AMORPHIZATION OF NI AND HF POWDERS BY MECHANICAL ALLOYING

Mixed Ni and Hf powders with the composition of NiHf2 have been mechan ically alloyed by the planetary ball mill. The transformation of the c rystalline powders into amorphous ones has been investigated with X-ra y difraction, time differential perturbed angular correlation and diff erential scanning calorimetry. The thermal stability and the structura l characteristics of amorphous phase in powders milled for a given tim e have been examined by a comparison with melt-spun NiHf2 amorphous al loy.