Asymmetric behavior of irreversible weak pinning at the soft/hard magnetically interface revealed by the open recoil loops

Analyzing the magnetization reversal process is crucial for enhancing the magnetic properties of nanocomposite magnets, thereby subsequently increasing the magnetic energy product and advancing the development of next-generation rare earth permanent magnet materials. Here, the open recoil loop is systematically investigated based on micromagnetic simulations and comparing magnetization configurations, which is strongly associated with the asymmetric behavior of weak pinning at the soft/hard magnetic interface. By removing and reapplying field, the irreversible weak pinning sites exhibit asymmetric behavior, leading to the formation of open phenomena in nanocomposites. The open degree of recoil loops obtained from experimental testing was also correlated with the irreversible magnetization, which supports the simulation results. Our findings provide a novel approach for understanding the magnetization reversal mechanism in nanocomposite magnets.