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Evaluation of Metal-mold Reactions and Fluidity of TiAl Alloys  

Lee, Sang-Hwa (Department of Material Science and Engineering, Donga University)
Sung, Si-Young (Department of Advanced Materials Engineering, Sungkyunkwan University)
Choi, Bong-Jae (Department of Advanced Materials Engineering, Sungkyunkwan University)
Kim, Myoung-Gyun (New Metallic Materials Research Team, Research Institute of Industrial Science and Technology)
Kim, Young-Jig (Department of Advanced Materials Engineering, Sungkyunkwan University)
Publication Information
Journal of Korea Foundry Society / v.26, no.2, 2006 , pp. 98-103 More about this Journal
Abstract
Metal-mold reactions between investment mold and TiAl alloys were investigated for the economic net-shape forming of TiAl alloys. The effect of mold preheating temperatures on the metal-mold reaction were investigated using a vacuum induction-melting furnace. In the case of TiAl alloys, there were no ${\alpha}$-case formation reactions. There were neither interstitial nor substitutional ${\alpha}$-case formations as TiAl alloys have both negligible solubility of oxygen and low activity in molten states. The fluidity of TiAl alloys increases with mold preheating temperature since they have a peritectic reaction that appears in the form of envelope, surrounding each particles of the primary constituent. The results of the investment casting of TiAl alloys confirm that the casting route in our study can be an effective approach for the economic net-shape forming of TiAl alloys.
Keywords
Investments casting; Alpha-case; Net-shape forming; TiAl Alloys; Fluidity;
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1 T. Tetsui : Adv. Eng. Mater., 'Application of TiAI in a turbocharger for passenger vehicles', 3 (2001) 307-310   DOI   ScienceOn
2 S. Y. Sung, M. G. Kim and Y. J. Kim, J. Kor. Inst, Met.& Mater. 'A study of the identification of metal/mold reaction product of Ti investment casting', 41 (2003) 557-561
3 D. Eylon, M. M. Keller and P. E. Jones: Intermetallic, 'Development of permanent-mold cast TiAl automotive valves', 6 (1998) 703-708   DOI   ScienceOn
4 M. C. Flemings, 'Solidification processing', McGraw-Hill, New York, 1974
5 C. M. Austin : Solid State & Materials Science, 'Current status of gamma Ti aluminides for aerospace applications', 4 (1999) 239-242   DOI   ScienceOn
6 S. Y. Sung and Y. J. Kim, Mater. Sci. Eng. A, 'Alpha-Case Formation Mechanism on Titanium Investment Castings', 405 (2005) 173-177   DOI   ScienceOn
7 M. Maeda, T. Kiwake, K. Shibuya and T. Ikeda, Mater. Sci. Eng. A, 'Activity of aluminium in molten Ti-AI alloys', 239-240 (1997), 276-280
8 A. Lasalmonie : Intermetallics, 'Intermetallics: Why is it so difficult to introduce them in gas turbine engines?', xx (2006) 1-7
9 A. Choudhury and M. Blum, Vacuum, 'Economical production of titanium-aluminide automative valves using cold wall induction melting and centrifugal casting in a permanent mold', 47 (1996), 829-831   DOI   ScienceOn
10 J. Campbell, Cast Metals, 'Review of fluidity concepts in casting', 7 (1995) 227-237   DOI
11 Y. W. Kim: JOM, 'Ordered intermetallic alloys, part III: Gamma titanium aluminides', 48 (1994) 30-39
12 C. Leyens and M. Peters, 'Titanium and Titanium Alloys', Wiley-VCH, Weinheim, 2003