Skip to main content Accessibility help
×
Home

Time-dependent incipient plasticity in Ni3Al as observed in nanoindentation

  • P.C. Wo (a1), L. Zuo (a1) and A.H.W. Ngan (a1)

Abstract

The time-dependent characteristics of incipient plasticity in Ni3Al during nanoindentation in the subcritical load regime were investigated statistically. The waiting time for incipient plasticity to occur at constant load was found to follow a Poisson-like distribution, with the peak shifting toward zero holding time as the load increased and eventually becoming an exponential distribution when the load was close to a critical value. The observed distribution of the strain burst waiting time at loads smaller than the critical value was inconsistent with the picture in which dislocations nucleated homogeneously out of the perfect crystal. The kinetics for the occurrence of strain burst in this case is thought to be governed by the accumulative growth of nucleation precursors.

Copyright

Corresponding author

a) Address all correspondence to this author. e-mail: hwngan@hku.hk

References

Hide All
1.Asif, S.A. Syed and Pethica, J.B.: Nanoindentation creep of single-crystal tungsten and gallium arsenide. Philos. Mag. A 76, 1105 (1997).
2.Gerberich, W.W., Nelson, J.C., Lilleodden, E.T., Anderson, R. and Wyrobek, J.T.: Indentation induced dislocation nucleation: The initial yield point. Acta Mater. 44, 3585 (1996).
3.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).
4.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).
5.Robertson, C.F. and Fivel, M.C.: A study of the submicron intent-induced plastic deformation. J. Mater. Res. 14, 2251 (1999).
6.Li, J., Ngan, A.H.W. and Gumbsch, P.: Atomic modelling of mechanical behaviour. Acta Mater. 51, 5711 (2003).
7.Gerberich, W.W., Venkataraman, S.K., Huang, H., Harvey, S.E. and Kohlstedt, D.L.: The injection of plasticity by millinewton contacts. Acta Mater. 43, 1569 (1995).
8.Wo, P.C. and Ngan, A.H.W.: Incipient plasticity during nanoscratch in Ni3Al. Philos. Mag. 84, 3145 (2004).
9.Schuh, C.A. and Lund, A.C.: Application of nucleation theory to the rate dependence of incipient plasticity during nanoindentation. J. Mater. Res. 19, 2152 (2004).
10.Li, H. and Ngan, A.H.W.: Size effects of nanoindentation creep. J. Mater. Res. 19, 513 (2004).
11.Liang, H.Y., Woo, C.H., Huang, H., Ngan, A.H.W. and Yu, T.X.: Dislocation nucleation in the initial stage during nanoindentation. Philos. Mag. 83, 3609 (2003).
12.Johnson, K.L.: Contact Mechanics(Cambridge Univ. Press, Cambridge, U.K., 1987), p. 93.
13.Voter, A.F. and Chen, S.P.: in Characterization of Defects in Materials, edited by Siegel, R.W., Weertman, J.R., and Sinclair, R. (Mater. Res. Soc. Symp. Proc. 82, Pittsburgh, PA, 1987), p. 175.
14.Vlassak, J.J. and Nix, W.D.: Measuring the elastic properties of anisotropic materials by means of indentation experiments. J. Mech. Phys. Solids 42, 1223 (1994).
15.Woodcock, L.V.: Isothermal molecular dynamics calculations for liquid salts chem. Phys. Lett. 10, 257 (1970).
16.Horstemeyer, M.F., Baskes, M.I. and Plimpton, S.T.: Length scale and time scale effects on the plastic flow of fcc metals. Acta Mater. 49, 4363 (2001).
17.Ngan, A.H.W., Wen, M. and Woo, C.H.: Atomistic simulation of Paidar-Pope-Vitek lock formation in Ni3Al. Comput. Mater. Sci. 29, 259 (2004).

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed