Magnetic and structural properties of mechanically alloyed Tb0.257−x Nd x Fe0.743 alloys, with x = 0 and 0.257

Abstract

The alloys between a transition metal and a rare earth present magnetic and magneto optical properties of exceptional interest for the production of magnetic devices for information storage. In this work we report the magnetic and structural properties, obtained by Mossbauer spectrometry (MS) and X-ray diffraction (XRD), of Tb0.257−x Nd x Fe0.743 alloys with x = 0 and 0.257 prepared by mechanical alloying during 12, 24 and 48 h, to study the influence of the milling time in their magnetic and structural properties. The X-rays results show for all the samples that the α-Fe and an amorphous phase are always present. The first decreases and the second increases with the increase of the milling time. Mossbauer results show that the amorphous phase in samples with Nd is ferromagnetic and appears as a hyperfine field distribution and a broad doublet, and that as the milling time increases the paramagnetic contribution increases. For samples with Tb the amorphous phase is paramagnetic and appears as a broad doublet which increases with the milling time and for 48 h milling it appears an additional broad singlet.