The melt-spun Ni-25Al-xFe ribbons were used to investigate the rapidly solidified effect on hardness and microstructures. The results revealed that the phases existing in these ribbons were the same as the ingot-casting specimens, but the interdendritic regions were suppressed by rapid solidification, and the volume fraction of gamma phase decreased. In addition, the rapidly solidified technique was found to increase the hardness significantly. The maximum increment of 250 DPH (from HV400 to HV650) was found in the Ni-25Al-30Fe because of the effects of the suppression of the second phase formation and the size refinement. (C) 2001 Elsevier Science Ltd. All rights reserved