In majority of independent reviews conducted over the last fifty years, Nuclear Thermal Propulsion (NTP) hasbeen identified as a critical technology need for NASA's deep space human exploration. NASA's advancedExploration Systems (AES) Nuclear Cryogenic Propulsion Stage (NCPS) project is focusing on the furtherdevelopment of NTP. Main advantages of NTP include a higher thrust to weight ratio and higher specific impulsecompared to current liquid propulsion systems. With the completion of the major NTP programs of the 1950's and60's, little progress has been made on any sustained fuel development work that appreciably contributed to fuelfabrication data. It is important to revisit fuel fabrication technologies to deploy more advanced processes to developsuccessful NTP fuels. CERMET fuels, specifically W-UO2, are of particular interest to future NTP development forthese advantages: (1) High melting temperatures (2) Ability to accommodate a large fission product inventory duringirradiation (3) Compatibility with flowing hot hydrogen when coated. We employ Hot Isostatic Pressing (HIP),Chemical Vapor Deposition (CVD), and Plasma Spheroidization system (PSS) for the fabrication of CERMET fuels.Using the Nuclear Thermal Rocket Element Environmental Simulator (NTREES) for testing and analysis ofsurrogate materials, we study the effects of thermal cycling on the fuel element. Then, we optimize the fabrication ofCERMET fuel by: (1) Investigating HIP parameters: run time and temperature (1600 °C – 1900 °C) (2) Testingsurrogate materials, Zirconium oxide (ZrO2), for the relationship between particle size and consolidation properties(3) Analyzing coated and uncoated fuel particles for their properties. The need for NTP is not specific just for NASAapplications, but for any and all international interplanetary or deep space mission.
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