Information AboutTitanium |
Titanium is a Chemical Element in the Periodic Table that has the symbol '''Ti''' and Atomic Number 22. It is a light, strong, lustrous, Corrosion -resistant (including resistance to Sea Water and Chlorine ) Transition Metal with a white-silvery-metallic Colour . Titanium is used in strong light-weight Alloy s (most notably with Iron and Aluminium ) and its most common compound, Titanium Dioxide , is used in white pigments. Examples in which white pigment, consisting of titanium oxide, is used, are Correction Fluid and commonly used white paint to repaint walls. It is also used in toothpaste and the white road marking paints. Substances containing titanium are called titaniferous. The element occurs in numerous minerals with the main sources being Rutile and Ilmenite , which are widely distributed over the Earth . There are two Allotropic forms and five naturally occurring Isotope s of this element; titanium-46 through titanium-50 with titanium-48 being the most Abundant (73.8%). One of titanium's most notable characteristics is that it is as strong as Steel but is only 60% its density. Titanium's properties are chemically and physically similar to Zirconium . Notable characteristics Titanium is well known for its excellent Corrosion resistance (almost as resistant as Platinum ), being able to withstand attack by Acid s, moist Chlorine gas, and by common Salt solutions. Pure titanium is not Soluble in water but is soluble in concentrated acids. A Metallic Element , it is also well-known for its high strength-to-weight ratio. It is a light, strong metal with low Density (60% as dense as Steel ) that, when pure, is quite Ductile (especially in an Oxygen -free environment), easy to work, lustrous, and metallic-white in Colour . The relatively high Melting Point of this element makes it useful as a Refractory Metal . Titanium is as strong as steel, but 43% lighter; it is 60% heavier than Aluminium , but twice as strong; however these numbers can vary a little because of the use of different alloys. These properties make titanium very resistant to the usual kinds of Metal Fatigue .
Experiments have shown that natural titanium becomes very Radioactive after it is bombarded with Deuteron s, emitting mainly Positron s and hard Gamma Ray s. The metal is a dimorphic Allotrope with the hexagonal alpha form changing into the cubic beta form very slowly at around 880 °C . When it is red hot the metal combines with oxygen, and when it reaches 550 °C it combines with Chlorine . It also reacts with the other Halogen s and absorbs Hydrogen . Applications Approximately 95% of titanium production is consumed in the form of Titanium Dioxide (Ti O 2), an intensely white permanent Pigment with good covering power in Paint s, Paper , Toothpaste , and Plastics . Paints made with titanium dioxide are excellent reflectors of Infrared Radiation and are therefore used extensively by Astronomer s and in exterior paints. It is also used in Cement , in Gemstone s, and as a strengthening filler in Paper . Recently, it has been put to use in air purifiers (as a filter coating) or in window film on buildings which when exposed to UV light (either solar or man-made) and moisture content in the air converts unfiltered air pollution into Hydroxyl Radicals . Because of its very high Tensile Strength (even at high temperatures), light weight, extraordinary corrosion resistance, and ability to withstand extreme temperatures, titanium Alloy s are principally used in Aircraft , Armour Plating , Naval ships, Spacecraft and Missile s. It is used in Steel alloys to reduce grain size and as a deoxidizer but in Stainless Steel it is employed to reduce Carbon content. Titanium is often alloyed with Aluminium (to refine grain size), Vanadium , Copper (to harden), Iron , Manganese , Molybdenum and with other metals. Welded Titanium pipe is used in the chemical industry for its corrosion resistance and is seeing growing use in petroleum drilling especially offshore for its strength, light weight and corrosion resistance. When alloyed with vanadium, it is used to make the outer skin of aircraft, fire walls, Landing Gear , and hydraulic tubing. Titanium Metals Corporation's Annual Report of 2004 estimates titanium content of modern airliners to be 58, 43, and 18 Tonne s for the Boeing 777, 747 and 737 respectively. While for the Airbus, 24, 17 and 12 tonnes of titanium are used for the A340, A330 and A320 respectively. Generally, newer models use more and widebodies use the most. For the newest models, the 787 might use 91 tonnes and the A380 77 tonnes. The engines account for 10-11 tonnes of those totals. Use of titanium in consumer products such as Tennis Racquet s, Golf Clubs , Bicycle s, Laboratory Equipment , Wedding Band s, and Laptop Computer s is becoming more common. Other uses:
