Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-10T09:43:12.505Z Has data issue: false hasContentIssue false

Mechanism Of Thermally Assisted Creep Crack Growth

Published online by Cambridge University Press:  15 February 2011

Leonardo Golubović
Affiliation:
Department of Physics, West Virginia University, Morgantown, WV 26506
Dorel Moldovan
Affiliation:
Department of Physics, West Virginia University, Morgantown, WV 26506
Get access

Abstract

We use atomistic Monte-Carlo simulations to investigate the dynamics of cracks which sizes are smaller than the Griffith length. We demonstrate that such cracks can irreversibly grow proviso their size is larger than a certain critical length which is smaller than the Griffith length, as recently suggested [ L. Golubović and A. Peredera, Phys. Rev. E51, 2799 (1995)]. We show here that this thermally assisted creep crack growth is dominated by irreversible changes in the region of the crack tip, primarily in the form of dislocation emissions and nucleation of microcavities and voids. These processes act together during the crack growth: the crack tip region acts as a source for emissions of dislocations which subsequently serve as seeds for creation of vacancy clusters in a region away but still close to the crack tip. Eventually, passages between these vacancy clusters and the mother crack are formed and the crack thus increases in size. As this process repeats, the crack grows.

Type
Research Article
Copyright
Copyright © Materials Research Society 1996

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. Nishioka, K. and Lee, J. K., Philos. Mag. A 44, 779 (1981).Google Scholar
2. Selinger, R. L. B., Wang, Z.-G., Gelbart, W. M., and Ben-Shaul, A., Phys. Rev. A 43, 4396 (1991)Google Scholar
3. Wang, Z.-G., Landman, U., Selinger, R. L. Blumberg, and Gelbart, W. M., Phys. Rev. B 44, 378 (1991).Google Scholar
4. Selinger, R. L. B., Wang, Z.-G., and Gelbart, W. M., J. Chem. Phys. 95, 9128 (1991).Google Scholar
5. Golubović, L. and Feng, S., Phys. Rev. A 43, 5223 (1991).Google Scholar
6. Golubović, L. and Peredera, A., Phys. Rev. E 51, 2799 (1995).Google Scholar
7. Brenner, S. S., in Fiber Composite Materials ( American Society for Metals, Metals Park, OH, 1965), p. 11.Google Scholar
8. Lifshits, E. M. and Pitaevski, L. P., Physical Kinetics (Pergamon, Oxford, 1981), p. 427431.Google Scholar
9. Griffith, A. A., Philos. Trans. R. Soc. London Ser. A 227, 163 (1920); see also, L. D. Landau and E. M. Lifshits, Theory of Elasticity, 2nd ed. (Pergamon, Oxford, 1970), pp. 144–149.Google Scholar
10. Mott, N. F., Engineering 165, 16 (1948).Google Scholar
11. Herring, C., J. Appl. Phys. 21, 301 (1950).Google Scholar
12. Herring, C., J. Appl. Phys. 21, 437 (1950); F. R. N. Nabarro, Report of a Conference on the Strength of Solids ( Phys. Soc., London, 1948), p. 75.Google Scholar