Hostname: page-component-8448b6f56d-cfpbc Total loading time: 0 Render date: 2024-04-19T09:28:25.706Z Has data issue: false hasContentIssue false
  • English
  • Français

The Oxidation of Ni and Ni-20Cr Deposited with Chromia Thin Films VIA Combustion CVD

Published online by Cambridge University Press:  10 February 2011

A. E. Alexiou ,
M. R. Hendrick  and
J. M. Hampikian
A. E. Alexiou
Affiliation:
School of Materials Science and Engineering Georgia Institute of Technology, Atlanta, GA 30332-0245 U.S.A.
M. R. Hendrick
Affiliation:
MicroCoating Technologies, Inc., 3901 Green Industrial Way, Chamblee, GA 30341, U.S.A
J. M. Hampikian
Affiliation:
Corresponding author
Get access

Abstract

Chromia thin films were deposited onto substrates of Ni and Ni-20Cr by gaseous fuel combustion chemical vapor deposition. The chemical precursor utilized to achieve chromia films was aqueous 0.27M chromium nitrate, and the depositions took place within the flame at temperatures between 200 and 550°C. Amorphous coatings were deposited between 200 and 375°C, whereas crystalline coatings of chromia (eskolaite) were deposited between 400 and 550°C. The eskolaite deposition rate was approximately five times faster than the amorphous chromia. Chromia coatings containing 2 wt% yttria were also formed. The deposition temperature necessary to form crystalline chromia/yttria coatings was slightly higher (∼50°C) than those containing chromia only. The ability of the various coatings to provide oxidation protection was characterized using thermogravimetric analysis (TGA). The eskolaite coatings that are at least 1 im thick reduce the oxidation mass gain/area of Ni-20Cr by nearly a factor of ten and the parabolic constant by an order of magnitude, whereas the amorphous chromia coatings that are 0.6 μm thick do not demonstrate such an improvement. Yttria-doped chromia coatings further reduce the parabolic constant by two orders of magnitude, consistent with expectation. Characterization of the coatings was accomplished using a variety of techniques, including SEM, TEM, EDS, and XRD.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 555: Symposium OO – Properties and Processing of Vapor-Deposited Coatings , 1998 , 67
Copyright
Copyright © Materials Research Society 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Hou, P.Y. and Stringer, J., Materials Science and Engineering, A202 (1995) 1.Google Scholar
2. Whittle, D.P. and Stringer, J., Phil. Trans. R. Soc. London, Ser. A, 27 (56) (1979) 309.Google Scholar
3. Hunt, A. T., Carter, W.B., and Cochran, J.K., Jr., Applied Physics Letters, 63 (2) (1993), 266.Google Scholar
4. Hunt, A.T., Cochran, J.K., and Carter, W.B., “Combustion Chemical Vapor Deposition of Films and Coatings,” U.S. Patent number 5,652,021, issued 7/29/97.Google Scholar
5. Hendrick, M.R., Hampikian, J.M., and Carter, W.B., Journal of the Electrochemical Society, 145 (8) (1998) 3986.Google Scholar
6. Valek, B.C. and Hampikian, J.M., Surface and Coatings Technology, 94–95 (1997) 13.Google Scholar
7. Carter, W.B., Book, G.W., Polley, T.A., Stollberg, D.W., and Hampikian, J.M., Thin Solid Films (in press).Google Scholar
8. Stollberg, D.W., Carter, W.B., and Hampikian, J.M., Surface and Coatings Technology, 94–95 (1997) 137.Google Scholar
9. Carter, W.B., Hampikian, J.M., Godfrey, S., and Polley, T.A., Materials and Manufacturing Processes, 10 (5) (1995) 1007.Google Scholar
10. Book, G.W., Carter, W.B., Polley, T.A., and Kozaczek, K.J., Thin Solid Films, 287 (1–2) (1996) 32.Google Scholar
11. Hwang, T.J., Hendrick, M.R., Shao, H., Hornis, H.G., and Hunt, A.T., Materials Science and Engineering, A244 (1998) 91.Google Scholar
12. Pieraggi, B., Oxidation of Metals, 27 (1987) 177.Google Scholar
13. Pfeil, L.B., U.K. Patent 574,088, 1947.Google Scholar
14. Hou, P.Y. and Stringer, J., Materials Science and Engineering, 87 (1987) 295.Google Scholar
15. Alexiou, A.E., Master's Thesis, Georgia Institute of Technology (1998).Google Scholar