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arXiv · 0911.3724

Premelting of Al nonperfect (111) surface

F. L. Tang·X. G. Cheng·W. J. Lu·W. Y. Yu
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Abstract

Melting behaviors of aluminum (111) perfect/nonperfect surfaces, characterized by structure ordering parameter, have been investigated by classical molecular dynamics simulation with embedded atom method potential. Al (111) perfect surface has a superheating temperature above bulk Al melting point Tm, in this work, by about 80 K. Al nonperfect (111) surface has somewhat different local lattice structure from that on (111) perfect surface. Al nonperfect (111) surfaces tempt to premelt when temperature is less than Tm, in our simulation, by about 45 K. Aluminum atoms on the nonperfect surface zones are the sources of surface melting, and have larger velocities than those on the perfect surface zones.

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F. L. Tang, X. G. Cheng, W. J. Lu, W. Y. Yu. 2009-11-19. Premelting of Al nonperfect (111) surface. https://doi.org/10.1016/j.physb.2009.11.058

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