Accession Number : ADA320458

Title :   Synthesis, Characterization, and Properties of Nanometer-Sized Intermetallics.

Descriptive Note : Final rept. 1 Jul 92-31 Jul 95,

Corporate Author : ILLINOIS INST OF TECH CHICAGO DEPT OF METALLURGICAL AND MATERIALS ENGINEERING

Personal Author(s) : Dollar, Marek ; Choudry, Mahmood S.

PDF Url : ADA320458

Report Date : SEP 1995

Pagination or Media Count : 81

Abstract : Nanocrystalline intermetallics were produced from pre-cast NiAl using electron beam 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.

Descriptors :   *INTERMETALLIC COMPOUNDS, TEMPERATURE, SPECTROSCOPY, SYNTHESIS, PHASE TRANSFORMATIONS, POWDERS, X RAY DIFFRACTION, VACUUM, ORDER DISORDER TRANSFORMATIONS, GRAIN SIZE, CHEMICAL COMPOSITION, ELECTRON BEAMS, NICKEL, LIQUID NITROGEN, CONDENSATION, COMPACTING, ALUMINIDES, HIGH VACUUM.

Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Crystallography
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE