Self-organization of shear bands in Ti, Ti-6%Al-4%V, and 304 stainless steel

Abstract
Adiabatic shear bands self-organize themselves : this phenomenon was investigated in three different alloys ( stainless steel 304L, Ti, and Ti-6%Al-%V) through the radial collapse of a thick-walled cylinder under high-strain-rate deformation ( ≈ 10⁴s^-1>). This method was used to examine the shear-band initiation, propagation, as well as spatial distribution. The spacing of shear bands in the three materials varied widely and showed considerable differences during the initiation and propagation. Shear-band spacing is compared with the theories proposed by Grady and Kipp (momentum diffusion), Wright and Ockendon (perturbation), and Molinari (perturbation plus work hardening). Additionally, the effect of microstructural inhomogeneities on initiation is discussed. A discontinuous growth mode for shear localization under periodic perturbation is proposed based on two-dimensional growth considerations, not incorporated into the one-dimensional perturbation and momentum diffusion theories.