Effect of heating rate on densification and magnetic properties of MnZn ferrites sintered by multiphysical fields coupling methodology

Abstract

This work has provided a novel idea of fabricating MnZn bulk ferrite materials. MnZn ferrite powders with a composition of Zn_0·8Mn_0·2Fe₂O₄ (wt-%) were sintered under coupled multiphysical fields applied by Gleeble-1500D thermal simulation instrument. Cylindrical bulk ferrites with a diameter of 2·5 mm and a height of 2·5 mm were prepared, and the effect of heating rate on densification and magnetic properties of MnZn ferrites was studied. The results show that the densification and magnetic properties of MnZn ferrite were directly affected by the heating rates. A relative density of up to 98·5% was achieved when the heating rate of 100°C s⁻¹ was used. Such magnetic properties as maximum energy product and remanence of MnZn ferrite sintered under coupled multiphysical fields are improved when compared to samples produced by conventional sintering. In particular, a 204·39% increase in maximum energy product is obtained. Finally, the densification mechanisms of multiphysical fields sintering method are discussed.