Effect of Cell Geometry and Heat Treatment on the Energy Absorption Property of AlSi10Mg Alloy Lattice Structures Produced by Laser-Based Powder Bed Fusion

In the present study, microstructural characteristics, compression behavior and energy absorption property of AlSi10Mg Octet Truss, FCC and Tetra lattice structures with volume fraction of 30%, 50%, and 70% produced using Laser-based powder bed fusion (L-PBF) method have been investigated. Proper selection of processing parameters for L-PBF enables high internal and surface quality even though node and strut in the lattice structure are very thin. AlSi10Mg lattice structure consists of a cellular structure composed of α-Al and intercellular eutectic Si. With heat treatment, needle shape Mg 2 Si precipitates in the α-Al matrix. Octet Truss, FCC and Tetra lattice structures show similar compression fracture behavior. The maximum fracture forces for Octet Truss, FCC and Tetra lattice structures (70% volume fraction) are 22.0 kN, 23.7 kN and 23.7 kN, respectively, while the energy absorption values up to 8 mm displacement are 128.1 J, 126.0 J and 88.9 J, respectively. With heat treatment, the maximum fracture force and the absorbed energy decreased when compared to those in as-built condition. When considering application of AlSi10Mg alloy lattice structure in shock absorbing part, FCC lattice structure with 70% volume fraction exhibits the most optimum combination of mechanical property and shock absorption characteristics. Graphical Abstract