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arXiv · 2002.05497

Consistency Check of Segregation Energies of Elements at Ni and Fe Grain-Boundaries

Wilfried Wunderlich
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Abstract

The need for advanced functional materials is expected to provide a boost in powder metallurgy, where the impurities on powder surfaces is incorporated as at grain boundary segregation. This paper has three aims. First, we analyze whether the reported data of Ni and Fe hosts can be correlated to basic thermodynamic data on chemical elements. The second aim is the consistency check, which is suggested to be applied for any data base. The third aim, is whether information of 50 most important elements can give additional information for prediction of unknown data. The data are analyzed whether a set of basic data is sufficient for characterizing the segregation. The data of the solvents were analyzed using the software R for principal component analysis (PCA). We grouped and correlated the data to Mendeleev number and thermodynamic data on pure elements. As a result, we found that the embrittlement depends strongly on the chemical bonding, but weakly on mechanical factors. Surprisingly, the geometry of the grain boundary type such as interlayer distances, and local atomic volumes has only a minor influence.

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Wilfried Wunderlich. 2020-02-13. Consistency Check of Segregation Energies of Elements at Ni and Fe Grain-Boundaries. https://doi.org/10.4028/www.scientific.net%2Fmsf.1016.1642

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