Measurements of subgrain growth in a single-phase aluminum alloy by high-resolution EBSD

Single crystals of {100}〈100〉 and {110}〈100〉 orientations of a high-purity Al–0.05% Si single-phase aluminum alloy have been deformed under plane strain compression at elevated temperatures. The deformed crystals of the {100}〈100〉 orientation contained bands of subgrains of a range of size and misorientation, whereas the {110}〈100〉 crystals gave very uniform microstructures. The specimens were annealed at temperatures between 300 and 450 °C and measurements of the subgrain growth have been made using high-resolution electron backscattered diffraction (EBSD) in a field emission gun scanning electron microscope (FEGSEM). Detailed analysis of deformed and annealed crystals revealed a strong correlation between subgrain growth and misorientation, and the analysis of the data enabled the mobility of low-angle boundaries and activation energies in the misorientation range of 2–20° to be determined.