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

A 40 mu m 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 x 10(-5) s and 1.11 X 10(6) degrees 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 mu m, minimum size of primary silicon is 0.5 mu m and average size of primary silicon is 2 mu m), and the smaller eutectic silicon can be obtained due to the rapid solidification. (c) 2005 Elsevier B.V. All rights reserved.