Microanalysis across grain boundaries in aluminium alloys

Abstract
Solute concentration profiles have been measured across grain boundaries in aged Al-4-1 wt%Cu and Al-5-9 wt%Zn-3-2 wt%Mg alloys using the microanaly-tical techniques of combined electron microscopy/electron energy analysis (EMEA) and combined electron microscopy/X-ray microanalysis (EMMA). Agreement between the two techniques is good, provided sufficiently wide solute-depleted zones are developed to compensate for the relatively coarse spatial resolution of EMMA.