A multiscale comparison of stochastic open-cell aluminum foam produced via conventional and additive-manufacturing routes

With the exciting potential of additive manufacturing of metals to produce geometrically complex structures come many unknowns and uncertainties regarding the process-microstructure-property relationships of the additively manufactured (AM) parts, especially in comparison to their conventionally manufactured counterparts. This work attempts to elucidate some key differences between AM and cast parts by conducting a multiscale comparison of samples that are intended to be identical, except for the route by which each was manufactured. The samples of interest are open-cell foams of an Al-Mg-Si alloy (Al 6061). The baseline open-cell foam is conventionally produced via investment casting. Copies are produced using laser powder bed fusion. Full-field deformation is characterized under compressive loading using in-situ X-ray computed tomography. The foams are compared in terms of global load versus displacement response, local failure mechanisms, and characteristics of the grain structure.