Mechanics of 3D printed metamaterials

Octet failure

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

Description

Selective laser melting (or SLM) is an additive manufacturing method that allows for the creation of metallic lattices. However, this manufacturing method causes several deviations from the as-designed geometry to 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.

Our research involves trying to better understand these mechanical issues by using techniques such as probabilistic models 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

Dallago M, Raghavendra S, Luchin V, Zappini G, Pasini D, Benedetti M, The role of node fillet, unit-cell size and strut orientation on the fatigue strength of Ti-6Al-4V lattice materials additively manufactured via Laser Powder Bed Fusion, International Journal of Fatigue, Vol 142, 105946, 2021. PDF_logo

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, Vol. 35(15), pp. 1900-1912 , 2020. Invited. PDF_logo

Dallago M, Raghavendra S, Luchin V, Zappini G, Pasini D, Benedetti M, Geometric assessment of lattice materials built via Selective Laser Melting, Materials Today, Vol 7, pp. 353, 2019.PDF_logo

Liu L, Kamm P, GarciĀ­a-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. PDF_logo

Bagheri ZS, Melancon D, Liu L, Johnston RB, Pasini D, Compensation Strategy to Reduce Geometry and Mechanics Mismatches in Porous Biomaterials Built with Selective Laser Melting, Journal of the Mechanical Behavior of Biomedical Materials, Special issue on the Mechanics of Additively Manufactured Biomaterials and Implants, Vol. 70, pp. 17, 27, 2017. PDF_logo