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103-469: First acquired in 1970, the tank was to supplement Spain's fleet of M47 and M48 Patton United States tanks and to reduce Spain's reliance on American equipment in its army. The first 19 AMX-30 tanks were acquired from France in 1970, while another 280 were assembled in Spain. It was Spain's first mass-produced tank and developed the country's industry to the point where the government felt it could produce

206-412: 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

309-713: 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 ,

412-444: 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

515-442: A control unit that allowed the choice of ammunition for the gun and provided information on the ballistics of the round and the target to be engaged. As a result, the loader received a presentation unit to display information on which round to load into the gun's breech and to communicate ballistic data received, including angular velocity , wind velocity, gun elevation and vehicle inclination. The fire control system also allowed for

618-428: 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

721-445: 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

824-578: A modernization being applied to French AMX-30s. Ultimately, a mixed solution named Tecnología Santa Bárbara-Bazán (Santa Bárbara-Bazán Technology) (or TSB) was chosen. The improvement of the tank's mobility entailed replacing the HS-110 diesel engine with an MTU 833 Ka-501 diesel engine, producing 850 metric horsepower (625 kW), and the transmission with a German ZF LSG-3000, compatible with engines of up to 1,500 metric horsepower (1103 kW). The first 30 engines were to have 50% of

927-412: 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

1030-467: A needle-nose design, which improved armor protection of the turret front, an elongated turret bustle and storage bin which protruded halfway across the engine deck, and sloped sides to further improve ballistic protection; this gave the turret a decidedly lozenge-shaped profile. It also featured the M12 stereoscopic rangefinder, which was designed to improve first-round hit probability but proved difficult to use;

1133-534: 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

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1236-453: 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

1339-561: A tank on its own, leading to the development of the Lince tank project in 1985. It also offered Santa Bárbara Sistemas the experience which led to the production of the Leopard 2E in late 2003. Although final assembly was carried out by Santa Bárbara Sistemas, the production of the AMX-30E also included other companies in the country. Total production within Spain amounted to as much as 65% of

1442-672: 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

1545-403: 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

1648-403: 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

1751-453: 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 is extracted from iron ore by removing the oxygen through its combination with a preferred chemical partner such as carbon which

1854-408: 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

1957-535: 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

2060-691: 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

2163-514: 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 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

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2266-463: 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 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

2369-551: 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

2472-520: 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 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

2575-434: 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 the economies of melting and casting, can be heat treated after casting to make malleable iron or ductile iron objects. Steel

2678-400: 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 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

2781-457: 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 a brittle alloy commonly called pig iron . Alloy steel is steel to which other alloying elements have been intentionally added to modify

2884-441: 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 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

2987-547: 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

3090-498: 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 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

3193-655: 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

AMX-30E - Misplaced Pages Continue

3296-554: The Kanonenjagdpanzer in 1966. U.S. Army M47s remaining in storage were expended as targets. Additional equipment Background: History of the tank , Tank classification , Tanks in the Cold War Steel Steel 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

3399-644: The M41 Walker Bulldog , kept the tanks from Korea while engineers worked on a fix. Engineers improved production quality controls of the hydraulics by April 1952, and set about correcting M47s sidelined in storage. By then Army officials had scrapped plans to send the tanks to Korea, in favor of providing them to troops stationed in Europe and at home. The first M47s were not fielded to the 1st and 2nd Armored Divisions until summer 1952. Standardized in May 1952,

3502-599: 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

3605-554: 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 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

3708-607: The transmission . Both programs extended the vehicle's lifetime. Spain's fleet of AMX-30EM1s was replaced in the late 1990s by the German Leopard 2A4 , and the AMX-30EM2s were replaced by Centauro wheeled anti-tank vehicles in the early 21st century. Although 19 AMX-30Es were deployed to the Spanish Sahara in 1970, the tank never saw combat. In 1985 Indonesia expressed interest in the AMX-30E, while in 2004

3811-445: 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

3914-475: 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

4017-465: The 1957-58 Ifni War , the United States' ban on the usage of American ordnance supplied earlier as military aid to Spain pushed Spain to look for alternative equipment which could be freely employed in the Spanish Sahara . In the early 1960s, Spain looked towards its European neighbors for a new tank. The Spanish government first approached Krauss-Maffei , the German manufacturer of the Leopard 1 , and

