Leonardus Bimo Bayu Aji | 20-FS-004
The goal of this project was to establish the scientific basis for subtractive manufacturing (sculpting) of porous materials using ion beams. Using the catcher foil technique in combination with molecular dynamics simulations, we studied the dependence of the sputtering yield of silver and gold nanofoams as a function of foam monolith density, ion mass, and the beam incidence angle, and compared these dependencies to those measured for full-density solids. We found that the foam sputtering yield was considerably lower than for the full-density solid. The sputtering yield increased with beam incidence angle, and the open structure of the foam suppressed the development of collision cascades. We also found that the sputtering yield exhibits a weak dependence on foam density. The simulation revealed a significant redeposition of sputtered atoms in the foam.
This project supports the Laboratory’s core competencies in advanced materials and manufacturing and high-energy-density (HED) science. We assessed the feasibility of using ion beams to micro-machine nanofoams to enable future HED and inertial confinement fusion (ICF) experiments, enhancing capabilities that meet enduring mission needs. While this process produces complex, surface-level, microstructural changes that are undesirable for HED/ICF applications, it could be useful for sculpting specific nanofoams or for applications requiring spike-like surface morphology.