Evolution of Al2O3 Scale Formed on Ni-Al-Pt Alloy in Atmospheres Containing Water Vapor

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High temperature cyclic oxidation behavior of γ'-base Ni-25Al-10Pt (in at.%) alloy was investigated at 1000°C in air with and without 30vol.%H2O. The oxidation mass gain during the initial stage of oxidation was similar in both atmospheres, but the oxidation rate in air+H2O was lower in the longer steady-state oxidation stage. Metastable Al2O3, which formed during the initial stage of oxidation, transformed completely after about 100hr of oxidation in dry air. The transformation to α-Al2O3 also occurred in air+H2O, but complete transformation to α-Al2O3 was not observed during the oxidation time in the present study. θ-Al2O3 grains remained for longer on the α-Al2O3 layer in air+H2O and became significantly coarser with oxidation time. The present results indicate that water vapor delays the metastable to α-Al2O3 phase transformation, and decreases the growth rate of α-Al2O3.

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Edited by:

Toshio Maruyama, Masayuki Yoshiba, Kazuya Kurokawa, Yuuzou Kawahara and Nobuo Otsuka

Pages:

132-137

DOI:

10.4028/www.scientific.net/MSF.696.132

Citation:

M. Auchi et al., "Evolution of Al2O3 Scale Formed on Ni-Al-Pt Alloy in Atmospheres Containing Water Vapor", Materials Science Forum, Vol. 696, pp. 132-137, 2011

Online since:

September 2011

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$38.00

[1] H. Asteman, J. Svensson, M. Norell, L. Johansson, Oxidation of Metals 54, 11–26 (2000).

[2] R. Janakiraman, G. H. Meier, F. S. Pettit, Metallurgical and Materials Transactions A 30, 2905-2913 (1999).

[3] S. Hayashi and T. Narita, Oxidation of Metals 58, 319-330 (2002).

[4] H. Buscail, S. Heinze, Ph. Dufour, J. P. Larpin, Oxidation of Metals 47, 445-464 (1997).

[5] B. Gleeson, N. Mu, S. Hayashi, Journal of Materials Science 44, 1704-1710 (2009).

[6] M. W. Brumm and H. J. Grabke, Corrosion Science 33, 1677 (1992).

[7] D. J. Young, D. Naumenko, L. Niewolak, E. Wessel, L. Singheiser and W. J. Quadakkers, Materials and Corrosion 61, 838-844 (2010).

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