2007 Volume 54 Issue 1 Pages 10-14
La(Fe1-xSix)13 alloys with the NaZn13-type structure were prepared from rapidly solidified ribbons via a short annealing treatment. The rapid solidification process was realized by using a laboratory scale melt-spinning apparatus and a large strip-casting facility. The rapidly solidified ribbons contained a large amount of the NaZn13-type phase together with an α-(Fe-Si) phase and a La-rich phase. The finely dispersed α-(Fe-Si) and La-rich phases readily combine to form the NaZn13-type phase upon a short-time annealing. The magnetic part of the entropy change near the Curie temperature at about 190 K was estimated from magnetization vs. temperature measurements to be about −20 J/K/kg for a field change between zero and one T. The process developed in this work may be applied to a mass production of thin slabs of La(Fe1-xSix)13 alloys of thickness around 100μm as the starting material for production of coarse powder of hydrogenated La(Fe1-xSix)13 alloy.
