Phenomenological model for superplastic deformation of Ti-6Al-4V

A phenomenological model based on three stage description of stress strain curves is suggested. The three distinct regions correspond to stable, quasi-stable strain hardening, and quasi-stable strain softening stages. Each stage is further characterized by a Zener-Hollomon type relationship and the typical values of various parameters and constants are determined from the experimental data on superplastic deformation of Ti-6Al-4V. The predictions of the model are in agreement with the experimental data up to large strains characteristics of superplastic deformation.