Melting As An Extreme Deformation Mechanism At High Strain Rates
Free (open access)
273 - 282
L. E. Murr & C. Pizaña
Deformation, especially plastic deformation involving shock and impact in crystalline metal and alloy systems, begins as nonlinear dislocation phenomena which in the extreme deformation regime involving high strains and high-strainrates leads variously to shear phenomena involving twinning and microband formation, dynamic recrystallization either as localized shear instabilities in shear bands or large volume solid-state flow, and finally localized melting. These mechanisms can be viewed as \“deformation state” changes within some pressure-temperature regimes. In this work, we present examples of deformation-induced melting, especially in association with dynamic recrystallization (DRX). These examples include partial melting in explosive weld-wave vortex structures in connection with DRX in several dissimilar metal and alloy (explosive welded) systems, as well as projectile-target interactions for W single crystal rods and W rods clad with Inconel 718 (53% Ni, 17% Fe, 20% Cr) penetrating RHA steel targets at impact velocities ranging from 1.2 to 1.4 km/s. Keywords: dynamic recrystallization, melting, projectile-target interactions, shear bands, microstructures. 1 Introduction There are numerous examples of melting in deformation or melting especially as a consequence of extreme deformation. These include the so-called mach stem zones along the central axis of cylindrical shock regimes [1,2], melting zones
dynamic recrystallization, melting, projectile-target interactions,shear bands, microstructures.