Synchrotron X-ray topography has been used to study dislocation behavior ar
ound notches in single-crystals of ice during in-situ deformation at a cons
tant strain-rate. During deformation at - 8 degrees C a dislocation-deplete
d zone (DDZ) formed above the notch while a vertical array of dislocations
formed below the notch. Modeling the interaction between basal plane disloc
ation loops and the notch stress field suggested that this DDZ arose from d
islocations gliding completely through the specimen. Dislocation activity a
round the notch at -8 degrees C was much greater than that observed at -40
degrees C and -60 degrees C. (C) 2000 Elsevier Science B.V. All rights rese
rved.