Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
권호 표지

Evaluation of Metal-mold Reactions and Fluidity of TiAl Alloys

TiAl 합금의 주형계면반응 및 유동성 평가

  • 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)
  • Published : 2006.04.20
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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

References

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