Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1573048 | Materials Science and Engineering: A | 2016 | 7 Pages |
Abstract
The structures of a petaloid phase, which acts as the dominant intermetallic phase in a high-pressure die-cast Mg-4Al-4Sm-0.3Mn alloy with outstanding ductility and strength, were thoroughly studied in this work. The results indicate that the petaloid phase is Al2Sm phase (face-centered cubic structure: a=0.7945Â nm), not Al11Sm3, and composed of multiple (111) twins with the (111) plane serving as the twinning plane. However, most (111) twins are extraordinarily different from the conventional one, featuring a sandwiched structure with the filling being Al12Sm2Mn5 phase. Nevertheless, the appearance of Al12Sm2Mn5 bands is not always accompanied with twins. Finally, the underlying mechanisms for the peculiar Al2Sm structures were carefully discussed and revealed as a random heterogeneous nucleation of the Al2Sm phase on the pre-existed Al12Sm2Mn5 sites during solidification.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
Qiang Yang, Kai Guan, Xin Qiu, Deping Zhang, Shuhui Lv, Fanqiang Bu, Yaqin Zhang, Xiaojuan Liu, Jian Meng,