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77-573: Kinta District was once famous for its tin , being one of the major tin producers in the 18th century. The discovery of substantial tin deposits in the Kinta Valley attracted a diverse influx of immigrants, particularly from China, who sought their fortunes in the lucrative mining trade. A railway line linking Ipoh and other town in Kinta such as Pusing, Papan, Siputeh and Tronoh was completed in 1909 and used to transport tin ore. The tracks were dismantled by

154-539: A (nominal) stress-strain curve, because the peak (representing the onset of necking) is often relatively flat. Moreover, some (brittle) materials fracture before the onset of necking, such that there is no peak. In practice, for many purposes it is preferable to carry out a different kind of test, designed to evaluate the toughness (energy absorbed during fracture), rather than use ductility values obtained in tensile tests. In an absolute sense, "ductility" values are therefore virtually meaningless. The actual (true) strain in

231-412: A genuinely meaningful parameter. One objection is that it is not easy to measure accurately, particularly with samples that are not circular in section. Rather more fundamentally, it is affected by both the uniform plastic deformation that took place before necking and by the development of the neck. Furthermore, it is sensitive to exactly what happens in the latter stages of necking, when the true strain

308-502: A high ferrite content. This famously resulted in serious hull cracking in Liberty ships in colder waters during World War II , causing many sinkings. DBTT can also be influenced by external factors such as neutron radiation , which leads to an increase in internal lattice defects and a corresponding decrease in ductility and increase in DBTT. The most accurate method of measuring the DBTT of

385-532: A major "tin crisis" ensued—tin was delisted from trading on the London Metal Exchange for about three years. ITC dissolved soon afterward, and the price of tin, now in a free-market environment, fell to $ 4 per pound and remained around that level through the 1990s. The price increased again by 2010 with a rebound in consumption following the 2007–2008 economic crisis , accompanying restocking and continued growth in consumption. London Metal Exchange (LME)

462-546: A material is by fracture testing . Typically four-point bend testing at a range of temperatures is performed on pre-cracked bars of polished material. Two fracture tests are typically utilized to determine the DBTT of specific metals: the Charpy V-Notch test and the Izod test. The Charpy V-notch test determines the impact energy absorption ability or toughness of the specimen by measuring the potential energy difference resulting from

539-521: A material is cooled below the DBTT, it has a much greater tendency to shatter on impact instead of bending or deforming ( low temperature embrittlement ). Thus, the DBTT indicates the temperature at which, as temperature decreases, a material's ability to deform in a ductile manner decreases and so the rate of crack propagation drastically increases. In other words, solids are very brittle at very low temperatures, and their toughness becomes much higher at elevated temperatures. For more general applications, it

616-526: A phenomenon known as " tin pest " or "tin disease". Some unverifiable sources also say that, during Napoleon 's Russian campaign of 1812, the temperatures became so cold that the tin buttons on the soldiers' uniforms disintegrated over time, contributing to the defeat of the Grande Armée , a persistent legend. The α-β transformation temperature is 13.2 °C (55.8 °F), but impurities (e.g. Al, Zn, etc.) lower it well below 0 °C (32 °F). With

693-796: A similar mechanical property, is characterized by a material's ability to deform plastically without failure under compressive stress. Historically, materials were considered malleable if they were amenable to forming by hammering or rolling. Lead is an example of a material which is relatively malleable but not ductile. Ductility is especially important in metalworking , as materials that crack, break or shatter under stress cannot be manipulated using metal-forming processes such as hammering , rolling , drawing or extruding . Malleable materials can be formed cold using stamping or pressing , whereas brittle materials may be cast or thermoformed . High degrees of ductility occur due to metallic bonds , which are found predominantly in metals; this leads to

770-552: A solution with most metals and elements so tin does not have much solid solubility. Tin mixes well with bismuth , gallium , lead , thallium and zinc , forming simple eutectic systems. Tin becomes a superconductor below 3.72  K and was one of the first superconductors to be studied. The Meissner effect , one of the characteristic features of superconductors, was first discovered in superconducting tin crystals. Tin resists corrosion from water , but can be corroded by acids and alkalis . Tin can be highly polished and

