The annealing behaviour of deformed cube-oriented aluminium single crystals

Single crystals of the {001}〈100〉 cube orientation of a dilute single-phase Al–Si alloy have been deformed in plane strain compression at temperatures between 300 and 500°C at strain rates between 0.5 and 50/s. The stability of the cube orientation was found to be dependent on the deformation conditions, which is in agreement with previous work. The deformed crystals contained bands of subgrains of a range of sizes and misorientations. Detailed EBSD analysis of deformed and annealed crystals revealed a strong correlation between subgrain growth and misorientation, and analysis of the data enabled the mobility of low angle grain boundaries in the misorientation range 5–20° to be determined in the temperature range 300–450°C. It was found that the boundary mobility increased with increasing misorientation up to ∼15–20° and thereafter reached a plateau. The activation energies of migration were consistent with control by lattice diffusion of Si in Al and the activation energy was found to increase with increasing misorientation.