Tuning the morphology of soft magnetic phase to optimize the microstructure of SmCo5/α-Fe nanocomposites

Abstract Keeping a high proportion of soft magnetic phase with small grain size and uniform distribution of soft and hard magnetic phase is the key factor to fabricate bulk nanocomposites. We report a novel design to fabricate high performance SmCo5/α-Fe nanocomposites by choosing nanoscale α-Fe flakes as raw material of soft magnetic phase instead of micron scale α-Fe particles. Microstructure optimization, i.e., fine and dispersive distribution of α-Fe grains in SmCo5 matrix, and high soft magnetic phase proportion up to 25 wt% were achieved simultaneously. As a consequence, the remanence, intrinsic coercivity, and maximum energy product rise by 13.55%, 46.99%, and 80.03% in the SmCo5/α-Fe nanocomposites with 20 wt% α-Fe, respectively. Moreover, a giant remanence of 9.75 kG is achieved in the SmCo5/α-Fe nanocomposite with 25 wt% α-Fe nanoflakes content.