Abstract
Experiments on the reaction between graphite and liquid Fe-Ti alloys were performed with a mirror furnace on board an airplane during parabolic flights. Small Fe-Ti alloy samples were melted in contact with graphite and held for some seconds at a temperature of 1550 °C. The samples were melted and solidified during a microgravity period. Carbon and titanium atoms reacted in the melt and titanium carbides were formed. In the experiments, a precipitation zone with faceted titanium carbide crystals dispersed in high carbon Fe-C-Ti alloy matrix was obtained near the graphite/alloy interface. The thicknesses of the carbide precipitation zones were measured and effects of alloy composition on the growth rates of the carbide zones were revealed by experiments and calculations. It was shown that the process was controlled by the diffusion of titanium in the liquid at low titanium concentrations and by diffusion of carbon through the precipitation layer at high titanium concentrations in the melt. Supersaturation of the carbide in front of the reaction interface was predicted from the calculations. The analysis showed that homogeneous nucleation of titanium carbide can readily occur in the alloys. Carbide morphologies were analyzed, and the mechanisms which lead to their formation are discussed.
Similar content being viewed by others
References
J.M. Panchal, T. Vela, and T. Robisch: Advances in Powder Metallurgy and Particulate Materials—1992, Metal Powder Industries Federation and American Powder Metallurgy Institute, Princeton, NJ, 1993, vol. 8, pp. 125–140.
J.M. Panchal and T. Vela: How Concept Becomes Reality, 36th International SAMPE Symposium and Exhibition, 1991, Society for the Advancement of the Material and Process Engineering, vol. 36.II, pp. 1973–87.
J.M. Panchal, T. Vela, and T. Robisch: Fabrication of Particulate Reinforced Metal Composites, ASM INTERNATIONAL, Materials Park, OH, 1990, pp. 245–60.
B.V. Chambers, T.Z. Kattamis, J.A. Cornie, and M.C. Flemings: Solidification Processing 1987, The Institute of Metals, London, 1988, pp. 465–68.
T.Z. Kattamis and T. Suganuma: Mater. Sci. Eng., 1990, vol. A128 (2), pp. 241–52.
B.S. Terry, and O.S. Chinyamakobvu: Mater. Sci. Technol., 1992, vol. 8, pp. 399–405.
B.S. Terry and O.S. Chinyamakobvu: J. Mater. Sci. Lett., 1991, vol. 10, pp. 628–29.
Å. Bergman, A. Jarfors, Z. Liu, and H. Fredriksson: Key Eng. Mater., 1993, vols. 79–80, pp. 213–34.
Z. Liu and H. Fredriksson: Metall. Mater. Trans. A, 1997, vol. 28A, pp. 471–483.
Z. Liu and H. Fredriksson: Microgravity Q., 1993, vol. 3, pp. 215–23.
Z. Liu and H. Fredriksson: Metall. Mater. Trans, 1996, vol. 27A, pp. 407–14.
C. Lockowandt, K. Löth, L. Ekbom, A. Eliasson, and A. Jarfors: Proc. VIIIth Eur. Symp. on Materials and Fluid Science in Microgravity, 1992, esa SP-333, vol. 1, pp. 383–86.
H. Ohtani, T. Tanaka, M. Hasebe, and T. Nishizawa: CALPAD, 1988, vol. 12, pp. 225–46.
J.C. Brice: The Growth of Crystals from Liquids, North-Holland, Amsterdam, 1977, p. 96.
F.J.J.V. Loo and G.F. Bastin: Metall. Trans. A, 1989, vol. 20A, pp. 403–11.
Y. Guo, C. Wang, and H. Yu: Metall. Trans. B, 1990, vol. 21B, pp. 537–41.
C.H.P. Lupis and J.F. Elliott: Trans. TMS-AIME, 1965, p. 233, pp. 257–58.
O. Kubaschevski and C.B. Alcock: Metallurgical Thermochemistry, 5th ed. Pergamon, Elmsford, NY, 1979.
K.G. Sigworth and J.F. Elliott: Metal science, 1974, vol. 8, pp. 298–310.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Liu, Z., Fredriksson, H. On the kinetics of carbide precipitation during reaction between graphite and Fe-Ti liquids under microgravity. Metall Mater Trans A 28, 707–719 (1997). https://doi.org/10.1007/s11661-997-0057-y
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11661-997-0057-y