PSI - Issue 68

Shiyu Suzuki et al. / Procedia Structural Integrity 68 (2025) 596–602 S. Suzuku, N. Tsushima / Structural Integrity Procedia 00 (2025) 000–000

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1. Introduction An additively manufactured (AM) aluminum alloy, AlSi10Mg, is one of the most extensively used AM materials in automotive and aerospace industries owing to its excellent property of the strength-to-weight ratio (Zhao et al., 2022, Michi et al., 2022). The AM technology also has found a way to further pursue the alloy’s lightweight performance via building lattice structures by taking advantage of its high freedom of three-dimensional printing (Blakey-Milner et al., 2021). Numerous studies have been conducted to investigate mechanical properties including tensile, compressive and fatigue properties of AlSi10Mg (Wu et al., 2016, Uzan et al., 2018, Ngnekou et al., 2019, Wu et al., 2025) and its lattice structures (Gavazzoni et al., 2022, Boniotti et al., 2022). However, most of them have focused on the phenomena at room temperature (RT), and investigations on effects of different temperatures have been limited. This study investigates the effect of the temperature on tensile and fatigue properties of AlSi10Mg lattice structures fabricated by

AM from -60 °C to 200 °C. 2. Experimental procedures 2.1. Materials and specimens

An aluminium alloy, AlSi10Mg, was used in this study. The laser powder bed fusion (L-PBF) was employed to manufacture specimens for the mechanical tests. A machine used for the manufacture was EOS M 290. Process parameters were as follows: laser power was 370 W, layer thickness was 30 μm, spot size was 80 μm, platform temperature was 200 °C. All specimens were heat treated at 200 °C for 4.5 hours to relieve the residual stress. Two types of specimens were manufactured and tested in this study. One is a cylindrical specimen for the standard fatigue test of the bulk material. The dimensions of the cylindrical specimen are compliant with ASTM E466-21 (2021) and shown in Fig. 1(a). The other type of the specimens is a lattice specimen for the tensile and fatigue tests of the lattice structure. The dimensions are show in Fig. 1(b). The lattice specimen consists of simple cubic unit cells shown in Fig. 1(b). The size of the unit cell is 3 mm × 3 mm × 3 mm, and the width of struts was 0.5 mm. The ratio of the mass of the unit cell to the bulk material was 0.26. The gauge section of the lattice specimen contains 6 unit cells in the loading direction and 10 unit cells in directions perpendicular to the loading direction. Also, there are additional three layers of the unit cells with gradient strut widths at each of the top and bottom side of the gauge section to reduce stress concentrations between the bulk material and lattice structure. All of the cylindrical and lattice specimens were manufactured on the same build platform and were built in the vertical direction. Fig. 1. (a) Cylindrical specimen; (b) Lattice specimen and unit cell; (c) Experimental set-up.