Failure Mechanisms in Metallic Lattices

Octet failure

In-situ tomography response of AlSi10Mg octet sample under compression with sequential frames showing failure evolution

Description

We unveiled the damage evolution and failure mechanisms of metallic lattices fabricated with selective laser melting. Due to the manufacturing process, several deviations from the as-designed geometry appear, thereby leading to a major discrepancy between the theoretical and computational predictions of as-designed samples and the testing measurements of as-built samples. To understand the culprit, we developed probabilistic models (based on both homogenized schemes and full-scale simulations) that capture the location, morphology and distribution of defects in as-built samples. From these results, we can gauge the impact of manufacturing constraints on additively fabricated samples of alternative cell topology.

Relevant Publications

Liu L, Kamm P, García-Moreno F, Banhart J, Pasini D, Elastic and failure response of imperfect three-dimensional metallic lattices: the role of geometric defects induced by Selective Laser Melting, Journal of the Mechanics and Physics of Solids, Vol 107, pp. 160-184, 2017.

El Elmi A, Melancon D, Asgari M, Pasini D, Experimental and numerical investigation of SLM induced defects in Ti-6Al-4V octet truss lattice material: the role of material microstructure and morphological variations, Journal of Materials Research – Focus Issue: Additive Manufacturing of Metals: Complex Microstructures and Architecture Design, 1-13, 2020