Dynamic recrystallization mechanism of Mg-8.5Gd-2.5Y-0.4Zr alloy during hot ring rolling

Dynamic recrystallization (DRX) behavior of Mg-8.5Gd-2.5Y-0.4Zr alloy subjected to hot ring rolling was investigated in this paper. Three different DRX mechanisms were identified based on TEM: fragmentation of lamellar structures, transformation of subgrains separated by dislocation arrays, and strain-induced boundary bulging mechanism. Therein, the first one is a novel mechanism that has not been reported before in magnesium and its alloys. Preliminary analysis suggests that this mechanism might result from the high strain rate and continuous repeated rolling deformation provided by hot ring rolling.