Micro-structural development in Al–Si microcrystalline alloys

Structural changes in thermally treated microcrystalline Al–11 wt.%Si ribbon were studied by x-ray diffraction, differential scanning calorimetry, transmission electron microscopy and optical microscopy. Two successive types of microstructure development were found to appear in different temperature intervals: decomposition of supersaturated Al solid solution in range from 423 to 473 K, and structural coarsening of silicon particles between 723 and 800 K. The final microstructure of ribbon exhibits a nearly random distribution of silicon particles between 0.8 and 1.8 μm in diameter depending on time and temperature of annealing. [Copyright &y& Elsevier]