Orientations of nuclei during static recrystallization in a cold-rolled Mg-Zn-Gd alloy

The static recrystallization process of a cold-rolled Mg-Zn-Gd alloy was tracked by a quasi-in-situ electron backscatter diffraction method to investigate the orientations of nuclei. The results show that orientation distribution of nuclei is associated with nucleation mechanism. The continuous static recrystallization nuclei display similar orientations to the parent grains with TD orientation. Differently, discontinuous static recrystallization nuclei formed within the parent grains (TD-45 degrees orientation) show random orientations and a variety of misorientation angles but preferred axes <<(5)over bar>273> or <<(5)over bar>270>. Interestingly, a special oriented nucleation is found. Discontinuous static recrystallization nuclei originated from boundaries of the parent grain (TD-70 degrees orientation) show concentrated TD orientations in another side due to the preferred misorientation relationship 70 degrees <11<(2)over bar>0> (Sigma 18b). It is speculated that these two special misorientation relationships are related to the dislocation type. (C) 2020 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.