Effet de vieillissement naturel et artificiel sur les propriétés mécaniques de deux tôles AlMgSi

Abstract

In this work, we have undertaken the study of two sheets AlMgSi alloys (6XXX series). Which have a great interest for their privileged uses in automotive and aeronautical industries. The aim of the present work is the study of the phase’s transformation reactions and the effect of natural and artificial ageing on the mechanical properties of the studies AlMgSi alloys. For the characterization of these materials, we have used various experimental techniques such as optical microscopy, X-ray diffraction, microhardness measurements and differential calorimetric analysis (DSC). The characterization by diffraction of X-ray did not highlight the presence of another phase in addition to the matrix α-aluminum. The non detection of another phase could be due to its small volume fraction. It revealed the presence of anisotropy, as the sheets have been cold and hot rolled, during the fabrication. The microstructure of alloys has been characterized by optical microscopy that confirms a significant presence of thermally stable precipitates. Micro-hardness measurements show that if excess improves the mechanical properties of Al-Mg-Si alloys. The differential scanning calorimetry study allowed us to follow the sequence of precipitation phase transformations in the studied alloys.