Influence of Ge and Bi substitution on the magnetic and magnetocaloric properties of LaFe11.4Si1.6
Küçük Resim Yok
Tarih
2010
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Natl Inst Optoelectronics
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
In this work, the magnetic and magnetocaloric properties of LaFe11.4S1.6-xGex (x = 0.05, 0.1 and 0.2) and La1-xBixFe11.4Si1.6 (x = 0, 0.1 and 0.2) compounds have been investigated. X-ray results indicate that the samples with lower Ge and Bi contents mainly consist of the NaZn13-type phase with a small amount of alpha-Fe impurity phase. The alpha-Fe impurity phase increases with increasing concentrations of Ge and Bi. The Curie temperature of the samples also increases slightly with increasing Ge and Bi contents. The spin-wave dispersion coefficient D, exchange constant J and average mean-square range of exchange interaction ()(1/2) have been calculated. The increase in Curie temperature is attributed to an increase in the average Fe-Fe distance and ferromagnetic interactions. The peak values of the magnetic entropy change vertical bar Delta S-m vertical bar are found to decrease with increasing Ge and Si contents. This is attributed to a change of the phase transition from first order to second order. The peak values of vertical bar Delta S-m vertical bar are 22.38 J/kg K for LaFe11.4Si1.6, 12.58 J/kg K for LaFe11.4Si1.5Ge0.1 and 14.25 J/kg K for La0.9Bi0.1Fe11.4Si1.6 at a magnetic field of 6 T.
Açıklama
Anahtar Kelimeler
NaZn13-type intermetallics compounds, Magnetocaloric effect, Magnetic entropy change, LaFeSi
Kaynak
Journal of Optoelectronics and Advanced Materials
WoS Q Değeri
Q4
Scopus Q Değeri
Q4
Cilt
12
Sayı
5
