Wetted foam target production for Inertial Fusion Energy*

Production of wetted foam capsules for inertial fusion energy (IFE) is priority research opportunity listed in the DOE Basic Research Needs for IFE workshop report¹. A wetted foam target typically consists of or includes a spherical polymer shell with a layer of low-density polymer foam just inside the shell. The foam layer would be used to wick in and create a layer of liquid DT filling the foam.

We are developing spherical foam shells with density ≤50mg/cm³. Two different approaches to the manufacture of these shells are being pursued: microencapsulation and additive manufacturing via two photon polymerization (2PP). We report on our progress towards making the low-density foam shells by these two approaches.

Initial work to prepare dicyclopentadiene (DCPD) foam for micro-encapsulation will be discussed. Methods for deterministic symmetry control in micro-encapsulated capsules/foam shells will also be outlined.

*Portions of the presented work were performed under General Atomics Internal R&D funding and portions receive funding from the DOE FES IFE-STAR hubs STARFIRE and RISE.