Solid-liquid mixed casting of Al-Si alloy

Abstract

The paper presents a novel material preparation technology—Solid-liquid mixed casting technology. In the technology, large amounts of homogeneous alloy powder or heterogenous powder with perfect wettability are added into the superheated melt. After strong agitation, the mixed melt can be cast or hot processed. Applying solid-liquid mixed casting, three kinds of Al-Si alloys were investigated. The results show that, when the mass of powder accession to alloy melt is about 1, the mean size of primary Si in hyper-eutectic alloy can be controlled at less than 5 µm; and the mean grain size of α phase in hypo-eutectic alloy is less than 10 µm. This technology has the advantage of preparing material with very fine microstructure by fairly simple casting process, and may be a new practicable and valuable metal preparation technology.

Keywords

solid-liquid mixed casting / powder / melt

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