Thermal stability of nanostructured Al93Fe3Cr2Ti2 alloys prepared via mechanical alloying Original Research Article

Thermal stability of nanostructured Al93Fe3Ti2Cr2 alloys prepared via mechanical alloying (MA) starting from elemental powders was investigated using a variety of analytical techniques including modulated differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, transmission electron microscopy coupled with energy dispersive spectrometry and microdiffraction. The results showed that the MA-processed Al93Fe3Ti2Cr2 alloy in the as-milled condition was composed of an Al-based supersaturated solid solution with high internal strains. Release of internal strains, intermetallic precipitation and grain growth occurred upon heating of the MA-processed Al alloy. Nevertheless, grain growth in the MA-processed Al alloy was very limited and fcc-Al grains with sizes in the range of 20 nm were still present in the alloys after exposure to 450 °C (0.77 Tm).