847-1205: A tension test are relative elongation (in percent, sometimes denoted as ε f {\displaystyle \varepsilon _{f}} ) and reduction of area (sometimes denoted as q {\displaystyle q} ) at fracture. Fracture strain is the engineering strain at which a test specimen fractures during a uniaxial tensile test . Percent elongation, or engineering strain at fracture, can be written as: % E L = final gauge length - initial gauge length initial gauge length = l f − l 0 l 0 ⋅ 100 {\displaystyle \%EL={\frac {\text{final gauge length - initial gauge length}}{\text{initial gauge length}}}={\frac {l_{f}-l_{0}}{l_{0}}}\cdot 100} Percent reduction in area can be written as: % R A = change in area original area = A 0 − A f A 0 ⋅ 100 {\displaystyle \%RA={\frac {\text{change in area}}{\text{original area}}}={\frac {A_{0}-A_{f}}{A_{0}}}\cdot 100} where

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924-608: A tin or tin-lead coolant, the tin would first have to go through isotopic separation to remove the isotopes with odd mass number. Combined, these three isotopes make up about 17% of natural tin but represent nearly all of the capture cross section. Of the remaining seven isotopes tin-112 has a capture cross section of 1 barn. The other six isotopes forming 82.7% of natural tin have capture cross sections of 0.3 barns or less, making them effectively transparent to neutrons. Tin has 31 unstable isotopes, ranging in mass number from 99 to 139. The unstable tin isotopes have half-lives of less than

1001-448: A year except for tin-126 , which has a half-life of about 230,000 years. Tin-100 and tin-132 are two of the very few nuclides with a " doubly magic " nucleus which despite being unstable, as they have very uneven neutron–proton ratios , are the endpoints beyond which tin isotopes lighter than tin-100 and heavier than tin-132 are much less stable. Another 30 metastable isomers have been identified for tin isotopes between 111 and 131,

1078-681: Is applied to the material. Thus, in materials with a lower amount of slip systems, dislocations are often pinned by obstacles leading to strain hardening, which increases the materials strength which makes the material more brittle. For this reason, FCC (face centered cubic) structures are ductile over a wide range of temperatures, BCC (body centered cubic) structures are ductile only at high temperatures, and HCP (hexagonal closest packed) structures are often brittle over wide ranges of temperatures. This leads to each of these structures having different performances as they approach failure (fatigue, overload, and stress cracking) under various temperatures, and shows

1155-467: Is evidence that Cornwall in the first centuries AD was the main source of tin. Tin extraction and use can be dated to the beginnings of the Bronze Age around 3000 BC, when it was observed that copper objects formed of polymetallic ores with different metal contents had different physical properties. The earliest bronze objects had a tin or arsenic content of less than 2% and are believed to be

1232-563: Is generated via the long s -process in low-to-medium mass stars (with masses of 0.6 to 10 times that of the Sun ), and finally by beta decay of the heavy isotopes of indium . Tin is the 49th most abundant element in Earth's crust , representing 2  ppm compared with 75 ppm for zinc, 50 ppm for copper, and 14 ppm for lead. Tin does not occur as the native element but must be extracted from various ores. Cassiterite ( SnO 2 )

1309-410: Is no dependence for properties such as stiffness, yield stress and ultimate tensile strength). This occurs because the measured strain (displacement) at fracture commonly incorporates contributions from both the uniform deformation occurring up to the onset of necking and the subsequent deformation of the neck (during which there is little or no deformation in the rest of the sample). The significance of

1386-591: Is often becoming very high and the behavior is of limited significance in terms of a meaningful definition of strength (or toughness). There has again been extensive study of this issue. Metals can undergo two different types of fractures: brittle fracture or ductile fracture. Failure propagation occurs faster in brittle materials due to the ability for ductile materials to undergo plastic deformation. Thus, ductile materials are able to sustain more stress due to their ability to absorb more energy prior to failure than brittle materials are. The plastic deformation results in

