6061 T-6 is a precipitation hardening aluminum alloy containing magnesium and silicon as its major alloying elements. 6061 has good machinability and good weldability. Typically, after welding, the properties near the weld are those of 6061-0, a loss of strength of around 80%. The material can be re-heat-treated to restore -T4 or -T6 temper for the whole piece. After welding, the material can naturally age and restore some of its strength. 6061 is one of the most common alloys of aluminum for general purpose use. It is commonly used for construction of aircraft structures, such as wings and fuselages, bicycle frames, boat building and a wide range of automotive parts.