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Crucible (Impact)
A crucible is a container in which metals or other substances may be melted or subjected to very high temperatures. Although crucibles have historically tended to be made out of clay, they can be made from any material that withstands temperatures high enough to melt or otherwise alter its contents. History Typology and chronology The form of the crucible has varied through time, with designs reflecting the process for which they are used, as well as regional variation. The earliest crucible forms derive from the sixth/fifth millennium B.C. in Eastern Europe and Iran. Chalcolithic Crucibles used for copper smelting were generally wide shallow vessels made from clay that lacks refractory properties which is similar to the types of clay used in other ceramics of the time. During the Chalcolithic period, crucibles were heated from the top by using blowpipes.Hauptmann A., 2003, ''Developments in copper Metallurgy During the Fourth and Third Millennia B.C. at Feinan'', Jordan, P. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementation Process
The cementation process is an Obsolescence, 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, Sheffield, cementation furnace in Doncaster Street, Sheffield. Origins The process was described in a treatise published in Prague in 1574. It was invented by Johann Nussbaum of Magdeburg, who began operations at Nuremberg (with partners) in 1601. The process was patented in England by William Ellyot and Mathias Meysey in 1614. At that date, the "invention" could consist merely of the introduction of a new industry or product, or even a mere monopoly. They evidently soon transferred the patent to Sir Basil Brooke (metallurgist), Basil Brooke, but he was forced to surrender it in 1619. A cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New World
The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: Oxford University Press, p. 33: "[16c: from the feminine of ''Americus'', the Latinized first name of the explorer Amerigo Vespucci (1454–1512). The name ''America'' first appeared on a map in 1507 by the German cartographer Martin Waldseemüller, referring to the area now called Brazil]. Since the 16th century, the term "New World" has been used to describe the Western Hemisphere, often referred to as the Americas. Since the 18th century, it has come to represent the United States, which was initially colonial British America until it established independence following the American Revolutionary War. The second sense is now primary in English: ... However, the term is open to uncertainties: ..." The term arose in the early 16th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alumina
Aluminium oxide (or aluminium(III) oxide) is a chemical compound of aluminium and oxygen with the chemical formula . It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium oxide. It is commonly called alumina and may also be called aloxide, aloxite, ALOX or alundum in various forms and applications and alumina is refined from bauxite. It occurs naturally in its crystalline polymorphic phase α-Al2O3 as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire,which have an alumina content approaching 100%. Al2O3 is used as feedstock to produce aluminium metal, as an abrasive owing to its hardness, and as a refractory material owing to its high melting point. Natural occurrence Corundum is the most common naturally occurring crystalline form of aluminium oxide. Rubies and sapphires are gem-quality forms of corundum, which owe their characteristic colours to trace impurities. Rubies are given their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesse
Hesse or Hessen ( ), officially the State of Hesse (), is a States of Germany, state in Germany. Its capital city is Wiesbaden, and the largest urban area is Frankfurt, which is also the country's principal financial centre. Two other major historic cities are Darmstadt and Kassel. With an area of 21,114.73 square kilometers and a population of over six million, it ranks seventh and fifth, respectively, among the sixteen German states. Frankfurt Rhine-Main, Germany's second-largest metropolitan area (after Rhine-Ruhr), is mainly located in Hesse. As a cultural region, Hesse also includes the area known as Rhenish Hesse (Rheinhessen) in the neighboring state of Rhineland-Palatinate. Etymology The German name , like the names of other German regions ( "Swabia", "Franconia", "Bavaria", "Saxony"), derives from the dative plural form of the name of the inhabitants or German tribes, eponymous tribe, the Hessians (, singular ). The geographical name represents a short equivalent o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hessian Crucible
A Hessian crucible is a type of ceramic crucible that was manufactured in the Hesse region of Germany from the late Middle Ages through the Renaissance period. They were renowned for their ability to withstand very high temperatures, rapid changes in temperature, and strong reagents. These crucibles were widely used for alchemy and early metallurgy. Millions of the vessels were exported throughout Europe, Scandinavia, and the colonies in the Americas. The crucibles were made by firing kaolinitic clay at temperatures greater than 1100°C, forming mullite. Mullite is an aluminum silicate only described in the 20th century and is responsible for the excellent properties of the Hessian crucible. Main production centre of the Hessian crucibles was the village of Großalmerode Großalmerode (; or ''Grossalmerode'') is a town in the Werra-Meißner-Kreis in Hesse, Germany. Geography Location The small town, which has had town rights since 1775, lies 21 km east of Kassel in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medieval Era
