About this Abstract |
Meeting |
12th International Conference on Magnesium Alloys and their Applications (Mg2021)
|
Symposium
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12th International Conference on Magnesium Alloys and their Applications (Mg 2021)
|
Presentation Title |
Atomic-resolution Characterizations of Deformation Twins in Mg-Gd Alloys |
Author(s) |
Kai Guan, Daisuke Egusa, Gerardo Garces, Eiji Abe |
On-Site Speaker (Planned) |
Kai Guan |
Abstract Scope |
As one of the important deformation mechanisms, twinning plays a crucial role in plastic deformation and eventually in controlling the formability and mechanical properties of Mg alloys. In this work, extruded Mg-Gd alloys were compressed at 150 °C and 200 °C, and the corresponding compression curves exhibit obvious serrations. We investigated twin boundaries in the samples compressed to 4 % plastic strain by atomic-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The results indicate that numerous Gd atoms distinctly segregated at the interface between {10-12} twin and matrix, and the Gd-rich plane is always separated by steps. It is interesting to note that the average step height in samples with large serrations is greater than that in those with small serrations. Therefore, we deduce that the strong interaction between solute atoms and twin boundary leads to stress drops in serrated stress-strain curves. |
Proceedings Inclusion? |
Planned: At-meeting proceedings |