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.