Soft magnetic properties in Fe84−xB10C6Cux nanocrystalline alloys

► New Fe-based nanocrystalline Fe84−xB10C6Cux alloys are successfully synthesized. ► Cu addition suppresses the crystallization in this alloy system. ► The C-rich amorphous phase may inhabit grain growth. ► The Fe83B10C6Cu1 nanocrystalline alloy exhibits excellent soft magnetic properties. ► The alloy system has a large economical advantage and convenient productivity.