A microstructure-based model for superplastic deformation and damage in magnesium alloys

The need to produce fuel efficient vehicles and reduced emissions has led the automotive industries to the use of the lightweight materials. The use of magnesium alloys through superplastic forming is very promising for this goal while it makes the manufacturing part less complex and reduces the weight of the parts extensively. Aside to their strength and ductility, magnesium alloys still need a major improvement to be studied before they can be considered as lightweight materials in automotive industries. That improvement is in fact developing the best thermo-mechanical processing approach considering several aspects of the microstructure and modeling and optimization of the deformation process. The objective of this study is to establish such a constitutive model and using this model to effectively obtain the optimum loading path and processing temperature to avoid local thinning and rupture of the material. This constitutive model integrates the effects of microstructural dynamics and their evolution with other continuum properties such as flow rule, hardening, temperature and strain rate.