The proposed innovation is a new fuel element design that involves a stack of grooved disks, where propellant can flow along the grooves. This design increases surface area in contact with propellant, leading to higher heat transfer, engine efficiency, and propellant temperatures. Higher thrust-to-weight ratios are also possible, and the design can also alleviate some of the manufacturing hurdles that exist with hexagonal elements. The approach is to (1) determine viable compositions of representative grooved disk prototypes, (2) evaluate fabrication processes through the manufacture of prototype disks, and (3) characterize the microstructure of these disks. This project will also evaluate the feasibility of incorporating advanced carbide fuels into NTR reactor designs.