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Studies the anisotropic grain growth of delta-NiMo intermetallic compound during the annealings of Mo/Ni thin film diffusion couples. Generation of layered microstructures showing median-sized, equiaxed grains and large columnar single crystalline grains; Growth direction of the columnar grains.

We provide direct experimental evidence for a nonrandom distribution of atomic constituents in Zr[sub 52.5]Ti[sub 5]Al[sub 10]Cu[sub 17.9]Ni[sub 14.6] bulk metallic glass using positron annihilation spectroscopy. The Ti content around the open-volume regions is significantly enhanced at the expense of Ni and Cu. Our results indicate that Ni and Cu atoms closely occupy the volume bounded by their neighboring atoms while Al, Ti, and Zr are less closely packed, and more likely to be associated with the open-volume regions. The overall distribution of elements seen by the positron is not significantly altered by annealing or by crystallization. Theoretical calculations indicate that the observed elemental distribution is not consistent with the known crystalline phases Zr[sub 2]Cu and NiZr[sub 2], while Al[sub 3]Zr[sub 4] shows some of the characteristics seen in the experiment. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]