Study on structural and magnetic properties of Ni _0.8Zn _0.2Fe ₂O ₄

Recently, sintering experiments have received much attention for the study of magnetic properties of microwave absorbers, a cation that can change inverse spinel into normal spinel [1]. Although, in the field of materials science conditions excluding temperature for processing ferrite, for microwave absorbers have been reported, there are few reports on the investigation of its magnetic properties at various annealing temperatures. This paper describes ferrite synthesis based on the sintering method and magnetic properties of ferrite at various annealing temperatures. Reduction seemed to have an influence on magnetic properties because of the existence of Ni, preventing synthesis of ferrite as the annealing temperature increased. Such increase seemed to show that Ni is ferrimagnetic. From the Mossbauer spectrum, there were two sextets of magnetic fields to A-site and B-site, applying to the nucleus [2]. For the A-site, the relative absorption area decreased and the internal magnetic field increased. However, for the B-site the relative absorption area increased and the internal magnetic field decreased as annealing temperature rose from 800°C to 1100°C, because in the state forming Zn-ferrite first, Ni-ferrite formed easily at a high annealing temperature.