TEMPERATURE DEPENDENT COERCIVITY AND RELAXATION PHENOMENA IN AMORPHOUSFe–(Mn)–Zr–BNANOPARTICLES

Abstract

We report the temperature dependent coercivity behavior and the improvement of room temperature soft magnetic properties in interacting amorphous Fe–Mn–Zr–B powder nanoparticles prepared by mechanical alloying of elemental powders. With increasing Mn concentration from 5 to 20 at.% in Fe–Zr–B alloys, the coercivity (HC) reduces drastically from 170 to 25 Oe. Temperature dependent HCbehavior shows exponential variation of HCwith temperature. Interparticle interactions dominate the low temperature behavior and surface effect on the nanoparticles is more pronounced at low temperatures. Magnetic relaxation behavior shows slow relaxation in the interacting amorphous nanoparticles and the relaxation process is observed to be thermally activated in the present studies.