Cavity growth and rupture of beta-treated zirconium: A crystallographic model

This study aims to understand the damage mechanisms observed in beta-treated zirconium. Damage voids are characterized by a tubular morphology with hexagonal cross-section; their growth kinetics is determined experimentally. From these observations, a model based on the principle of creation of free surface by crystallographic slip permits one to explain the stability of the hexagonal shape and to predict a growth rate closer to the experimental value than traditional models. This improvement is due to the sensitivity of the free surface creation mechanism to the stress concentration factor k, which cannot be accounted for in models based on continuum mechanics. Copyright (C) 1996 Acra Metallurgica Inc.