Friction stir welding of titanium alloy TiAl6V4 to aluminium alloy AA2024-T3

Titanium alloy TiAl6V4 and aluminium alloy 2024-T3 were successfully joined by friction stir welding. Microstructure, hardness and tensile strength of the butt joint were investigated. The weld nugget exhibits a mixture of fine recrystallized grains of aluminium alloy and titanium particles. Hardness profile reveals a sharp decrease at titanium/aluminium interface and evidence of microstructural changes due to welding on the aluminium side. The ultimate tensile strength of the joint reached 73% of AA2024-T3 base material strength.