Recent Advances and Remaining Challenges in Manufacturing of Amorphous and Nanocrystalline Alloys

A review of advanced Fe-based amorphous and nanocrystalline soft magnetic alloys that are currently being used in the market and their primary industrial applications is discussed as well as emerging trends. The high-efficiency distribution transformer market continues to be the largest segment by volume for Fe-based amorphous foil. The industry has been shifting toward higher induction levels (1.63 T) with increased stacking factor (>90%) to minimize the transformer size and reduce costs. New magnetic domain refined grades of amorphous foil are now commercially available which show a reduction of ~25% in core losses compared to the standard amorphous material. Nanocrystalline soft magnetic alloys have become the standard material for many applications including low-loss electrical components, magnetic shielding, electronic filtering, medium frequency transformer cores, and a variety of others. The nanocrystalline alloys are commonly cast fully amorphous and devitrified through controlled heat treatments. New nanocrystalline alloy compositions and processing methods have enhanced both the mechanical and magnetic performance of the final properties. Amorphous and nanocrystalline alloys show promise for use in electric motors but fabrication challenges for limited their commercial adoption.