Modelling the Effect of Room Temperature Storage and Deformation on the Age-hardening Behaviour of Al-Mg-Si alloys

The present investigation deals with modelling of the age-hardening behaviour of 6XXX series automotive sheet alloys. The basis for the work is a precipitation model developed for coupled nucleation, growth, dissolution and coarsening in Al-Mg-Si extrusion alloys. It has been advanced to incorporate the important effects of room temperature (RT) storage and deformation prior to the final age-hardening. The model predicts the evolution of the precipitate structure and the corresponding RT yield strength for non-isothermal heat treatments. The model validation is based on both a comprehensive set of tensile tests and TEM measurements on selected samples. A comparison between model predictions and measurements shows reasonable agreement, and it is concluded that after some further development, the model can be used as an industrial tool for process chain simulations of the yield strength response following complex heat treatments and deformation schedules.