common method for forge welding titanium alloys in the aerospace industry. In this process the metal is heated while in a press or die. Beyond a specific critical-temperature, which varies"
"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 a steel's final rolling, it is heat treated for strength; however, this is"
"rarely made. Instead, mild steel is produced from a bessemer converter or by other means including smelting reduction processes such as the Corex Process. The ores of base metals are often sulfides. In recent centuries, reverberatory furnaces have been used. These keep the fuel and the charge being smelted separate. Traditionally these were used for carrying out the first step: formation of two liquids, one an oxide slag containing most of the impurity elements, and the other a sulfide matte containing the valuable metal sulfide and some impurities. Such ""reverb"" furnaces are today about 40 m long, 3 m high"
"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 the 17th century, with the production of blister steel and then crucible steel. With the invention of the Bessemer process in the mid-19th century, a new era of mass-produced steel began. This was followed by the Siemens-Martin process and then the Gilchrist-Thomas process that refined the quality of steel. With their introductions, mild steel replaced wrought iron. Further refinements in the process, such as basic"
"modern steelmaking processes negate the need to blend different steels, pattern welded steel is still used by custom knifemakers for the cosmetic effects it produces. Pattern welding developed out of the necessarily complex process of making blades that were both hard and tough from the erratic and unsuitable output from early iron smelting in bloomeries. The bloomery does not generate temperatures high enough to melt iron and steel, but instead reduces the iron oxide ore into particles of pure iron, which then weld into a mass of sponge iron, consisting of lumps of impurities in a matrix of relatively pure"
"Bessemer process resulting in its obsolescence. Basic oxygen steelmaking is essentially an improved version of the Bessemer process (decarburization by blowing oxygen as gas into the heat rather than burning the excess carbon away by adding oxygen carrying substances into the heat). The advantages of pure oxygen blast over air blast was known to Henry Bessemer, but the 19th-century technology was not advanced enough to allow for the production of the large quantities of pure oxygen to make it economically feasible for use. Bessemer process The Bessemer process was the first inexpensive industrial process for the mass production of steel"
"the wrought iron and was still impossible to fully homogenize in the solid state. Huntsman's process was the first to produce a fully homogeneous steel. Unlike previous methods of steel production, the Huntsman process was the first to fully melt the steel, allowing the full diffusion of carbon throughout the liquid. With the use of fluxes it also allowed the removal of most impurities, producing the first steel of modern quality. Due to carbon's high melting point (nearly triple that of steel) and its tendency to oxidize (burn) at high temperatures, it cannot usually be added directly to molten steel."
"oxygen steelmaking (BOS), largely replaced earlier methods by further lowering the cost of production and increasing the quality of the final product. Today, steel is one of the most common manmade materials in the world, with more than 1.6 billion tons produced annually. Modern steel is generally identified by various grades defined by assorted standards organizations. 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 0.002% and 2.14% by weight for plain iron–carbon alloys. These values vary depending on"