A hybrid model to calculate the magnetization of nanostructured permanent magnetic materials

Abstract

We present our simulated initial magnetization curves for nanostructured permanent magnets based on a simple hybrid model. The model assumes that the reversible change in the magnetization curves obeys the Stoner-Wohlfarth (SW) model while the irreversible part can be attributed to the motion of the transition region (TR), which is a domain-wall-like magnetic moment distribution formed in the grain boundary due to exchange interaction between neighboring grains with different easy axis orientations. The calculated full hysteresis coercivity Hcm (=0.14HK) is in reasonable agreement with available experimental data, where HK is the anisotropy field. Both the calculated remanence Mr and coercivity Hc increase rapidly with the maximum applied field Hm at lower field (H m