*3.2.1 FIB/SEM tomography of squeeze cast AlSi7Sr*

Examples show the AlSi7 alloy sample reinforced with Sr. and studied with the help of SEM at 5 keV. This method helps in production of about 250 scanning images, with the intersliced distance of 60 nm obtaining 15 μm of samples in

**Figure 2.**

*Image of a cell (Adopted from Wierzbicki et al. [47]). Sub image A shows the shadow of trench onto cell in XY-axis while sub image B shows its corrected version.*

milling direction. The Si in sample showed fibers and branches ~3–5 μm long with a diameter of 200–500 nm. These fibers are intermingled and represented by difference of colors. The interconnection junction sizes were 50–100 nm2 . The finally calculated volume fraction of Si in choral structure in reconstructed region was ~5%.
