Magnetic properties of amorphous iron-rare-earth-boron alloys

Abstract
The magnetic properties of Fe77R15B8 melt-spun ribbons with R=Y, La, Pr, Nd, Sm, Gd, Tb, Dy and Er are reported in the temperature range 4.2-800K. The ordering temperatures of these alloys are found to be in the range 90-300 degrees C and are well below the crystallisation temperatures. Fairly large magnetic hysteresis (1.5-8 kOe) is observed for alloys containing Er, Sm, Dy and Tb at 4.2K. Strong temperature dependence of coercivity is observed which in certain cases follows an exponential law.