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Pig Iron
Pig iron, also known as crude iron, is an intermediate good used by the iron industry in the production of steel. It is developed by smelting iron ore in a blast furnace. Pig iron has a high carbon content, typically 3.8–4.7%, along with silica and other dross, which makes it brittle and not useful directly as a material except for limited applications. Etymology The traditional shape of the molds used for pig iron ingots is a branching structure formed in sand, with many individual ingots at right angles to a central channel or "runner", resembling a litter of piglets being nursed by a sow. When the metal had cooled and hardened, the smaller ingots (the "pigs") were simply broken from the runner (the "sow"), hence the name "pig iron". As pig iron is intended for remelting, the uneven size of the ingots and the inclusion of small amounts of sand are insignificant issues when compared to the ease of casting and handling. History The Chinese were already making pig ir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Casting Pig Iron, Iroquois Smelter, Chicago
Casting is a manufacturing process in which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process. Casting materials are usually metals or various time setting materials that cure after mixing two or more components together; examples are epoxy, concrete, plaster and clay. Casting is most often used for making complex shapes that would be otherwise difficult or uneconomical to make by other methods. Heavy equipment like machine tool beds, ships' propellers, etc. can be cast easily in the required size, rather than fabricating by joining several small pieces. Casting is a 7,000-year-old process. The oldest surviving casting is a copper frog from 3200 BC. History Throughout history, metal casting has been used to make tools, weapons, and religious objects. Metal casting history and developmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decarburization
Decarburization (or decarbonization) is the process of decreasing carbon content, which is the opposite of carburization. The term is typically used in metallurgy, describing the decrease of the content of carbon in metals (usually steel). Decarburization occurs when the metal is heated to temperatures of 700 °C or above when carbon in the metal reacts with gases containing oxygen or hydrogen. The removal of carbon removes hard carbide phases resulting in a softening of the metal, primarily at the surfaces which are in contact with the decarburizing gas. Decarburization can be either advantageous or detrimental, depending on the application for which the metal will be used. It is thus both something that can be done intentionally as a step in a manufacturing process, or something that happens as a side effect of a process (such as rolling) and must be either prevented or later reversed (such as via a carburization step). The decarburization mechanism can be described as th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Transition
In physics, chemistry, and other related fields like biology, a phase transition (or phase change) is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic State of matter, states of matter: solid, liquid, and gas, and in rare cases, plasma (physics), plasma. A phase of a thermodynamic system and the states of matter have uniform physical property, physical properties. During a phase transition of a given medium, certain properties of the medium change as a result of the change of external conditions, such as temperature or pressure. This can be a discontinuous change; for example, a liquid may become gas upon heating to its boiling point, resulting in an abrupt change in volume. The identification of the external conditions at which a transformation occurs defines the phase transition point. Types of phase transition States of matter Phase transitions commonly refer to when a substance tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slag
The general term slag may be a by-product or co-product of smelting (pyrometallurgical) ores and recycled metals depending on the type of material being produced. Slag is mainly a mixture of metal oxides and silicon dioxide. Broadly, it can be classified as ferrous (co-products of processing iron and steel), ferroalloy (a by-product of ferroalloy production) or non-ferrous/ base metals (by-products of recovering non-ferrous materials like copper, nickel, zinc and phosphorus). Within these general categories, slags can be further categorized by their precursor and processing conditions (e.g., blast furnace slags, air-cooled blast furnace slag, granulated blast furnace slag, basic oxygen furnace slag, and electric arc furnace slag). Slag generated from the EAF process can contain toxic metals, which can be hazardous to human and environmental health. Due to the large demand for ferrous, ferralloy, and non-ferrous materials, slag production has increased throughout the years des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prill
A prill is a small aggregate or globule of a material, most often a dry sphere, formed from a melted liquid through spray crystallization. Prilled is a term used in mining and manufacturing to refer to a product that has been pelletized. ANFO explosive typically comprises ammonium nitrate prills mixed with #2 fuel oil. The pellets are a neater, simpler form for handling, with reduced dust. The material to be prilled must be in a solid state at room temperature and a low-viscosity liquid when melted. Prills are formed by allowing drops of the melted prill substance to congeal or freeze in mid-air after being dripped from the top of a tall prilling tower. Certain agrochemicals such as urea are often supplied in prilled form. Fertilizers (ammonium nitrate, urea, NPK fertilizer) and some detergent powders are commonly manufactured as prills.Vasant Gowariker, V. N. Krishnamurthy, Sudha Gowariker, Manik Dhanorkar, Kalyani Paranjape (2009). ''The Fertilizer Encyclopedia''. John Wil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct Reduction
