Bronze - Wikipedia. Bronze is an alloy consisting primarily of copper, commonly with about 1. These additions produce a range of alloys that may be harder than copper alone, or have other useful properties, such as stiffness, ductility, or machinability. The archeological period where bronze was the hardest metal in widespread use is known as the Bronze Age. In the ancient Near East this began with the rise of Sumer in the 4th millennium BC, with India and China starting to use bronze around the same time; everywhere it gradually spread across regions. The Bronze Age was followed by the Iron Age starting from about 1. BC and reaching most of Eurasia by about 5. BC, though bronze continued to be much more widely used than it is in modern times. Because historical pieces were often made of brasses (copper and zinc) and bronzes with different compositions, modern museum and scholarly descriptions of older objects increasingly use the more inclusive term . This was the top tool of the period, and also seems to have been used as a store of value. The discovery of bronze enabled people to create metal objects which were harder and more durable than previously possible. Get access for hidden content, download links, clips, movies, texts and pics on Vintagepornbay & Tube: Please choose one of our Premium Memberships: Bronze Level. ECatsBridge - promoting real bridge in a virtual world. Telly Awards is the premier award honoring outstanding local, regional, and cable TV commercials and programs, as well as the finest video and film productions. ADFEST,ASIA PACIFIC ADVERTISING FESTIVAL. For all the latest ADFEST news,subscribe to ADFESTbuzz . Bronze tools, weapons, armor, and building materials such as decorative tiles were harder and more durable than their stone and copper (. Initially, bronze was made out of copper and arsenic, forming arsenic bronze, or from naturally or artificially mixed ores of copper and arsenic. Also, unlike arsenic, metallic tin and fumes from tin refining are not toxic. The earliest tin- alloy bronze dates to 4. BCE in a Vin. Tin sources and trade in ancient times had a major influence on the development of cultures. In Europe, a major source of tin was the British deposits of ore in Cornwall, which were traded as far as Phoenicia in the Eastern Mediterranean. In many parts of the world, large hoards of bronze artefacts are found, suggesting that bronze also represented a store of value and an indicator of social status. In Europe, large hoards of bronze tools, typically socketed axes (illustrated above), are found, which mostly show no signs of wear. With Chinese ritual bronzes, which are documented in the inscriptions they carry and from other sources, the case is very clear. These were made in enormous quantities for elite burials, and also used by the living for ritual offerings. Congratulations and sincere thanks to the independent authors and publishers who participated in our 20th annual, 2016 Independent Publisher Book Awards contest.Transition to iron. As cultures advanced from hand- wrought iron to machine- forged iron (typically made with trip hammers powered by water), blacksmiths learned how to make steel. Steel is stronger than bronze and holds a sharper edge longer. Alpha bronze alloys of 4–5% tin are used to make coins, springs, turbines and blades. Historical . The proportions of this mixture suggests that the candlestick was made from a hoard of old coins. The Benin Bronzes are really brass, and the Romanesque. Baptismal font at St Bartholomew's Church, Li. Bladed weapons were mostly cast from classic bronze, while helmets and armor were hammered from mild bronze. Commercial bronze (9. They are commonly used in architectural applications. It is able to hold a good polish and so is sometimes used in light reflectors and mirrors. By way of comparison, most bronzes are considerably less brittle than cast iron. Typically bronze only oxidizes superficially; once a copper oxide (eventually becoming copper carbonate) layer is formed, the underlying metal is protected from further corrosion. However, if copper chlorides are formed, a corrosion- mode called . They are generally about 1. Bronze is a better conductor of heat and electricity than most steels. The cost of copper- base alloys is generally higher than that of steels but lower than that of nickel- base alloys. Copper and its alloys have a huge variety of uses that reflect their versatile physical, mechanical, and chemical properties. Some common examples are the high electrical conductivity of pure copper, the low- friction properties of bearing bronze (bronze which has a high lead content— 6–8%), the resonant qualities of bell bronze (2. The melting point of bronze varies depending on the ratio of the alloy components and is about 9. Bronze is usually nonmagnetic, but certain alloys containing iron or nickel may have magnetic properties. Varieties of fitness. Bronze was especially suitable for use in boat and ship fittings prior to the wide employment of stainless steel owing to its combination of toughness and resistance to salt water corrosion. Bronze is still commonly used in ship propellers and submerged bearings. In the 2. 