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Direct observations of nucleation in a nondilute multicomponent alloy

Chantal K. Sudbrack·Ronald D. Noebe·David N. Seidman
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Abstract

The chemical pathways leading to gamma-prime(L1_2)-nucleation from nondilute Ni-5.2 Al-14.2 Cr at.%, gamma(f.c.c.), at 873 K are followed with radial distribution functions and isoconcentration surface analyses of direct-space atom-probe tomographic images. Although Cr atoms initially are randomly distributed, a distribution of congruent Ni3Al short-range order domains (SRO), =0.6 nm, results from Al diffusion during quenching. Domain site occupancy develops as their number density increases leading to Al-rich phase separation by gamma-prime-nucleation, =0.75 nm, after SRO occurs.

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Chantal K. Sudbrack, Ronald D. Noebe, David N. Seidman. 2006-02-23. Direct observations of nucleation in a nondilute multicomponent alloy. https://doi.org/10.1103/physrevb.73.212101

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