MAGNESIUM-ZINC FERRITE WITH COPPER SUBSTITUTIONS

The effects of Mg substitution by Cu on the properties of MgZn ferrite s sintered at low temperature were investigated. The densification of MgCuZn ferrites is dependent upon Cu content in the composition Mg0.5- xCuxZn0.5Fe2O4 + 0.5 MgO. From the sintering experiments carried out b etween 800 and 1100 degrees C it was established the optimum amount of CuO (x - 0.3) which is sufficient to promote sintering at low tempera ture (1050 degrees C) and to yield a dense material (4.5 g/cm(3)). It was evidenced a break in the resistivity for x > 0.3 when it decreases by four orders of magnitude. The strong dependence of the material pa rameters on the Cu ions content is consistent with the microstructural changes induced by copper ions which favour the lattice diffusion pro cess.