Large-size anisotropic bulk SmCo/Fe(Co) nanocomposite magnets prepared by hot rolling at extreme conditions

A macroscopically large-size anisotropic bulk SmCo/Fe(Co) nanocomposite magnet with a small grain size (∼10 nm) and a (00l) texture along easy magnetization axis has been prepared by rolling the heated Sm-Co amorphous precursors containing α-Fe(Co) nanocrystals at large strain and high stress. This anisotropic magnet exhibits a significantly enhanced energy product of 21 MGOe compared with that (14.5 MGOe) of the corresponding isotropic magnet. This enhanced property is attributed to the remanence enhancement which results from the SmCo7 hard-phase grain alignment along easy magnetization axis and the small grain size for the soft and hard phases. The large size and high-performance of the fabricated magnets and the simplicity of manufacturing make them great potential for practical applications.