Microstructures in centrifugal casting of SiC_p/AlSi9Mg composites with different mould rotation speeds

Abstract

Two ingots were produced by centrifugal casting at mould rotational speeds of 600 rpm and 800 rpm using 20 vol% SiC_p/AlSi9Mg composite melt, respectively. The microstructure along the radial direction of cross-sectional sample of ingots was presented. SiC particles migrated towards the external circumference of the tube, and the distribution of SiC particles became uniform under centrifugal force. Voids in 20 vol% SiC_p/AlSi9Mg composite melt migrated towards the inner circumference of the tube. The quantitative analysis results indicated that not only SiC particles but also primary α phases segregated greatly in centrifugal casting resulting from the transportation behavior of constitutions with different densities in the SiC_p/AlSi9Mg composite melt. In addition, the eutectic Si was broken owing to the motion of SiC_p/AlSi9Mg composite melt during centrifugal casting.

Keywords

SiC_p/Al composites / centrifugal casting / mould rotational speed / microstructures

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