Fig. 6.

Analysis of the coalescence of bubbles by tomoscopy at 208 tps (AlSi8Mg4 alloy). a 3D rendering of structure highlighting the bubbles under investigation. b Corresponding perpendicular slices of the structure. c Definition of five colour-coded planes through the four bubbles in a. d, e Images/slices obtained by the incremental reconstruction technique described in Supplementary Fig. 2. Numbers #nnn refer to time increments of 25 µs starting from an arbitrary point. d 3D rendering at various times showing the original configuration of numbered bubbles (#001). The configuration changes after 2.08 ms in #084 where bubble 2 and 3 have merged to a dumbbell-shaped intermediary bubble. In #137, (3.83 ms from the beginning) bubble 1 has completely merged into the dumbbell-shaped one. Even later, after 5.6 ms (#300) bubble 4 has also joined. e Slices in the planes defined in c showing the merger of bubbles in d in more detail