Influence of Milled Powder Particle Size Distribution on the Microstructure and Electrical Properties of Sintered Mn‐Zn Ferrites

The grain growth and densification rates of Mn-Zn ferrites during sintering are closely linked to the characteristics of the calcined and milled powders used. Long milling times enlarge powder particle size distributions and tend to promote discontinuous grain growth during sintering. For fixed sintering conditions, an optimum milling time, which corresponds to minimal eddy current and hysteresis losses, exists. The electrical properties of overmilled powders deteriorate greatly because duplex structure occurs. Theoretical analysis of the probability of discontinuous grain growth occurring during sintering in relation to powder particle size distribution agrees with the experimental results.