Journal of Materials Research


Application of nucleation theory to the rate dependence of incipient plasticity during nanoindentation

Christopher A. Schuha1 and Alan C. Lunda1

a1 Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139


We propose a nucleation theory-based analysis for incipient plasticity during nanoindentation and predict the statistical distribution of rate-dependent pop-in events for many nominally identical indentations on the same surface. In the framework of stress-assisted, thermally activated defect nucleation, we quantitatively rationalize new nanoindentation measurements on 4H SiC and extract the activation volume of the nucleation events that mark the onset of plastic flow. We also illustrate how this statistical approach can differentiate between unique nucleation events for different indenter tip geometries.

(Received February 09 2004)

(Accepted April 12 2004)

Key Words:

  • Dislocations;
  • Nucleation;
  • Nanoindentation