MODELING DAMAGE OF AL-ZN-MG ALLOYS

The present work is concerned with the modelling of damage initiation and growth in Al-Zn-Mg alloys, and also with an estimation of the duct ility in uniaxial tension. An elastoplastic self-consistent model is d eveloped accounting for crystallographic texture and grain shape effec ts, which also integrates the voids formed by the damage process. The damage evolution is followed within this framework, allowing the predi ction of the macroscopic mechanical behavior, and particularly the str ess-strain curves for different tensile directions. A bifurcation anal ysis adapted for this anisotropic compressible case was developed and used to estimate the ductility. Effects of texture, grain shape and cr itical parameters for damage nucleation are investigated on a theoreti cal basis. The observed yield stress and fracture strain vs tensile an gle profiles observed experimentally can be predicted for certain case s.