Abstract
In situ transmission electron microscopy observations have been made in magnesium and beryllium of the glide process in the prismatic plane. The observations are in accordance with a jog-pair mechanism at high temperatures and a locking–unlocking cross-slip mechanism at low temperatures. Improved calculations of the corresponding activation energy and activation volume are reported which take full account of anisotropy. Agreement with the experimental values in Mg can only be reached when it is assumed that the jog in the glide process has twice the elementary height.
