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Indexed by:期刊论文

Date of Publication:2014-10-01

Journal:MATERIALS RESEARCH INNOVATIONS

Included Journals:SCIE、EI

Volume:18

Issue:6

Page Number:412-417

ISSN No.:1432-8917

Key Words:Semisolid process; Cooling slope; Globularisation mechanism

Abstract:Cooling slope process is a simple method to produce feedstock materials for semisolid processing. When the melt is poured onto a cooling slope, a semisolid slurry with spheroidal microstructure can be obtained. In this work, the mechanism of alpha-Al globularisation during cooling slope process is investigated. It shows that the cooling slope process can be divided into two stages. The first stage occurs at the upper position of the slope plate and cooling of the melt domains at this area. At the second stage, the melt breaks dendrite arms while flowing on the plate, and globular solids are formed at lower position. The combined effects of heterogonous nucleation and dendrite fragmentation are the main mechanisms for globularisation of the alloy microstructure.