Thermal aging, kinetics and mechanical properties of Al-7 wt% Mg alloy

• The kinetics of precipitation is very fast in Al-7%Mg alloy.
• The activation energy of discontinuous precipitation (Ea = 53.93 kJ/mol).
• The Avrami coefficient characterizes the transformation mechanism is determined (n = 1.87).

This work presents the experimental results of the differential scanning calorimetry (DSC), hardness measurements (Hv) and X-ray diffraction (XRD) analysis, investigating the kinetics of precipitation phenomena in Al-7 wt % Mg alloy. In the XRD and DSC curves indicates the formation of the intermediate precipitation of β-(Al3Mg2) phase respectively. The activation energies associated with the processes have been determined according to the three models proposed by Kissinger, Ozawa and Boswell. Consequently, the nucleation mechanism of the precipitates can be explained. These phases are confirmed by the XRD analysis.