Lattice strain caused magnetism and magnetocrystalline anisotropy in Zn modified barium hexaferrite

Abstract

The Rietveld refinement of XRD patterns reveals the crystallization of all the materials (BaFe12-xZnxO19 for x = 0.0, 0.2, 0.4, and 0.6) to hexagonal symmetry with space group P63/mmc. The lattice strain created in the crystal due to the ionic size mismatch of Zn and Fe. The Law of Approach (LA) to saturation method is employed to obtain the saturation magnetization (Ms) and magnetocrystalline anisotropy constant (K1) from M−H hysteresis loop. The maximum saturation Magnetization (Ms) and minimum coercivity are found to be for BaFe11·8Zn0·2O19 (i.e., x = 0.2). The magnetocrystalline anisotropy constant (K1) reduces with the increase in temperature. The magnetic properties and magnetic crystalline anisotropy in Zn modified barium hexaferrite have been explained by considering the strain in the lattice site and superexchange interaction.