Synthesis, Characterization, and Properties of Nanometer-Sized Intermetallics

摘要

Nanocrystalline intermetallics were produced from pre-cast NiAl using electronbeam inert gas condensation system. A liquid nitrogen cooled cold finger was used to collect the powder. After collection, the powder was transported under high vacuum to a compaction unit where in-situ compaction at 1.4 Gpa was carried out under vacuum conditions at temperatures ranging from 100 to 300C. Energy dispersive spectroscopy and X-ray diffraction (XRD) techniques were used to investigate chemical composition, phase, and grain size. Average grain size in the range of 2 to 10 nm was found for various specimens. XRD spectra of as consolidated specimens suggested a majority of ordered phase with little disordering in n-NiAl.