Casting of Al-25%Si Alloy Strip by a Vertical Type Twin Roll Caster

Abstract

This study was aimed at investigating of Casting of hypereutectic Al-Si alloy strip by a vertical type twin roll caster. Hypereutectic Al-Si alloy has some useful advantages i.e., low thermal expansion, better thermal conductivity and wear registrant. Recently, the plate of hypereutectic Al-Si alloy which thickness is thinner than 1mm, is demanded. The hypereutectic Al-Si is hard and brittle. Therefore, only the many times of hot rolling was useful process to make thin plate. In the present study, the roll casting of Al-25%Si strip was tried by a vertical type high speed twin roll caster from the point of energy saving. The twin roll size of the roll was φ300×W100. Roll-load was set low enough to prevent the sticking of the strip. The roll speed was operated at 20m/min and 40m/min. The solidification length was 100mm. The Al-25%Si strip, which thickness was about 1.7mm, was cast directly from the molten metal. The primary Si was not dispersed uniformly. The eutectic Si became fine and globular. The roll cast Al-25%Si was expected superior ductility.