Some materials considerations in particulate media

Three areas of current interest in particulate recording media are examined. The first concerns the reversal modes in recording particles-in particular whether the classical coherent and incoherent modes are more appropriate than that of heterogeneous nucleation and growth of regions of reversed magnetization. Secondly, magnetization relaxation is considered, with emphasis on its role in defining the observed coercivity. Finally, the effects of coating particles are discussed, especially the epitaxial Co-coated materials.