Cooling rate and microstructure of rapidly solidified Al–20 wt.% Si alloy

A 40 μm thick melt-spun ribbon was manufactured by using a single roller melt-spinning technique, and the temperature distribution of the melt-spun ribbon was obtained. The solidification time and the cooling rate of the melt-spun ribbon were estimated to be 6.59 × 10−5 s and 1.11 × 106 °C/s, respectively. The morphologies of primary silicon in the melt-spun ribbon were drastically changed to fine block-shape (maximum size of primary silicon is 5 μm, minimum size of primary silicon is 0.5 μm and average size of primary silicon is 2 μm), and the smaller eutectic silicon can be obtained due to the rapid solidification.