Magnetocaloric effect in Tb5Si2-xGe2-xFe2x (0 <= 2x <= 0.1) compounds

The influences of iron-alloying on the structure, magnetic and magnetocaloric properties of the Tb5Si2Ge2 compound have been studied using X-ray powder diffraction and magnetization measurements. X-ray diffraction studies show that both the alloyed and non-alloyed samples crystallize in the P112(1)/a monoclinic structure at room temperature. As the temperature is lowered, a first-order magnetic transition is observed in the parent compound, whereas only a second-order magnetic transition is recorded for the compounds alloyed with iron. Iron-alloying in small amounts of 2x approximate to 0.05 reduces the magnetic hysteresis significantly while retaining the magnitude of the change in magnetic entropy change. (C) 2008 Elsevier B.V. All rights reserved.