Segregation and phase separation in nanocrystalline materials

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Surface segregation has been calculated in a slab of thickness d. In ordering AB systems there is a competition between the surface segregation of A atoms and bulk ordering, and either a surface disturbed region or an antiphase boundary can be formed inside the slab. With decreasing d the average order can decrease well below the bulk value. In phase separating systems with strong segregation a phase separation from the surfaces develops and two layers of the A-rich phase cover the A-poor phase in the slab (lamellar structure) and there is an enrichment of A atoms in the near surface layers of the upper phase. For weakly segregating systems if T is below a certain temperature, Tb, A-rich and A-poor phases can be in equilibrium in a columnar structure. With decreasing d there is an increased as well as a decreased solubility in A-poor and in A-rich phases, respectively. It was shown that a segregation stabilisation of the nanostructure is possible and with increasing d there is a sharp surface phase transition from a large to a small coverage.

Original languageEnglish
Pages (from-to)665-668
Number of pages4
JournalNanostructured Materials
Volume9
Issue number1-8
Publication statusPublished - 1997

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Nanocrystalline materials
Phase separation
nanocrystals
Surface segregation
slabs
Atoms
Lamellar structures
antiphase boundaries
Nanostructures
Stabilization
Solubility
Phase transitions
atoms
surface layers
solubility
stabilization
Temperature

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Segregation and phase separation in nanocrystalline materials. / Beke, D.; Cserháti, C.; Szabó, I.

In: Nanostructured Materials, Vol. 9, No. 1-8, 1997, p. 665-668.

Research output: Contribution to journalArticle

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