7068 aluminium alloy is one of the strongest commercially available aluminium alloys, with a tensile strength comparable to that of some steels. This material, also known as an aircraft alloy, is heat treatable. The main alloying elements are zinc (7.3 to 8.3%), magnesium (2.2 to 3.0%), copper (1.6 to 2.4%) and zirconium (0.05 to 0.15%), with traces of silicon, iron, manganese, chromium, and titanium.