Damage evolution model for particle reinforced aluminum matrix composite

Particle reinforced aluminum matrix composite was inevitably damaged when plastic deformation occurred and it eventually led to the macro fracture. A damage evolution model was established to study the evolution of damage for composite during hot deformation process based on the theory of continued damage mechanics. Zener-Hollomon parameter which contained temperature and strain rate was taken into the model. Damage evolution curves of composite were obtained in different deformation conditions by high temperature multi-step tensile test referring to the elastic modulus method proposed by Lemaitre. The parameter of the model was determined as A(Z)=2.22769-0.09438lnZ+0.00238ln2, Z by damage evolution curves data fitting. The judgment of macro fracture of composite was determined as DC(Z)=0.50915-0.00577lnZ by the damage critical value fitting. The occurrence of macro fracture could be judged by comparing the current damage value and the damage critical value. The model was verified by high temperature compression test. The results showed that the model could better predict the macro fracture of composite and provided a theoretical basis for actual production process. ©, 2015, Editorial Office of Chinese Journal of Rare Metals. All right reserved.