Friction stir additive manufacturing of regolith metal matrix composite

Abstract

In this work, a metal matrix composite of AA6061 – 20 wt% regolith simulant was deposited into a 50 mm tall × 147 mm long × 45 mm wide build using additive friction stir deposition (AFSD). In situ resource utilization plays a vital role in the development of the self-sustaining future space infrastructure in implementing an efficient use of the lunar environment material. Using x-ray computed tomography, the build was evaluated for porosity, which measured 0.03 %, and was noted to be in the initial deposit layer as well as near the outer surface. Tensile behavior were evaluated in the build and longitudinal direction, with the longitudinal direction having 40 % higher yield strength than the build direction. However, in either direction, the strength was higher than that of as-deposited AFSD AA6061 with no particulates, but at the expense of ductility. This work quantifies the utility of incorporating hard, secondary particulates from potential point-of-need resources into a metal for extraterrestrial exploration.