Apparent grain growth behavior of submicrometer grained Al-3 pct Mg during static annealing after fabrication by severe plastic straining

Recently, much research has been performed on the fabrication of bulk, porosity-free metals and alloys having a submicrometer grained (SMG) microstructure by imposing severe plastic straining. Concurrently, much attention has been paid to the microstructural stability of SMG materials against thermal exposure, because these materials possess a strong potential for high-strain-rate and/or low-temperature superplasticity. As a result, several investigations reported that SMG materials exhibited much lower activation energies for grain growth compared to large-grained materials, thus causing the enhanced grain growth. In this study, the apparent grain growth behavior of SMG Al-3 pct Mg fabricated by equal channel angular pressing was reappraised using Eq. In the analysis, the data of the variation of the grain size with annealing time and temperature were taken from Figure 12 in Reference 5 and Figure 7 in Reference 1, respectively.