Abstract
An Al-13Si-10Fe (wt.%) alloy was prepared via melt centrifugal atomization and compaction at a pressure of 6 GPa. The compact was porosity-free with good contacts between particles. The structure was very fine and consisted of primary α(Al) dendrites, eutectic silicon and needles of the β-Al₅FeSi phase. The Vickers hardness and compressive strength were 185 HV and 720 MPa, respectively. Surprisingly, the as-compacted alloy exhibited a certain degree of plasticity due to the refined morphology of needles. The alloy was annealed at 300-500 °C for 100 hours, and both the growth of Si particles and fragmentation of β-Al₅FeSi particles were observed. Structural transformations resulted in both a slow reduction of hardness and strength and a significant increase of plasticity. When the thermal stability of the Al-13Si-10Fe alloy was compared to that of the casting Al-12Si-1Cu-1Mg-1Ni alloy commonly utilized in the automotive industry for pistons for combustion engines, it was found to be superior.

Key words
aluminium, Al-Si-Fe alloy, rapid solidification, structure, mechanical properties

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