Development of adiabatic shear bands in annealed 316L stainless steel: Part I. Correlation between evolving microstructure and mechanical behavior

摘要

Adiabatic shear localization in an annealed AISI 316L stainless steel was examined through a forced shear technique using a split Hopkinson pressure bar and hat-shaped specimens. A well-controlled forced shear technique provided the possibility of correlating the microstructural evolution of adiabatic shear localization to its transient mechanical behavior. The initiation of adiabatic shear bands occurred when the shear stress peaked after substantial work hardening. The work-hardening rate was found to play a dominant role in the formation of adiabatic shear localization. The stress drop presupposed the development of the localized deformation. A core structure of shear bands was generated within the shear band, which characterized a narrow-down process in the early stage of the shear band evolution. The continuous expansion of the shear band core to the entire width of the band was seen to correlate with the full development of shear localization.