Meso-Scale Simulations of the Deformation in Additively Manufactured 316L Stainless Steel Lattices Characterized with in-situ X-ray Phase Contrast Imaging*

Additive manufacturing (AM) has enabled the realization of topologically optimized lattice architectures for lightweight structural components that provide superior mechanical properties and energy absorption capabilities compared to bulk materials and yet the property-to-performance relationship of these structures at high strain rates have not been experimentally characterized, therefore limiting the development of mesoscale modeling techniques to further understand the constitutive response of metallic lattices. Here, we present a methodology to parameterize the constitutive response of metal lattice architectures through coupling detailed mesoscale simulations that incorporate an as-built lattice characterized by computed tomography (CT) to shock compression experiments combined with in-situ x-ray phase contrast imaging (PCI). We compare PCI images to simulated radiographs generated from the mesoscale simulations to investigate the influence of the constitutive parameters for an octet lattice impacted in a velocity range of 0.8 – 1.2 km/s. The coupled approach offers a more robust method to validate and optimize constitutive properties in AM metal lattices through direct comparison of the transient deformation states and can be extended to other AM architectures.