1463-404: Is preferred to have a lower DBTT to ensure the material has a wider ductility range. This ensures that sudden cracks are inhibited so that failures in the metal body are prevented. It has been determined that the more slip systems a material has, the wider the range of temperatures ductile behavior is exhibited at. This is due to the slip systems allowing for more motion of dislocations when a stress

1540-524: Is soft enough to be cut with little force, and a bar of tin can be bent by hand with little effort. When bent, the so-called " tin cry " can be heard as a result of twinning in tin crystals. Tin is a post-transition metal in group 14 of the periodic table of elements. It is obtained chiefly from the mineral cassiterite , which contains stannic oxide , SnO 2 . Tin shows a chemical similarity to both of its neighbors in group 14, germanium and lead , and has two main oxidation states , +2 and

1617-528: Is the least common stable isotope. The isotopes with even mass numbers have no nuclear spin , while those with odd mass numbers have a nuclear spin of 1/2. It is thought that tin has such a great multitude of stable isotopes because of tin's atomic number being 50, which is a " magic number " in nuclear physics. Tin is one of the easiest elements to detect and analyze by NMR spectroscopy , which relies on molecular weight and its chemical shifts are referenced against tetramethyltin ( SnMe 4 ). Of

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1694-492: Is the most ductile of all metals in pure form. However, not all metals experience ductile failure as some can be characterized with brittle failure like cast iron . Polymers generally can be viewed as ductile materials as they typically allow for plastic deformation. Inorganic materials, including a wide variety of ceramics and semiconductors, are generally characterized by their brittleness. This brittleness primarily stems from their strong ionic or covalent bonds, which maintain

1771-590: Is the nonmetallic form. It is stable below 13.2 °C (55.8 °F) and is brittle . α-tin has a diamond cubic crystal structure, as do diamond and silicon . α-tin does not have metallic properties because its atoms form a covalent structure in which electrons cannot move freely. α-tin is a dull-gray powdery material with no common uses other than specialized semiconductor applications. γ-tin and σ-tin exist at temperatures above 161 °C (322 °F)  and pressures above several GPa . In cold conditions β-tin tends to transform spontaneously into α-tin,

1848-443: Is the only commercially important source of tin, although small quantities of tin are recovered from complex sulfides such as stannite , cylindrite , franckeite , canfieldite , and teallite . Minerals with tin are almost always associated with granite rock, usually at a level of 1% tin oxide content. Because of the higher specific gravity of tin dioxide, about 80% of mined tin is from secondary deposits found downstream from

1925-529: Is the original length before testing. This formula helps in quantifying how much a material can stretch under tensile stress before failure, providing key insights into its ductile behavior. Ductility is an important consideration in engineering and manufacturing. It defines a material's suitability for certain manufacturing operations (such as cold working ) and its capacity to absorb mechanical overload like in an engine. Some metals that are generally described as ductile include gold and copper , while platinum

2002-628: Is tin's principal trading site. Other tin contract markets are Kuala Lumpur Tin Market (KLTM) and Indonesia Tin Exchange (INATIN). Due to factors involved in the 2021 global supply chain crisis , tin prices almost doubled during 2020–21 and have had their largest annual rise in over 30 years. Global refined tin consumption dropped 1.6 percent in 2020 as the COVID-19 pandemic disrupted global manufacturing industries. In 2018, just under half of all tin produced

2079-425: Is used as a protective coat for other metals. When heated in air it oxidizes slowly to form a thin passivation layer of stannic oxide ( SnO 2 ) that inhibits further oxidation. Tin has ten stable isotopes , the greatest number of any element. Their mass numbers are 112, 114, 115, 116, 117, 118, 119, 120, 122, and 124. Tin-120 makes up almost a third of all tin. Tin-118 and tin-116 are also common. Tin-115

