PSI - Issue 61

Lívia Mendonça Nogueira et al. / Procedia Structural Integrity 61 (2024) 122–129 L. M. Nogueira et al. / Structural Integrity Procedia 00 (2024) 000–000

127

6

Fig. 4. Synthetic binary images with 20% porosity and representative ellipses generated by the MIL method for each analyzed case.

not significantly influence microstructural quantification. In the case where pores are oriented in a specific direction (Case (c) and Case (d)), the influence on determining the ellipse is more significant, experiencing a more pronounced deviation from isotropic conditions. It can also be observed that the angle ( θ ) of the fitted ellipse approaches the condition of 50° orientation set for these patterns. To assess the impact of porosity on these analyses, all four cases were also analyzed with a higher fixed porosity f p = 0 . 4. Table 2 presents the outputs of the anisotropy analysis. From these results, it can be observed that Case (a) and Case (b) again approach the condition of isotropy with respectively 94.5% and 92.2% of similarity. Regarding Case (c), comparing both the aspect ratio and orientation, there was a maximum di ff erence of approximately 4% to the previous analysis. It is important to highlight that the algorithm used for implementing the MIL method is stochastic, as directions are taken randomly. Therefore, small variations are already expected, even when analyzing similar pat terns. Consequently, these results support the idea that the MIL method o ff ers information about the microstructure’s arrangement and orientation, remaining independent of porosity.

Table 2. Anisotropy analysis from BoneJ - f p = 0 . 4. R

a

b

θ (°)

Case (a) Case (b) Case (c) Case (d)

0.945 0.922 0.745 0.468

39.37 34.03 35.01 52.16

41.67 31.39 26.08 24.40

61.59

2.03

45.98 42.05