MAGNETIC INTERACTION BETWEEN MAGNETITE PARTICLES DISPERSED IN CALCIUMSILICATE GLASSES

The effect of the measuring process on the magnitude of the inter-part icle interaction has been investigated by measuring the superparamagne tic relaxation for magnetite particles dispersed in calciumsilicate gl asses using thermoremanent magnetization (TRM), AC susceptibility and Mossbauer spectroscopy measurements: The temperature dependence of the remanent magnetization in TRM measurements can be explained by Neel's theory which describes the superparamagnetic relaxation of a noninter acting particle. On the other hand, the relation between log(10) tau(m ) (tau(m): the measurement time) and 1/T-B (T-B: the average blocking temperature) in AC susceptibility measurements can be interpreted usin g Dormann's model in which the inter-particle interaction is tak;en in to account. Therefore, it can be concluded that the measuring process for the superparamagnetic relaxation can be more or less sensitive to the inter-particle interaction.