Perturbation analysis of shear strain localization in rate sensitive materials

The localization of deformation into a shear band is discussed for rate dependent plastic materials. A shear layer model is proposed and the assumption is made that the material considered exhibits strain softening behavior in shear. The results of the shear layer model show that even small material rate sensitivity retards significantly the localization process. A linearized perturbation analysis underestimates the excess strain in the band, but it does provide a qualitative description of strain localization.