Characteristic

Hafnium is a chemical element with the symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals.

Phase at STP：solid

Appearance：steel gray

Melting point：2506 K (2233 °C, 4051 °F)

Boiling point：4876 K (4603 °C, 8317 °F)

Density (near r.t.)：13.31 g/cm³

when liquid (at m.p.)：12 g/cm³

Heat of fusion：27.2 kJ/mol

Heat of vaporization：648 kJ/mol

Molar heat capacity：25.73 J/(mol·K)

Application

Hafnium is used in filaments and electrodes. Some semiconductor fabrication processes use its oxide for integrated circuits at 45 nm and smaller feature lengths. Some superalloys used for special applications contain hafnium in combination with niobium, titanium, or tungsten.

Hafnium_MSDS.pdf