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arXiv · 2003.09474

Experimental and theoretical study of tracer diffusion in a series of (CoCrFeMn)$_{100-x}$Ni$_x$ alloys

Josua Kottke·Daniel Utt·Mathilde Laurent-Brocq·Adnan Fareed·Daniel Gaertner·Loic Perriere·Lukasz Rogal·Alexander Stukowski·Karsten Albe·Sergiy V. Divinski·Gerhard Wilde
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Abstract

Tracer diffusion of all constituting elements is studied at various temperatures in a series of (CoCrFeMn)$_{100-x}$Ni$_x$ alloys with compositions ranging from pure Ni to the equiatomic CoCrFeMnNi high-entropy alloy. At a given homologous temperature, the measured tracer diffusion coefficients change non-monotonically along the transition from pure Ni to the concentrated alloys and finally to the equiatomic CoCrFeMnNi alloy. This is explained by atomistic Monte-Carlo simulations based on a modified embedded-atom potentials, which reveal that local heterogeneities of the atomic configurations around a vacancy cause correlation effects and induce significant deviations from predictions of the random alloy model.

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Josua Kottke, Daniel Utt, Mathilde Laurent-Brocq, Adnan Fareed, Daniel Gaertner, Loic Perriere, Lukasz Rogal, Alexander Stukowski, Karsten Albe, Sergiy V. Divinski, Gerhard Wilde. 2020-03-20. Experimental and theoretical study of tracer diffusion in a series of (CoCrFeMn)$_{100-x}$Ni$_x$ alloys. https://arxiv.org/abs/2003.09474

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