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

Adiabatic shear bands self-organize themselves: this phenomenon was investi gated 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-ra te deformation (similar to 10(4) s(-1)). This method was used to examine th e shear-band initiation, propagation, as well as spatial distribution. The spacing of shear bands in the three materials varied widely and showed cons iderable differences during the initiation and propagation. Shear-band spac ing is compared with the theories proposed by Grady and Kipp (momentum diff usion), Wright and Ockendon (perturbation), and Molinari (perturbation plus work hardening). Additionally, the effect of microstructural inhomogeneiti es on initiation is discussed. A discontinuous growth mode for shear locali zation under periodic perturbation is proposed based on two-dimensional gro wth considerations, not incorporated into the one-dimensional perturbation and momentum diffusion theories.