A Novel Method for Semi-Solid Casting of Hypereutectic Gray Cast Iron in Expendable Mold

Abstract:

In the present research, the possibility of single stage semi-solid casting of a hypereutectic gray cast iron in a sand mold was investigated. For this purpose, a specially designed chilled sprue sand mold rigged to a vertical centrifugal casting machine was used. The molten cast iron was poured in the chilled sprue sand mold at 1275 oC at a rotation speed of 400 rpm. Two control samples were also poured at 1275 oC under gravity and centrifugal casting conditions in the same mold without sprue chilling. Microstructures and mechanical properties of the specimens were then characterized. The results showed that the average length and thickness of the primary solid phase, i.e. the Kish graphite, and those of the eutectic flake graphite were smaller in semi-solid centrifuged castings and their hardness were higher than those of the control samples. The results are discussed in terms of the shearing and chilling effects of the designed sprue during the initial stages of pouring.

• Periodical: Solid State Phenomena (Volume 256)
• Pages: 237-242
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.256.237
• Online since: September 2016
• Authors: Safar Rostamzadeh, BEHZAD NIROUMAND*, Ali Maleki
• Keywords: Centrifugal Casting, Hypereutectic Gray Cast Iron, Sand Mold, Semisolid Casting

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