Titanium is a metallicelement which is well known for its excellent corrosion resistance (almost as resistant as platinum) and for its high strength-to-weight ratio. It is a light, strong, easily fabricated metal with low density (40% as dense as steel) that, when pure, is quite ductile, easy to work, lustrous, and metallic-white in color. The relatively high melting point of this element makes it useful as a refractory metal. Titanium is as strong as steel, but 45% lighter; it is 60% heavier than aluminium, but twice as strong. These properties make titanium very resistant to the usual kinds of metal fatigue.
This metal forms a passive oxide coating when exposed to air but when it is in an oxygen-free environment it is ductile. The metal, which burns when heated in air, is also the only element that can burn in pure nitrogen gas. Titanium is resistant to dilute sulfuric and hydrochloric acid, along with chlorine gas, chloride solutions, and most organic acids.
Experiments have shown that natural titanium becomes very radioactive after it is bombarded with deuterons, emitting mainly positrons and hard gamma rays. The metal is dimorphic 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.
Because of its strength, light weight, extraordinary corrosion resistance, and ability to withstand extreme temperatures, titanium alloys are principally used in aircraft and missiles, although applications in consumer products such as golf clubs, bicycles, wedding bands, and laptop computers are becoming more common. Titanium is often alloyed with aluminum, iron, manganese, molybdenum and with other metals. Other uses;
Due to excellent resistance to sea water, it is used to make propeller shafts and rigging.
It is used to produce relatively soft artificial gemstones.
Titanium tetrachloride (TiCl4), a colorless liquid, is used to iridize glass and because it fumes strongly in moist air it is also used to make smoke screens.
In addition to being a very important pigment, titanium dioxide is also used in sunscreens due to its ability to protect skin by itself.
Because it is considered to be physiologically inert, the metal is used in joint replacement implants such as hip ball and sockets.
Its inertness and ability to be attractively colored makes it a popular metal for use in body piercing.
A potential use of titanium is in desalination plants.
Pure metallic titanium (99.9%) was first prepared in 1910 by Matthew A. Hunter by heating TiCl4 with sodium in a steel bomb at 700-800°C.
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 (which is the method still used today).
This metal is found in meteorites and has been detected in the sun and in M-type stars. Rockss brought back from the moon during the Apollo 17 mission are composed of 12.1% TiO2. Titanium is also found in coal ash, plants, and even the human body.
Titanium metal is produced commercially by reducing TiCl4 with magnesium, a process developed in 1946 by William Justin Kroll. This is a complex and expensive batch process, but a newer process called the "FFC-Cambridge" method 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 a continuous stream of molten titanium suitable for immediate use in the manufacture of commercial alloys.
It is hoped that the FFC-Cambridge method 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 aluminum and specialist grades of steel.
Naturally occurring titanium is composed of 5 stable isotopes; Ti-46, Ti-47, Ti-48, Ti-49 and Ti-50 with Ti-48 being the most abundant (73.8% natural abundance). 11 radioisotopes have been characterized with the most stable being Ti-44 with a half-life of 63 years, Ti-45 with a half-life of 184.8 minutes, Ti-51 with a half-life of 5.76 minutes, and Ti-52 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 (Ti-40) to 57.966 amu (Ti-58). The primary decay mode before the most abundant stable isotope, Ti-48, is electron capture and the primary mode after is beta emission. The primary decay products before Ti-48 are element 21 (scandium) isotopes and the primary products after are element 23 (vanadium) isotopes.
