Exploring defect-induced deformation in polymeric microlattices using laboratory-based X-ray nanotomography

Abstract

Defects introduced during additive manufacturing strongly influence the mechanical response of architected materials, yet their evolution under load is difficult to resolve at the micrometer scale. Laboratory-based X-ray nanotomography (nanoCT) at 128 nm voxel size was used here to image tetrahedral polymeric microlattices, printed defect-free and with three omitted beams, during in situ compression. Image registration yielded three-dimensional displacement fields, and finite element simulations reproduced the measured behavior. Displacement was markedly reduced at the defect and recovered in neighboring unit cells, with an accompanying stiffness reduction. Laboratory nanoCT thus provides a practical route to validate models of architected materials.