New Insights into the High-temperature Oxidation Behavior of (TiZrHfTaNb)C High-entropy Carbide

Abstract

High-entropy carbide (HEC) (TiZrHfTaNb)C was synthesized via spark plasma sintering using carbide powders prepared through carbothermic reduction with various carbon sources. Among the HEC samples, those fabricated with graphitic carbon microspheres exhibited superior high-temperature oxidation resistance, characterized by lower mass change rates and fewer surface defects compared to samples made with carbon black, carbon microspheres, and flake graphite. The oxidation behavior was significantly influenced by oxygen concentration (11–41 vol%), which affected the phase composition, microstructure, and physical properties. Higher oxygen levels reduced the oxidation activation energy, increased oxide phase formation, and altered the specific surface area through a sequence of growth and reduction. Oxycarbide phases ((TaNbTi)CxO1-x) formed during oxidation reacted further at higher oxygen concentrations, generating metal oxides and microdefects that eventually merged into larger cracks and pores. These findings provide insights into the mechanisms governing oxidation resistance in HECs.

Department(s)

Materials Science and Engineering

Comments

National Natural Science Foundation of China, Grant 12305296

Keywords and Phrases

High-entropy carbide; Microstructure; Oxidation behavior; Oxidation kinetics; Oxygen concentration

International Standard Serial Number (ISSN)

2213-3917; 0263-4368

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2025 Elsevier, All rights reserved.

Publication Date

01 Apr 2025

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