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http://dx.doi.org/10.6111/JKCGCT.2017.27.5.229

Fabrication of TiAl alloy by centrifugal casting and its microstructure  

Ryu, Jeong Ho (Department of Materials Science and Engineering, Korea National University of Transportation)
Lee, Ho Jun (Department of Materials Science and Engineering, Korea National University of Transportation)
Cho, Hyun Su (Department of Materials Science and Engineering, Korea National University of Transportation)
Paeng, Jong Min (Department of Materials Science and Engineering, Korea National University of Transportation)
Park, Jong Bum (Department of Materials Science and Engineering, Korea National University of Transportation)
Lee, Jung-Il (Department of Materials Science and Engineering, Korea National University of Transportation)
Publication Information
Journal of the Korean Crystal Growth and Crystal Technology / v.27, no.5, 2017 , pp. 229-234 More about this Journal
Abstract
In this study, TiAl alloy was fabricated by a centrifugal casting method for turbo charge of automotive. Optimum conditions for defectless morphology using various ceramic mold were investigated. The crystal structure, microstructure, and chemical composition of the TiAl prepared by centrifugal casting were studied by X-ray diffractometer (XRD), optical microscopy (OM), field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS), microvickers hardness analyzer (HV). Two kinds of dendrite structures were observed with 4-fold and 6-fold symmetries. The FE-SEM, EDS and HV examinations of the as-cast TiAl showed that the thickness of the oxide layer (${\alpha}$-case) was typically less than $50{\mu}m$.
Keywords
TiAl; Centrifugal casting; Turbocharger; ${\alpha}$-Case; Dendrite;
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