Cross-Sectional TEM Characterization of Re-Based Diffusion Barrier on Nb Substrate

Abstract:

Article Preview

Cross-sectional structures of a Re-based diffusion barrier coating on Nb as ultra high temperature material were investigated in order to verify the crystalline structure and composition of the coated layer. Three types coating specimens were prepared by electroplating Re from an aqueous solution on an Nb substrate, followed by Cr-pack cementation in vacuum. The coating process produced three distinct layers; an outer Cr(Re) layer, an intermediate Re-Cr-Nb layer, and an inner Nb(Re) layer. A crystal structure of Cr(Re) and Nb(Re) layers possess similar single crystal bcc structure. The Re-Cr-Nb layer expected to act as a diffusion barrier between the substrate and the outer reservoir layer was comprised of cubic c phase and hexagonal Laves C14 phase. Moreover, several crystal defects such as dislocations and stacking faults as well as voids and cracks are observed in the coating specimen.

Info:

Periodical:

Edited by:

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

Pages:

318-323

DOI:

10.4028/www.scientific.net/MSF.696.318

Citation:

S. Eni et al., "Cross-Sectional TEM Characterization of Re-Based Diffusion Barrier on Nb Substrate", Materials Science Forum, Vol. 696, pp. 318-323, 2011

Online since:

September 2011

Export:

Price:

$38.00

[1] K. Saito, S. Hayashi, T. Narita, I. Iwanaga and R. Tanaka: Mater. Sci. Forum 522-523 (2006) 309-316.

[2] M. Fukumoto, Y. Matsumura, S. Hayashi, K. Sakamoto, A. Kasama, R. Tanaka, and T. Narita: Oxidation of Metals 60 (2003) 335-346.

DOI: 10.1023/a:1026075420438

[3] R. C. Reed, in: The Superalloy, Fundamentals and Applications, Cambridge University Press (2006).

[4] T. Jin, W. Wang, X. Sun and Z. Hu: Mater. Sci. Forum 638-642 (2010) 2257-2262.

[5] M. J. Pomeroy: Mater. and Design 26 (2005) 223-231.

[6] L. A. Bendersky and F.W. Gayle: J. Res. Natl. Inst. Stand. Technol. 106 (2001) 997–1012.

[7] J.M. Joubert: Progress in Mater. Sci. 53 (2008) 528-583.

[8] J.M. Joubert and M. Phejar: Progress in Mater. Sci. 54 (2009) 945-980.

[9] D. J. Thoma, J.H. Perepezko, D.H. Plantz and R.B. Schwartz: Mat. Sci. Eng. A156 (1992) 97-108.

[10] T.B. Massalski: Binary Alloys Phase Diagram, 2nd ed. ASM International, (1990).

In order to see related information, you need to Login.