Issue 37

J. Kramberger et alii, Frattura ed Integrità Strutturale, 37 (2016) 153-159; DOI: 10.3221/IGF-ESIS.37.21 156 Figure 2 : (a) Computational model and (b) applied boundary conditions Stress (MPa) Plastic strain 400 0 800 24 Table 1 : Linearized stress-plastic behavior of the base material [15] The mechanical properties considered in the damage analysis for the studied porous structure have been obtained from the literature [15]. It should be noted that the values of material parameters c 1 and c 3 in Tab. 2 depend on the system of units in which the model is applied. c 1        2 2 2 cycle N mm c c c 2 c 3          2 4 4 cmm cycle(N mm ) c c c 4 100 24 2.7 ∙ 10 -5 1.27 Table 2 : Material parameters for damage initiation and evolution [15] R ESULTS AND DISCUSSION ig. 3 shows the state of all five models at different states through the analysis. After one cycle, there is no damage in any of the models, while after 20 cycles some cracks occur between large adjacent pores. F