The influence of Cr substituted for Fe in Fe78-xCr xSi4Nb5B12Ag1 ribbons on the crystallization
and magnetic properties including the magnetocaloric effect have been investigated. DSC measurements
showed that the crystallization temperature and the crystallization activation energy increased with Cr
content. Thermomagnetic curves measured in low applied field indicated that there is a sharp ferromagneticparamagnetic
phase transition at Curie temperature, T C, of the amorphous phase. In addition, substitution of
Cr for Fe led to approximate linear decrease of TC with Cr content, namely from 450K to 280K for x 0 and
x 8, respectively. From a series of the isothermal magnetization curves M(H) measured at different
temperatures, magnetic entropy change ??Sm was determined at magnetic field variations of 13.5, 10.0 and
5.0 kOe. Maximum value of ??Sm (occurred near T C) decreased with increasing Cr content and these
values established are quite large at low field variation. Namely, at moderate low magnetic field variation of
5.0 kOe, |??Sm|max is of 4.4 and 1.9 J/kg.K for x 0 and x 8, respectively. Our studied alloys system could be
considered as the best magnetocaloric material candidates for magnetic refrigeration because of colossal
magnetic entropy change at low field variation and working temperature could be controlled in large region
by substitution effect. The anti-corrosion ability of alloys was also examined. ?? 2009 IOP Publishing Ltd.
