Monte Carlo simulations of strain-driven elemental depletion or enrichment in Cu95Al5 and Cu90Al10 alloys

摘要

An interatomic potential for the Cu-Al system based on the modified analytic embedded-atom method was proposed, which provides a reasonable description of the phase stability across the phase diagram. Combining with this potential, Monte Carlo simulations were performed to study strain-induced element segregation and intermixing in bulk and nanostructured Cu95Al5 and Cu90Al10 alloys. Al with a large atomic size is found to segregate to the tensile region while Cu to the compressive region. The elemental depletion or enrichment in dilute or nanostructured alloy is more notable than that in concentrated or bulk one, due to alloy effects or change of local stress. In particular, phase separation in nanostructured alloys leads to a single pure Cu inclusion in the matrix, which will induce strain hardening. The element segregation also affects the chemical ordering that will provide solid-solution strengthening. (C) 2015 Elsevier B.V. All rights reserved.