Figure 9
The horizontal axis is labeled “Porosity, V f” and ranges from 0 to 0.2 in increments of 0.05 units. The vertical axis is labeled “Normalized Plastic Flow Stress, lowercase sigma subscript f over lowercase sigma subscript 0” and ranges from 0 to 1.6 in increments of 0.2 units. Four series are shown in the legend: “Analytical solution”, “S C”, “B C C”, and “F C C”. All series start near 1.0 at zero porosity and decrease as porosity increases. At 0.05, values are around 0.9 to 0.93; at 0.1, around 0.82 to 0.87; at 0.15, around 0.75 to 0.8; and at 0.2, around 0.68 to 0.75. The analytical solution remains slightly higher than the numerical results across all porosity values, while the B C C results appear slightly lower than the others. Note: All numerical data values are approximated.Plastic flow stress, normalized by the yield strength of the solid material ( of 205 MPa), as a function of porosity for the three periodic closed-cell porous structures