Atomic and Magnetic Ordering in bcc Cu-Al-Mn: Computational Study

The β phase of the ternary alloy Cu-Al-Mn, with bcc structure, displays an interesting variety of long-range atomic ordering and magnetic transitions. In this work, we present a model that allows an accurate reproduction of the measured critical temperatures for alloys with compositions along the ps...

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Detalles Bibliográficos
Autores: Alés, Alejandro, Lanzini, Fernando Gabriel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2014
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/100882
Acceso en línea:http://hdl.handle.net/11336/100882
Access Level:acceso abierto
Palabra clave:ATOMIC ORDERING
CU-AL-MN
MAGNETISM
MONTE CARLO SIMULATIONS
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:The β phase of the ternary alloy Cu-Al-Mn, with bcc structure, displays an interesting variety of long-range atomic ordering and magnetic transitions. In this work, we present a model that allows an accurate reproduction of the measured critical temperatures for alloys with compositions along the pseudobinary line Cu3Al-Cu2AlMn. The method is based on the Monte Carlo technique, allowing simultaneous evolution of the atomic distribution and the magnetic state. The configurational part of the energy is represented with a three-state Hamiltonian; the six interchange energies that govern the chemical interactions between nearest and next-nearest neighbours atoms have been determined. The magnetic counterpart is modelled by means of an Ising model. The predicted Curie temperatures agree well with the experimental values when it is assumed that the crystal configuration remains fixed and with the maximum possible degree of atomic ordering. The effects of configurational disorder on the magnetic transition have been evaluated.