DELTA-H PLOT EVALUATION OF REMANENCE BEHAVIOR IN BARIUM FERRITE TAPES AND DISKS

Remanence studies in recent years have used the characteristics of the Henkel plot and the delta-M plot in the interpretation of interaction field effects in particulate magnetic media. Studies of these two plots in ordered BaFe coatings, however, indicate that both plots give inadequate description of interaction field effects. An alternative to the delta-M plot is the delta-H plot in which, essentially, the (normalized) susceptibility curves for the isothermal remagnetization and dc demagnetization processes are differenced horizontally (rather than vertically as in the delta-M plot). It is shown here that the delta-H plot is a more direct way of examining the interaction fields. Simulated delta-H plots are presented based on a recent mean field model by Che and Bertram and are compared with measurements made on oriented BaFe coatings.