2156-444: Is widely used for food packaging as " tin cans ". Some organotin compounds can be extremely toxic. Tin is a soft, malleable , ductile and highly crystalline silvery-white metal . When a bar of tin is bent a crackling sound known as the " tin cry " can be heard from the twinning of the crystals. This trait is shared by indium , cadmium , zinc , and mercury in its solid state. Tin melts at about 232 °C (450 °F),

2233-505: The r -process (rapid neutron capture) in supernovae and neutron star mergers . Tin isotopes 115, 117 through 120, and 122 are produced via both the s -process and the r -process, The two lightest stable isotopes, tin-112 and tin-114, cannot be made in significant amounts in the s - or r -processes and are among the p-nuclei whose origins are not well understood. Some theories about their formation include proton capture and photodisintegration . Tin-115 might be partially produced in

2310-454: The Bronze Age . In modern times, tin is used in many alloys, most notably tin-lead soft solders , which are typically 60% or more tin, and in the manufacture of transparent, electrically conducting films of indium tin oxide in optoelectronic applications. Another large application is corrosion -resistant tin plating of steel . Because of the low toxicity of inorganic tin, tin-plated steel

2387-508: The diamond cubic structure. Metallic tin does not easily oxidize in air and water. The first tin alloy used on a large scale was bronze , made of 1 ⁄ 8  tin and 7 ⁄ 8   copper (12.5% and 87.5% respectively), from as early as 3000 BC. After 600 BC, pure metallic tin was produced. Pewter , which is an alloy of 85–90% tin with the remainder commonly consisting of copper , antimony , bismuth, and sometimes lead and silver, has been used for flatware since

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2464-608: The s -process, both directly and as the daughter of long-lived indium-115 , and also from the decay of indium-115 produced via the r -process. The word tin is shared among Germanic languages and can be traced back to reconstructed Proto-Germanic * tin-om ; cognates include German Zinn , Swedish tenn and Dutch tin . It is not found in other branches of Indo-European , except by borrowing from Germanic (e.g., Irish tinne from English). The Latin name for tin, stannum , originally meant an alloy of silver and lead, and came to mean 'tin' in

2541-450: The Charpy test, with the only differentiating factor being the placement of the sample; In the former the sample is placed vertically, while in the latter the sample is placed horizontally with respect to the bottom of the base. For experiments conducted at higher temperatures, dislocation activity increases. At a certain temperature, dislocations shield the crack tip to such an extent that

2618-659: The Japanese during World War II and were never rebuilt. Shortly after the war ended, the tin industry deteriorated in Kinta. Kinta District is divided into 5 mukims , which are: Kinta District is divided into 2 local authorities: The district and land officer is also divided into Ipoh and Batu Gajah, and the Kinta District Office is centered at Batu Gajah. Some areas in Sungai Raia such as RPT Tekah 1, RPT Tekah 2, RTC Gopeng & Gopeng Industrial Park are administered by

2695-731: The Kampar District Council even though they are located in the Kinta district. The following is based on Department of Statistics Malaysia 2020 census. List of Kinta district representatives in the Federal Parliament ( Dewan Rakyat ) List of Kinta district representatives in the State Legislative Assembly of Perak Tin Tin is a chemical element ; it has symbol Sn (from Latin stannum ) and atomic number 50. A silvery-colored metal, tin

2772-459: The Near East where arsenic is commonly found with copper ore, but the health risks were quickly realized and the quest for sources of the much less hazardous tin ores began early in the Bronze Age. This created the demand for rare tin metal and formed a trade network that linked the distant sources of tin to the markets of Bronze Age cultures. Cassiterite ( SnO 2 ), the oxide form of tin,

2849-637: The United States has neither mined (since 1993) nor smelted (since 1989) tin, it was the largest secondary producer, recycling nearly 14,000 tonnes in 2006. New deposits are reported in Mongolia , and in 2009, new deposits of tin were discovered in Colombia. Tin is produced by carbothermic reduction of the oxide ore with carbon or coke. Both reverberatory furnace and electric furnace can be used: The ten largest tin-producing companies produced most of