4120-608: 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

4223-655: The Armored Cavalry Regiment Villaviciosa and the Armored Infantry Regiment Alcázar de Toledo , receiving 23 and 44 tanks, respectively. On 27 March 1979, prior to the end of production of the first batch, the Spanish Army and Santa Bárbara Sistemas signed a contract for the production and delivery of a second batch of 100 AMX-30Es. In 1980, after the 200th AMX-30E was delivered to the Spanish Army,

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4326-776: The British Centurion main battle tank and the M47 as standard. By October the at Camp Drum in July, the New Jersey Army National Guard was the first reserve force to train with the tank. The Marine Corps also fielded M47s starting in late 1952; after the Korean War, all seven Marine tank battalions, three divisional, two reserve training, and two force level, each fielded M47s. But these were soon replaced with M48A1 Pattons and M103 heavy tanks , with

4429-557: The French offer to allow Spain to manufacture the tank, that led the Spanish Army to favor the French armored vehicle. On 22 June 1970, the Spanish Ministry of Defense signed an agreement of military cooperation with France, which outlined plans for the future acquisition of around 200 tanks for the Spanish Army. Of these, 180 were to be manufactured under license in Spain and 20 were to be manufactured by France. Ultimately, GIAT

4532-576: The Leopard's 2.6 meters (8.5 feet). In terms of lethality, the AMX-30's Obus G high-explosive anti-tank (HEAT) round was one of the most advanced projectiles at the time. Because HEAT warheads become less efficient during spin stabilization induced by the rifling of a tank-gun barrel, the Obus G was designed so that the shaped charge warhead was mounted on ball bearings within an outer casing, allowing

4635-470: 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

4738-616: The M47 Patton's production ran until November 1953; Detroit built 5,481 tanks, and American Locomotive Company (Alco) produced 3,095, for a total production run of 8,576 M47 Pattons. After the U.S. Army in Germany was equipped with the M47, the first M47s delivered under the Mutual Security Agency program were delivered to Portugal in 1952. In October the agency announced that NATO member nations had agreed to adopt

4841-830: The M47s were exported in the late 1950s. Out of the 8,576 M47s built, 8,552 (99.7 percent) were transferred to other countries through the Major Defense Acquisition Program (MDAP) during the 1950s, forming the backbone of the NATO tank force for nearly 15 years. The M47 was widely used by many countries, especially NATO and SEATO allies, including Austria (147), Belgium (784), Ethiopia (30), France (856), Greece (396), Portugal (161), from USA and West Germany), Iran (around 400), Italy (2,480), Japan (1 for evaluation only), Jordan (49), Pakistan (100), Portugal (161), Saudi Arabia (23 from

4944-589: The M48 series before long. After being declared obsolete in 1957, M46s and M47s were retained in active duty infantry division battlegroup assault gun platoons (four tanks each, one platoon per battlegroup, for a total of 20 tanks per division) until replaced with the light truck-mounted SS-10 anti-tank guided missile in the early 1960s. M47s were used by the Reserves for a relatively short time, soon being replaced by early production M48 Patton series tanks; thus, most of

5047-465: The Spanish and Colombian governments discussed the possible sale of around 40 AMX-30EM2s. Both trade deals fell through. In 1960, Spain's tank fleet was composed mainly of American M47 Patton tanks, with some newer M48 Patton tanks. The M47s had been acquired by the Spanish army in the mid-1950s, replacing the previous fleet of 1930s-vintage Panzer I , T-26 and Panzer IV tank designs. During

5150-577: The US, 108 on the international market), Somalia (25 from Saudi Arabia), South Korea (531), Sudan (17 from Saudi Arabia), Spain (389), Switzerland (2 for evaluation), Turkey (1,347 from the US and West Germany), West Germany (1,120), and Yugoslavia (319). Like the US Army of the time, the West German Bundeswehr also used the M47 in a tank destroyer role until replacing them with

