Straining experiments were carried out in situ in a transmission electron microscope. Five different antiphase boundary energies were measured, and were compared with the corresponding densities of incorrect first-nearest neighbour atoms. The identification of a tension-compression asymmetry in pyramidal slip, and a detailed analysis of the corresponding microscopic mechanisms, confirmed the usefulness of such in situ studies. A comparison of the properties of the various slip systems showed that they were controlled by different microscopic mechanisms. None of them were covalent in origin.

In situ Observations of Unusual Dislocation Mechanisms in the Intermetallic Alloy, Ti3Al. M.Legros, D.Caillard: Journal of Microscopy, 2001, 203[1], 90-8