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arXiv · 1405.3688

Effect of Interfacial Structural Phase Transitions on the Coupled Motion of Grain Boundaries: A Molecular Dynamics Study

Timofey Frolov
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Abstract

In this work the coupled motion of two different phases of Σ5(210)[001] grain boundaries were investigated by molecular dynamics simulations of fcc Cu. The effect of interfacial structural phase transitions is shown to have a profound effect on both the shear strength and the nature of the coupled motion. Specifically, the motion of the two different phases is described by ideal coupling factors β<100> and β<110> that have different magnitudes and even signs. Additionally, the shear strength for the two inter- facial phases is observed to differ by up to 40 % at the lowest temperatures simulated. The study demonstrates that grain boundary phases transitions may have strong effects on the kinetics of microstructural evolution.

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Timofey Frolov. 2014-05-14. Effect of Interfacial Structural Phase Transitions on the Coupled Motion of Grain Boundaries: A Molecular Dynamics Study. https://doi.org/10.1063/1.4880715

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