Magnetic, magnetocaloric and neutron diffraction studies on TbNi5-xMx (M = Co and Fe) compounds

TL;DR

This study explores how substituting Co and Fe in TbNi5 affects its structural, magnetic, and magnetocaloric properties, revealing significant changes in Curie temperature and magnetic moment distribution, with implications for magnetic cooling applications.

Contribution

It provides new insights into how transition metal substitution alters magnetic and magnetocaloric behaviors in TbNi5-based compounds.

Findings

Fe substitution significantly increases Curie temperature.

Neutron diffraction shows redistribution of magnetic moments.

Magnetocaloric properties are strongly correlated with magnetic behavior.

Abstract

The effect of substitution of Co and Fe for Ni in TbNi5 on the structural, magnetic and magneto-thermal properties has been investigated. Considerable enhancement of Curie temperature is observed with Fe substitution, whereas the increase is nominal in the case of Co. Neutron diffraction measurements reveal the redistribution of moments and site preference of substitutional ions in Ni 2c and 3g sites. In TbNi4Fe, both Ni and Fe as well as Tb are found to carry moment while in the case of TbNi4Co, mainly Tb carries the moment. Magnetocaloric behavior has been investigated from the magnetization and the heat capacity measurements. The magnetic and magnetocaloric properties are found to be strongly correlated in these compounds.