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Thermodynamics of Materials in Extreme Environments: Poster Session
Sponsored by: ACerS Basic Science Division, ACerS Energy Materials and Systems Division
Program Organizers: Xiaofeng Guo, Washington State University; Kristina Lilova, Arizona State University; Kyle Brinkman, Clemson University; Alexandra Navrotsky, Arizona State University; Jake Amoroso, Savannah River National Laboratory; Xingbo Liu, West Virginia University; Gustavo Costa, NASA Glenn Research Center

Tuesday 12:00 PM
October 19, 2021
Room: Exhibit Hall B
Location: Greater Columbus Convention Center

Session Chair: Kristina Lilova, Arizona State University; Xiaofeng Guo, Washington State University

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Poster
P2-19: Design of Ultra-high Temperature Ceramics for Oxidation Resistance: Niquana S¹; Elizabeth Opila Opila¹; ¹University of Virginia
    Ultra-high temperature ceramics (UHTCs) are capable of withstanding extreme temperatures above 2500°C. Specifically, hafnium carbide (HfC) and tantalum carbide (TaC) have the highest melting points amongst UHTCs, however, rapid oxidation of these materials is a persistent problem. In this work, the oxidation of pure HfC and TaC was studied at 1400°C in 1% oxygen/argon for times up to 10 minutes. These oxidation results demonstrated that pure TaC oxidizes more rapidly than pure HfC. In situ oxidation was also conducted at the Argonne National Lab Advanced Photon Source, in 0.06 % oxygen/argon. Results showed more formation of protective Hf6Ta2O17 for 6HfC-4TaC compared to 9HfC-1TaC. The results obtained from these experiments demonstrate steps closer to obtaining an optimal oxidation resistant UHTC.

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