Stress induced MnZn ferrite synthesis from pickling plant by-product of steel industry

Abstract

MnZn ferrites synthesized from the pickling by-product powder (Fe₂O₃) of the steel industry by varying Zn and Mn stoichiometry. A single step solid-state synthesis process in argon atmosphere with rapid atmospheric cooling was followed to achieve structurally modified MnZn ferrite with low coercivity. Among the stoichiometric variations, Mn-rich variant exhibited a highly strained body centered tetragonal (BCT) mixed spinel structure Mn_0.75Zn_0.75Fe_1.5O₄ with Fe(Mn) octahedra distortion stabilized through the synthesis parameters. It demonstrates extremely low coercivity of 10.34 A/m i.e., 0.13 Oe, shallow hysteresis loss of 0.456 J/m³, along with high permeability and high saturation magnetization. Phase evolution studies of all the synthesized powders were done through DTA-TG and Raman spectroscopy. The crystal structures were determined and verified through XRD and TEM respectively, while the morphologies were studied using SEM. Effect of Mn incorporation was studied through first-order electronic structure calculations capturing Bohr magneton, energy per unit cell and corresponding saturation magnetization which was experimentally verified through VSM. This work outlines a critically designed single step solid state synthesis process which can stabilize a highly strained BCT structured MnZn ferrite with a particular stoichiometry making it suitable for advanced soft magnetic core application.