0th century, silicon was introduced as the primary alloying element, creating an alloy with wide application in industry and the major form used in contemporary statuary. Sculptors may prefer silicon bronze because of the ready availability of silicon bronze brazing rod, which allows colour- matched repair of defects in castings. Aluminium is also used for the structural metal aluminium bronze. It is also widely used for casting bronze sculptures. Many common bronze alloys have the unusual and very desirable property of expanding slightly just before they set, thus filling in the finest details of a mould. Bronze parts are tough and typically used for bearings, clips, electrical connectors and springs. Bronze also has very low friction against dissimilar metals, making it important for cannons prior to modern tolerancing, where iron cannonballs would otherwise stick in the barrel. Phosphor bronze is particularly suited to precision- grade bearings and springs. It is also used in guitar and piano strings. Unlike steel, bronze struck against a hard surface will not generate sparks, so it (along with beryllium copper) is used to make hammers, mallets, wrenches and other durable tools to be used in explosive atmospheres or in the presence of flammable vapors. Bronze is used to make bronze wool for woodworking applications where steel wool would discolour oak. Applications. It can be filled with oil to make the proprietary Oilite and similar material for bearings. Aluminium bronze is very hard and is used for bearings and machine tool ways. Many of the most famous Greek bronze sculptures are known through Roman copies in marble, which were more likely to survive. In India, bronze sculptures from the Kushana (Chausa hoard) and Gupta periods (Brahma from Mirpur- Khas, Akota Hoard, Sultanganj Buddha) and later periods (Hansi Hoard) have been found. The art form survives to this day, with many silpis, craftsmen, working in the areas of Swamimalai and Chennai. In antiquity other cultures also produced works of high art using bronze. For example: in Africa, the bronze heads of the Kingdom of Benin; in Europe, Grecian bronzes typically of figures from Greek mythology; in east Asia, Chinese ritual bronzes of the Shang and Zhou dynasty—more often ceremonial vessels but including some figurine examples. Bronze sculptures, although known for their longevity, still undergo microbial degradation; such as from certain species of yeasts. The reflecting surface was typically made slightly convex so that the whole face could be seen in a small mirror. Bronze was used for this purpose in many parts of the world, probably based on independent discoveries. Bronze mirrors survive from the Egyptian. Middle Kingdom (2. BCE). In Europe, the Etruscans were making bronze mirrors in the sixth century BCE, and Greek and Roman mirrors followed the same pattern. Although other materials such as speculum metal had come into use, bronze mirrors were still being made in Japan in the eighteenth century AD. Musical instruments. Annealed bronze continues to be made in the Himalayas. Bronze is the preferred metal for bells, in the form of a high tin bronze alloy known colloquially as bell metal, which is about 2. Nearly all professional cymbals are made from bronze, which gives a desirable balance of durability and timbre. Several types of bronze are used, commonly B2. B8 bronze which is made from 8% tin and 9. As the tin content in a bell or cymbal rises, the timbre drops. Bronze strings are commonly reserved on pianoforte for the lower pitch tones, as they possess a superior sustain quality to that of high- tensile steel. Examples include Tibetan singing bowls, temple bells of many sizes and shapes, gongs, Javanesegamelan and other bronze musical instruments. The earliest bronze archeological finds in Indonesia date from 1–2 BCE, including flat plates probably suspended and struck by a wooden or bone mallet. Bronze bells from Thailand and Cambodia date back to 3,6. BCE. Some companies are now making saxophones from phosphor bronze (3. The later usage was in part attributed to the choices of gold, silver and bronze to represent the first three Ages of Man in Greek mythology: the Golden Age, when men lived among the gods; the Silver age, where youth lasted a hundred years; and the Bronze Age, the era of heroes, and was first adopted at the 1. Summer Olympics. At the 1. Image gallery. British Museum. Retrieved 1. 4 September 2. Originally M. P. E. Berthelot, . 2. 94–8.^Originally Karl Lokotsch, Etymologisches W. Wolfgang Pfeifer, ed., Etymologisches W. A History of Metallurgy, Second Edition. London: Maney Publishing, for the Institute of Materials. ISBN 1- 9. 02. 65. Journal of Archaeological Science. Radivojevi. 6. 50. Antiquity Publications Ltd. Clayton E. What Caused The Iron Age? December 1. 0, 1. Oleg D. Sherby and Jeffrey Wadsworth. Ancient Blacksmiths, the Iron Age, Damascus Steels, and Modern Metallurgy. Tbermec 2. 00. 0, Las Vegas, Nevada December 4–8, 2. Retrieved on 2. 01. Knapp, Brian. Reed Library, Australia.^. Retrieved 1. 4 September 2. Retrieved 1. 4 September 2. Retrieved 1. 4 September 2. ASTM International. Retrieved 1. 4 September 2. Alavudeen; N. Venkateshwaran; J. Winowlin Jappes (1 January 2. A Textbook of Engineering Materials and Metallurgy. Firewall Media. ISBN 9. Retrieved 2. 5 June 2. ISBN9. 78- 0- 1. 9- 9.
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