Effects of T9I6 thermo-mechanical process on microstructure, mechanical properties and ballistic resistance of 2519A aluminum alloy

The effects of T9I6 thermo-mechanical process on microstructures, mechanical properties and ballistic resistance of 2519A aluminum alloy were investigated by optical microscopy (OM), transmission electron microscopy (TEM), tensile tests and ballistic resistance test. After T9I6 treatment, the yield strength, tensile strength and elongation rate of 2519A aluminum alloy reach 501 MPa, 540 MPa and 14%, respectively. And the ballistic limit velocity of 2519A-T9I6 alloy (30 mm in thickness) is 715 m/s. The microstructure varies near the sidewalls of crater. The interrupted ageing contributes to these excellent properties of the alloy. During T9I6 process, the precipitation of Guinier Preston (GP) zone is finer and denser during the interrupted ageing, thus resulting in well precipitated strengthening phase.