2926-496: The addition of antimony or bismuth the transformation might not occur at all, increasing durability. Commercial grades of tin (99.8% tin content) resist transformation because of the inhibiting effect of small amounts of bismuth, antimony, lead, and silver present as impurities. Alloying elements such as copper, antimony, bismuth, cadmium, and silver increase the hardness of tin. Tin easily forms hard, brittle intermetallic phases that are typically undesirable. It does not mix into

3003-441: The area of concern is the cross-sectional area of the gauge of the specimen. According to Shigley's Mechanical Engineering Design, significant denotes about 5.0 percent elongation. An important point concerning the value of the ductility (nominal strain at failure) in a tensile test is that it commonly exhibits a dependence on sample dimensions. However, a universal parameter should exhibit no such dependence (and, indeed, there

3080-556: The arts to stain porcelain . Malleable Ductility refers to the ability of a material to sustain significant plastic deformation before fracture. Plastic deformation is the permanent distortion of a material under applied stress, as opposed to elastic deformation, which is reversible upon removing the stress. Ductility is a critical mechanical performance indicator, particularly in applications that require materials to bend, stretch, or deform in other ways without breaking. The extent of ductility can be quantitatively assessed using

3157-690: The atoms in a rigid, densely packed arrangement. Such a rigid lattice structure restricts the movement of atoms or dislocations, essential for plastic deformation. The significant difference in ductility observed between metals and inorganic semiconductor or insulator can be traced back to each material’s inherent characteristics, including the nature of their defects, such as dislocations, and their specific chemical bonding properties. Consequently, unlike ductile metals and some organic materials with ductility (% EL) from 1.2% to over 1200%, brittle inorganic semiconductors and ceramic insulators typically show much smaller ductility at room temperature. Malleability ,

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3234-409: The collision between a mass on a free-falling pendulum and the machined V-shaped notch in the sample, resulting in the pendulum breaking through the sample. The DBTT is determined by repeating this test over a variety of temperatures and noting when the resulting fracture changes to a brittle behavior which occurs when the absorbed energy is dramatically decreased. The Izod test is essentially the same as

3311-405: The common perception that metals are ductile in general. In metallic bonds valence shell electrons are delocalized and shared between many atoms. The delocalized electrons allow metal atoms to slide past one another without being subjected to strong repulsive forces that would cause other materials to shatter. The ductility of steel varies depending on the alloying constituents. Increasing

3388-588: The complex agreements between producer countries and consumer countries dating back to 1921. Earlier agreements tended to be somewhat informal and led to the "First International Tin Agreement" in 1956, the first of a series that effectively collapsed in 1985. Through these agreements, the International Tin Council (ITC) had a considerable effect on tin prices. ITC supported the price of tin during periods of low prices by buying tin for its buffer stockpile and

3465-424: The contribution from neck development depends on the "aspect ratio" (length / diameter) of the gauge length, being greater when the ratio is low. This is a simple geometric effect, which has been clearly identified. There have been both experimental studies and theoretical explorations of the effect, mostly based on Finite Element Method (FEM) modelling. Nevertheless, it is not universally appreciated and, since

3542-426: The dislocations require a larger stress to cross the grain boundaries and continue to propagate throughout the material. It has been shown that by continuing to refine ferrite grains to reduce their size, from 40 microns down to 1.3 microns, that it is possible to eliminate the DBTT entirely so that a brittle fracture never occurs in ferritic steel (as the DBTT required would be below absolute zero). In some materials,

3619-586: The fourth century —the earlier Latin word for it was plumbum candidum , or "white lead". Stannum apparently came from an earlier stāgnum (meaning the same substance), the origin of the Romance and Celtic terms for tin , such as French étain , Spanish estaño , Italian stagno , and Irish stán . The origin of stannum / stāgnum is unknown; it may be pre- Indo-European . The Meyers Konversations-Lexikon suggests instead that stannum came from Cornish stean , and

