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arXiv · 1302.1708

Studies of atomic diffusion in Ni-Pt solid solution by x-ray photon correlation spectroscopy

Markus Stana·Michael Leitner·Manuel Ross·Bogdan Sepiol
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Abstract

Atomic scale x-ray photon correlation spectroscopy (aXPCS) was used to study atomic diffusion in the Ni97 Pt3 solid solution with both a single crystal and a polycrystalline sample. Different jump diffusion models are discussed using experimental results and Monte Carlo simulations. The sensitivity of aXPCS experiments to short-range order (in this case governed by a strong Pt-Pt repulsive force) is demonstrated. The activation energy of 2.93(10) eV as well as diffusivities in the range of 10-23 m2 s-1 at 830 K agree very well with the results of tracer diffusion studies at much higher temperatures.

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Markus Stana, Michael Leitner, Manuel Ross, Bogdan Sepiol. 2013-02-07. Studies of atomic diffusion in Ni-Pt solid solution by x-ray photon correlation spectroscopy. https://doi.org/10.1088/0953-8984%2F25%2F6%2F065401

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