Phase Formation, Sintering Behavior, and Magnetic Properties of Low-Temperature Fired Mg-Cu-Zn Ferrites

The phase formation, sintering behavior, and magnetic properties of Mg–Cu–Zn ferrites with composition Mg1−x−yCuyZnx+zFe2−zO4−z/2 with 0.4 ≤ x ≤ 0.8; 0 ≤ y ≤ 0.35; and 0 ≤ z ≤ 0.06 were investigated. Ferrite formation from starting oxides is complete at 900°C. To guarantee sufficient densification at 900°C substoichiometric compositions with small iron deficiency z = 0.02 are required. Substitution of Cu for Mg with 0 ≤ y ≤ 0.35 in a ferrite with x = 0.5 has minor effect on permeability only; however, the shrinkage is significantly shifted to temperatures as low as T