Nuclear thermal propulsion (NTP), which may utilize cermet fuels, shows promise in improving the feasibility of long-distance space travel. These cermet fuels are composed of a ceramic nuclear fuel phase, such as UO₂ or UN, and a protective refractory metal (W or Mo) phase. In this work, a material system consisting of tungsten-yttria stabilized zirconia (W-YSZ) surrogate fuel elements were fabricated via spark plasma sintering. Prior to consolidation, magnetron sputtering was utilized to provide conformal W coatings to the YSZ particles, such coatings were 80 to 550 nm in thickness. These coatings, when excess W powder was added, were found to reduce the ceramic-ceramic contacts as well as improve the densification of the cermet over powders that were not coated. Furthermore, when the coating thickness was at least 350 nm, and additional W powder added to yield a metallic fraction of 32 vol.%, the ceramic-ceramic contacts remained nearly identical to higher W fractions. This suggests that conformal coated ceramic fuel particles would reduce the necessary amount of refractory metal matrix, which in turn would reduce neutron poisoning, lower fuel element weight, and increase fissile fuel content from the 60 vol.% fuel in conventional NTP cermets.

可以使用金属陶瓷燃料的核热推进 (NTP) 在提高长距离太空旅行的可行性方面显示出前景。这些金属陶瓷燃料由陶瓷核燃料相组成，例如 UO ₂或 UN，以及保护性难熔金属（W 或 Mo）相。在这项工作中，通过放电等离子烧结制造了由钨-氧化钇稳定氧化锆 (W-YSZ) 替代燃料元件组成的材料系统。在固结之前，利用磁控溅射为 YSZ 颗粒提供共形 W 涂层，这种涂层的厚度为 80 至 550 nm。发现当加入过量钨粉时，这些涂层会减少陶瓷与陶瓷的接触，并提高金属陶瓷的致密性，而不是未涂覆的粉末。此外，当涂层厚度至少为 350 nm，并添加额外的 W 粉末以产生 32 vol.% 的金属分数时，陶瓷-陶瓷触点几乎保持与更高的 W 分数相同。