Experimental D-T Ice-Layering Target Assembly

Inertial confinement fusion ignition experiments in the National Ignition Facility require a capsule containing deuterium-tritium fuel at cryogenic temperatures. To better understand how to produce and control the required uniform fuel ice layer, experimental layering targets are fabricated and assembled to be dimensionally similar to the ignition targets and vacuum leaktight at 18 K. Low production yield of these targets demanded a more quantitative understanding of the interfacial behavior of bonded joints and required the development of more deterministic assembly methods. Each sealing joint was individually analyzed, and target components, assembly processes, and tooling were modified as needed to make robust leaktight targets. The function, design, and assembly methods of experimental layering targets are described.