The Influence of Oxide-Salt Ratio on Crystallization of Lu₂Ti₂O₇ Phase from Molten Salt

Abstract:

Lu2Ti2O7 powders have been prepared using TiO2 and Lu2O3 oxides as precursors based on molten salt technique and the effects of salt-oxide ratio on the phase transformation is studied. A significant influence of salt-oxide ratio on phase transformation has been observed and the salt-oxide molar ratio of 3:1 is preferred for improved synthesis reaction efficiency. Such an experimental trend is analyzed with the assistant of JMA equation and the possible correlations between salt amount and the nucleation rate is given. After confirming linearly increasing of the crystal size with time, which is an indicative of interface controlled crystal growth kinetics, the investigations on the curves resulting from the logarithm of phase transformation fraction (ln[-ln(1-α)]) plots versus both the annealing time (lnt) and calcinations temperatures ( ) under isothermal and non-isothermal conditions respectively suggest that the enhanced crystallization is derived from the modification of salt amount to the nucleation rate.

• Periodical: Applied Mechanics and Materials (Volumes 275-277)
• Pages: 2321-2324
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.275-277.2321
• Online since: January 2013
• Authors: Shu Yu Zhang, Bao Rang Li, Run Hao Liu
• Keywords: JMA Equation, Molten Salt Method, Phase Transformation, Salt-Oxide Ratio

References

[1] Z.W. Song, J.F. Ma and H.Y. Sun, Ceram. Int. 35, 2675(2009).

[2] B. R. Li, H.B. Chang, D.Y. Liu and X.N. Yuan, Mater. Chem. Phys. 130, 755 (2011).

[3] C.C. Zhou, F.M. Liu, D. Peng, L.G. Cai and W.W. Zhong, J. Alloy. Compd. 505, 573 (2010).

[4] F. Bortolani and R. A. Dorey, J. Eur. Ceram. Soc. 30, 2073(2010).

[5] Z.Y. CAI, X.R. XING and L. LI, J. Alloy. Compd., 454, 466(2008).

[6] K. YOON, Y. CHO and D. KANG, J. Mater. Sci. 33, 2977 (1998).

[7] J. Mlek, D. vadla´k and T. Mitsuhashi, J. Non-Cryst. Solids, 352, 2243(2006).