Distribution of Al12Fe3Si and (FeAl6)Si in a HIPed Al-10.71 wt.% Si casting

An investigation on microstructural development in a hot isostatically pressed (HIPed) Al-10.71 wt.% Si casting is described. The as-cast material contained 0.006 total volume fraction of Al12Fe3Si and (FeAl6)Si particles but HIPing at 550 °C and 68.95MPa produced a moderate increase in this fraction, to a maximum value of 0.061 when HIPed for 120 min. Dislocations appeared to be the dominant nucleation sites for the particles in both the as-cast and the HIPed materials.