5253-606: The United Kingdom's Labour Party on the basis that the Leopard's 105-millimeter (4.13 in) L7 tank gun was British technology. Meanwhile, Spain tested the French AMX-30 between 2 and 10 June 1964. The Leopard 1 and the AMX-30 originated from a joint tank development program known as the Europanzer. For a tank, the AMX-30 had a low silhouette; the height of the tank was 2.28 meters (7.5 feet), compared to

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5356-436: 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

5459-471: 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

5562-494: 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

5665-521: 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 a higher than 2.1% carbon content are known as cast iron . With modern steelmaking techniques such as powder metal forming, it

5768-696: The company applied for an export license from the German Economics Ministry. Spain's status as a non- NATO country meant that the decision to grant the export license had to be reviewed by the Bundessicherheitsrat ( Federal Security Council  [ de ] ), or the BSR, which was responsible for the coordination of the national defense policy. Ultimately, the council ruled that Krauss-Maffei could sign an export contract with Spain. The deal was, however, stalled by pressure from

5871-498: The day and during night operations, and increased the likelihood of a first round impact. The fire control system was also modernized through the exchange of the old M282 gunner's periscope with a new periscope and a new Nd:YAG laser rangefinder . A new ballistics computer, the NSC-800, was issued, as well as a new digital panel for the gunner, designed and manufactured by the Spanish company INISEL. The tank commander also received

5974-422: 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 a hard oxide forms on the metal surface; this

6077-565: The early 21st century. The other 149 AMX-30Es were reconstructed to improve their mobility. The reconstruction consisted of the replacement of the original French transmission with the American Allison CD-850-6A. Furthermore, several parts of the tank, such as the brakes, were renovated in order to bring them up to their original standards. The CD-850-6A was an automatic transmission, with a triple differential providing two forward velocities and one reverse velocity. However,

6180-476: The engine manufactured in Spain; the rest, 73% were to be produced indigenously. This new engine gave the modernized tank a power ratio of 23 metric horsepower per tonne (21.13 hp/S/T). The new engine was coupled with the AMX-30B2's improved torsion-bar suspension, which used larger diameter torsion-bars and new shocks. To improve the tank's firepower, the gun mount around the loader's turret hatch

6283-413: 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 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

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6386-648: 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

6489-465: The first batch, was 45 million pesetas (US$ 642,800). Cost per tank increased during the second batch to 62 million pesetas (885,700 dollars). Although brand new, the AMX-30E entered service with automotive issues, including problems with the antiquated 5SD-200D transmission. Consequently, as the first production batch began to end, the Spanish Army and Santa Bárbara Sistemas began to study possible upgrades. The main objectives were to increase

6592-513: 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

6695-529: The future upgrade to a more sophisticated stabilization system for the tank's main gun. Survivability improvements included the addition of new steel side-skirts, a new smoke generating system linked to the engine and a new fire suppression system. One hundred fifty AMX-30Es received this modernization package and were designated AMX-30EM2s. The program began in 1989 and ended in 1993. Ultimately, Spain's AMX-30EM2s were replaced by brand-new Centauro anti-tank vehicles, which were partially manufactured in Spain, in

6798-599: 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

6901-583: The issue arose from their own expedient decision to use lower grades of steel to circumvent wartime shortages. Chrysler laid off about 1000 workers at Detroit Tank Arsenal when it wrapped up production in November. American Locomotive resumed production in November. The company closed its tank division in June 1954. With the arrival of the improved M48 Patton in 1953, the M47 was declared "limited standard" in 1955, and examples in tank units were replaced with

7004-660: The last M47s being retired in 1959. American Locomotive production was halted in October when the company's ordnance and locomotive divisions went on strike. Production resumed in February when union leaders agreed to a pay raise. In December 1952 the Defense Department ordered cutbacks to M47 and M48 tank production. In November 1953 American Locomotive halted production of the M47 after operators found drive gear defects in Europe. Army officials quickly acknowledged

