The phase diagrams with influence of biquadratic exchange coupling on martensitic-austenitic transformations for core-surface nanoparticles

YALCIN O., ERDEM R., Özüm S., Demir Z.

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, cilt.389, ss.120-123, 2015 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 389
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1016/j.jmmm.2015.04.056
  • Dergi Adı: JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.120-123
  • Anahtar Kelimeler: Phase diagrams, Core-surface nanoparticles, Martensitic/austenitic transitions, ISING NANOWIRE, MAGNETIC-PROPERTIES, MODEL
  • Akdeniz Üniversitesi Adresli: Evet

Özet

Recently, origin of the martensite-austenite transitions in core-surface type magnetic nanoparticles has been investigated theoretically and it has been indicated that repulsive biquadratic exchange coupling (K < 0.0) causes the coexisting martensite and austenite phases. In the present paper, the phase diagrams of homogeneous and composite nanoparticles in the k(B)T/J(0)-D/J(0) plane are studied for the presence and absence of attractive biquadratic exchange interaction in addition to repulsive biquadratic exchange interaction. Significant changes in the phase diagram points are discussed in the presence of martensitic and austenitic transformations. Four regions in the phase diagrams are found as second-order, martensitic-austenitic, T-cid and first-order phase transition regimes. (C) 2015 Elsevier B.V. All rights reserved.