Role of yttrium in the microstructure and texture evolution of Mg

Texture weakening and static recrystallization in rolled Mg–2.9Y and Mg–2.9Zn solid solution alloys

“…The molten alloys were cast into plates measuring 120 mm 9 100 mm 9 6 mm in a steel mold pre-heated at 400°C. To obtain single-phase a-Mg solid solution before rolling, the as-cast Mg-2.9Y and Mg-2.9Zn alloys were heat treated at 430°C for 24 h and 8 h, respectively [9].…”

“…The orientation distribution function (ODF) was constructed from the incomplete pole figures of {10.0}, {00.2}, and {10.1} using the arbitrary defined cell (ADC) method by TexTools software. Recalculated pole figures as well as the distribution of basal planes [9] were then derived from the ODFs. Microtexture was studied via electron backscattered diffraction (EBSD) technique in a Hitachi S-3000 FE-SEM fitted with a TSL EBSD camera operating at 20 kV, 70°-tilt angle and a step size ranging between 0.3 and 0.5 lm.…”

“…Considerable effort is currently being devoted to weaken the basal texture as an efficient route for improving formability. One approach for texture weakening is the addition of rare-earth (RE) element to Mg. Based on previous studies, the addition of RE elements leads to significantly weaker textures [5,6], e.g., after multi-pass rolling [2,7], or after post-deformation annealing [8][9][10][11].…”

“…This is not generally the case for Mg alloys in which other nucleation mechanisms are operative [15][16][17]. Moreover, texture weakening has also been observed in the absence of precipitates in Mg-RE solid solution alloys [6,7,9]. Stanford and Barnett [18] found a non-conventional texture component in recrystallized grains at shear bands after the hot extrusion of an Mg-Gd solid solution alloy.…”

“…It has been shown in previous studies [8,9] that the presence of Y in a-Mg solid solution phase inhibits dynamic recrystallization (DRX) during hot deformation. Consequently, a high level of energy is stored within microstructure, especially in deformed grains with basal orientation.…”