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Monte Carlo Study of Ordering and Domain Growth in a Class of fcc-Alloy Models

Michael Kessler·Wolfgang Dieterich·Andrzej Majhofer
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Abstract

Ordering processes in fcc-alloys with composition A_3B (like Cu_3Au, Cu_3Pd, CoPt_3 etc.) are investigated by Monte Carlo simulation within a class of lattice models based on nearest-neighbor (NN) and second-neighbor (NNN) interactions. Using an atom-vacancy exchange algorithm, we study the growth of ordered domains following a temperature quench below the ordering spinodal. For zero NNN-interactions we observe an anomalously slow growth of the domain size L(t) \sim t^α, where α\sim 1/4 within our accessible timescales. With increasing NNN-interactions domain growth becomes faster and αgradually approaches the value 1/2 as predicted by the conventional Lifshitz-Allen-Cahn theory.

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Michael Kessler, Wolfgang Dieterich, Andrzej Majhofer. 2003-03-04. Monte Carlo Study of Ordering and Domain Growth in a Class of fcc-Alloy Models. https://doi.org/10.1016/j.physa.2003.08.021

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