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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b)

a)

Fig. 1. (a) Neovius type of structure – a basic cell; (b) produced samples with four different volume fractions Vr .

3. Results and discussion The recorded dependences of force load on displacement for samples with all investigated volume fractions are shown in Fig. 2. The tests were stopped at the sample with volume fraction of 40 % due to the testing machine limit. The compressive strength, corresponding to Pmax (first local peak), is found increased with the volume fraction, however without following a linear/proportional rule, signifying that the strength augmentation rate exceeds the volume fraction ( V f ) increment (e.g. P max,2 / P max,1 > V f, 2 / V f, 1 ).

Fig. 2. Experimentally obtained force-displacement curves.

The data were processed, and the axial compression stiffness of individual samples was evaluated. Stiffness is a measure of a material's resistance to deformation under an applied load, and it is expressed as the force required to produce a unit elastic deformation coming from the formula k = F/y , where F represents the applied force and y refers to the resulting deformation. The results (Fig. 3) showed that the trend of axial compression stiffness is linearly increasing with the volume fraction that can be described by equation (1) with the coefficient of determination R 2 = 0.9986 %. = 3.3852 + 15.904. (3)

Fig. 3. Dependence of the compression stiffness of the Neovious structure on the volume fraction.