Self- and impurity cation diffusion in manganese–zinc-ferrite, Mn1−x−yZnxFe2+yO4 Original Research Article

Self-diffusion coefficients of Mn, Fe and Zn and the impurity diffusion coefficient of Co in polycrystalline Mn–Zn-ferrite, Mn0.54Zn0.35Fe2.11O4, have been measured by applying the radioactive isotopes 54Mn, 59Fe, 65Zn and 57Co simultaneously. The experiments were conducted at a temperature of 1200°C, as a function of oxygen activity. For comparison purpose, we performed similar diffusion experiments also on Mn-ferrite, MnFe2O4, at the same experimental conditions. We analyzed our tracer diffusion experiments using both the residual activity and the tracer sectioning method. The diffusion coefficients of all the isotopes show a minimum as a function of the oxygen activity indicating that two types of defects, cation vacancies and cation interstitials, contribute to the cation tracer diffusion in both systems. In this paper, we present the experimental results and a defect chemical analysis of Mn–Zn-ferrite to discuss the influence of the Zn-content on the cation diffusion in Mn–Zn-ferrite.