| The nanocrystalline powders with stoichiometric Ni3Al composition were prepared by ball milling of AlNi or Al3Ni2 intermetallics with addition of Ni powder. The phase and structural changes occurring in the materials during mechanical alloying and during subsequent heating in a calorimeter were investigated with the use of X-ray diffraction. It was found that for both initial powder mixtures at the first stage of the mechanical alloying process, a supersaturated Ni(Al) solid solution was formed, and this phase remained as the only milling product. Upon heating of these powders in the calorimeter, the Ni(Al) solid solution transformed into the ordered Ni3Al intermetallic compound. The microstructure of the Ni3Al intermetallic compound was examined using transmission electron microscopy. |
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