Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2025-01-02T21:44:54.511Z Has data issue: false hasContentIssue false
  • English
  • Français

Surface composites: A new class of engineered materials

Published online by Cambridge University Press:  31 January 2011

Rajiv Singh  and
James Fitz-Gerald
Rajiv Singh
Affiliation:
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611
James Fitz-Gerald
Affiliation:
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611
Get access

Abstract

To integrate irreconcilable material properties into a single component, a new class of engineered materials termed “surface composites” has been developed. In this engineered material, the second phase is spatially distributed in the near surface regions, such that the phase composition is linearly graded as a function of distance from the surface. Surface composites are different from existing engineered materials such as “bulk composites” and “functionally graded materials” (FGM). Unlike bulk composites, the surface phase in surface composites is present only at the near surface regions. In contrast to FGM, the graded properties of surface composites are achieved by unique morphological surface modification of the bulk phase. To fabricate surface composites, the initial surface of the bulk material is transformed using a novel multiple pulse irradiation technique into truncated cone-like structures. The laser induced micro-rough structures (LIMS) possess surface areas which are up to an order of magnitude higher than the original surface. The second phase is deposited on the surface using thin or thick film deposition methods. A key characteristic of surface composites is the formation of a three-dimensional, compositionally and thermally graded interface, which gives rise to improved adhesion of the surface phase. Examples of various types of surface composites such as W/Mo, silica/SiC, diamond/steel, etc. are presented in this paper. The unique properties of surface composites make them ideal engineered materials for applications involving adherent thick film coatings of thermally mismatched materials, compositional surface modification for controlled catalytic activity, and creating adherent metal-ceramic and ceramic-polymeric joints.

Type
Articles
Information
Journal of Materials Research , Volume 12 , Issue 3 , March 1997 , pp. 769 - 773
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. See, for example, Fundamentals of Discontinuously Reinforced MMC's, edited by Suresh, S., Mortensen, A., and Needleman, A. (Butterworth-Heinemann, Guildford, U.K., 1993).Google Scholar
2. “Metal Matrix Composites—Processing, Microstructure and Properties, 12 Risø International Symposium”, edited by Hansen, N.et al. (Roskilde, Denmark, Risø, 1991).Google Scholar
3.Holt, J. B., Kozumi, M., Hirai, T., and Munir, Z. A., Functionally Gradient Materials (Am. Ceram. Soc., Westerville, OH, 1992).Google Scholar
4.Williamson, R. L., Rabin, B. H., and Drake, J. T., J. Appl. Phys. 74, 1321 (1992).Google Scholar
5.Hirano, T., Teraki, J., and Yamada, T., in Proc. 1st Int. Symp. on FGM, edited by Yamanouchi, M., Koizumi, M., Hirai, T., and Shiota, I., Tokyo, Japan, 1995, p. 5.Google Scholar
6.Singh, R. K., Moudgil, B. M., Behl, S., and Bhattacharya, D., Patent, U.S., 5 473 138 (1995).Google Scholar
7.Singh, R. K., Gilbert, D. R., and Fitz-Gerald, J. (unpublished research).Google Scholar
8.Singh, R. K. and Narayan, J., Phys. Rev. B 43, 8843 (1990).CrossRefGoogle Scholar
9.Cheung, J. T. and Sankur, H., CRC Critical Rev. Solid State Mater. 15, 63 (1988).CrossRefGoogle Scholar
10.Singh, R. K. and Fitz-Gerald, J. F., Phys. Rev. Lett. (in press).Google Scholar