Structure and Nanomechanical Properties of the Al-Si-Fe Alloy Produced by Blowing the Melt with Oxygen

The microstructure and nanomechanical properties of the Al-7% Si-1% Fe as-cast alloy produced by blowing oxygen into the melt have been studied. Blowing oxygen into liquid aluminum alloy results in the formation of Al2O3 nanoparticles, which increase the strength of the alloy after subsequent cooling and crystallization. Scanning electron and atomic force microscopy (EDS and EBSD analyses) have been used to examine the microstructure of the Al-7% Si-1% Fe alloy. The nanohardness and Young's modulus of alpha-Al in microvolumes are measured using nanoindentation. Blowing oxygen into the melt has been found to significantly decrease the random scatter of Young's modulus of alpha-Al. The results have been considered through the lens of modern knowledge of how composite materials of the aluminum matrix are strengthened.