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Abstract: In this research, the as-cast and as-homogenized Mg–8.2Gd–3.8Y–1.0Zn–0.4Zr alloy were subjected to the hot rolling with the same processing parameters. The microstructure and mechanical properties of the two kinds of as-rolled sheets were investigated. The sheet rolled from the as-cast alloy was mainly composed of recrystallized α-Mg grains surrounded by Mg3(Gd,Y) eutectic compounds. While the sheet rolled from the as-homogenized alloy was composed of large deformed grains with long-period stacking ordered (LPSO) phase inside and fewer recrystallized α-Mg grains, and exhibited higher strength due to the deformed grains with stronger basal texture and larger volume fraction of long-period stacking ordered (LPSO) phase. [Copyright &y& Elsevier]

Abstract: Mg–8.2Gd–3.8Y–1.0Zn–0.4Zr alloy sheets containing long period stacking ordered (LPSO) phase were prepared by hot rolling at 400°C with total reduction of 96%. Microstructure evolution of the sheets during hot rolling was investigated, and its influence on mechanical properties was discussed. Twinning occurred during the early stage of hot rolling, and disappeared after total reduction higher than 89%. Average grain size was gradually refined, microstructure became much more homogeneous and volume fraction of LPSO phase decreased with increasing rolling reduction. Furthermore, the type of LPSO phases far from and near the block shaped phases were identified to be different. Basal texture was obtained during rolling process, but the intensity declined with the further rolling, which is mainly due to the dynamic recrystallization and the addition of RE elements. The as-rolled sheet with 96% reduction shows excellent mechanical properties: yield strength of 318MPa, ultimate tensile strength of 403MPa and elongation to failure of 13.7% at ambient temperature along the rolling direction. [Copyright &y& Elsevier]