3696-470: The fractured ends), divided by the original sectional area. It is sometimes stated that this is a more reliable indicator of the "ductility" than the elongation at failure (partly in recognition of the fact that the latter is dependent on the aspect ratio of the gauge length, although this dependence is far from being universally appreciated). There is something in this argument, but the RA is still some way from being

3773-439: The great majority of its compounds, tin has the oxidation state II or IV. Compounds containing bivalent tin are called stannous while those containing tetravalent tin are termed stannic . Halide compounds are known for both oxidation states. For Sn(IV), all four halides are well known: SnF 4 , SnCl 4 , SnBr 4 , and SnI 4 . The three heavier members are volatile molecular compounds, whereas

3850-414: The importance of the DBTT in selecting the correct material for a specific application. For example, zamak 3 exhibits good ductility at room temperature but shatters when impacted at sub-zero temperatures. DBTT is a very important consideration in selecting materials that are subjected to mechanical stresses. A similar phenomenon, the glass transition temperature , occurs with glasses and polymers, although

3927-451: The late 1970s and early 1980s, the U.S. reduced its strategic tin stockpile, partly to take advantage of historically high tin prices. The 1981–82 recession damaged the tin industry. Tin consumption declined dramatically. ITC was able to avoid truly steep declines through accelerated buying for its buffer stockpile; this activity required extensive borrowing. ITC continued to borrow until late 1985 when it reached its credit limit. Immediately,

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4004-409: The levels of carbon decreases ductility. Many plastics and amorphous solids , such as Play-Doh , are also malleable. The most ductile metal is platinum and the most malleable metal is gold . When highly stretched, such metals distort via formation, reorientation and migration of dislocations and crystal twins without noticeable hardening. The quantities commonly used to define ductility in

4081-460: The lowest in group 14, and boils at 2,602 °C (4,716 °F), the second lowest (ahead of lead ) in its group. The melting point is further lowered to 177.3 °C (351.1 °F) for 11 nm particles. β-tin, also called white tin , is the allotrope (structural form) of elemental tin that is stable at and above room temperature. It is metallic and malleable, and has body-centered tetragonal crystal structure. α-tin, or gray tin ,

4158-451: The market and mining technology. It is estimated that, at current consumption rates and technologies, the Earth will run out of mine-able tin in 40 years. In 2006 Lester Brown suggested tin could run out within 20 years based on conservative estimates of 2% annual growth. Scrap tin is an important source of the metal. Recovery of tin through recycling is increasing rapidly as of 2019. Whereas

4235-455: The material following a modification of the Griffith equation, where the critical fracture stress increases due to the plastic work required to extend the crack adding to the work necessary to form the crack - work corresponding to the increase in surface energy that results from the formation of an addition crack surface. The plastic deformation of ductile metals is important as it can be a sign of

4312-410: The mechanism is different in these amorphous materials . The DBTT is also dependent on the size of the grains within the metal, as typically smaller grain size leads to an increase in tensile strength, resulting in an increase in ductility and decrease in the DBTT. This increase in tensile strength is due to the smaller grain sizes resulting in grain boundary hardening occurring within the material, where

4389-402: The metal transitions from a brittle behavior to a ductile behavior, or from a ductile behavior to a brittle behavior, is known as the ductile-brittle transition temperature (DBTT). Below the DBTT, the material will not be able to plastically deform, and the crack propagation rate increases rapidly leading to the material undergoing brittle failure rapidly. Furthermore, DBTT is important since, once

4466-412: The most stable being tin-121m, with a half-life of 43.9 years. The relative differences in the abundances of tin's stable isotopes can be explained by how they are formed during stellar nucleosynthesis . Tin-116 through tin-120, along with tin-122, are formed in the s -process (slow neutron capture) in most stars which leads to them being the most common tin isotopes, while tin-124 is only formed in

