Magnetic properties of amorphous RE65Al35alloys

Ribbons of amorphous RE
65
Al
35
alloys (where RE = Ce, Pr and Dy) were prepared by melt spinning under vacuum. Magnetization measurements, carried out on a vibrating sample magnetometer with magnetic fields
H \leq 20
kOe and over a temperature range 2.8°K
\leq T \leq 300
°K, are reported here. Dy
65
Al
35
and Pr
65
Al
35
demonstrated a ferromagnetic-like ordering which was characterized by the appearence of a cusp at 30 °K and 7 °K, respectively. In both cases, hysteresis and relaxation effects occurred below the ordering temperature. Amorphous Ce
65
Al
35
exhibited a negative paramagnetic Curie temperature of -40 °K, but did not order for temperatures down to 2.8 °K. The results are discussed in terms of the random atomic arrangement and its influence on the exchange and anisotropy interactions.