Interaction between Nb-Silicide Based Alloys and Y₂O₃ Crucible

Abstract:

Y₂O₃ crucibles have been prepared for as-cast Nb-22Ti-16Si-2Al-2Cr-2Hf and Nb-22Ti-16Si-2Al-2Cr alloys at 1950 °C. The microstructures, metal-crucible interfaces and contaminations were evaluated. Experimental results demonstrated that a mild interface reaction occurred between the Y₂O₃ crucibles and Hf, resulting in some inclusions dispersed in the metallic matrix. However, without Hf addition, no apparent reaction layers or inclusions were found. Both alloys were slightly contaminated with oxygen as the result of slow thermal dissociation of Y₂O₃, and its extent depended on Hf contents and holding times.

• Periodical: Materials Science Forum (Volume 816)
• Pages: 231-236
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.816.231
• Online since: April 2015
• Authors: Li Min Ma*, Jia Zhen Zhang, Guang Quan Yue, Hua Rui Zhang, Hu Zhang
• Keywords: Casting, Interaction, Nb-Silicide Based Alloy, Y₂O₃ Crucible

References

[1] J. Geng, P. Tsakiropoulos, G. Shao, A study of the effects of Hf and Sn additions on the microstructure of Nbss/Nb5Si3 based in situ composites, Intermetallics. 15(2007) 69-76.

DOI: 10.1016/j.intermet.2006.03.001

[2] W. Li, H. Yang, A. Shan, L. Zhang, J. Wu, Effect of Mo addition on the phase stability of β-Nb5Si3 phase, Intermetallics. 14(2006) 392-395.

DOI: 10.1016/j.intermet.2005.07.001

[3] B.P. Bewlay, M.R. Jackson, J.C. Zhao, P.R. Subramanian, A review of very-high-temperature Nb-silicide-based composites, Metall. Mater. Trans. A. 34 (2003) 2043-(2052).

DOI: 10.1007/s11661-003-0269-8

[4] B.P. Bewlay, M.R. Jackson, H.A. Lipsitt, The Balance of Mechanical and Environmental Properties of a Multielement Niobium-Niobium Silicide-based in situ Composite, Metall. Mater. Trans. A. 27(1996) 3801-3808.

DOI: 10.1007/bf02595629

[5] M.G. Mendiratta, D.M. Dimiduk, Strength and toughness of a Nb/Nb5Si3 composite, Metall. Mater. Trans. A. 24(1993) 501-504.

DOI: 10.1007/bf02657338

[6] X. Li, H. Chen, J. Sha, et al., The effects of melting technologies on the microstructures and properties of Nb-16Si-22Ti-2Al-2Hf-17Cr alloy, Mater. Sci. Engng. A. 23(2010) 6140-6152.

DOI: 10.1016/j.msea.2010.04.046

[7] A. Kostov, B. Friedrich, Predicting thermodynamic stability of crucible oxides in molten titanium and titanium alloys, Comp. Mater. Sci. 38(2006) 374-385.

DOI: 10.1016/j.commatsci.2006.03.006

[8] L.M. Ma, S.N. Yuan, R.J. Cui, et al. Interactions between Nb-silicide based alloy and yttria mould during directional solidification, Int. J. Refract. Met. Hard. Mater. 30(2012) 96-101.

DOI: 10.1016/j.ijrmhm.2011.07.009

[9] O. Fabrichnaya, C. Mercer, Phase relations in the HfO2-Y2O3-Al2O3 system, Comp. Coupling. Phase Diag. Thermo. Chem. 29(2005) 239-246.

DOI: 10.1016/j.calphad.2005.07.003

[10] L. Ma, X. Tang, B. Wang, et al. Purification in interaction between yttria mould and Nb-silicide based alloy during directional solidification: A novel effect of yttrium, Scripta Materialia. 3(2012) 233-236.

DOI: 10.1016/j.scriptamat.2012.04.025

[11] I. Barin, Thermochemical data of pure substances, 3rd ed., Wiley-VCH, Weinheim, (1997).

[12] R. Dicks, F. Wang, X. Wu, The manufacture of a niobium/niobium-silicide-based alloy using direct laser fabrication, J. Mater. Process Technol. 209(2009) 1752-1757.

DOI: 10.1016/j.jmatprotec.2008.04.042

[13] J.L. Murray, H.A. Wriedt, The O-Ti (Oxygen-Titanium) System, Bull. Alloy Phase Diag. 8(1987) 148-165.

[14] J. Zhu, A. Kamiya, T. Yamada, Surface tension, wettability and reactivity of molten titanium in Ti/yttria-stabilized zirconia system, Mater. Sci. Engng. 327(2002) 117-127.

DOI: 10.1016/s0921-5093(01)01732-4

[15] A.V. Kartavykh, V.V. Tcherdyntsev, J. Zollinger, TiAl-Nb melt interaction with AlN refractory crucibles, Mater. Chem. Phys. 116(2009) 300-304.

DOI: 10.1016/j.matchemphys.2009.03.032

[16] A.V. Kartavykh, V.V. Tcherdyntsev, J. Zollinger, TiAl-Nb melt interaction with pyrolytic boron nitride crucibles, Mater. Chem. Phys. 119(2010) 347-350.

DOI: 10.1016/j.matchemphys.2009.09.021