Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-25T17:42:22.800Z Has data issue: false hasContentIssue false
  • English
  • Français

An Atomistic Study of Hydrogen Effects on the Fracture of Tilt Boundaries in Nickel.

Published online by Cambridge University Press:  25 February 2011

N. R. Moody  and
S. M. Foiles
N. R. Moody
Affiliation:
Sandia National Laboratories, Livermore, CA 94551–0969.
S. M. Foiles
Affiliation:
Sandia National Laboratories, Livermore, CA 94551–0969.
Get access

Abstract

In this study, molecular dynamics simulations were used to fracture Σ9 tilt boundaries in nickel lattices containing a range of trap site hydrogen concentrations. These lattices were created in a previous study using Monte Carlo simulations and the Embedded Atom Method to duplicate room temperature exposure to a hydrogen environment. The molecular dynamics simulations were run at absolute zero to immobilize the hydrogen distributions for determination of trap site occupancy effects on grain boundary fracture. In all lattices, fracture began by the breaking of bonds next to polyhedral defect sites that characterize the boundary structure followed by rapid failure of the remaining bonds. The effect of hydrogen was to lower the stress for fracture from 18 GPa to a lower limiting value of 8 GPa as the trap sites along the boundary plane filled. The simulations showed that the atoms at these sites were the only atoms involved in the fracture process. Within the constraints imposed on these calculations, the results of this study showed that the ‘inherent’ effect of hydrogen in the absence of plastic deformation is to reduce the cohesive force between atoms across the boundary.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 238: Symposium Cb – Structure and Properties of Interfaces in Materials , 1991 , 381
Copyright
Copyright © Materials Research Society 1992

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. Moody, N. R., Robinson, S. L., and Perra, M. W., Hydrogen Effects on Material Behavior. edited by Moody, N. R. and Thompson, A. W. (TMS, Warrendale, PA, 1990) pp. 625–35.Google Scholar
2. Moody, N. R., Robinson, S. L., and Garrison, W. M., Res Mechanica 30, 143 (1990).Google Scholar
3. Moody, N. R., Perra, M. W., and Robinson, S. L., Scripta Metallurgica 22, 1261 (1988).Google Scholar
4. Perra, M. W., in Environmental Degradation of Engineering Materials in Hydrogen, edited by Louthan, M. R. Jr, McNitt, R. P., and Sisson, R. D. Jr (VPI Press, Blacksburg, VA, 1981) pp. 321–33.Google Scholar
5. Mutschele, T. and Kirchheim, R., Scripta Metall. 21, 135 (1987).Google Scholar
6. Fukushima, H. and Birnbaum, H. K., Acta Metall. 22, 851 (1984).Google Scholar
7. Hirth, J. P., Metall. Trans. A 11A, 861 (1980).Google Scholar
8. Daw, M. S., Baskes, M. I., Bisson, C. L., and Wolfer, W. G., in Modeling Environmental Effects on Crack Growth Processes, edited by Jones, R. H. and Gerberich, W. W., (TMS-AIME, Warrendale, PA 1986) pp.99–124.Google Scholar
9. Daw, M. S. and Baskes, M. I., Phys. Rev. Lett. 50, 1285 (1983).CrossRefGoogle Scholar
10. Moody, N. R. and Foiles, S. M., in Structure/Property Relationships for Metal/Metal Interfaces, edited by Romig, A. D., Fowler, D. E., and Bristowe, P. D., (Mater. Res. Symp. Proc, 229, Pittsburgh, PA 1991) pp. 179–185.Google Scholar
11. Lassila, D. H. and Birnbaum, H. K., Acta Metall. 34, 1237 (1986).Google Scholar
12. Windle, A. H. and Smith, G. C., J. Metal Science, 4, 136 (1970).Google Scholar
13. Daw, M. S. and Baskes, M. I., Phys. Rev. B 29, 6443 (1984).Google Scholar
14. Mills, M. J. and Daw, M. S., in High Resolution Electron Microscopy of Defects in Materials, edited by Sinclair, R., Smith, D. J., and Dahmen, U., (Mater. Res. Symp. Proc, 183, Pittsburgh, PA 1991) pp. 19–26.Google Scholar
15. Daw, M. S. and Foiles, S. M., Phys. Rev. B 21, 2128 (1987).Google Scholar
16. Foiles, S. M., in Surface Segregation Phenomena, edited by Dowbert, P. A. and Miller, A., (CRC Press, Boca Raton, 1990) p.79.Google Scholar
17. Foiles, S. M., Baskes, M. I., Melius, C. F., and Daw, M. S., J. of the Less Common Metals 130. 465 (1987).Google Scholar
18. Foiles, S. M., Baskes, M. I. and Daw, M. S., Phys. Rev. B 33, 7983 (1986).Google Scholar
19. Foiles, S. M., in High-Temperature Ordered Intermetallic Alloys II. edited by Stoloff, N. S., Koch, C. C., Liu, C. T., and Izumi, O., (Mater. Res. Symp. Proc, 81, Pittsburgh, PA 1987) pp. 51–56.Google Scholar
20. Beeler, J. R. Jr, in Radiation Effects Computer Simulations, Defects in Solids (series), 13. edited by Amelinckx, S., Gevers, R., and Nihoul, J., (North-Holland Publishing Co., New York, NY, 1983).Google Scholar
21. Baskes, M. I. and Vitek, V., Metall. Trans. A 16A, 1625 (1985).Google Scholar