Thermal properties of HfN-MoW surrogate cermet fuel for nuclear thermal propulsion

The thermal properties of MoW-HfN, a surrogate cermet for MoW-UN nuclear thermal propulsion fuel, were characterized over a wide range of elevated temperatures. Thermal diffusivity, coefficient of thermal expansion (CTE), and heat capacity were measured. Optical and scanning electron microscopy were performed to characterize the microstructure and draw structure-property correlations. The thermal diffusivity was obtained using the laser flash method. Diffusivity values ranged from about 0.18 cm(2)/s at 200 degrees C to 0.15 cm(2)/s at 1800 degrees C. The CTE was measured using push-rod dilatometry up to 1600 degrees C, giving values between 6.0 and 9.0 mu m/m. A scientific rationalization of the effective material properties is made using the rule-of-mixtures and other effective properties models.

Automated summary

In this study, the thermal properties of MoW-HfN, a surrogate cermet for MoW-UN nuclear thermal propulsion fuel, were characterized. The thermal diffusivity, coefficient of thermal expansion (CTE), and heat capacity were measured, and the microstructure was analyzed using optical and scanning electron microscopy. The study provided important insights into the structure-property correlations of the material.