Abstract
SUMMARY: The technique of combined electron microscopy and energy analysis is described, together with the main energy loss process that is used to analyse composition. It is shown that the spatial resolution of the technique is ∼ 14 nm which is ten times better than any other technique available at present. The composition resolution in aluminium alloys is < 1 at.%, the exact value depends upon which alloy system is used.Applications of the technique to the measurement of fine scale concentration gradients are described for Al‐Cu, Al‐Mg and Al‐Zn‐Mg alloys.