Hostname: page-component-848d4c4894-ndmmz Total loading time: 0 Render date: 2024-05-12T08:30:46.770Z Has data issue: false hasContentIssue false

Using the Rule of Mixtures to Examine the Hardness of Cu/Cu-Zr Multilayers

Published online by Cambridge University Press:  15 February 2011

T.P. Weihs
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
T.W. Barbee Jr.
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
M.A. Wall
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
Get access

Abstract

Cu/Cu-Zr multilayer foils were fabricated and indented to determine the degree to which multilayer hardness is enhanced by increasing the volume fraction of the harder phase. Using sputter deposition and thermal processing a series of foils was fabricated in which the thicknesses of the Cu layers remained fixed while the thicknesses of the alternate Cu-Zr layers varied. These samples were then indented both parallel and normal to their layering. In general, hardness increased as the volume fraction of the harder Cu-Zr phase rose. When the films were loaded parallel to their layering, the measured hardnesses were higher and the dependencies on volume fraction of the Cu-Zr phase were stronger than when the films were loaded normal to their layering. These results agree with predictions based on isostress and isostrain theories. The relationships between hardness and volume fraction are used to compare the hardnesses of the Cu-Zr phases: amorphous Cu-Zr, Cu51Zr14 and Cu9Zr2, and to show that the hardness of the textured, as-deposited Zr layers is highly anisotropic .

Type
Research Article
Copyright
Copyright © Materials Research Society 1993

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

REFERENCES

1 Foecke, T. and Lashmore, D.S., Scripta Met., 27, 651 (1992).CrossRefGoogle Scholar
2 Shih, K.K. and Dove, D.B., Appl. Phys. Let., 61, 654 (1992).CrossRefGoogle Scholar
3 Mirkarimi, P.B., Hultman, L. and Barnett, S.A., Appl. Phys. Let., 57, 2654 (1990).CrossRefGoogle Scholar
4 Cammarata, R.C., Schlesinger, T.E., Kim, C., Qadri, S.B. and Edelstein, A.S., Appl. Phys. Lett., 56, 1862 (1990).CrossRefGoogle Scholar
5 Bamett, C. R., Nix, W.D. and Tetelman, A.S., The Principles of Engineering Materials, pp. 318–20, Prentice-Hall, Inc., NJ (1973).Google Scholar
6 Tabor, D., The Hardness of Metals. Oxford (1951).Google Scholar
7 Hall, E.O., Proc Phys. Soc, Lond., B64, 747 (1951); N.J. Petch, J. Iron & Steel, 174, 25 (1953).CrossRefGoogle Scholar
8 Koehler, J.S., Phys. Rev. B, 2, 547 (1970) and S.L. Lehoczky, Phys. Rev. Lett., 41, 1814 (1978).CrossRefGoogle Scholar
9 Dieter, G.E., Mechanical Metallurgy, p. 37, McGraw-Hill, N.Y. (1976).Google Scholar
10 Glimois, J.L, Forey, P. and Feron, J.L., J. Less-Common Met., 113, 213 (1985).CrossRefGoogle Scholar
11 Johnson, W.L, Mater. Sci. Eng., 97, 1 (1988).CrossRefGoogle Scholar
12 Barbee, T.W. Jr., Walmsley, R.G., Marshall, A.F., Keith, D.L., and Stevenson, D.A., Appl. Phys. Lett., 38, 132 (1981).CrossRefGoogle Scholar
13 Kneller, E., Khan, Y., and Gorres, U., Z. Metallkd., 77, 43 (1986).Google Scholar
14 Weihs, T.P., Barbee, T.W. Jr., and Wall, M.A., Proceedings of Symposium O, "Phase Transformations in Thin Films," MRS Meeting, Spring 1993.Google Scholar
15 O'Neill, H., Hardness Measurements of Metals and Alloys, pp. 7778, Chapman and Hall, LTD, UK (1967).Google Scholar
16 Moral, F. R., J. Metals, 10, 662 (1958).Google Scholar
17 Lawley, A. and Maddin, R., Acta Met., 8, 275 (1960).CrossRefGoogle Scholar