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arXiv · 2412.14557

Effect of molar volume of diffusing elements and cross terms of Onsager formalism (vacancy wind effect) on estimated diffusion coefficients in ternary and multicomponent solid solutions

Aloke Paul
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Abstract

The correlation between intrinsic and tracer diffusion coefficients considering the molar volume of the diffusing elements and cross phenomenological constants of Onsager contributing to the vacancy wind effect in ternary and multicomponent systems. Manning established this correlation assuming constant molar volume. The difference in data calculated considering a constant molar volume and neglecting the vacancy wind effect, which is mainly practised until today, is compared with the data considering the molar volume of diffusing elements and vacancy wind effect in NiCoFeCr and an imaginary quaternary multi-principal element system. This indicates a significant error in estimated data when considering a constant molar volume if the molar volumes of the diffusing elements are reasonably different. Therefore, the outcome of this study is expected to bring a significant change in diffusion analysis in ternary and multicomponent systems.

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Aloke Paul. 2025-02-04. Effect of molar volume of diffusing elements and cross terms of Onsager formalism (vacancy wind effect) on estimated diffusion coefficients in ternary and multicomponent solid solutions. https://arxiv.org/abs/2412.14557

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