4543-412: The neck at the point of fracture bears no direct relation to the raw number obtained from the nominal stress-strain curve; the true strain in the neck is often considerably higher. Also, the true stress at the point of fracture is usually higher than the apparent value according to the plot. The load often drops while the neck develops, but the sectional area in the neck is also dropping (more sharply), so

4620-469: The percent elongation at break, given by the equation: % E L = ( l f − l 0 l 0 ) × 100 {\displaystyle \%EL=\left({\frac {l_{f}-l_{0}}{l_{0}}}\right)\times 100} where l f {\displaystyle l_{f}} is the length of the material after fracture and l 0 {\displaystyle l_{0}}

4697-428: The potential failure of the metal. Yet, the point at which the material exhibits a ductile behavior versus a brittle behavior is not only dependent on the material itself but also on the temperature at which the stress is being applied to the material. The temperature where the material changes from brittle to ductile or vice versa is crucial for the design of load-bearing metallic products. The minimum temperature at which

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4774-609: The primary lodes. Tin is often recovered from granules washed downstream in the past and deposited in valleys or the sea. The most economical ways of mining tin are by dredging , hydraulicking , or open pits . Most of the world's tin is produced from placer deposits, which can contain as little as 0.015% tin. About 253,000 tonnes of tin were mined in 2011, mostly in China (110,000 t), Indonesia (51,000 t), Peru (34,600 t), Bolivia (20,700 t) and Brazil (12,000 t). Estimates of tin production have historically varied with

4851-414: The range of sample dimensions in common use is quite wide, it can lead to highly significant variations (by factors of up to 2 or 3) in ductility values obtained for the same material in different tests. A more meaningful representation of ductility would be obtained by identifying the strain at the onset of necking, which should be independent of sample dimensions. This point can be difficult to identify on

4928-472: The reaction of hydrochloric acid and tin produces SnCl 2 and hydrogen gas. Alternatively SnCl 4 and Sn combine to stannous chloride by a process called comproportionation : Tin can form many oxides, sulfides, and other chalcogenide derivatives. The dioxide SnO 2 (cassiterite) forms when tin is heated in the presence of air . SnO 2 is amphoteric , which means that it dissolves in both acidic and basic solutions. Stannates with

5005-456: The result of unintentional alloying due to trace metal content in the copper ore. The addition of a second metal to copper increases its hardness, lowers the melting temperature, and improves the casting process by producing a more fluid melt that cools to a denser, less spongy metal. This was an important innovation that allowed for the much more complex shapes cast in closed molds of the Bronze Age. Arsenical bronze objects appear first in

5082-427: The slightly more stable +4. Tin is the 49th most abundant element on Earth, making up 0.00022% of its crust, and with 10 stable isotopes, it has the largest number of stable isotopes in the periodic table, due to its magic number of protons. It has two main allotropes : at room temperature, the stable allotrope is β-tin, a silvery-white, malleable metal; at low temperatures it is less dense grey α-tin, which has

5159-586: The stable isotopes, tin-115 has a high neutron capture cross section for fast neutrons, at 30 barns . Tin-117 has a cross section of 2.3 barns, one order of magnitude smaller, while tin-119 has a slightly smaller cross section of 2.2 barns. Before these cross sections were well known, it was proposed to use tin-lead solder as a coolant for fast reactors because of its low melting point. Current studies are for lead or lead-bismuth reactor coolants because both heavy metals are nearly transparent to fast neutrons, with very low capture cross sections. In order to use

5236-678: The structure [ Sn(OH) 6 ] , like K 2 [ Sn(OH) 6 ], are also known, though the free stannic acid H 2 [ Sn(OH) 6 ] is unknown. Sulfides of tin exist in both the +2 and +4 oxidation states: tin(II) sulfide and tin(IV) sulfide ( mosaic gold ). Stannane ( SnH 4 ), with tin in the +4 oxidation state, is unstable. Organotin hydrides are however well known, e.g. tributyltin hydride (Sn(C 4 H 9 ) 3 H). These compounds release transient tributyl tin radicals, which are rare examples of compounds of tin(III). Organotin compounds, sometimes called stannanes, are chemical compounds with tin–carbon bonds. Of

