Extending the Passive Region of CrFeNi‐Based High Entropy Alloys

Abstract: This study provides principles for designing new corrosion resistant high entropy alloys. The theoretical framework is a percolation model developed by Newman and Sieradzki that predicts the ability of an alloy to passivate, i.e., to form a protective surface oxide, based on its composition. Here, their model is applied to more complex materials than previously, namely amorphous CrFeNiTa and CrFeNiW alloys. Furthermore, the model describes a more complex passivation process: reforming the oxide layer above the transpassive potential of Cr. The model is used to predict the lowest concentration of Ta or W required to extend the passive region, yielding 11–14 at% Ta and 14–17 at% W. For CrFeNiTa, experiments reveal a threshold value of 13–15 at% Ta, which agrees with the prediction. For CrFeNiW, the experimentally determined threshold value is 37–45 at% W, far above the predicted value. Further investigations explore why the percolation model fails to describe the CrFeNiW system; key factors are the higher nobility and the pH sensitivity of W. These results demonstrate some limitations of the percolation model and offer complementary passivation criteria, while providing a design route for combining the properties of the 3d transition metal and refractory metal groups.

Angaben zum Objekt

• Standort: Deutsche Nationalbibliothek Frankfurt am Main
• Umfang: Online-Ressource
• Sprache: Englisch

Verweise und Beziehungen

• Erschienen in: Extending the Passive Region of CrFeNi‐Based High Entropy Alloys ; day:11 ; month:09 ; year:2023 ; extent:19 ; Advanced functional materials ; (11.09.2023) (gesamt 19)

Beteiligte, Orts- und Zeitangaben

• Urheber: Zendejas Medina, León ; Mølmen, Live ; Paschalidou, Eirini‐Maria ; Donzel‐Gargand, Olivier ; Leisner, Peter ; Jansson, Ulf ; Nyholm, Leif

Weitere Informationen

• DOI: 10.1002/adfm.202307897
• URN: urn:nbn:de:101:1-2023091215115007668526
• Rechteinformation: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Letzte Aktualisierung: 14.08.2025, 10:45 MESZ