PSI - Issue 56

Kevin Moj et al. / Procedia Structural Integrity 56 (2024) 120–130 Author name / Structural Integrity Procedia 00 (2019) 000–000

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2.2. Effect of the unit cell number on the mechanical properties of the structures Finite element models of cellular structures were designed using nTopology software. and simulations were performed using commercial ANSYS software. To evaluate the effect of the number of cells on mechanical

Fig. 2. Numerical analysis of cellular structures - study of the effect of the number of cells on strength properties.

properties. different models were developed. beginning with a cell structure consisting of one cell and ending with a structure containing twelve cells in one direction in space. The purpose of this analysis was to determine the number of cells at which the cell structure exhibits a stable effective Young's modulus. In defining effective values. it is assumed that the material is homogeneous and constant. A cellular structure composed of a sufficient number of unit cells is treated as a homogeneous material. and voids in the form of pores are not taken into account in determining the cross-sectional area required for calculating effective stresses. Effective strains are estimated from equation (1). which takes into account the difference between the measured length after deformation and the initial measured length. Effective stresses. on the other hand. are calculated from equation (2). accounting for the applied force and the initial cross-sectional area of the specimen. ��� � � � � � (1) ��� � � � � (2) The simulation included a uniaxial compression test. In general. two analysis concepts can be used. The first is to apply boundary conditions directly to the model. while the second requires creating two rigid plates to simulate contact between the testing machine and the specimen. Due to the significantly increased calculation time. the first option was chosen. Figure 2 shows the method for conducting the analysis based on the Schwarz TMPS cell. The parameters of the material model used were determined from a uniaxial tensile test of the base material. A linear elastic model was used in the numerical analysis.