Fabrication of Pressurized 2 mm Beryllium Targets for ICF Experiments

We have successfully fabricated 2 mm beryllium targets pressurized with a gas mixture of ~20 atm deuterium and ~0.1 atm argon. These targets have been used for indirect drive Inertial Confinement Fusion (ICF) experiments on the Z-pinch machine at Sandia National Laboratories leading to record neutron yields of ~3.5 × 10¹¹ [J.E. Bailey, et al., "Be Capsule Implosions Driven by Dynamic Hohlraum X-rays," Bull. Am. Phys. Soc. 51, 107 (2006)]. This paper will discuss the process of fabricating such targets from intact shells (Be sputter coated CH mandrels). These processes include laser drilling a ~6 m diameter fill hole in a shell, removing the CH mandrel by pyrolysis, pressurizing the target with a deuterium/argon gas mixture and sealing the fill hole using UV glue while under pressure. The targets were characterized for gas pressure and deuterium gas permeation half-life by utilizing techniques including mass spectrometry, x-ray fluorescence spectroscopy and controlled shell bursting.