Resilience of uranium mononitride/zirconium carbide composites and uranium-zirconium carbonitride in hot hydrogen for nuclear thermal propulsion

• Published in: Journal of nuclear materials 2024-08, Vol.596 (C), p.155101, Article 155101
• Main Authors: Hamilton, Sarah R., Zillinger, James, Scott, Randall, Jerred, Nathan, Palomares, Kelsa, Salasin, John, Miller, Victoria M.
• Format: Article
• Language: English
• Subjects: Ceramic composite; Corrosion; Hot hydrogen; Nuclear thermal propulsion; Uranium nitride; Uranium-zirconium carbonitride; Zirconium carbide
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2024.155101

Nuclear thermal rockets require fuels capable of withstanding flowing hydrogen propellant up to 3200 K. Presently, there has not been a fuel type that reliably operates at these conditions. A promising candidate anticipated to endure this demanding environment is a ceramic-ceramic composite comprising of uranium mononitride and zirconium carbide. This investigation assesses the behavior and resilience of variations of this composite and its resultant homogenized form (uranium-zirconium carbonitride) under two hot hydrogen conditions (2273 K and 3000 K). The findings revealed that composites that homogenize into UZrCN exhibit superior structural integrity in hydrogen compared to heterogeneous counterparts. Consequently, this study underscores the potential of homogenized uranium-zirconium carbonitride for enhanced performance in nuclear thermal propulsion applications. •This study explores the behavior of cercer composite fuels of UN/ZrC in hot hydrogen.•Homogenized UZrCN exhibited improved structural integrity under these tests.•These results imply that fuel homogenization could be vital to surviving hot hydrogen.•The samples' failure modes exhibit the susceptibility of the composites to cracking.