Preparation of cast-iron-based nanocrystalline alloy with Cu and Nb addition

The effect of minor Cu and Nb addition on glass-forming ability and nanocrystallization behavior of cast-iron-based bulk metallic glass was investigated. With simultaneous Cu and Nb addition, the crystallization kinetics of the amorphous alloys adequately modified to have enlarged initial nucleation rate and reduced growth rate of the primary α-Fe phase. However, due to the increased tendency to form secondary Fe₃C and Fe₂P phase, the cast-iron-based bulk metallic glass with combined Cu and Nb addition had a reduced processing window for nanocrystallization. Also, the simultaneous Cu and Nb addition decreased glass-forming ability of the alloy. Thus, it was revealed that the classical nanocrystallization strategy introducing combined Cu and Nb addition is not a suitable alternative to facilitate nanocrystallization of cast-iron-based bulk metallic glasses.