7107-439: 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

7210-618: The modernization of its armed forces. Of the possible armaments for sale, Indonesia expressed interest in the procurement of the AMX-30. Although this deal fell through, in 2004 the Spanish and Colombian governments agreed on the sale of between 33 and 46 second-hand AMX-30EM2s, which had recently been replaced in the Spanish Army. However, the deal was canceled after José María Aznar was replaced by José Luis Rodríguez Zapatero as prime minister of Spain—the new Spanish government declared that Spain didn't even have enough AMX-30EM2s in working condition to sell to Colombia. Background: History of

7313-450: 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

7416-479: The new cartridge case does not chamber in the weaker guns). The secondary armament consisted of two .30 cal Browning machine guns, one in the bow and one coaxial with the 90mm main gun in the turret, and a .50 caliber Browning M2 on a pintle mount on the turret roof. The M47 was the last American-designed tank to include a bow machine gun. The T42 turret had a larger turret ring than the M26/M46 turret, and featured

7519-441: The new transmission resulted in a new problem. The excessive heat produced by the transmission reduced the vehicle's range. The reconstruction of the 149 AMX-30Es began in 1988, and these were designated AMX-30EM1s. In the early 1990s Spain received a large number of M60 Patton tanks, replacing its fleet of M47s and M48s, as well as its AMX-30EM1s. In the mid-1980s Indonesia approached Spain in an attempt to procure armaments for

7622-497: The next 40 would have 40% of the vehicle manufactured in Spain. The other 120 had 65% of the tank manufactured in the country. Production began in 1974, at a rate of five tanks per month, and ended on 25 June 1979. The first five tanks were delivered to the Uad Ras Mechanized Infantry Regiment on 30 October 1974. This batch also replaced the M41 Walker Bulldog light tanks and M48 Patton tanks in

7725-480: The onset of the Korean War. As a result, Detroit's newly unemployed automotive workers found little work, while tank manufacturers outside Michigan lacked skilled workers. Truman's policy also counted on civilian factories being able to quickly transition to war-time production. However, many factories lacked needed tank production machinery, done away with during World War II demobilization. A faulty Ordnance Corps -designed hydraulic turret-control mechanism, shared by

7828-436: 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 a subsequent step. Other materials are often added to the iron/carbon mixture to produce steel with

7931-437: The power and the reliability of the power pack, an improvement to the tank's firepower and accuracy, as well as to increase the vehicle's ballistic protection and overall survivability. A number of modernization packages were proposed, including a suggestion to mount the AMX-30E's turret on a Leopard 1's chassis. Other options included swapping the existing power pack for a new American diesel engine and transmission or exchanging

8034-468: The power pack for a new German diesel engine and transmission. More austere versions of these same options were offered, pairing the existing HS-110 engine with the already mentioned transmissions. Another prototype was produced using the Leopard's more modern tracks, and another similar prototype mounted a new 12.7-millimeter (0.5 in) machine gun for the loader's position. France's GIAT also offered to modernize Spain's AMX-30Es to AMX-30B2 standards,

8137-449: 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

8240-759: 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

8343-605: The rangefinder protruded from both sides of the upper turret front, which would be a feature of American tanks until the advent of the M1 Abrams in 1980. Production at American Locomotive began in July 1951. Logistical and technical issues plagued production almost from the start. Truman administration policy sought to strengthen American arms makers' resilience to aerial attack by encouraging more decentralized weapons production – away from Detroit. The U.S. curtailed civilian automotive production to boost military production with

8446-526: The round to be spin stabilized through the rifling of the gun without affecting the warhead inside. The Obus G was designed to penetrate up to 400 millimetres (16 inches) of steel armor . On the other hand, the Leopard was armed with the L7A3 tank gun , capable of penetrating the frontal armor of most contemporary tanks. Although the Leopard boasted greater armor than the AMX-30—partially accounting for

8549-477: 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 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

8652-401: 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

8755-561: 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

8858-665: The tank , Tank classification , Tanks in the Cold War M47 Patton The M47 Patton was an American medium tank , a development of the M46 Patton mounting an updated turret, and was in turn further developed as the M48 Patton . It was the second American tank to be named after General George S. Patton , commander of the U.S. Third Army during World War II and one of the earliest American advocates of tanks in battle. The M47

