Influence of cold deformation on the aging behavior of the Al-Mg-Si alloy

Abstract

the aim of the present work is to study the effect of the cold deformation followed by heat treatment on the
microstructure and the mechanical properties of an Al-Mg-Si alloy. Differential scanning calorimetry indicates that
precipitation of the metastable β
" phase occurs in the temperature range (220-260 °C) for the solution treated and then
quenched alloy to room temperature. The exploitation of the DSC curves by the Kissinger method has shown that the
activation energy value of the precipitation reaction is about 83.1 k J / mol. The amount of 30% cold deformation before
aging indicates that the first dissolution reaction at about 50°C and the precipitation temperature is around 240 °C.
Microstructural studies, of the aged cold-deformed sample, revealed the presence of fine precipitates embedded in the
aluminium matrix. At as quenched state of the alloy reveals an aging response. The increase of the microhardness with
the decrease of the elongation is mainly due to the severe strengthening by deformation, and not to the effect of
precipitation hardening.