Formation of strong 1-FePd/α-Fe nanocomposite magnets by visualizing efficient exchange coupling.

Conceptual nanocomposite magnets (NCMs) composed of exchange-coupled hard/soft magnetic phases have been expected to show excellent magnetic performance based on simultaneous high coercivity ( ) and high saturation magnetization ( ). In our previous works, however, the was considerably lower than its theoretical value ( ), which prevented us from improving the performance of NCMs. Here, we show that the of isolated particulate 1-FePd/α-Fe NCMs is dominated by their phase segregation into core/shell-like structures Janus-like structures.