Anhysterese und remanenzkurven in metallischen werkstoffen zur magnetischen aufzeichnung

The remanent magnetization of some workable hard magnetic materials has been measured by different methods as a function of the applied field. The results are well suited for providing information on the interaction between the fine particles within an assembly. First, the anhysteretic susceptibility is discussed in connection with the so-called triplet-curves of remanent magnetization with regard to the conceptions derived from the pair-model. Second, quantitative indications on interaction fields are given from the deviation from the Gaussian distribution with logarithmic divided abscissa occurring in practical assemblies. As a rule, they accordingly consist of a negative, magnetization-independent and a positive, magnetization-dependent term. In any case, small differences from the triplet-curves of remanent magnetization must not be a symptom of little interaction; it may be feigned by the superposition of the two terms. Finally, partial remanent magnetization is discussed. If interactions occur, the "additive law" is no more valid, i.e., the sum of the remanent magnetizations acquired over successive intervals is not the same as that acquired over the total interval in one step. It is shown that, under certain conditions, the effect of the magnetization-dependent term may be suppressed.