CAVITY GROWTH AND RUPTURE OF BETA-TREATED ZIRCONIUM - A CRYSTALLOGRAPHIC MODEL

This study aims to understand the damage mechanisms observed in beta-t reated zirconium. Damage voids are characterized by a tubular morpholo gy with hexagonal cross-section; their growth kinetics is determined e xperimentally. From these observations, a model based on the principle of creation of free surface by crystallographic slip permits one to e xplain the stability of the hexagonal shape and to predict a growth ra te closer to the experimental value than traditional models. This impr ovement is due to the sensitivity of the free surface creation mechani sm to the stress concentration factor k, which cannot be accounted for in models based on continuum mechanics. Copyright (C) 1996 Acra Metal lurgica Inc.