Role of Zinc Volatilization on the Microstructure Development of Manganese Zinc Ferrites

Abstract

The role of Zn atmosphere on the microstructure development of Mn‐Zn ferrite prepared by alcholic dehydration was investigated. Discontinuous grain growth and intragranular porosity were observed throughout the specimen when a low oxygen partial pressure was employed during sintering. The microstructure of Mn‐Zn ferrite sintered in air resembled a mixture between Mn ferrite (uniform grain size) and Zn ferrite (exaggerated grain growth). Exaggerated grain growth was also observed on the surface of Mn ferrite sintered in the presence of a Zn‐rich atmosphere. The presence of Zn vapor phase enhanced the grain growth kinetics. The overall results indicate that a strict control of atmosphere is required in order to achieve a uniform pore‐free microstructure.