The origin and enhancement of {0001}〈112¯0〉 texture during heat treatment of rolled AZ31B magnesium alloys

Electron backscatter diffraction data from warm-rolled AZ31B, a commercial Mg alloy, are used as microstructural input into a Monte Carlo Potts grain growth model. It is shown that the {0 0 0 1}〈111¯0〉 texture, recently discovered to strongly evolve during grain growth annealing, is the result of a grain size advantage that emerges during recrystallization; where grains closer to the {0 0 0 1}〈112¯0〉 orientation are larger on average than competing {0 0 0 1}〈101¯0〉 oriented grains. As a consequence, there is no need to invoke anisotropy in grain boundary energy or mobility to quantitatively model the relationship between grain growth and texture. The observed textural evolution shows a surprising similarity to that of hexagonally close packed Zr alloys despite underlying differences in the deformation mechanisms between the two alloy systems. Crystal plasticity simulations, however, reveal that the faint underlying {0 0 0 1}〈101¯0〉 deformation texture in this Mg alloy is due to prismatic slip activity during rolling.