Titanium (Ti) is a silver to grey-white, lustrous transition metal. The element was discovered in 1791 by William Gregor and was named by Martin Klaproth after the Titans of Greek mythology. In the earth’s crust it is the 9^th most frequent element and mostly present in the form of titanium oxides, with rutile (TiO₂) and ilmenite (FeTiO₃) being of most economic importance.

With its low density and simultaneous high strength, titanium is the element with the highest strength-to-density ratio. Due to its low density of 4.51 g/cm³, it is considered a light metal. Titanium has a high melting point of 1650 °C, is paramagnetic and has relatively low thermal and electrical conductivity. Below 0.49 K it becomes superconducting. When exposed to air, it readily oxides and forms a protective layer. This passive oxide coating gives it excellent resistance to corrosion, that is only compromised by concentrated acids. Its properties make it frequently used for lightweight cooking ware for camping or when alloyed with iron, aluminium, vanadium and molybdenum for aerospace, automotive, medical prostheses, jewellery, mobile phones and other applications.

When nitrified to TiN, i.e. in a reactive sputtering process, it exhibits a very high hardness and good thermal/ electrical conductivity, paired with a high melting point. This makes it widely applied in hard coatings for cutting tools. Depending of the discrete application, titanium can be alloyed with Al, Cr, W, Si, Ta and Nb to further modify the chemical and physical properties.

TiC is a very hard (Mohs hardness 9-9.5) refractory ceramic material with very good electrical conductivity and a positive temperature coefficient. In air it is stable up to 800°C. Among other things, TiC is used as a wear-resistant coating material for inserts, saw blades, etc.