Titanium

A silvery-coloured, strong but light metal element with the symbol Ti.

Titanium is a light, strong and corrosion-resistant transition metal. Its low density (60% as dense as steel) and ductility make it easy to work. Titanium is as strong as steel, but 43% lighter. Although it is 60% heavier than aluminium, it is twice as strong. Owing to its high strength-to-weight ratio and corrosion-resistance, it is used to make strong, light-weight alloys, usually by alloying with aluminium and vanadium, for use in aerospace and other critical applications.

Titanium forms a wide range of colourful, passive and protective oxide coatings when exposed to air at elevated temperatures but at room temperatures it resists tarnishing. The metal, which burns when heated in air 610°C or higher (forming titanium dioxide), is one of the few elements that will burn in pure nitrogen gas (at 800°C, forming titanium nitride). It is paramagnetic (weakly attracted to magnets) and has a very low electrical and thermal conductivity.

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 hot the metal will absorb nitrogen, hydrogen and oxygen.

Discovered in 1871 by the Reverend William Gregor and named after the Titans, the sons of the Earth goddess Gaea, in Greek and Roman mythology.