Age hardening and softening in cold-rolled Al-Mg-Mn alloys with up to 0.4wt%Cu

Description/Abstract

The age hardening and age softening of nine solution treated and subsequently cold-rolled Al-(1-3)Mg-(0-0.4)Cu-0.15Si-0.25Mn (in wt%) alloys with potential applications in both packaging and automotive industries have been investigated. Cold work levels were 10, 40 and 90% reduction. The proof strengths of the aged alloys range from 130 to 370MPa. A physically based model for yield strength has been developed which includes a one parameter dislocation evolution model to describe work hardening and recovery and a two precipitate precipitation hardening model. The model is based on analytical equations, avoiding computing time intensive iterative schemes. An exceptionally high model accuracy has been demonstrated. The model parameters are verified by transmission electron microscopy and calorimetry analysis of the materials.