Simulation on the openness in recoil loop of nanocomposite magnet

Abstract

In this paper, the open recoil loop is simulated by establishing the simulation model of hard-phase grains (Sm2Co7) dispersed in soft-phase (α-Fe) matrix. The influence of inter-phase exchange coupling effect on the openness is simulated by adjusting the soft/hard phase interface integral exchange constant (Aint). The results show that the openness does not depend on the inter-phase exchange coupling effect, since the open recoil loops can be acquired even the Aint decrease from 20 to 0 pJ/m. The interaction energy density analysis also does not provide strong evidence to support the correlation between openness and exchange coupling effect. The magnetization configuration evolution shows the irreversible reversal of the hard-phase grains is root cause of the openness, and the adjacent soft phase enlarge the openness degree for the recoil loop of the nanocompiste magnet. Our results are helpful to deepen the understanding of the openness in recoil loops for nanostructural permanent magnet materials.