Quantification of recrystallization kinetics in industrially processed 5xxx aluminum alloy sheet

The annealing kinetics of two aluminum alloys AA5xxx is investigated. The volume fraction of recrystallized material, Vv, is determined for a series of partly recrystallized samples both by hardness measurements and by electron back scattering diffraction (EBSD). Because of extended recovery overlapping with recrystallization, in particular in AA5182, it is not straightforward to estimate Vv from the hardness measurements. Two methods are suggested: one relying solely on the hardness data, and one in which EBSD data are used to estimate the hardness at the onset of recrystallization. Effects of the choice of method and of parameters on the resulting annealing kinetics are analysed, and the potential and limitations of the two methods are discussed.