Effect of Low Degree Cold Deformation on Hardening During Artificial Aging of Sheets Made from Alloys of the Al – Mg – Si System

The article examines the poorly studied effect of reducing the strength properties of artificially aged aluminum sheets made of Al – Mg – Si alloys preliminarily subjected to plastic deformation. Specimens of cold-rolled strip made of alloy 6022 obtained in industrial production were investigated. To assess the magnitude of deformations occurring during sheet stamping of car structural parts, the processes of forming the C- and D-pillars, the inner parts of the hood and the tray were modeled using the PAM-Stamp 2G software package. Quenching, stabilizing heat treatment, deformation, and artificial aging were performed under laboratory conditions. The mechanical properties of the alloy were determined during tensile testing of flat specimens. Transmission electron microscopy was used to investigate the microstructure of the alloy. Thermal hardening was found to slow down after stabilizing heat treatment and deformation. This effect is explained by the fact that the Mg – Si clusters formed in the course of stabilizing heat treatment are destroyed during deformation. As a result, artificial aging in the samples begins at an earlier stage of thermal hardening.