PSI - Issue 82

Katarina Monkova et al. / Procedia Structural Integrity 82 (2026) 107–111 Katarina Monkova et al. / Structural Integrity Procedia 00 (2021) 000–000

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its physical or mechanical properties, that subsequently conveys benefits in the form of saving material for the production of the device, and when used in airplanes or cars, they also save the amount of fuel consumed, so it can be said that such products and equipment are more user-friendly and environmentally friendly. (Khosravani, M. R & Reinicke, T., 2021) There are many types of structures with different configurations, different types of basic cells, different distribution of pores or their topology, so it is very important for the designer to know and decide which type of structure is most advantageous to use in the proposed product that will be subjected to a specific load. (Mishra, A., et al., 2023; Boursier Niutta, C. et al, 2023) The properties of cellular lightweight bodies are the result of a combination of their design and characteristics of the material used for their production. These two factors, together with the volume fraction V f of the cell bodies that is given by equation (1): (Monkova, K. et al., 2023) V f = (material volume)/(total sample volume) (1) are the determining parameters for their physical and mechanical properties. The aim of the presented research was to investigate the effect of volume fraction on the stiffness of the 3D printed Neovious structure in compression and to analyse the fracture surface. 2. Materials and methods In this study, the compression behaviour until failure of the Neovius structures with a basic cell of 10 x 10 x 10 mm, total sizes of the samples 40 x 40 x 50 mm and four various volume fractions ( V f = 12; 18.7; 25.5 and 40 %) were studied during compression tests. Neovius belongs to the so-called Triply Periodic Minimal Surfaces (TPMS). A minimal surface can be defined as a surface on which, at each point, the two principal curvatures are equal in value but have opposite signs (i.e., there is a mean curvature of zero value at all points). TPMS structures can be mathematically modelled using level-set equations. (Abueidda, D.W. et al, 2020) For the Neovius structure, the equation approximately describing surface is as follows (Monkova, K.; et al., 2023) (2) As the material for specimen production, the aluminium alloy AlSi10Mg was chosen. Manufacturing was conducted using the EP-M250 3D printing machine (Shining 3D company). The chemical composition of the AlSi10Mg powder complies with the DIN EN 1706 (EN AC-43000) standard (Data sheet Aluminium AlSi10Mg, Table 1). Table 1. Chemical composition of AlSi10Mg alloy (Data sheet Aluminium AlSi10Mg) Element Al Mg Si Ni Sn Pb Cu Zn Ti Mn Fe wt. (%) bal. 0.2–0.45 9–11 <0.05 <0.05 <0.05 <0.05 <0.1 <0.15 <0.45 <0.55 This alloy is widely recognised for its combination of low weight and favourable mechanical properties, along with high thermal and electrical conductivity, particularly following heat treatment. It is used to manufacture prototypes, finished products or parts and production tools. The presence of silicon makes the alloy both harder and more resistant than pure aluminium. (Matušů, M., et al., 2024) Considering the natural formation of an oxide layer on the surface of the aluminium alloy, the material has a high resistance to corrosion, which can be further improved by chemical anodization. This makes it suitable for use in humid environments and applications involving contact with water. (Fernandes, R.F., et al., 2024; Papuga, J., et al., 2024). The geometry of a basic Neovius structure cell is illustrated in Fig. 1a. The virtual models were prepared in PTC Creo 9.0 software, while the fabricated samples are displayed in Fig. 1b. Compression tests were conducted using an Instron 8802 servo-hydraulic testing machine with a maximum load capacity of 250 kN, in accordance with the ASTM E9 international standard (ASTM E9:2019), at ambient temperature and cross head speed 1 mm/min. During all experiments, specimens were oriented such that the 50 mm dimension (considered as specimen height) remained parallel to the direction of the applied load (normal to the printing direction).