Microstructural features of flow

Cylindrical specimens of commercial pure titanium have been compressed at strain rates in the range of 0.1 to 100 s-1 and temperatures in the range of 25°C to 400°C. At strain rates of 10 and 100 s-1, the specimens exhibited adiabatic shear bands. At lower strain rates, the material deformed in an inhomogeneous fashion. These material-related instabilities are examined in the light of the "phenomenological model" and the "dynamic materials mode". It is found that the regime of adiabatic shear band formation is predicted by the phenomenological model, while the dynamic materials model is able to predict the inhomogeneous deformation zone. The cri-terion based on power partitioning is competent to predict the variations within the inhomo-geneous deformation zone