8961-646: The tank's patent was awarded to Spain. This allowed minor modifications to be done to the vehicle without having to consult GIAT. It also meant that the degree of local construction of each vehicle augmented considerably. Production of the second batch lasted between 1979 and 1983. By the time production ended, the Spanish Army fielded 299 AMX-30Es (280 produced between 1974 and 1983, and 19 delivered from France in 1970) and 4 training vehicles delivered in 1975. Santa Bárbara Sistemas also manufactured 18 Roland España (denominated AMX-30RE) anti-air vehicles and 10 AMX-30D armored recovery vehicles . The average cost per tank, in

9064-544: The tank. Spain's AMX-30E fleet went through two separate modifications in the late 1980s, a modernization program and a reconstruction program. The former, named the AMX-30EM2 (150 tanks), sought to modernize and improve the vehicle's automotive characteristics, while the latter, or the AMX-30EM1 (149 tanks), resulted in a more austere improvement of the tank's power plant by maintaining the existing engine and replacing

9167-561: 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

9270-525: 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

9373-453: The weight difference between the two tanks—the latter was sold at a cheaper price. In May 1970, the Spanish government decided to sign a contract with the French company GIAT to begin production of the AMX-30. However, it was not the advantages of the French vehicle itself that influenced the decision. Rather, it was the UK's unwillingness to sell their L7 tank-gun, the low cost of the AMX-30, and

9476-428: 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 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

9579-687: Was contracted to manufacture 19 tanks. These were delivered to the Spanish Legion 's Bakali company, deployed in the Spanish Sahara. The first six AMX-30s were delivered by rail to the Spanish border city of Irún , in the Basque Country , and then transferred to Bilbao. Finally, they were shipped by the Spanish Navy , on the transport Almirante Lobo , to El Aaiún in the Spanish Sahara. This unit existed until 1975, when it

9682-573: Was deemed that there was not enough time to finish the development of the T42. The final decision was to produce another interim solution, with the turret of the T42 mounted on the existing M46 hull. Although this interim tank was itself technically immature, Army officials felt the improvements over the M46 in firepower and armor were worth the risk. The composite tank, developed by the Detroit Arsenal ,

9785-718: 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

9888-616: Was disbanded and its tanks transferred to the Uad-Ras Mechanized Infantry Regiment. This agreement laid the foundations for the upcoming tank plant at the industrial polygon of Las Canteras , near the town of Alcalá de Guadaíra . Several parts of the tank were subcontracted to other Spanish companies, including Astilleros Españoles (turret), Boetticher , Duro Felguera and E. N. Bazán . The grade of local production varied per batch. The first 20 tanks were to have 18% of each vehicle manufactured in Spain;

9991-509: 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

10094-433: Was modified to allow the installation of a 12.7-millimeter (0.5 in) machine gun, while the main gun's firepower was augmented through the introduction of the new CETME437A armor-piercing, fin-stabilized discarding sabot (APFSDS). The gun's accuracy was improved through the installation of the new Mark 9 modification A/D fire control system, designed by Hughes Aircraft Company . The new system allowed firing during

10197-604: Was named the M47 Patton. In December 1950 the Army awarded a $ 100 million contract to the American Locomotive Company for the production of 500 tanks. It entered production in 1951. Its main gun was the M36 (T119E1) 90 mm gun with an M12 optical rangefinder fitted, which was developed as a more powerful version of the earlier 90 mm guns and were backwards-compatible with their ammunition (but not vice versa,

10300-438: 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

10403-757: 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

10506-525: Was the U.S. Army's and Marine Corps' primary tank, intended to replace the M26 Pershing and M46 Patton medium tanks. The M47 was widely used by U.S. Cold War allies, both SEATO and NATO countries, and was the only Patton series tank that never saw combat while in US service. Although the later M48s and M60s were similar in appearance, those were completely new tank designs. Many different M47 Patton models remain in service internationally. The M47

10609-558: Was the last US tank to have a bow-mounted machine gun in the hull. Although a new power plant corrected the mobility and reliability problems of the M26 Pershing , the subsequently renamed M46 was considered a stopgap solution that would be replaced later by the T42 medium tank . However, after fighting erupted in Korea , the Army decided that it needed the new tank earlier than planned. It

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