In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similarly to the post-classical period of global history. It began with the fall of the Western Roman Empire and transitioned into the Renaissance and the Age of Discovery. The Middle Ages is the middle period of the three traditional divisions of Western history: classical antiquity, the medieval period, and the modern period. The medieval period is itself subdivided into the Early, High, and Late Middle Ages. Population decline, counterurbanisation, the collapse of centralised authority, invasions, and mass migrations of tribes, which had begun in late antiquity, continued into the Early Middle Ages. The large-scale movements of the Migration Period, including various Germanic peoples, formed new kingdoms in what remained of the Western Roman Empire. In the 7th century, North Africa and the Middle East—once part of the Byzantine Empire—came un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wootz Steel
Wootz steel is a crucible steel characterized by a pattern of bands and high carbon content. These bands are formed by sheets of microscopic carbides within a tempered martensite or pearlite matrix in higher-carbon steel, or by ferrite and pearlite banding in lower-carbon steels. It was a pioneering steel alloy developed in southern India in the mid-1st millennium BC and exported globally. History Wootz steel originated in the mid-1st millennium BC in India, wootz steel was made in Golconda in Telangana, Karnataka, Tamilnadu and Sri Lanka. The steel was exported as cakes of steely iron that came to be known as "wootz". The method was to heat black magnetite ore in the presence of carbon in a sealed clay crucible inside a charcoal furnace to completely remove slag. An alternative was to smelt the ore first to give wrought iron, then heat and hammer it to remove slag. The carbon source was bamboo and leaves from plants such as Avārai. Locals in Sri Lanka adopted the productio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crucible Steel
Crucible steel is steel made by melting pig iron, cast iron, iron, and sometimes steel, often along with sand, glass, ashes, and other fluxes, in a crucible. Crucible steel was first developed in the middle of the 1st millennium BCE in Southern India and Sri Lanka using the wootz process. In ancient times, it was not possible to produce very high temperatures with charcoal or coal fires, which were required to melt iron or steel. However, pig iron, having a higher carbon content and thus a lower melting point, could be melted, and by soaking wrought iron or steel in the liquid pig-iron for a long time, the carbon content of the pig iron could be reduced as it slowly diffused into the iron, turning both into steel. Crucible steel of this type was produced in South and Central Asia during the medieval era. This generally produced a very hard steel, but also a composite steel that was inhomogeneous, consisting of a very high-carbon steel (formerly the pig-iron) and a lower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alloys
An alloy is a mixture of chemical elements of which in most cases at least one is a metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have properties that differ from those of the pure elements from which they are made. The vast majority of metals used for commercial purposes are alloyed to improve their properties or behavior, such as increased strength, hardness or corrosion resistance. Metals may also be alloyed to reduce their overall cost, for instance alloys of gold and copper. A typical example of an alloy is 304 grade stainless steel which is commonly used for kitchen utensils, pans, knives and forks. Sometime also known as 18/8, it as an alloy consisting broadly of 74% iron, 18% chromium and 8% nickel. The chromium and nickel alloying elements add strength and hardness to the majority iron element, but their main function is to make it resistant to rust/corrosion. In an al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanten
Xanten (, Low Rhenish: ''Santen'') is a town in the state of North Rhine-Westphalia, Germany. It is located in the district of Wesel. Xanten is known for the Archaeological Park, one of the largest archaeological open air museums in the world, built at the site of the Roman settlements '' Colonia Ulpia Traiana''. Other attractions include the medieval town centre with Xanten Cathedral, many museums and large man-made lakes for various watersport activities. Xanten is visited by approximately one million tourists a year. It is also the only German town with a name that begins with ''X''. Geography Xanten is made up of three boroughs ('' Ortsteile''): ''Hochbruch'', ''Niederbruch'', and the ''town centre''. Other localities (''Bezirke'') belonging to the town of Xanten include ''Birten'', ''Lüttingen'', ''Marienbaum'', ''Vynen'', ''Obermörmter'', ''Wardt'', ''Mörmter'', ''Willich'', ''Beek'' and ''Ursel''. Parts of a nature reserve called ''Bislicher Insel'' a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colonia Ulpia Trajana
Xanten (, Low Rhenish: ''Santen'') is a town in the state of North Rhine-Westphalia, Germany. It is located in the district of Wesel. Xanten is known for the Archaeological Park, one of the largest archaeological open air museums in the world, built at the site of the Roman settlements ''Colonia Ulpia Traiana''. Other attractions include the medieval town centre with Xanten Cathedral, many museums and large man-made lakes for various watersport activities. Xanten is visited by approximately one million tourists a year. It is also the only German town with a name that begins with ''X''. Geography Xanten is made up of three boroughs (''Ortsteile''): ''Hochbruch'', ''Niederbruch'', and the ''town centre''. Other localities (''Bezirke'') belonging to the town of Xanten include ''Birten'', ''Lüttingen'', ''Marienbaum'', ''Vynen'', ''Obermörmter'', ''Wardt'', ''Mörmter'', ''Willich'', ''Beek'' and ''Ursel''. Parts of a nature reserve called ''Bislicher Insel'' are located in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