Titanium has occasionally been used in construction: the 150-foot (45 m) memorial to Yuri Gagarin , the first man to travel in space, in Moscow , is made of titanium for the metal's attractive colour and association with rocketry. The Guggenheim Museum Bilbao and the Cerritos Library were the first buildings, respectively, in Europe and North America to be sheathed in titanium panels. History Titanium ( Latin '' Titans '', Earth or the first sons of Gaia ) was Discovered in England by Reverend William Gregor in 1791. He recognized the presence of a new element in Ilmenite , and named it ''menachite''. At around the same time, Franz Joseph Muller also produced a similar substance, but could not identify it. The element was independently rediscovered several years later by German chemist Martin Heinrich Klaproth in Rutile ore. Klaproth confirmed it as a new element and in 1795 he named it for the Latin word for Earth (also the name for the Titans of Greek Mythology ). The metal has always been difficult to extract from its various ores. Pure metallic titanium (99.9%) was first prepared in 1910 by Matthew A. Hunter by heating Ti Cl 4 with Sodium in a steel bomb at 700–800 °C in the Hunter Process . Titanium metal was not used outside the laboratory until 1946 when William Justin Kroll proved that titanium could be commercially produced by reducing Titanium Tetrachloride with Magnesium in the Kroll Process which is the method still used today. In 1950 – 1960 s the Soviet Union attempted to corner the world titanium market as a tactic in the Cold War to prevent the American military from utilizing it. In spite of these efforts, the U.S. obtained large quantities of titanium when a European company set up a front for the U.S. foreign intelligence agencies to purchase it. Indeed, titanium for the highly successful U.S. SR-71 Reconnaissance Aircraft was acquired from the Soviet Union at the height of the Cold War. Occurrence Titanium metal is not found unbound to other elements in nature but the element is the ninth most abundant element in the Earth 's crust (0.63% by Mass ) and is present in most Igneous Rock s and in Sediments derived from them (as well as in living things and natural bodies of water). It is widely distributed and occurs primarily in the Mineral s Anatase , Brookite , Ilmenite , Perovskite , Rutile , Titanite (sphene), as well in many Iron ores. Of these minerals, only ilmenite and rutile have significant economic importance, yet even they are difficult to find in high concentrations. Because it Reacts easily with Oxygen and Carbon at high temperatures it is difficult to prepare pure titanium Metal , Crystal s, or Powder . Significant titanium ore deposits are in Australia , Scandinavia , North America and Malaysia . ''See also .'' ''Chiffres de 2003, en milliers de tonnes de dioxide de titane'' ''Source ; L'état du monde 2005, annuaire économique géopolique mondial'' This metal is found in Meteorite s and has been detected in the Sun and in M-type Star s. Rock s brought back from the Moon during the Apollo 17 mission are composed of 12.1% TiO2. Titanium is also found in Coal ash, Plant s, and even the Human body. Isolation Because the metal reacts with air at high temperatures it can not be produced by reduction of its dioxide. Titanium metal is therefore produced commercially by the Kroll Process ; a complex, and expensive Batch Process developed in 1946 by William Justin Kroll . In the Kroll process, the oxide is first converted to chloride through Carbochlorination , whereby Chlorine gas is passed over red-hot Rutile or Ilmenite in the presence of Carbon to make TiCl4 . This is condensed and purified by Fractional Distillation and then Reduced with 800 °C molten Magnesium in an Argon atmosphere. A newer process called the FFC Cambridge Process may displace this older process. This method uses the feedstock Titanium Dioxide powder (which is a refined form of Rutile ) to make the end product which is either a powder or sponge. If mixed oxide powders are used, the product is an alloy at a much lower cost than the conventional multi-step melting process. It is hoped that the FFC Cambridge Process will render titanium a less rare and expensive material for the Aerospace industry and the luxury goods