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

Abstract EN

The aim of the present work is to stud}- the effect of the cold deformation followed by heat treatment on the microstructure and the mechanical properties of an .■il-Mg-Si alloy.

Differential scanning calonmetry indicates that precipitation of the metastable 0'phase occurs in the temperature range (220-260 ’C) for the solution treated and then quenched alloy to room temperature The exploitation of the DOC curves by the Kissinger method has shown that the activation energj• value of the precipitation reaction is about S3.1 kj/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 CX-aiuminium 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.