Centrifugal casting of leaded aluminium alloys

Abstract

Hollow cylindrical castings (90 mm outside diameter, 80 mm internal diameter and 150 mm length) of leaded aluminium alloys (AI-4.1Cu-15,20,25Pb) were prepared by verticle centrifugal casting technique. Operational parameters such as mould speed and pouring temperature were optimised for 20 wt-% lead alloys. These casting parameters (mould rotation speed 1600 rev min-1 and pouring temperature 900°C) were found to be suitable for 15-25 wt-%Pb alloys. Lead distribution in various sections of the casting was assessed by chemical analysis and metallographical study. Mechanical properties of cast alloys were assessed at room temperature. Lead is dispersed in AI-4.1Cu alloy matrix as globules and patches, and occurs in the interdendritic region of aluminium rich dendrites. Concentration of lead is more outside layers of casting than that inside the layers. Lead decreased mechanical properties of Al-4.1Cu alloy. © 2006 W. S. Maney & Son Ltd.