Mixed Ba-hexaferrite: An experimental investigation of thermal, structural, morphological, and magnetic properties of hexa-phasic magnetocomposite and its constituting phases

Abstract

Magnetocomposite materials have expanded their attention in recent years due to the focused and continuously growing applicability of these nanostructured materials. The successful outcomes of blending several magnetic phases may offer the development of a surprisingly new magnetic phenomenon or superior magnetic performance than conventional magnetic materials. This research work involves the synthesis of six types of barium hexaferrite (BaHF) phases, i.e., Y, M, W, X, U, Z-type, along with mixed Ba-hexaferrite (blending all six phases) and its thorough investigation of magnetic characteristics with a wide range of temperatures (2 K–900 K). The insightful and comparative understanding of the thermal reactions during phase formation within all six phases is explained by determining kinetic parameters. The magnetic parameters concerning each barium hexaferrite phase are explained by the structural and morphological constraints. The sintered mixed Ba-hexaferrite consists of a room temperature ferrimagnetic behavior (Ms = 74.85 emu/g, Hc = 45.35 Oe) and exhibits a deviation from its theoretical values (using Vegard's law), revealing the presence of interphasic interaction within it. The low-temperature spin dynamics confirm the existence of a spin-glass state at 110 K, including a broader magnetic susceptibility response starting at 185 K, associated with the evolution of a reentrant spin-glass state.