DELTA-H PLOT EVALUATION OF REMANENCE BEHAVIOR IN BARIUM FERRITE TAPESAND 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 plo ts in ordered BaFe coatings, however, indicate that both plots give in adequate description of interaction field effects. An alternative to t he delta-M plot is the delta-H plot in which, essentially, the (normal ized) susceptibility curves for the isothermal remagnetization and dc demagnetization processes are differenced horizontally (rather than ve rtically as in the delta-M plot). It is shown here that the delta-H pl ot 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.