5313-420: The tetrafluoride is polymeric. All four halides are known for Sn(II) also: SnF 2 , SnCl 2 , SnBr 2 , and SnI 2 . All are polymeric solids. Of these eight compounds, only the iodides are colored. Tin(II) chloride (also known as stannous chloride) is the most important commercial tin halide. Illustrating the routes to such compounds, chlorine reacts with tin metal to give SnCl 4 whereas

5390-523: The tetraorgano derivatives, are prepared by redistribution reactions : Divalent organotin compounds are uncommon, although more common than related divalent organogermanium and organosilicon compounds. The greater stabilization enjoyed by Sn(II) is attributed to the " inert pair effect ". Organotin(II) compounds include both stannylenes (formula: R 2 Sn, as seen for singlet carbenes ) and distannylenes (R 4 Sn 2 ), which are roughly equivalent to alkenes . Both classes exhibit unusual reactions. Tin

5467-588: The tin compounds, the organic derivatives are commercially the most useful. Some organotin compounds are highly toxic and have been used as biocides . The first organotin compound to be reported was diethyltin diiodide ((C 2 H 5 ) 2 SnI 2 ), reported by Edward Frankland in 1849. Most organotin compounds are colorless liquids or solids that are stable to air and water. They adopt tetrahedral geometry. Tetraalkyl- and tetraaryltin compounds can be prepared using Grignard reagents : The mixed halide-alkyls, which are more common and more important commercially than

5544-407: The transition is sharper than others and typically requires a temperature-sensitive deformation mechanism. For example, in materials with a body-centered cubic (bcc) lattice the DBTT is readily apparent, as the motion of screw dislocations is very temperature sensitive because the rearrangement of the dislocation core prior to slip requires thermal activation. This can be problematic for steels with

5621-465: The true stress there is rising. There is no simple way of estimating this value, since it depends on the geometry of the neck. While the true strain at fracture is a genuine indicator of "ductility", it cannot readily be obtained from a conventional tensile test. The Reduction in Area (RA) is defined as the decrease in sectional area at the neck (usually obtained by measurement of the diameter at one or both of

5698-586: The world's tin in 2007. Most of the world's tin is traded on LME, from 8 countries, under 17 brands. The International Tin Council was established in 1947 to control the price of tin. It collapsed in 1985. In 1984, the Association of Tin Producing Countries was created, with Australia, Bolivia, Indonesia, Malaysia, Nigeria, Thailand, and Zaire as members. Tin is unique among mineral commodities because of

5775-458: Was able to restrain the price during periods of high prices by selling from the stockpile. This was an anti-free-market approach, designed to assure a sufficient flow of tin to consumer countries and a profit for producer countries. However, the buffer stockpile was not sufficiently large, and during most of those 29 years tin prices rose, sometimes sharply, especially from 1973 through 1980 when rampant inflation plagued many world economies. During

5852-549: Was most likely the original source of tin. Other tin ores are less common sulfides such as stannite that require a more involved smelting process. Cassiterite often accumulates in alluvial channels as placer deposits because it is harder, heavier, and more chemically resistant than the accompanying granite . Cassiterite is usually black or dark in color, and these deposits can be easily seen in river banks . Alluvial ( placer ) deposits may incidentally have been collected and separated by methods similar to gold panning . In

5929-415: Was used in solder. The rest was divided between tin plating, tin chemicals, brass and bronze alloys, and niche uses. Pigment Yellow 38, tin(IV) sulfide , is known as mosaic gold . Purple of Cassius , Pigment Red 109, a hydrous double stannate of gold , was mainly, in terms of painting, restricted to miniatures due to its high cost. It was widely used to make cranberry glass . It has also been used in

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