Dislocations in ice as revealed by etching

Abstract

The process of etching and replicating ice surfaces has been investigated. It has been shown that the process can be made selective for specific purposes by preparing the surface with a microtome and by varying the concentration of the etchant, thickness of the etchant, temperature and drying time. Replication of etch-pits in the form of whiskers was possible for both basal and non-basal dislocations, thereby directly establishing the correspondence of etch-pits to line defects. The technique was used to study the movement of non-basal dislocations under uniform and non-uniform stress fields. Grown-in defects and non-basal dislocations could be revealed by the method.Le processus d'attaque et de reproduction des surfaces de glace a \ue9t\ue9 \ue9tudi\ue9. Il a \ue9t\ue9 d\ue9montr\ue9 que ce processus peut \ueatre appliqu\ue9 pour fins particuli\ue8res en pr\ue9parant la surface \ue0 l'aide d'un microtome et en faisant varier la concentration et l'\ue9paisseur du corrosif caustique, la temp\ue9rature et le temps de s\ue9chage. Il a \ue9t\ue9 possible de reproduire les figures de corrosion sous forme de stries pour les dislocations sur les plans de base et autres, \ue9tabilissant ainsi directement le rapport entre les figures de corrosion et les d\ue9fauts de ligne. Cette technique a servi \ue0 \ue9tudier le mouvement des dislocations autres que sur le plan de base dans des champs de contraintes uniformes et non uniformes. Cette m\ue9thode permet de d\ue9celer les d\ue9fauts inh\ue9rents et les dislocations autres que sur le plan de base.Peer reviewed: YesNRC publication: Ye