材料期刊网

The thermal stability, magnetocaloric effect, and refrigeration capacity (RC) of Gd-based Gd(65)Fe(20)Al(15-x)B(x) (x=0-7) glassy ribbons have been investigated. A relatively wide supercooled liquid region Delta T(x)(Delta T(x)=T(x)-T(g)) (50-80 K) and large reduced glass transition temperature T(rg)(T(rg)=T(g)/T(m)) (>0.63) are found in Gd(65)Fe(20)Al(15-x)B(x) glassy ribbons. The distinctive glass transition and sharp crystalline events as well as large values of Delta T(x) and T(rg) confirm the excellent glass forming ability of these alloys. The maximal magnetic entropy changes, -Delta S(M)(max), and RC values of the specimens are about 4.80-5.21 J/kg K and 700-800 J/kg under 50 kOe, respectively. These -Delta S(M)(max) values are comparable to or even higher than that of some reported bulk metallic glasses. Moreover, the larger RC values are due to the broad Delta S(M) peak (similar to 200 K), which is caused by the glassy structure. The large Delta S(M) and RC values make the Gd-based Gd(65)Fe(20)Al(15-x)B(x) glassy ribbons attractive candidates for magnetic refrigeration materials. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3335498]