market, and will be seen in many products currently manufactured using Aluminium and specialist grades of Steel . Titanium may be purified to ultra high purity in small quantities by the Van Arkel DeBoer Process by reacting with iodine and decomposing the formed vapors over a hot filament to pure metal. Titanium Oxide is produced commercially by grinding its mineral ore and mixing it with Potassium Carbonate and aqueous Hydrofluoric Acid . This yields Potassium Fluorotitanate ( K 2Ti F 6) which is extracted with hot water and decomposed with Ammonia , producing an ammoniacal Hydrate d oxide. This in turn is ignited in a Platinum vessel, which creates pure titanium dioxide. Common titanium Alloy s are made by Reduction . For example; cuprotitanium (rutile with Copper added is reduced), ferrocarbon titanium (ilmenite reduced with Coke in an electric furnace), and manganotitanium (rutile with manganese or manganese oxides) are reduced. Compounds The +4 in the +3 Oxidation State are also common. Because of this high oxidation state, many titanium compounds have a high degree of Covalent Bond ing. Although titanium metal is relatively uncommon, due to the cost of extraction, s Anatase , Brookite , and Rutile . Paint made with titanium dioxide does well in severe temperatures, is somewhat self-cleaning, and stands up to marine environments. Pure titanium dioxide has a very high Index Of Refraction and an Optical Dispersion higher than Diamond . Star Sapphire s and Rubies get their Asterism from the titanium dioxide present in them. Titanate s are compounds made with titanium dioxide. Barium Titanate has Piezoelectric properties, thus making it possible to use it as a transducer in the interconversion of Sound and Electricity . Ester s of titanium are formed by the reaction of Alcohol s and titanium tetrachloride and are used to waterproof Fabric s. Titanium Nitride is often used to coat cutting tools, such as Drill Bit s. It also finds use as a gold-coloured decorative finish, and as a Barrier Metal in Semiconductor Fabrication . Titanium(IV) Chloride (titanium tetrachloride, TiCl4, sometimes called "Tickle") is a colourless, weakly Acid ic liquid which is used as an intermediate in the manufacture of titanium(IV) oxide for paint. It is widely used in Organic Chemistry as a Lewis Acid , for example in the Mukaiyama Aldol condensation. Titanium also forms a lower chloride, Titanium(III) Chloride (TiCl3), which is used as a Reducing Agent . Titanocene Dichloride is an important catalyst for carbon-carbon bond formation. Titanium Isopropoxide is used for Sharpless Epoxidation . Other compounds include; Titanium Bromide (used in metallurgy, Superalloy s, and high-temperature electrical wiring and coatings) and Titanium Carbide (found in high-temperature cutting tools and coatings).
Isotopes Naturally occurring titanium is composed of 5 stable Isotope s; 46Ti, 47Ti, 48Ti, 49Ti and 50Ti with 48Ti being the most abundant (73.8% Natural Abundance ). Eleven Radioisotope s have been characterized with the most stable being 44Ti with a Half-life of 63 years, 45Ti with a half-life of 184.8 minutes, 51Ti with a half-life of 5.76 minutes, and 52Ti with a half-life of 1.7 minutes. All of the remaining Radioactive isotopes have half-lifes that are less than 33 seconds and the majority of these have half-lifes that are less than half a second. The isotopes of titanium range in Atomic Weight from 39.99 Amu (40Ti) to 57.966 amu (58Ti). The primary Decay Mode before the most abundant stable isotope, 48Ti, is Electron Capture and the primary mode after is Beta Emission . The primary Decay Product s before 48Ti are element 21 ( Scandium ) isotopes and the primary products after are element 23 ( Vanadium ) isotopes. Precautions As a powder or in the form of metal shavings, titanium metal poses a significant fire hazard and, when heated in Air , an explosion hazard. Water and Carbon Dioxide -based methods to extinguish fires are ineffective on burning titanium; Class D dry powder fire fighting agents must be used instead. Salt s of titanium are often considered to be relatively harmless but its chlorine compounds, such as TiCl2, TiCl3 and TiCl4, have unusual hazards. The dichloride takes the form of pyrophoric black crystals, and the tetrachloride is a volatile fuming liquid. All of titanium's chlorides are Corrosive . Titanium also has a tendency to Bio-accumulate in tissues that contain Silica but it does not play any known biological role in Human s. See also References
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