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Indentation strain burst phenomenon induced by grain boundaries in niobium

Published online by Cambridge University Press:  03 March 2011

M.G. Wang
Affiliation:
Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road,Hong Kong, People’s Republic of China; and College of Science, Northeastern University, Shenyang 110006, People’s Republic of China
A.H.W. Ngan*
Affiliation:
Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road,Hong Kong, People’s Republic of China
*
a)Address all correspondence to this author.e-mail: [email protected]
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Abstract

Using depth-sensing indentation, a pop-in phenomenon induced by grain boundaries, namely, a sudden indenter displacement jump when indented near a grain boundary segment, was observed in polycrystalline niobium. This grain-boundary type of pop-in occurs at a larger force than the initial elasto-plastic pop-in, which is observed with and without a grain boundary nearby. The experimental results show that this pop-in effect has a close relationship with the misorientation across the grain boundary. The occurrence of this pop-in phenomenon is rationalized in terms of slip transmission across the grain boundary.

Type
Articles
Copyright
Copyright © Materials Research Society 2004

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References

REFERENCES

1.Aust, K.T., Hanneman, R.E., Niessen, P. and Westbrook, J.H.: Solute induced hardening near grain boundaries in zone refined metals. Acta Metall. 16, 291 (1968).Google Scholar
2.Watanabe, T., Kitamura, S. and Karashima, S.: Grain-boundary hardening and segregation in alpha-iron-tin alloy. Acta Metall. 28, 455 (1980).CrossRefGoogle Scholar
3.Harris, L.B., Howes, V.R. and Cutmore, N.G.: Microhardness of NaCl bicrystals. J. Am. Ceram. Soc. 65, 35 (1982).CrossRefGoogle Scholar
4.Chou, Y.T., Cai, B.C. Jr.Romig, A.D. and Lin, L.S.: Correlation between grain-boundary hardening and grain-boundary energy in niobium bicrystals. Philos. Mag. A 47, 363 (1983).CrossRefGoogle Scholar
5.Zhou, Z.Q. and Chou, Y.T.: Structure dependence of grain-boundary hardening in oriented niobium bicrystals. J. Less. Comm. Met. 114, 323 (1985).CrossRefGoogle Scholar
6.Wyrzykowski, J.W. and Grabski, M.W.: The Hall-Petch relation in aluminum and its dependence on the grain-boundary structure. Philos. Mag. A 53, 505 (1986).Google Scholar
7.Lee, C.S., Han, G.W., Smallman, R.E., Feng, D. and Lai, J.K.L.: The influence of boron-doping on the effectiveness of grain boundary hardening in Ni3Al. Acta Mater. 47, 1823 (1999).Google Scholar
8.Wo, P.C. and Ngan, A.H.W.: Investigation of slip transmission behavior across grain boundaries in polycrystalline Ni3Al using nanoindentation. J. Mater. Res. 19, 189 (2004).CrossRefGoogle Scholar
9.Baranova, G.K.: Etching of dislocations in niobium single-crystals. Scripta Metall. 11, 827 (1977).CrossRefGoogle Scholar
10.Page, T.F., Oliver, W.C. and McHargue, C.J.: The deformation-behavior of ceramic crystals subjected to very low load (nano)indentations. J. Mater. Res. 7, 450 (1992).Google Scholar
11.Gerberich, W.W., Nelson, J.C., Lilleodden, E.T., Anderson, P. and Wyrobek, J.T.: Indentation induced dislocation nucleation: The initial yield point. Acta Mater. 44, 3585 (1996).Google Scholar
12.Asif, S.A. Syed and Pethica, J.B.: Nanoindentation creep of single-crystal tungsten and gallium arsenide. Philos. Mag. A 76, 1105 (1997).Google Scholar
13.Bahr, D.F., Kramer, D.E. and Gerberich, W.W.: Non-linear deformation mechanisms during nanoindentation. Acta Mater. 46, 3605 (1998).Google Scholar
14.Michalske, T.A. and Houston, J.E.: Dislocation nucleation at nano-scale mechanical contacts. Acta Mater. 46, 391 (1998).Google Scholar
15.Gouldstone, A., Koh, H.J., Zeng, K.Y., Giannakopoulos, A.E. and Suresh, S.: Discrete and continuous deformation during nanoindentation of thin films. Acta Mater. 48, 2277 (2000).Google Scholar
16.Chiu, Y.L. and Ngan, A.H.W.: Time-dependent characteristics of incipient plasticity in nanoindentation of a Ni3Al single crystal. Acta Mater. 50, 1599 (2002).Google Scholar
17.Chiu, Y.L. and Ngan, A.H.W.: A TEM investigation on indentation plastic zones in Ni3Al(Cr,B) single crystals. Acta Mater. 50, 2677 (2002).CrossRefGoogle Scholar
18.Kramer, D., Huang, H., Kriese, M., Robach, J., Nelson, J., Wright, A., Bahr, D. and Gerberich, W.W.: Yield strength predictions from the plastic zone around nanocontacts. Acta Mater. 47, 333 (1999).Google Scholar
19.Ishio, K., Kikuchi, K., Kusano, M., Mizumoto, M., Mukugi, K., Naito, A., Ouchi, N. and Tsuchiya, Y. Fracture toughness and mechanical properties of pure niobium and welded joints for superconducting cavities at 4K. In Proceedings of the 9th Workshop on RF Superconductivity, edited by Rusnak, B. (Santa Fe, NM, 1999), Organized by Los Alamos National Laboratory, NM, Published online at http://lansce.lanl.gov/rfsc99/.Google Scholar
20.Johnson, K.L., Contact Mechanics (Cambridge University Press, Cambridge, U.K., 1985), pp. 173.CrossRefGoogle Scholar
21.Zeng, K., Söderlund, E., Giannakopoulos, A.E. and Rowcliffe, D.J.: Controlled indentation: A general approach to determine mechanical properties of brittle materials. Acta Mater. 44, 1127 (1996).CrossRefGoogle Scholar
22.Evans, P.R.V.: The dependence of the lower yield stress on grain size in niobium. J. Inst. Met. 92, 57 (1963).Google Scholar