Processing of aluminium alloys containing titanium addition by mechanical alloying

In this work, mechanical alloying was used to produce precursor powders of 2024 and 7050 aluminium alloys containing titanium addition. Milling was performed in a planetary mill using a ball to powder weight ratio of 20:1 and a milling time varying from 10 to 100 h. Characterisation of the milled powders was performed by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and transmission electron microscopy (TEM). The results show, after 60 h of milling, the formation of a solid solution with a nanocrystalline structure with grain size ranging between 50 and 100 nm. DSC results show the temperatures of intermetallic precipitation, which were identified by XRD. The results confirm the possibility of using the mechanical alloying process to produce precursor powders able to develop a dispersion hardened aluminium alloy in a subsequent consolidation process.