Aluminum lattice structures processed by additive manufacturing: Mechanical and microstructural characterization

Lattice structures are lightweight materials very interesting for their mechanical performances. Thanks to the developpment of new additive manufacturing technologies, these structures are faster and cheaper to produce than with other classical manufacturing processes. More specifically, selective laser melting (SLM) allows the creation of lattice structures in aluminium alloy. The objective of this project is to study the microstructure and the mechanical properties of AlSi10Mg lattice produced by SLM. Firstly, the idea is to characterize the effect of the geometry and the post-heat treatments on the microstructure and the hardness of one unit lattice cell. Then, the tensile, compressive and impact responses of the lattice are analaysed. Results show that different scales of heterogeneities appear in the lattice microstructure. They can be erased by heat treatment. However, the application of a heat treament changes the mechanical properties and leads to a softening of the structure.