Remanence magnetization of iron oxide particles with different size distribution

Remanent magnetization curves for two samples of iron oxide particles with different size distributions were investigated. It was observed that the isothermal remanent magnetization curve and the DC demagnetization remanence curves are strongly depended on fine particle size. Moreover, it was figured out that remanent curves are quite complicated for the assembly of larger particles. In terms of remanence dependence analysis, it was shown that favourable interaction mechanism for the assembly of iron oxide particles strongly depends on particle size. The isothermal remanent magnetization curves were analysed in terms of the Stoner-Wohlfarth model. It leads to determine particle anisotropy field. It was found that the anisotropy field depends on particle size. It was assumed that observed differences related to different magnetic structure of particles. (paper)