Additively manufactured AlSi10Mg lattices – Potential and limits of modelling as-designed structures. (August 2022)

• Record Type: Journal Article
• Authors: Gebhardt, Ulrike; Gustmann, Tobias; Giebeler, Lars; Hirsch, Franz; Hufenbach, Julia Kristin; Kästner, Markus
• Is Part Of: Materials & design. Volume 220(2022)
• Publication Date: 2022-08
• Subjects: Additive manufacturing -- Lattice structures -- Material characterisation -- Al-based alloy -- Elastic–plastic material model -- Experimental characterisation; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2022.110796
• Languages: English
• ISSNs: 0264-1275

Abstract

Graphical abstract: Highlights: As-built and heat-treated AlSi10Mg specimen are used to parametrise a material model. Microstructural analyses explore the mechanical behaviour of bulk and lattices. Lattices are experimentally investigated in compression, tension, torsion and shear. The elastic–plastic material model predicts the mechanical behaviour of lattices. Powder, process parameters and geometry influence porosity and surface quality. Abstract: Additive manufacturing overcomes the restrictions of classical manufacturing methods and enables the production of near-net-shaped, complex geometries. In that context, lattice structures are of high interest due to their superior weight reduction potential. AlSi10Mg is a well-known alloy for additive manufacturing and well suited for such applications due to its high strength to material density ratio. It has been selected in this study for producing bulk material and complex geometries of a strut-based lattice type (rhombic dodecahedron). A detailed characterisation of as-built and heat-treated specimens has been conducted including microstructural analyses, identification of imperfections and rigorous mechanical testing under different load conditions. An isotropic elastic–plastic material model is deduced on the basis of tension test results of bulk material test specimens. Performed experiments under compression, shear, torsion and tension load are compared to their virtual equivalents. With the help of numerical modelling, the overall structural behaviour was simulated using the detailed lattice geometry and was successfully predicted by the presented numerical models. The discussion of the limits of this approach aims to evaluate the potential of the numerical assessment in the modelling of the properties for novel lightweight structures.