Effect of titanium additions on mechanical properties of Al-Cu-Mg-Agalloy

The precipitation hardening response, microstructure and mechanical properties of four Al - Cu - Mg - Ag based alloys containing 0, 0(.)25, 0(.)6 and 1(.)1 (wt-%) titanium were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). It was shown that increasing the titanium content from 0 to 0(.)6 wt-% increased the tensile strength at all test temperatures up to 350degreesC. The high strength of the alloy with 0-6%Ti is attributed to the high density and high thermal stability of fine Q precipitates and an additional titanium containing intermetallic compound (Al3Ti).