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arXiv · 1611.05290

The original nucleation and migration of the basal/prismatic interfaces in Mg single crystals

Qun Zu·Xiaozhi Tang·Shuang Xu·Yafang Guo
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Abstract

The formation of basal/prismatic (BP) interfaces accompanying with the nucleation and growth of a reoriented crystal in Mg single-crystals under c-axis tension is investigated by molecular dynamics simulations. The BP interfaces nucleate by shuffling mechanism via local rearrangements of atoms. Both two-layer disconnections and one-layer disconnections contribute to the migration of BP interfaces. In a three-dimensional view, the BP interfaces relatively tend to migrate towards the [1-210] direction rather than the [-1010]/[0001] direction since the misfit disconnection or misfit dislocation caused by the accumulation of mismatch along the [-1010] /[0001] direction impedes the disconnection movement. The BP interfaces can transform to the {10-12} twin boundary (TB) and vice versa. While the process from BP interface to TB is described as the linear pile-up of interface disconnections, the versa transformation is proposed as the upright pile-up process. Both BP transformation and {10-12} twinning can efficiently accommodate the strain along the c-axis, and the conjugate BP interfaces and {10-12} TBs account for the large deviations of twin interfaces from the {10-12} twin plane.

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Qun Zu, Xiaozhi Tang, Shuang Xu, Yafang Guo. 2016-11-16. The original nucleation and migration of the basal/prismatic interfaces in Mg single crystals. https://doi.org/10.1016/j.actamat.2017.03.035

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