read online, part I, pp. 240; 250-254; 257. (capacity 650,000 t/year).(fr) Adolf Ledebur (trans. Barbary de Langlade revised and annotated by F. Valton), ''Manuel théorique et pratique de la métallurgie du fer, Tome I et Tome II'', t. 2, Librairie polytechnique Baudry et Cie éditeur, 1895 [:fr:Référence:Manuel théorique et pratique de la métallurgie du fer (A.Ledebur), details of editions], pp. 350-352. In the iron and Steel, steel industry, direct reduction is a set of processes for obtaining iron from iron ore, by reducing iron oxides without melting the metal. The resulting product is Direct reduced iron, pre-reduced iron ore. Historically, direct reduction was used to obtain a mix of iron and slag called a bloom in a bloomery. At the beginning of the 20th century, this process was abandoned in favor of the blast furnace, which produces iron in two stages (reduction-melting to produce cast iron, followed by Refining (metallurgy), refining in a Converting (metallurgy), conve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bloomery
A bloomery is a type of metallurgical furnace once used widely for smelting iron from its iron oxides, oxides. The bloomery was the earliest form of smelter capable of smelting iron. Bloomeries produce a porous mass of iron and slag called a ''bloom''. The mix of slag and iron in the bloom, termed ''Direct reduced iron, sponge iron'', is usually consolidated and further forged into wrought iron. Blast furnaces, which produce pig iron, have largely superseded bloomeries. Process A bloomery consists of a wikt:pit, pit or chimney with heat-resistant walls made of earth, clay, or Rock (geology), stone. Near the bottom, one or more pipes (made of clay or metal) enter through the side walls. These pipes, called tuyeres, allow air to enter the furnace, either by natural draught or forced with bellows or a trompe. An opening at the bottom of the bloomery may be used to remove the bloom, or the bloomery can be tipped over and the bloom removed from the top. The first step taken b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wrought Iron
Wrought iron is an iron alloy with a very low carbon content (less than 0.05%) in contrast to that of cast iron (2.1% to 4.5%), or 0.25 for low carbon "mild" steel. Wrought iron is manufactured by heating and melting high carbon cast iron in an open charcoal or coke hearth or furnace in a process known as puddling. The high temperatures cause the excess carbon to oxidise, the iron being stirred or puddled during the process in order to achieve this. As the carbon content reduces, the melting point of the iron increases, ultimately to a level which is higher than can be achieved by the hearth, hence the wrought iron is never fully molten and many impurities remain. The primary advantage of wrought iron over cast iron is its malleability - where cast iron is too brittle to bend or shape without breaking, wrought iron is highly malleable, and much easier to bend. Wrought iron is a semi-fused mass of iron with fibrous slag inclusions (up to 2% by weight), which give it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silk Road
The Silk Road was a network of Asian trade routes active from the second century BCE until the mid-15th century. Spanning over , it played a central role in facilitating economic, cultural, political, and religious interactions between the Eastern world, Eastern and Western worlds. The name "Silk Road" was coined in the late 19th century, but some 20th- and 21st-century historians instead prefer the term Silk Routes, on the grounds that it more accurately describes the intricate web of land and sea routes connecting Central Asia, Central, East Asia, East, South Asia, South, Southeast Asia, Southeast, and West Asia as well as East Africa and Southern Europe. The Silk Road derives its name from the highly lucrative trade of silk textiles that were History of Silk, primarily produced in China. The network began with the expansion of the Han dynasty (202 BCE220 CE) into Central Asia around 114 BCE, through the missions and explorations of the Chinese imperial env ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Westphalia
Westphalia (; ; ) is a region of northwestern Germany and one of the three historic parts of the state of North Rhine-Westphalia. It has an area of and 7.9 million inhabitants. The territory of the region is almost identical with the historic Province of Westphalia, which was a part of the Kingdom of Prussia from 1815 to 1918 and the Free State of Prussia from 1918 to 1946. In 1946, Westphalia merged with North Rhine, another former part of Prussia, to form the newly created state of North Rhine-Westphalia. In 1947, the state with its two historic parts was joined by a third one: Lippe, a former Principality of Lippe, principality and Free State of Lippe, free state. The seventeen Districts of Germany, districts and nine Independent city#Germany, independent cities of Westphalia and Lippe (district), the single district of Lippe are members of the North Rhine-Westphalia#Subdivisions, Westphalia-Lippe Regional Association (''Landschaftsverband Westfalen-Lippe''). Previo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
County Of Mark
The County of Mark (, colloquially known as ) was a county and Imperial State, state of the Holy Roman Empire in the Lower Rhenish–Westphalian Circle. It lay south of Lippe (river), Lippe river on both sides of the Ruhr river along the Volme and Lenne rivers. The Counts de la Mark were among the most powerful and influential Westphalian lords in the Holy Roman Empire. The name ''Mark'' derived from a small village Mark and the nearby Castle Mark, the latter was built between 1190 and 1202, both today incorporated in the unitary authority Hamm, North Rhine-Westphalia, Hamm, founded in 1226 by the first Count, Adolph de la Mark. His father used the older title Altena or Berg-Altena. The name of the county is recalled to the present-day district in lands south of the Ruhr in North Rhine-Westphalia, Germany, in 1975 when the districts were rearranged and the former district Altena was merged with former parts of neighbouring districts. The district Märkischer Kreis is only the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
