|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Dynamic Behavior of Materials VIII
||Viscous Sliding Flow of Shear Bands in Metals
||Dinakar Sagapuram, Koushik Viswanathan
|On-Site Speaker (Planned)
Shear banding is a plastic flow instability that often acts as a precursor to failure in dynamic deformation of metals. We study shear band formation and flow localization in metals under high-rate deformation (104-105 /s) imposed by cutting using high-speed imaging, image analysis and micro-marker techniques. Quantitative information pertaining to localized shear band flow profiles in terms of strain, strain rate and displacements is presented. We show that shear bands form in two distinct phases: a rapid initiation phase, followed by a universal viscous-like sliding phase that accounts for the band growth. We analyze shear band growth as two Bingham fluids sheared across their interface. The model fits the experimental displacement profiles well and shows that shear band flows with a very small viscosity. We argue that phonon drag on dislocations is at the origin of fluid-like behavior of shear bands. The material systems studied include Ti and Ni-based alloys.
||Planned: Supplemental Proceedings volume