Liquid-liquid phase separation and solidification behavior of Al55Bi36Cu9 monotectic alloy with different cooling rates

Abstract The cooling rate has a significant effect on the solidification behavior and microstructure of monotectic alloy. In this study, different cooling rate was designed through casting in the copper mold with different bore diameters. The effects of different cooling rate on the solidification behavior of Al 55 Bi 36 Cu 9 (at.%) immiscible alloy have been investigated. The liquid-liquid phase separation of Al 55 Bi 36 Cu 9 immiscible alloy melt was investigated by resistivity test. The solidification microstructure and phase analysis of Al 55 Bi 36 Cu 9 immiscible alloy were performed by the SEM and XRD, respectively. The results showed that the liquid-liquid phase separation occurred in the solidification of Al 55 Bi 36 Cu 9 monotectic melt from 917 °C to 653 °C. The monotectic temperature, liquid phase separation temperature and immiscibility zone of Al 55 Bi 36 Cu 9 monotectic alloy was lower than those of Al-Bi binary monotectic alloy. The solidification morphology of Al 55 Bi 36 Cu 9 monotectic alloy was very sensitive to the cooling rate. The Al/Bi core-shell structure formed when Al 55 Bi 36 Cu 9 melt was cast in the copper mold with a 8 mm bore diameter.