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Thermal Evolution of Single Phase Lanthanum Zirconate

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Abstract:

Lanthania (La2O3) and zirconia (ZrO2) powders in ethanol based suspension were mechanochemically treated in a planetary ball mill for 12 hours at 200 rpm, dried and sintered at various temperatures from 400 to 1500 . Particles in nanometer sizes are produced after milling. X-ray diffractometry results show the formation of single phase lanthanum zirconate on subsequent heat treatment for 1h at 1500 . Phase evolution based on the intensities of the XRD plots and BET surface area analysis indicates three stages of crystallization: below 800 , between 800 and ~1100 , and above 1100 where reflections of La2Zr2O7 with pyrochlore structure are increased with further heating. Only endothermic energy peaks are observed in the differential thermal analysis (DTA) curve of the milled powders, which could be attributed to the reactions involving dehydroxylation, decarboxylation and complete disintegration of ethanol. This indicates that probably, lanthanum zirconate has grown on sintering at high temperatures from the very fine particles produced by mechanochemical activation during milling. Thermogravimetric analysis has recorded a total weight loss of ~9% from the original weight of the milled powder on sintering at 1500 . The values of the surface area of the powders are found to decrease while the crystallite size of La2Zr2O7 are increased with increasing temperature.

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Periodical:

Key Engineering Materials (Volumes 317-318)

Pages:

31-36

DOI:

https://doi.org/10.4028/www.scientific.net/KEM.317-318.31

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Online since:

August 2006

Authors:

Maria Ophelia D. Jarligo, Y.S. Kang, Akira Kawasaki

Keywords:

Crystallization, Lanthanum Zirconate, Mechanochemical Activation, Sintering

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© 2006 Trans Tech Publications Ltd. All Rights Reserved

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References

[1] S. Yamazaki, T. Yamashita, T. Matsui and T. Nagasaki: J. Nucl. Mater. Vol. 294 (2001), p.183.

Google Scholar

[2] X.Q. Cao, R. Vassen and D. Stoever: J. European Ceram. Soc. Vol. 24 (2004), p.1.

Google Scholar

[3] L. Minervini, R.W. Grimes and K.E. Sickafus: J. Am. Ceram. Soc. Vol. 83 (2000), p.1873.

Google Scholar

[4] M. A. Subramanian, G. Aravamudan and G.V. Subba Rao: Oxide pyrochlores-a review. Prog. Solid State Chem. Vol. 15 (1983), p.55.

DOI: 10.1016/0079-6786(83)90001-8

Google Scholar

[5] R. Vassen, X. Cao, F. Tietz, D. Basu and D. Stoever: J. Am. Ceram. Soc. Vol. 83 (2000), p. (2023).

Google Scholar

[6] X.Q. Cao, R. Vassen, W. Junger, F. Tietz, S. Schwartz and D. Stoever: J. Am. Cer. Soc. Vol. 84 (2001).

Google Scholar

[7] B. Saruhan, P. Francois, K. Fritscher and U. Schulz: Surf. Coat. Technol. Vol. 182 (2004), p.175.

Google Scholar

[8] A.R. Boccaccini, E. Bernardo, L. Blain and D.N. Boccaccini: J. Nucl. Mater. Vol. 327 (2004), p.148.

Google Scholar

[9] A.A. Digeos, J.A. Valdez, K.E. Sickafus, S. Atiq, R.W. Grimes and A.R. Boccaccini: J. Mater. Sci. Vol. 38 (2003), p.1597.

Google Scholar

[10] H. Lehmann, D. Pitzer, G. Pracht, R. Vassen and D. Stoever: J. Am. Ceram. Soc. Vol. 86 (2003), p.1338.

Google Scholar

[11] J. Nair, P. Nair, E.B.M. Doesburg, J.G. Van Ommen, J.R.H. Ross, A.J. Burggraaf and F. Mizukami: J. Mater. Sci. Vol. 33 (1998), p.4517.

DOI: 10.1023/a:1004496100596

Google Scholar

[12] S. Lutique, P. Javorsk, R.J.M. Konings, J.C. Krupa, A.C.G. van Genderen, J.C. van Miltenburg, F. Wastin: J. Chem. Thermodynamics Vol. 36 (2004), p.609.

DOI: 10.1016/j.jct.2004.03.017

Google Scholar

[13] K. Koteswara Rao, T. Banu, M. Vithal, G.Y.S.K. Swamy and K. Ravi Kumar: Materials Letters Vol. 54 (2002), p.205.

DOI: 10.1016/s0167-577x(01)00564-x

Google Scholar

[14] S. Sathyamurthy, M. Paranthaman, H-Y. Zhai, H.M. Christen, P.M. Martin, and A. Goyal: Rapid Communications, J. Mater. Res. Vol. 17 (2002), p.2181.

Google Scholar

[15] Y. Matsumura, M. Yoshinaka, K. Hirota and O. Yamaguchi: Solid State Communications Vol. 104 (1997), p.341.

Google Scholar

[16] M.O.D. Jarligo, Y-S. Kang, A. Kawasaki and R. Watanabe: Mat. Trans. Vol. 45 (2004), p.2634.

Google Scholar

[17] J. Nair, P. Nair, G.B.M. Doesburg, J.G. Van Ommen, J.R.H. Ross, A.J. Burggraaf and F. Mizukami: J. Am. Ceram. Soc. Vol. 82 (1999), p. (2066).

DOI: 10.1023/a:1009653604649

Google Scholar

[18] File No. 71-2363, Joint Committee for Powder Diffraction Systems-International Centre for Diffraction Data, (1998).

Google Scholar