Hostname: page-component-848d4c4894-xm8r8 Total loading time: 0 Render date: 2024-06-21T18:26:27.606Z Has data issue: false hasContentIssue false
  • English
  • Français

Dislocation-Based Deformation Mechanisms in Metallic Nanolaminates

Published online by Cambridge University Press:  29 November 2013

P.M. Anderson ,
T. Foecke  and
P.M. Hazzledine
Get access

Extract

The appeal of nanolayered materials from a mechanical viewpoint is that, in principle, plastic deformation can be confined to small volumes of material by Controlling both the frequency and magnitude of obstacles to dislocation motion. As we shall see, the spacing of obstacles can be used to impart large plastic anisotropy and work hardening. However, how strong can such materials be made as layer thickness (and therefore obstacle spacing) is decreased to the nanoscale level? In perspective, large, micron-scale, polycrystalline materials generally display improved yield strength (and fracture toughness) as grain size is decreased. This behavior at the micron scale can be explained via modeis that are built on two assumptions: (1) the strength of obstacles to crystal slip is sufficiently large to require pileups of numerous dislocations in order to slip past them; and (2) the strength of such obstacles does not change, even if their spacing is decreased. The modeling presented here shows that these assumptions may break down at the nanometer scale. The result is that there is a critical layer thickness in the nanometer range, below which improvement in strength does not occur.

Our discussion to follow briefly outlines a more macroscopic, micron-scale approach to determine yield strength, and then contrasts that with a sequence of events leading up to yield in nanolayered materials. We also address whether nanoscale materials are expected to exhibit more uniform or coarse slip than micron-scale materials. Finally, a semi-quantitative model of yield strength is developed which requires, as input, the strength of an interface to crystal slip transmission across it. We discuss several contributions to the interfacial strength and apply the theory to demonstrate a peak in strength for a 50 vol% Cu-50 vol% Ni multilayered sample.

Type
Mechanical Behavior of Nanostructured Materials
Information
MRS Bulletin , Volume 24 , Issue 2 , February 1999 , pp. 27 - 33
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.Leibfried, G., Z. Phys. 130 (1951) p. 214.CrossRefGoogle Scholar
2.Mitchell, T.E., Hecker, S.S., and Smialek, R.L., Phys. Status Solidi 11 (1965) p. 585.CrossRefGoogle Scholar
3.Li, J.C.M. and Liu, G.C.T., Philos. Mag. 15 (1967) p. 1059.CrossRefGoogle Scholar
4.Anderson, P.M. and Li, C., Nanostruc. Mater. 5 (1995) p. 349.CrossRefGoogle Scholar
5. For a discussion of the Orowan-like mechanism, see Embury, J.D. and Hirth, J.P., Acta Metall. Mater. 42 (6) (1994) p. 2051.CrossRefGoogle Scholar
6.Kreidler, E.R. Jr. and Anderson, P.M., in Layered Materials for Structural Applications, edited by Lewandowski, J.J., Ward, C.H., Jackson, M.R., and Hunt, W.H. Jr. (Mater. Res. Soc. Symp. Proc. 434, Pittsburgh, 1996) p. 159.Google Scholar
7.Kreidler, E.R. Jr., MS thesis, The Ohio State University, 1997.Google Scholar
8.Anderson, P.M. and Kreidler, E.R. Jr., in Thin Films: Stresses and Mechanical Properties VII, edited by Cammarata, R.C., Busso, E.P., Nastasi, M.A., and Oliver, W.C. (Mater. Res. Soc. Symp. Proc. 505, Warrendale, PA, 1998) p. 571.Google Scholar
9.Yamaguchi, M. and Umakoshi, Y., Prog. Mater. Sci. 34 (1990) p. 1.CrossRefGoogle Scholar
10.Porter, D.A., Easterling, K.E., and Smith, G.D.W., Acta Metall. 26 (1978) p. 1405.CrossRefGoogle Scholar
11.Shoykhet, B., Grinfeld, M.A., and Hazzledine, P.M., Acta Metall. 46 (1998) p. 3761.Google Scholar
12.Lu, Y-C., Kung, H., Griffin, A.J., Nastasi, M.A., and Mitchell, T.E., J. Mater. Res. 12 (1997) p. 1939.CrossRefGoogle Scholar
13.Matthews, J.W. and Blakeslee, A.E., J. Cryst. Growth 27 (1974) p. 118.Google Scholar
14.Nix, W.D., Metall. Trans. A 20 (1989) p. 2217.CrossRefGoogle Scholar
15.Frank, F.C. and van der Merwe, J., Proc. Roy. Soc. London, Ser. A 198 (1949) p. 216.Google Scholar
16.Kad, B.K., Hazzledine, P.M., and Fraser, H.L., in High-Temperature Ordered Intermetallic Alloys V, edited by Baker, I., Darolia, R., Whittenberger, J.D., and Yoo, M.H. (Mater. Res. Soc. Symp. Proc. 288, Pittsburgh, 1993) p. 495.Google Scholar
17.Rao, S.I., Hazzledine, P.M., and Dimiduk, D.M., in Grain-Size and Mechanical Properties—Fundamentals and Applications, edited by Otooni, M.A., Armstrong, R.W., Grant, N.J., and Ishizaki, K. (Mater. Res. Soc. Symp. Proc. 362, Pittsburgh, 1995) p. 67.Google Scholar
18.Koehler, J.S., Phys. Rev. B 2 (1970) p. 547.CrossRefGoogle Scholar
19.Rao, S.I., to be published (1998).Google Scholar
20.Louat, N.P., Acta. Metall. 33 (1985) p. 59.CrossRefGoogle Scholar
21.Forwood, C.T. and Clarebrough, L.M., Philos. Mag. A44 (1981) p. 31.CrossRefGoogle Scholar
22.Bonneville, J. and Escaig, B., Acta Metall. 27 (1979) p. 1477.CrossRefGoogle Scholar
23.Rao, S.I., Hazzledine, P.M., and Dimiduk, D.M., in Grain-Size and Mechanical Properties—Fundamentals and Applications, edited by Otooni, M.A., Armstrong, R.W., Grant, N.J., and Ishizaki, K. (Mater. Res. Soc. Symp. Proc. 362, Pittsburgh, 1995) p. 79.Google Scholar
24.Was, G.S. and Foecke, T., Thin Solid Films 286 (1996) p. 1.CrossRefGoogle Scholar
25.Oberle, R., PhD thesis, The Johns Hopkins University, 1993.Google Scholar
26.Foecke, T. and van Heerden, D., in Chemistry and Physics of Nanostructures and Related Non-Equilibrium Materials, edited by Ma, E., Fultz, B., Shull, R., Morral, J., and Nash, P. (The Minerals, Metals, and Materials Society, Warrendale, PA, 1997) p. 193.Google Scholar
27.Moffat, T.P., J. Electrochem. Soc. 142 (11) (1995) p. 3767.CrossRefGoogle Scholar
28.Hackney, S.A. and Milligan, W.W., Ultra-microscopy 37 (1991) p. 79.Google Scholar