Effect of Co-substitution on the structure and magnetic properties of MnZn power ferrite

MnZn power ferrites with a composition of Mn_0.681-xZn_0.246Fe_2.073Co_xO₄ were prepared by conventional ceramic technique. The samples were sintered in a computer-driven furnace at 1320 °C for 4 h. Then the influences of Co-substitution on the crystalline structure, microstructure and the magnetic properties of MnZn power ferrite were studied. It shows that Co-substitution has not changed the structure of MnZn ferrite, but improved the crystallization. With the increase of Co substitution content, Co²⁺ ions firstly replace Mn²⁺ ions and then replace Fe³⁺ ions. And at room temperature, the initial permeability increases with the increase of Co-substitution content. Co-substitution can also reduce the porosity and the power loss. In addition, the corresponding temperature of the minimum power loss shifts to a lower temperature.