Hostname: page-component-745bb68f8f-lrblm Total loading time: 0 Render date: 2025-01-12T07:44:37.176Z Has data issue: false hasContentIssue false
  • English
  • Français

Modification of Fracture Energy of Niobium/sapphire Interface By Impurity Doping

Published online by Cambridge University Press:  10 February 2011

Hong Ji ,
Gary S. Was ,
J. Wayne Jones  and
Neville R. Moody
Hong Ji
Affiliation:
Physics Department, all at the University of Michigan, Ann Arbor, MI 48109 Department of Materials Science & Engineering, all at the University of Michigan, Ann Arbor, MI 48109
Gary S. Was
Affiliation:
Department of Materials Science & Engineering, all at the University of Michigan, Ann Arbor, MI 48109 Department of Nuclear Engineering & Radiological Sciences, all at the University of Michigan, Ann Arbor, MI 48109
J. Wayne Jones
Affiliation:
Department of Materials Science & Engineering, all at the University of Michigan, Ann Arbor, MI 48109
Neville R. Moody
Affiliation:
Sandia National Laboratories, Livermore, CA 94551–0969
Get access

Abstract

The effect of interface composition on the fracture energy and fracture toughness of the niobium/sapphire system was studied. Niobium films with thickness of 100 nm were deposited on (0001) sapphire substrates by physical vapor deposition (PVD). The interface was doped with silver to reduce the interfacial cohesion. The amount of silver ranged from less than 2.1 monolayers to 6.4 monolayers as measured by Rutherford backscattering spectrometer (RBS). The microscratch test was used in determining the interfacial fracture energy and the interfacial fracture toughness. Both interfacial fracture energy Gc and fracture toughness Kc decrease non-linearly with the amount of silver, and level off for samples with larger silver thickness ( > 4.2 monolayers). The values of interfacial fracture energy range from 3.43 J/m2 - 9.20 J/m2 for the sample doped with 2.1 monolayer silver (sample B) to 0.05 J/m2 - 0.5 J/m2 for samples with silver levels above 4.2 monolayers (samples D and E). The corresponding fracture toughnesses are 0.80 MPa-m½ - 1.29 MPa-m½ for sample B and 0.09 MPa-m½ - 0.30 MPa-m½ for samples D and E.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 458: Symposium W – Interfacial Engineering for Optimized Properties , 1996 , 191
Copyright
Copyright © Materials Research Society 1997

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. Reimanis, I. E., Dalgleigh, B. J., Brahy, M., Rühle, M., and Evans, A. G., Acta Metall. Mater., 38, 2645, (1990).Google Scholar
2. Elssner, G., Suga, T., and Turwitt, M., J. Phys. (Orsay), 46–C4, 597, (1985).Google Scholar
3. Jokl, M. L., Vitek, V., and McMahon, C. J., Acta Metallurgica, Vol. 28, 1479, (1980).Google Scholar
4. Elssner, G., Korn, D., and Rühle, M., Scripta Metallurgica et Materialia, Vol. 31, No. 8, 1037, (1994).Google Scholar
5. Ji, H., Was, G. S., Jones, J. W., and Moody, N. R., submitted to J. Appl. Phys.Google Scholar
6. Venkataraman, S., Kohlstedt, D. L., and Gerberich, W. W., J. Mater. Res., Vol. 7, No. 5, 1126 (1992).Google Scholar
7. Seah, M. P., Acta Metall., 28, 955, (1980).Google Scholar
8. Rice, J. R., Suo, Z., and Wang, J. S., in ‘Metal-Ceramic Interfaces’, (ed. Rühle, M., Ashby, M. F., Evans, A. G., and Hirth, J. P.), Pergamon Press, Oxford, (1989).Google Scholar
9. Korn, D., Elssner, G., Fischmeister, H. F., and Rühle, M., Acta Metall. Mater., Vol. 40, Suppl., s355, (1992).Google Scholar